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Background: The initial graft tension applied during anterior cruciate ligament (ACL) graft fixation may promote posttraumatic osteoarthritis (PTOA). Purpose/Hypothesis: This study sought to assess the effect of initial graft tension and patient sex on PTOA outcomes at 10 to 12 years after ACL reconstruction (ACLR). The hypothesis was that there would be no group- or sex-based differences in outcomes. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: Patients were randomized to receive ACLR with a low or high initial graft tension. Outcomes were evaluated at 10 to 12 years postoperatively and compared with a matched, uninjured control group. Outcomes included clinical assessments (anteroposterior [AP] knee laxity measurement, International Knee Documentation Committee [IKDC] examination score), a functional assessment (single-leg hop for distance), patient-reported outcomes (Knee injury and Osteoarthritis Outcome Score [KOOS], 36-Item Short Form Health Survey, Tegner activity level, patient satisfaction), and PTOA imaging (Osteoarthritis Research Society International [OARSI] radiographic score and Whole-Organ Magnetic Resonance Imaging Score [WORMS]). Two-way mixed-model analyses of variance were used to evaluate differences in outcomes between tension groups and the control group and between female and male patients. Results: Both tension groups scored worse than the control group for the IKDC examination ( P≤ .021), KOOS (Pain, Activities of Daily Living, Sport/Recreation, and Quality of Life subscales) ( P≤ .049), and WORMS difference score ( P≤ .042). The low-tension group scored worse than the control group for KOOS Symptoms ( P = .016) and the OARSI difference score ( P = .015). The index limb had worse scores than the contralateral limb within the high-tension group for AP laxity ( P = .030) and hop deficit ( P = .011). This result was also observed within both tension groups for the WORMS ( P≤ .050) and within the low-tension group for the OARSI score ( P = .001). Male patients had higher Tegner scores (mean ± SE) relative to female patients (male, 5.49 ± 1.88; female, 4.45 ± 1.65) and worse OARSI difference scores (male, 1.89 ± 5.38; female, 0.244 ± 0.668) ( P = .007 and .034, respectively). However, no significant differences were detected between tension groups for any of the outcomes measured. Conclusion: Overall, ACLR failed to prevent PTOA regardless of initial graft tension. However, male patients treated with a low initial graft tension may be at greater risk for PTOA. These results do not support the hypothesis of no sex differences in outcomes at 10 to 12 years after ACLR.

Background: Anterior cruciate ligament (ACL) revision surgery is challenging for both patients and surgeons. Understanding the risk factors for failure after bridge-enhanced ACL restoration (BEAR) may help with patient selection for ACL restoration versus ACL reconstruction. Purpose: To identify the preoperative risk factors for ACL revision surgery within the first 2 years after BEAR. Study Design: Case-control study; Level of evidence, 3. Methods: Data from the prospective BEAR I, II, and III trials were used to determine the preoperative risk factors for ACL revision surgery. All patients with a complete ACL tear (aged 13-47 years, depending on the trial), who met all other inclusion/exclusion criteria and underwent a primary BEAR procedure within 30 to 50 days from the injury (dependent on the trial), were included. Demographic data (age, sex, body mass index), baseline patient-reported outcomes (International Knee Documentation Committee [IKDC] subjective score, Marx activity score), preoperative imaging results (ACL stump length, notch size, tibial slope), and intraoperative findings (knee hyperextension, meniscal status) were evaluated to determine their contribution to the risk of ipsilateral ACL revision surgery. Results: A total of 123 patients, with a median age of 17.6 years (interquartile range, 16-23 years), including 67 (54%) female patients, met study criteria. Overall, 18 (15%) patients required ACL revision surgery in the first 2 years after the BEAR procedure. On bivariate analyses, younger age ( P = .011), having a contact injury at the time of the initial tear ( P = .048), and increased medial tibial slope (MTS; P = .029) were associated with a higher risk of ipsilateral revision surgery. Multivariable logistic regression analyses identified 2 independent predictors of revision: patient age and MTS. The odds of ipsilateral revision surgery were decreased by 32% for each 1-year increase in age (odds ratio, 0.684 [95% CI, 0.517-0.905]; P = .008) and increased by 28% for each 1° increase in MTS (odds ratio, 1.280 [95% CI, 1.024-1.601]; P = .030). Sex, baseline IKDC or Marx score, knee hyperextension, and meniscal status were not significant predictors of revision. Conclusion: Younger age and higher MTS were predictors of ipsilateral ACL revision surgery after the BEAR procedure. Younger patients with higher tibial slopes should be aware of the increased risk for revision surgery when deciding to undergo ACL restoration.

ACL injuries place the knee at risk for post-traumatic osteoarthritis (PTOA) despite surgical anterior cruciate ligament (ACL) reconstruction. One parameter thought to affect PTOA risk is the initial graft tension. This randomized controlled trial (RCT) was designed to compare outcomes between two graft tensioning protocols that bracket the range commonly used. At 7 years postsurgery, we determined that most outcomes between the two tension groups were not significantly different, that they were inferior to an uninjured matched control group, and that PTOA was progressing in both groups relative to controls. The trial database was also leveraged to gain insight into mechanisms of PTOA following ACL injury. We determined that the inflammatory response at the time of injury undermines one of the joint's lubricating mechanisms. We learned that patients continue to protect their surgical knee 5 years postinjury compared to controls during a jump-pivot activity. We also established that presurgical knee function and mental health were correlated with symptomatic PTOA at 7 years, that there were specific anatomical factors associated with poor outcomes, and that there were no changes in outcomes due to tunnel widening in patients receiving hamstring tendon autografts. We also validated a magnetic resonance imaging technique to noninvasively assess graft strength. In conclusion, the RCT determined that initial graft tensioning does not have a major influence on 7-year outcomes. Therefore, surgeons can reconstruct the ACL using a graft tensioning protocol that is within the window of the two graft tensioning techniques evaluated in this RCT.

Anterior cruciate ligament (ACL) injuries are common in young and active patients. In this patient population, surgical treatment with an autograft tendon is recommended to reconstruct a new ACL. ACL reconstruction has a high patient satisfaction, improved patient reported outcomes and allows young patients to return to an active lifestyle, including sports. However, long-term follow-up shows these patients are at higher risk for degenerative arthritis, frequently at a young age. Recent research has focused on re-investigating the utility of performing an ACL repair rather than a reconstruction in the hopes that maintaining a patient's native ligament may not only restore knee stability, but provide improved knee kinematics and lessen the risk of late osteoarthritis and also limit donor site morbidity from autograft harvests. Historically, patients undergoing ACL repair suffered poor outcomes due to issues with intra-articular healing of the ligament; but now, with new bioengineering techniques, bridge-enhanced ACL repairs may provide a feasible alternative in the treatment of ACL injuries.

Background: Multiple anatomic features of the femoral condyles and tibial plateau have been shown to influence knee biomechanics and risk of anterior cruciate ligament (ACL) injury. However, it remains unclear how these anatomic factors affect the midterm outcomes of ACL reconstruction. Hypothesis: Decreased femoral notch width, increased posterior and coronal slopes, and decreased concavity of the tibial plateau are associated with inferior clinical, patient-reported, and osteoarthritis-related outcomes 7 years after ACL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: Prospectively collected data from 44 patients who did not have a subsequent graft or contralateral ACL failure within 7 years after unilateral ACL reconstruction were reviewed (mean ± SD age, 23.7 ± 9.2 years; 64% women). Notch width (after notchplasty), posterior slopes of the medial and lateral tibial plateau, maximum depth of the medial tibial plateau, and coronal tibial slope were measured from magnetic resonance images. Anatomic predictors of side-to-side differences in anterior-posterior knee laxity, Knee injury and Osteoarthritis Outcome Score (KOOS), medial joint space width, and side-to-side differences in Osteoarthritis Research Society International (OARSI) x-ray score, measured at 7 years, were identified with linear regression (bivariate) and stepwise regression (multivariate). Results: Increased posterior slope of the lateral tibial plateau was associated with increased side-to-side difference in knee laxity (bivariate model only), increased side-to-side difference in the OARSI score, and decreased KOOS subscores ( R2 > .10, P < .05). Increased posterior slope of the medial tibial plateau was associated with a higher side-to-side difference in the OARSI x-ray score (bivariate model only) and lower KOOS subscores ( R2 > .11, P < .03). Increased coronal tibial slope was associated with lower KOOS subscores ( R2 > .11, P < .03). Decreased medial tibial depth was associated with increased knee laxity as well as decreased KOOS subscores (ie, quality of life and symptoms; R2 > .12, P < .03). Postoperative notch width was not a significant predictor for any surgical outcome. None of the anatomic features were predictive of medial joint space width narrowing. Conclusion: Results partially support the hypothesis and highlight the importance of knee anatomy on several outcomes of ACL reconstruction among patients without subsequent graft or contralateral ACL injures. Increasing slopes in the coronal and sagittal planes with decreasing concavity of the medial tibial plateau lead to less favorable outcomes 7 years after surgery.

