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Introduction Virtual planning for shoulder arthroplasty using preoperative computed tomography (CT) has been gaining popularity, and it is imperative for surgeons to recognize any differences in measurements that may exist amongst software platforms. The purpose of this study is to compare measurements of glenoid version, inclination, and humeral head subluxation between a manual approach and two varying automated software platforms using either a best-fit sphere technique (Wright-Medical BLUEPRINT) or an anatomic landmarks technique (Materalise SurgiCase). Methods A case control study of 289 CT images from patients preoperatively planned for a total shoulder arthroplasty or reverse shoulder arthroplasty using SurgiCase (v3.0.110.5) were also successfully analyzed by BLUEPRINT (v2.1.6). Glenoid version, inclination, and subluxation were measured manually in a blind fashion by two separate investigators using axial and coronal images oriented to the scapular plane; interobserver and intraobserver reliabilities were measured using intraclass correlation coefficients (ICCs). Concordance correlation coefficients (CCCs), mean differences, and clinically relevant agreement in measurements between the software platforms and with the manual technique were compared. The impact of greater glenoid retroversion on the differences in measurements between the software platforms was further studied by correlation analysis. Results The mean differences between SurgiCase and BLUEPRINT were + 0.5° for glenoid inclination (P = .064; CCC = 0.84), -0.9° for glenoid version (P Conclusion The SurgiCase and BLUEPRINT preoperative planning software yield clinically similar measurements for glenoid version, inclination, and subluxation. The degree of glenoid retroversion does not impact the variability of inclination or version between the landmark and best-fit sphere software techniques. Compared to the 2D manual technique, both 3D software programs reported greater inferior inclination, retroversion, and posterior subluxation. Level of evidence Level III; Retrospective Diagnostic Study

Background: Core muscle injury (CMI), often referred to as a sports hernia, is a common cause of groin pain in athletes characterized by concomitant injury to the insertion of the adductor longus and the rectus abdominis muscles. Currently, the literature on CMI is sparse with no standardized physical examination tests used in the diagnosis of this type of injury. Purpose: To determine the diagnostic accuracy of various physical examination tests in the diagnosis of CMI. Study Design: Cohort study (Diagnosis); Level of evidence, 3. Methods: A consecutive series of patients evaluated by the senior author with symptoms consistent with CMI were included. Four physical examination tests were routinely performed in these patients by the senior author and were noted in each patient’s chart as positive or negative: (1) pain with resisted cross-body sit-up in figure-of-4 position, (2) pain with straight-leg sit-up, (3) pain with resisted hip flexion in external rotation (external rotation Stinchfield test), and (4) the presence of an adductor contracture. CMI was independently diagnosed by a reference standard (magnetic resonance imaging [MRI]). All MRI scans were read by a musculoskeletal fellowship-trained radiologist. The sensitivity and specificity of each physical examination test alone and in combination were calculated based on this reference standard. Results: A total of 81 patients were included in this study. MRI was positive for a CMI in 39 patients (48%) overall. Both the cross-body sit-up test and the presence of an adductor contracture were found to have a sensitivity of 100% (specificity, 3% for both). The external rotation Stinchfield test was found to have the highest specificity of 60% (sensitivity, 15%). The sensitivity of all 4 physical examination tests in combination was found to be 100% (specificity, 0%). Conclusion: Certain physical examination maneuvers can be used to assist in the diagnosis of a CMI. The cross-body sit-up test and the presence of an adductor contracture are highly sensitive but nonspecific tests for CMI and therefore should be used in conjunction with diagnostic imaging before deciding on an appropriate treatment course.

Tackle football is a uniquely American sport that carries with it a great risk to the developing musculoskeletal system of the prepubescent and adolescent athlete. During a time of great imbalance between longitudinal growth and muscular development, the physical nature of American football often results in very characteristic fractures to the youth athlete. This chapter will review common pelvic and lower extremity fractures, both of the avulsion and contact type, that befall youth football participants and their subsequent diagnosis, treatment, and potential complications.

BACKGROUND: Press-fit humeral fixation for reverse shoulder arthroplasty (RSA) has been shown to have loosening rates and outcomes similar to a cemented technique; however, increased value has not been reported. The purpose of this study was to determine whether the press-fit technique could improve the value of RSA using the procedure value index (PVI). METHODS: Primary RSA patients with complete hospitalization cost data, preoperative and minimum 2-year postoperative Simple Shoulder Test (SST) scores, and postoperative satisfaction were included. The PVI was calculated as improvement in the SST score (in units of minimal clinically important difference) divided by total cost and normalized. Itemized cost data were obtained from hospital financial records and categorized. Radiographic complications, infections, and revisions were noted. Comparisons were made between the press-fit and cemented RSA cohorts. RESULTS: A total of 176 primary RSA patients (83 cemented and 93 press fit) met the inclusion criteria (mean follow-up period, 44.6 months). Surgical indications (except failed rotator cuff repair), baseline SST scores, and demographic characteristics were similar. The calculated minimal clinically important difference for the SST score was 3.98. The average PVI was significantly greater in the press-fit cohort (1.51 vs 1.03, P

BACKGROUND: The purpose of this study was to introduce the procedure value index (PVI) and apply this value instrument to shoulder arthroplasty. The PVI uses the value equation in units of minimal clinically important difference (MCID) to provide an objective system of quantifying value-driven care. Secondarily, we describe the PVI for both primary anatomic total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA) to highlight value differences between these patient populations. METHODS: Patients undergoing primary shoulder arthroplasty with minimum 2-year follow-up were identified retrospectively. MCIDs were determined for the Simple Shoulder Test (SST) score, American Shoulder and Elbow Surgeons (ASES) score, visual analog scale (VAS) score for pain, and Single Assessment Numeric Evaluation (SANE) score. Cost data were reported as total hospitalization costs, total charges, and total reimbursements. The PVI was calculated as the ratio of outcome improvement in units of MCID over the cost of care. Mean PVIs for TSA and RSA were compared. RESULTS: Five hundred thirty-four patients met the inclusion criteria. MCIDs for the SST, ASES, VAS pain, and SANE scores were 3.61, 29.49, 3.28, and 37.05, respectively. With the exception of the ASES score, improvements in units of MCID were not different between TSA and RSA. However, total hospitalization costs and charges were significantly higher for RSA (P < .001). PVIs based on total hospitalization costs and total charges for the SST, ASES, and VAS pain scores were significantly greater for TSA (P < .05). No other PVI was significantly different. CONCLUSIONS: The PVI was greater for TSA when total hospitalization costs and total charges were considered. The PVI helps highlight value differences in shoulder arthroplasty. LEVEL OF EVIDENCE: Basic Science Study; Development or Validation of Outcome Instrument

