Search

Context: Improper baseball pitching biomechanics are associated with increased stresses on the throwing elbow and shoulder as well as an increased risk of injury., Evidence Acquisition: Previous studies quantifying pitching kinematics and kinetics were reviewed., Study Design: Clinical review., Level of Evidence: Level 5., Results: At the instant of lead foot contact, the elbow should be flexed approximately 90° with the shoulder at about 90° abduction, 20° horizontal abduction, and 45° external rotation. The stride length should be about 85% of the pitcher's height with the lead foot in a slightly closed position. The pelvis should be rotated slightly open toward home plate with the upper torso in line with the pitching direction. Improper shoulder external rotation at foot contact is associated with increased elbow and shoulder torques and forces and may be corrected by changing the stride length and/or arm path. From foot contact to maximum shoulder external rotation to ball release, the pitcher should demonstrate a kinematic chain of lead knee extension, pelvis rotation, upper trunk rotation, elbow extension, and shoulder internal rotation. The lead knee should be flexed about 45° at foot contact and 30° at ball release. Corrective strategies for insufficient knee extension may involve technical issues (stride length, lead foot position, lead foot orientation) and/or strength and conditioning of the lower body. Improper pelvis and upper trunk rotation often indicate the need for core strength and flexibility. Maximum shoulder external rotation should be about 170°. Insufficient external rotation leads to low shoulder internal rotation velocity and low ball velocity. Deviation from 90° abduction decreases the ability to achieve maximum external rotation, increases elbow torque, and decreases the dynamic stability in the glenohumeral joint., Conclusion: Improved pitching biomechanics can increase performance and reduce risk of injury., Sort: Level C.

Background: Alterations in glenohumeral internal rotation (GIR), glenohumeral external rotation (GER), and the total arc of motion (TAM) have been linked with increased injury risk in the shoulder and elbow. These motions have been routinely measured with the forearm in neutral rotation (GIRN, GERN, TAMN). GER capacity appears to be especially important. The throwing motion, however, requires forearm pronation as GER occurs to achieve optimal cocking (GERP). No previous studies have evaluated GERP to determine GER capacity or pronated TAM (TAMP) values., Hypothesis: There would be significant differences between GERN and TAMN and between GERP and TAMP., Study Design: Cross-sectional., Level of Evidence: Level 3., Methods: Sixty asymptomatic male Minor League Baseball players (32 pitchers, 28 position players) participated in the study and were tested on the first day of spring training. Passive range of motion measurements were recorded using a long-arm bubble goniometer for GIRN, GERN, and GERP on both arms. TAM was calculated separately as the sum of internal and external rotational measurements under neutral and pronated conditions., Results: Within pitchers and position players, all measurements were statistically reduced for the throwing arm ( P ≤ 0.03) except for GERN of the pitchers. GERP measures were significantly less than GERN for both arms of each group ( P < 0.01): pitchers throwing arm +11.8°/nonthrowing arm +4.8°, position players throwing arm = +8.6°/nonthrowing arm +4.0°., Conclusion: The forearm position of pronation, which appears to be mediated by tightness of the biceps, decreases GER capacity and TAM. GER and TAM should be calculated in neutral and pronated positions, considering that 80% of the players have a demonstrated difference between 8° and 12°., Clinical Relevance: Measurement of GERP more accurately reflects the GER required in throwing, allows better quantification of the motion capacity necessary to withstand the loads in throwing, and may suggest interventions for at risk athletes.

Background: There is a lack of evidence regarding the success of ulnar collateral ligament (UCL) revision reconstruction. Understanding outcomes after UCL revision reconstruction is important in clinical decision making for overhead athletes., Purpose: To evaluate return to play and patient-reported outcomes after UCL revision reconstruction., Study Design: Case series; Level of evidence, 4., Methods: All patients who underwent UCL revision reconstruction, attributed to retear of the ligament or pain, between June 2004 and July 2016 at 2 surgical centers were identified. Charts were reviewed for age, sex, date of primary and revision reconstruction, sport played, level of play, graft type, and complications. Patients were contacted by telephone to determine time to return to play, current level of participation, Conway score, Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow Score, and satisfaction., Results: Of the 65 consecutive baseball players who underwent revision UCL reconstruction, 40 (62%) were contacted at a minimum 22 months after surgery. Of these, 38 (95%) were pitchers and 2 (5%) were position players. Time to return to throwing was 6.2 ± 2.3 months (mean ± SD), and the KJOC score was 74.2 ± 20.7. Based on the Conway score, 50% (20/40) had an excellent result, indicating a return to the previous competition level for at least 1 year, and 30% (12/40) had a good result, indicating a return to a lower level for at least 1 year. For those who were able to return to competition, it took 12.7 ± 3.6 months. In pitchers, 47% (18/38) returned to their previous competition levels for at least 1 year, with a KJOC score of 73.7 ± 21.1. Pitchers were able to return to throwing at 6.3 ± 2.3 months and competition at 12.8 ± 3.7 months., Conclusion: Only half of baseball players undergoing UCL revision reconstruction were able to return to their previous levels of competition. Outcomes for revision reconstructions are not as promising as primary procedures. Baseball players should be cautioned that they may not return to their previous levels of play after a revision reconstruction.

