Little League Shoulder

Benjamin Friedman, MD
Resident Physician, SUNY Upstate
Department of Emergency Medicine

Anthony Klimek, MD
Sports Medicine Fellow Physician, SUNY Upstate
Department of Emergency Medicine

Paul Klawitter, MD, PhD
Attending Physician, SUNY Upstate
Department of Emergency Medicine

Case

HPI: A 14-year-old male presents to the clinic with pain in the upper arm. The patient is a Little League pitcher, and his pain has been worsening since he started practicing for the all-star team. The pain is aching and confined to the right shoulder. It is aggravated by throwing and continues to hurt after practice. Icing provides some relief. He denies any clicking or popping noises while throwing or any recent trauma.

Exam: The patient has minimal swelling of the right shoulder compared to the unaffected shoulder. There is no erythema or warmth. Internal rotation of the throwing arm in 90 degrees abduction is reduced compared to the unaffected arm. External rotation of the throwing arm is slightly increased. He has 5/5 strength bilaterally in all planes of motion without laxity or drawer. There is pain with resisted abduction of the affected shoulder when held in external rotation. When held in internal rotation, there is no pain with resisted abduction. There is no pain with adduction or forward flexion of either arm. There is tenderness to palpation over the lateral aspect of the proximal right humerus. O’Brien test for labral tear is negative. Hawkins-Kennedy test for impingement is negative. The Apprehension, Jobe, and Neer tests are all negative.

Differential Diagnosis: Proximal humeral epiphysiolysis, GIRD, rotator cuff tear, labral tear

Imaging: X-ray of bilateral shoulders in external rotation shows widening of the physis in the right arm compared to the left arm.

Final Diagnosis: Proximal humeral epiphysiolysis

Proximal Humeral Epiphysiolysis (Little League Shoulder)

Shoulder injuries are common in sports that involve repetitive throwing or racqueting motions, such as baseball, football, and tennis. This is especially true for young athletes who are skeletally immature. Proximal humeral epiphysiolysis, often referred to as Little League shoulder (LLS), is a common overuse injury associated with repetitive throwing activities. It occurs from a widening or fracture of the physis, manifesting as pain over the proximal humerus. LLS most commonly occurs in adolescent boys, especially baseball pitchers between the ages of 11 and 16, but can occur with any throwing or racqueting activity.

Pathophysiology and Mechanics

In adolescence, the proximal humeral physis is growing rapidly and is thus more susceptible to pathology. When the shoulder is externally rotated during throwing, there is maximal torque on the surrounding structures. High levels of torque in high repetition can cause microtrauma, devascularization, and damage to the epiphyseal cartilage, which is comparably weaker than the surrounding bony structures. This causes the physis to widen, resembling a Salter-Harris type I fracture. Repetitive throwing motion may also lead to other shoulder pathologies, such as stress fractures, labral tears, decreased humeral derotation, dead arm syndrome, and Bennett lesions. A table of associated shoulder pathologies is listed below.

Symptoms

The most common presenting symptom of LLS is lateral pain over the proximal humeral head. Presentation is often preceded by an increase in throwing activity. Pain can be severe during and after throwing exercises and can progressively worsen with continued use.

Clinical Evaluation and Physical Exam

• Inspect: Inspect the shoulder for any swelling, atrophy, and asymmetry of the bony architecture. These findings are less common but may indicate severity or may point toward a more serious cause of shoulder pain. Don’t forget to consider and rule out serious causes of joint pain, such as septic arthritis, if presented with a painful, swollen joint.
• Palpate: The most common physical exam finding in LLS is tenderness over the anterolateral proximal humeral head. Palpate the proximal humerus and biceps tendon, which will demonstrate pain in the lateral humerus over the physis.
• Range: Patients with throwing pathologies may have glenohumeral internal rotation deficiency, or GIRD, which is sometimes associated with LLS. With the arm held at 90 degrees abduction, internally and externally rotate the shoulder joint, comparing the affected arm to the unaffected arm. Patients with LLS may have pain with internal or external rotation and with abduction against resistance.
• Special Tests: The use of special tests can help narrow your differential. However, sensitivity and specificity of these tests vary and should always be correlated with imaging and the overall clinical picture.

Imaging

LLS can be diagnosed by clinical presentation alone. However, imaging may aid in diagnosis. Anteroposterior x-rays of both shoulders held in external rotation will show a widened physis in the throwing shoulder compared to the unaffected shoulder. Furthermore, the extent to which the physis is widened in comparison may be an indication of severity. Importantly, widening of the physis may be present in players who are asymptomatic. In the absence of shoulder pain, a widened physis alone does not suggest a diagnosis of LLS. Other radiographic findings include sclerosis and demineralization of the surrounding bone. Ultrasound of the affected joint may demonstrate increased hypo-echogenicity in the surrounding tissue and may be helpful in making the diagnosis. In addition, MRI may be used if other modalities are equivocal and may help identify or disambiguate LLS from other sources of shoulder pain.

