Concussion Incidence and Impact on Player Performance in Major League Baseball Players Before and After a Standardized Concussion Protocol.

BACKGROUND: Sports-related concussions have garnered significant attention in recent years because of the negative effects they can have on a player's cognitive health and performance. In response to this growing concern, Major League Baseball (MLB) introduced a standardized concussion protocol during the 2011-2012 season. PURPOSE/HYPOTHESIS: The purpose of this study was to compare the reported incidence of concussions and the subsequent performance of MLB players before and after the introduction of the standardized concussion protocol. We hypothesized that the introduction of the standardized concussion protocol would not have an impact on player performance postconcussion. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Players who suffered a concussion between 2001 and 2018 were identified from the MLB transactions page. Incidence and player performance were compared before and after the introduction of the standardized concussion protocol. Player performance was evaluated using traditional data and sabermetric data, which are advanced statistics used in conjunction with standard statistics to better compare players and teams. Player averages were calculated and compared using paired t tests for 30 days before and after concussion, 1 year before and after concussion, and career before and after concussion. Averages were also compared before and after the institution of the standardized concussion protocol using independent-measures t tests. RESULTS: There were a total of 114 players who suffered 142 concussions, with 77% of those occurring after the introduction of the concussion protocol (32 before, 110 after). The average time missed because of concussion significantly decreased from 33.7 days (range, 10-122 days) to 18.9 days (range, 6-111 days) after the concussion protocol (P = .0005). There was no difference in player performance (including batting average, on-base percentage, and slugging for batters; earned run average, fielding-independent pitching, and walks plus hits per inning pitched for pitchers) after concussion at any time point (30 days, 1 year, or career) when comparing these statistics before versus after the MLB concussion protocol. However, batter performance was significantly poorer 1 year after concussion and over the remainder of the players' careers (P < .05). CONCLUSION: The number of reported concussions increased after the introduction of the MLB concussion protocol. However, players spent significantly less time on the disabled list without any adverse effect on player performance. Despite these changes, long-term batting performance was significantly poorer after concussion.

A qualitative assessment of return to sport following ulnar collateral ligament reconstruction in baseball players.

BACKGROUND: The rate of ulnar collateral ligament (UCL) reconstruction has been increasing at all levels of play. With excellent outcomes, primary UCL reconstruction has allowed many overhead athletes to return to their pre-injury sport. However, the subjective factors influencing this decision to return to sport have yet to be studied. The aim of this study is to understand the factors influencing an athlete's decision to return to pre-injury level of sport after primary UCL reconstruction. METHODS: An experienced interviewer conducted qualitative, semi-structured interviews of patients aged 18-35 years who had undergone primary UCL reconstruction by one fellowship-trained, Major League Baseball (MLB) team orthopaedic surgeon. All subjects were throwing athletes prior to injury and had a minimum two-year follow-up without revisions. Qualitative analysis was then performed to derive codes, categories, and themes. Patients were surveyed to assess familiarity with UCL reconstruction as well as to obtain Kerlan-Jobe Orthopaedic Clinic (KJOC) Overhead Athlete Shoulder and Elbow score, American Shoulder and Elbow Surgeons Shoulder (ASES) score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) highlighting current activity and function levels along with sport participation. RESULTS: Twenty-two athletes were interviewed to elucidate four predominant themes influencing their return to sport: trust in surgeon and care team, innate drive and optimism, misconceptions regarding post-operative athletic ability, and life priorities. A significant difference was noted between patients that returned and those that did not in the KJOC survey and for the statement that UCL reconstruction surgery would improve throwing ability relative to patients' peak performance three years prior to the surgery. Athletes who did not return to sport cited lifestyle changes and age as limiting factors. CONCLUSION: Patients' decision to return to their pre-injury level of sport after primary UCL reconstruction was based on trust in their care team's reputation, intrinsic personality traits, anecdotal evidence about post-operative outcomes, and lifestyle. This study emphasizes the importance for health care providers to educate patients toward realistic expectations upon return to sport. On a larger scale, this study illustrates the effects the media and anecdotal experiences of a growing population of players undergoing UCL reconstruction have had on the game of baseball and players' decisions to return to sport. LEVEL OF EVIDENCE: Level IV.

Assessment of Flexion Strength Following Single- Versus Double-Hamstring Tendon Harvest for Anterior Cruciate Ligament Reconstruction.

