David M. Lintner

Efficacy of Intra-articular Platelet-Rich Plasma Injections in Knee Osteoarthritis: A Systematic Review.

PURPOSEnTo determine (1) whether platelet-rich plasma (PRP) injection significantly improves validated patient-reported outcomes in patients with symptomatic knee osteoarthritis (OA) at 6 and 12 months postinjection, (2) differences in outcomes between PRP and corticosteroid injections or viscosupplementation or placebo injections at 6 and 12 months postinjection, and (3) similarities and differences in outcomes based on the PRP formulations used in the analyzed studies.nnnMETHODSnPubMed, Cochrane Central Register of Controlled Trials, SCOPUS, and Sport Discus were searched for English-language, level I evidence, human inxa0vivo studies on the treatment of symptomatic knee OA with intra-articular PRP compared with other options, with a minimum of 6 months of follow-up. A quality assessment of all articles was performed using the Modified Coleman Methodology Score (average, 83.3/100), and outcomes were analyzed using 2-proportion z-tests.nnnRESULTSnSix articles (739 patients, 817 knees, 39% males, mean age of 59.9 years, with 38 weeks average follow-up) were analyzed. All studies met minimal clinical important difference criteria and showed significant improvements in statistical and clinical outcomes, including pain, physical function, and stiffness, with PRP. All but one study showed significant differences in clinical outcomes between PRP and hyaluronic acid (HA) or PRP and placebo in pain and function. Average pretreatment Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were 52.36 and 52.05 for the PRP and HA groups, respectively (Pxa0= .420). Mean post-treatment WOMAC scores for PRP were significantly better than for HA at 3 to 6 months (28.5 and 43.4, respectively; Pxa0= .0008) and at 6 to 12 months (22.8 and 38.1, respectively; Pxa0= .0062). None of the included studies used corticosteroids.nnnCONCLUSIONSnIn patients with symptomatic knee OA, PRP injection results in significant clinical improvements up to 12 months postinjection. Clinical outcomes and WOMAC scores are significantly better after PRP versus HA at 3 to 12 months postinjection. There is limited evidence for comparing leukocyte-rich versus leukocyte-poor PRP or PRP versus steroids in this study.nnnLEVEL OF EVIDENCEnLevel I, systematic review of Level I studies.

Return to Play After Treatment of Superior Labral Tears in Professional Baseball Players

Background: The published return-to-play (RTP) rates for athletes who have undergone surgical repair of superior labrum anterior-posterior (SLAP) tears vary widely and are generally accepted to be lower in the subset of competitive throwers. The efficacy of nonsurgical treatment for this group is unknown. Hypothesis: Nonsurgical treatment of SLAP tears in professional baseball players leads to RTP before consideration of surgical treatment. Incorporating performance statistics and level of competition will result in lower calculated RTP rates than have been previously reported. Study Design: Case series; Level of evidence, 4. Methods: A retrospective review of 119 consecutive patients in a single professional baseball organization with persistent shoulder pain that limited the ability to compete was performed. Sixty-eight patients had magnetic resonance imaging–documented SLAP lesions. All patients had failed 1 attempt at rehabilitation but had continued with supervised physical therapy. Treatment was according to an algorithm focusing on the correction of scapular dyskinesia and posterior capsular contracture with glenohumeral internal rotation deficit (GIRD), followed by pain-free return to throwing. Those who failed 2 cycles of nonsurgical treatment were treated surgically. Success was defined by 2 different standards: (1) RTP, in accordance with previous studies; and (2) a more stringent standard of return to the same level/quality of professional competition (A, AA, AAA, etc) with the incorporation of a return to preinjury individual performance statistics (earned run average, walks plus hits per inning pitched), termed “return to prior performance” (RPP). Results: Sixty-eight athletes were identified with SLAP lesions. Twenty-one pitchers successfully completed the nonsurgical algorithm and attempted a return. Their RTP rate was 40%, and their RPP rate was 22%. The RTP rate for 27 pitchers who underwent 30 procedures was 48%, and the RPP rate was 7%. For 10 position players treated nonsurgically, the RTP rate was 39%, and the RPP rate was 26%. The RTP rate for 13 position players who underwent 15 procedures was 85%, with an RPP rate of 54%. Conclusion: Nonsurgical treatment correcting scapular dyskinesia and GIRD had a reasonable success rate in professional baseball players with painful shoulders and documented SLAP lesions. The rate of return after surgical treatment of SLAP lesions was low for pitchers. The RTP and RPP rates were higher for position players than for pitchers. Nonsurgical treatment should be considered for professional baseball players with documented SLAP lesions, as it can lead to acceptable RTP and RPP rates.

