Focal Resurfacing of Humeral-Head Defects

Abstract

Traumatic shoulder instability is extremely common in athletes. It is usually due to abnormal abduction, external rotation, and extension force on the shoulder, causing it to exceed normal limits of glenohumeral motion and resulting in anterior dislocation. A characteristic anteroinferior capsulolabral injury occurs and has been deemed the essential lesion in anterior shoulder instability [1]–[3]. A posterosuperior humeral-head defect (Hill-Sachs lesion) is noted in 93% of cases [4]. This bone defect, if large enough, may contribute to failed soft tissue stabilization that occurs in 8–18% of patients [4]–[6]. Large defects lead to an articular arc mismatch that, at lesser degrees of external rotation, will engage with the anteroinferior glenoid, causing instability [7]. Treatment typically entails a combined procedure to address the soft tissue injury and bone defect. For large Hill-Sachs lesions, surgical options include nonanatomic techniques, such as the remplissage procedure [4], [8], or anatomic techniques. Purchase et al. [8] used an arthroscopic remplissage technique and had only a 7% chance of recurrent instability. Anatomic techniques include either matched humeral-head allograft or resurfacing arthroplasty with HemiCAP© (Arthrosurface, Franklin, MA, USA) [9]. Allograft transplantation for Hill-Sachs lesions has been described and yields good outcomes in most case reports [10]–[12].