Background: In the setting of bilateral shoulder arthroplasty (BSA), differences in functional outcomes and motion between anatomic total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA) are unknown. The purpose of this study was to compare the effectiveness of treatment for various combinations of TSA procedures. Methods: A review of prospectively collected data from an institutional shoulder surgery repository was performed for patients who underwent any combination of bilateral TSA or RSA surgery. Based on the combination of shoulder arthroplasty, patients were divided into the following subgroups: bilateral TSA (TSA/TSA), bilateral RSA (RSA/RSA), or unilateral TSA with contralateral RSA (TSA/RSA). A total of 73 patients (146 shoulders), with a minimum of 2-year follow-up, who underwent any combination of bilateral TSA or RSA from 2007 to 2014 were included. Pre- and postoperative patient-reported outcome measures and measured motion were evaluated between the 3 groups. Results: There were 47 TSA/TSA, 17 RSA/RSA, and 9 TSA/RSA patients with a mean age of 72 years and mean follow-up of 51 months. Preoperatively, TSA/TSA had significantly higher Simple Shoulder Test scores, Visual Analog Scale (VAS) function, active elevation, and active external rotation compared with RSA/RSA. Postoperative scores were significantly superior in TSA/TSA compared with other combinations of shoulder arthroplasty except VAS pain and function. Change in pre- to postoperative (effectiveness of treatment) internal rotation was superior in the TSA/TSA group compared with RSA/RSA and TSA/RSA; however, no other differences were observed. Conclusions: Bilateral TSA patients have higher preoperative function and motion. Although some postoperative outcomes differ among combinations of BSA, the overall effectiveness of treatment for patients undergoing BSA is similar between various combinations of arthroplasty.

Rotator cuff tear (RCT) and cervical spinal stenosis (CSS) are common pathologies in the elderly. Both conditions may present with lateral shoulder pain and weakness or numbness of the upper extremity, potentially affecting patients' ability to live independently. Few data are available on the incidence of CSS among patients with concurrent RCT. The purpose of this study was to investigate the incidence of CSS among RCT patients, demographics, and surgical management using a national insurance database. The Medicare database was used to identify patients with RCT and concomitant CSS by ICD-9 codes from 2005-2014. Trends based on age, gender, and body mass index (BMI) were assessed. Utilization of open and arthroscopic rotator cuff repair (RCR) was compared. A total of 86,501 patients were identified. The number of patients diagnosed with RCT and CSS significantly increased (p0.0001). The incidence of CSS in patients with RCT increased from 9% to 13% (p0.05). Females64 years were more likely to exhibit combined pathology than age-matched males (OR 1.15, 95% CI 1.12 to 1.18) or females65 years (OR 1.64, 96% CI 1.61 to 1.67). A BMI of 30-40 kg/m2 demonstrated the highest incidence (43%, p0.0001). Arthroscopic RCR increased by 2% (p = 0.03) in RCT-CSS. The incidence of CSS in RCT patient is increasing. Orthopedic surgeons should maintain high clinical suspicion for concurrent CSS pathology in patients with RCT, particularly in obese female patients65 years with several medical comorbidities. Further investigation into the influence of these concurrent pathologies on patient outcomes is warranted.

Total knee arthroplasty (TKA) is one of the most commonly performed yet costly surgical procedures in orthopaedics. With national trends and reimbursements moving in favor of shorter hospital length-of-stay (LOS), it is important to understand the complications associated with discharging patients earlier. This is particularly more challenging in a teaching institution due to complexity and variety of layers of care. Therefore, the purpose of this study was to evaluate the 90-day postoperative outcomes among those who were discharged on postoperative day 2 (POD-2) and compare them to a cohort whom had a LOS ≥ 3 days. A retrospective review of all patients who underwent a primary TKA from at a single-teaching institution from 2015 to 2017 was performed. During this time, an accelerated discharge protocol was designed and implanted in our institution. We identified 485 patients who were then substratified into two groups: patients who were discharged on POD-2 (n = 91) with the accelerated protocol and those who were discharged ≥ 3 days (n = 394). Outcomes evaluated included (1) demographics, (2) readmission rates, (3) emergency room (ER) visits, and (4) complication rates within 90 days of TKA. The POD-2 cohort was significantly younger than patients with ≥ 3-day LOS (64 vs. 69 years; p = 0.0001). There were no differences in gender ratios between the 2-day and 3-day cohorts (women, 67 vs. 72%; p = 0.34). Readmission rates (2 vs. 5%; p = 0.31) and ER visits were similar between cohorts (9 vs. 6%; p = 0.4). Medical and surgical complication rates did not differ between the two cohorts, with an overall complication rate of 5.5% in POD-2 versus 5.6% in >3 days LOS (p = 0.97). Patients discharged on POD-2 from TKA did not demonstrate an increased risk of complications, ER visits, or readmissions within 90 days in a teaching institution. However, older patients tended to have a longer LOS.

Nutritional status has become increasingly important in optimizing surgical outcomes and preventing postoperative infection and wound complications. However, currently, there is a paucity in the orthopaedics literature investigating the relationship between nutritional status and wound complications following total knee arthroplasty (TKA). Therefore, the purpose of this study was to determine the prevalence of (1) postoperative infections, (2) wound complications, (3) concomitant infection with wound (CoIW) complication, and (4) infection followed by wound complication by using (1) albumin, (2) prealbumin, and (3) transferrin levels as indicators of nutritional status. These four different outcome measures were chosen as they are encountered commonly in daily clinical practice. A retrospective review of a national private payer database for patients who underwent TKA with postoperative infections and wound complications stratified by preoperative serum albumin (normal: 3.5–5 g/dL), prealbumin (normal: 16–35 mg/dL), and transferrin levels (normal: 200–360 mg/dL) between 2007 and 2015 was conducted. Patients were identified by Current Procedural Terminology (CPT), International Classification of Disease, ninth revision (ICD-9) codes, and Logical Observation Identifiers Names and Codes (LOINC). Linear regression was performed to evaluate changes over times. Yearly rates of infection, as well as a correlation and odds ratio analysis of nutritional laboratory values to postoperative complications, were also performed. Our query returned a total of 161,625 TKAs, of which 11,047 (7%) had postoperative wound complications, 18,403 (11%) had infections, 6,296 (34%) had CoIW, and 4,877 (4%) patients with infection developed wound complications. Albumin was the most commonly ordered laboratory test when assessing complications (96%). Wound complications, infections, CoIW, and infection with wound complications after were higher in those below the normal range: albumin

