Medial elbow injuries in the throwing athlete.

There has been an epidemic increase in injuries to the elbow in our youth sports over the past 15 years. Initially, career-ending elbow injuries occurred almost exclusively in the professional population. The landmark procedure developed by Dr. Frank Jobe, colloquially termed "Tommy John surgery" after the initial player in whom he performed the surgical procedure, allowed roughly two-thirds of professional athletes to return to play at or near the same level. As the surgical procedure became more widespread, modifications of the technique by Jobe and many other contributors raised the return-to-play level to 85%-94% of players regaining the ability to return to sport at the preinjury level. Almost simultaneously, the emphasis on velocity in the professional ranks led to an unintentional increase in stress on the throwing elbow. This was magnified in our athletes by the advent of year-round sports, as well as the formation of "showcase" events to demonstrate skills and measure velocity. This, unfortunately, has resulted in an increase in both repetitive stress injuries and acute traumatic injuries in our young athletes. The purpose of this article is to discuss age-related injuries from both a preventative standpoint and a treatment standpoint.

Disabled throwing shoulder/elbow players have high rates of impaired foot function.

The prevalence of impaired foot function and floating toes of 91 baseball players with disabled throwing shoulder or elbow were retrospectively investigated. Foot function was evaluated by foot "rock paper scissors" and floating toes were confirmed if none of the toes made contact with the mat in standing posture. The prevalence of impaired foot function and floating toes and the relationship between between them were determined. Abnormal foot function was observed in 83 players (91%); of those, 73 players (88%) also had floating toes, and the prevalence was statistically significant compared to those without it (12%) (P < 0.001). Floating toes were observed in 74 players (81%); of those, 73 players (99%) had impaired foot function, and the prevalence was also statistically significant compared to those without them (59%) (P < 0.001). Baseball players with disabled throwing shoulder or elbow have high rates of impaired foot function and floating toes.

Risk factors for throwing elbow injuries during pitching analyzed by simulation using human musculoskeletal model in youth baseball pitchers.

BACKGROUND: Pitching mechanics are believed to be risk factors for throwing elbow injury. Thus, a prospective study of abnormal mechanics in youth baseball players is needed. This study aimed to analyze the ulnar collateral ligament during normal pitching using SIMM (Software for Interactive Musculoskeletal Modeling) for analysis and investigate the risk parameters of throwing elbow injuries in youth baseball players. We hypothesized that excessive ulnar collateral ligament force during pitching would be a risk factor for throwing elbow injuries in this population. METHODS: In this cohort study, youth baseball pitchers (aged 9-11 years) were instructed to throw a ball into a netted target. Using a SIMM musculoskeletal model, we analyzed the force of the anterior band of the anterior oblique ligament, posterior band of the anterior oblique ligament (AOL_PB), and elbow varus moment during pitching (foot contact to ball release). We calculated the integral of each force of the anterior band of the anterior oblique ligament and AOL_PB during pitching and summarized these data to establish an impulse at the medial epicondyle. Each participant was followed up for 12 months to assess the occurrence of throwing elbow injury. RESULTS: During the 12-month follow-up period, 18 pitchers (28.1%) reported throwing elbow injuries in the throwing arm. The results of this study showed that the maximum AOL_PB force and the impulse at the medial epicondyle were risk factors for throwing elbow injuries. The maximum AOL_PB force was significantly higher in the throwing elbow injury group than in the uninjured group (59.4 ± 17.8 N vs. 47.1 ± 17.5 N, P = .014). The impulse at the medial epicondyle was also significantly different (11.1 ± 4.0 N ï½¥ s in the throwing elbow injury group vs. 8.3 ± 4.4 N ï½¥ s in the uninjured group, P = .025). CONCLUSIONS: Increasing the AOL_PB force or the impulse at the medial epicondyle may increase the risk of throwing elbow injuries in youth baseball pitchers. It may be possible to reduce injury risk by focusing on ways to decrease AOL_PB load and cumulative stress on the medial epicondyle throughout the throwing motion while still maintaining high levels of ball velocity.

The biomechanical evaluation of a novel 3-strand docking technique for ulnar collateral ligament reconstruction in the elbow.

