The glenoid notch and its relation to the shape of the glenoid cavity of the scapula

Abstract

The prevalence of a notch in the anterior margin of the glenoid cavity of 236 scapulae (118 female, 118 male) was investigated. The notch was found in 129 scapulae (55 %) and gave rise to a pear-shaped cavity. In 107 scapulae (45 %) the notch was absent, the shape of the cavity being oval. No sex difference was found in the prevalence of the notch. If a distinct notch exists, the glenoid labrum is not attached to bone at the notch and is therefore liable to be sheared off (Bankart lesion).Key words : Skeletal anatomy ; Bankart lesions. Most of the standard anatomical textbooks describe the shape of the glenoid cavity as pear-shaped, round, oval or having an inverted comma-shape. During our examination concerning the sex dimorphism of the glenoid cavity (Prescher & Klu$ mpen, 1994, 1995 we observed that all these descriptions may be accurate, depending on the presence or absence of a distinct glenoid notch. According to Fick (1904) the glenoid notch is located at the anterior margin of the glenoid cavity. The notch is situated somewhat above the middle of the anterior margin of the cavity and can be very prominent (Fig. 1 a), very shallow ( Fig. 1 b) or absent (Fig. 1 c). Von Langer (1882) termed the glenoid notch the incisura acetabuli. It is only briefly mentioned in the paper by Huber (1991). It is remarkable that the notch is rarely mentioned in the standard anatomical textbooks although it is noted, for example, by Rouvie' re (1967), Gardner et al. (1969), Woodburne & Burkel (1988) and Grant (1989). In the French literature (Rouvie' re, 1967) it is designated as ' e! nchancrure gle! noidienne '. In addition, the notch is mentioned by Frazer (1958), who stated that the position of the notch indicates the line of the junction between the ' coracoid ' and the ' scapular ' parts of the glenoid cavity. The present study was undertaken to provide information about the prevalence of the glenoid notch, how this notch will affect the shape of the glenoid cavity, and whether a sex or side preference for the presence of the notch exists, and also to examine the relation of the glenoid notch to the glenoid labrum.   For this investigation 236 unselected scapulae (118 female, 118 male) collected between 1985 and 1996 at the Anatomical Institute of the Rheinisch-Westfa$ lischen Technischen Hochschule (RWTH) in Aachen, were examined. These scapulae came exclusively from German individuals in the area of Aachen. The age and sex of each pair of scapulae were known. Contour drawings of the articular facet were produced by hand with the aid of paper stencils (Zweckform selfadhesive labels) (Prescher & Klu$ mpen, 1995) which could then be examined qualitatively for the occurrence of the glenoid notch. Scapulae with clearly recognisable degenerative, metastatic or traumatic changes involving the glenoid cavity were not included. We also examined 30 unmacerated fixed (4 % buffered formalin) or unfixed

Morphometry and Morphology of Glenoid Cavity of Scapula

“…Mamatha et al [6] had found it to be 80% on the right side and 76% on the left side . Prescher and Klumpen [3] had observed it to be 55% which was lesser than in the current study. In the current study, oval glenoids comprised only of 38.89% on the right side and 34.21% on the left side.…”

“…As compared to Mamatha et al [6] who found it to be 20% on the right side and 24% on the left side . Prescher and Kulmpen [3]observed that 45% of the glenoids were oval shaped . Coskun N et al [16] studied 90 scapulae and found that, in 72% of the specimens, the glenoid notches of the scapulae was absent or oval shaped, whereas in 28% the notch was well expressed and the glenoid cavity was pear shaped.…”

“…Glenoid cavity surface is covered with hyaline cartilage in the fresh state and its slightly raised margins give attachment to a fibrocartilaginous structure the glenoid labrum which deepens the cavity [2]. Due to presence of this glenoid notch, various shapes of glenoid cavity are found like pear-shaped, oval or inverted comma shaped [3,4]. The glenohumeral joint is most unstable joint in the body due to its performance of a wide range of movements.…”

Study of Glenoid Cavity of Human Scapula and Its Clinical Importance

“…As compared to Mamatha et al [12] who found it to be 20% on the right side and 24% on the left side. Prescher and Kulmpen [3] observed that 45% of the glenoids were oval shaped Coskun N et al [10] studied 90 scapulae and found that, in 72% of the specimens, the glenoid notches of the scapulae were absent or oval shaped, whereas in 28% the notch was well expressed and the glenoid cavity was pear shaped. These findings were higher than that of the present study.…”

“…The glenoid rim presents a notch in its upper and front part [2]. Due to presence of this glenoid notch, various shapes of glenoid cavity are found like pearshaped, oval or inverted comma shaped [3,4]. Shoulder joint is frequently dislocated inferiorly due to having less support in that region of the joint.…”