Background: Shoulder injuries from repetitive baseball pitching continue to be a serious, common problem., Purpose: To determine whether passive range of motion of the glenohumeral joint was predictive of shoulder injury or shoulder surgery in professional baseball pitchers., Study Design: Cohort study; Level of evidence, 2., Methods: Passive range of motion of the glenohumeral joint was assessed with a bubble goniometer during spring training for all major and minor league pitchers of a single professional baseball organization over a period of 8 successive seasons (2005-2012). Investigators performed a total of 505 examinations on 296 professional pitchers. Glenohumeral external and internal rotation was assessed with the pitcher supine and the arm abducted to 90° in the scapular plane with the scapula stabilized anteriorly at the coracoid process. Total rotation was defined as the sum of internal and external glenohumeral rotation. Passive shoulder flexion was measured with the pitcher supine and the lateral border of the scapula manually stabilized. After examination, shoulder injuries and injury durations were recorded by each pitcher's respective baseball organization and reported to the league as an injury transaction as each player was placed on the disabled list., Results: Highly significant side-to-side differences were noted within subjects for each range of motion measurement. There were 75 shoulder injuries and 20 surgeries recorded among 51 pitchers, resulting in 5570 total days on the disabled list. Glenohumeral internal rotation deficit, total rotation deficit, and flexion deficit were not significantly related to shoulder injury or surgery. Pitchers with insufficient external rotation (<5° greater external rotation in the throwing shoulder) were 2.2 times more likely to be placed on the disabled list for a shoulder injury (P = .014; 95% CI, 1.2-4.1) and were 4.0 times more likely to require shoulder surgery (P = .009; 95% CI, 1.5-12.6)., Conclusion: Insufficient shoulder external rotation on the throwing side increased the likelihood of shoulder injury and shoulder surgery. Sports medicine clinicians should be aware of these findings and develop a preventive plan that addresses this study's findings to reduce pitchers' risk of shoulder injury and surgery., (© 2015 The Author(s).)

Background: While the high rate of ulnar collateral ligament (UCL) injuries in professional baseball is widely discussed in the media and medical literature, the actual prevalence of UCL reconstruction has not been documented., Hypothesis: The prevalence of UCL reconstruction will be higher among pitchers than nonpitchers, and Major League Baseball (MLB) pitchers will have a higher prevalence than will minor league pitchers., Study Design: Descriptive epidemiology study., Methods: An online questionnaire was distributed to all 30 MLB organizations. Certified athletic trainers from each team administered the questionnaire to all players in the organization, including major league players and 6 levels of minor league players. Demographic data were compared between major and minor league players. Continuous variables (age, years of professional baseball, country of origin, etc) were compared with Student t tests (P < .05). Categorical variables (level, position, etc) were compared using chi-square analysis (P < .05)., Results: A total of 5088 professional baseball players (722 major league and 4366 minor league) participated in the survey. Pitchers represented 53% of all players, and 497 players reported at least 1 UCL reconstruction, demonstrating a prevalence rate of 10% (497 of 5088). Pitchers reported a significantly higher prevalence of UCL reconstruction (16%; 437 of 2706) than nonpitchers (3%; 60 of 2382; P < .001). Among major league pitchers, 25% (96 of 382) had a history of UCL reconstruction, while minor league pitchers showed a 15% (341 of 2324) prevalence (P < .001). Major league pitchers were also significantly older (28.8 ± 3.9 years) than minor league pitchers (22.8 ± 3.0; P < .001). The majority of major leaguers (86%) had their UCL reconstruction as professional pitchers, whereas the majority of minor league pitchers (61%) underwent their UCL reconstruction during high school and college (P < .001). The rates of UCL revision, prior elbow surgery, prior shoulder surgery, and types of UCL graft were similar between the major league and minor league pitchers. No difference in prevalence was shown between pitchers born in the United States versus Latin American countries., Conclusion: Pitchers have a high prevalence of UCL reconstruction in professional baseball, with 25% of major league pitchers and 15% of minor league pitchers having a history of the surgery., (© 2015 The Author(s).)