To investigate tibial tunnel widening in ACL reconstruction patients over seven years to establish the effects of initial graft tension on tibial widening and clinical outcomes when using both patellar tendon (BTB) and hamstring tendon (HS) grafts.Ninety patients, who were reconstructed with BTB or HS autografts, were randomized using one of two initial graft tension protocols; 1) tensioned to restore normal anteroposterior laxity ("low-tension"; n = 46) and 2) tensioned to over-constrain anteroposterior (AP) laxity by two millimeters ("high-tension"; n = 44). Seventy patients had post-surgical data with 45 available for review at seven years. Tunnel widening was assessed via radiographs at one-, three-, and seven-year follow-up. Patient-reported outcomes were compared.The mean ± 95% confidence intervals of the initial diameters for the BTB autografts were 10.3 ± 0.5 mm (Low-tension) and 10.2 ± 0.6 mm (High-tension) with final diameters of 10.8 ± 0.6 mm (Low-tension) and 9.9 ± 0.6 mm (High-tension). The initial diameters for HS autografts were 8.1 ± 0.9 mm (Low-tension) and 8.4 ± 0.7 mm (High-tension) with final diameters of 11.5 ± 1.1 mm (Low-tension) and 11.1 ± 0.9 mm (High-tension). For subjects with HS autografts, mean tunnel diameters significantly changed over time (p .001); no significant changes were observed in BTB autografts (p = .29). Change in diameter of the HS autograft group remained significantly greater than the BTB group at all time points for both tension groups (p .05). No differences in patient-reported outcomes were found between tension groups or graft types.Patients who underwent ACL-R with HS autograft exhibited tibial tunnel widening over seven years. Patients with BTB autografts did not experience widening, regardless of initial graft tension. Patient-reported outcomes were equivalent.

Background: BEAR (bridge-enhanced anterior cruciate ligament [ACL] restoration), a paradigm-shifting technology to heal midsubstance ACL tears, has been demonstrated to be effective in a single-center 2:1 randomized controlled trial (RCT) versus hamstring ACL reconstruction. Widespread dissemination of BEAR into clinical practice should also be informed by a multicenter RCT to demonstrate exportability and compare efficacy with bone--patellar tendon–bone (BPTB) ACL reconstruction, another clinically standard treatment. Purpose: To present the design and initial preparation of a multicenter RCT of BEAR versus BPTB ACL reconstruction (the BEAR: Multicenter Orthopaedic Outcomes Network [BEAR-MOON] trial). Design and analytic issues in planning the complex BEAR-MOON trial, involving the US National Institute of Arthritis and Musculoskeletal and Skin Diseases, the US Food and Drug Administration, the BEAR implant manufacturer, a data and safety monitoring board, and institutional review boards, can usefully inform both clinicians on the trial’s strengths and limitations and future investigators on planning of complex orthopaedic studies. Study Design: Clinical trial. Methods: We describe the distinctive clinical, methodological, and operational challenges of comparing the innovative BEAR procedure with the well-established BPTB operation, and we outline the clinical motivation, experimental setting, study design, surgical challenges, rehabilitation, outcome measures, and planned analysis of the BEAR-MOON trial. Results: BEAR-MOON is a 6-center, 12-surgeon, 200-patient randomized, partially blinded, noninferiority RCT comparing BEAR with BPTB ACL reconstruction for treating first-time midsubstance ACL tears. Noninferiority of BEAR relative to BPTB will be claimed if the total score on the International Knee Documentation Committee (IKDC) subjective knee evaluation form and the knee arthrometer 30-lb (13.61-kg) side-to-side laxity difference are both within respective margins of 16 points for the IKDC and 2.5 mm for knee laxity. Conclusion: Major issues include patient selection, need for intraoperative randomization and treatment-specific postoperative physical therapy regimens (because of fundamental differences in surgical technique, initial stability construct, and healing), and choice of noninferiority margins for short-term efficacy outcomes of a novel intervention with evident short-term advantages and theoretical, but unverified, long-term benefits on other dimensions.

This article investigates the clinical, functional, and radiographic outcomes in anterior cruciate ligament (ACL) reconstruction patients over 7 years to determine the effects of initial graft tension on outcomes when using patellar tendon (bone–tendon–bone [BTB]) and hamstring tendon (HS) autografts. Ninety patients, reconstructed with BTB or HS, were randomized using two initial graft tension protocols: (1) normal anteroposterior (AP) laxity (“low-tension”; n = 46) and (2) AP laxity overconstrained by 2 mm (“high-tension”; n = 44). Seventy-two patients had data available at 7 years, with 9 excluded for graft failure. Outcomes included the Knee Injury and Osteoarthritis Outcome Score, Short-Form-36 (SF-36), and Tegner activity scale. Clinical outcomes included KT-1000S and International Knee Documentation Committee examination score; and functional outcomes included 1-leg hop distance and peak knee extensor torque. Imaging outcomes included medial joint space width, Osteoarthritis Research Society International radiographic score, and Whole-Organ Magnetic Resonance Score. There were significantly improved outcomes in the high-tension compared with the low-tension HS group for SF-36 subset scores for bodily pain (p = 0.012), social functioning (p = 0.004), and mental health (p = 0.014) 84 months postsurgery. No significant differences in any outcome were found within the BTB groups. Tegner activity scores were also significantly higher for the high-tension HS group compared with the low-tension (6.0 vs. 3.8, p = 0.016). Patients with HS autografts placed in high tension had better outcomes relative to low tension for Tegner activity score and SF-36 subset scores for bodily pain, social functioning, and mental health. For this reason, we recommend that graft fixation be performed with the knee at 30-degree flexion (“high-tension” condition) when reconstructing the ACL with HS autograft.

