Injuries In Baseball Players Research Articles

Microscopic Magnetic Resonance Imaging Comparing Asymptomatic and Symptomatic Ulnar Collateral Ligament Injuries in Baseball Players.

The relationship between abnormalities of the ulnar collateral ligament (UCL) on magnetic resonance imaging (MRI) and elbow symptoms in baseball players remains unclear. This study aimed to compare findings of the UCL on microscopic MRI between asymptomatic and symptomatic elbows in baseball players. We hypothesized that the MRI grade of UCL injuries would exhibit no correlation with medial elbow symptoms in baseball players. Cross-sectional study; Level of evidence, 3. The study participants were skeletally mature baseball players who underwent high-resolution microscopic MRI of the medial elbow including for medical checkups. Elbows with previous surgical treatment or traumatic UCL injuries were excluded. The patients were divided into symptomatic and asymptomatic groups. The UCL appearance on microscopic MRI was categorized into 4 grades and compared between the groups. Abnormal findings in the medial elbow including bony fragments at the medial epicondyle, osteophytes or bony fragments in the sublime tubercle, and bone marrow edema (BME) in the sublime tubercle were also evaluated. A total of 426 baseball players (426 elbows) with a mean age of 20 years (range, 14-41 years) were included. The asymptomatic and symptomatic groups included 158 and 268 elbows, respectively. In the asymptomatic group, based on MRI grading of the UCL, 46 (29%) elbows were rated as grade I, 64 (41%) as grade II, 40 (25%) as grade III, and 8 (5%) as grade IV. In the symptomatic group, 75 (28%) elbows were rated as grade I, 118 (44%) as grade II, 61 (23%) as grade III, and 14 (5%) as grade IV. There was no significant difference in the MRI grades between the groups (P = .9). BME in the sublime tubercle was more frequently seen in the symptomatic group than in the asymptomatic group (P < .001). There was no difference in MRI grades of the UCL between symptomatic and asymptomatic elbows in baseball players; approximately 30% of elbows demonstrated high-grade UCL injuries in both groups. BME in the sublime tubercle was more frequently seen in symptomatic elbows than in asymptomatic elbows. BME in the sublime tubercle was a better indicator of symptoms than was MRI grading of the UCL.

Psychological Impact and Posttraumatic Stress Disorder Symptomatology After Ulnar Collateral Ligament Injuries in Baseball Players.

Significant psychological impact and prevalence of posttraumatic stress disorder (PTSD) have been well documented in patients sustaining anterior cruciate ligament injury. To examine PTSD symptomatology in baseball players after sustaining elbow ulnar collateral ligament (UCL) injury. Cross-sectional study; Level of evidence, 3. Male baseball players of various competition levels (high school through Minor League Baseball [MiLB]) who underwent surgery for a UCL injury between April 2019 and June 2022 participated in the study. Before surgery, patients completed the Impact of Event Scale-Revised (IES-R) to assess PTSD symptomatology. Subgroup analysis was conducted according to level of play and player position. A total of 104 male baseball players with a mean age of 19.4 years (range, 15-29 years) were included in the study; 32 players (30.8%) were in high school, 65 (62.5%) were in college, and 7 (6.7%) were in MiLB. There were 64 (61.5%) pitchers, 18 (17.3%) position players, and 22 (21.2%) 2-way players (both pitching and playing on the field). A total of 30 (28.8%) patients scored high enough on the IES-R to support PTSD as a probable diagnosis, and another 22 patients (21.2%) scored high enough to support PTSD as a clinical concern. Nineteen patients (18.3%) had potentially severe PTSD. Only 4 players (3.8%) were completely asymptomatic. Subgroup analysis revealed college players as significantly more symptomatic than high school players (P = .02), and 2-way players were found to be significantly less susceptible to developing symptoms of PTSD compared with pitchers (P = .04). Nearly 30% of baseball players who sustained a UCL injury qualified for a probable diagnosis of PTSD based on the IES-R. Pitchers and college athletes were at increased risk for PTSD after UCL injury compared with 2-way players and high school athletes, respectively.

