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Journal: The American journal of sports medicine


Athletes who specialize in their sport at an early age may be at risk for burnout, overuse injury, and reduced attainment of elite status. Timing of sport specialization has not been studied in elite basketball athletes.

Concepts: High school, Basketball, Sport, High School Musical, Status attainment, National Basketball Association, American Basketball Association


BACKGROUND:High school athletes are at risk for concussions. Although a previously published study showed an increase in concussion rates for a single school district, it remains unknown if the rate of concussions among high school athletes is increasing nationally. PURPOSE:To investigate national high school athlete concussion rates over time. STUDY DESIGN:Descriptive epidemiologic study. METHODS:The rate of concussions per 1000 athlete-exposures was calculated for academic years 2005-2006 through 2011-2012 using the High School Reporting Information Online sports injury surveillance system. RESULTS:During the 7-year period of this study, High School Reporting Information Online captured 4024 concussions with overall concussion diagnosis rates increasing significantly from 0.23 to 0.51 (P = .004). Concussion diagnosis rates increased for each of the 9 sports studied, with 5 sports having statistically significant increases over this 7-year period. CONCLUSION:The study analysis indicates that national concussion diagnosis rates for high school sports have increased significantly over time.

Concepts: Time, Epidemiology, Statistics, Rates, High school, College, Biostatistics, Concussion


BACKGROUND:Lateral epicondylitis (LE) is a common musculoskeletal disorder for which an effective treatment strategy remains unknown. PURPOSE:To examine whether a single injection of platelet-rich plasma (PRP) is more effective than placebo (saline) or glucocorticoid in reducing pain in adults with LE after 3 months. STUDY DESIGN:Randomized controlled trial; Level of evidence, 1. METHODS:A total of 60 patients with chronic LE were randomized (1:1:1) to receive either a blinded injection of PRP, saline, or glucocorticoid. The primary end point was a change in pain using the Patient-Rated Tennis Elbow Evaluation (PRTEE) questionnaire at 3 months. Secondary outcomes were ultrasonographic changes in tendon thickness and color Doppler activity. RESULTS:Pain reduction at 3 months (primary end point) was observed in all 3 groups, with no statistically significant difference between the groups; mean differences were the following: glucocorticoid versus saline: -3.8 (95% CI, -9.9 to 2.4); PRP versus saline: -2.7 (95% CI, -8.8 to 3.5); and glucocorticoid versus PRP: -1.1 (95% CI, -7.2 to 5.0). At 1 month, however, glucocorticoid reduced pain more effectively than did both saline and PRP; mean differences were the following: glucocorticoid versus saline: -8.1 (95% CI, -14.3 to -1.9); and glucocorticoid versus PRP: -9.3 (95% CI, -15.4 to -3.2). Among the secondary outcomes, at 3 months, glucocorticoid was more effective than PRP and saline in reducing color Doppler activity and tendon thickness. For color Doppler activity, mean differences were the following: glucocorticoid versus PRP: -2.6 (95% CI, -3.1 to -2.2); and glucocorticoid versus saline: -2.0 (95% CI, -2.5 to -1.6). For tendon thickness, mean differences were the following: glucocorticoid versus PRP: -0.5 (95% CI, -0.8 to -0.2); and glucocorticoid versus saline: -0.8 (95% CI, -1.2 to -0.5). CONCLUSION:Neither injection of PRP nor glucocorticoid was superior to saline with regard to pain reduction in LE at the primary end point at 3 months. However, injection of glucocorticoid had a short-term pain-reducing effect at 1 month in contrast to the other therapies. Injection of glucocorticoid in LE reduces both color Doppler activity and tendon thickness compared with PRP and saline.

