Quality of prospective controlled randomized trials regarding platelet-rich plasma injection for osteoarthritis of the knee.

BACKGROUND: Randomized controlled trials (RCTs) are the gold standard for study design and are considered to have the highest level of evidence. The purpose of this study is to evaluate quality of evidence of prospective RCTs that investigated the clinical efficacy of platelet-rich plasma (PRP) treatments for knee osteoarthritis. We hypothesized that a high level of clinical evidence does not correlate with a high-quality scientific study. MATERIAL AND METHODS: A systematic literature search to identified RCTs that evaluated the efficacy of PRP treatments for knee osteoarthritis. Inclusion criteria included studies that contained key terms "Platelet-rich plasma," "PRP", "knee", and "osteoarthritis". Exclusion criteria excluded studies that were not prospective RCTs. Ten RCTs were evaluated by four independent reviewers. The studies were assessed according to the Oxford Levels of Evidence, a modified Coleman Methodology Score, and the revised Consolidated Standards of Reporting Trials (CONSORT) score. RESULTS: Three of the four Observers rated all 10 studies as Level I, while one Observer rated 80% of the studies as Level I. Using the Coleman Methodology Score, the average score for all studies was 58.0 out of 100 points, designating the studies as "fair." Areas of deficiency included clinical effect measurement and intent-to-treat analysis. Using the CONSORT checklist, the average score was 16.9 out of 22 points, designating the studies as "good". Areas of deficiency included inadequate implementation of randomization and interpretation of results. DISCUSSION: Clinicians should critically evaluate research studies regardless of study design. A sophisticated study design and high level of evidence designation does not guarantee quality research. We determined that RCTs for PRP treatment of knee osteoarthritis were not as robust in quality despite their Level I Oxford Level of Evidence rating.

Early Stabilization of Femur Fractures in the Setting of Polytrauma Is Associated With Decreased Risk of Pulmonary Complications and Mortality.

Timing of definitive fixation of femoral shaft fractures is a subject of continued controversy. The purpose of this study was to determine if early definitive fixation of femoral shaft fractures in the setting of polytrauma decreased the risk of pulmonary complications and mortality. The 2009-2012 National Sample Program of the National Trauma Data Bank was queried for all patients 18 to 65 years with Injury Severity Scores (ISS) >15 who underwent definitive fixation of femoral shaft fractures. Mortality, perioperative complications, and length of intensive care unit (ICU) and hospital stay were the primary outcome measures of interest. Following multivariate analyses, increased time to surgery was found to portend a statistically significant increased risk of acute respiratory distress syndrome(ARDS), mean ventilator time, length of ICU and hospital stay, and mortality. Earlier definitive fixation of femoral shaft fractures in the setting of polytrauma is associated with significantly decreased risk of ARDS, mean ventilator time, length of ICU and hospital stay, and mortality. (Journal of Surgical Orthopaedic Advances 28(2):137-143, 2019).

Vascular Injuries in Combat-Specific Soldiers during Operation Iraqi Freedom and Operation Enduring Freedom.

BACKGROUND: This study sought to identify vascular injury patterns among combat-specific cavalry scout personnel within the Iraq and Afghanistan Wars. METHODS: The Armed Forces Medical Examiner System and Joint Theater Trauma Registry were queried for all injuries with the cavalry scout designation from 2003 to 2011, including those both wounded in action (WIA) and killed in action (KIA). A description of vascular injury, combat causality care statistics, mechanism of injury, and demographic data were recorded. RESULTS: Sixteen percent (n = 111) of the 701 cavalry scouts with a combat wound sustained a vascular injury. Among cavalry scouts sustaining vascular injuries, 69% were caused by an explosive mechanism of injury, 63% were KIA, and 29% had a major extremity amputation. Cavalry scout soldiers with a vascular injury were significantly more likely to result from explosion (P < 0.0001), be KIA (P < 0.0001), and occur in Iraq (P < 0.0001). The rate of noncompressible arterial injury was 65%. WIA cavalry scout soldiers with a compressible vascular injury with clear documentation of prehospital tourniquet utilization arrived at a Medical Treatment Facility in 67% of cases with a tourniquet in place. Of these transported with a prehospital tourniquet 83% survived. CONCLUSIONS: The high rates of KIA and extremity amputation among cavalry scout soldiers with a vascular injury denotes the lethality of these combat injuries. Uniformly equipping soldiers with battlefield tourniquets and educating them on their prehospital use might improve the survivorship of those servicemembers sustaining a compressible vascular injury.