PURPOSE: To compare isometric hamstring strength deficits, knee laxity, functional outcomes, and patient-reported outcomes between patients who underwent anterior cruciate ligament (ACL) reconstruction with doubled semitendinosus and gracilis tendon autograft (ST/G) versus quadrupled semitendinosus autograft (ST), at a minimum follow-up of 1-year postoperatively. METHODS: Patients who underwent ACL reconstruction with ST/G or ST hamstring autografts were retrospectively identified. Isometric hamstring strength was tested with a hand-held dynamometer at 30, 60, and 90° of knee flexion. Anterior knee laxity was assessed using a KT-1000 arthrometer. Functional outcomes were collected using the single-leg hop test and single-leg squat test. Side-to-side differences were determined and compared between the ST/G and ST groups. Patient-reported outcomes were collected on all patients. RESULTS: Eighty-four patients who underwent ST/G (n = 34) or ST (n = 50) autograft ACL reconstruction were recruited to participate in this study. There was no difference in knee laxity between the groups. Side-to-side hamstring strength deficits increased with increased flexion angles. At 90° of flexion, the ST/G group had a significantly greater flexion strength deficit compared with the ST group (37.8 ± 15.1% vs 24.7 ± 12.5%, P < .001). Aside from a significant difference in the KOOS pain Score (P .045), no other significant differences in functional or patient reported outcomes between the groups were identified. CONCLUSIONS: Patients who underwent ACL reconstruction with ST/G compared with ST autograft have a significantly greater isometric flexion strength deficit at 90° of flexion. Future investigations are required to determine the clinical relevance of this difference and whether specialized therapy protocols can mitigate this deficit. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Subscapularis Myotendinous Junction Tears Presenting with Posterior Shoulder Pain in Overhead Throwing Athletes.

OBJECTIVE: Acute inferior subscapularis myotendinous junction injuries are occasionally seen in overhead throwing athletes, and can present with posterior shoulder pain. CASE REPORTS: Four professional baseball pitchers presented with acute onset of posterior shoulder pain while pitching. After thorough, routine physical examination of the shoulder by the referring orthopaedic surgeon magnetic resonance imaging (MRI) was performed within 7-10 days of the onset of presenting symptoms and interpreted in consensus by 2 fellowshiptrained musculoskeletal radiologists with 9 and 5 years of experience and a musculoskeletal radiology fellow. The patients were then treated conservatively for subscapularis musculotendinous injuries and clinically assessed for symptom resolution before they were allowed to return to play. CONCLUSION: Inferior subscapularis myotendinous junction injuries should be included in the differential diagnosis of baseball pitchers with posterior shoulder pain.

Complete Intrasubstance Long Head Biceps Brachii Rupture with Successful Repair: A Case Report.

INTRODUCTION: Intrasubstance biceps brachii rupture is a rare injury. Non-operative management of this injury has demonstrated worse outcomes than early operative intervention. CASE REPORT: We report a case of a traumatic long head of the biceps brachii muscle belly rupture repaired primarily throughthe Kragh technique augmented with human dermal collagen matrix. The patient demonstrated full strength, an intact repair throughclinical exam and magnetic resonance imaging at 6-year follow-up. Dash scoring demonstrated 0 (no disability) out of 100 at this time. CONCLUSION: Repair of acute traumatic closed transection of the biceps brachii can be successfully repaired utilizing this technique with excellent post-operative function.

Influence of Pitching Release Location on Ulnar Collateral Ligament Reconstruction Risk Among Major League Baseball Pitchers.

BACKGROUND: Medial ulnar collateral ligament (UCL) reconstruction is a common procedure performed among Major League Baseball (MLB) pitchers. The etiology of UCL injury is complex and is not entirely understood. HYPOTHESIS: To better understand risk factors for requiring UCL reconstruction, we hypothesized that pitchers who eventually undergo the procedure will exhibit different throwing mechanics as measured by pitch-tracking data points, such as velocity and release location. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Pitch-tracking and demographic data were gathered for 140 MLB pitchers who had undergone UCL reconstruction between the 2010 and 2017 seasons. Pitch type, release location, and velocity were compared between the surgical cohort and a matched-control cohort. RESULTS: When compared with controls, the mean pitch release location for pitchers who required UCL reconstruction was 12.2 cm more lateral in the year immediately preceding surgery (P = .001). Furthermore, within the surgical cohort, the horizontal release location was 3.4 cm more lateral immediately preceding surgery compared with 2 years earlier (P = .036). Binary logistic regression indicated an odds ratio of 0.51, suggesting a roughly 5% increased odds of UCL reconstruction for every 10 cm of increased lateral release location (P = .048). Both the surgical and the control cohorts threw similar rates of fastballs and had similar mean pitch velocity and fastball velocity. Control pitchers displayed a significant decrease over time in mean pitch velocity (P = .005) and mean fastball velocity, while pitchers in the UCL reconstruction cohort did not (P = .012). CONCLUSION: Pitch tracking indicates that the mean release point is more lateral in pitchers preceding UCL reconstruction as compared with controls, suggesting that a more lateral pitch release location is an independent risk factor for UCL injury and reconstruction.