Concepts: Clinical trial, Statistics, Randomized controlled trial, Redox, Statistical significance, Placebo, Acupuncture, Tennis elbow


BACKGROUND:Medial ulnar collateral ligament (UCL) reconstruction is a common procedure performed on Major League Baseball (MLB) pitchers in the United States. PURPOSE:To determine (1) the rate of return to pitching (RTP) in the MLB after UCL reconstruction, (2) the RTP rate in either the MLB and minor league combined, (3) performance after RTP, and (4) the difference in the RTP rate and performance between pitchers who underwent UCL reconstruction and matched controls without UCL injuries. STUDY DESIGN:Cohort study; Level of evidence, 3. METHODS:Major League Baseball pitchers with symptomatic medial UCL deficiency who underwent UCL reconstruction were evaluated. All player, elbow, and surgical demographic data were analyzed. Controls matched by age, body mass index, position, handedness, and MLB experience and performance were selected from the MLB during the same years as those undergoing UCL reconstruction. An “index year” was designated for controls, analogous to the UCL reconstruction year in cases. Return to pitching and performance measures in the MLB were compared between cases and controls. Student t tests were performed for analysis of within-group and between-group variables, respectively. RESULTS:A total of 179 pitchers with UCL tears who underwent reconstruction met the inclusion criteria and were analyzed. Of these, 148 pitchers (83%) were able to RTP in the MLB, and 174 pitchers were able to RTP in the MLB and minor league combined (97.2%), while only 5 pitchers (2.8%) were never able to RTP in either the MLB or minor league. Pitchers returned to the MLB at a mean 20.5 ± 9.72 months after UCL reconstruction. The length of career in the MLB after UCL reconstruction was 3.9 ± 2.84 years, although 56 of these patients were still currently actively pitching in the MLB at the start of the 2013 season. The revision rate was 3.9%. In the year before UCL reconstruction, pitching performance declined significantly in the cases versus controls in the number of innings pitched, games played, and wins and the winning percentage (P < .05). After surgery, pitchers showed significantly improved performance versus before surgery (fewer losses, a lower losing percentage, lower earned run average [ERA], threw fewer walks, and allowed fewer hits, runs, and home runs) (P < .05). Comparisons between cases and controls for the time frame after UCL reconstruction (cases) or the index year (controls) demonstrated that cases had significantly (P < .05) fewer losses per season and a lower losing percentage. In addition, cases had a significantly lower ERA and allowed fewer walks and hits per inning pitched. CONCLUSION:There is a high rate of RTP in professional baseball after UCL reconstruction. Performance declined before surgery and improved after surgery. When compared with demographic-matched controls, patients who underwent UCL reconstruction had better results in multiple performance measures. Reconstruction of the UCL allows for a predictable and successful return to the MLB.

Concepts: Baseball, Baseball statistics, Major League Baseball, National League, St. Louis Cardinals, Minor league baseball, Designated hitter, Tommy John surgery