BACKGROUND AND HYPOTHESIS: The original 2-strand docking technique for elbow ulnar collateral ligament reconstruction has recently been modified to use a 3-strand graft. To date, no biomechanical study has compared the 2 techniques. We hypothesized that the 3-strand docking technique would restore valgus laxity to its native state, with comparable load-to-failure characteristics to the 2-strand docking technique. MATERIALS AND METHODS: Sixteen fresh cadaveric elbows were matched to the corresponding contralateral side from the same individual to create 8 matched pairs and were then randomized to undergo ulnar collateral ligament reconstruction using either the 2- or 3-strand technique. Valgus laxity and rotation measurements were quantified using a MicroScribe 3DLX digitizer at various flexion angles for the native state, transected state, and 1 of the 2 tested reconstructed ligaments. Each reconstruction was then tested to failure. RESULTS: Valgus laxity for the intact state at elbow flexion angles of 30°, 60°, 90°, and 120° was 7° ± 2°, 7° ± 2°, 6° ± 1°, and 5° ± 2°, respectively. These values were similar to those of both reconstruction techniques. On load-to-failure testing, there was no significant difference in any parameter recorded. Yield torques for the 3- and 2-strand reconstructions were 13.4 ± 4.80 N/m and 11.8 ± 4.76 N/m, respectively (P = .486). The ultimate torques were 15.7 ± 6.10 N/m and 14.4 ± 5.58 N/m for the 3- and 2-strand techniques, respectively (P = .582). CONCLUSION: The 3-strand docking technique was able to restore valgus laxity to the native state, with similar load-to-failure characteristics to the 2-strand docking technique.

Costal osteochondral autograft for reconstruction of advanced-stage osteochondritis dissecans of the capitellum.

BACKGROUND: Advanced-stage osteochondritis dissecans of the capitellum affecting the lateral wall may result in osteoarthritis, and suitable treatment is needed to avoid permanent deformation and impaired function. We aimed to assess postoperative outcomes of costal osteochondral autograft for treatment of this condition. METHODS: We included 22 young overhead athletes (mean age, 13.9 years) with advanced osteochondritis dissecans of the humeral capitellum who underwent costal osteochondral autograft. All patients had elbow pain and wide-range articular cartilage lesions. We evaluated clinical and radiographic outcomes at a mean follow-up of 27 months (range, 12-77 months). RESULTS: All patients achieved rapid functional improvement and returned to their former sports activity levels. The baseball players were able to play catch within 62 to 164 days (mean, 107 days) and returned to full pitching activity within 123 to 339 days (mean, 226 days). We assessed mean elbow function by the clinical rating system of Timmerman and Andrews and the Japanese Orthopaedic Association sports score; the scores improved from 121.5 and 53.7 points preoperatively to 169.2 points and 86.1 points, respectively, at the time of follow-up. Four patients required additional minor surgical procedures, including screw removal, loose body removal, and shaving off of spur formation. No patient showed obvious radiographic changes of osteoarthritis. All patients were satisfied with the final outcomes and had good functional recovery. CONCLUSION: Costal osteochondral autograft gave satisfactory results for advanced osteochondritis dissecans of the humeral capitellum with extensive lesions affecting the lateral wall.

Characteristics of ulnar neuropathy in baseball players: Focusing on the entrapment point of the ulnar nerve and valgus instability.

Background: The region where the ulnar nerve (UN) is swollen in baseball players with ulnar neuropathy is not apparent. This study investigated the UN's cross-sectional area (CSA) at each entrapment point in baseball players. We also aimed to clarify the relationship between valgus instability and the CSA of the UN. Methods: Forty baseball players were separated into healthy and ulnar neuropathy groups. The CSA and valgus instability were measured using ultrasonography (US). Relative to the medial epicondyle (MEC), the arcade of Struthers (SA) was 5 cm proximal, the cubital tunnel was the posterior part, and Osborne's ligament was defined as 3 cm distal. The ulnohumeral joint space was imaged as a low-echo space between the distal-medial corner of the trochlea and the proximal edge of the sublime tubercle. Results: The UN in the ulnar neuropathy group had significant swelling in the cubital tunnel and Osborne's ligament. We found a weak positive correlation between the CSA and ulnohumeral joint space, and the ulnohumeral joint space at rest and valgus stress. Conclusion: Evaluation and treatment of UN, especially cubital tunnel and Osborne's ligament, are necessary for the rehabilitation of baseball players presenting with ulnar neuropathy and valgus instability.

Assessment of the ulnar nerve stiffness during valgus stress of the elbow using shear wave elastography: an observational cross-sectional study.

BACKGROUND: Identification of the relationship between valgus stress in the medial elbow and ulnar nerve strain during maximum external rotation of the shoulder is pivotal for the prevention and management of ulnar neuropathies. In this observational cross-sectional study, we aimed to determine the changes in ulnar nerve stiffness under valgus stress at different nerve entrapment sites. METHODS: Twenty healthy baseball players participated in the study. The stiffness of the ulnar nerve on the throwing side was assessed at two sites, the arcade of Struthers and the Osborne's ligament, at 0°, 60°, and 90° flexion by shear wave elastography using a 10-MHz linear transducer. The arcade of Struthers was defined as the proximal site and the Osborne's ligament as the distal site. Valgus stress was applied to the medial elbow at 0, 30, 50, and 70 N using a Telos stress device, and the stiffness caused by valgus stress was measured. RESULTS: At all elbow flexion angles, the stiffness of the ulnar nerve under 70 N valgus stress was higher than that under 30 N stress. The stiffness of the ulnar nerve at the proximal site was significantly higher than that at the distal site. CONCLUSION: Valgus stress increases ulnar nerve stiffness. In addition, the stiffness of the proximal site increases.