Substance abuse can have strong negative impacts on surgical outcomes. Therefore, this study assessed the effects of drug abuse in total knee arthroplasty (TKA) patients. Specifically, we identified revision TKA (RTKA): (1) incidence, (2) causes, (3) time to revision, and (4) patient demographics in patients with a history of drug abuse. The Medicare database within the PearlDiver Supercomputer (Warsaw, IN) was queried to identify 2,159,221 TKAs performed between 2005 and 2012. Drug abuse was subdivided into cocaine, cannabis, opioids, sedatives/hypnotics/anxiolytics (SHA), amphetamines, and alcohol abusers. The effect of drug use on the incidence and cause for RTKA, time to revision, as well as patient demographics were correlated using multivariate, analysis of variance, and regression analyses. There was a significant increase in the number of primary TKAs in cocaine (p = 0.011), cannabis (p

INTRODUCTION: This study determines the incidence of opioid use before shoulder arthroplasty and analyzes its influence on postoperative use. METHODS: A retrospective analysis of patients undergoing shoulder arthroplasty with at least 2-year follow-up was performed. Then, at pre- and postoperative appointments, the patients were asked “Do you take narcotic pain medication (codeine or stronger)?” RESULTS: Among 490 patients included in the study, 35.5% reported preoperative opioid use. These patients had higher incidence of opioid use at 1-year follow-up (29.1% versus 4.9%; odds ratio, 8.320; P < 0.001) and at final follow-up (35.1% versus 7.3%; odds ratio, 6.877; P < 0.001). Opioid usage did not change markedly from 1 year follow-up to final follow-up (P > 0.18). DISCUSSION: Approximately one-third of patients used opioids preoperatively and were seven times more likely to continue opioid use postoperatively. Opioid usage did not change from 1 year follow-up to final follow-up, suggesting that patients still using opioids at their 1-year appointment were likely to continue opioid use. LEVEL OF EVIDENCE: Level III

There is a relative paucity of studies that characterized racial disparities in revision total knee arthroplasty (TKA). Therefore, this study was specifically conducted to evaluate the following: (1) incidence; (2) annual burden; (3) causes; and (4) age group distribution of revision TKA among different racial groups in the US sample population. The PearlDiver database was utilized to identify patients with knee osteoarthritis (OA) who underwent primary then subsequent revision TKA from January 2007 to December 2014. Patients were stratified by race, and subset stratification by age was also performed. In each racial cohort, the overall incidence of revision TKA, annual revision burdens, and causes of revisions were calculated and compared. Additionally, a sub-analysis for the incidence of revision TKA stratified by age, in each cohort, was performed. Statistical analysis was performed to demonstrate revision incidence, burden, causes, and age distribution. Revision incidence and burden were the highest in the African-American cohort (12.4%, 11.1%), (p

Recurrent patella instability is a common condition that may potentiate substantial knee dysfunction resulting in loss of time from work and sports. There are numerous factors that contribute to recurrent patella instability including tearing of the medial patellofemoral ligament (MPFL), shallow trochlea, valgus alignment, externally rotated tibia tubercle, ligamentous laxity, elevated Q angle, and increased tibial tuberosity trochlear groove distance. Reconstruction of the MPFL has been shown to restore patella stability where concomitant pathology is within acceptable limits. Major complications include recurrence from inadequate MPFL reconstruction or failure to address other pathology, patella femoral pain from over constrained MPFL or unaddressed cartilage defects to the patella femoral compartment, or patella fracture. This technique provides a reproducible method of restoring patella stability through MPFL reconstruction while minimizing stress risers in the patella by using suture anchor fixation that creates a ligamentous footprint instead of tendon healing into a socket on the patella.

Background Comorbidities have been shown to affect rotator cuff healing and postoperative outcomes. The purpose of this study was to analyze the effect of comorbidities on speed of recovery (SOR) and overall outcomes after arthroscopic rotator cuff repair (RCR). Methods We identified 627 patients who underwent primary arthroscopic RCR from 2006 to 2015. Measured motion and patient-reported outcome measures for pain and function were analyzed for preoperative, 3-month, 6-month, and 1-year intervals. Subgroup analysis of overall outcome and plateau in maximum improvement was performed for diabetes, smoking, obesity, hypercholesterolemia, and age. Results Diabetic patients had worse pain (visual analog scale for pain) and functional outcome (American Shoulder and Elbow Surgeons function, Simple Shoulder Test, visual analog scale for function, and elevation) scores at 6 months and 1 year ( P P Conclusion After arthroscopic RCR, SOR for pain outpaced that for function and motion. Diabetic patients had worse outcomes and earlier plateau points. Earlier plateaus were seen for smokers and for motion in patients with obesity or hypercholesterolemia. Obese patients showed lower functional scores and external rotation. Age did not significantly influence SOR.

The purpose of this study was to delineate the time taken to achieve maximum improvement (plateau of recovery) and the degree of recovery observed at various time points (speed of recovery) for pain and function after arthroscopic rotator cuff repair.An institutional shoulder surgery registry query identified 627 patients who underwent arthroscopic rotator cuff repair between 2006 and 2015. Measured range of motion, patient satisfaction, and patient-reported outcome measures were analyzed for preoperative, 3-month, 6-month, 1-year, and 2-year intervals. Subgroup analysis was performed on the basis of tear size by retraction grade and number of anchors used.As an entire group, the plateau of maximum recovery for pain, function, and motion occurred at 1 year. Satisfaction with surgery was 96% at all time points. At 3 months, 74% of improvement in pain and 45% to 58% of functional improvement were realized. However, only 22% of elevation improvement was achieved (P .001). At 6 months, 89% of improvement in pain, 81% to 88% of functional improvement, and 78% of elevation improvement were achieved (P .001). Larger tears had a slower speed of recovery for Single Assessment Numeric Evaluation scores, forward elevation, and external rotation. Smaller tears had higher motion and functional scores across all time points. Tear size did not influence pain levels.The plateau of maximum recovery after rotator cuff repair occurred at 1 year with high satisfaction rates at all time points. At 3 months, approximately 75% of pain relief and 50% of functional recovery can be expected. Larger tears have a slower speed of recovery.

