Citations

Background: Although restricted hip range of motion (ROM) is associated with an increased risk for injuries in baseball players, the evolution of hip ROM over the season remains undefined. Hypothesis: Hip ROM profiles would be symmetric between hips and positions (pitchers vs position players) but would decrease from preseason to postseason. Additionally, it was hypothesized that this decrease in motion would correlate with workload. Study Design: Cohort study; Level of evidence, 2. Methods: Bilateral hip ROM was assessed in 96 professional baseball players (54 pitchers, 42 position players) preseason and postseason. ROM comparisons were made between lead and trailing hips, pitchers and position players, and preseason and postseason measures. The change from preseason to postseason was correlated with player demographics and measures of workload for pitchers and position players. Results: Preseason hip ROM was symmetric between hips; however, pitchers demonstrated increased preseason lead hip internal rotation (IR) ( P = .018) and bilateral hip total ROM (TROM) ( P < .020) compared with position players. From preseason to postseason, position players lost 7° of external rotation (ER) ( P ≤ .005 ). In pitchers, the loss of IR correlated with increased pitches ( P = .016) and innings ( P = .037), while the loss of ER ( P = .005 ) and TROM ( P = .014) correlated with increasing mean fastball velocity. Workload for position players did not correlate with motion loss. Conclusion: Symmetric hip ROM profiles should be anticipated in baseball players; however, pitchers may have increased preseason IR and TROM and postseason ER and TROM relative to position players. Although loss of motion correlated with workload in pitchers, this was not the case for position players. Hip motion should be monitored over the course of the season. This is particularly true for pitchers who lose IR as workload increases, which may place them at a greater risk for injuries.

Purpose The primary aims of this work were to (1) describe normal range of motion (ROM) profiles for elite pitchers, (2) describe the characteristics of shoulder and elbow injuries in professional pitchers over a 6‐year period in one Major League Baseball organization, and (3) identify ROM measures that were independently associated with a future shoulder or elbow injury. Methods Over 6 seasons (2010‐2015), a preseason assessment was performed on all pitchers invited to Major League Baseball Spring Training for a single organization. ROM measures included shoulder flexion, horizontal adduction, external rotation (ER), internal rotation, as well as elbow flexion and extension, were measured for both the dominant and nondominant arm, and total range of motion and deficits were calculated. All noncontact shoulder and elbow injuries were identified. Using multivariate binomial logistic regression analysis to control for age, height, weight, and all other ROM measures, the factors associated with an increased risk of subsequent shoulder or elbow injury were identified. Results A total of 53 shoulder (n = 25) and elbow (n = 28) injuries occurred during 132 pitcher seasons (n = 81 pitchers). The most significant categorical risk factor associated with increased elbow injury rates was the presence of a shoulder flexion deficit >5° (odds ratio [OR] 2.83; P = .042). For continuous variables, the risk of elbow injury increased by 7% for each degree of increased shoulder ER deficit (OR 1.07; P = .030) and 9% for each degree of decreased shoulder flexion (OR 1.09; P = .017). None of the measures significantly correlated with shoulder injuries. Conclusions Preseason shoulder ER and flexion deficits are independent risk factors for the development of elbow injuries during the upcoming season. Although prior work has supported the importance of reducing glenohumeral internal rotation deficits in pitchers, this study demonstrates that deficits in shoulder ER and flexion are more significant predictors of subsequent elbow injury. Level of Evidence Level III, retrospective comparative study.

Background: Following anterior cruciate ligament (ACL) reconstruction, the mechanical loading of the tissues has a significant impact on tendon-to-bone healing. The purpose of this study was to determine the effect of the timing of the initiation of mechanical loading on healing of a tendon graft in a bone tunnel. Methods: ACL reconstruction using a flexor tendon autograft was performed in 56 mice randomized to 4 groups with differing times to initiation of postoperative mechanical loading: (1) immediate, (2) 5 days, (3) 10 days, or (4) 21 days following surgery. An external fixator was placed across the knee at the time of surgery and removed when mechanical loading was scheduled to commence. Following removal of the external fixator, animals were permitted free, unrestricted cage activity. All mice were killed on postoperative day 28, and tendon-to-bone healing was assessed by biomechanical testing, microcomputed tomography (micro-CT), and histological analysis. Results: The mean failure force (and standard deviation) of the reconstructed ACL at the time of sacrifice was highest for Group 2 (3.29 ± 0.68 N) compared with Groups 1, 3, and 4 (p = 0.008). Micro-CT bone volume fraction was greatest for Group 2 in the femoral tunnel (p = 0.001), tibial tunnel (p = 0.063), and both bones (p < 0.001). Similarly, histological analysis demonstrated a narrower scar tissue interface and increased direct contact at the tendon-bone interface (p = 0.012) for Group 2. Conclusions: Following ACL reconstruction, a defined period of immobilization without weight-bearing appears to improve biomechanical strength of the healing tendon-bone interface, while prolonged periods without mechanical load and motion decrease the ultimate load to failure in this murine model. Clinical Relevance: The ideal period of restricted weight-bearing and motion following ACL reconstruction remains undefined. In a murine model, improved healing was noted for animals immobilized for a brief period of 5 days. This work may serve as an initial step in determining the ideal time period in a clinical population.