Background: Injuries to the elbow joint in baseball pitchers appear common. There appears to be a correlation between shoulder range of motion and elbow injuries., Purpose: To prospectively determine whether decreased ROM of the throwing shoulder is correlated with the onset of elbow injuries in professional baseball pitchers., Study Design: Cohort study; Level of evidence, 2., Methods: For 8 consecutive years (2005-2012), passive range of motion of both the throwing and nonthrowing shoulders of all major and minor league pitchers within a single professional baseball organization were measured by using a bubble goniometer during spring training. In total, 505 examinations were conducted on 296 pitchers. Glenohumeral external rotation and internal rotation were assessed in the supine position with the arm at 90° of abduction and in the plane of the scapula. The scapula was stabilized per methods previously established. Total rotation was defined as the sum of external rotation and internal rotation. Passive shoulder flexion was assessed with the subject supine and the scapula stabilized per methods previously established. Elbow injuries and days missed because of elbow injuries were assessed and recorded by the medical staff of the team. Throwing and nonthrowing shoulder measurements were compared by using Student t tests; 1-tailed Fisher exact tests were performed to identify significant associations between shoulder motion and elbow injury. Nominal logistic regression was performed to determine the odds of elbow injury., Results: Significant differences were noted during side-to-side comparisons within subjects. There were 49 elbow injuries and 8 surgeries in 38 players, accounting for a total of 2551 days missed. Neither glenohumeral internal rotation deficit nor external rotation insufficiency was correlated with elbow injuries. Pitchers with deficits of >5° in total rotation in their throwing shoulders had a 2.6 times greater risk for injury. Pitchers with deficit of ≥5° in flexion of the throwing shoulder had a 2.8 times greater risk for injury., Conclusion: Bilateral differences in shoulder total rotation and flexion had a significant effect on the risk for elbow injuries in pitchers. Clinicians need to be aware of these findings and plan preventive programs that address these issues in hopes of reducing elbow injuries., (© 2014 The Author(s).)

Background: An olecranon stress fracture is a rare injury associated with valgus extension overload in baseball players. No long-term outcomes studies have been published documenting the results of surgical fixation of olecranon stress fractures with or without concomitant injuries in baseball players., Hypothesis: Open reduction and internal fixation (ORIF) of an olecranon stress fracture will reliably produce bony union and allow a successful return to the previous level of activity in competitive baseball players., Study Design: Case series; Level of evidence, 4., Methods: Twenty-five patients treated with ORIF for an olecranon stress fracture at least 2 years earlier (range, 2-10.14 years) were retrospectively contacted to complete a telephone survey; 18 of 25 (72%) patients responded. Data were collected to determine the return to play rate, level of arm pain, and overall arm function., Results: All 18 stress fractures went on to successful union; 17 of 18 (94%) athletes returned to baseball at or above their previous level. Average return to play time was 29 weeks. The numeric analog pain score was 0.2 at rest and 0.3 when throwing at the time of follow-up, at an average 6.2 years (range, 2.0-10.14 years) after surgery. The average score at follow-up on the disabilities of the arm, shoulder and hand outcome measure-shortened version (QuickDASH) was 4.1 (range, 0-27.3). Ten (56%) patients required 13 additional future surgeries on their throwing arm; 7 surgeries in 6 (33%) patients were not related to the index surgery. Six of 18 (33%) patients underwent hardware removal, with 2 (11%) for infection., Conclusion: Open reduction and internal fixation of olecranon stress fractures in competitive baseball players has a high rate of success in returning players to or above their former level of play and allows for good elbow function at an average of 6.2 years postoperatively. However, these patients are at high risk for additional future surgeries on their throwing arm.

Throwing velocity is an important baseball performance variable for baseball pitchers, because greater throwing velocity results in less time for hitters to make a decision to swing. Throwing velocity is also an important baseball performance variable for position players, because greater throwing velocity results in decreased time for a runner to advance to the next base. This study compared the effects of 3 baseball-specific 6-week training programs on maximum throwing velocity. Sixty-eight high school baseball players 14-17 years of age were randomly and equally divided into 3 training groups and a nontraining control group. The 3 training groups were the Throwers Ten (TT), Keiser Pneumatic (KP), and Plyometric (PLY). Each training group trained 3 d·wk(-1) for 6 weeks, which comprised approximately 5-10 minutes for warm-up, 45 minutes of resistance training, and 5-10 for cool-down. Throwing velocity was assessed before (pretest) and just after (posttest) the 6-week training program for all the subjects. A 2-factor repeated measures analysis of variance with post hoc paired t-tests was used to assess throwing velocity differences (p < 0.05). Compared with pretest throwing velocity values, posttest throwing velocity values were significantly greater in the TT group (1.7% increase), the KP group (1.2% increase), and the PLY group (2.0% increase) but not significantly different in the control group. These results demonstrate that all 3 training programs were effective in increasing throwing velocity in high school baseball players, but the results of this study did not demonstrate that 1 resistance training program was more effective than another resistance training program in increasing throwing velocity.

