Search

Background: Patellar tendon ruptures have a reported incidence of 0.68 per 100,000 person-years in the general population. The epidemiology of surgically treated patellar tendon ruptures in the US military has yet to be reported, which would provide opportunity for identification of risk factors for these otherwise healthy and active patients. Purpose: To determine the incidence of patellar tendon rupture in the Military Health System (MHS) population and to analyze demographic patterns, surgical fixation methods, and rerupture rates. Study Design: Case-control study; Level of evidence, 3. Methods: We utilized the MHS Data Repository (MDR) to identity active-duty military servicemembers surgically treated for patellar tendon rupture between 2010 and 2015. Records were reviewed for demographic information, injury characteristics, fixation technique, and occurrence of rerupture. Risk factors for rupture were calculated using Poisson regression based on population counts and demographic data obtained in the MDR. Risk factors for rerupture and return to duty were analyzed via univariate analysis and multivariate regression. Results: A total of 504 operatively treated primary patellar tendon repairs in 483 patients were identified, with an overall incidence of 6 per 100,000 person-years. Mean age was 33.6 years (range, 17-54 years) and 98% of patients were male. Fixation method was 81% bone tunnels and 7% suture anchors, and 12% were unknown. Black race had a higher relative rate ratio for rupture compared with the race categories White (9.21; P < .0001) and Other (3.27; P < .0001). The rupture rate was higher in 35- to 44-year-old patients compared with those aged 18 to 24 years ( P < .0001), 25 to 34 years ( P < .0001), and 45 to 64 years ( P = .004). Return to full previous level of activity occurred in 75.8% of patients, 14.6% returned to activity with limitations, and 9.5% were medically separated. The rerupture rate was 3%. Fixation method, tobacco usage, body mass index, and race were not significant risk factors for rerupture. Conclusion: The incidence of patellar tendon rupture in the US military population is substantially higher than has been reported in the civilian population. Among military personnel, men, Black servicemembers, and those aged 35 to 44 years were at highest risk for patellar tendon rupture. Three-quarters of patients were able to return to full activity without limitations. The rerupture rate was low and unaffected by fixation method.

Background: The preferred patient-reported outcome measure for the assessment of shoulder conditions continues to evolve. Previous studies correlating the Patient-Reported Outcomes Measurement Information System (PROMIS) computer adaptive tests (CATs) to the American Shoulder and Elbow Surgeons (ASES) score have focused on a singular domain (pain or physical function) but have not evaluated the combined domains of pain and physical function that compose the ASES score. Additionally, previous studies have not provided a multivariable prediction tool to convert PROMIS scores to more familiar legacy scores. Purpose: To establish a valid predictive model of ASES scores using a nonlinear combination of PROMIS domains for physical function and pain. Study Design: Cohort study (Diagnosis); Level of evidence, 3. Methods: The Military Orthopaedics Tracking Injuries and Outcomes Network (MOTION) database is a prospectively collected repository of patient-reported outcomes and intraoperative variables. Patients in MOTION research who underwent shoulder surgery and completed the ASES, PROMIS Physical Function, and PROMIS Pain Interference at varying time points were included in the present analysis. Nonlinear multivariable predictive models were created to establish an ASES index score and then validated using “leave 1 out” techniques and minimal clinically important difference /substantial clinical benefit (MCID/SCB) analysis. Results: A total of 909 patients completed the ASES, PROMIS Physical Function, and PROMIS Pain Interference at presurgery, 6 weeks, 6 months, and 1 year after surgery, providing 1502 complete observations. The PROMIS CAT predictive model was strongly validated to predict the ASES (Pearson coefficient = 0.76-0.78; R2 = 0.57-0.62; root mean square error = 13.3-14.1). The MCID/SCB for the ASES was 21.7, and the best ASES index MCID/SCB was 19.4, suggesting that the derived ASES index is effective and can reliably re-create ASES scores. Conclusion: The PROMIS CAT predictive models are able to approximate the ASES score within 13 to 14 points, which is 7 points more accurate than the ASES MCID/SCB derived from the sample. Our ASES index algorithm, which is freely available online ( https://osf.io/ctmnd/ ), has a lower MCID/SCB than the ASES itself. This algorithm can be used to decrease patient survey burden by 11 questions and provide a reliable ASES analog to clinicians.