Purpose To evaluate the association of preoperative intra‐articular hip injection with surgical site infection after hip arthroscopy. Methods A large administrative database was used to identify all patients undergoing hip arthroscopy from 2007 to 2015 within a single private insurer and from 2005 to 2012 within Medicare in the United States. Those that received an ipsilateral preoperative intra‐articular hip injection were identified. The patients were then divided into the following groups based on the interval between preoperative injection and ipsilateral hip arthroscopy: (1) <3 months, (2) 3 to 6 months, and (3) 6 to 12 months. These groups were compared to a control group composed of patients with no history or a remote history (>12 months) of preoperative hip injection. Patients developing a surgical site infection within 6 months following hip arthroscopy were identified using International Classification of Diseases, Ninth Revision, and Current Procedural Terminology codes associated with infection. Groups were compared using a multivariate logistic regression analysis to control for age, gender, body mass index, smoking status, alcohol usage, and multiple medical comorbidities including diabetes mellitus, hemodialysis use, inflammatory arthritis, and peripheral vascular disease. Results In total, 19% of privately insured and 6% of Medicare patients received a hip injection within 12 months of hip arthroscopy. The overall infection rate in privately insured and Medicare patients was 1.19% and 1.10%, respectively. Preoperative hip injection within 3 months of surgery was associated with a significantly higher risk of postoperative infection versus controls (2.16%, odds ratio [OR] 6.1, P < .001, for privately insured group; 2.80%, OR 1.99, P = .037, for Medicare group). In contrast, preoperative hip injection given after more than 3 months of surgery was not associated with an increased risk of postoperative infection versus controls. Conclusions Risk of infection after hip arthroscopy increased when preoperative intra‐articular hip injections were given within 3 months of surgery. Level of Evidence Level III, retrospective comparative study.

Abstract Reconstruction of the lateral ulnar collateral ligament of the elbow is the primary treatment for recurrent symptomatic posterolateral rotatory instability. Although a number of lateral ulnar collateral ligament reconstruction techniques have been described, the docking technique has received general acceptance. In this technique, the graft is passed through a tunnel on the ulnar side and the 2 free limbs are docked into the humerus at the isometric point on the lateral condyle. Advantages of this method of reconstruction include reduced bone removal, decreased soft tissue damage, and precise control of graft tensioning. When precise surgical steps are followed, this technique can be performed in a reliable, efficient, and reproducible manner for patients with posterolateral rotatory instability of the elbow. Technique Video video See video under supplementary data.

Background: Although sliding occurs frequently in professional baseball, little is known about the epidemiology and effect of injuries that occur during sliding in this population of elite athletes. Purpose: To describe the incidence and characteristics of sliding injuries, determine their effect in terms of time out of play, and identify common injury patterns that may represent appropriate targets for injury prevention programs in the future. Study Design: Descriptive epidemiologic study. Methods: All offensive sliding injuries occurring in Major League Baseball (MLB) and Minor League Baseball (MLB) that resulted in time out of play during a span of 5 seasons (2011-2015) were identified. In addition to player demographics, data extracted included time out of play, location on field where injury occurred, level of play, treatment (surgical vs nonsurgical), direction of slide (head vs feet first), body region injured, and diagnosis. Descriptive statistics were used to describe the distribution of these injuries, and injury rates were calculated per slide. Results: From 2011 to 2015, 1633 injuries occurred as a result of a slide. The total number of days missed per season was 4263. Surgical intervention was required for 134 (8.2%) injuries, and the mean days missed was 66.5 for players treated surgically and 12.3 days for players treated nonoperatively ( P < .001). MLB players were more likely than MiLB players to require surgical intervention (12.3% vs 7.5%, P = .019). Injuries to the hands/fingers represented 25.3% of all injuries and 31.3% of those requiring surgery. Although the majority of injuries occurred at second base (57%), the per-slide injury rate was similar across all bases ( P = .991). The estimated overall frequency of injury in MLB was once per every 336 slides, and the rate of injury for head- and feet-first slides was 1 in 249 and 413 slides, respectively ( P = .119). Conclusion: Injuries occurring while sliding in professional baseball result in a significant amount of time out of play for these elite athletes. Injuries occurring at second base and those occurring to the hands and fingers were most prevalent and may be an appropriate target for future injury prevention programs.