Background:The “initial graft tension” applied at the time of graft fixation during anterior cruciate ligament (ACL) reconstruction surgery modulates joint contact mechanics, which in turn may promote posttraumatic osteoarthritis (OA).Purpose/Hypotheses:The study objectives were to compare clinical, functional, patient-reported, and OA imaging outcomes between 2 different initial laxity-based graft tension cohorts and a matched uninjured control group as well as to evaluate the effects of laxity-based graft tension on OA development at 84-month follow-up. The 2 laxity-based tension protocols were (1) to restore normal anteroposterior (AP) laxity at the time of surgery relative to the contralateral uninjured knee (low-tension group) or (2) to overconstrain AP laxity by 2 mm relative to the contralateral uninjured knee (high-tension group). The hypotheses were that (1) the high-tension group would have improved outcomes and decreased OA compared with the low-tension group after 84 months, and (2) the outcomes for the high-tension group would be equivalent to those for an age-, sex-, race-, and activity-matched group of control participants with uninjured knees.Study Design:Randomized controlled trial; Level of evidence, 1.Methods:Patients had their ACLs reconstructed with either a bone–patellar tendon–bone or 4-stranded hamstring autograft, and outcomes were compared with a matched control group. Outcomes were evaluated preoperatively and at 60 and 84 months postoperatively and included clinical (KT-1000 arthrometer AP laxity measurement and International Knee Documentation Committee [IKDC] examination score), functional (1-legged hop for distance and knee extensor torque), patient-reported (Knee injury and Osteoarthritis Outcome Score [KOOS], Short Form–36 [SF-36], and patient satisfaction survey), and OA imaging (measurement of joint space width [JSW], Osteoarthritis Research Society International [OARSI] radiographic score, and Whole-Organ Magnetic Resonance Imaging Score [WORMS]) components. Repeated-measures analyses of variance were used to evaluate differences in outcomes between the treatment groups and the control group.Results:There were significant differences between the 2 tension groups in 1 of 5 KOOS subscales (sports and recreation; P = .04) and 2 of 8 SF-36 subscales (vitality, mental health; P < .04) at 84 and 60 months, respectively. Both tension groups scored significantly worse than the control group in the IKDC examination ( P < .001), 1-legged hop ( P ≤ .017), KOOS quality of life and symptoms subscales ( P < .03), and OARSI radiographic score ( P ≤ .02) at 84 months. The low-tension group performed significantly worse than the control group on the KOOS pain subscale ( P = .03), SF-36 general health and social functioning ( P < .04), OARSI radiographic score ( P < .001), and WORMS ( P = .001), while the high-tension group had statistically different results than the control group in AP knee laxity ( P < .001), radiographic JSW ( P = .003), and OARSI radiographic score ( P = .02) as well as significantly more subsequent knee injuries ( P = .02) at 84 months.Conclusion:The results do not support the hypotheses that the high-tension group would have improved outcomes when compared with the low-tension group after 84 months of healing or that the outcomes for the high-tension group would be equivalent to those for the matched control group. While there were minor differences in patient-reported outcomes between the 2 laxity-based tension groups, all other outcomes were similar.Registration:NCT00434837

Background: Anterior cruciate ligament (ACL) tears are associated with the development of knee osteoarthritis despite ACL reconstruction surgery. However, little evidence is available to determine which patients will develop symptomatic knee osteoarthritis. Purpose: To determine if preoperative outcome measures—KOOS (Knee injury and Osteoarthritis Outcome Score) and SF-36 (36-item Short Form Health Survey)—were associated with the development of a symptomatic knee 7 years after ACL reconstruction. A secondary goal was to examine the relationship between imaging evidence of knee osteoarthritis and development of knee pain. Study Design: Case-control study; Level of evidence, 3. Methods: Prospectively collected data from 72 patients were reviewed with 7-year follow-up after unilateral ACL reconstruction. Patients were divided into symptomatic and asymptomatic groups based on the previously defined KOOS pain ≤72. Demographic variables and preoperative KOOS and SF-36 scores were compared between groups. Radiographic and magnetic resonance imaging data were used to evaluate differences in joint space width, Osteoarthritis Research Society International radiographic score, and the Whole-Organ Magnetic Resonance Imaging Score between groups. Univariate and multivariate analyses were performed to identify potential predictors of pain at 7-year follow-up. Wilcoxon sum rank and t tests were used to compare imaging findings between the symptomatic and asymptomatic patients at 7 years. Results: According to KOOS pain, 7 of the 72 patients available at 7-year follow-up formed the symptomatic group. No differences were found between groups in regard to demographic variables or intraoperative findings. In multivariate analysis, lower preoperative scores for KOOS sports/recreation ( P = .005) and SF-36 mental health ( P = .025) were associated with a painful knee at 7 years, with increased odds of 82% and 68% per 10-unit decrease, respectively. The Whole-Organ Magnetic Resonance Imaging Score at 7 years showed evidence of osteoarthritic changes in the symptomatic group as compared with the asymptomatic group ( P = .047). However, there were no significant differences in the Osteoarthritis Research Society International radiographic score ( P = .051) or joint space width ( P = .488) between groups. Conclusion: Lower preoperative KOOS and SF-36 scores were associated with those patients who developed symptomatic knee osteoarthritis 7 years after ACL reconstruction.

Objectives: ACL reconstruction is effective in restoring knee stability and returning a majority of patients to sports. However, these patients remain at a higher risk of developing knee OA and a subset of patients have persistent pain. It is currently unknown what pre-operative and early post-operative measures can be used to help predict outcomes following ACL reconstruction at 7 years. The purpose of this study was to compare clinical data, patient-reported outcomes and imaging findings of knee arthrosis between symptomatic and asymptomatic subject at 84 month follow up after primary ACL reconstruction. Methods: We reviewed prospectively collected data from our previously published randomized controlled trial of outcomes of ACL reconstruction. Clinical, radiographic, and patient-reported outcomes were collected pre-operatively, and at 1,3,5, and 7 years post-operatively. Patient-reported outcome measures included SF-36 and KOOS. Imaging studies were used to evaluate medial joint space width, Osteoarthritis Research Society International (OARSI) radiographic score, and Whole-Organ Magnetic Resonance Imaging Score (WORMS). Symptomatic subjects were defined as those with KOOS-pain subscores, measured at 84 months post-operatively, two standard deviations below the mean for healthy athletic patients with a history of a knee ligament injury. These subjects were compared to the remainder of the study group to identify factors predictive of poor outcomes. Results: patient-report outcome measures were available for 72 patients at 84 month follow up. Of these, 7 subjects had KOOS pain scores less than 72.5 and were considered the symptomatic subgroup. Low pre-operative KOOS-ADL and KOOS-sports subscores were associated with low KOOS pain scores at 7 year follow up. SF-36 scores were lower at most time periods in the symptomatic group. In addition, OARSI scores were worse at 1,5, and 7 years, and WORMS showed greater signs of cartilage injury at 3 and 5 years post operatively in the symptomatic group. Medial joint space width was found to be significantly decreased in symptomatic patients at 7 year follow up. Conclusion: Low preoperative KOOS-ADL and KOOS-sports subscores were found to be associated with worse pain outcomes in primary ACL reconstruction patients at 84 months post-operatively. Additionally, multiple post-operative measures were found to be indicative of the ACL reconstruction patients that would have a symptomatic knee. WORMS collected at 3 and 5 years was shown to identify those subjects that would be symptomatic at 7 years. Also, radiographic changes were evident in this group with significantly decreased medial joint space width relative to control subjects.

Background: Orthopaedic surgery residents may cover athletic events, although the training provided to prepare residents for this role and oversight from attending physicians during these activities is not well understood. Purpose: To survey orthopaedic residents about the training provided by their residency program for on-field athletic coverage and to understand their levels of preparation for this role and confidence in treating commonly encountered on-field conditions. Study Design: Descriptive epidemiology study. Methods: An anonymous survey was emailed to residents in all American College of Graduate Medical Education–accredited, allopathic, nonmilitary orthopaedic surgery residency programs. This survey queried residents about their demographics, the opportunities their residencies require or allow for athletic coverage, their level of preparation for serving an on-field physician, and their comfort level with treating a number of on-field conditions. Likert-type scales were used to assess resident comfort level for treating 13 orthopaedic and nonorthopaedic conditions as well as their perceived level of preparedness. Results: Of 148 residency programs contacted, 57 programs responded (39%). Of the 57 programs responding, 51 (89.5%) allowed or required residents to cover athletic events, and 27 of 51 (52.9%) reported that training to prepare for this role was provided. Only 6 of 24 programs without training available (25%) had direct attending supervision of residents at all athletic events. Residents who answered that their residency programs mandate training prior to their participation in athletic coverage activities reported a higher level of preparation for this role than those with no training, optional training, or those who were unsure of their training requirement ( P < .0001, P = .035, and P = .013, respectively). In addition, the more senior the resident was, the higher the level of confidence was in treating all orthopaedic and some nonorthopaedic conditions. Residents who had mandatory training displayed a higher comfort level in treating on-field orthopaedic and nonorthopaedic conditions than those without training. Conclusion: Formal training of orthopaedic residents prior to their covering athletic events can improve confidence in treating orthopaedic and nonorthopaedic conditions. Many programs do not ensure that residents are familiar with key and potentially life-saving equipment. An opportunity exists to improve resident education.

