The superomedial bare area of the costal scapula surface: a possible cause of snapping scapula syndrome

Dr Youn Research Articles

A Technical Trick

Arthroscopic Decompression

Biceps Rerouting

Functional and Radiologic Outcomes

Comorbidity Effects in Shoulder Manipulation

Retracted Rotator Cuff Tear

The Scissors Sign

Rotator Cuff Repairs

Medialized vs. Lateralized Humeral Implant

Posterior Compression Test

A Comparative Animal Model Study

Functional Outcomes of Reverse Shoulder

The Superomedial Bare Area of the Costal Scapula Surface

The superomedial bare area of the costal scapula surface: a possible cause of snapping scapula syndrome

Abstract

Purpose: Scapulothoracic bursitis is a painful condition of the scapulothoracic articulation, which may be caused by various pathological anatomical associations. We have arthroscopically observed a constant bare area of bone on the costal scapula surface in patients with scapulothoracic bursitis, contradictory to traditional anatomical reports of scapular muscle relations. We undertook a cadaveric study to further define this anatomical feature.

Methods: Twelve cadaveric shoulders were dissected. The costal surface of the scapula was systematically examined for the presence of a superomedial bare area in each shoulder by three independent clinicians, with dimensions measured using digital calipers.

Results: In all shoulders, there was a clearly defined bare area of bone on the superomedial aspect of the costal surface of the scapula between the serratus anterior insertion and subscapularis origin. The bare area was typically crescenteric in shape, with variable length (mean 22.3 ± 6.0 mm) and width (10.8 ± 2.8 mm). The bare area length (p = 0.043) and width (p = 0.033) were significantly greater in female shoulders compared to male shoulders.

Conclusions: We have established the presence of the superomedial bare area of the costal scapula surface. With an absence of overlying subscapularis muscle, this bare area carries the potential for scapulothoracic impingement, and should be considered as a possible aetiological factor in all patients presenting with scapulothoracic bursitis.