Hip resection arthroplasty (HRA) is a relatively uncommon, yet viable surgical procedure originally developed by Girdlestone for osteomyelitis of the proximal femur. Currently, HRA is primarily indicated as a salvage procedure after a failed total hip arthroplasty. Despite a continuous rise in the rates of primary and revision hip arthroplasty, there is a lack of published evidence regarding the extent of HRA's current use and its recent trends. We sought to provide an epidemiological description of the recent utilization patterns of HRA in the United States. A level of evidence IV, retrospective case series review of the entire Medicare files between 2005 and 2012 was conducted through the use of current procedural terminology codes and International Classification of Disease ninth edition codes. Linear regressions and chi-square tests were used for analysis. Subgroup analysis was performed by patient age. The total number of HRAs performed between 2005 and 2012 significantly decreased from 4,248 to 3,872 (p = 0.025). There was a significant increase in the annual incidence of HRA among patients younger than 65 years (p = 0.027; 9% increase) and patients 65 to 69 years old (p = 0.007; 22% increase), constituting 43% of the total patients. There was a significant decrease in HRA incidence among patients 80 to 84 years old (p = 0.001; 32% decrease) and patients 85 years old and over (p = 0.002; 24% decrease). Geographic analysis demonstrated the most HRA procedures were performed in the South, whereas gender focused analysis demonstrated a statistically significant decrease in HRA incidence for females (p = 0.003; 6% decrease) and a significant increase in incidence for males (p = 0.003; 7% increase). The overall annual incidence of HRA performed in the Medicare patient population has significantly decreased in recent years. However, this conceals an increased incidence among the relatively younger patient population. Potential causes for these opposing trends include changes in rates of revision surgery, alternative indications for surgery, advances in hardware, and surgeon expertise. This was a level of evidence IV, retrospective case series study.

Recently, with the Medicare bundled payments initiative for total knee arthroplasty (TKA), there has been a move by many institutions to further streamline costs associated with the entire operative and perioperative process. One of these cost-saving strategies has been to favor discharging patients to home with outpatient services as opposed to discharging to the relatively more expensive rehabilitation facilities. Our aim was to determine the success of a teaching institute's initiative in discharging patients to home instead of a rehabilitation facility. Specifically, we evaluated if there were differences in discharge disposition based off of (1) surgeon/patient preference, (2) length of stay, (3) demographics, and (4) postoperative complications. A retrospective review of all patients who had a TKA from 2015 to 2017 at a single teaching institution was performed and assessed discharge to home or to a rehabilitation facility. If they were not discharged to home, we evaluated why that did not happen, stratified the reason they were discharged to a rehabilitation facility into four groups based on (1) physician and occupational health team assessment, (2) patient preference, (3) physician preference, and (4) family or caretaker preference. A total of 229 patients were enrolled in this initiative, with 107 patients (47%) discharged to home with outpatient physical therapy services and 122 (53%) discharged to a rehabilitation facility. Of these, 35 patients (29%) went to these facilities because of physician and occupational health team assessment. However, 31 (25%) patients were due to patient preference, 32 (26%) were because of surgeon's preference, and 24 (20%) were not discharged to home because of family or caretaker preference. There were no differences in length of stay, gender, or complication rates between cohorts. Many patients can be safely discharged to home following TKA at a community teaching institution; however, there continues to be a strong prejudice by patients, physicians, and caretakers to be discharged to a rehabilitation facility despite the home discharge initiative.

Purpose The purpose of this study was to evaluate the outcomes of endoscopic proximal hamstring repair (ePHR), specifically: (1) functional and subjective outcomes, (2) effectiveness of treatment (preoperative-to-postoperative change), (3) complications, (4) acute versus chronic tears, and (5) partial versus complete tears. Methods A retrospective case series of a single-surgeon database for all patients who underwent ePHR between November 2014 and January 2019 with a minimum 1-year follow-up (range, 12 to 48 months) was performed. Charts were analyzed for preoperative and postoperative passive range of motion (PROM), strength, VAS pain, UCLA activity, and modified Harris Hip Score (mHHS). Manual muscle strength testing based on standard grading scale of 0 to 5 was performed. Complications including re-tear of the repair site, infection, iatrogenic nerve injury, inability to return to work/sport at the same level as preinjury, persistent hamstring weakness, pain with sitting, and subsequent surgery were recorded. Results We identified 20 ePHR (6 males, 14 females) with a mean age of 46 years (range, 18 to 63 years). At most recent follow-up, mean VAS pain was 1.85 (SD 2), UCLA activity was 8 (SD 2), mHHS was 90.6 (SD 10.5), and PROM hip flexion of 121.7° (SD 14.5°). Effectiveness of treatment demonstrated significant improvement in objective hamstring strength, hip flexion PROM by 17.3°, UCLA activity by 3, and VAS pain by 3 points. Subjective hamstring weakness was reported in 8 (42.1%) and persistent pain with sitting in 3 (15.8%). Return to work and sport were 100% and 95%, respectively. mHHS was significantly higher postoperatively in patients with complete versus partial tears (95.5 versus 85.7). Conclusion Endoscopic proximal hamstring repair is an effective approach that provides patients significant improvement in pain and function. Level of Evidence IV, Case Series

Background:Advancement in surgical techniques and implants has improved the ability to manage radial head and olecranon fractures. However, trends in management of these fractures are largely unstudied.Objective:This purpose of this study is to evaluate management trends for these common fractures.Methods:A retrospective review of a comprehensive Humana database was performed using Pearl Diver supercomputer (Warsaw, IN, USA) for radial head and neck (RHNF) and olecranon fractures (OF) between 2007 and 2014. Treatment methods including open reduction internal fixation (ORIF), radial head arthroplasty (RHA), and non-operative treatment were reviewed. Total reported incidence of office visits and utilization of each treatment modality were investigated. Sub-analysis with stratification by age 15-74 and greater than 75-years was performed for OF.Results:A total of 10,609 OF and 20,400 RHNF were identified between 2007 and 2014. A significant trend increase in the annual incidence of RHNF (266 cases/year, pincreasein annual percent utilization of RHA (0.22% per year, p=0.011) and a significant trenddecreasein the annual percent utilization of ORIF (-1.0% per year, p=0.004) and non-operative management (-0.53% per year, p=0.046) was observed for RHNF. A significant trendincreasewas observed in percent utilization (0.40% per year, p=0.022) for OF non-operative management, especially in patients over 75 years (66% per year, p=0.034).Conclusion:The percentage of patients being treated with RHA is increasing. Non-operative management of OF has increased, specifically in the patients who are over 75 years.

It is well established that diabetic patients undergoing total knee arthroplasty (TKA) are more susceptible to infection, problematic wound healing, and overall higher complication rates. However, a paucity in current literature exists. The purpose of this study was to determine the effect of hypoglycemia on TKA revision (rTKA) incidence by analyzing a national private payer database for procedures performed between 2007 and 2015 Q1 Q2.A retrospective review of a national private payer database within the PearlDiver Supercomputer application for patients undergoing TKA with blood glucose levels from 20 to 219 mg/mL, in 10-mg/mL increments, was conducted. Patients who underwent TKA were identified by Current Procedural Terminology (CPT) and International Classification of Disease (ICD) codes. Glucose ranges were identified by filtering for Logical Observation Identifiers Names and Codes within the PearlDiver database. Patients with diagnosed diabetes mellitus type I or II were excluded by using ICD-9 codes 250.00-250.03, 250.10-250.13, and 250.20-250.21. rTKA causes including mechanical loosening, failure/break, periprosthetic fracture, osteolysis, infection, pain, arthrofibrosis, instability, and trauma were identified with CPT and ICD-9 codes. Statistical analysis was primarily descriptive.Our query returned 264,824 TKAs, of which 12,852 (4.9%) were revised. Most TKAs were performed with a glucose of 70-99 mg/mL (26.1%), followed by 100-109 mg/mL (18.5%). Patients with TKAs performed with glucose 20-29 mg/mL had the highest rate of revision (17.2%; P.001). Infection was the most common cause of revision among all glucose ranges (P.001).Infection remains one of the most common causes of rTKA irrespective of glucose level. Our results suggest that hypoglycemia may increase revision rates among TKA patients. Tight glycemic control before and during surgery may be warranted.