Background: Clinical, functional, and patient-oriented outcomes are commonly used to evaluate the efficacy of treatments after anterior cruciate ligament (ACL) injury; however, these evaluation techniques do not directly measure the biomechanical changes that occur with healing. Purpose: To determine if the magnetic resonance (MR) image–derived parameters of graft volume and signal intensity (SI), which have been used to predict the biomechanical (ie, structural) properties of the graft in animal models, correlate with commonly used clinical (anteroposterior [AP] knee laxity), functional (1-legged hop), and patient-oriented outcome measures (Knee Injury and Osteoarthritis Outcome Score [KOOS]) in patients 3 and 5 years after ACL reconstruction. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: Based on a subset of participants enrolled in an ongoing ACL reconstruction clinical trial, AP knee laxity, 1-legged hop test, and KOOS were assessed at 3- and 5-year follow-up. Three-dimensional, T1-weighted MR images were collected at each visit. Both the volume and median SI of the healing graft were determined and used as predictors in a multiple regression linear model to predict the traditional outcome measures. Results: Graft volume combined with median SI in a multiple linear regression model predicted 1-legged hop test at both the 3- and 5-year follow-up visits ( R2 = 0.40, P = .008 and R2 = 0.62, P = .003, respectively). Similar results were found at the 5-year follow-up for the KOOS quality of life ( R2 = 0.49, P = .012), sport/function ( R2 = 0.37, P = .048), pain ( R2 = 0.46, P = .017), and symptoms ( R2 = 0.45, P = .021) subscores, although these variables were not significant at 3 years. The multiple linear regression model for AP knee laxity at 5-year follow-up approached significance ( R2 = 0.36, P = .088). Conclusion: The MR parameters (volume and median SI) used to predict ex vivo biomechanical properties of the graft in an animal model have the ability to predict clinical or in vivo outcome measures in patients at 3- and 5-year follow-up. Clinical Relevance: Results from this study may enhance clinical evaluation of graft health by relating the MR parameters of volume and median SI to traditional outcome measures and could potentially aid researchers in determining the appropriate timing for athletes to return to sport.

The purpose of this study was to compare kinetic and knee kinematic measurements from male and female anterior cruciate ligament (ACL)-intact (ACLINT) and ACL-reconstructed (ACLREC) subjects during a jump-cut maneuver using biplanar videoradiography.Twenty subjects were recruited; 10 ACLINT (5 men and 5 women) and 10 ACLREC (4 men and 6 women, 5 yr postsurgery). Each subject performed a jump-cut maneuver by landing on a single leg and performing a 45° side-step cut. Ground reaction force (GRF) was measured by a force plate and expressed relative to body weight. Six-degree-of-freedom knee kinematics were determined from a biplanar videoradiography system and an optical motion capture system.ACLINT female subjects landed with a larger peak vertical GRF (P0.001) compared with ACLINT male subjects. ACLINT subjects landed with a larger peak vertical GRF (P ≤ 0.036) compared with ACLREC subjects. Regardless of ACL reconstruction status, female subjects underwent less knee flexion angle excursion (P = 0.002) and had an increased average rate of anterior tibial translation (0.05%·ms ± 0.01%·ms, P = 0.037) after contact compared with male subjects. Furthermore, ACLREC subjects had a lower rate of anterior tibial translation compared with ACLINT subjects (0.05%·ms ± 0.01%·ms, P = 0.035). Finally, no striking differences were observed in other knee motion parameters.Women permit a smaller amount of knee flexion angle excursion during a jump-cut maneuver, resulting in a larger peak vertical GRF and increased rate of anterior tibial translation. Notably, ACLREC subjects also perform the jump cut maneuver with lower GRF than ACLINT subjects 5 yr postsurgery. This study proposes a causal sequence whereby increased landing stiffness (larger peak vertical GRF combined with less knee flexion angle excursion) leads to an increased rate of anterior tibial translation while performing a jump-cut maneuver.

Background:The initial graft tension applied at the time of anterior cruciate ligament (ACL) reconstruction alters joint contact and may influence cartilage health. The objective was to compare outcomes between 2 commonly used “laxity-based” initial graft tension protocols.Hypotheses:(1) The high-tension group would have less knee laxity, improved clinical and patient-oriented outcomes, and less cartilage damage than would the low-tension group after 36 months of healing. (2) The outcomes of the high-tension group would be equivalent to those of a matched control group.Study Design:Randomized controlled trial; Level of evidence, 1.Methods:Ninety patients with isolated unilateral ACL injuries were randomized to undergo ACL reconstruction using 1 of 2 initial graft tension protocols: (1) autografts tensioned to restore normal anterior-posterior (AP) laxity at the time of surgery (ie, low tension; n = 46) and (2) autografts tensioned to overconstrain AP laxity by 2 mm (ie, high tension; n = 44). Sixty matched healthy patients formed the control group. Outcomes were assessed preoperatively, intraoperatively, and at 6, 12, and 36 months after surgery.Results:No significant differences were found between the 2 initial graft tension protocols for any of the outcome measures at 36 months. However, there were differences when comparing the 2 treatment groups to the control group. On average, AP laxity was 2 mm greater in the ACL-reconstructed groups than in the control group ( P < .007). International Knee Documentation Committee (IKDC) knee evaluation scores, peak isokinetic knee extension torques, and 4 of 5 Knee Osteoarthritis Outcome Scores (KOOS) were significantly worse than the control group ( P < .001, P < .027, and P < .05, respectively). Short Form–36 Health Survey (SF-36) scores and reinjury rates were similar between groups at 36 months. Although there were significant changes in radiography and magnetic resonance imaging present in the ACL-reconstructed knees of both treatment groups, the magnitude was relatively small and likely clinically insignificant at 36 months.Conclusion:Both laxity-based initial graft tension protocols produced similar outcomes without fully restoring joint function or patient-oriented outcomes (KOOS) when compared with the control group. There was minimal evidence of cartilage damage 36 months after surgery.

SummaryObjectiveEarly detection of glycosaminoglycan (GAG) loss may provide insight into mechanisms of cartilage damage in the anterior cruciate ligament (ACL)-injured patient. We hypothesized that tibial and femoral Delayed Gadolinium-Enhanced MR Imaging of Cartilage (dGEMRIC) indices would be lower in the medial compartment of the ACL-injured knee than in the contralateral, uninjured knee, and that scan order (i.e., whether the injured or the uninjured knee was imaged first) would not affect the indices.Methods15 subjects with unilateral ACL injuries received a double dose of gadolinium [Gd(DTPA)2−] intravenously. After 90min, both knees were sequentially imaged. The injured knee was scanned first in the odd-numbered subjects and second in the even-numbered subjects. The dGEMRIC indices of the median slice of the medial compartment were determined using the MRIMapper software. Index comparisons were made between knee status (ACL-injured vs uninjured), scan order (ACL-injured first vs uninjured first), and cartilage location (tibia vs femur) using a mixed model.ResultsThere was a significant difference in the mean dGEMRIC indices of the medial compartment between injured and uninjured knees (P

Purpose: Our purpose was to document the tibiofemoral (TF) compression forces produced during clinical initial graft tension protocols. Methods: An image analysis system was used to track the position of the tibia relative to the femur in 11 cadaveric knees. TF compression forces were quantified by use of thin-film pressure sensors. Before anterior cruciate ligament (ACL) reconstructions were performed with patellar tendon grafts, measurements of TF compression force were obtained from the ACL-intact knee with knee flexion. ACL reconstructions were then performed by use of "force-based" and "laxity-based" graft tension approaches. Within each approach, high- and low-tension conditions were compared with the ACL-intact condition over the range of knee flexion angles. Results: The TF compression forces for all initial graft tension conditions were significantly greater than those of the normal knee when the knee was in full extension (0°). The TF compression forces produced with the laxity-based approach were greater than those produced with the force-based approach. However, the laxity-based approach was necessary to restore normal laxity at the time of surgery. Conclusions: The results of this study show that initial graft tension conditions influence TF compressive forces at the time of surgery and that clinically relevant initial graft tension conditions produce different TF compressive forces. Clinical Relevance: This study showed that the TF compression forces were greater in the ACL-reconstructed knee for all of the initial graft tension conditions when compared with the ACL-intact knee and that clinically relevant initial graft tension conditions produce different TF compressive forces.