Changes in pitching mechanics after ulnar collateral ligament reconstruction in major league baseball pitchers.

BACKGROUND: Medial ulnar collateral ligament (UCL) reconstruction is a common procedure performed on Major League Baseball pitchers. Variations in pitching mechanics before and after UCL reconstructive surgery are not well understood. METHODS: Publicly available pitch tracking data (PITCHf/x) were compared for all Major League Baseball pitchers who underwent UCL reconstruction between 2008 and 2013. Specific parameters analyzed were fastball percentage, release location, velocity, and movement of each pitch type. These data were compared before and after UCL reconstructive surgery and compared with a randomly selected control cohort. RESULTS: There were no statistically significant changes in pitch selection or pitch accuracy after UCL reconstruction, nor was there a decrease in pitch velocity. The average pitch release location for 4-seam and 2-seam fastballs, curveballs, and changeups is more medial after UCL reconstruction (P < .01). Four-seam fastballs and sliders showed decreased horizontal breaking movement after surgery (P < .05), whereas curveballs showed increased downward breaking movement after surgery (P < .05). CONCLUSIONS: Pitch selection, pitch velocity, and pitch accuracy do not significantly change after UCL reconstruction, nor do players who require UCL reconstruction have significantly different pitch selection, velocity, or accuracy than a randomly selected control cohort. Pitch release location is more medial after UCL reconstruction for all pitch types except sliders. Breaking movement of fastballs, sliders, and curveballs changes after UCL reconstruction.

The thrower's elbow.

Overhead throwing activities expose the elbow to tremendous valgus stress, making athletes vulnerable to a specific constellation of injuries. Although baseball players, in particular pitchers, are the athletes affected most commonly, overhead throwing athletes in football, volleyball, tennis, and javelin tossing also are affected. The purpose of this review is to review the anatomy, biomechanics, pathophysiology, and treatment of elbow disorders related to overhead throwing athletes. Although focus is on management of ulnar collateral ligament injuries, all common pathologies are discussed.

Efficacy of preoperative home use of 2% chlorhexidine gluconate cloth before shoulder surgery.

HYPOTHESIS: Deep infection after shoulder surgery is a rare but devastating problem. This study tested the hypothesis that the home application of a 2% chlorhexidine gluconate cloth before shoulder surgery would be more efficacious than a standard shower of soap and water at decreasing the preoperative cutaneous levels of pathogenic bacteria on the shoulder. MATERIALS AND METHODS: This randomized, prospective study evaluated 100 consecutive patients undergoing shoulder surgery. Patients were randomly assigned to use 2% chlorhexidine gluconate-impregnated cloths (treatment group) or to shower with soap and water before surgery (control group). Cutaneous cultures were taken from the patients'shoulders in the preoperative holding area. Patients were monitored for 2 months postoperatively for clinical signs of infection. RESULTS: In the treatment group vs the control group, the overall positive culture rate was 66% vs 94% (P = .0008), and the positive culture rate for coagulase-negative Staphylococcus was 30% vs 70% (P = .0001). The positive culture rate for Propionibacterium acnes was 46% in the treatment group vs 58% in the control group (P = .32). No infections occurred in any patients at a minimum of 2-months after surgery. DISCUSSION: The use of the 2% chlorhexidine cloth was effective at decreasing overall bacterial culture rates before shoulder surgery and was particularly effective at decreasing the quantity of coagulase-negative Staphylococcus, a known causative agent of postoperative shoulder infections. CONCLUSION: Use of chlorhexidine impregnated cloths prior to shoulder surgery may be a useful adjunct to presently used infection prevention strategies.

The Professional Athlete Spine Initiative: outcomes after lumbar disc herniation in 342 elite professional athletes.