Background: Repetitive overhead throwing motion causes motion adaptations at the glenohumeral joint that cause injury, decrease performance, and affect throwing mechanics. It is essential to define the typical range of motion (ROM) exhibited at the glenohumeral joint in the overhead thrower., Questions/purposes: We (1) assessed the glenohumeral joint passive range of motion (PROM) characteristics in professional baseball pitchers; and (2) applied these findings clinically in a treatment program to restore normal PROM and assist in injury prevention., Methods: From 2005 to 2010, we evaluated 369 professional baseball pitchers to assess ROM parameters, including bilateral passive shoulder external rotation (ER) at 45° of abduction, external and internal rotation (IR) at 90° abduction while in the scapular plane, and supine horizontal adduction., Results: The mean ER was greater for the throwing and nonthrowing shoulders at 45° of abduction, 102° and 98°, respectively. The throwing shoulder ER at 90° of abduction was 132° compared with 127° on the nonthrowing shoulder. Also, the pitcher's dominant IR PROM was 52° compared with 63° on the nondominant side. We found no statistically significant differences in total rotational motion between the sides., Conclusions: Although we found side-to-side differences for rotational ROM and horizontal adduction, the total rotational ROM was similar., Clinical Relevance: The clinician can use these PROM values, assessment techniques, and treatment guidelines to accurately examine and develop a treatment program for the overhead-throwing athlete.

Study Design: Controlled laboratory study., Objectives: To test for kinematic and kinetic differences between baseball pitching from a mound and long-toss on flat ground., Background: Long-toss throws from flat ground are commonly used by baseball pitchers for rehabilitation, conditioning, and training. However, there is controversy over the biomechanics and functionality of such throws., Methods: Seventeen healthy, college baseball pitchers pitched fastballs 18.4 m from a mound to a strike zone, and threw 37 m, 55 m, and maximum distance from flat ground. For the 37-m and 55-m throws, participants were instructed to throw "hard, on a horizontal line." For the maximum-distance throw, no constraint on trajectory was given. Kinematics and kinetics were measured with a 3-dimensional, automated motion analysis system. Repeated-measures analyses of variance, with post hoc paired t tests, were used to compare the 4 throw types within pitchers., Results: At foot contact, the participant's shoulder line was nearly horizontal when pitching from a mound and became progressively more inclined as throwing distance increased. At arm cocking, the greatest amount of shoulder external rotation (mean ± SD, 180° ± 11°), elbow flexion (109° ± 10°), shoulder internal rotation torque (101 ± 17 Nm), and elbow varus torque (100 ± 18 Nm) were measured during the maximum-distance throws. Elbow extension velocity was also greatest for the maximum-distance throws (2573°/s ± 203°/s). Forward trunk tilt at the instant of ball release decreased as throwing distance increased., Conclusion: Hard, horizontal, flat-ground throws have biomechanical patterns similar to those of pitching and are, therefore, reasonable exercises for pitchers. However, maximum-distance throws produce increased torques and changes in kinematics. Caution is, therefore, advised in the use of these throws for rehabilitation and training.

Background: Glenohumeral internal rotation deficit (GIRD) indicates a 20° or greater loss of internal rotation of the throwing shoulder compared with the nondominant shoulder., Purpose: To determine whether GIRD and a deficit in total rotational motion (external rotation + internal rotation) compared with the nonthrowing shoulder correlate with shoulder injuries in professional baseball pitchers., Study Design: Case series; Level of evidence, 4., Methods: Over 3 competitive seasons (2005 to 2007), passive range of motion measurements were evaluated on the dominant and nondominant shoulders for 170 pitcher-seasons. This included 122 professional pitchers during the 3 seasons of data collection, in which some pitchers were measured during multiple seasons. Ranges of motion were measured with a bubble goniometer during the preseason, by the same examiner each year. External and internal rotation of the glenohumeral joint was assessed with the participant supine and the arm abducted 90° in the plane of the scapula, with the scapula stabilized anteriorly at the coracoid process. The reproducibility of the test methods had an intraclass correlation coefficient of .81. Days in which the player was unable to participate because of injury or surgery were recorded during the season by the medical staff of the team and defined as an injury., Results: Pitchers with GIRD (n = 40) were nearly twice as likely to be injured as those without but without statistical significance (P = .17). Pitchers with total rotational motion deficit greater than 5° had a higher rate of injury. Minor league pitchers were more likely than major league pitchers to be injured. However, when players were injured, major league pitchers missed a significantly greater number of games than minor league pitchers., Conclusion: Compared with pitchers without GIRD, pitchers with GIRD appear to be at a higher risk for injury and shoulder surgery.