Radiograph showing widening of the humeral physis with adjacent sclerosis. Diagnosis: Little League Shoulder. Photo courtesy of Dr Samir Benoudina, Radiopaedia.org, rID: 7941

Management, Prevention and Prognosis

Current evidence supports that a 2-4 month rest from throwing activities is effective management for LLS. Alternative activities that do not require repetitive shoulder use are encouraged in the interim. Most patients are able to return to throwing after prescribed rest. Return to activity should be gradual, with an increase in intensity and duration of activity over time, provided symptoms do not return. NSAIDs may be used acutely for pain, and physical therapy may aid in shortening the time for recovery. Most patients make a full recovery, and repeat radiographic studies usually show healing of the epiphysis subsequent to prescribed rest. Recurrence is common, and activity should be halted if symptoms return. Complications are rare but may include premature closure of the humeral physis, accelerated growth of the humerus, labral and pectoralis tears, humeral retroversion, and arthritis.

Studies show that players who throw for multiple teams and have an extended throwing season or those who engage in excessive daily practice are at greater risk for LLS. Little League® offers age-based guidelines for pitching and recovery time based on research published by the American Sports Medicine Institute. In addition, the presence of risk factors, such as a history of shoulder pain, variable mechanics, or GIRD, can help identify players who are at risk for developing LLS.

Summary

• Consider LLS in adolescents who report worsening pain in the proximal humerus during or after repetitive throwing activities.
• A recent increase in throwing activity may precede injury and is a pertinent history finding.
• Examine for tenderness over the lateral proximal humeral head and decreased range of motion. Swelling, weakness, atrophy, or asymmetry may also be present.
• LLS can be diagnosed clinically. However, plain films of the shoulder may show widening of the epiphysis of the throwing arm and may help in diagnosis. MRI may be useful to identify or disambiguate other injuries when plain films are equivocal. Ultrasound may also be of use.
• Treat with rest from throwing activities for 2-4 months with a gradual return to activity. NSAIDs may be used for pain and swelling. Physical therapy may aid recovery.
• Most patients experience full recovery and return to sports with proper management.
• Prevent LLS by avoiding excessive throwing and with adequate rest
• Pitfalls: Don't miss serious causes of shoulder pain.
• A widened physis can occur in patients without LLS. Correlate clinically.

Additional Reading
WikiSM.org: Humeral Head Epiphysiolysis

Associated Throwing-Related Shoulder Injuries

Table created by the authors

Resources

1. Bednar ED, Kay J, Memon M, et al. Diagnosis and Management of Little League Shoulder: A Systematic Review. Orthop J Sports Med. 2021 Jul 29;9(7):23259671211017563. PMID: 34377716; PMCID: PMC8330489.
2. Osbahr DC, Kim HJ, Dugas JR. Little League shoulder. Curr Opin Pediatr. 2010 Feb;22(1):35-40. doi: 10.1097/MOP.0b013e328334584c. PMID: 19926993.
3. Haischer MH, Howenstein J, Sabick M, et al. Torso kinematic patterns associated with throwing shoulder joint loading and ball velocity in Little League pitchers. Sports Biomech. 2021 Dec 21:1-14. doi: 10.1080/14763141.2021.2015427. Epub ahead of print. PMID: 34930092.
4. Holt JB, Stearns PH, Bastrom TP, et al. The Curse of the All-Star Team: A Single-Season Prospective Shoulder MRI Study of Little League Baseball Players. J Pediatr Orthop. 2020 Jan;40(1):e19-e24. doi: 10.1097/BPO.0000000000001391. PMID: 30994580.
5. Marshall KW. Overuse upper extremity injuries in the skeletally immature patient: beyond Little League shoulder and elbow. Semin Musculoskelet Radiol. 2014 Nov;18(5):469-77. doi: 10.1055/s-0034-1389264. Epub 2014 Oct 28. PMID: 25350825.
6. Popkin CA, Levine WN, Ahmad CS. Evaluation and management of pediatric proximal humerus fractures. J Am Acad Orthop Surg. 2015 Feb;23(2):77-86. doi: 10.5435/JAAOS-D-14-00033. PMID: 25624360.
7. Heyworth BE, Kramer DE, Martin DJ, et al. Trends in the Presentation, Management, and Outcomes of Little League Shoulder. Am J Sports Med. 2016 Jun;44(6):1431-8. doi: 10.1177/0363546516632744. Epub 2016 Mar 16. PMID: 26983458.
8. Regular Season Pitching Rules - Little League. Copyright © 2003-2022 Little League. All Rights Reserved.