Epidemiology of Knee Injuries in Baseball Players from the State of São Paulo.

Objective This study aimed to identify the main knee complaints and injuries associated with baseball and their prevalence in the state of São Paulo, Brazil. Methods This epidemiological study analyzed data from an online questionnaire sent to baseball athletes from the state of São Paulo, Brazil, from 2019 to 2022. Results Ninety-eight athletes participated in the study. Their average age was 24.3 years, and 85.72% of the subjects were men. The most prevalent ethnicities were yellow (50%) and white (42.86%). Most athletes had incomplete or complete higher education (75.5%). Most (88.77%) have been training for over 1 year, and 40.82% played in more than 1 position. More than half also practiced another sport. Most (66.32%) athletes present knee complaints or symptoms, and 37.75% had suffered a knee injury playing baseball, with several mechanisms (contact with the ground, contact with another player, or no contact). More than half (59.45%) of the athletes required time away from baseball due to complaints, symptoms, or injuries. Conclusion Among the athletes interviewed, 66.32% had a knee complaint, and 37.75% had already had a knee injury, especially meniscal and ligament injuries. The injury rate was highest in the first year of practice.

Management of ulnar collateral ligament injury in baseball athletes: An online survey in Japanese surgeons

BackgroundThe management of ulnar collateral ligament (UCL) injuries widely varies among surgeons. Although various treatment options have been proposed including surgical and conservative treatments, no golden standard treatment strategy has been established of yet. The American survey reported an overall experienced and well-trained cohort of surgeons often reached consensus opinions on how to approach UCL injury. However, the consensus among Japanese surgeons on the treatment of UCL injuries remains unclear. The purpose of this study was to survey current trends among Japanese orthopaedic surgeons in the treatment of UCL injuries in baseball players. MethodsAn online survey was distributed to the active members of the Japanese doctor's network for baseball injury prevention, which was formed by partial members of the medical committee in the Japan Baseball Council. The survey was composed of three sections: demographics of the surveyees, preferred operative and nonoperative management of UCL injuries, and five fictional clinical case scenarios of baseball players with a UCL injury. ResultsThe 131 e-mailed invitations to society members yielded 78 completed online surveys with a participation rate of 60%. Sixty-four respondents (82%) reported >15 years of clinical experience. Sixty-five respondents (83%) performed ≤5 UCL reconstructions per year. As nonsurgical management of UCL injuries, seventy-four surgeons (95%) preferred physiotherapy followed by intraarticular injection (46%). For surgical management, seventy-three surgeons (93%) preferred UCL reconstruction. Of the five case scenarios, a consensus was reached in three cases: to perform surgery on the patient with full-thickness UCL tear. When operative management was the preferred option, a consensus was reached to perform UCL reconstruction. ConclusionJapanese doctors involved in the treatment of baseball injuries reached a consensus to indicate high-level athletes with a full-thickness UCL tear for surgery. When operative management was the preferred option, a consensus was reached to perform UCL reconstruction. These results may contribute to the decision-making for managing UCL injuries.

Lens exposure during computed tomography for elbow injuries in baseball players: a phantom study

Lens exposure during computed tomography for elbow injuries in baseball players: a phantom study

The impact of resistance-based training programs on throwing performance and throwing-related injuries in baseball players: A systematic review