Background: Pelvis and trunk motions during baseball pitching are associated with ball velocity. Thus, limits in hip flexibility may adversely affect pitching biomechanics and the ability to generate ball velocity., Hypotheses: Professional baseball pitchers will have less passive range of motion in the nondominant hip and the measured ranges of motion of both the nondominant and dominant hips will correlate with biomechanical parameters of the lower extremity among professional pitchers., Study Design: Cross-sectional study; Level of evidence, 3., Methods: Nineteen healthy professional baseball pitchers volunteered for testing. Fluid goniometry was used to measure passive range of motion of adduction (ADD), abduction (ABD), internal rotation, external rotation, total arc of rotation, and total arc of ADD + ABD. Pitching biomechanical data were collected using an automated 3-dimensional motion analysis system while participants threw fastballs., Results: Pitchers possessed significantly less passive range of motion in the nondominant hip when compared with the dominant hip for all ranges. Total arc of rotation of the nondominant hip correlated with ball velocity (r = .50). Total arc of ADD + ABD in the nondominant hip and ABD in the nondominant hip were correlated with stride length (r = -.72 and .70, respectively). Dominant hip ABD (r = .63), total arc of rotation in the nondominant hip (r = -.45), and total arc of ADD + ABD of the dominant hip (r = .44) were correlated with trunk separation. Total arc of ADD + ABD of the nondominant hip (r = -.52) and total arc of rotation of the dominant hip (r = -.44) were correlated with pelvic orientation., Conclusion: Passive range of motion is smaller in the nondominant hip than the dominant hip among professional pitchers. The measured disparity between the hips is significantly correlated with various pitching biomechanical parameters of the trunk and pelvis. Future research is required to investigate a causal relationship between less hip passive range of motion and both ball velocity and pitching biomechanics.

Background: The anterior bundle of the ulnar collateral ligament (UCL) is the primary anatomical structure providing elbow stability in overhead sports, particularly baseball. Injury to the UCL in overhead athletes often leads to symptomatic valgus instability that requires surgical treatment., Hypothesis: Ulnar collateral ligament reconstruction with a free tendon graft, known as Tommy John surgery, will allow return to the same competitive level of sports participation in the majority of athletes., Study Design: Case series; Level of evidence, 4., Methods: Ulnar collateral reconstruction (1266) or repair (15) was performed in 1281 patients over a 19-year period (1988-2006) using a modification of the Jobe technique. Data were collected prospectively and patients were surveyed retrospectively with a telephone questionnaire to determine outcomes and return to performance at a minimum of 2 years after surgery., Results: Nine hundred forty-two patients were available for a minimum 2-year follow-up (average, 38.4 months; range, 24-130 months). Seven hundred forty-three patients (79%) were contacted for follow-up evaluation and/or completed a questionnaire at an average of 37 months postoperatively. Six hundred seventeen patients (83%) returned to the previous level of competition or higher, including 610 (83%) after reconstruction. The average time from surgery to the initiation of throwing was 4.4 months (range, 2.8-12 months) and the average time to full competition was 11.6 months (range, 3-72 months) after reconstruction. Complications occurred in 148 patients (20%), including 16% considered minor and 4% considered major., Conclusion: Ulnar collateral ligament reconstruction with subcutaneous ulnar nerve transposition was found to be effective in correcting valgus elbow instability in the overhead athlete and allowed most athletes (83%) to return to previous or higher level of competition in less than 1 year.

Objective: The objective of this article is to report and describe the clinical and imaging features of an avulsion fracture of the medial epicondyle after ulnar collateral ligament (UCL) reconstruction., Conclusion: Avulsion fracture of the medial epicondyle is a rare complication of UCL reconstruction with distinct radiographic and MRI findings.

Background: The overhead throwing athlete has unique range of motion characteristics of the shoulder and elbow. Numerous theories exist to explain these characteristics; however, the precise cause is not known. Although it is accepted that range of motion is altered, the acute effect of baseball pitching on shoulder and elbow range of motion has not been established., Hypothesis: There will be a reduction in passive range of motion immediately after baseball pitching., Study Design: Controlled laboratory study., Methods: Sixty-seven asymptomatic male professional baseball pitchers participated in the study. Passive range of motion measurements were recorded using a customized bubble goniometer for shoulder external rotation, shoulder internal rotation, total shoulder rotational motion, elbow flexion, and elbow extension on the dominant and nondominant arms. Testing was performed on the first day of spring training. Measurements were taken before, immediately after, and 24 hours after pitching., Results: A significant decrease in shoulder internal rotation (-9.5 degrees), total motion (-10.7 degrees), and elbow extension (-3.2 degrees) occurred immediately after baseball pitching in the dominant shoulder (P<.001). These changes continued to exist 24 hours after pitching. No differences were noted on the nondominant side., Conclusion: Passive range of motion is significantly decreased immediately after baseball pitching. This decrease in range of motion continues to be present 24 hours after throwing. High levels of eccentric muscle activity have previously been observed in the shoulder external rotators and elbow flexors during pitching. These eccentric muscle contractions may contribute to acute musculotendinous adaptations and altered range of motion. The results of this study may suggest a newly defined mechanism to range of motion adaptations in the overhead throwing athlete resulting from acute musculoskeletal adaptations, in addition to potential osseous and capsular adaptations.