Utilization of total elbow arthroplasty (TEA) has reportedly increased in recent years. Since the introduction of disease-modifying antirheumatic drugs, there has been a reported decline in its use among rheumatoid patients; yet, the shift in indications for TEA remains unclear. This study evaluated trends in TEA utilization from 2005 to 2012 by analyzing the most common indications within the population of Medicare patients.We performed a retrospective review of a comprehensive Medicare patient population database using the PearlDiver supercomputer (Warsaw, IN, USA) for TEA utilization in rheumatoid arthritis (RA), osteoarthritis (OA), distal humerus fracture (DHF), post-traumatic arthritis (PTA), and distal humerus nonunion (DHNU). Total reported incidence of office visits and TEA utilization for each indication was reviewed.Utilization of TEA remained unchanged (P = .9530) despite a growing Medicare population (P = .0201). There was a significant decline in annual TEA utilization for RA (P = .002) and DHNU (P = .003). No significant change was found in TEA use for DHF, OA, and PTA. A significant increase was noted in total visits coded for OA, RA, and DHNU (P .001). A significant, strong negative correlation was found for office visit coding and TEA use in RA (r = -0.850; P = .008) and DHNU (r = -0.902; P = .002).From 2005 to 2012, utilization rates of TEA in the Medicare population remained constant. Despite increases in office visits, TEA use for RA and DHNU has declined, likely secondary to improved medical management with disease-modifying antirheumatic drugs and the surgeon's comfort with improved fracture fixation options.

Surgical management of proximal humeral fractures has reportedly increased in recent years. Much of this growth relates to a growing elderly population, together with the introduction of modern implants, such as locking plates and, recently, introduction of reverse shoulder arthroplasty (RSA). This study evaluated trends in surgical management of proximal humeral fractures from 2009 to 2012 by analyzing the use of hemiarthroplasty (HA), RSA, and osteosynthesis (open reduction with internal fixation [ORIF]) within the Medicare patient population.We retrospectively reviewed a comprehensive Medicare patient population database within the PearlDiver supercomputer (Warsaw, IN, USA) for proximal humeral fractures treated with HA, RSA, or ORIF. Total use, annual utilization rates, age, and gender were investigated.Within the study period, 32,150 proximal humeral fractures were treated operatively, with no significant change in annual volume (P = .119). The percentage of fractures treated surgically decreased significantly from 16.2% to 13.9% (P .001). The utilization rate decreased significantly for HA from 52% to 39% (P .001), increased significantly for RSA from 11% to 28% (P .001), and did not change significantly for ORIF (P = .164). The utilization rate of RSA nearly tripled for patients older than 65 years (11% to 29%) and doubled for patients younger than 65 (6% to 12%).From 2009 to 2012, utilization rates of ORIF remained fairly constant. HA remains the most commonly used surgical treatment for proximal humeral fractures in the Medicare population, but its use has declined significantly. This decline has been offset by a corresponding increase in RSA.

The purpose of this study was to examine the 90-day costs of three common surgical treatments for proximal humerus fractures and compare the costs associated with the initial day and subsequent 89 days of care. This was conducted through a retrospective review of a national database examining patients who suffered proximal humerus fractures. Patients were stratified by type of surgical procedure performed, hemiarthroplasty (HA), reverse shoulder arthroplasty (RSA), and open reduction and internal fixation (ORIF). RSA was the most costly procedure for the same-day and 90-day costs (p < 0.001). Mean initial day reimbursement costs were significantly different among treatment groups, with the highest costs seen with RSA ($16,151), followed by HA ($9,348), and ORIF ($6,745). Subsequent 89-day reimbursement costs were not significantly different for RSA, HA, and ORIF (p = 0.112). The 90-day costs for the surgical treatment of proximal humerus fractures are driven by the initial day costs. RSA was associated with the highest cost, followed by HA and ORIF.

Worldwide, a great deal of disability is caused by musculoskeletal injuries from high-energy trauma. In nations affected by war, blast injuries associated with mines, missiles, high-powered gunshots, and bombings are one cause of these injuries. Medical missions carried out by those from developed nations is one way to address this. Therefore, it is critical that those who participate in these missions maintain a basic understanding the injuries that may be encountered in nations affected by war and violent conflict. We describe a small number of upper-extremity injuries seen by one orthopedic surgeon during his volunteer medical mission to Jordan. Many of these injuries resulted in the loss of function and/or limb, as these patients were treated without appropriate instrumentation or facilities in a suboptimal environment and in a delayed manner by surgeons who lacked optimal training. It is our hope that this case series will encourage studies that can offer guidance in the ways to treat such complex injuries with optimal safety and efficacy.

Purpose: To evaluate the outcomes of surgical management for external snapping hip in terms of: (1) recurrence; (2) complications; and (3) return to pre-injury activities. Methods: A thorough review of 4 electronic databases- EMBASE, CINAHL Plus, PubMed, and Scopus was performed to find all relevant studies for this review that were published between January 2000 and January 2017 that addressed surgical treatment for external snapping hip. The following reports were excluded: (1) non-English manuscripts; (2) n ⩽ 5; (3) clinical reviews; (4) surgical technique notes; (5) studies only analysing diagnosis; and (6) nonoperative management studies. After cross-referencing, a total of 7 reports were included. Each of these studies was analysed for the incidence of recurrence, revision surgery, complications, and return to pre-injury activity level. Results: There was a recurrence rate of 7% ( n = 8 of 113 hips) with only 1 requiring revision surgery (1%). The cumulative complication rate was 9% ( n = 10 of 113) with all complications being residual weakness. Additionally, we found 98% ( n = 58 of 59) of the patients returned to their pre-injury level of activity. Conclusions: We found operative treatment for external snapping hip to be both safe and efficacious for returning patients to their pre-injury activities. When recurrence does occur, it often is painless and does not require revision surgery. Future studies should be larger and evaluate different surgical techniques to further elucidate the safety and efficacy of surgical treatment for external snapping hip.