Tibial Tubercle Osteotomy for Patellar Chondral Pathology in an Active United States Military Population.

PURPOSE: To quantify rates of perioperative complications, secondary surgery, subjective pain relief, and knee-related medical separation in an active military population after a tibial tubercle osteotomy (TTO) for the primary indication of chondral pathology. METHODS: All active-duty service members undergoing TTO with a minimum of 2 years' follow-up were isolated from the Military Health System database. The exclusion criteria were patients with patellar instability, other periarticular osteotomy, and insufficient follow-up. Demographic information and surgical characteristics were abstracted from the electronic health record and correlated with improvement in pain and medical discharge from the military. RESULTS: A total of 76 patients (86 knees) who underwent TTO for patellofemoral chondromalacia were identified with a mean age of 32.3 years. Major and minor complications occurred in four patients (4.7%) and three patients (3.5%), respectively, and the overall improvement in the visual analog scale score after TTO was 1.5 (P < .0001). At a mean follow-up of 3.4 years (range, 2.0 to 7.3 years), 37% of patients were unable to return to modified military activity because of knee-related limitations. Junior military rank group (P = .0084), age younger than 35 years (P = .0031), bilateral TTO procedures (P = .0294), and tobacco use (P = .0218; odds ratio, 3.29; 95% confidence interval, 1.19 to 9.12) were risk factors for medical separation, whereas absence of concomitant chondral repair (P = .5408), previous knee procedures (P = .9674), and greater occupational demands (P = .7062) were not. CONCLUSIONS: At short-term to midterm follow-up, 63% of patients successfully returned to military function with a low rate of perioperative complications (8%). The postoperative decrease in pain after TTO is of unknown clinical significance. Age younger than 35 years, junior military rank, bilateral TTO procedures, and tobacco use were significant risk factors for medical separation, whereas absence of concomitant cartilage repair, previous knee procedures, and lower occupational demands were not associated with improved visual analog scale scores or prevention of knee-related medical discharge. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Predictors of hospital readmission following revision total knee arthroplasty.

PURPOSE: Hospital readmission is emerging as an important quality measure, yet modifiable predictors of readmission remain unknown. This study was designed to identify risk factors for readmission following revision total knee arthroplasty. METHODS: The National Surgical Quality Improvement Program dataset was queried to identify patients undergoing revision total knee arthroplasty from 2011 to 2012. Patient demographics, medical co-morbidities, laboratory values, surgical characteristics and surgical outcomes were examined using bivariate and multivariate logistic regression to identify significant predictors for readmission within 30 days of discharge. RESULTS: There were 108 readmissions (6.2 %) among 1754 patients. Risk factors for readmission included a history of transient ischaemic attack/cerebrovascular accident (OR 3.47; 13 95 % CI 1.30, 9.25), female sex (OR 1.75, 95 % CI 1.15, 2.68) and general anaesthesia (OR 14 1.74, 95 % CI 1.09, 2.79). Hypertension treated with medication (OR 0.61, 95 % CI 0.39, 0.96) was associated with a lower risk of readmission. Post-operative complications that were significant predictors of hospital readmission included periprosthetic joint infection (OR 15.09, 95 % CI 5.57, 40.91), superficial wound infection (OR 16.57, 95 % CI 5.82, 47.22) and deep venous thrombosis (OR 8.59, 95 % CI 2.36, 31.24). CONCLUSIONS: The preferred use of neuraxial anaesthesia and coordinated discharge planning in patients with a history of transient ischaemic attack/cerebrovascular accident may reduce the risk of readmission following discharge after revision total knee arthroplasty. Additionally, patients with post-operative infections and deep venous thrombosis following these procedures can benefit from close observation in the first weeks following discharge to minimize the likelihood of readmission. LEVEL OF EVIDENCE: III.

The Total Joint Arthroplasty Cardiac Risk Index for Predicting Perioperative Myocardial Infarction and Cardiac Arrest After Primary Total Knee and Hip Arthroplasty.