Purpose: This study was conducted to perform kinematic measures in a group of asymptomatic professional baseball pitchers to determine side-to-side differences in passive glenohumeral range of motion (ROM) and stiffness. We hypothesized that the throwing shoulder in asymptomatic pitchers would display greater passive glenohumeral stiffness than the contralateral nonthrowing shoulder., Methods: Thirty-four professional baseball pitchers had bilateral assessments for passive glenohumeral ROM and stiffness during a single test session. ROM and stiffness measures were obtained objectively using standard goniometry and instrumented stress arthrometry, respectively., Results: The throwing shoulder had significantly less (-8.5 degrees) internal rotation and significantly more external rotation (5.1 degrees) than the nonthrowing shoulder (P < 0.01). Passive joint stiffness was not significantly different between the throwing and nonthrowing shoulder, and anterior joint stiffness was significantly greater than posterior joint stiffness for both shoulders (P < 0.05)., Conclusions: The repetitive stress of long-term throwing creates altered glenohumeral rotational patterns in the throwing shoulder of the professional baseball pitcher without compromising the joint's passive restraining quality.

Background: Altered mobility patterns in the throwing shoulders of professional baseball pitchers have been reported. Most published reports examining glenohumeral laxity have not used an objective testing device., Objective: Quantify and compare glenohumeral translation and rotational range of motion between the throwing and non-throwing shoulders in professional baseball pitchers., Study Design: Descriptive laboratory study., Methods: Force-displacement and range of motion measures were performed bilaterally on 43 asymptomatic professional baseball pitchers. Ultrasound imaging was used to measure glenohumeral translations under stressed and unstressed conditions., Results: No significant difference in translation was found between the throwing and nonthrowing shoulders. For both shoulders, posterior translation (5.38 +/- 2.7 mm) was significantly greater (P < .001) than was anterior translation (2.81 +/- 1.6 mm). External rotation in the throwing shoulder was significantly greater than that in the nonthrowing shoulder (P < .001), whereas internal rotation in the throwing shoulder was significantly less than that in the nonthrowing shoulder (P < .001). The total arc of rotation for the throwing shoulder was not significantly different than that for the nonthrowing shoulder, and correlation coefficients were poor between rotational and translational range of motion in the throwing shoulder, ranging from r = 0.232 to 0.209 between variables., Conclusion: No significant difference in glenohumeral translation exists between the throwing and nonthrowing shoulders in asymptomatic professional baseball pitchers, posterior translation is significantly greater than anterior translation in the throwing shoulders of professional baseball pitchers, and glenohumeral translation is not related to rotational range of motion in the throwing shoulders of professional baseball pitchers., Clinical Relevance: Altered mobility patterns in asymptomatic professional baseball pitchers may be due to factors other than capsular adaptive changes.

Background: Previous studies have documented changes in musculature, bony anatomy, and glenohumeral rotation in the dominant shoulder of baseball players., Hypothesis: In a group of asymptomatic college baseball players the total range of motion in the dominant and nondominant shoulders will be similar. Any measured increase in external rotation and decrease in internal rotation occurring between the two sides will be consistent and directly correlate with an increased angle of humeral retroversion in the dominant extremity., Study Design: Descriptive anatomic study., Methods: Fifty-four asymptomatic college baseball players were examined. Standard measurements of glenohumeral range of motion were made and humeral retroversion was determined radiologically., Results: Total rotational motion, measured at 90 degrees of glenohumeral abduction, was 159.5 degrees for the dominant shoulders and 157.8 degrees for the nondominant shoulders. Mean differences in external and internal rotation in the dominant versus nondominant extremities were 9.7 degrees and 8.2 degrees, respectively. Humeral retroversion measured 36.6 degrees +/- 9.8 degrees in the dominant and 26 degrees +/- 9.4 degrees in the nondominant extremity. The mean difference in retroversion correlated significantly by Pearson's product moment with the difference in external (P = 0.001) and internal (P = 0.003) rotation measurements., Conclusions: There is a pattern of increased external rotation and decreased internal rotation in the dominant extremity that significantly correlates with an increase in humeral retroversion. The loss of internal rotation and gains in external rotation may be more strongly related to adaptive changes in proximal humeral anatomy than to changes in the soft tissues.