The aim of this systematic review is to assess the effects of structured resistance training programs on the throwing performance and injury risk of baseball players, irrespective of their age or sex. The literature search was carried out on 18/10/2023, utilizing databases that include PubMed, Scopus, and the Web of Science. Our inclusion criteria encompassed research involving baseball players of all ages and sex who had undergone resistance-based training interventions. For comparison, we considered active control groups, irrespective of their exposure to additional training programs. The outcomes under investigation were related to throwing performance (i.e., throwing velocity and accuracy) and injuries associated with throwing. In our review, we exclusively included studies with a two- or multi-arm design. We evaluated the risk of bias using the PEDro scale. Out of the initial pool of 509 studies, we carefully examined 27 full-text articles and ultimately selected and analyzed 16 studies for inclusion in our review. Out of the 12 studies that compared and presented the inferential statistics for the post-training effects of the experimental versus control groups, it was observed that 8 of these studies demonstrated a significantly more favorable impact of the experimental group on enhancing throwing velocity when compared to the control group. Out of the three studies that compared the experimental and control groups in terms of throwing accuracy, only one study showed a significant improvement in the experimental group compared to the control group after the intervention. In conclusion, this systematic review indicates that resistance-based training interventions appear to be effective in enhancing throwing velocity. However, the evidence regarding the efficacy of these interventions in improving throwing accuracy is less robust. It is worth noting that while some experimental conditions may lead to an increase in injury rates, there is limited data available on this aspect, with only a few studies reporting on this variable.

Shoulder kinetic during pitching in baseball players with scapular dyskinesis

IntroductionShoulder injuries in baseball players cause excessive shoulder load during pitching and scapular dyskinesis (SD). However, the characteristics of pitching kinetics in the shoulder joint with SD are unclear. This study aimed to investigate the effect of SD on pitching kinetics in the shoulder joint of baseball players. MethodSeventy-two college and independent league baseball players participated in the study. The pitching motion was measured using an 18–camera motion-capture system. SD was classified into four types (I–IV) using the scapular dyskinesis test (SDT). The pitching kinetics data were analyzed. ResultsThe agreement of SD in this study was 56/72 (77.8%). SD were classified into 31 abnormal group (type I–Ⅲ) and 25 control group (type Ⅳ). Three participants with measurement failure during the pitching motion analysis were excluded from the analysis. The abnormal group showed a larger maximum value of the glenohumeral normalized anterior joint force than the control group. ConclusionsThese results suggest that an increase in GH anterior force during pitching causes an excessive increase in external rotation of the GH with an insufficient posterior tilt of the scapula with SD. Therefore, baseball pitching with SD may involve shoulder injuries owing to excessive shoulder load during pitching.

Swinging injuries in competitive baseball players.

Injuries are common in competitive baseball players and can occur in all facets of the game. The majority of the existing literature on injuries in baseball players has focused on injuries secondary to the overhead throw with very little attention given to injuries sustained while batting. The baseball swing is a complex, often violent, motion that predisposes batters to a variety of injuries affecting the spine, trunk, pelvis, and extremities. Knowledge of injury patterns that commonly occur during the baseball swing and radiologic findings important to the treating physician can help radiologists provide accurate imaging interpretations that appropriately guide patient management.

Common Hand Injuries in the Baseball Player.

The list of potential hand and wrist injuries among baseball players is numerous and includes fractures, dislocations, strains, and sprains. The purpose of this review, however, is to highlight injuries to the hand and wrist which are either particularly common or unique to professional baseball players with an emphasis on diagnostic pearls and treatment principles. For many baseball-related hand and wrist injuries, descriptions of the pathophysiology, diagnosis, and treatment options are based on single institution case series. With the implementation of Major League Baseball's Health and Injury Tracking System, our understanding of the epidemiology of these injuries in professional baseball players has greatly improved. The most common injury requiring operative treatment is a hook of hamate fracture, and recent evidence increasingly supports fracture fragment excision for early pain-free return to sport. Fractures of the proximal phalanges of fingers, thumb phalangeal fractures, and UCL injuries are the most common indication for surgery of the digits. A4 pulley ruptures in pitchers and repetitive trauma to the vasculature of the palm and digits are relatively unique to professional baseball players and are frequently able to be managed non-operatively. While injuries to the hand and wrist are common, the median number of days missed due to such an injury was only 4 days among professional baseball players. Statements and Declarations" for inclusion in the published paper. Please note that submissions that do not include relevant declarations will be returned as incomplete.