BACKGROUND: Current indices fail to consistently predict risk for major adverse cardiac events after major total joint arthroplasty. METHODS: All primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) were identified from the National Surgical Quality Improvement Program data set. Based on prior analyses, age ≥80 years, history of hypertension, and history of cardiac disease were evaluated as predictors of myocardial infarction and cardiac arrest using stepwise multivariate logistic regression. A series of predictive scores were constructed and weighted to identify the influence of each variable on 30-day postoperative cardiac events, while comparing with the Revised Cardiac Risk Index (RCRI). RESULTS: Among 85,129 patients, age ≥80 years, hypertension, and a history of cardiac disease were all statistically significant predictors of postoperative cardiac events (0.32%; n = 275) after TKA and THA (P ≤ .02). Equal weighting of all variables maintained the highest discriminative capacity in both THA and TKA cohorts. Adjusted models explained 75% and 71% of the variation in postoperative cardiac events for those with THA and TKA, respectively, without statistically significant lack of fit (P = .52; P = .23, respectively). Conversely, the RCRI was not a significant predictor of postoperative cardiac events after TKA (odds ratio, 3.36; 95% CI, 0.19, 58.04; P = .40), although it maintained a similar discriminative capacity after THA (76%). CONCLUSION: The current total joint arthroplasty Cardiac Risk Index score was the most economical in predicting postoperative cardiac complication after primary unilateral TKA and THA. The RCRI was not a significant predictor of perioperative cardiac events for TKA patients but performed similarly to the current model for THA.

The Rising Incidence of Degenerative and Posttraumatic Osteoarthritis of the Knee in the United States Military.

BACKGROUND: This investigation sought to quantify incidence rates (IRs) and risk factors for primary and secondary (ie, posttraumatic) osteoarthritis (OA) of the knee in an active military population. METHODS: We performed a retrospective review of United States military active duty servicemembers with first-time diagnosis of primary (International Classification of Disease, 9th Edition code: 715.16) and secondary (International Classification of Disease, 9th Edition code: 715.26) OA of the knee between 2005 and 2014 using the Defense Medical Epidemiology Database. IRs and 95% CIs were expressed per 1000 person-years, with stratified subgroup analysis adjusted for sex, age, race, military rank, and branch of military service. Relative risk factors were evaluated using IR ratios and multiple regression analysis. RESULTS: A total of 21,318 cases of OA of the knee were identified among an at-risk population of 13,820,906 person-years for an overall IR of 1.54 per 1000 person-years, including 19,504 cases of primary (IR: 1.41) and 1814 cases of secondary OA (IR: 0.13). The IRs of both primary and secondary OA increased significantly from 2005 to 2014. Increasing age (P < .0001); black race (P < .001); senior military rank (P < .0001); and Army, Marines, and Air Force services (P < .0001) were significantly associated with an increased risk for knee OA. CONCLUSION: This study is the first large-scale report of knee OA in a young athletic population. An increasing incidence and several risk factors for knee OA were identified, indicating a need for better preventative strategies and forecasting the increased anticipated demands for knee arthroplasty among US military servicemembers.

Long versus short cephalomedullary nail for trochanteric femur fractures (OTA 31-A1, A2 and A3): a systematic review.

BACKGROUND: Both long and short cephalomedullary nails (CMN) may be used to treat trochanteric femur fractures. The objective of this paper was to compare the clinical outcomes between long and short CMN in the treatment of trochanteric hip fractures. MATERIALS AND METHODS: A literature search was performed, identifying 135 papers; 4 of which met inclusion and exclusion criteria. Papers included were those that compared cohorts of long and short nails for stable trochanteric femur fractures of level III evidence or superior. Data was pooled and analyzed, focusing on reoperation rate, secondary femoral shaft fracture rate, estimated blood loss, transfusion rate, operative time and length of stay. RESULTS: Included in the analysis were 1276 patients, with 438 short and 838 long CMN. The average age was 82.0 years for short CMN and 79.0 years for long CMN (P = 0.0002). The average follow up was 18 months, 46 % were male, and 71 % had an ASA (American Society of Anesthesiologists score) classification ≥3. The rate of reoperation was 5.0 % and 3.8 % for short and long CMN, respectively (P = 0.31). The rate of refracture was 1.6 % and 0.95 % for short and long CMN, respectively (P = 0.41). As compared to long nails, short nails had an average blood loss of 39 mL less (P = 0.0003), an 8.8 % decrease in transfusion rate (P = 0.07), and incurred 19 min less operative time (P < 0.0001). No significant differences between short and long nails were observed for either other complications, hardware complications, non-union, or mortality. CONCLUSIONS: For trochanteric femur fractures, short CMN have a low reoperation rate while significantly decreasing operative time and estimated blood loss with the additional benefit of being cost effective. LEVEL OF EVIDENCE: Level 3.

