Defining shoulder function and dysplasia in patients with longitudinal deficiencies of the upper limb

Abstract

Phenotypic differences and functional limitations in children with congenital radial and ulnar longitudinal deficiencies (RLD/ULD) are well understood for the forearm and hand. However, anatomical features of shoulder elements in these pathologies have only been scarcely reported. Moreover, shoulder function has not been assessed in this patient population. Therefore, we aimed to define radiologic features and shoulder function of these patients at a large tertiary referral center. We prospectively enrolled all patients with RLD and ULD (minimum age: 7 years) for this study. Eighteen patients (12 RLD, 6 ULD) with a mean age of 17.9 years (range, 8.5-32.5) were evaluated using clinical examination (shoulder motion and stability), patient-reported outcome measures (Visual Analogue Scale [VAS], Pediatric/Adolescent Shoulder Survey [PASS], Pediatric Outcomes Data Collection Instrument [PODCI]), and radiologic grading of shoulder dysplasia (including length and width discrepancy of the humerus, glenoid dysplasia in the anteroposterior and axial view [Waters classification], and scapular and acromioclavicular dysplasia assessment). Descriptive statistics and Spearman correlation analyses were performed. Despite five (28%) cases having anterioposterior shoulder instability and five (28%) cases with decreased motion, outcome scores indicated an overall excellent function of the shoulder girdle, with mean VAS of 0.3 (range, 0-5), mean PASS of 97 (range, 75-100), and mean PODCI Global Functioning Scale of 93 (range, 76-100). The humerus was, on average, 15 mm shorter (range, 0-75), and metaphyseal and diaphyseal diameters both reached 94% of the contralateral side. Glenoid dysplasia was detected in nine (50%) cases, with increased retroversion evident in 10 (56%) cases. However, scapular (n=2) and acromioclavicular (n=1) dysplasia were rare. Based on radiographic findings, a radiologic classification system for dysplasia types IA, IB, and II was developed. Adolescent and adult patients with longitudinal deficiencies exhibit various mild-to-severe radiologic abnormalities around the shoulder girdle. Nevertheless, these findings did not seem to negatively affect shoulder function as the overall outcome scores were excellent.