2017 ISAKOS Biennial Congress ePoster #2109

 

Ultrasonographic Findings of Little Leaguer’s Shoulder in Adolescent Baseball Players

Hyung-Lae Cho, MD, Busan KOREA, REPUBLIC OF
Jung Hoei Ku, MD, Busan KOREA, REPUBLIC OF
Myung-Ji Shin, MD, Busan KOREA, REPUBLIC OF
Ki-Bong Park, MD, Ulsan KOREA, REPUBLIC OF

Department of Orthopaedic Surgery, Good Samsun Hospital, Busan, KOREA, REPUBLIC OF

FDA Status Not Applicable

Summary

Ultrasonographic Findings of Little Leaguer’s Shoulder

Abstract

Purpose

The purpose of this study is to evaluate the ultrasonographic findings of little leaguer’s shoulder among adolescent baseball players.

Materials And Methods

Forty-two (Age 11-16, mean 13.8 years, right 39, left 3) little leaguer’s shoulder patients, based on plain X ray, were examined by bilateral shoulder ultrasonography. Criteria of abnormal radiographic findings were sclerosis of proximal humeral metaphysis, partial or complete widening of proximal humeral epiphysis and physeal fragmentation. All patients had dominant shoulder pain and posterior shoulder tightness on physical examination. Longitudinal sonographic images of proximal humeral epiphysis of the dominant shoulder were compared with the contralateral nondominant shoulder. All patients were divided into groups on the basis of sonographic abnormalities and bilateral differences of physeal gap were measured in the case of significant physeal widening. Baseline variables including demographic characteristics, position played, duration of playing, pitch count and symptom duration were compared among each groups.

Results

Sonographic abnormalities of dominant shoulder were physeal irregularity (19/42, 45%), physeal fragmentation (9/42, 21%) and periosteal thickening (15/42, 36%) and physeal widening (35/42, 83%) that was the most common abnormalities. Based on sonographic findings, seven of 42 (Group A, 7%) patients had only physeal irregularity with minimal (<1 mm) physeal widening, 26 patients (Group B, 62%) had more than 1 mm physeal widening compared with nondominant shoulder. Nine patients (Group C, 21%) had both physeal widening and fragmentation. Mean physeal gaps of the dominant and nondominant shoulders in 35 patients (group B and C) were 3.4 ± 0.8 mm and 1.4 ± 0.1 mm respectively(p=0.013) and increased average physeal gap of dominant shoulder was 2.0 ± 0.8 mm. Bilateral physeal gap differences in Group B and C were 1.7 ± 0.6 mm, 3.0 ± 0.4 mm, respectively. Among three groups of patients, the duration of symptom was significant longer in group C (p=0.011), but there were no significant differences among the groups regarding other types of variables.

Conclusions

The most common ultrasonographic abnormality of little leaguer’s shoulder was widening of proximal humeral physeal in the dominant shoulder, the mean of 2.0 mm wider than nondominant shoulder. Physeal widening and fragmentation were associated with progression of the disease, but physeal irregularity was relatively early sonographic abnormalities. Ultrasonography is a useful tool to evaluate the status of proximal humeral epiphysis and can aid early diagnosis of little leaguer’s shoulder in the field.
Key words: Little leaguer shoulder, ultrasonography, proximal humeral physis