CASE A 21-year-old man sustained a closed glenohumeral fracture/dislocation as a pedestrian struck by a motor vehicle. He was treated nonoperatively and developed severe post-traumatic heterotopic ossification (HO) with near-complete shoulder ankylosis. We present our technique for safe surgical excision. CONCLUSIONS Excision led to improvements in motion and quality of life at 1 year postoperatively. Recommendations for successful HO excision around the shoulder include excision after at least 180 days, appropriate preoperative imaging to include cross-sectional imaging and a 3D model, intraoperative fluoroscopy, well-serviced instruments, preparation for iatrogenic fracture and/or neurovascular injury, meticulous hemostasis, postoperative HO prophylaxis, immediate postoperative therapy, and involvement of a multidisciplinary team.

Despite the advent of sutureless technology, knot tying remains an important skill for any arthroscopist. When one is choosing which knot to tie, there are a variety of options, with each possessing its own inherent strengths and weaknesses. The West Point knot is a sliding-locking arthroscopic knot that is relatively easy to learn and has excellent knot security. This article details the appropriate manner in which to tie this knot.

Background:Shoulder instability is a topic of significant interest within the sports medicine literature, particularly regarding recurrence rates and the ideal treatment indications and techniques. Little has been published specifically addressing the occupational implications of symptomatic recurrent shoulder instability.Hypothesis:Previous arthroscopic repair will continue to be a significant predisposing factor for recurrent instability in a young, active population, and that recurrent instability may have a negative effect on college graduation and postgraduate occupational selection.Study Design:Case series.Level of Evidence:Level 4.Methods:We conducted a retrospective review of approved medical waivers for surgical treatment of anterior shoulder dislocation or instability prior to matriculation at the US Military Academy or the US Naval Academy for the graduating classes of 2010 to 2013. Statistical analysis was performed to determine the incidence and risk factors for recurrence and to determine the impact on graduation rate and occupation selection.Results:Fifty-nine patients were evaluated; 34% developed recurrent anterior instability. Patients with previous arthroscopic repair had a significantly higher incidence of recurrence (38%, P = 0.044). Recurrent shoulder instability did not significantly affect graduation rates or self-selected occupation ( P ≥ 0.05).Conclusion:There is a significant rate of recurrent shoulder instability after primary surgical repair, particularly among young, active individuals. In addition, arthroscopic repair resulted in a significantly higher recurrence rate compared with open repair in our population. Surgical repair for shoulder instability should not necessarily preclude young individuals from pursuing (or being considered for) occupations that may place them at greater risk of recurrence.Clinical Relevance:The risk of recurrent instability is greater than the rate typically described, which may suggest that some subpopulations are at greater risk than others. A unique data point regarding instability is the effect on occupation selection.

Background: Pectoralis major tendon ruptures are commonly described as rare injuries affecting men between 20 and 40 years of age, with generally excellent results after surgical repair. However, this perception is based on a relatively small number of case series and prospective studies in the orthopaedic literature. Purpose: To determine the incidence of pectoralis major tendon ruptures in the active-duty military population and the demographic risk factors for a rupture and to describe the outcomes of surgical treatment. Study Design: Case control study; Level of evidence, 3. Methods: We utilized the Military Health System Data Repository (MDR) to identify all active-duty military personnel surgically treated for a pectoralis major tendon rupture between January 2012 and December 2014. Electronic medical records were searched for patients’ demographic information, injury characteristics, and postoperative complications and outcomes. Risk factors for a rupture were calculated using Poisson regression, based on population counts obtained from the MDR. Risk factors for a postoperative complication, the need for revision surgery, and the inability to continue with active duty were determined using univariate analysis and multivariate logistic regression. Results: A total of 291 patients met inclusion criteria. The mean patient age was 30.5 years, all patients were male, and the median follow-up period was 18 months. The incidence of injuries was 60 per 100,000 person-years over the study period. Risk factors for a rupture included service in the Army, junior officer or junior enlisted rank, and age between 25 and 34 years. White race and surgery occurring >6 weeks after injury were significant risk factors for a postoperative complication. Among the 214 patients with a minimum of 12 months’ clinical follow-up, 95.3% were able to return to military duty. Junior officer/enlisted status was a significant risk factor for failure to return to military duty. Conclusion: Among military personnel, Army soldiers and junior officer/enlisted rank were at highest risk of pectoralis major tendon ruptures, and junior personnel were at highest risk of being unable to return to duty after surgical treatment. Although increasing time from injury to surgery was not a risk factor for treatment failure or inability to return to duty, it did significantly increase the risk of a postoperative complication.