BACKGROUND:Prehabilitation is defined as preparing an individual to withstand a stressful event through enhancement of functional capacity. HYPOTHESIS:We hypothesized that a preoperative exercise program would enhance postoperative outcomes after anterior cruciate ligament reconstruction (ACLR). STUDY DESIGN:Randomized controlled clinical trial; Level of evidence, 1. METHODS:Twenty volunteers awaiting ACLR were randomly assigned to a control or exercise intervention group. The exercise group completed a 6-week gym- and home-based exercise program. Assessments include single-legged hop test; quadriceps and hamstring peak torque and magnetic resonance imaging cross-sectional area (CSA); Modified Cincinnati Knee Rating System score; and muscle biopsy of the vastus lateralis muscle completed at baseline, preoperatively, and 12 weeks postoperatively. Myosin heavy chain (MHC) isoforms protein and messenger RNA (mRNA) expression were determined with SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) and RT-PCR (real-time polymerase chain reaction), respectively; IGF-1 (insulin-like growth factor 1), MuRF-1 (muscle RING-finger protein-1), and MAFbx (muscle atrophy f-box) mRNA expression were determined with quantitative RT-PCR. RESULTS:Following 6 weeks of exercise intervention, the single-legged hop test results improved significantly in the exercise-injured limb compared with baseline (P = .001). Quadriceps peak torque in the injured limb improved with similar gains in CSA compared with baseline (P = .001). However, this was not significantly increased compared with the control group. Quadriceps and vastus medialis CSA were also larger in the exercise group than in controls (P = .0024 and P = .015, respectively). The modified Cincinnati score was better in the exercise-injured limb compared with baseline. At 12 weeks postoperatively, the rate of decline in the single-legged hop test was reduced in the exercise group compared with controls (P = .001). Similar trends were not seen for quadriceps peak torque and CSA. The vastus medialis CSA had regressed to similar levels as the control group (P = .008). The modified Cincinnati score continued to increase in the exercise group compared with controls (P = .004). The expression of the hypertrophic IGF-1 gene was significantly increased after the exercise intervention (P = .028), with a decrease back to baseline 12 weeks postoperatively (P = .012). Atrophic MuRF-1 gene expression was decreased after intervention compared with baseline (P = .05) but increased again at 12 weeks postoperatively (P = .03). The MAFbx levels did not change significantly in either group and within each time point. On the mRNA level, there was a shift from MHC-IIx isoform to MHC-IIa after exercise, with significant changes compared with control preoperatively (P = .028). Protein testing was able to reproduce this increase for MHC-IIa isoform expression only. CONCLUSION:The 6-week progressive prehabilitation program for subjects undergoing ACLR led to improved knee function based on the single-legged hop test and self-reported assessment using the modified Cincinnati score. These effects were sustained at 12 weeks postoperatively. This study supports prehabilitation as a consideration for patients awaiting ACLR; however, further studies are warranted.

Concepts: Protein, Polymerase chain reaction, Molecular biology, Messenger RNA, Muscle, Gel electrophoresis, Knee, Anterior cruciate ligament


Graft survivorship, reinjury rates, and career length are poorly understood after anterior cruciate ligament (ACL) reconstruction in the elite collegiate athlete. The purpose of this study was to examine the outcomes of ACL reconstruction in a National Collegiate Athletic Association (NCAA) Division I athlete cohort.

Concepts: Knee, Anterior cruciate ligament, College football, Ligament, Anterior cruciate ligament injury, Cruciate ligament, Division I, Ivy League


BACKGROUND:Anterior cruciate ligament (ACL) and meniscus injuries are common in female athletes participating in cutting and pivoting sports such as basketball. The epidemiological characteristics of injury in athletes seen at the Women’s National Basketball Association (WNBA) combine and the effect of ACL reconstruction and meniscus surgery on longevity in the WNBA are unknown. PURPOSE:To evaluate the details and spectrum of injuries in athletes entering the WNBA combine and to assess the potential effect of specific injuries on the round drafted into the WNBA and career length. STUDY DESIGN:Descriptive epidemiology study. METHODS:Demographic data and the documented collegiate injury profile were reviewed from the WNBA database for all players entering the WNBA combine in 2000-2008. The study included injury data on 506 athletes. Complete demographic data were available for 496 players. RESULTS:Of the athletes taking part in the combine, 45.2% were guards, 33.7% were forwards, and 21.1% were centers. Ankle sprain (47.8% of players), hand injury (20.8%), patellar tendinitis (17.0%), ACL injury (15.0%), meniscus injury (10.5%), stress fracture (7.3%), and concussion (7.1%) were the most common injuries reported. Seventy-three athletes (14.4%) reported ACL reconstruction before entering the WNBA combine, and meniscus surgery was the next most common surgery (n = 50 players; 9.9%). There were no differences in ACL or meniscus surgery when analyzed by player position or round drafted. History of ACL or meniscus surgery did not affect career length in the WNBA. Excluding ACL and meniscus surgery, other reported surgical procedures were knee arthroscopic surgery (11.7%), ankle reconstruction (2.6%), and shoulder stabilization (2.0%). CONCLUSION:The ankle is the most common site of injury and ACL reconstruction is the most common surgery in elite female athletes participating in the WNBA combine. A history of injury or surgery did not affect the round drafted or career length.