Predictors of length of stay after elective total shoulder arthroplasty in the United States.

BACKGROUND: Total shoulder arthroplasty (TSA) is an increasingly used treatment of glenohumeral arthritis and proximal humerus fractures. However, patient-specific characteristics affecting length of hospital stay postoperatively have not been elucidated. METHODS: All patients undergoing primary unilateral TSA between 2005 and 2011 were isolated from the National Surgical Quality Improvement Program database. Patient demographics, medical comorbidities, and selected surgical variables were extracted, and length of stay was established as the primary end point of interest. Risk factors were expressed as odds ratios (ORs) with 95% confidence intervals by bivariate and multivariable analysis. RESULTS: A total of 2004 patients were identified; the average age was 68.8 years, and 57% were women. Mean length of stay after TSA was 2.2 days (standard deviation, 1.7), and 91% of cases received hospital discharge in <3 days. Multivariable logistic regression analysis identified renal insufficiency (OR, 11.35; P = .0002), increased age (OR, 2.13; P = .011), longer operative time (OR, 1.94; P = .0041), and American Society of Anesthesiologists class ≥3 (OR, 1.86; P = .0016) as the most significant risk factors for length of stay. Gender also influenced length of stay; women were more likely to stay ≥4 days (OR, 0.44; P < .0001). CONCLUSIONS: Perioperative risk stratification and preoperative counseling are paramount for patients undergoing TSA, particularly for those individuals with cardiac and renal disease or of advancing age. These variables may effectively predict prolonged hospital stay after TSA.

Thirty-day morbidity and mortality after elective total shoulder arthroplasty: patient-based and surgical risk factors.

BACKGROUND: Total shoulder arthroplasty (TSA) is an effective treatment for painful glenohumeral arthritis, but its morbidity has not been thoroughly documented. METHODS: The National Surgical Quality Improvement Program database was queried to identify all patients undergoing primary TSA between 2006 and 2011, with extraction of selected patient-based or surgical variables and 30-day clinical course. Postoperative complications were stratified as major systemic, minor systemic, major local, and minor local, and mortality was recorded. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were derived from bivariate and multivariable analysis to express the association between risk factors and clinical outcomes. RESULTS: Among the 2004 patients identified, the average age was 69 years, and 57% were women. Obesity was present in 46%, and 48% had an American Society of Anesthesiologists classification of ≥3. The 30-day mortality and total complication rates were 0.25% and 3.64%, respectively. Comorbid cardiac disease (OR, 85.31; 95% CI, 8.15, 892.84) and increasing chronologic age (OR, 1.19; 95% CI, 1.06, 1.33) were independent predictors of mortality, whereas peripheral vascular disease was associated with statistically significant increase in any complication (OR, 6.25; 95% CI, 1.24, 31.40). Operative time >174 minutes was an independent predictor for development of a major local complication (OR, 4.05; 95% CI, 1.45, 11.30). Obesity was not associated with any specified complication after controlling for other variables. CONCLUSIONS: Whereas TSA has low short-term rates of perioperative complications and mortality, careful perioperative medical optimization and efficient surgical technique should be emphasized to decrease morbidity and mortality.

Return to Work and Functional Outcomes Following Primary Total Knee Arthroplasty in U.S. Military Servicemembers.

UNLABELLED: This investigation sought to determine occupational outcomes after total knee arthroplasty (TKA) in a high-demand cohort. A total of 159 military servicemembers underwent 181 primary TKAs with mean follow-up of 4.1 (range, 2.0-6.6) years. Approximately 18% of servicemembers underwent medical separation from the military due to TKA-related limitations, and age <45 years (OR=2.36; 95% CI: 1.14, 4.90) was established as the significant risk factor. Twenty servicemembers (12.6%) performed postoperative combat deployments, with age <45 years (OR=3.10; 95% CI: 1.29, 7.47) or combat arms designation (OR=2.75; 95% CI: 1.13, 6.73) associated with higher rates of deployment. Nine revision TKAs (5.0%) were performed at an average of 1.9 years. Following TKA, 82% of servicemembers remained on active-duty or completed their military service. LEVEL OF EVIDENCE: IV.