Background: Although many authors report on acute injuries and chronic injuries in the orthopaedic literature, the actual terms are seldom explicitly defined. Hypothesis: Much of the literature pertaining to sports injuries that are acute or chronic does not define these terms. It is believed that definitions will provide clarity and specificity in future literature. Study Design: Systematic review. Methods: A systematic review of 116 articles was conducted to determine whether and how the terms acute and chronic were defined as they pertain to several commonly treated conditions: Achilles tendon rupture, distal biceps tendon rupture, pectoralis major tendon rupture, anterior cruciate ligament (ACL) tear, anterior shoulder instability, and acromioclavicular (AC) joint dislocation. Articles were isolated from various databases and search engines by use of keywords to identify relevant literature. Results: This study determined that the terms acute and chronic for each injury are defined, respectively, as follows: Achilles tendon rupture: 4 weeks; distal biceps tendon rupture: 12 weeks; pectoralis major tendon rupture: 6 weeks; ACL tear: 6 months; anterior shoulder instability: 6 months; AC joint dislocation, 6 weeks. Conclusion: The current literature varies greatly in defining the terms acute and chronic in common sports injuries. The vast majority of authors imply these terms, based on the method of their studies, rather than define them explicitly. Injuries involving tendons showed greater consistency among authors, thus making a definition based on consensus easier to derive. The literature on ACL and shoulder instability in particular showed great variability in defining these terms, likely representing the more complex nature of these injuries and the fact that timing of surgery in the majority of patients does not particularly affect the complexity of the surgical approach and treatment. Clinical Relevance: Defining injuries as acute or chronic is clinically relevant in many cases, particularly concerning tendon injuries, where these terms have implications regarding the anatomic pathologic changes and tissue quality, which may necessitate augmentation and alter the initial surgical plan. In cases where these terms are less pertinent to operative treatment considerations, they bring clarity to the discussion of the acuity of the injury (as it pertains to time from insult).

Background: The neurovascular structures of the proximal arm may be at risk for iatrogenic injury during open subpectoral biceps tenodesis (OSPBT). Purpose: To define the anatomic relationships and at-risk structures during OSPBT and to quantify the effect of arm rotation on the position of the musculocutaneous nerve. Study Design: Descriptive laboratory study. Methods: The OSPBT approach was performed in 17 unembalmed cadaveric upper extremities. The tenodesis site was inferior to the bicipital groove and positioned so the musculotendinous portion of the long head of the biceps rested at the inferior border of the pectoralis major. A meticulous dissection identified the brachial artery, deep brachial artery, cephalic vein, brachial vein, medial brachial cutaneous nerve, medial antebrachial cutaneous nerve, intercostal brachial cutaneous nerve, musculocutaneous nerve, axillary nerve, median nerve, and radial nerve. Superficial structures were measured from the superior and inferior aspects of the incision, and deep structures were measured from the tenodesis site and nearest retractor. The musculocutaneous nerve was measured with the arm in neutral, internal, and external rotation. Results: The musculocutaneous nerve was 10.1 mm (range, 6-18 mm) medial to the tenodesis location and 2.9 mm (range, 1-6 mm) medial to the medially placed retractor in neutral arm position. The radial nerve and deep brachial artery were 7.4 mm (range, 2-12 mm) and 5.7 mm (range, 1-10 mm) deep to the medially placed retractor, respectively. With the arm internally rotated to 45°, the musculocutaneous nerve was 8.1 mm from the tenodesis site, compared with 19.4 mm with the arm 45° externally rotated ( P = .009). The median nerve, brachial artery, and brachial vein were >2.5 cm from the tenodesis site and nearest retractor during deep dissection. Conclusion: The musculocutaneous nerve, radial nerve, and deep brachial artery are within 1 cm of the standard medial retractor. External rotation of the arm moves the musculocutaneous nerve 11.3 mm further away from the tenodesis site compared with the internally rotated position. Clinical Relevance: The musculocutaneous nerve, radial nerve, and deep brachial artery course in close proximity to the operative field and are therefore at risk during OSPBT. Limiting the use of medial retraction and placement of the arm in an externally rotated position will minimize neurovascular injury.