Knowledge and Perceptions of Ulnar Collateral Ligament Injuries in Baseball Players: A Survey of NCAA Head Baseball Coaches.

There is growing concern among sports medicine professionals regarding the increasing prevalence of ulnar collateral ligament (UCL) surgery in baseball players. At this time, it is unclear whether collegiate head baseball coaches possess adequate knowledge of UCL injuries. The purpose of this study was to assess the knowledge and perceptions of UCL injury among National Collegiate Athletic Association (NCAA) head baseball coaches. It was hypothesized that NCAA head baseball coaches would demonstrate misconceptions and knowledge disparities regarding UCL injury. Cross-sectional study. An online 35-question survey was designed to assess NCAA head baseball coaches' knowledge of UCL injury. The survey included questions related to participant characteristics, UCL injury, biometric performance and pitching variables, throwing fatigue, surgical variables/performance outcomes, and collegiate athlete recruitment. A total of 788 NCAA head baseball coaches were asked to participate. Responses were analyzed and reported using descriptive statistics where appropriate. Statistical comparisons and contrasts were made using chi-square and Fisher exact tests. A total of 103 NCAA head baseball coaches participated in the survey, representing a 13.1% response rate. Only 31% of respondents could correctly identify all UCL injury symptoms, and 93% recommended <8 weeks off from overhead throwing during the off-season. Previous elbow injury observation was associated with UCL symptom identification (χ2 = 10.614; P = .005). Regular access to an athletic trainer (P = .015) and regular access to a strength and conditioning coach (P = .004) were both associated with NCAA division status, with Division I programs having the most access. Neither sports medicine physician (P = .656) nor athletic trainer (P = .611) access was associated with the geographic location of the baseball program; however, strength and conditioning coach access was associated with geographic location (χ2 = 6.696; P = .010). This study demonstrates that limited UCL injury knowledge and various misconceptions exist among NCAA baseball head coaches. The majority of responding coaches recommended an amount of time off from overhead throwing during the off-season that may be inadequate and were unable to identify all symptoms associated with UCL injury, representing the most concerning findings of the present study.

A Field-expedient Arm Care Screening Tool Can Identify Musculoskeletal Risk Factors in Baseball Players.

Preseason movement screening can identify modifiable risk factors, deterioration of function, and potential for injury in baseball players. Limited resources and time prevent high school baseball coaches from performing movement screens on their players. The arm care screen (ACS) will be highly sensitive to detecting musculoskeletal risk factors. Cross-sectional. Level 3. A total of 150 baseball players were independently scored on the ACS electronically by reviewing a video recording of each player's screening performance. Discriminability of the ACS was determined with a 2 × 2 contingency table dichotomizing musculoskeletal risk factors as present or absent based on a predetermined cutoff value and those who passed or failed the corresponding ACS subtest. High sensitivity was observed on the reciprocal shoulder mobility (0.89; 95% CI 0.81-0.94), 90/90 total body rotation (0.86; 95% CI 0.79-0.92), and lower body diagonal reach (0.85; 95% CI 0.78-0.91) tests of the ACS suggesting sufficient ability to identify musculoskeletal impairments and risk factors. The ACS is a simplistic screening tool that the coach can administer to discriminate between youth, high school, and college-level baseball players who possess musculoskeletal risk factors. The ACS subtests demonstrated high sensitivity for correctly identifying musculoskeletal risk factors common in baseball players and can be useful as a screening tool for baseball coaches developing arm care exercise programs. A field-expedient screen could provide coaches the ability to identify musculoskeletal risk factors that need to be addressed to minimize injury risk factors in a time-efficient manner.

Sites of flexor-pronator muscle injury and relationship between ulnar collateral ligament injury and flexor-pronator muscle injury in baseball players: a retrospective cohort study.