Concepts: Surgery, Knee, Anterior cruciate ligament, Injuries, Injury, Arthroscopy, Tear of meniscus, National Basketball Association


Injuries are inherent to the sport of American football and often require operative management. Outcomes have been reported for certain surgical procedures in professional athletes in the National Football League (NFL), but there is little information comparing the career effect of these procedures.

Concepts: Surgery, College football, Reconstructive surgery, Texas, American football, Football, National Football League, Super Bowl


BACKGROUND:Medial patellofemoral ligament (MPFL) reconstruction is a routine procedure for patellar instability. The majority of the techniques require hardware fixation or a bony procedure at the patella. However, most of the complications described in the literature can be attributed to patellar fixation. The “superficial quad technique” uses the superficial slip of the quadriceps tendon as the graft material, which provides a better anatomic match to the native MPFL. HYPOTHESIS:The superficial quad technique provides anatomic patellar fixation without a bony procedure and without patellar complications. STUDY DESIGN:Case series; Level of evidence, 4. METHODS:The study included 32 patients (10 male, 22 female; mean age, 25 years) who underwent MPFL reconstruction using the superficial quad technique and who were followed for a mean duration of 38 months. Objective assessment was performed and Kujala scores were obtained preoperatively and at the time of final follow-up. RESULTS:There were no patellar complications, including redislocation, in the present study. The mean Kujala score improved to 91.25 (range, 73-100) from a preoperative score of 49.31 (range, 23-62). CONCLUSION:The results were comparable with those of other studies in the literature that used hamstring grafts, but without associated patellar complications. The superficial quad technique uses graft material that is a better anatomic match to the native MPFL. It provides anatomic patellar fixation without a bony procedure.

Concepts: Better, Bone, Knee, Arithmetic mean, Grafting, Ligament, Patella, Patellar ligament


BACKGROUND:Debate exists on the proper relation of the anterior cruciate ligament (ACL) footprint with the intercondylar notch in anatomic ACL reconstructions. Patient-specific graft placement based on the inclination of the intercondylar roof has been proposed. The relationship between the intercondylar roof and native ACL footprint on the tibia has not previously been quantified. HYPOTHESIS:No statistical relationship exists between the intercondylar roof angle and the location of the native footprint of the ACL on the tibia. STUDY DESIGN:Case series; Level of evidence, 4. METHODS:Knees from 138 patients with both lateral radiographs and MRI, without a history of ligamentous injury or fracture, were reviewed to measure the intercondylar roof angle of the femur. Roof angles were measured on lateral radiographs. The MRI data of the same knees were analyzed to measure the position of the central tibial footprint of the ACL (cACL). The roof angle and tibial footprint were evaluated to determine if statistical relationships existed. RESULTS:Patients had a mean ± SD age of 40 ± 16 years. Average roof angle was 34.7° ± 5.2° (range, 23°-48°; 95% CI, 33.9°-35.5°), and it differed by sex but not by side (right/left). The cACL was 44.1% ± 3.4% (range, 36.1%-51.9%; 95% CI, 43.2%-45.0%) of the anteroposterior length of the tibia. There was only a weak correlation between the intercondylar roof angle and the cACL (R = 0.106). No significant differences arose between subpopulations of sex or side. CONCLUSION:The tibial footprint of the ACL is located in a position on the tibia that is consistent and does not vary according to intercondylar roof angle. The cACL is consistently located between 43.2% and 45.0% of the anteroposterior length of the tibia. Intercondylar roof-based guidance may not predictably place a tibial tunnel in the native ACL footprint. Use of a generic ACL footprint to place a tibial tunnel during ACL reconstruction may be reliable in up to 95% of patients.

Concepts: Knee, Anterior cruciate ligament, Ligament, Anterior cruciate ligament injury, Anterior cruciate ligament reconstruction, Cruciate ligament, Hamstring, Lateral meniscus