Modern meniscal repair incorporates multiple techniques and adjunctive measures. The classic inside-out repair remains the gold standard and is most appropriate for a bucket-handle type tear of the medial or lateral meniscus. The all-inside technique has gained in popularity recently and has outcomes that approach those of the inside-out repair with decreased morbidity but increased cost. The choice of this technique is most appropriate for small tears requiring few sutures to repair. Outside-in repair can also be employed and is preferred for anterior horn tears. Surgeons may use a hybrid technique that incorporates all techniques in some challenging cases. Meniscal debridement is used for degenerative tears that are not amenable to repair. Meniscal transplantation is an option for symptomatic meniscal deficiency in young, active patients. This article discusses the technical considerations for meniscal debridement, repair, and transplantation.

Summary: Cartilage injuries of the patellofemoral joint present a difficult challenge owing to the unique anatomy and high shear forces. Active duty military personnel commonly present with cartilage injuries of the patella and trochlea owing to acute trauma or chronic repetitive injury. The initial treatment for patellofemoral chondral injury is nonoperative modalities to include: rest, activity modification, anti-inflammatory medication, and physical therapy. Physical therapy predominantly focuses on strengthening the vastus medialis obliquus to improve patellofemoral alignment. Reconstructive cartilage procedures like fresh osteochondral allograft transplant and autologous chondrocyte implantation are used to restore articular congruity and minimize symptoms when nonoperative modalities and common first-line reparative techniques fail. Although there is currently no evidencebased algorithm for the management of cartilage lesions of the patellofemoral joint, there are trends in treatment that help guide the surgeon. The successful outcome of treatment for cartilage lesions depends on recognizing and addressing concomitant pathology with proximal or distal realignment and patellar unloading procedures. Outcomes also depend on appropriate patient selection with his/her commitment to an extended period of rehabilitation and the ability to modify their activities. The active duty patient does not always have the ability to participate in an extended period of rehabilitation and must be treated with the best treatment option that allows an effective return to duty. Therefore, the purpose of this article is to review the standard treatment options for chondral lesions of the patellofemoral joint and our preferred treatment options in the active duty patient.

Summary: Articular cartilage lesions of the femoral condyles are common and have limited healing capacity. The goal of surgical management is to relieve pain and mechanical symptoms, and hopefully slow the progression of osteoarthritis. Numerous surgical procedures have been described to include chondroplasty, microfracture, autologous chondrocyte implantation, autologous osteochondral transfer, allograft osteochondral transplantation, and fragment fixation. Each technique is distinguished by number of procedures required, expense, donor-site morbidity, risks of allograft tissues, and rehabilitation requirements. To maximize the surgical outcomes, it is imperative to treat any concomitant pathology to include mechanical malalignment, ligamentous instability, and/or meniscal deficiency. Several treatment algorithms have been proposed to guide management of symptomatic, focal chondral injuries of the femoral condyles. Algorithm decisions are based on lesion location, size, patient activity level, and earlier treatment. This article reviews the treatment considerations of the various techniques and the published results and illustrative case examples.