This study evaluated the effectiveness of small intestine submucosa used as a graft to fill surgically created meniscal defects in a large animal model. Four goats underwent unilateral interior subtotal meniscectomies (approximately 70%) within the avascular portion of the medial meniscus. The contralateral meniscus acted as a control. Grafts of porcine small intestine submucosa were trimmed to fill the resected defects and sutured into place. After surgery the operated knees were casted in partial flexion to limit weight bearing on the affected limb. All of the animals were sacrificed at 12 weeks at which point meniscal regeneration and articular cartilage degradation were evaluated by gross and histologic examination. Grossly, the defects in the small intestine submucosa-grafted goats were partially filled with meniscal-appearing connective tissue. Histologically, the replacement tissue was typified by the presence of dense, cellular, irregularly organized connective tissue. Evaluation of the articular cartilage displayed increased degeneration in the grafted compartment of the operative knees. Each of the operative menisci partially regenerated. The grafts were conducive to repopulation with host meniscal elements. Despite partial meniscal regeneration, comparatively more articular cartilage degeneration in the treated knees was observed than in the untreated contralateral controls.

OBJECTIVE. The purpose of this article is to highlight the normal anatomic features of the meniscal roots on photographs of dissected cadaveric knee specimens and 3-T MR images.CONCLUSION. The meniscal roots, which are critical attachment sites of the medial and lateral menisci to the central tibial plateau, are well-visualized on intermediate-weighted, turbo spin-echo 3-T MRI and can be identified in proximity to the tibial insertions of the anterior and posterior cruciate ligaments.

To retrospectively determine the prevalence of posterior lateral meniscus root tears (LMRTs), as depicted on magnetic resonance (MR) images, in patients with an anterior cruciate ligament (ACL) tear and to investigate the association of LMRTs with lateral meniscus extrusion and other ligament injuries.Institutional review board approval was obtained; informed consent was not required. This study was HIPAA compliant. MR images were obtained in 174 male and 119 female patients (mean age, 37 years; age range, 16-87 years) and retrospectively reviewed for LMRT, medial meniscus root tear (MMRT), nonroot meniscus tear, meniscus extrusion, and presence of meniscofemoral ligaments (MFLs). The chi2 and unpaired Student t tests were performed.In 33 patients, 34 meniscus root tears were identified. An LMRT was present in 26 (9.8%) of 264 patients, and an MMRT was present in eight (3.0%) (P=.008). Lateral meniscus extrusion was present in six (23%) of 26 LMRTs and five (2.2%) of 231 patients with normal meniscus roots (P.001). Complex or deep radial tears were found in three of five cases of lateral meniscus extrusion and normal root. The MFL was not observed in five (19%) of 26 studies of an LMRT. Among these 26 studies of an LMRT, lateral meniscus extrusion was identified in three (14%) of 21 cases in which the MFL was intact and in three (60%) of five cases in which the MFL was not identified (P.03). Prevalence of an extruded meniscus was seven (88%) of eight for an MMRT and six (23%) of 26 for an LMRT (P=.001).Prevalence of LMRTs is greater than that of MMRTs in patients with an ACL tear. LMRTs and complex and radial tears are associated with lateral meniscus extrusion; an absent MFL is more prevalent in patients with LMRTs and when the meniscus is extruded.

Ulnar collateral ligament (UCL) insufficiency is potentially a career threatening, or even a career ending, injury, particularly in overhead throwing athletes. The evolution of treating modalities provides afflicted athletes with the opportunity to avoid premature retirement. There have been several clinical and basic science research efforts which have investigated the pathophysiology of UCL disruption, the biomechanics specific to overhead throwing, and the various types of treatment modalities. UCL reconstruction is currently the most commonly performed surgical treatment option. An in depth analysis of the present treatment options, both non-operative and operative, as well as their respective results and biomechanical evaluation, is lacking in the literature to date. This article provides a comprehensive current review and comparative analysis of these modalities. Over the last 30 years there has been an evolution of the original UCL reconstruction. Yet, despite the variability in modifications, such as the docking technique, interference screw fixation, and use of suture anchors, the unifying concepts of UCL reconstruction are that decreased dissection of the flexor-pronator mass and decreased handling of the ulnar nerve leads to improved outcomes.

PURPOSE OF REVIEW: The recent literature on the factors that initiate and accelerate the progression of osteoarthritis following ligament injuries and their treatment is reviewed. RECENT FINDINGS: The ligament-injured joint is at high risk for osteoarthritis. Current conservative (e.g. rehabilitation) and surgical (e.g. reconstruction) treatment options appear not to reduce osteoarthritis following ligament injury. The extent of osteoarthritis does not appear dependent on which joint is affected, or the presence of damage to other tissues within the joint. Mechanical instability is the likely initiator of osteoarthritis in the ligament-injured patient. SUMMARY: The mechanism osteoarthritis begins with the injury rendering the joint unstable. The instability increases the sliding between the joint surfaces and reduces the efficiency of the muscles, factors that alter joint contact mechanics. The load distribution in the cartilage and underlying bone is disrupted, causing wear and increasing shear, which eventually leads to the osteochondral degeneration. The catalyst to the mechanical process is the inflammation response induced by the injury and sustained during healing. In contrast, the inflammation could be responsible for onset, while the mechanical factors accelerate progression. The mechanisms leading to osteoarthritis following ligament injury have not been fully established. A better understanding of these mechanisms should lead to alternative surgical, drug, and tissue-engineering treatment options, which could eliminate osteoarthritis in these patients. Progress is being made on all fronts. Considering that osteoarthritis is likely to occur despite current treatment options, the best solution may be prevention.

Despite a number of persistent complications, allograft reconstruction after tumor resection oftentimes is the best solution after resection of the distal femur or proximal tibia. In this work, the results of allograft reconstruction will be reviewed, a theoretical basis for our current operative techniques formulated, and the details of our operative techniques will be thoroughly described. Complications can be minimized by attention to technical details of the surgical reconstruction, which include creation of an allograft/cement composite, "rigid" internal fixation, contemporary ligament reconstruction utilizing bone plugs, and reconstitution of the soft tissue envelope. Most complications that do occur can be successfully treated, with the exception being allograft infection. If degenerative arthritis develops, a conventional resurfacing arthroplasty can be performed into the allograft.

Background An intriguing explanation for the disproportionately high rate of anterior cruciate ligament injury in female athletes is that the structural properties of the anterior cruciate ligament are affected by the menstrual hormones. Whether this actually occurs, however, is the subject of ongoing debate. Hypotheses (1) Anterior cruciate ligament laxity is different in the follicular, ovulatory, and luteal phases of the menstrual cycle, and (2) exercise exacerbates the difference in anterior cruciate ligament laxity in the 3 phases. Methods Over the course of 10 weeks, repeated knee laxity measurements were taken on 27 high-level female athletes, before and after exercise. Point in the menstrual cycle was determined with charts of waking temperature and menstruation. The independent effects of menstrual phase and exercise were evaluated using generalized estimating equations. Results Data from 18 participants were included in the final analysis. There were no significant differences in anterior cruciate ligament laxity in any of the 3 menstrual phases, before or after exercise. Conclusions Anterior cruciate ligament laxity is not significantly different during the follicular, ovulatory, and luteal phases of the menstrual cycle, and bicycling exercise does not exacerbate or create any differences in anterior cruciate ligament laxity.