The throwing shoulder in pitchers frequently exhibits a paradox of glenohumeral joint motion, in which excessive external rotation is present at the expense of decreased internal rotation. The object of this study was to determine the role of humeral head retroversion in relation to increased glenohumeral external rotation. Glenohumeral joint range of motion and laxity along with humeral head and glenoid version of the dominant versus nondominant shoulders were studied in 25 professional pitchers and 25 nonthrowing subjects. Each subject underwent a computed tomography scan to determine bilateral humeral head and glenoid version. The throwing group demonstrated a significant increase in the dominant shoulder versus the nondominant shoulder in humeral head retroversion, glenoid retroversion, external rotation at 90 degrees, and external rotation in the scapular plane. Internal rotation was decreased in the dominant shoulder. Total range of motion, anterior glenohumeral laxity, and posterior glenohumeral laxity were found to be equal bilaterally. The nonthrowing group demonstrated no significant difference in humeral head retroversion, glenoid retroversion, external rotation at 90 degrees or external rotation in the scapular plane between shoulders, and no difference in internal rotation at 90 degrees, total motion, or laxity. A comparison of the dominant shoulders of the two groups indicated that both external rotation at 90 degrees and humeral head retroversion were significantly greater in the throwing group.

Background Interval throwing programs (ITP) have been used for decades to enable baseball pitchers to return to competition after injury or surgery by gradually applying load to the throwing arm. Past programs have been based on personal experience; however, advances in our understanding of the biomechanics and workloads of throwing allow for a more modern data-based program to be developed. Hypothesis/Purpose To 1) develop a updated ITP for rehabilitation of modern baseball pitchers based upon biomechanical and throwing workload data, and 2) compare the updated program with a past program to determine differences in chronic workload and acute:chronic workload ratios (ACWR). Study Design Cross-sectional study Methods Workloads (i.e. daily, acute, chronic, and ACWR) for the original ITP were built from the prescribed throwing schedule. Elbow varus torque per throw was calculated based upon a relationship between elbow varus torque and throwing distance. Throw counts, daily/ chronic/acute workloads, and ACWR were calculated and plotted over time. A new ITP was built to model current pitcher's throwing schedules and gradually increased ACWR over time. Results The original ITP had a throwing schedule of 136 days, final chronic workload 15.0, and the ACWR above or below the "safe" range (i.e. 0.7 - 1.3) for 18% of the program with a peak of 1.61. The updated ITP was built to consist of a 217-day schedule, final chronic workload of 10.8, and deviated from the safe range for 9% of the program, with a peak of 1.33. Conclusion The newly created ITP is more familiar to modern baseball pitchers while exhibiting a more gradual buildup of chronic workload than traditional ITP programs. This ITP may be used to return baseball pitchers back to competition as safely and efficiently as possible, and potentially with less risk of setbacks or reinjury. The ITP may be used following common injuries or surgeries to the throwing shoulder and elbow, such as Tommy John surgery, while also serving as a basis for future development of shorter duration ITPs. Level of Evidence 2c [ABSTRACT FROM AUTHOR]

Background Interval throwing programs are used in rehabilitation of throwing injuries, especially ulnar collateral ligament injuries. Athletes who are rehabilitating begin by throwing on flat ground progressing through increasing distances, number of throws, and intensity of throwing. If the athlete is a baseball pitcher, the flat-ground throwing phase is followed by pitching on a mound at progressively increased effort. The goal is to build back arm strength and capacity with an emphasis on proper mechanics. Purpose To determine whether interval throwing progressively builds joint kinetics (specifically, elbow varus torque) to the level required during full-effort baseball pitching. A secondary purpose was to examine the kinematics produced during interval throwing compared to those seen during baseball pitching. Study Design Systematic Review Methods Following PRISMA guidelines, PubMed, Embase, Web of Science, SPORTDiscus, and Google Scholar were systematically searched for biomechanical studies of flat-ground throwing and partial-effort pitching in baseball between 1987 and 2023. Studies that reported the biomechanics of either flat-ground throwing, or partial-effort pitching were included in this review. The AXIS tool was used to assess study quality. Results Thirteen articles met the inclusion criteria. Ten studies were determined to be of moderate quality, while three studies were deemed high quality. Elbow varus torque during partial-effort pitching was less than during full-effort pitching. Elbow varus torque for most flat-ground throws did not exceed full-effort pitching torque. While most studies showed increased elbow varus torque with increased flat-ground throwing distance, the distance at which elbow varus torque matched or exceeded full-effort pitching elbow varus torque was not consistent. As flat-ground throwing distance increased, shoulder external rotation angle and shoulder internal rotation velocity increased. Arm slot (forearm angle above horizontal) decreased as flat-ground throwing distance increased. For varied effort pitching, shoulder external rotation angle, shoulder internal rotation velocity, elbow extension velocity, and ball velocity increased as effort increased. While the front knee extended slightly from foot contact to ball release in full-effort pitching, the front knee flexed slightly during partial-effort pitching. Conclusions An interval throwing program progressively builds elbow varus torque up to levels produced in full-effort baseball pitching. While differences exist between interval throwing kinematics and pitching kinematics, the patterns are similar in general. [ABSTRACT FROM AUTHOR]