Critical evaluations of anterior cruciate ligament (ACL) reconstruction failure modes have shown that the most common cause for failure is aberrant femoral tunnel placement. Regardless of the surgical reconstruction technique, it is imperative to have a thorough understanding of the anatomy and function of the anteromedial (AM) and posterolateral (PL) bundles of the native ACL to successfully restore the stability and motion of the injured knee. Similar to the observation that anatomic reduction is critical to successful fracture management, ACL reconstruction techniques must focus on restoring the normal anatomy of the ACL. This article reviews the anatomy of the AM and PL bundles of the ACL, including landmarks for identifying their femoral and tibial footprints.

Background context Untreated osteoporosis causes decreased bone mineral density, which predisposes to fragility fractures. Low-energy vertebral compression fractures are the most common type of osteoporotic fragility fracture. Prior studies have shown that only one-quarter of patients diagnosed with an osteoporotic fracture are referred or treated for osteoporosis. Purpose To identify the rate of therapeutic interventions for patients aged 50 years and older within a capitated population who sustained low impact vertebral compression fractures over a 6-month period. Study design/setting Retrospective observational study. Patient sample The reports of all imaging studies of the chest, abdomen, and spine taken from July to December 2002 within a large military health-care system were queried on the Composite Health Computer System (CHCS). The sample included patients 50 years or older who had a low-energy vertebral compression fracture. Outcome measures The computerized medical records were examined for osteoporotic medication prescriptions, referrals to endocrinology, and to dual-energy X-ray absorptiometry (DEXA) scans. These results were compared with results obtained from a similar study on osteoporotic distal radius fractures. Results The records of 156 patients (average age: 77.3 y; 78 women, 78 men) meeting the inclusion criteria were analyzed to determine what proportion was followed-up with osteoporosis interventions. Within 1 year after the fracture, 39% (37 females, 24 males) had undergone a DEXA scan, 35% (37 females, 18 males) had been referred to endocrinology, 38% (47 females, 12 males) were receiving active osteoporosis treatment, and 51% (55 females, 25 males) were receiving any form of osteoporosis-directed medication. The rate of medical intervention was similar to the rate of intervention after distal radius fragility fractures (n=111; 30% active medication; 47% any osteoporosis medication) (p>.21). The rate of all interventions was significantly greater for women than men. Conclusions Although the likelihood of intervention is slightly greater after vertebral compression fractures than for distal radius fractures, orthopedic surgeons, emergency room physicians, and primary care providers continue to miss opportunities, especially in males, to diagnose and/or initiate active therapeutic interventions for osteoporosis in patients presenting with osteoporosis-related fragility fractures.

As our patients become more physically active at all ages, the incidence of injuries to articular cartilage is increasing and is causing patients significant pain and disability at a younger age. The intrinsic healing response of articular cartilage is poor, because of its limited vascular supply and capacity for chondrocyte division. Nonsurgical management for the focal cartilage lesion is successful in the majority of patients. Those patients that fail conservative management may be candidates for a cartilage reparative or reconstructive procedure. The type of treatment available depends on a multitude of lesion-specific and patient-specific variables. First-line therapies for isolated cartilage lesions have demonstrated good clinical results in the correct patient but typically repair cartilage with fibrocartilage, which has inferior stiffness, inferior resilience, and poorer wear characteristics. Advances in cell-based cartilage restoration have provided the surgeon a means to address focal cartilage lesions utilizing mesenchymal stem cells, chondrocytes, and biomimetic scaffolds to restore hyaline cartilage.

