Elbow injuries in the throwing athlete

Shoulder and Elbow Injuries in Adult Overhead Throwers: Imaging Review

Overhead throwing, particularly in baseball, subjects the shoulder and elbow to various unique injuries. Capsular contracture following repetitive external rotation shifts the humeral head posterosuperiorly, predisposing to glenohumeral internal rotation deficit (GIRD), Bennett, posterosuperior internal impingement (PSI), and superior labrum anterior-posterior (SLAP) lesions. GIRD represents loss of internal rotation at the expense of external rotation. Bennett lesion represents ossification of the posteroinferior glenohumeral ligament due to repetitive traction. PSI manifests with humeral head cysts and "kissing" tears of the posterosuperior cuff and labrum. Scapular dysfunction contributes to symptoms of PSI and predisposes to labral or rotator cuff disease. "Peel-back" or SLAP lesions occur when torsional forces detach the biceps-labral anchor from the glenoid. Finally, disorders of the anterior capsule, latissimus dorsi, teres major, and subscapularis are well recognized in overhead throwers. At the elbow, injuries typically involve the medial-sided structures. The ulnar collateral ligament (UCL) is the primary static restraint to valgus stress and can be thickened, attenuated, ossified, and/or partially or completely torn. Medial epicondylitis can occur with tendinosis, partial tear, or complete rupture of the flexor-pronator mass and can accompany UCL tears and ulnar neuropathy. Posteromedial impingement (PMI) and valgus extension overload syndrome are related entities that follow abundant valgus forces during late cocking or acceleration, and deceleration. These valgus stresses wedge the olecranon into the olecranon fossa, leading to PMI, osteophytes, and intra-articular bodies. Other osseous manifestations include olecranon stress fracture and cortical thickening of the humeral shaft. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Incidence of Repeat Elbow Capsular Release After Arthroscopic Elbow Capsular Release

Background

Elbow capsular release can be performed arthroscopically or through an open method to improve range of motion (ROM). However, it is unclear how frequently patients require an open capsular release after unsatisfactory results from an arthroscopic release.

Purpose/Hypothesis

The purpose of this study was to determine the percentage of patients who underwent an arthroscopic elbow release for loss of motion who then required a repeat elbow capsular release or other subsequent surgery on the same elbow. It was hypothesized that patients who underwent arthroscopic elbow release would rarely (<5%) require a subsequent elbow release.

Study Design

Case series; Level of evidence, 4.

Methods

Patients who underwent arthroscopic elbow capsular release from January 1, 2010, to December 31, 2019, were identified by chart review and procedure code. Demographic parameters, pre- and postoperative ROM, and surgical history were collected by chart review. Follow-up data included patient satisfaction and the Timmerman-Andrews (TA) elbow score. Data were compared between patients who did and those who did not require subsequent elbow surgery.

Results

Overall, of 140 study patients (116 male, 24 female; mean age, 49.6 years), 18 (12.9%) required subsequent surgery, including 6 capsular releases (4.3%; 1 open and 5 arthroscopic). The most common follow-up procedure was ulnar nerve releases/transpositions (n = 7). Total arc of elbow motion (flexion to extension) improved by a mean of 51.4°. The mean TA score was 76.5 ± 20.4 at a mean of 5.25 years postoperatively. Mean satisfaction score was 77.6 ± 26.3. In this study, 82.4% of patients stated that their symptoms either improved or resolved completely. Patients who required subsequent surgery had a significantly lower preoperative total arc of elbow motion versus those who did not require subsequent surgery (P = .046). There was no difference between the groups in symptom resolution, satisfaction, ROM, or TA score (P ≥ .279 for all).

Conclusion

After arthroscopic elbow release, <5% of patients required a repeat elbow capsular release, 12.9% required some form of follow-up elbow surgery, and 4.3% had a new injury of the elbow. Overall, patients saw improvement in elbow ROM, but many still had residual symptoms from their underlying disease after arthroscopic elbow capsular release.