The overhead throwing motion is an extremely stressful athletic movement. The high velocity and repetitive nature of this activity places immense pressure on the entire body, which can frequently result in injury to the throwing arm. Extensive literature exists with regards to the management of these injuries in the collegiate and professional level athlete; and it is well understood that a multiphasic approach is required to return an individual to prior level of play. However, there is a gap in the literature which fails to address the management of youth individuals. This article presents a new and innovative approach to the rehabilitation, training and management of the youth overhead throwing athlete, The Youth Throwers Ten Exercise Program. This program addresses principles of: coactivation, coordination, dynamic stabilization, neuromuscular control, proprioception, muscle strength, endurance and scapular rhythm all of which are vital for successful performance. This exercise series utilizes bodyweight and Theraband exercises that cater to the unique characteristics of the youth athlete making it a safe way to prepare for the demands of overhead throwing activities. [ABSTRACT FROM AUTHOR]

Injuries to the elbow in athletes who play overhead sports, especially in baseball pitchers, continue to increase in frequency. The anterior band of the ulnar collateral ligament (UCL), the primary restraint to valgus stress, is commonly injured from throwing. Historically, such injuries have been treated with surgical reconstruction techniques, using a tendon autograft. A recently developed UCL repair procedure with an internal brace, utilizing collagen tape, is gaining popularity. The primary goal of this surgery is to enhance elbow joint stability while the ligament is healing and to allow earlier return to sport after UCL reconstruction. The rehabilitation program following UCL repair with internal brace progresses through a different time frame than after UCL reconstruction. The purpose of this commentary, based on our experience with more than 350 cases, including 79 patients with at least a 1-year postsurgical follow-up, was to describe and provide the rationale for the rehabilitation process following UCL repair with internal brace [ABSTRACT FROM AUTHOR]

The repetitive overhead motion involved in throwing is responsible for unique and sport-specific patterns of injury to the shoulder joint. Specific strengthening and flexibility plays a vital role in the ultimate function and injury prevention in the overhead-throwing athlete. The clinician must achieve a delicate balance between mobility and stability, which often presents as a significant challenge. Most shoulder injuries in the overhead thrower can be successfully treated nonoperatively to allow the athlete to return to competition. A well-structured, in-season strengthening program that is designed to maintain the athlete's strength, power, and endurance while not inhibiting with the athlete's ability to compete on a regular basis is critical. [ABSTRACT FROM AUTHOR]

The overhead throwing athlete is an extremely challenging patient in sports medicine. The repetitive microtraumatic stresses imposed on the athlete’s shoulder joint complex during the throwing motion constantly place the athlete at risk for injury. Treatment of the overhead athlete requires the understanding of several principles based on the unique physical characteristics of the overhead athlete and the demands endured during the act of throwing. These principles are described and incorporated in a multiphase progressive rehabilitation program designed to prevent injuries and rehabilitate the injured athlete, both nonoperatively and postoperatively. [ABSTRACT FROM PUBLISHER]

Injuries to the ulnar collateral ligament (UCL) in throwing athletes frequently occurs from the repetitive valgus loading of the elbow during the throwing motion, which often results in surgical reconstruction of the UCL requiring a structured postoperative rehabilitation program. Several methods are currently used and recommended for UCL reconstruction using autogenous grafts in an attempt to reproduce the stabilizing function of the native UCL. Rehabilitation following surgical reconstruction of the UCL begins with range of motion and initial protection of the surgical reconstruction, along with resistive exercise for the entire upper extremity kinetic chain. Progressions for resistive exercise are followed that attempt to fully restore strength and local muscular endurance in the rotator cuff and scapular stabilizers, in addition to the distal upper extremity musculature, to allow for a return to throwing and overhead functional activities. Rehabilitation following UCL reconstruction has produced favorable outcomes, allowing for a return to throwing in competitive environments. [ABSTRACT FROM PUBLISHER]

The article presents an overview of shoulder injuries that are seen in athletes who frequently perform overhead throwing motions. A discussion of the shoulder dynamics that are involved in performing overhand throwing movements is presented. Effective treatment modalities which are used with overhand throwing motion injuries are examined.