Purpose: To assess the intraobserver reliability and prognostic value of magnetic resonance arthrography (MRA) on the basis of postoperative outcome measures following arthroscopic acetabular labral debridement (partial limbectomy). Methods: Between January 1999 and November 2000, 24 patients (13 females, 11 males) with an average age of 37.1 years (range, 21 to 56 years) underwent hip arthroscopy for the treatment of presumed acetabular labral tears. All patients underwent preoperative MRA and/or magnetic resonance imaging (MRI); images were evaluated by a single musculoskeletal radiologist on 2 independent occasions. Hip arthroscopy was performed on all patients. Outcomes were assessed by means of the Modified Harris Hip Score (MHHS) and the Short Form-36 (SF-36) questionnaires, which were completed by patients an average of 24.1 months (range, 12 to 55 months) postoperatively. The accuracy of the initial read, as well as the prognostic value of the Czerny MRA classification system for stage II (intrasubstance tears) and stage III (complete avulsions) acetabular labral tears, was assessed. Results: Twenty-two of 23 tears (96%) were detected on the initial read. On the basis of intraoperative findings, 1 false-positive MRA, 1 false-negative MRA, and 1 incident of MRA overstaging were reported. On repeat interpretation, 23 of 23 (100%) tears were identified, and intraobserver reliability for recording the presence of a tear was excellent (kappa coefficient=0.96). No difference was noted in outcomes between patients with or without arthroscopic evidence of chondromalacia (all P > .29), or between patients older or younger than 30 years (all P > .34). Likewise, no difference in outcome was seen between 15 patients with Czerny stage II tears revealed on MRA versus 9 patients with Czerny stage III tears (all P > .79). Conclusions: MRA is sensitive and accurate for the detection of acetabular labral tears, with excellent intraobserver reliability. Arthroscopic partial limbectomy is successful in two thirds of patients. Patients with Czerny stage II and III tears do not appear to have significantly different outcomes following arthroscopic labral debridement. Level of Evidence: Level IV, prognostic case series.

Arthroscopy has become an invaluable tool for addressing elbow pathology in young active patients. The surgical indications for elbow arthroscopy are evolving, but our primary indication has been the treatment of lateral epicondylitis. While, the vast majority of patients with “tennis elbow” respond to nonoperative therapy, arthroscopic release of the extensor carpi radialis brevis (ECRB) can be a successful means of treating recalcitrant cases. Surgical treatment for recalcitrant lateral epicondylitis provides good results for pain relief and return to function. Arthroscopy appears to combine the best attributes of the earlier return to activity seen with percutaneous procedures and decreased recurrence rates demonstrated with open procedures. In contrast to open surgical management, arthroscopy affords the surgeon an opportunity to address intra-articular pathology which may be preventing the injured athlete’s return to the playing field. This article describes the indications and surgical technique for arthroscopic ECRB release in young athletes.

Background context Intradiscal electrothermal therapy (IDET) is a new treatment option for chronic discogenic low back pain that is minimally invasive and has demonstrated success rates equal to or better than those for spinal fusion at short-term follow-up. Purpose To report our experience with IDET in the management of chronic discogenic low back pain in active-duty soldiers. Study design/setting Consecutive case series at a US Army medical center. Outcome measures The primary outcome measured was a reported 50% or greater reduction in pain at latest follow-up. Additional outcomes measured included analog pain scores, satisfaction, complications, duty status and subsequent spinal surgery. Methods Between 1999 and 2001, 41 active-duty soldiers (34 men, 7 women) underwent IDET for chronic discogenic low back pain unresponsive to nonoperative therapy. Data were collected through clinic chart review and follow-up questionnaires. Success was defined as a stated “50% decrease in pain” from baseline. Results During the study period, 36 of 41 patients underwent a single trial of IDET, and the remaining 5 underwent two trials of IDET. Only the results of the 36 patients who underwent one trial of IDET were used for statistical analysis. All 36 patients were available for follow-up at 6 months, whereas only 31 patients (86%) were reached for final follow-up (average, 29.7 months; range, 24 to 46). The success rate was 47% (17 of 36) at 6 months and 16% (5 of 31 patients) at latest follow-up. Although overall success rates were low, 20 of 31 soldiers (65%) had a persistent decrease in their analog pain score (average decrease of 2.5±1.6 on a 10-point scale), with 52% having 2-point or greater decrease. Nineteen of 31 soldiers (61%) were still on active duty at a minimum of 24 months after IDET. There were five transient complications (16%) from IDET, all reported within the first month. Seven of 31 soldiers (23%), all male, went on to spinal surgery within 24 months of failed IDET. Conclusions IDET is not a substitute for spinal fusion in the treatment of chronic discogenic low back pain in active-duty soldiers. Our reasonable early results diminished with time and up to 20% of patients report worsening of baseline symptoms at final follow-up. IDET will prove its role in the treatment of chronic discogenic low back pain as more outcome data are obtained, but for now we consider it, at best, an antecedent rather than alternative to spinal fusion.