Army orthopaedic surgery residency program directors' selection criteria.

Factors associated with successful selection in U.S. Army orthopaedic surgical programs are unreported. The current analysis includes survey data from all Army orthopaedic surgery residency program directors (PDs) to determine these factors. PDs at all Army orthopaedic surgery residency programs were provided 17 factors historically considered critical to successful selection and asked to rank order the factors as well as assign a level of importance to each. Results were collated and overall mean rankings are provided. PDs unanimously expressed that performance during the on-site orthopaedic surgery rotation at the individual program director's institution was most important. Respondents overwhelmingly reported that Steps 1 and 2 licensing exam scores were next most important, respectively. Survey data demonstrated that little importance was placed on letters of recommendation and personal statements. PDs made no discriminations based on allopathic or osteopathic degrees. The most important factors for Army orthopaedic surgery residency selection were clerkship performance at the individual PD's institution and licensing examination score performance. Army PDs consider both USMLE and COMLEX results, because Army programs have a higher percentage of successful osteopathic applicants.

Morbidity and mortality in the thirty-day period following total hip arthroplasty: risk factors and incidence.

The study sought to ascertain the incidence rates and risk factors for 30-day post-operative complications after primary total hip arthroplasty (THA). Complications were categorized as systemic or local and subcategorized as major or minor. There were 17,640 individuals who received primary THA identified from the 2006-2011 ACS NSQIP. The mortality rate was 0.35% and complications occurred in 4.9%. Age groups ≥ 80 years (P <0.001) and 70-79 years old (P = 0.003), and renal insufficiency (P = 0.02) best predicted mortality. Age ≥80 years (P <0.001) and cardiac disease (P = 0.01) were the strongest predictors of developing any postoperative complication. Morbid obesity (P <0.001) and operative time > 141 minutes (P <0.001) were strongly associated with the development of major local complications.

Risk factors for complications and in-hospital mortality following hip fractures: a study using the National Trauma Data Bank.

STUDY DESIGN: Retrospective review of prospectively collected data. OBJECTIVE: To describe the impact of patient demographics, injury-specific factors, and medical co-morbidities on outcomes after hip fracture using the National Sample Program (NSP) of the National Trauma Data Bank (NTDB). METHODS: The 2008 NSP-NTDB was queried to identify patients sustaining hip fractures. Patient demographics, co-morbidities, injury-specific factors, and outcomes (including mortality and complications) were recorded and a national estimate model was developed. Unadjusted differences for risk factors were evaluated using t test/Wald Chi square analyses. Weighted logistic regression and sensitivity analyses were performed to control for all factors in the model. RESULTS: The weighted sample contained 44,419 incidents of hip fracture. The average age was 72.7. Sixty-two percent of the population was female and 80 % was white. The mortality rate was 4.5 % and 12.5 % sustained at least one complication. Seventeen percent of patients who sustained at least one complication died. Dialysis, presenting in shock, cardiac disease, male sex, and ISS were significant predictors of mortality, while dialysis, obesity, cardiac disease, diabetes, and a procedure delay of ≥2 days influenced complications. The major potential modifiable risk factor appears to be time to procedure, which had a significant impact on complications. CONCLUSIONS: This is the first study to postulate predictors of morbidity and mortality following hip fracture in a US national model. While many co-morbidities appear to be influential in predicting outcome, some of the more significant factors include the presence of shock, dialysis, obesity, and time to surgery. LEVEL OF EVIDENCE: Prognostic study, Level II.

The combat burst fracture study--results of a cohort analysis of the most prevalent combat specific mechanism of major thoracolumbar spinal injury.