Purpose: The present investigation is a preliminary study designed to evaluate the use of a collagen-based biomaterial, chemically unaltered porcine small intestine submucosa (SIS), as a scaffold for meniscal tissue regeneration. Type of Study: Basic research. Methods: Surgical defects were created in the lateral menisci of 12 mature New Zealand white rabbits. The defects were repaired with a similarly shaped and sized wedge of a new collagenous biomaterial (SIS) and sutured in place. The opposite knees served as controls by creating a defect in the lateral meniscus without filling with SIS graft. Full cage activity was allowed until the animals were killed at 4, 12, and 24 weeks. Results: At 4 weeks, the graft material retained its physical position and grossly appeared soft and translucent. Histologically, cellular elements had infiltrated between the laminates of the graft. At 12 weeks, the graft grossly appeared more solid and opaque. Histologically, the host meniscal fibrochondrocytes were seen streaming into the peripheral margin of the graft. Early repopulation of the graft with apparently differentiated meniscal tissue was observed. At 24 weeks, the meniscus defect was grossly healed across and looked virtually normal: the normal meniscal shape, contour, consistency, and color had been replicated. Histologically, the healing tissue showed infiltration of what appeared to be meniscal fibrochondrocytes and connective tissue resembling the host meniscal tissue. The graft was nearly totally replaced by host tissue. Conclusions: This pilot animal study demonstrates that the multilaminated collagenous graft is conducive for cellular repopulation with host meniscal elements, and, by 24 weeks, is capable of supporting complete healing of a large meniscal defect. Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 2 (February), 2001: pp 151–159

Study objective: To determine the influence of football helmet and shoulder pads, alone or in combination, on alignment of the unstable cervical spine. Methods: The alignment of the intact cervical spine in 8 cadavers was assessed radiographically under 4 different football equipment conditions: (1) no equipment, (2) helmet only, (3) helmet and shoulder pads, and (4) shoulder pads only. Each specimen was then surgically destabilized at C5-C6 to simulate a flexion-distraction injury. Repeat radiographs were obtained under the same 4 equipment conditions, and alignment of the unstable segment was analyzed. Results: Before the destabilization, neutral alignment was maintained when both helmet and shoulder pads were in place. The "helmet only" condition caused a significant decrease in lordosis (mean, 9.6±4.7 degrees), whereas the "shoulder pads only" condition caused increased lordosis (13.6±6.3 degrees). After destabilization, the "helmet-only" condition demonstrated significant mean increases in C5-C6 forward angulation (16.5±8.6 degrees), posterior disc space height (3.8±2.3 mm), and dorsal element distraction (8.3±5.4 mm). Conclusion: Our flexion-distraction model demonstrated that immobilization of the neck-injured football player with only the helmet in place violates the principle of splinting the cervical spine in neutral alignment. By extrapolation to an extension-type injury, immobilization with only the shoulder pads left in place similarly violates this principle. In order to maintain a neutral position and minimize secondary injury to the cervical neural elements, the helmet and shoulder pads should be either both left on or both removed in the emergency setting. [Gastel JA, Palumbo MA, Hulstyn MJ, Fadale PD, Lucas P: Emergency removal of football equipment: A cadaveric cervical spine injury model. Ann Emerg Med October 1998;32:411-417.]

Musculoskeletal injuries constantly provide challenges to the team physician, including those to the shoulder. Shoulder injuries are common in athletes, whether as a result of direct contact from a collision or from repetitive overhead motion. This article reviews sports-related injuries to the shoulder, including similarities between sports, clinical evaluation, and rehabilitation of the athletes.

Anterior cruciate ligament (ACL) rupture is a common knee injury and an understanding of current medical knowledge regarding its management is essential. Accurate and prompt diagnosis requires an awareness of injury mechanisms and risk factors, common symptoms and physical/radiologic findings. Early mobilization and physical therapy improves outcomes regardless of treatment modality. Many older patients regain sufficient stability and function after non-operative rehabilitation. Early ACL reconstruction is appropriate for younger patients and those who engage in activities requiring frequent pivoting and rapid direction changes. ACL surgery involves reconstruction of the torn ligament tissue with various replacement graft options, each with advantages and disadvantages. The guidance of a knowledgeable and experienced therapist is required throughout an intensive and prolonged rehabilitation course. Generally excellent outcomes and low complication rates are expected, but treatment does not prevent late osteoarthritis.

No universally accepted management protocol is avail able for dealing with the protective equipment worn by a neck-injured football player. The purpose of this ca daveric study was to determine the effects of the hel met and shoulder pads on the alignment of 1) the intact lower cervical spine and 2) the partially destabilized C5-6 motion segment. In Group I cadavers ( N = 15), the lower cervical spine was tested in an intact condi tion. In Group II ( N = 8), the C5-6 motion segment was tested in both an intact and a partially destabilized condition. Each cadaver was placed supine on a back- board and four lateral cervical radiographs were ob tained as follows: no protective equipment, helmet only, helmet and shoulder pads, and shoulder pads only. Results for Group I showed that wearing both helmet and shoulder pads did not result in a significant change in cervical lordosis when compared with the neutral position (i.e., the no-equipment test). Cervical lordosis was significantly decreased in the helmet-only category (mean, 9.6°) and significantly increased in the shoulder pads-only category (mean, 13.6°). In Group II, destabilized specimens under the helmet test situa tion showed a significant mean increase in C5-6 for ward angulation (16.5°), posterior disk space height (3.8 mm), and dorsal element distraction (8.3 mm). Immobilizing the neck-injured football player with only the helmet or only the shoulder pads in place violates the principle of splinting the cervical spine in neutral alignment, according to our findings. We support the concept that removal of the helmet and shoulder pads should be an all-or-none proposition.

Deep vein thrombosis (DVT) with subsequent pulmonary emboli (PE) is the most life-threatening complication of knee arthroscopy. Although the incidence of clinically diagnosed DVT after arthroscopy is low, clinical examination is less sensitive and specific than other diagnositc modalities for the detection of venous clot. This study used compression ultrasound to prospectively evaluate patients before and after arthroscopic surgery for the presence of DVT. Preoperatively, patients were screened for DVT risk factors. Eighty-five patients completed the study. Three asymptomatic "silent" DVTs were identified, for an incidence of 3.5%. There was no statistically significant difference between those with and without risk factors for the development of DVT.

The importance of a thorough knowledge of regional anatomy in any surgical discipline cannot be overemphasized. This is particularly true for the orthopedist as arthroscopic procedures continue to evolve with our increased understanding of shoulder pathology and as we attempt to improve patient outcomes. Surface and bony anatomy allow the arthroscopist to infer the location of the glenohumeral joint and subacromial space. Proper portal placement allows access to these regions without risk of neurovascular, tendon, or articular injury. Glenohumeral and subacromial anatomy can be clearly seen arthroscopically with many normal variants. Knowledge of normal shoulder anatomy allows the orthopedic surgeon to safely and successfully treat pathologic conditions.

Background The Internet is a popular and powerful resource used by both clinicians and patients. However, medical information on the Internet is often unregulated, biased, and of poor quality. Given the frequency of ACL injuries in young women, this topic was used as a case study to examine the information available to patients on the Internet. Methods An Internet search was performed using the top three general search engines for four different search phrases related to ACL injuries in females. The top ten sites from each search were analyzed on the basis of both website interface and a specific content scoring guide. Results A total of 35 unique websites were analyzed. The majority of websites were authored by a layperson or had an unidentified author. Readability data indicated that many sites were written at literacy levels that were too difficult for the average reader. Finally, the average content analysis score for all sites was 41.6 out of a possible 100 points (range 10–87.5); only one-third of the websites cited references for the information provided. Conclusions We found the Internet information on ACL injuries in women to be largely unsupported, outdated and too difficult for the average reader to comprehend. The average site covered less than half of the topics that we considered relevant to ACL injuries in females indicating that information available on the Internet is largely incomplete. Clinical relevance Clinicians should be aware of the deficiencies in Internet information in order to appropriately address these issues with patients.