Radiographic Prevalence of Dysplasia, Cam, and Pincer Deformities in Elite Ballet

Background: The demands of hip strength and motion in ballet are high. Hip disorders, such as cam and pincer deformities or dysplasia, may affect dance performance. However, the prevalence of these radiographic findings is unknown. Purpose: To determine the prevalence of radiographic cam and pincer deformities, borderline dysplasia, and dysplasia in a professional ballet company. Study Design: Cross-sectional study; Level of evidence, 3. Methods: An institutional review board–approved cross-sectional investigation of a professional ballet company was undertaken. Male and female adult dancers were eligible for inclusion. Four plain radiographs were obtained (standing anteroposterior pelvis, bilateral false profile, and supine Dunn 45°) and verified for adequacy. Cam and pincer deformities, dysplasia, borderline dysplasia, and osteoarthritis were defined. All plain radiographic parameters were measured and analyzed on available radiographs. Student t test, chi-square test (and Fisher exact test), and Spearman correlation analyses were performed to compare sexes, groups, and the effect of select radiographic criteria. Results: A total of 47 dancers were analyzed (21 males, 26 females; mean age (±SD), 23.8 ± 5.4 years). Cam deformity was identified in 25.5% (24/94) of hips and 31.9% (15/47) of subjects, with a significantly greater prevalence in male dancers than females (48% hips and 57% subjects vs 8% hips and 12% subjects; P < .001 and P = .001, respectively). Seventy-four percent of subjects had at least 2 of 6 radiographic signs of pincer deformity. Male dancers had a significantly greater prevalence of both prominent ischial spine and posterior wall signs (P = .001 and P < .001, respectively), while female dancers had a significantly greater prevalence of coxa profunda (85% female hips vs 26% male hips; P < .001). Eighty-nine percent of subjects had dysplasia or borderline dysplasia in at least 1 hip (37% dysplastic), with a significantly greater prevalence of dysplasia or borderline dysplasia in female versus male dancers (92% female hips vs 74% male hips; P < .022). Further, in those with dysplasia or borderline dysplasia, 92% of female and 82% of male dancers had bilateral findings. Conclusion: In this professional ballet company, a high prevalence of radiographic abnormalities was found, including cam and pincer deformity and dysplasia. The results also revealed several sex-related differences of these abnormalities in this unique population. The long-term implications of these findings in this group of elite athletes remain unknown, and this issue warrants future investigation.

The utility of the KJOC score in professional baseball in the United States

Background: The Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow questionnaire has been shown by previous studies to be more sensitive than other validated subjective measurement tools in the detection of upper extremity dysfunction in overhead-throwing athletes. Purpose: The primary objective was to establish normative data for KJOC scores in professional baseball players in the United States. The secondary objectives were to evaluate the effect of player age, playing position, professional competition level, history of injury, history of surgery, and time point of administration on the KJOC score. Study Design: Cross-sectional study; Level of evidence, 3. Methods: From 2011 to 2012, a total of 203 major league and minor league baseball players within the Houston Astros professional baseball organization completed the KJOC questionnaire. The questionnaire was administered at 3 time points: spring training 2011, end of season 2011, and spring training 2012. The KJOC scores were analyzed for significant differences based on player age, injury history, surgery history, fielding position, competition level, self-reported playing status, and time point of KJOC administration. Results: The average KJOC score among healthy players with no history of injury was 97.1 for major league players and 96.8 for minor league players. The time point of administration did not significantly affect the final KJOC score (P = .224), and KJOC outcomes did not vary with player age (r = −0.012; P = .867). Significantly lower average KJOC scores were reported by players with a history of upper extremity injury (86.7; P < .001) and upper extremity surgery (75.4; P < .0001). The KJOC results did vary with playing position (P = .0313), with the lowest average scores being reported by pitchers (90.9) and infielders (91.3). Conclusion: This study establishes a quantitative baseline for the future evaluation of professional baseball players with the KJOC score. Age and time of administration had no significant effect on the outcome of the KJOC score. Missed practices or games within the previous year because of injury were the most significant demographic predictors of lower KJOC scores. The KJOC score was shown to be a sensitive measurement tool for detecting subtle changes in the upper extremity performance of the professional baseball population studied.

Prevalence of Scapular Dyskinesis in Overhead and Nonoverhead Athletes: A Systematic Review