Ulnar collateral ligament (UCL) and flexor-pronator muscle (FPM) injuries are common in baseball players. However, the sites of FPM injuries and the relationship between UCL and FPM injuries in baseball players have not been fully clarified. The purpose of this study was to identify the sites of FPM injuries and to determine the relationships of location and severity of UCL injury with the presence of FPM injuries in baseball players. UCL and FPM injuries were diagnosed using magnetic resonance imaging in 99 baseball players. The sites of FPM injuries were identified on coronal, sagittal, and axial images. UCL injury severity was classified into four grades: chronic changes, low-grade partial tear, high-grade partial tear, and complete tear. UCL injury location was classified as proximal UCL tear or distal UCL tear. All images were assessed by a musculoskeletal radiologist and an orthopedic surgeon. Combined UCL and FPM injuries were observed in 45 of 99 players, of which 40 of 45 (89%) involved injury of the flexor digitorum superficialis (FDS). All FDS injuries were in the deep layer of the muscle belly. There was no significant difference between the severity of UCL injury and presence of FPM injuries (P=.352). There was a significant association of distal UCL tears with FPM injuries (P<.001). FDS injury occurs most commonly in the muscle belly of the second and fifth digits. There may be no relationship between the severity of UCL injury and presence of FPM injury in baseball players. FPM injuries may be a contributing factor in the failure of nonoperative management of distal UCL tears in baseball players.

Effect of introducing ultrasonography in medical examinations for elbow injuries among young baseball players.

This study investigated the usefulness of ultrasonography in medical examinations for detecting elbow injuries, especially capitellar osteochondritis dissecans, among young baseball players. Players with current or previous elbow joint pain were enrolled. Medical examinations (range of motion, tenderness, and stress tests) were performed with (2012-2016) or without (2007-2011) ultrasonography. Players with abnormal examination results were advised to undergo additional examinations at a local orthopedic clinic. Differences in the rates of capitellar osteochondritis dissecans detection, secondary examination, and elbow injury prevalence were compared between players who did and did not undergo ultrasonography. We identified 1045 baseball players, aged 9-12years, who required medical examinations for elbow injuries. Medical examinations without ultrasonography were performed in 346 players (group A), and examinations with ultrasonography were performed in 556 players (group B). Capitellar osteochondritis dissecans was present in 0.3% (1/346) of group A players and 3.0% (17/556) of group B players (p = 0.003). The secondary examination consultation rates were 51.2% (62/121) and 66.0% (270/409) in groups A and B, respectively (p = 0.004). Ultrasonography performed as a part of a medical examination can help detect elbow injuries, especially capitellar osteochondritis dissecans, in baseball players. Using ultrasonography in conjunction with medical examinations may contribute to a better understanding of elbow injuries in baseball players and improve consultation rates. Thus, ultrasonography is essential for the evaluation of elbow injuries in young baseball players.

Thoracic hyperkyphosis and its improvement in high-school baseball players

Hyperkyphosis is one of the risk factors for medial elbow injuries in baseball players. The purpose of this study was to determine the prevalence of hyperkyphosis in high school baseball players (Experiment 1) and to investigate the acute effects of spine mat usage in improving hyperkyphosis in high school baseball players (Experiment 2). Experiment 1: A study of 142 high school baseball players was conducted. A Spinal Mouse® was used to measure the thoracic kyphosis angle (TKA) with participants in an upright position. Hyperkyphosis was defined as a TKA of >40° in this study. The results showed that the prevalence of hyperkyphosis was 20.4% (29/142). Experiment 2: The participants were 56 high-school baseball players. For the intervention, the participant was placed in a supine position on a bed, and a spine mat was inserted such that it adhered to the thoracic spine. The primary outcome variable was TKA measured in the upright position using a spinal mouse before and after intervention with a spine mat. Based on this evaluation, we assigned the participants to two groups: hyperkyphotic (n =18) and non-hyperkyphotic (n=38). There were significant differences in pre- and post-test TKA in both groups (hyperkyphotic group: pre-test 44.4±3.8°, post-test 39.9±4.6°, P < 0.01; non-hyperkyphotic: pre-test 31.8±5.7°, post-test 29.2±7.8°, P < 0.01). The results of this study indicate a high prevalence of hyperkyphosis in high school baseball players. In addition, using a spine mat may lead to an acute improvement in hyperkyphosis in high school baseball players.