Patellar dislocations in adolescents may cause osteochondral fractures of the patella. The aim of this study was to review the outcomes of adolescent patients who underwent surgical intervention for patellar osteochondral fracture following patellar dislocation. Nine patients who underwent surgery for osteochondral fracture of the patella following dislocation were identified retrospectively. Following arthroscopic examination, if the fragment was large enough to support fixation, headless screws or bioabsorbable pins were used. Otherwise, the loose body was excised, and the donor site was managed with a microfracture. Postoperatively, patients were assessed using the International Knee Documentation Committee (IKDC) and Knee injury and Osteoarthritis Outcome Score (KOOS) outcome measures. The average age of the patients was 14.6 with average follow-up 30.2 months. Four of the nine patients underwent fixation, while five patients underwent removal of loose body with microfracture. The average defect size in the nonfixation group was 1.2 cm2 compared with 3.2 cm2 in the fixation group. The IKDC scores for fixation and nonfixation groups were 63.9 (SD = 18) and 76.1 (SD = 11.7), respectively. The KOOS subscale scores for symptoms, function in sports and recreation, and knee-related quality of life were higher for the nonfixation group when compared to the fixation group. This is the first known series examining surgical outcomes of osteochondral fractures of the patella following patellar dislocations in the adolescent population. While patients without fixation were less symptomatic in this series, this may be attributable to more severe injuries in patients undergoing fracture fixation. Retrospective case series, Level IV.

Purpose To perform a biomechanical analysis of suture bridge fixation for tibial eminence fractures using PushLock anchors (Arthrex, Naples, FL) and compare it with traditional suture fixation and screw fixation. Methods This study used 24 porcine knees, divided into 3 comparison fixation groups: PushLock suture bridge fixation, screw fixation, and suture fixation. Each knee was dissected of all soft tissue, leaving only the anterior cruciate ligament. A tibial eminence fracture was created with disruption of the posterior hinge, and each knee was fixed with a randomly assigned fixation technique. After fixation, each knee underwent 2 phases of biomechanical testing. The initial cyclic dynamic phase assessed the displacement change after 200 cycles (in millimeters) and initial stiffness (in Newtons per millimeter) of the fixation construct. After completion of dynamic testing, each specimen underwent a single tensile failure test load to assess ultimate failure load (in Newtons) and displacement (in millimeters) to ultimate failure. Results There was a significant difference for the load-to-failure outcome variable among treatment groups ( P = .004 by analysis of variance, 1 – β = 0.851). Mean ultimate failure load borne by the PushLock fixation group was statistically significantly higher in comparison with the screw ( P = .007) and suture ( P = .017) fixation groups. For the cyclical testing, the primary outcome variable of displacement change after 200 loading cycles failed to show a significant difference among the 3 groups ( P = .412). Conclusions Suture bridge fixation with PushLock anchors is a new and effective surgical technique for the treatment of displaced tibial eminence fractures. By use of a high–bone density animal model, our results suggest that this suture bridge construct provides superior fixation with regard to ultimate failure load compared with standard screw fixation and suture fixation. Clinical Relevance The suture bridge technique provides another fixation option for displaced tibial eminence fractures with comparable, and in some instances superior, biomechanical properties to screw fixation and suture fixation.

The purpose of this study was to compare tibiofemoral (TF) kinematics and TF compressive stresses between single bundle- (SB-) and double bundle-ACL reconstruction (DB-ACLR) during simulated squatting. Twelve matched pairs of fresh frozen cadaver knees were utilized. A simulated squat through 100° of knee flexion was performed in the ACL-intact joint. The ACL was transected and SB- and DB-ACLR procedures were performed in one knee of each pair. The squat was repeated. Knee kinematics were measured using a motion tracking system and the TF compressive forces were measured using thin film pressure sensors. The posterior shifts of the tibia for SB- and DB-ACLR knees were significantly greater than the ACL-intact condition for knee flexion angles 0° to 40° (p.32). There were no significant differences between the two reconstruction conditions (p=.74). This study showed that there was no difference in the TF kinematics or compressive stresses between SB- and DB-ACLR, and only minor differences when compared to the intact state.

Success in sports is often defined by winning, which drives athletes to use performance-enhancing drugs (PEDs) to gain an advantage over opponents. Over the past 20 years, use of PEDs by Olympic and professional athletes has led to public discussion regarding potential negative health effects and ethical implications of their use. Unfortunately, PEDs are not isolated to professional athletes, as PED use in adolescents has increased dramatically. Many professional organizations, including the American Academy of Orthopaedic Surgeons (AAOS), have taken a stance against PED use in sports. The AAOS believes neither anabolic steroids nor their precursors should be used to enhance performance or appearance, and that these substances should be banned in all sports programs. Pediatricians and orthopedists are often the first physicians to see these young athletes. It is critical for these physicians to recognize the significance of the problem, have the knowledge to inform adolescents, dissuade them from future use, and provide viable alternatives for meeting performance goals.

Background: Quantifying changes in meniscal volume in vivo before and after partial meniscectomy (PM) could help elucidate the mechanisms involved in osteoarthritis development after meniscal injury and its surgical treatment. Purpose/Hypothesis: To determine whether quantitative magnetic resonance imaging (qMRI) can detect the immediate reduction in meniscal volume created by PM, while ruling out changes in unresected structures. We hypothesized that qMRI would be reliable for determining meniscal volume within the repeated images of unresected menisci. Additionally, we expected no significant difference in volume between the uninjured menisci of the injured knees and the same menisci of the uninjured knees. Study Design: Cohort study (Diagnosis); Level of evidence, 2. Methods: Ten subjects with meniscal tears were evaluated with 3-T MRI before and after arthroscopic PM. Manual segmentation was used to create models of the menisci and to determine the preoperative and postoperative meniscal volumes for each subject. The responsiveness and reliability of qMRI for determining meniscal volume in vivo were evaluated using these measurements. We expected a decrease in volume of the resected menisci, but not in the uninjured menisci, after surgery. Results: The mean preoperative volume of the injured menisci was significantly greater than the mean postoperative volume (2896 ± 277 vs 2480 ± 277 mm3; P = .000). There was no significant difference between the mean preoperative and postoperative volumes of the uninjured menisci (2687 ± 256 vs 2694 ± 256 mm3; P = 1.000). Conclusion: Manual segmentation demonstrated a significant reduction in the volume of the surgically resected menisci after PM, but no significant change in the volume of unresected meniscal tissue, indicating that the manual segmentation method is responsive. Clinical Relevance: This approach offers a novel, reliable method to study the relationship between the volume of meniscal tissue removed during PM and subsequent patient outcomes during long-term clinical studies.

The clumsy child may be clumsy for various reasons. The child may have a host of different athletic injuries that, although trivial, may cause him or her to limp or fall. These have to be ruled out and sought out. The unique physiology of children has to be considered in making the diagnosis. One is also obligated to rule out the other causes of clumsiness, rotational deformities, neurologic problems, or muscle diseases. And finally, one should not label the normal child who may not be a great athlete as clumsy or refer the child for unnecessary therapy or treatment.

This study aimed to evaluate sources of variability when the metatarsal-phalangeal (MTP) semiflexed radiographic technique is used to measure the tibiofemoral joint space width in the medial and lateral compartments of the knee. Three independent digital MTP radiographs were obtained from both knees of 9 participants. The joint space widths of both compartments of each knee were measured 3 times by 2 independent examiners. Intraclass correlation coefficients were high between repeated radiographs, between examiners, and within examiners (range, 0.91-0.98). These 3 error components accounted for 9% and 14% of the total variance for the medial and lateral compartments, respectively. The estimated SDs across radiographs for the medial and lateral compartments were 0.093 mm and 0.155 mm. The digital radiographic technique based on the MTP view is a simple and reliable technique for measuring the joint space width that can be readily used to track longitudinal changes in cartilage thickness after knee joint surgery.