Purpose To use a national database to determine (1) the incidence of joint infection after elbow arthroscopy, (2) identify independent patient‐related risk factors for infection, and (3) determine the influence of concomitant intra‐articular corticosteroid injection on infection risk. Methods The 100% Medicare Standard Analytic Files were queried to identify patients who underwent elbow arthroscopy from 2005 to 2012. Postoperative elbow infections occurring within 6 months of surgery were identified using both International Classification of Diseases, 9th Revision codes for postoperative infection and Current Procedural Terminology codes for the surgical treatment of a postoperative infection. Patients were excluded if their initial arthroscopic procedure was performed for infection. A multivariate binomial logistic regression analysis was then used to evaluate patient‐related risk factors for postoperative infection. Results Of the 2,704 elbow arthroscopy cases identified, 42 (1.55%) developed a postoperative infection. The annual incidence of infections did not increase significantly over the course of the study ( P = .374). A number of patient demographics and medical comorbidities significantly increased the risk of infection. The most notable factors included age ≥ 65 years (odds ratio [OR] 2.38, P = .006), body mass index > 40 (OR 1.97, P = .024), tobacco usage (OR 1.80, P = .046), alcohol usage (OR 4.01, P < .001), diabetes mellitus (OR 2.10, P = .015), inflammatory arthritis (OR 2.81, P < .001), hypercoagulable disorder (OR 2.51, P = .015), and intra‐articular corticosteroid injection at the time of arthroscopy (OR 2.79, P = .006). Conclusions The annual number of elbow arthroscopies performed in the United States has increased steadily; however, the postoperative infection rate remained consistently low at 1.55%. There are a number of patient‐specific risk factors that increase this risk with OR ranging from 1.97 to 4.01. Similarly, patients who receive an intra‐articular corticosteroid injection at the time of surgery are nearly 3 times (OR 2.79) more likely to develop a postoperative infection. Level of Evidence Level III, case‐control study.

Abstract Posterolateral rotatory instability (PLRI) is the most commonly encountered pattern of elbow instability. It is the result of disruption of the lateral collateral ligament complex leading to a posterolateral rotatory subluxation of the ulna and radial head. A number of examination maneuvers have been described to assist in clinical identification of PLRI. Despite this, some inconsistency in the description of these techniques remains in the orthopaedic literature. This Technical Note details the mechanism of injury and patient presentation, and emphasizes the primacy of the posterolateral rotatory drawer test in the assessment of PLRI while providing video instruction on how it should be performed. Technique Video video See video under supplementary data.

Abstract Currently, a number of examination and imaging techniques exist for diagnosing posterolateral rotatory instability of the elbow. Although the posterolateral rotatory drawer is the primary examination maneuver, other special tests include the lateral pivot‐shift test, prone push‐up test, chair push‐up test, and tabletop push‐up test. In addition, posterolateral rotatory instability can be evaluated using radiography, magnetic resonance imaging, dynamic fluoroscopy, or dynamic ultrasound. In this Technical Note, each of these tests is described in detail. Video instruction is also provided to further explain the techniques and provide examples of positive tests. Technique Video video See video under supplementary data.

Background: Oblique injuries are known to be a common cause of time out of play for professional baseball players, and prior work has suggested that injury rates may be on the rise in Major League Baseball (MLB). Purpose: To better understand the current incidence of oblique injuries, determine their impact based on time out of play, and to identify common injury patterns that may guide future injury prevention programs. Study Design: Descriptive epidemiological study. Methods: Using the MLB Health and Injury Tracking System, all oblique injuries that resulted in time out of play in MLB and Minor League Baseball (MiLB) during the 2011 to 2015 seasons were identified. Player demographics such as age, position/role, and handedness were included. Injury-specific factors analyzed included the following: date of injury, timing during season, days missed, mechanism, side, treatment, and reinjury status. Results: A total of 996 oblique injuries occurred in 259 (26%) MLB and 737 (74%) MiLB players. Although the injury rate was steady in MiLB, the MLB injury rate declined ( P = .037). A total of 22,064 days were missed at a mean rate of 4413 days per season and 22.2 days per injury. The majority of these occurred during batting (n = 455, 46%) or pitching (n = 348, 35%), with pitchers losing 5 days more per injury than batters ( P < .001). The leading side was injured in 77% of cases and took 5 days longer to recover from than trailing side injuries ( P = .009). Seventy-nine (7.9%) players received either a corticosteroid or platelet-rich plasma injection, and the mean recovery time was 11 days longer compared with those who did not receive an injection ( P < .001). Conclusion: Although the rate of abdominal oblique injuries is on the decline in MLB, this is not the case for MiLB, and these injuries continue to represent a significant source of time out of play in professional baseball. The vast majority of injuries occur on the lead side, and these injuries result in the greatest amount time out of play. The benefit of injections for the treatment of oblique injuries remains unknown.