BACKGROUND CONTEXT: Although clinical outcomes after lumbar disc herniations (LDHs) in the general population have been well studied, those in elite professional athletes have not. Because these athletes have different measures of success, studies on long-term outcomes in this patient population are necessary. PURPOSE: This study seeks to define the outcomes after an LDH in a large cohort of professional athletes of American football, baseball, hockey, and basketball. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: A total of 342 professional athletes from four major North American sports from 1972 to 2008 diagnosed with an LDH were identified via a previously published protocol. Two hundred twenty-six players underwent lumbar discectomy, and 116 athletes were treated nonoperatively. Only those players who had at least 2 years of follow-up were included. OUTCOME MEASURES: Functional outcome measures as defined by successful return-to-play (RTP), career games, and years played for each player cohort were recorded both before and after treatment. Conversion factors based on games/regular season and expected career length (based on individual sport) were used to standardize the outcomes across each sport. METHODS: Using Statistical Analysis Software v. 9.1, outcome measures were compared in each cohort both before and after treatment using linear and mixed regression analyses and Cox proportional hazards models. A Kaplan-Meier survivorship curve was calculated for career length after injury. Statistical significance was defined as p<.05. RESULTS: After the diagnosis of an LDH, professional athletes successfully returned to sport 82% of the time, with an average career length of 3.4 years. Of the 226 patients who underwent surgical treatment, 184 successfully returned to play (81%), on average, for 3.3 years after surgery. Survivorship analysis demonstrated that 62.3% of players were expected to remain active 2 years after diagnosis. There were no statistically significant differences in outcome in the surgical and nonoperative cohorts. Age at diagnosis was a negative predictor of career length after injury, whereas games played before injury had a positive effect on outcome after injury. Major League Baseball (MLB) players demonstrated a significantly higher RTP rate than those of other sports, and conversely, National Football League (NFL) athletes had a lower RTP rate than players of other sports (p<.05). However, the greatest positive treatment effect from surgery for LDH was seen in NFL players, whereas for MLB athletes, a lumbar discectomy led to a shorter career compared with the nonoperative cohort (p<.05). CONCLUSIONS: Professional athletes diagnosed with an LDH successfully returned to play at a high rate with productive careers after injury. Whereas older athletes have a shorter career length after diagnosis of LDH, experienced players (high number of games played) demonstrate more games played after treatment than inexperienced athletes. Notably, surgical treatment in baseball players led to significantly shorter careers, whereas for NFL athletes, posttreatment careers were longer than those of the corresponding nonoperative cohort. The explanation for this is likely multifactorial, including the age at diagnosis, respective contractual obligations, and different physical demands imposed by each individual professional sport.

Efficacy of surgical preparation solutions in shoulder surgery.

BACKGROUND: Deep infection following shoulder surgery is a rare but devastating problem. The use of an effective skin-preparation solution may be an important step in preventing infection. The purposes of the present study were to examine the native bacteria around the shoulder and to determine the efficacy of three different surgical skin-preparation solutions on the eradication of bacteria from the shoulder. METHODS: A prospective study was undertaken to evaluate 150 consecutive patients undergoing shoulder surgery at one institution. Each shoulder was prepared with one of three randomly selected solutions: ChloraPrep (2% chlorhexidine gluconate and 70% isopropyl alcohol), DuraPrep (0.7% iodophor and 74% isopropyl alcohol), or povidone-iodine scrub and paint (0.75% iodine scrub and 1.0% iodine paint). Aerobic and anaerobic cultures were obtained prior to skin preparation for the first twenty patients, to determine the native bacteria around the shoulder, and following skin preparation for all patients. RESULTS: Coagulase-negative Staphylococcus and Propionibacterium acnes were the most commonly isolated organisms prior to skin preparation. The overall rate of positive cultures was 31% in the povidone-iodine group, 19% in the DuraPrep group, and 7% in the ChloraPrep group. The positive culture rate for the ChloraPrep group was lower than that for the povidone-iodine group (p < 0.0001) and the DuraPrep group (p = 0.01). ChloraPrep and DuraPrep were more effective than povidone-iodine in eliminating coagulase-negative Staphylococcus from the shoulder region (p < 0.001 for both). No significant difference was detected among the agents in their ability to eliminate Propionibacterium acnes from the shoulder region. No infections occurred in any of the patients treated in this study at a minimum of ten months of follow-up. CONCLUSIONS: ChloraPrep is more effective than DuraPrep and povidone-iodine at eliminating overall bacteria from the shoulder region. Both ChloraPrep and DuraPrep are more effective than povidone-iodine at eliminating coagulase-negative Staphylococcus from the shoulder.