The Intra- and Inter-rater Reliability of an Arm Care Screening Tool in High School Baseball Coaches.

BackgroundPreseason movement screening can identify modifiable risk factors, deterioration of function, and potential for injury in baseball players. Limited resources and time intensive testing procedures prevent high school coaches from accurately performing frequent movement screens on their players.PurposeTo establish the intra-rater and inter-rater reliability of a novel arm care screening tool based on the concepts of the Functional Movement Screen (FMS™) and Selective Functional Movement Assessment (SFMA™) in high school coaches.Study DesignMethodological intra- and inter-rater reliability studyMethodsThirty-one male high school baseball players (15.9 years ± 1.06) were independently scored on the Arm Care Screen (ACS) by three examiners (two coaches, one physical therapist) in real-time and again seven days later by reviewing video recordings of each players’ initial screening performance. Results from each examiner were compared within and between raters using Cohen’s kappa and percent absolute agreement.ResultsSubstantial to excellent intra-rater and inter-rater reliability were established among all raters for each component of the ACS. The mean Cohen’s kappa coefficient for intra-rater reliability was 0.76 (95% confidence interval, 0.54-0.95) and percent absolute agreement ranged from 0.82-0.94 among all raters. Inter-rater reliability demonstrated a mean Cohen’s kappa value of 0.89 (95% confidence interval, 0.77-0.99) while percent absolute agreement between raters ranged from 0.81-1.00. Intra- and inter-rater reliability did not differ between raters with various movement screening experience (p>0.05).ConclusionsHigh school baseball coaches with limited experience screening movement can reliably score all three components of the ACS in less than three minutes with minimal training.Level of EvidenceLevel 3, Reliability study

Ulnar Collateral Ligament Injury in Gymnasts: An Analysis of Return to Competition Rates and Patient Outcomes

Objectives:While results following ulnar collateral ligament (UCL) injury in baseball players has been well documented, results following UCL injury in gymnasts are not well documented. As such, the purpose of this study was to report the operative and non-operative outcomes of UCL injury in gymnasts.Methods:Gymnasts who underwent UCL injury treatment whether non-operative or operative at a single institution were evaluated at a minimum of 2 years post-operatively. Patients were assessed with Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow Score (KJOC), Mayo Elbow Performance Score (MEPS), Andrews-Timmerman (A-T) Elbow score, Quick Disabilities of the Arm, Shoulder and Hand (qDASH) score and a custom return to play survey.Results:There were 11 patients who met inclusion criteria and complete follow-up was available in 9 patients. Overall, 6 patients were treated operatively (4 UCL reconstructions (UCLR) and 2 UCL repairs) and 3 patients were treated non-operatively. One UCLR was performed after 2 months of failed non-operative management. All patients were female with a mean age of 16.1 (range, 12-20) and mean BMI of 24.46 (range 19.2-34.1) at time of surgery or initial visit. Average follow-up was 4.04 years.Overall, 66.7% of operative versus 100% of non-operative were able to RTP at an average of 7.5 and 7 months, respectively. One re-injury was reported in the non-operative group, which was a re-dislocation of the elbow unrelated to gymnastics and was ultimately treated non-operatively. The mean KJOC, MEPS, A-T and qDASH scores for the operative group were 70.0 (range, 48.5-89), 97.5 (range, 95-100), 90.8 (range, 75-100) and 24.6 (range, 22.7-29.5), respectively. The mean scores for the non-operative group were 75.9 (range, 61-91.2), 71.7 (range, 65-75), 71.7 (range, 55-80) and 34.1 (range, 22.7-40.9), respectively.Conclusions:Both operative and non-operative treatments can be offered as successful treatment options for UCL injuries in gymnasts. Further investigation is needed to determine the optimal management of UCL injuries in gymnasts.