Background: Scapular dyskinesis, or abnormal dynamic scapular control, is a condition that is commonly associated with shoulder pathology but is also present in asymptomatic individuals. Literature varies on whether it represents a cause or symptom of shoulder pathology, but it is believed to be a risk factor for further injury. Clinical identification focuses on visual observation and examination maneuvers. Treatment of altered scapular motion has been shown to improve shoulder symptoms. It is thought to be more common in overhead athletes due to their reliance on unilateral upper extremity function but the incidence within nonoverhead athletes is unknown. Hypothesis: Overhead athletes will have a greater prevalence of scapular dyskinesis when compared with nonoverhead athletes. Study Design: Systematic review; Level of evidence, 3. Methods: After PROSPERO registration, a systematic review was performed using PRISMA guidelines through the PubMed database looking for studies published before October 2014. All studies containing the search terms scapular, scapulothoracic, dyskinesis, dyskinesia, shoulder athlete, or overhead athlete were included. Studies that did not include prevalence data for scapular dyskinesis were excluded. Study methodological quality was evaluated using the modified Coleman methodology score. Descriptive statistics and 2-proportion 2-tailed z-tests were used to compare the reported prevalence of scapular dyskinesis between overhead and nonoverhead athletes. Results: Twelve studies were analyzed including 1401 athletes (1257 overhead and 144 nonoverhead; mean age, 24.4 ± 7.1 years; 78% men). All the studies were evidence level 2 (33%) or level 3 (67%). The reported prevalence of scapular dyskinesis was significantly (P < .0001) higher in overhead athletes (61%) compared with nonoverhead athletes (33%). Conclusion: Scapular dyskinesis was found to have a greater reported prevalence (61%) in overhead athletes compared with nonoverhead athletes (33%). Clinical Relevance: Prevalence data for scapular dyskinesis are scarce within the literature. Information on the reported prevalence, laterality, and association with the dominant extremity will allow for better allocation of diagnostic and therapeutic interventions. Recognition and treatment will help athletes to optimize functional performance and decrease the risk of further shoulder injury.

Radiographic Evidence of Hip Microinstability in Elite Ballet

PURPOSEnTo determine prevalence, magnitude, and predisposing radiographic features of hip subluxation in elite ballet dancers.nnnMETHODSnA cross-sectional investigation of professional male and female ballet dancers was performed using 5 plain radiographs. A splits anteroposterior (AP) radiograph was performed with legs abducted parallel to the trunk in the coronal plane (splits position; grand écart facial). Hip center position (HCP) was measured on standing AP pelvis and AP pelvis splits views and the difference calculated (subluxation distance) to determine prevalence and magnitude of femoral head subluxation. Student t test compared HCP on AP pelvis and splits radiographs. Pearson correlations were used to correlate splits HCP with radiographic measures of femoroacetabular impingement and dysplasia.nnnRESULTSnAnalyzing 47 dancers (21 men, 26 women; 23.8 ± 5.4xa0years), mean HCP on standing AP pelvis was 9.39 ± 3.33xa0mm versus 10.8 ± 2.92xa0mm on splits radiograph, with mean subluxation distance of 1.41xa0mmxa0(Pxa0= .035). Forty-two dancers femoral heads translated laterally with splits positioning, and 17 dancers (36%) exhibited a vacuum sign (bilateral in 71% of subjects with at least 1 hip vacuum sign). There was strong positive correlation (rxa0= 0.461, Pxa0= .001) with splits HCP and alpha angle (Dunn 45°), and moderate negative correlation (rxa0=xa0-0.332, Pxa0= .022) with subluxation distance and neck-shaft angle. In men, splits HCP increased as lateral center edge angle (CEA) decreased (rxa0=xa0-0.437, Pxa0= .047), as anterior CEA decreased (rxa0=xa0-0.482, Pxa0= .027), as Tönnis angle increased (rxa0= 0.656, Pxa0= .001), and as femoral head extrusion index increased (rxa0= 0.511, Pxa0= .018). In women, there was moderate negative correlation (rxa0=xa0-0.389, Pxa0= .049) with subluxation distance and neck-shaft angle.nnnCONCLUSIONSnHip subluxation occurs during splits in most professional ballet dancers, with a significantly greater magnitude of subluxation in women than men. Subluxation magnitude increases with increasing alpha angle and decreasing neck-shaft angle. In men, the magnitude increases with severity of dysplasia. Women had subluxation regardless of acetabular morphology but increased subluxation with decreased neck-shaft angle. This provides radiographic support for hip microinstability in elite ballet.nnnLEVEL OF EVIDENCEnLevel IV, diagnostic.

Incidence and Prevalence of Musculoskeletal Injury in Ballet: A Systematic Review

