The Glenoid Fossa's Morphometric Investigation and Its Clinical Implications

Background The inconsistent morphology of the scapula is based on variable dimensions of its glenoid cavity, in addition to its broadened and truncated lateral angle. Its variable shapes are attributed to the spinoglenoid cavity (superior and posterior aspect of the scapula), which appears oval, inverted comma-shaped, and piriform (pear-shaped). Traumatic conditions often lead to glenoid dislocation/fracture. The precise administration of total shoulder arthroplasty with glenoid component adjustment warrants a comprehensive knowledge of scapular morphology. This study aims to assess the glenoid cavity/scapula shapes (anthropometric assessment) among individuals located in Odisha, India.  Methods This cross-sectional analysis was undertaken on 74 left-sided and 70 right-sided, dry, and undeteriorated scapulae of human adult specimens obtained from the anatomy department irrespective of their gender and age.  Results The glenoid cavity was most commonly inverted comma-shaped (34.02%) and pear-shaped (48.61%) while 17.36% of scapulae had oval-shaped glenoid cavities. The mean scapular breadth and length dimensions were 98.12±7.87mm and 135.76±12.85mm, respectively. Statistically insignificant bilateral variations were observed between the glenoid cavity index (mean value: 68.44±7.98%), glenoid diameter-2 (anteroposterior; mean value: 16.17±2.24mm), glenoid diameter-1 (anteroposterior; mean value: 22.67±1.53mm), and glenoid diameter (superoinferior; mean value: 36.03±2.15mm).  Conclusion The size and shape of the glenoid cavity are directly associated with the dislocation of the shoulder joint and may disturb the results of total shoulder arthroplasty and rotator cuff surgeries. The current study analyzed the morphological types and diameters of the glenoid cavity in the scapulae to improve efficiency and lessen the failure proportions in shoulder arthroplasty. The study shows that morphological measurement of scapulae plays a vital role in the effective maintenance of posture and shoulder functions.

Morphological classification and measurement of the glenoid cavity using three-dimensional reconstruction in a Chinese population

BACKGROUND

The purpose of this study was to examine the various shapes and record the morphometric data of the glenoid cavity in a Chinese population.

MATERIALS AND METHODS

A total of 501 scapulae, 247 left and 254 right, were analyzed. We classified the shape of the glenoid cavity as type Ⅰ (pear-shaped), type Ⅱ (oval-shaped), type Ⅲ (teardrop-shaped), type Ⅳ (calabash-shaped) or type Ⅴ (inverted comma-shaped). Four defined parameters, the superior-inferior glenoid diameter (AB), upper anterior-posterior glenoid diameter (CD), lower anterior-posterior glenoid diameter (EF) and glenoid index (GI), were measured, and five shapes were classified via three-dimensional reconstruction.

RESULTS

The mean AB, CD, EF and GI values of the glenoid were 3.51±0.41 cm, 1.95±0.28 cm, 2.60±0.34 cm, and 1.35±0.12 cm, respectively. The AB value of type Ⅱ glenoid cavities was significantly smaller than that of type Ⅰ and Ⅲ glenoid cavities (P<0.05), but the GI value of type Ⅱ glenoid cavities was larger than that of type Ⅲ cavities (P<0.05). The CD value showed a difference between type Ⅰ and type Ⅲ glenoid cavities (P<0.05). For the EF parameter, the values of type Ⅲ glenoid cavities were significantly larger than those of type Ⅰ and Ⅱ glenoid cavities (P<0.05).

CONCLUSIONS

Measuring and observing the variety of shapes and sizes of the glenoid cavity in Chinese people is conducive to for better understand its morphological features. This information can also guide surgeons in the design and selection of suitable prostheses for total shoulder arthroplasty in the Chinese population in order to reduce postoperative complications.