Lateral Abdominal Muscle Symmetry And Risk Of Sports Injury In Baseball Players

Lateral abdominal muscles play a significant role in trunk control and rotation during baseball batting. Repetitive and unidirectional baseball batting could lead to asymmetric hypertrophy of lateral abdominal muscles. This adaptive change may subsequently impose abnormal loads on the spine and predispose baseball players to sports injury. No study has examined whether adolescent baseball players present lateral abdominal muscle asymmetry and its relationship with risk of sports injury. PURPOSE: This study aimed to compare the thickness of lateral abdominal muscles on both sides of the trunk, and to investigate whether asymmetry of lateral abdominal muscle thickness was correlated with risk of sports injury in high school baseball players METHODS: Fifteen position players from a high school baseball team (right-handed batting and throwing; aged 16.0 ± 1.1 years, height 172.6 ± 5.0 cm, weight 73.3 ± 10.8 kg) completed the Functional Movement Screen (FMS) testing. B-mode ultrasound images were recorded from the external abdominal oblique (EO), internal abdominal oblique (IO), and transverse abdominis (TA) at the end of expiration in the crook-lying position. The absolute thickness of each lateral abdominal muscle for both sides was determined and compared using paired t-tests. The relationship between the asymmetry ratio (difference between two sides expressed as a percent of the dominant side) and FMS composite score was analyzed using the Spearman correlation coefficient. RESULTS: The EO thickness was significantly greater in the dominant side than in the non-dominant side (6.85 ± 1.13 vs. 5.05 ± 1.46 mm, p < 0.001), and the TA thickness was significantly greater in the non-dominant side than in the dominant side (4.21 ± 0.85 vs. 3.49 ± 0.60 mm, p = 0.003). Only the asymmetry ratio of TA was significantly correlated with the FMS composite score (r = 0.54, p = 0.040). CONCLUSIONS: High school baseball players showed side-to-side thickness asymmetry in the EO and TA. The significant correlation between the TA asymmetry ratio and FMS composite score suggests an increased risk of sports injury. High school baseball teams should consider integrating TA training into players’ routine training program. Supported by the Ministry of Science and Technology of Taiwan (MOST 108-2410-H-006-098)

Regional Interdependence and the Role of the Lower Body in Elbow Injury in Baseball Players: A Systematic Review

Background: Elbow injuries are exceedingly common in baseball players. Previous studies have identified that upper extremity strength and range of motion deficits pose a risk for these injuries, but few studies have examined the effect of lower extremity deficits. Given the role of the lower extremity in the kinetic chain of the baseball throwing motion, lower body deficits may affect the kinematics of the upper extremity and play a role in the elbow injury of baseball players. Purpose: To systematically review the current literature investigating the association of trunk and lower extremity deficits with elbow pain or injury in baseball players. Study Design: Systematic review. Methods: A systematic review of the literature was performed according to the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines to identify and analyze all previous studies focused on the association of elbow pain and/or injury with functional deficits of the trunk and lower extremities. Results: A total of 14 studies met inclusion criteria, examining a range of baseball players extending from youth to professional athletes. One of the 14 studies examined other types of overhead throwing athletes alongside baseball players. Lower extremity–related risk factors for elbow pain and injury in these athletes were found and stratified per level of play. Factors included specific hip range of motion, lower extremity injury or pain, balance, and foot arch posture. Associations were also found with lower extremity injury and noncompliance with primary prevention programs. Conclusion: Specific lower extremity deficits were found to be independent risk factors for elbow pain and injury in throwing athletes at certain levels of play. Additionally, prevention programs designed to correct deficits in identified risk factors were effective in reducing the incidence of elbow injury in youth athletes. These results highlight the potential of screening and subsequent intervention to reduce the incidence of elbow injury in certain subsets of baseball players.