Background Most published studies on injuries in the ballet dancer focus on the lower extremity. The rigors of this activity require special training and care. By understanding prevalence and injury pattern to the musculoskeletal system, targeted prevention and treatment for this population can be developed. Purpose To determine the incidence and prevalence of musculoskeletal injuries in ballet. Study Design Systematic review; Level of evidence, 4. Methods A systematic review registered with PROSPERO was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Level 1 through 4 evidence studies reporting incidence of musculoskeletal injuries in male and female ballet dancers were included, with the numbers and types of injuries extracted from each. Injury rates were recorded and calculated based on professional status, sex, and nature of injury. Incidence was defined as number of injuries sustained over a specific time. Prevalence was defined as proportion of subjects with an injury at a given point in time. Results The studies analyzed reported injury incidence or prevalence in more than 1365 amateur and 900 professional dancers. The mean age was 16.2 years among amateur and 27.0 years among professional dancers. The incidence of injury among amateur dancers was 0.99 and 1.09 injuries per 1000 dance hours in males and females, respectively; 75% of injuries were overuse, with similar rates among males and females. In professional dancers, the incidence of injury was 1.06 and 1.46 injuries per 1000 dance hours in males and females, respectively, and 64% of female injuries were overuse, compared with 50% in males (P < .001). Only 3 studies provided prevalence data, including 62% prevalence of lumbosacral pain, 58% painful snapping hip, and 29% patellofemoral pain. Lower extremity injuries comprised 66% to 91% of all injuries, with the foot and ankle accounting for 14% to 57%. Conclusion The overall incidence of injury among amateur and professional ballet dancers is 0.97 and 1.24 injuries per 1000 dance hours, respectively. The majority are overuse in both amateur and professional dancers, with amateur ballet dancers showing a higher proportion of overuse injuries than professionals (P < .001). Male professional dancers show a higher proportion of traumatic injuries, accounting for half of their injuries (P < .001).

The impact of ulnar collateral ligament tear and reconstruction on contact pressures in the lateral compartment of the elbow

HYPOTHESISnComplete ulnar collateral ligament (UCL) injury increases articular pressure and reduces contact area compared with the normal intact UCL. UCL reconstruction restores the contact area and contact pressure observed in the native joint.nnnMATERIALS AND METHODSnSix male cadaveric elbows were mounted on a custom jig capable of simulating the 2 critical phases of the throwing motion during pitching. A contact sensor was placed through an anterior arthrotomy into the radiocapitellar joint. Each specimen then underwent valgus loading at 1.75 and 5.25 Nm of torque with the biceps, brachialis, and triceps under axial load in each testing condition.nnnRESULTSnThe average valgus laxity in the intact elbow at 90° was 3.7° ± 0.6° at the 5.25 Nm level of torque, which doubled after transection. The reconstruction group demonstrated less laxity (2.4° ± 0.4°) and reduced valgus angulation of the ulna at 5.25 Nm of torque. The transected UCL condition showed peak contact pressure 67% higher compared with the native ligament group at 5.25 Nm of torque. The reconstructed group increased peak articular cartilage pressures by 33% from the native ligament. At 5.25 Nm of torque for the 90° flexion phase, the transected UCL condition showed an average contact pressure of 84% greater than that of the native ligament group. Reconstruction of the UCL restored average articular pressures to within 20% of intact values at 90°.nnnCONCLUSIONnUCL injury increases radiocapitellar contact pressures and reduces resistance of the elbow to valgus loading. Contact pressures and valgus laxity can be improved with UCL reconstruction.nnnDISCUSSIONnTaken as a whole, the peak pressure data indicate that the reconstruction restores valgus stability and lateral contact pressures to nearly normal levels under the conditions tested. Because the 90 position is the clinically significant position, these laboratory data support the clinical success of the docking procedure.

The Cost-Effectiveness of Anterior Cruciate Ligament Reconstruction in Competitive Athletes

Background: Competitive athletes value the ability to return to competitive play after the treatment of anterior cruciate ligament (ACL) injuries. ACL reconstruction has high success rates for return to play, but some studies indicate that patients may do well with nonoperative physical therapy treatment. Purpose: To evaluate the cost-effectiveness of the treatment of acute ACL tears with either initial surgical reconstruction or physical therapy in competitive athletes. Study Design: Economic and decision analysis; Level of evidence, 2. Methods: The incremental cost, incremental effectiveness, and incremental cost-effectiveness ratio (ICER) of ACL reconstruction compared with physical therapy were calculated from a cost-effectiveness analysis of ACL reconstruction compared with physical therapy for the initial management of acute ACL injuries in competitive athletes. The ACL reconstruction strategy and the physical therapy strategy were represented as Markov models. Costs and quality-adjusted life-years (QALYs) were evaluated over a 6-year time horizon and were analyzed from a societal perspective. Quality of life and probabilities of clinical outcomes were obtained from the peer-reviewed literature, and costs were compiled from a large academic hospital in the United States. One-way, 2-way, and probabilistic sensitivity analyses were used to assess the effect of uncertainty in variables on the ICER of ACL reconstruction. Results: The ICER of ACL reconstruction compared with physical therapy was

Asymmetric Hip Rotation in Professional Baseball Pitchers

22,702 per QALY gained. The ICER was most sensitive to the quality of life of returning to play or not returning to play, costs, and duration of follow-up but relatively insensitive to the rates and costs of complications, probabilities of return to play for both operative and nonoperative treatments, and discount rate. Conclusion: ACL reconstruction is a cost-effective strategy for competitive athletes with an ACL injury.