Ultrasonography of the pediatric elbow

Ultrasound of the elbow can be incorporated into routine pediatric practice in the radiology department, emergency department, orthopedic clinic, and interventional suite. Ultrasound is complementary to radiography and magnetic resonance imaging for the evaluation of elbow pain in athletes with overhead activities or valgus stress, focusing on the ulnar collateral ligament medially and capitellum laterally. As a primary imaging modality, ultrasound can be used for a variety of indications including inflammatory arthritis, fracture diagnosis, and ulnar neuritis/subluxation. Ultrasound is also well-suited to guide diagnostic and therapeutic elbow joint interventions with precise localization of anatomic landmarks and needle placement. Here, we describe technical aspects of elbow ultrasound and illustrate its application in pediatric patients from infants to teen athletes.

Acute and Chronic Elbow Disorders

Elbow pain is very common and can be due to many pathologic conditions. After radiographs are obtained, advanced imaging is often necessary. Both ultrasonography and MR imaging can be used to evaluate the many important soft-tissue structures of the elbow, with each modality having advantages and disadvantages in certain clinical scenarios. Imaging findings between the two modalities often correlate. It is important for musculoskeletal radiologists to understand normal elbow anatomy and how best to use ultrasonography and MR imaging to evaluate elbow pain. In this way, radiologists can provide expert guidance to referring clinicians and best guide patient management.

Osteochondritis dissecans of the knee: Epidemiology, etiology, and natural history

Osteochondritis dissecans of the knee is a disease that typically affects skeletally immature patients. Clinically manifested with knee pain, limping, and joint disfunction, this condition has remained misunderstood and undervalued for a long period. Although being a rare condition, its awareness is of utmost clinical interest because of the possible severe consequences it can bring when misrecognized or inadequately treated. Its etiology remains unclear and is still debated. Many theories have been proposed, including inflammation, local ischemia, subchondral ossification abnormalities, genetic factors, and repetitive mechanical microtrauma, with a likely interplay of the same. This review article aims to deliver and discuss current and up-to-date concepts on epidemiology, etiology, and natural history of this pediatric condition. Level of evidence: level V.

Forearm Flexor Tendon Injury in Adolescent Athletes: Risk Factors, Treatment, and Prevention

ABSTRACT

Injury to the flexor pronator mass is a common condition that is especially prevalent in overhead throwing athletes. The increasing incidence of these injuries has promoted considerable efforts in research to better understand the pathology, risk factors, and potential mechanisms to prevent injury in these athletes. While there are numerous intrinsic and extrinsic factors associated with injury, a common theme involves chronic overuse and microtrauma with inadequate resting intervals between performances. The purpose of this review is to discuss medial elbow injuries in young athletes with a particular focus on the flexor pronator mass.

Lateral epicondylosis: A literature review to link pathology and tendon function to tissue-level treatment and ergonomic interventions

BACKGROUND

Common treatments for lateral epicondylosis (LE) focus on tissue healing. Ergonomic advice is suggested broadly, but recommendations based on biomechanical motion parameters associated with functional activities are rarely made. This review analyzes the role of body functions and activities in LE and integrates the findings to suggest motion parameters applicable to education and interventions relevant to activities and life roles for patients.

PURPOSE

This study examines LE pathology, tendon and muscle biomechanics, and population exposure outlining potentially hazardous activities and integrates those to provide motion parameters for ergonomic interventions to treat or prevent LE. A disease model is discussed to align treatment approaches to the stage of LE tendinopathy.

STUDY DESIGN

Integrative review METHODS: We conducted in-depth searches using PubMed, Medline, and government websites. All levels of evidence were included, and the framework for behavioral research from the National Institutes of Health was used to synthesize ergonomic research.

RESULTS

The review broadened the diagnosis of LE from a tendon ailment to one affecting the enthesis of the capitellum. It reinforced the continuum of severity to encompass degeneration as well as regeneration. Systematic reviews confirmed the availability of evidence for tissue-based treatments, but evidence of well-defined harm reducing occupational interventions was scattered amongst evidence levels. Integration of biomechanical studies and population information gave insight into types of potentially hazardous activities and provided a theoretical basis for limiting hazardous exposures to wrist extensor tendons by reducing force, compression, and shearing during functional activities.