The Relationship Between Humeral Torsion and Arm Injury in Baseball Players: A Systematic Review and Meta-analysis.

Humeral torsion (HT) has been linked to various injuries and benefits. However, the exact interplay between HT, shoulder range of motion (ROM), competition level differences, and injury risk is unclear. To determine the relationship between HT, ROM, and injury risk in baseball players. Secondarily, to determine HT based on competition level. PubMed, Embase, Web of Science, CINAHL, and Cochrane databases were searched from inception until November 4, 2018. Inclusion criteria consisted of (1) HT measurements and (2) arm injury or shoulder ROM. Systematic review. Level 3. Two reviewers recorded patient demographics, competition level, HT, shoulder ROM, and injury data. A total of 32 studies were included. There was no difference between baseball players with shoulder and elbow injuries and noninjured players (side-to-side HT difference: mean difference [MD], 1.75 [95% CI, -1.83 to 2.18]; dominant arm: MD, 0.17 [95% CI, -1.83 to 2.18]). Meta-regression determined that for every 1° increase in shoulder internal rotation (IR), there was a subsequent increase of 0.65° in HT (95% CI, 0.28 to 1.02). HT did not explain external rotation (ER ROM: 0.19 [95% CI, -0.24 to 0.61]) or horizontal adduction (HA ROM: 0.18 [95% CI, -0.46 to 0.82]). There were no differences between HT at the high school, college, or professional levels. No relationship was found between HT and injury risk. However, HT explained 65% of IR ROM but did not explain ER ROM or HA ROM. There were no differences in HT pertaining to competition level. The majority of IR may be nonmodifiable. Treatment to restore and maintain clinical IR may be important, especially in players with naturally greater torsion. HT adaptation may occur prior to high school, which can assist in decisions regarding adolescent baseball participation.

Partial-Thickness Rotator Cuff Tear by Itself Does Not Cause Shoulder Pain or Muscle Weakness in Baseball Players

Background: Partial-thickness rotator cuff tears are common shoulder injuries in baseball players. For some tears, the symptoms can be relieved through physical therapy or debridement without rotator cuff repair. Purpose: To assess whether partial-thickness rotator cuff tear by itself causes shoulder pain and muscle weakness in baseball players. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We studied 87 university baseball players (age, 19.5 ± 0.8 years; baseball career, 11.5 ± 1.6 years). All data were obtained during a full-participation annual medical check in 1 team. Rotator cuff tendons were examined ultrasonographically and allocated to 4 groups: (1) no tear, (2) supraspinatus tendon tear, (3) infraspinatus tendon tear, and (4) both supraspinatus and infraspinatus tendon tears. Current shoulder pain and shoulder muscle strength (dominant/nondominant) in abduction, external rotation, and internal rotation were compared by using chi-square and t tests. All players could play baseball with or without shoulder pain in this study. Results: Of the 87 players, 41 (47%) had articular-sided partial-thickness rotator cuff tears diagnosed on ultrasonography; the remaining 46 athletes were tear-free. Of the 41 affected patients, 19 had tears in the supraspinatus, 13 in the infraspinatus, and 9 in both the supraspinatus and infraspinatus tendons. Tear depth (mean ± SD) was 4.6 ± 2.3 mm in the supraspinatus and 6.2 ± 3.6 mm in the infraspinatus. Neither the rate of shoulder pain nor muscle strength differed significantly among the 4 groups (P = .96 and P = .15-.70, respectively). Conclusion: Articular-sided partial-thickness rotator cuff tear—by itself—did not cause shoulder pain and muscle weakness in university baseball players. Most so-called articular-sided partial-thickness rotator cuff tears may not be pathologic tendon tears.