Both anatomical total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA) are routinely performed for patients who desire to continuously work or participate in sports. This study analyzes and compares the ability of patients to work and partake in sports following shoulder arthroplasty based on responses to clinical outcome surveys. A retrospective review of the shoulder surgery repository was performed for all patients treated with TSA and RSA and who completed questions 9 and 10 on the activity patient self-evaluation portion of the American Shoulder and Elbow Surgeons (ASES) Assessment Form. Patients with a minimum of 1-year follow-up were included if a sport or work was identified. The analysis included 162 patients with TSA and 114 patients with RSA. Comparisons were made between TSA and RSA in terms of the specific ASES scores (rated 0-3) reported for ability to work and participate in sports and total ASES scores, and scores based on specific sports or line of work reported. Comparisons were also made between sports predominantly using shoulder function and those that do not. TSA patients had a 27% higher ability to participate in sports (average specific ASES score: 2.5 vs 1.9, P < .001) than RSA patients and presented significantly higher scores for swimming and golf. Compared with RSA patients, TSA patients demonstrated more ability to participate in sports requiring shoulder function without difficulty, as 63% reported maximal scores (P = .003). Total shoulder arthroplasty patients also demonstrated a 21% higher ability to work than RSA patients (average specific ASES scores: 2.6 vs 2.1, P < .001), yielding significantly higher scores for housework and gardening. Both TSA and RSA allow for participation in work and sports, with TSA patients reporting better overall ability to participate. For sports involving shoulder function, TSA patients more commonly report maximal ability to participate than RSA patients.

AIM To examine whether opioid dependence or abuse has an effect on opioid utilization after anatomic or reverse total shoulder arthroplasty (TSA). METHODS All anatomic TSA (ICD-9 81.80) and reverse shoulder arthroplasty (RSA) (ICD-9 81.88) procedures from 2007 to 2015 were queried from within the Humana claims database utilizing the PearlDiver supercomputer (Colorado Springs, CO). Study groups were formed based on the presence or absence of a previous history of opioid dependence (ICD-9 304.00 and 304.03) or abuse (ICD-9 305.50 and 305.53). Opioid utilization among the groups was tracked monthly up to 1 year post-operatively utilizing National Drug Codes. A secondary analysis was performed to determine risk factors for pre-operative opioid dependence or abuse. RESULTS Two percent of TSA (157 out of 7838) and 3% of RSA (206 out of 6920) patients had a history of opioid dependence or abuse. For both TSA and RSA, opioid utilization was significantly higher in opioid dependent patients at all post-operative intervals (P < 0.01) although the incidence of opioid use among groups was similar within the first post-operative month. After TSA, opioid dependent patients were over twice as likely to fill opioid prescriptions during the post-operative months 1-12. Following RSA, opioid dependent patients were over 3 times as likely to utilize opioids from months 3-12. Age less than 65 years, history of mood disorder, and history of chronic pain were significant risk factors for pre-operative opioid dependence/abuse in patients who underwent TSA or RSA. CONCLUSION Following shoulder arthroplasty, opioid use between opioid-dependent and non-dependent patients is similar within the first post-operative month but is greater among opioid-dependent patients from months 2-12.

CASE Following the completion of a CrossFit-style challenge (the "Sissy Test"), 2 patients presented with severe pain and swelling over the posterior aspect of the scapula. Magnetic resonance imaging demonstrated isolated edema of the infraspinatus muscle in both patients; the compartments were compressible. Neurovascular checks and observation of range of motion were performed. The patients were treated nonoperatively and were discharged with the diagnosis of overuse syndrome with rhabdomyolysis of the infraspinatus muscle. CONCLUSION With marked increase in the popularity of extreme fitness, monitoring for rhabdomyolysis and potential renal dysfunction is essential.

Anterior cruciate ligament tears are an unfortunate, but common, event in the United States, with an estimated 100-300,000 reconstructions performed annually. Limited literature has been published analyzing the reimbursement patterns for the reconstruction of this ligament and, thus, cost-effectiveness studies have relied mainly on data from a limited number of subjects and hospitals.The purpose of this study was to perform an epidemiological cost analysis of anterior cruciate ligament reconstructions and to analyze and describe the reimbursement patterns for this procedure that can be used as reference for future cost-analysis studies. We conducted a retrospective review of a large private payers insurance company records to identify patients who underwent ACL reconstruction (ACLR) between 2007 and 2014.This was achieved through a structured query of the database with the use of current procedural terminology (CPT) codes. Inclusion criteria for this study were patients housed in the insurer database between the ages of 10 and 59. Reimbursements were calculated at the day of surgery and the 90-day global period. Statistical analysis was based on growth and cohort comparison according to demographic. The consumer price index (CPI) of the Bureau of Labor Statistics was used to calculate inflation.The adjusted mean same-day costs were $11,462 (standard deviations [SD] of $869) for female patients and $12,071 (SD of 561) for males (p=0.07), with no significant difference among same-day costs in either females (p=0.023 for ages 10 to 34 and p=0.037 for ages 35 to 59) or males (p=0.46 for ages 10 to 34 and p=0.26 for ages 35 to 59). The adjusted mean 90-day costs were $14,569 (SD of $835) for females and $14,916 (SD of $780) for males, with no significant difference among 90-day costs in either females (p=0.229 for ages 10 to 34 and p= 0.386 for ages 35 to 39) or males (p=0.425 for ages 10 to 34 and p=0.637 for ages 35 to 39). A matched-age cost analysis demonstrated that gender did not play a significant role in costs (p0.01 for all groups).In the setting of arthroscopic ACLR, both same-day and 90-day costs do not significantly differ between age-matched males and females.

Medial-sided elbow pain is becoming more common among pediatric overhead sport athletes. One potential cause of this is a partial or complete tear of the ulnar collateral ligament (UCL). Because the growth plate remains open in many of these athletes, the most common injury experienced is an avulsion at the medial epicondyle. However, although rare, there is a potential to tear the UCL, with the most common tears occurring at the anterior bundle. However, tears to the posterior bundle are quite rare in pediatric patients. We aim to describe the case of a 10-year old boy who was diagnosed with a partial posterior bundle UCL tear and was successfully treated by cessation of throwing activities and physical therapy. He was able to return to baseball 10 months after his diagnosis.