Meniscal allograft transplantation is a technically demanding procedure that is useful to improve patient satisfaction after total or subtotal meniscectomy. While not yet shown to be chondroprotective, it reliably improves patient subjective outcome measures over the short- to midterm follow-up period. Key factors to consider to improve outcomes include the alignment of the lower limb, the degree of cartilage wear based on the Outerbridge scale, and graft factors such as size, method of preservation, and method of fixation. Patient factors such as excessive body mass index and smoking may be relative contraindications to the procedure. Staged procedures such as high tibial osteotomy or distal femoral osteotomy may be indicated to ensure maximum outcome of the procedure. Grafts may be fashioned using bone plugs for each root, a bone bridge containing both roots, or may use soft tissue only. Open and arthroscopic techniques of meniscus transplant have been used. The most common ligament reconstruction and meniscus allograft combination has been an ACL reconstruction in conjunction with medial meniscal allograft transplantation. Its use in conjunction with the treatment of the multiple ligament-injured knee is limited to very specific cases, and little clinical evidence outside of case reports has been published to guide decision-making in this challenging treatment environment associated with such major knee injuries.

The goal of this study was to document the incidence of anterior cruciate ligament (ACL) tears and possible risk factors for these injuries in a large population of young, athletic subjects. The authors retrospectively reviewed the US Naval Academy’s database of midshipmen admitted in 1999 and 2000 (n = 2,345) and prospectively followed until graduation 4 years later or disenrollment. Excluded were 658 who had a history of preadmission ACL injury or surgery, those without initial radiographs or documented baseline height and weight, or those who had documented contact ACL injuries. Therefore, 1,687 subjects comprised the study group. Standard radiographic measurements, including condylar width, notch width, and femoral notch width index (notch width divided by condyle width), were obtained for all subjects. Statistical analyses were used to determine differences between injured and uninjured subjects. The overall incidence of non-contact ACL injury was 2.9% (37 men, 12 women). The average BMI was 25.6 and 24.4 kg/m2 for the injured and uninjured groups, respectively (P

Stress-related changes and fractures in the foot are frequent in runners. However, the causative factors, including anatomic and kinematic variables, are not well defined. Footwear choice has also been implicated in contributing to injury patterns with changes in force transmission and gait analyses reported in the biomechanical literature. Despite the benefits of footwear, there has been increased interest among the running community in barefoot running with proposed benefits including a decreased rate of injury. We report 2 cases of metatarsal stress fracture in experienced runners whose only regimen change was the adoption of barefoot-simulating footwear. One was a 19-year-old runner who developed a second metatarsal stress reaction along the entire diaphysis. The second case was a 35-year-old ultra-marathon runner who developed a fracture in the second metatarsal diaphysis after 6 weeks of use of the same footwear. While both stress injuries healed without long-term effects, these injuries are alarming in that they occurred in experienced male runners without any other risk factors for stress injury to bone. The suspected cause for stress injury in these 2 patients is the change to barefoot-simulating footwear. Runners using these shoes should be cautioned on the potential need for gait alterations from a heel-strike to a midfoot-striking pattern, as well as cautioned on the symptoms of stress injury.