CONCLUSIONS

These findings may broaden the first treatment approach from a passive, watchful waiting into an active exploration and reduction of at-risk activities and motions. Including the findings into education modules may provide patients with the knowledge to lastingly reduce potentially hazardous motions during their daily activities, and researchers to define parameters of ergonomic interventions.

Evaluation and management of elbow injuries in the adolescent overhead athlete

With an increased interest in youth sports, the burden of overhead throwing elbow injuries accompanying early single-sport focus has steadily risen. During the overhead throwing motion, valgus torque can reach and surpass Newton meters (N m) during the late cocking and early acceleration phases, which exceeds the tensile strength (22.7–33 N m) of the ulnar collateral ligament. While the ulnar collateral ligament serves as the primary valgus stabilizer between and degrees of elbow flexion, other structures about the elbow must contribute to stability during throwing. Depending on an athlete’s stage of skeletal maturity, certain patterns of injury are observed with mechanical failures resulting from increased medial laxity, lateral-sided compression, and posterior extension shearing forces. Together, these injury patterns represent a wide range of conditions that arise from valgus extension overload. The purpose of this article is to review common pathologies observed in the adolescent overhead throwing athlete in the context of functional anatomy, osseous development, and throwing mechanics. Operative and non-operative management and their associated outcomes will be discussed for these injuries.

Ultrasound Examination Techniques for Elbow Injuries in Overhead Athletes

Elbow pain is a frequent complaint among overhead athletes. Standard evaluation of the elbow uses history and physical examination, with radiographic imaging and MRI aiding in the confirmation of diagnosis. Musculoskeletal ultrasonography (US) provides dynamic, functional assessment of tendons and ligaments in the elbow, allowing the visualization of structures under stress and motion. Stress US offers the ability to detect injuries to the ulnar collateral ligament by measuring changes in joint space under stress. The freedom of dynamic imaging means results are dependent on the skill of the US operator to obtain the most accurate and complete evaluation. US is cost efficient and portable, allowing for quick examination at the point of care. This article provides a technique guide for sports medicine specialists performing US examination of the elbow.

Scapular muscles strength in college baseball players with and without a history of UCL injury

BACKGROUND

Ulnar collateral ligament (UCL) injuries are common in overhead athletes and have increased in prevalence among baseball pitchers of all ages. The purpose of this study was to examine the difference between the strength of five scapular stabilizing muscles in college baseball pitchers with and without a history of UCL surgery. Data on a pitcher with a recent diagnosis of a Grade I UCL sprain was also included as a case study.

METHODS

Thirty-nine college baseball pitchers, eight pitchers with a history of UCL surgery, volunteered to participate. Each participant completed a self-guided warm-up and then the strength of five scapular stabilizing muscles were assessed using a hand-held dynamometer. Station one tested latissimus dorsi and serratus anterior while the middle trapezius, lower trapezius, and rhomboids were assessed at station two. To determine the difference between groups Mann-Whitney U tests were performed with a significance level of P≤0.05.

RESULTS

The results showed no significant difference in muscle strength for all five muscle strength tests between the two groups. Although not statistically significant, the injured group averaged greater strength than the non-injured group for all five muscles tested.

CONCLUSIONS

The results of this study indicated there was no difference is scapular stabilizing muscle strength between college baseball pitchers with and without a history of UCL surgery. This may be due to proper rehabilitation and rest following the UCL injury. More research is needed to determine the role of scapular stabilizing muscle strength on elbow and UCL injury in college baseball players.

Imaging of the post-operative medial elbow in the overhead thrower: common and abnormal findings after ulnar collateral ligament reconstruction and ulnar nerve transposition

Ulnar collateral ligament (UCL) reconstruction is now being performed more commonly and on younger patients than in prior decades. As a result, radiologists will increasingly be asked to evaluate elbow imaging of patients presenting with pain who have had UCL reconstruction. It is essential for radiologists to understand the normal and abnormal imaging appearances after UCL reconstruction and ulnar nerve transposition, which is also commonly performed in overhead-throwing athletes. Doing so will allow radiologists to provide accurate interpretations that appropriately guide patient management.