INTRODUCTION: In 2009-2010, military physicians hypothesized that a new pattern of spinal injury had emerged, resulting from improvised explosive device assault on up-armored vehicles, associated with a high rate of point of first contact fracture and neurological injury-the combat burst fracture. We sought to determine the incidence of all thoracolumbar (TL) burst fractures and combat burst fractures in 2009-2010 as compared to two antecedent years. METHODS: A screening process identified all individuals who sustained TL burst fractures in the time-period studied. Demographics, injury-specific characteristics, mechanism of injury, surgical interventions and early complications were recorded. Incidence rates were calculated for the three time periods using total deployed troop-strength and number of LRMC combat admissions as denominators. The incidences of TL burst fractures within each year group and by mechanism were compared, and clinical characteristics and process of care were described. RESULTS: Between 2007-2010, 65 individuals sustained a TL burst fracture. The incidence of these injuries in 2009-2010 was 2.1 per 10,000 soldier-years and accounted for 3.0 % of LRMC combat-casualty admissions, a significant increase from 0.6 % and 1.1 % in 2007-2008 and 2008-2009, respectively (p ≤ 0.001). In 2009-2010, US soldiers were 3.4-4.6 times more likely to sustain a TL burst fracture compared to 2008-2009 and 2007-2008 (p < 0.001), and the most common mechanism of injury was IED vs. vehicle (65 %)-the combat burst fracture mechanism. Neurological deficits were present in 43 % of TL burst fractures and 1/3 were complete injuries. Spinal fixation was performed in 68 % overall and 74 % of combat burst fractures. CONCLUSIONS: There was a 3.4- to 4.6-fold increase in TL burst fractures in 2009-2010 compared to antecedent years. The primary driver of this phenomenon was the marked increased in combat burst fractures. Mitigating/preventing the mechanism behind this major spinal injury is a key research initiative for the US military. Level of Evidence III (Case-control).

Occupational and Functional Outcomes following Patellofemoral Arthroplasty in U.S. Military Servicemembers.

The functional outcomes in patients undergoing patellofemoral arthroplasty (PFA) with high occupational demands have not been fully examined. This study assessed return to work and conversion to TKA rates following PFA in a young, military cohort. Patient demographics, pain scores, and surgical information were retrospectively collected for all active-duty military members who underwent PFA over a 4-year period. The data were then analyzed to calculate return to work, conversion to TKA, and perioperative complications rates. A total of 48 servicemembers with 60 total PFAs (36 unilateral, 12 bilateral) were included, with a mean follow up of 2.2 years. At the final follow-up, 83% of servicemembers returned to military service or completed their service obligation after PFA. Conversion to TKA occurred in three (6.2%) patients at an average of 2.4 years after PFA, resulting in a PFA annual revision rate of 2.3%. The mean numeric rating scale for pain improved from 4.9 ± 2.6 at baseline to 2.5 ± 2.0 postoperatively (p < 0.001). Servicemembers with at least one prior ipsilateral knee procedure had a significantly decreased odds ratio (OR) for both occupational outcome failure (OR, 0.03; 95% confidence interval [CI], 0-0.29) and overall failure (OR, 0.13; 95% CI, 0.02-0.78). At an average of 2 years following PFA, 83% of military members returned to duty, with a low rate of revision to TKA. Prior ipsilateral knee procedure decreased the probability of medical separation. LEVEL OF EVIDENCE: IV.

The impact of resident involvement on post-operative morbidity and mortality following orthopaedic procedures: a study of 43,343 cases.

BACKGROUND: Few studies have addressed the role of residents' participation in morbidity and mortality after orthopaedic surgery. The present study utilized the 2005-2010 National Surgical Quality Improvement Program (NSQIP) dataset to assess the risk of 30-day post-operative complications and mortality associated with resident participation in orthopaedic procedures. METHODS: The NSQIP dataset was queried using codes for 12 common orthopaedic procedures. Patients identified as having received one of the procedures had their records abstracted to obtain demographic data, medical history, operative time, and resident involvement in their surgical care. Thirty-day post-operative outcomes, including complications and mortality, were assessed for all patients. A step-wise multivariate logistic regression model was constructed to evaluate the impact of resident participation on mortality- and complication-risk while controlling for other factors in the model. Primary analyses were performed comparing cases where the attending surgeon operated alone to all other case designations, while a subsequent sensitivity analysis limited inclusion to cases where resident participation was reported by post-graduate year. RESULTS: In the NSQIP dataset, 43,343 patients had received one of the 12 orthopaedic procedures queried. Thirty-five percent of cases were performed with resident participation. The mortality rate, overall, was 2.5 and 10 % sustained one or more complications. Multivariate analysis demonstrated a significant association between resident participation and the risk of one or more complications [OR 1.3 (95 % CI 1.1, 1.4); p < 0.001] as well as major systemic complications [OR 1.6 (95 % CI 1.3, 2.0); p < 0.001] for primary joint arthroplasty procedures only. These findings persisted even after sensitivity testing. CONCLUSIONS: A mild to moderate risk for complications was noted following resident involvement in joint arthroplasty procedures. No significant risk of post-operative morbidity or mortality was appreciated for the other orthopaedic procedures studied. LEVEL OF EVIDENCE: II (Prognostic).