Background: Recent military conflicts have resulted in numerous extremity injuries requiring complex orthopaedic reconstructive procedures, which begin with a thorough debridement of all contaminated and necrotic tissue in the zone of injury. The site of injury is also the site of healing, and we propose that debrided muscle tissue contains cells with robust reparative and regenerative potential. Methods: Debrided muscle from soldiers who had sustained traumatic open extremity injuries was collected during surgical debridement procedures at Walter Reed Army Medical Center. With modifications to a previously described stem-cell-isolation protocol, mesenchymal progenitor cells were harvested from traumatized muscle, enriched, expanded in culture, and exposed to induction media for osteogenesis, adipogenesis, and chondrogenesis. Results: The isolated mesenchymal progenitor cells stained positive for cell-surface markers (CD73, CD90, CD105), which are characteristic of adult human mesenchymal stem cells. Histological identification of lineage-specific markers demonstrated the potential of these cells to differentiate into multiple mesenchymal lineages. Reverse transcription-polymerase chain reaction analysis confirmed multilineage mesenchymal differentiation at the gene-expression level. Conclusions: To our knowledge, the present report provides the first description of mesenchymal progenitor cell isolation from traumatized human muscle. These cells may play an integral role in tissue repair and regeneration and merit additional investigation as they could be useful in future cell-based tissue-engineering strategies. Clinical Significance: Mesenchymal progenitor cells isolated from war-traumatized tissues have the potential for applications in cell-based tissue engineering. Elucidating the cellular mechanisms regulating their differentiation activities may lead to the development of novel treatments for musculoskeletal trauma and pathological healing responses, such as heterotopic ossification.

Introduction Subpectoral biceps tenodesis using an interference screw is frequently used to treat biceps-related shoulder pain. Limited reports assessing complications from this procedure describe persistent bicipital pain and failure of fixation as the most common, but still infrequent complications. We believe that with increased use of the subpectoral biceps tenodesis technique more complications may become evident. The purpose of this study is to provide the first anatomic description of at-risk structures during subpectoral tenodesis. Methods The subpectoral biceps approach described by Mazzocca et al (2005) was performed in 17 upper limbs using a standard incision placed in the medial one-third of the arm, centered over the pectoralis tendon. As originally described, a blunt Chandler was positioned on the medial aspect of the humerus to retract the coracobrachialis and short head of the biceps. The location of the tenodesis was consistently referenced at the medial border of the biceps and inferior aspect of the pectoralis tendon. All important anatomic structures were identified, including the cephalic vein, medial brachial cutaneous nerve of the arm and forearm, intercostal brachial cutaneous nerve, musculocutaneous nerve, axillary nerve, brachial artery and vein, radial nerve, and deep brachial artery. Superficial structures were measured relative to the skin incision and deep structures were measured from the tenodesis site. Results Seventeen upper extremity dissections (9 right, 8 left) were performed in 9 cadavers (6 males and 3 females). The cephalic vein was 9.2 mm ± 6.1 mm and 13.7 mm ± 5.8 mm lateral to the superior and inferior margins of the incision, respectively. The medial brachial cutaneous nerve of the arm, medial brachial cutaneous nerve of the forearm and intercostal brachial cutaneous nerves were not at risk during superficial dissection. The musculocutaneous nerve was 10.1 mm ± 3.2 mm medial to the tenodesis location and 2.94 mm ± 1.4 mm medial to the medially placed retractor. In internal rotation the musculocutaneous nerve was 8.1 mm ± 3.3 mm from the tenodesis site compared to 19.4 mm ± 8.2 mm in external rotation (p Conclusion This study represents the first anatomic assessment of at-risk structures in subpectoral biceps tenodesis. The proximity of the musculocutaneous nerve to the tenodesis site and medial retractor make this a particularly vulnerable structure. External rotation of the arm moves the nerve 11.3 mm away from the tenodesis site and this maneuver should be applied during deep dissection. Additionally, although not previously described as a potential complication, the proximity of the leading edge of the medial retractor to the radial nerve and deep brachial artery is important and should be considered when placing this retractor. With increased acceptance of this procedure, more adverse outcomes related to damage of surrounding neurovascular structures are plausible but may be prevented by an improved understanding of the applied anatomy.