Ultrasound-Assisted Assessment of Medial Elbow Stability

OBJECTIVES

An assessment of medial elbow stability is essential to the patient with an ulnar collateral ligament injury. Ultrasound imaging can be used to assess medial elbow stability. This study determined the effect of the elbow flexion angle on the medial elbow joint space during clinical tests of medial elbow stability.

METHODS

Ultrasound images of the nondominant elbow were collected during 3 tests of medial elbow stability: valgus stress test, weighted valgus test, and milking maneuver. The elbow flexion angle increased between the valgus stress test and milking maneuver. The width of the medial joint space was measured on ultrasound images collected in unstressed and stressed conditions.

RESULTS

Across test conditions, the medial joint width was greater in the stressed condition (mean ± SD, 3.7 ± 0.1 mm) than in the unstressed condition (2.9 ± 0.09 mm). The medial elbow joint space width was less (mean difference, 0.16 ± 0.01 mm; P = .01) in the milking maneuver position compared to the valgus stress test positions.

CONCLUSIONS

This study provides evidence that changes in the width of the medial elbow during clinical evaluation of the unimpaired elbow can be detected by ultrasound. Changing the elbow flexion angle did not affect the change in width of the medial elbow during valgus loading.

Relationship between tibial spine size and the occurrence of osteochondritis dissecans: an argument in favour of the impingement theory

PURPOSE

Pathophysiology of osteochondritis dissecans (OCD) of the medial femoral condyle remains uncertain. Specifically, the relationship between the size of the anterior tibial spine (ATS) and the presence of OCD has not been explored. The purpose of this study was to evaluate the relationship between ATS size and the occurrence of OCD.

METHODS

Seventy-nine children between 8 and 17 years of age were included in two groups: OCD (n = 37) and control (n = 42). The groups were matched in terms of age, gender, BMI and weight. Two independent observers performed an MRI analysis of the size of the tibial spine and intercondylar notch relative to the size of the respective epiphyses. For this study, the "S ratio" was calculated by dividing the height of the tibial spine by the height of the tibial epiphysis. The "N ratio" was calculated by dividing the height of the notch by the height of the femoral epiphysis. These two ratios for both groups were compared using Student's t test.

RESULTS

The mean value of the S ratio in the OCD group was 0.39 ± 0.06; the mean value of the S ratio in the control group was 0.32 ± 0.03 (P = 0.004). The mean value of the N ratio in the OCD group was 0.70 ± 0.08; the mean value of the N ratio in the control group was 0.70 ± 0.07 (n.s.).

CONCLUSION

This study's findings confirm our hypothesis that patients with OCD have a more prominent tibial spine than in patients without OCD.

LEVEL OF EVIDENCE

IV.

Pathologies of the shoulder and elbow affecting the overhead throwing athlete

The overhead-throwing athlete is susceptible to a variety of predictable disease entities affecting the shoulder and elbow. While the pathophysiology and nomenclature of these diseases are ubiquitous throughout the clinical literature, this information is sparse within the radiology domain. We provide a comprehensive review of these unique injuries with accompanying imaging features in an effort to enhance the role of the radiologist during the management of the overhead thrower. When appropriately recognized and described, the imaging features aid in establishing a diagnosis and ultimately the implementation of appropriate clinical management.

Surgical management of acute claw hand in a competitive baseball player

We describe an unusual case of acute ulnar neuropathy with a flexible claw hand deformity in a baseball pitcher. Treatment involved ulnar nerve decompression at the elbow with subsequent recurrence of symptoms upon return to pitching. Definitive treatment included a wide secondary release of tethered locations resulting in return of function. At final follow-up the patient has returned to unrestricted baseball throwing activities.

Factors Related to Increased Ulnar Collateral Ligament Thickness on Stress Sonography of the Elbow in Asymptomatic Youth and Adolescent Baseball Pitchers

BACKGROUND

Stress ultrasound (SUS) of the elbow has demonstrated changes in the anterior band of the ulnar collateral ligament (UCL) in professional and high school-aged pitchers. However, there have been no large reports correlating pitching history data with SUS changes in youth and adolescent baseball pitchers.