Medial Elbow Injuries in the Throwing Athlete.

Medial elbow injuries in the throwing athlete are common and increasing in frequency. They occur due to repetitive supraphysiologic forces acting on the elbow during the overhead throw. Overuse and inadequate rest are salient risk factors for injury. Most athletes improve substantially with rest and nonoperative treatment, although some athletes may require surgical intervention to return to play. Because of advances in conservative and surgical treatments, outcomes after medial elbow injury have improved over time. Currently, most athletes are able to return to a high level of play after ulnar collateral ligament reconstruction and experience a low rate of complications.

Relationship Between Tightness of the Hip Joint and Elbow Pain in Adolescent Baseball Players.

BACKGROUND: Repetitive tensile stresses from valgus torque can induce elbow injury in adolescent baseball players. Insufficient hip range of motion (ROM) can change throwing mechanics, reducing the transfer of energy from the lower to the upper extremities. Thus, hip ROM limitations may force the upper extremities to bear the burden of a strong throw. Improper pitching mechanics caused by insufficient hip ROM are thought to increase valgus torque on the elbow when throwing, increasing the risk of elbow injury. PURPOSE: To investigate the relationship between elbow pain and hip ROM in adolescent baseball players. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 122 adolescent baseball players with a mean age of 12.0 years (range, 6-14 years) participated in this study. Elbow pain, hip flexion angle, and the internal rotation angles of the hip at 0° and 90° of flexion were assessed. Participants were divided into a pain group and a normal group based on the pain assessment, and each hip angle was compared between groups using Student t tests. P values <.05 were considered statistically significant. RESULTS: Thirty-one of 122 players had elbow pain. The hip flexion angle of the trail leg was 121.9° ± 12.3° for the normal group and 111.2° ± 11.3° for the pain group (P = .0001). The plant leg hip flexion angles were 122.0° ± 12.4° and 113.6° ± 11.3° (P = .0014) for the normal and pain groups, respectively. The internal rotation angle at 0° of hip flexion of the trail leg was 49.4° ± 12.6° and 45.6° ± 8.8° (not significant), and of the plant leg was 49.1° ± 12.5° and 48.7° ± 11.5° (not significant), for the normal and pain groups, respectively. The internal rotation of the trail leg at 90° of hip flexion was 46.9° ± 13.3° in the normal group and 36.1° ± 15.7° in the pain group (P = .0005). In the plant leg, the internal rotation angle at 90° of hip flexion was 46.9° ± 12.2° and 36.4° ± 18.1° for the normal and pain groups, respectively (P = .0013). CONCLUSION: Limitations to hip flexion and internal rotation at 90° of hip flexion were risk factors for elbow injury. Differences in internal rotation angles between 0° and 90° of hip flexion may be important criteria for identifying adolescent baseball players at risk of elbow pain.

Operative management of ulnar collateral ligament insufficiency in adolescent athletes.

BACKGROUND: The incidence of ulnar collateral ligament (UCL) injuries of the elbow has increased in adolescents over the past decade because of widespread participation in athletics and heightened awareness among physicians. HYPOTHESIS: Ulnar collateral ligament reconstruction using the docking technique would result in a successful return to athletic activity in this age group. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Study participants were 55 skeletally mature adolescent athletes (mean age, 17.6 years; range, 15-18 years) who underwent UCL reconstruction between 2008 and 2010. While the majority of patients were baseball players (n = 47), there were 3 gymnasts and 5 javelin throwers included in the study. Each patient underwent UCL reconstruction utilizing the docking technique after an adequate trial of nonoperative management (mean, 5.8 months). At the latest follow-up, patients were evaluated to determine their ability to return to athletic activity. Clinical outcomes were classified using the Conway scale, the Andrews-Timmerman score, and the Kerlan-Jobe Orthopaedic Clinic (KJOC) score. RESULTS: At a minimum 2-year follow-up, 87% (48/55) of patients had excellent results using the Conway scale. Overall, there were only 2 poor results (3.6%) that were observed in patients with concomitant osteochondritis dissecans lesions of the capitellum. There were 4 postoperative complications in 4 patients (2 gymnasts and 2 javelin throwers) who developed ulnar neuritis after UCL reconstruction. The mean Andrews-Timmerman score was 83.6 ± 7.2 (range, 30-100), and the mean KJOC score was 88.0 ± 6.0 (range, 40-100). CONCLUSION: The docking technique results in favorable clinical outcomes in adolescent athletes with UCL insufficiency at a minimum of 2 years postoperatively. Patients with concomitant intra-articular lesions should be cautioned preoperatively that they might experience inferior clinical outcomes. Postoperatively, adolescent gymnasts and javelin throwers may be at an increased risk for transient paresthesia of the ulnar nerve caused by increased stress on the medial elbow.