Objective To study the effect of anterior cruciate ligament (ACL) injury on lubricin concentrations in synovial fluid (SF) and its correlation with time postinjury, inflammatory cytokines, lubricin-degrading enzymes, and SF proteoglycan content. Methods SF samples were obtained from both knees of 30 patients with unilateral ACL insufficiency, 32–364 days postinjury. Lubricin, inflammatory cytokines (interleukin-1β [IL-1β], tumor necrosis factor α [TNFα], and IL-6), and catabolic enzymes (procathepsin B and neutrophil elastase) were measured in SF from injured and contralateral (uninjured) joints, by enzyme-linked immunosorbent assay. Sulfated glycosaminoglycan (sGAG) levels in the SF were measured by Alcian blue binding assay. Results SF lubricin concentrations were significantly (P < 0.001) reduced at an early stage following ACL injury when compared with those in the contralateral joint. Within 12 months, the lubricin concentration in the injured knee (slope = 0.006, SE = 0.00010, P < 0.001) approached that in the contralateral knee, which did not change with time (slope = −0.0002, SE = 0.00050, P = 0.71). TNFα levels showed a significant negative relationship with log2 lubricin levels. IL-1β, TNFα, IL-6, procathepsin B, and neutrophil elastase concentrations in SF from injured knees were greater in samples from recently injured knees compared with those that were chronically injured. There were no detectable cytokines or enzymes in the SF of contralateral joints. Concentrations of sGAG were significantly (P = 0.0002) higher in the SF from injured knees compared with the contralateral joints. Conclusion The decrease in SF lubricin concentrations following ACL injury may place the joint at an increased risk of wear-induced damage as a consequence of lack of boundary lubrication, potentially leading to secondary osteoarthritis. The decrease in SF lubricin was associated with an increase in levels of inflammatory cytokines.

Many receptors located within the intra-articular knee structures contribute to the neuromuscular responses of the knee. The purpose was to compare the automatic postural response induced by a perturbation at the foot before and after an intra-articular injection of a local anesthetic (bupivicaine), after a saline (sham) injection, and after no intra-articular injection (control) in the knee.Muscle onset latencies and automatic response magnitudes for the vastus medialis, vastus lateralis, biceps femoris, medial hamstrings, tibialis anterior, and gastrocnemius were measured using electromyography (EMG) when anteriorly directed perturbations were applied to the feet of 30 subjects. All subjects then received a lidocaine skin injection followed by: an intra-articular bupivicaine injection (treatment group); an intra-articular saline injection (sham group); or no injection (control group), depending on their randomized group assignment. The perturbation tests were then repeated.Muscle onset latencies and automatic response magnitudes did not change as a result of the intra-articular injections. Latencies were significantly greater for the vastus medialis and vastus lateralis when compared to the medial hamstrings, biceps femoris and tibialis anterior (P0.001). Automatic response magnitudes for the tibialis anterior were significantly greater than those of the hamstrings, which were greater than those of the quadriceps (P0.001).There were no differences in muscle response when anteriorly directed perturbations were applied to the foot with or without an injection of local anesthetic in the knee. Intra-articular receptors were either unaffected by the anesthetic or the extra-articular receptors or receptors of the other joints were able to compensate for their loss.

Background The initial tension applied to an anterior cruciate ligament graft at the time of fixation modulates knee motion and the tibiofemoral compressive loads. Purpose To establish the relationships between initial graft tension, tibiofemoral compressive force, and the neutral tibiofemoral position in the cadaveric knee. Study Design Controlled laboratory study. Methods The tibiofemoral compressive forces and joint positions were determined in the anterior cruciate ligament-intact knee at 0°, 20°, and 90° of knee flexion. The anterior cruciate ligament was excised and reconstructed with a patellar tendon graft using graft tensions of 1, 15, 30, 60, and 90 N applied at 0°, 20°, and 90° of knee flexion. The compressive forces and neutral positions were compared between initial tension conditions and the anterior cruciate ligament-intact knee. Results Increasing initial graft tension increased the tibiofemoral compressive forces. The forces in the medial compartment were 1.8 times those in the lateral compartment. The compressive forces were dependent on the knee angle at which the tension was applied. The greatest compressive forces occurred when the graft was tensioned with the knee in extension. An increase in initial graft tension caused the tibia to rotate externally compared with the anterior cruciate ligament-intact knee (1.5° and 7.7° of external rotation when tensioned to 90 N at 0° and 90° of knee flexion, respectively). Increases in initial graft tension also caused a significant posterior translation of the tibia relative to the femur (0.9 and 5.3 mm of posterior translation when tensioned to 90 N at 0° and 90° of knee flexion, respectively). Conclusion Different initial graft tension protocols produced predictable changes in the tibiofemoral compressive forces and joint positions. Clinical Relevance The tibiofemoral compressive force and neutral joint position were best replicated with a low graft tension (1-15 N) when using a patellar tendon graft.

Purpose: To study the use of a methylprednisolone taper (Medrol Dosepak; Pfizer, New York, NY) short-term oral corticosteroid treatment modality by sports medicine physicians; included is discussion on indications, perceived efficacy, and complications. Methods: A survey specific to Medrol Dosepak (MDP) use was mailed to all members of the Arthroscopy Association of North America (AANA) and the American Orthopedic Society for Sports Medicine (AOSSM). Surveys were collected and data were collated and analyzed. Results: Total response rate was 41% (1,290/3,167), US response rate 43% (1,247/2,906), and international response rate 16% (43/261). Prescribing of MDP for sports injuries was significantly associated with average patient age ≤40 years (χ square; P = .001), but it was not associated with years in practice or patients seen per year. It was found that 47% of members (603/1,290) prescribe MDP. Postinjury disease was the most common indication. The most frequent complication was glucose intolerance (37%; 222/603). Of members who prescribe MDP, 8.5% (51/603) reported that they had seen 101 total cases of osteonecrosis, predominantly in the hip. Results revealed that 52% of members (672/1,290) do not prescribe MDP. The most frequent reasons for not prescribing included fear of osteonecrosis (30%; 201/672), fear of complications in general (27%; 183/672), lack of proven efficacy (27%; 180/672), and fear of malpractice (4.5%; 30/672). Of nonprescribing members (171/672), 25% had seen 500 cases of osteonecrosis, most often in the hip. Conclusions: The responding membership of AANA and AOSSM is evenly split regarding MDP use. Average patient age ≤40 years was associated with a greater likelihood that MDP would be prescribed for sports injuries. Postinjury disease is the most common indication; lack of proven efficacy and osteonecrosis are deterrents to prescription. Level of Evidence: Level V, expert opinion.

Knee injuries continue to be an increasingly common and highly visible problem presenting to the sports medicine physician. The physicians who handle knee injuries will be challenged by patients, coaches, trainers, business agents, the press, and family members with an ever-increasing sophistication of medical knowledge. An understanding of the underlying structure and function of the commonly injured ligaments, menisci, and the patellofemoral joint is discussed. Diagnosis by physical examination is encouraged. Conservative and surgical treatment options are reviewed as are the considerations involved in deciding the time to return to sports.

The initial fixation properties of bioresorbable polylactic acid (PLA) interference screws designed for anterior cruciate ligament reconstruction were evaluated using an in vitro bovine model. The surgical technique of interference screw fixation of the bone-patellar tendon-bone autograft complex performed clinically was reproduced in an adult bovine model. The reconstructed knee was tested oriented in 30 degrees of flexion to allow examination of the femoral and tibial fixation properties simultaneously. This model examined the initial fixation strength between PLA and metal interference screws as well as a partially degraded PLA implant. Data from this in vitro model indicate that PLA interference screws can provide similar initial fixation at both time 0 and after degradation for up to 28 days compared with metal interference screws for bone-tendon-bone ACL reconstructions.