Background: Total hip arthroplasty (THA) is a common and growing procedure in the United States. Concomitantly, there has been a rise in patients diagnosed with certain types of malignancies including solid organ ones. Unfortunately there is limited data available in the literature that describes the use of THA in patients who concomitantly have one of these forms of cancer. Because of the limited data available in the literature regarding this topic, the purpose of this study was to analyze the trends in use of THA among patients with the five most common malignancies in the United States, which include breast, lung, prostate, colon and bladder cancer according to the National Cancer Institute (NCI). Methods: We conducted a retrospective review of the entire Medicare patient population to analyze the use of THA in patients with a diagnosis of solid organ malignancy including breast, lung, prostate, colon and bladder cancer. Results: Our analysis of over 14 million patients, demonstrate that THA is not as commonly performed procedure in patients with such diagnoses with a 0.26% prevalence. The mean incidence of THA was 0.29%, 0.17%, 0.31%, 0.33% and 0.36% for patients with breast, lung, prostate, colon and bladder cancer respectively. Conclusions: THA in cancer patients are not frequently performed but the use of this technique has increased significantly in patients with lung, prostate and bladder cancer.

An increasing number of total knee arthroplasties (TKAs) are performed on obese patients. It is imperative to remain up to date on the effect of obesity on surgical outcomes and reimbursement trends. The purpose of this study was to evaluate the impact different severities of obesity have on primary and revision TKA, specifically: (1) incidence and trends over time; (2) annual growth rate; and (3) admission costs from 2010 to 2014. A retrospective review of a large commercial private payer database within the PearlDiver Supercomputer application (Warsaw, IN) of TKA procedures was conducted. Patients who underwent TKA and subsequent revision were identified by Current Procedural Terminology (CPT) and ninth revision International Classification of Disease (ICD-9) codes. The index procedure was linked with ICD-9 codes for body mass indexes (BMIs) from 70. Statistical analysis was primarily descriptive to demonstrate the revision incidence and reimbursement deviations due to BMI. Compound annual growth rate (CAGR) was also calculated. Our query returned a total of 87,607 TKA patients within the study BMI ranges. The majority of patients had a BMI of 40 to 44.9 (12.2%) and least in the BMI >70 (0.2%) range. BMI of 40 to 44.9 had the highest overall 5-year mean reimbursement of $11,521 and the highest overall mean 5-year deviation from normal BMI (19–24) patients of $3,300. The incidence and burden of TKA revision was highest in patients with a BMI of 60 to 69.9 (21 and 17.3%, respectively). Average 5-year revision reimbursement and deviation from normal BMI (19–24) was highest in patients with a BMI of 40 to 44.9 ($13,883 and $4,030, respectively). The number of obese patients receiving TKA is steadily rising. The cost of treating obese patients rises as BMI deviates from normal, as does the incidence of revision surgery. Therefore, surgeons must be active in counseling patients on weight optimization as part of preoperative standard of care.

The ability to reach functional capacity following knee arthroplasty depends on the strength of the quadriceps and hamstring muscles. Following total knee arthroplasty, weakness of these muscles can persist for up to one year postoperatively; however, this phenomenon is not well-studied in unicompartmental knee arthroplasty (UKA) patients. Therefore, we assessed: 1) quadriceps muscle strength; 2) hamstring muscle strength; and 3) correlation to functional outcomes.A review of all patients with medial compartment osteoarthritis treated with UKA at a minimum of one-year follow-up was performed. This yielded 26 patients (32 knees), comprising of eight females and 18 males who had a mean age of 67 years (range, 47 to 83 years). Muscle strength was assessed pre-and postoperatively via dynamometer. Functional outcomes were assessed using Knee Society Scores (KSS). Comparisons of groups were performed by paired t-tests.At a minimum one-year postoperatively, quadriceps muscle strength was 27 Nm (range, 13 to 71Nm) and hamstring muscle strength was 19.5Nm (range, 7 to 81Nm). Quadriceps muscle strength increased by 40% (p=0.002) and hamstring muscle strength by 26% (p=0.057). The mean KSS pain was 97 points (range, 85 to 100 points) and mean KSS function was 90 points (range, 45 to 100 points) at the final follow-up. Range of motion was 125° (range, 110° to 135° ) at the final follow-up. The Pearson Correlation Coefficient for postoperative extension strength and postoperative flexion strength to postoperative KSS functional scores were 0.268 and 0.220 respectively.Within one-year following UKA, patients can expect restoration of quadriceps and hamstring muscle strength with a corresponding functional improvement. Although long-term follow-up is warranted to determine sustainability, the short-term results demonstrate excellent restoration of function.

Indications for reverse total shoulder arthroplasty (RTSA) have been expanding, and there has been a recent trend in using RTSA to manage proximal humerus fractures. In this study, we used a large private-payer database to analyze this trend over the period 2010 to 2014 and project RTSA use through 2020. Results showed modest quarterly growth in use of RTSA (4.9% compound quarterly growth rate). The number of RTSAs was projected to more than triple by 2020. RTSA is becoming an increasingly popular treatment option for proximal humerus fractures.

The purpose of this study was to determine if exercise (Ex) protects hearts from arrhythmias induced by glutathione oxidation or ischemia-reperfusion (I/R). Female Sprague-Dawley rats were divided into two experimental groups: sedentary controls (Sed) or short-term Ex (10 days of treadmill running). Twenty-four hours after the last session, hearts were excised and exposed to either perfusion with the thiol oxidant diamide (200 μM) or global I/R. Ex significantly delayed the time to the onset of ventricular arrhythmia after irreversible diamide perfusion. During a shorter diamide perfusion protocol with washout, Ex significantly decreased the incidence of arrhythmia, as evidenced by a delayed time to the first observed arrhythmia, lower arrhythmia scores, and lower incidence of ventricular fibrillation. Ex hearts exposed to I/R (30-min ischemia/30-min reperfusion) also showed lower arrhythmia scores and incidence of ventricular fibrillation compared with Sed counterparts. Our finding that Ex protected intact hearts from thiol oxidation was corroborated in isolated ventricular myocytes. In myocytes from Ex animals, both the increase in H2O2fluorescence and incidence of cell death were delayed after diamide. Although there were no baseline differences in reduced-to-oxidized glutathione ratios (GSH/GSSG) between the Sed and Ex groups, GSH/GSSG was better preserved in Ex groups after diamide perfusion and I/R. Myocardial glutathione reductase activity was significantly enhanced after Ex, and this was preserved in the Ex group after diamide perfusion. Our results show that Ex protects the heart from arrhythmias after two different oxidative stressors and support the hypothesis that sustaining the GSH/GSSG pool stabilizes cardiac electrical function during conditions of oxidative stress.

CASE A 70-year-old woman presented with severe but minimally painful right glenohumeral osteoarthritis (OA), with progressive weakness and numbness radiating to the right hand. Imaging revealed a large fluid collection extending from the joint to the subcoracoid space, with a mass effect on the brachial plexus. A total shoulder arthroplasty (TSA) and decompression of a ganglion cyst were performed. Follow-up with serial electromyography demonstrated resolution of the brachial plexopathy and restoration of function. CONCLUSION Ganglion cysts may arise secondary to severe glenohumeral OA and may compress the surrounding structures, producing a progressive plexopathy. Treatment of the underlying pathology with a TSA may be effective.