Functional outcomes of hip arthroplasty in active duty military service members.

There are few reports on outcomes after hip arthroplasty in the military population despite increases among young, active patients. U.S. Army service members with coded hip arthroplasty between 2004 and 2010 were reviewed. Patient demographic variables were correlated with occupational outcomes. Of 183 patients, the occupational outcomes at a minimum 2 years postoperatively for service members undergoing primary hip arthroplasty were medically separated (n = 44, 24%), retired (n = 82, 45%), and returned to active duty (n = 57, 31%). Multivariate analysis identified that age less than 40 years [odds ratio (OR), 3.41; 95% confidence interval (CI), 1.14, 10.12] and enlisted rank (OR, 3.63; 95% CI, 1.29, 10.20) as major independent risk factors for medical separation. Univariate analysis revealed that officer rank had an increased likelihood of postoperative combat deployment than enlisted rank (OR, 3.39; 95% CI, 1.50, 7.94). Despite encouraging results in the civilian literature, this study documents modest retention rates on active duty at a minimum of 2 years after primary hip arthroplasty.

Patellar dislocation in the United States: role of sex, age, race, and athletic participation.

Patellar instability has been extensively studied in selected, high-risk cohorts, but the epidemiology in the general population remains unclear. A longitudinal, prospective epidemiological database was used to determine the incidence and demographic risk factors for patellar dislocations presenting to emergency departments of the United States. The National Electronic Injury Surveillance System was queried for all patellar dislocations presenting to emergency departments between 2003 and 2008. Incidence rate ratios (IRRs) were then calculated with respect to sex, age, and race. The hypothesis was that patellar dislocation is influenced by sex, age, race, and athletic participation. An estimated 40,544 patellar dislocations occurred among an at-risk population of 1,774,210,081 person-years for an incidence rate of 2.29 per 100,000 person-years in the United States. When compared with males, females showed no significant overall or age-stratified differences in the rates of patellar dislocation (IRR 0.85, 95% CI 0.71, 1.00; p = 0.08; p > 0.05). Peak incidence of patellar dislocation occurred between 15 and 19 years of age (11.19/100,000 person-years). When compared with Hispanic race, black and white race were associated with significantly higher rates of patellar dislocation (IRR 4.30 [95% CI 1.63, 6.97; p = 0.02], IRR 4.02 [95% CI 1.06, 6.98; p = 0.03], respectively). Nearly half (51.9%) of all patellar dislocation occurred during athletic activity, with basketball (18.2%), soccer (6.9%), and football (6.3%) associated with the highest percentage of patellar dislocation during athletics. Age between 15 and 19 years is associated with higher rates of patellar dislocation. Sex is not a significant risk factor for patellar dislocation. Black and white race are a significant risk factor for patellar dislocation when compared with Hispanic race. Half of all patellar dislocation occurs during athletic activity. This study was conducted on the Level of evidence II.

Publication rate of presentations at an annual military orthopaedic meeting.

Many research abstracts presented at orthopaedic conferences do not undergo a formal editorial, or peer-review process; however, abstracts are frequently referenced in textbooks and influence clinical practice. The purpose of this study was to determine the publication rate of abstracts formally presented at the Society of Military Orthopaedic Surgeons (SOMOS) annual meetings from 1998 to 2006 that went to full-text publication. Using Google Scholar and PubMed, a literature search was performed for each abstract presented at the annual SOMOS meeting in the years 1998-2006, to calculate the overall full-text publication rate, the average duration from presentation to publication, and the distribution of publications in the various journals. A total of 770 abstracts were presented at the annual SOMOS meetings. The overall full-text publication rate at a minimum of 3 years was 45.7% (352 publications). The average time from presentation to publication was 2.7 years. The published articles appeared in 65 peer-reviewed journals, with notable distribution in Spine (10.0%), The American Journal of Sports Medicine (9.4%), and The Journal of Bone and Joint Surgery (9.4%). The full-text publication rate of abstracts presented at the annual SOMOS meetings compares favorably with that of other major orthopaedic conferences in the United States. Nonetheless, more than half of abstracts presented at the SOMOS meetings remain unpublished.