Unusual morphology of scapulae: incidence and dimensions of ossified ligaments and supraspinous bony tunnels for clinical consideration

<p><b>INTRODUCTION</b>Knowledge of morphological variations of the suprascapular region is important in the management of entrapment neuropathy and interventional procedures. The objective of this study was to collect data on the morphological features and dimensions of ossified ligaments and unusual bony tunnels of scapulae from a North Indian population.</p><p><b>METHODS</b>A total of 268 adult human scapulae of unknown gender were obtained from the bone bank of the Department of Anatomy, Dayanand Medical College and Hospital, Ludhiana, Punjab, India. The scapulae were evaluated for the incidence of ossified superior transverse scapular ligaments (STSLs), ossified inferior transverse scapular ligaments (ITSLs) and bony tunnels (i.e. the bony canal between the suprascapular notch and spinoglenoid notch), found along the course of the suprascapular nerve (SSN). The dimensions of these structures were measured and noted down. Ossified STSLs were classified based on their shape (i.e. fan- or band-shaped) and the dimensions of the ossified suprascapular openings (SSOs) were measured.</p><p><b>RESULTS</b>Ossified STSLs were present in 26 (9.7%) scapulae. Among the 26 scapulae, 16 (61.5%) were fan-shaped (mean area of SSO 16.6 mm(2)) and 10 (38.5%) were band-shaped (mean area of SSO 34.2 mm(2)). Bony tunnels were observed in 2 (0.75%) specimens, while an ossified ITSL was observed in 1 (0.37%) specimen.</p><p><b>CONCLUSION</b>The data obtained in the present study augments the reference literature for SSN decompression and the existing anatomical databases, especially those on Indian populations. This data is useful to clinicians, radiologists and orthopaedic surgeons.</p>

The inferior transverse scapular ligament in Thais.

Eighty-four shoulders of cadavers were dissected to determine the prevalence of the inferior transverse scapular (Spinoglenoid) ligament. Three types of the structures, forming an arch above the suprascapular nerve ad vessels at spinoglenoid notch, were classified in this study. Type I, the inferior transverse scapular fascia, was found in 45 cases (53.6 percent). Type II, the inferior transverse scapular membrane, was present in 30 cases (35.7 percent). This membrane was formed by bands of fascia distinct from the surrounding tissues. Type III, the inferior transverse scapular ligament, was present in 9 cases (10.7 percent). The ligament extended from the lateral border of the spine of the scapula to the margin of the glenoid cavity. Type I was the most common and type III was the least. Type I and type Ii were not true ligament. The study can serve as a reference to the inferior transverse scapular ligament in Thai and remind the neurologist or neurosurgeon that suprascapular nerve compression may result from lesions of the inferior transverse scapular ligament.