Background: Latissimus dorsi transfers have been considered necessary to restore active external rotation following reverse shoulder arthroplasty (RSA). The purpose of this study was to assess the effectiveness of an RSA system that lateralizes the center of rotation in restoring active external rotation without a latissimus dorsi transfer in patients with a preoperative external rotation deficit (external rotation of 0.05 for all). Conclusions: RSA with a lateralized center of rotation can effectively restore external rotation without the use of a latissimus dorsi transfer in patients with a preoperative external rotation deficit as a result of rotator cuff arthropathy or other posttraumatic etiologies. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background Locked anterior shoulder (LAS) with static instability and anterior glenoid bone loss is challenging in the elderly population. Reverse shoulder arthroplasty (RSA) has been employed in treating these patients. No study has compared RSA for LAS with classically indicated RSA. Methods A retrospective case-control study of patients treated with RSA for LAS with glenoid bone loss and static instability was performed using matched controls treated with primary RSA for classic indications. Twenty-four cases and 48 controls were evaluated. Average follow-up was 25.5 months, and median age was 76 years. Motion, outcome assessments, and postoperative radiographs were compared. Results Preoperatively, LAS had significantly less rotation and lower baseline outcome scores. Glenoid bone grafting was more common (P = .05) in the control group (26%) than in the LAS group (6.3%). Larger glenospheres were used more often (P = .001) in the LAS group (75%) than in the control group (29%). Both groups demonstrated significant improvements in pain, function, and outcome scores. Postoperatively, the control group had significantly better elevation and functional outcome scores. With the exception of flexion and Simple Shoulder Test score, effectiveness of treatment was similar between groups. Postoperative acromion stress fractures were seen in 21% of LAS patients and 9% of controls (P = .023) with a predominance of type 3 fractures in LAS. Two LAS patients remained dislocated. Conclusion Patients with LAS treated with RSA can anticipate improvements in pain and function by use of larger glenospheres, often without the need for glenoid bone grafting. Worse postoperative motion and function and a higher incidence of acromion stress fracture may be expected.

Background Radial head arthroplasty (RHA) is a popular method of treatment for complex fractures of the radial head. The purpose of this study was to investigate patient outcomes and radiographic findings associated with a single anatomic monopolar press-fit radial head system commonly used for the treatment of radial head fractures. Methods A retrospective review of prospectively collected data was performed for a consecutive series of patients treated with a press-fit anatomically designed RHA between November 2007 and April 2014. The most recent radiographs were evaluated for loosening, stress shielding, and instability. Postoperative motion and outcomes were reported at most recent follow-up. Results At an average follow-up of 30 months, 6 of the 15 patients (40%) demonstrated radiographic loosening. Six of the 9 patients (67%) without loosening demonstrated stress shielding (average, 6 mm). Functional outcome scores included a mean American Shoulder and Elbow Surgeons score of 70, Mayo Elbow Performance Score of 85, visual analog scale score for pain of 2, visual analog scale score for function of 7, and Single Assessment Numeric Evaluation score of 75. Average flexion-extension arc was 14° to 138°, and average pronation-supination was 75° to 74°. All 6 of the patients with radiographic loosening had undergone RHA with an associated ligamentous injury repair. Satisfaction among patients was high as no patient reported an unsatisfactory outcome. Conclusions The use of an anatomic, press-fit monopolar RHA in the management of acute complex radial head fractures has yielded excellent clinical outcomes despite high rates of radiographic loosening and stress shielding. Press-fit RHA in the setting of ligamentous injury warrants further investigation because of a high rate of implant loosening observed.

Background: The ability to reach full functional capacity following total knee arthroplasty (TKA) is reliant on the strength of the quadriceps and hamstring muscles. Weakness of these muscles can persist anywhere from one to three years post-operatively. There remains considerable controversy as to what factors influence restoration of muscle strength after TKA. Implant designs have been implicated in the ability of patients to recover. Currently there is a paucity of literature available describing the influence of patient characteristics, surgical factors, and clinical outcomes on quadriceps and hamstring muscle strength following TKA with a cruciate-retaining, single radius (SR) implant. For this reason, we sought to investigate TKA patients for: (I) quadriceps muscle strength; (II) hamstring muscle strength; (III) flexion/extension (F/E) ratio; (IV) clinical outcome scores; (V) influence of patient characteristics on muscle strength at one-year post-operatively. Methods: A review of TKA patients who were assessed for hamstring and quadriceps muscle strength was conducted. A total of 39 patients (26 men and 13 women), who had a mean age of 68 years (range, 51 to 88 years) were included. Isokinetic dynamometer testing at 180 degree/second for 3 sets of 10 repetitions in extension and flexion were performed by an independent physical therapist to assess dynamic concentric torque of the hamstrings and quadriceps muscle. F/E ratios were calculated. TKA was performed via subvastus (n=20) or midvastus (n=19) approach. Subgroup analysis for surgical approach, concomitant spinal pathology (n=11), gender, age and body mass index (BMI) were performed. Knee Society Scores (KSS) and range of motion (ROM) were assessed at each visit. Comparisons of groups were performed using paired t-tests. Results: Mean postoperative relative extension torque was 23 Nm/kg (range, 9 to 43 Nm/kg), representing a mean increase of 38% (range, −16% to 100%; P=0.0267) from pre-operative status. A mean increase of 27% (range, −15% to 100%; P=0.0433) in flexion strength and mean relative flexion torque of 19 Nm/kg (range, 8–37 Nm/kg) was observed. Pre-operative mean F/E ratio was 0.8 and 0.9 post-operatively (P=0.3028). Men demonstrated significantly greater improvements in flexion compared to women (22% vs. 12%; P vs. 15%; P=0.0537). Postoperative F/E was similar for males (0.8) and females (0.9; P=0.4454). Surgical approach did not influence quadriceps muscle strength (P=0.1786) or hamstrings muscle strength (P=0.9592). History of spine pathology had no impact on muscles strength (hamstring, P=0.5684; quadriceps, P=0.7221). For the overall group, a mean KSS pain score was 96 points (range, 84 to 100 points), KSS function was 96 points (range, 96–100 points), and mean ROM of 0 to 114 degrees. Conclusions: Restoration of quadriceps and hamstring muscle strength can be expected at 1 year post-operatively regardless of gender, surgical approach or concomitant spinal pathology. Further comparative investigation on the impact of implant design on hamstring and quadriceps muscle strength is warranted. However, the use of a SR, CR TKA system demonstrated significant improvements post-operatively in quadriceps and hamstring strength.