HYPOTHESIS

Changes of the UCL on SUS will correlate with pitching volume in youth and adolescent baseball pitchers.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

SUS of the elbow was performed in both elbows of 102 youth and adolescent baseball pitchers. UCL thickness and the width of the ulnohumeral joint, at rest and with 150 N of valgus stress, were measured using a standardized, instrumented device. Demographic data, arm measurements, and a pitching history questionnaire were recorded as well. The pitchers were separated into 2 groups based on age: group 1 (12-14 years) and group 2 (15-18 years). SUS findings of the dominant elbows were compared between the 2 groups. Correlation analysis and linear regression were used to identify relationships between SUS findings and pitching history data.

RESULTS

In all pitchers, the mean UCL thickness was 4.40 mm in the dominant elbow and 4.11 mm in the nondominant elbow (P =.03). There was no significant difference between elbows in any joint space characteristics. A comparison of group 1 versus group 2 demonstrated significant differences in UCL thickness (4.13 vs 4.96 mm; P < .001), resting joint space width (6.56 vs 4.04 mm; P < .001), and stressed joint space width (7.68 vs 4.07 mm; P < .001). There was no difference in the change in joint space width between the 2 groups (1.11 vs 0.76 mm; P = .05). The UCL was significantly thicker in pitchers who threw more than 67 pitches per appearance (4.69 vs 4.14 mm), who pitched more than 5 innings per appearance (4.76 vs 4.11 mm), and who had more than 5.5 years of pitching experience (4.71 vs 4.07 mm; P < .001). Linear regression demonstrated that age, weight, and pitches per appearance (R ² = 0.114, 0.370, and 0.326, respectively) significantly correlated with UCL thickness.

CONCLUSION

These findings suggest that UCL thickness increases as pitchers get older and heavier and as they increase their pitch volumes.

Elbow Injuries in the Young Throwing Athlete

Baseball pitchers and other throwing athletes place their elbows under tremendous stresses, making them vulnerable to a number of unique injuries. Skeletally immature throwers in particular are at a greater risk for growth plate and other bony injuries, due to the relative strengths of these tissues and the kinematics involved in throwing. Care should be taken to fully evaluate these injuries based on the particular history and presentation to properly direct treatment and rehabilitation. Patients, as well as other athletes, coaches, and families, also should be made aware of the significant risk factors for these injuries, especially those regarding pitch limits, proper mechanics, and sufficient rest.

Disproportionate trends in ulnar collateral ligament reconstruction: projections through 2025 and a literature review

BACKGROUND

Medial ulnar collateral ligament (UCL) injuries of the elbow that require surgical management are uncommon. There is growing evidence, however, suggesting that the incidence of UCL reconstruction (UCLR) procedures is rapidly increasing. We sought to quantify the incidence of age-related trends for UCLR from 2003 to 2014 and subsequently to project future trends through 2025. We hypothesized that as the total number of UCLRs performed increased, a disproportionate incidence among younger patients would be observed.

METHODS

New York State's Statewide Planning and Research Cooperative System database was queried from 2003 to 2014 to identify individuals between 10 and 40 years old undergoing UCLR. Poisson regression was used to develop future projections for UCLR and New York State population through 2025, and incidence estimates per 100,000 people were calculated.

RESULTS

In New York State between 2003 and 2014, there were 890 patients who underwent UCLR, with average annual incidence per 100,000 people equaling 6.3 ± 2.8 for ages 15 to 19 years, significantly greater than for all other age groups (P < .001). Projections from 2015 through 2025 suggest that incidence in 15- to 19-year-olds and 20- to 24-year-olds will continue to rapidly increase while rates for other age groups will remain relatively stable.

CONCLUSIONS

The number of UCLRs performed between 2003 and 2014 increased by 343%, and a disproportionate trend in average annual incidence for patients between 15 and 19 years old was observed. As our review of the literature questioned outcomes in adolescent athletes after UCLR, continued attempts at preventing these injuries in the young throwing athlete remain paramount.