The pillars of the scapula

Abstract

Total shoulder replacement has been shown to provide predictable pain relief and functional improvement in patients with glenohumeral arthritis. Loosening of the glenoid component remains the most frequent indication for revision surgery at long-term follow-up. The component most widely used is an all-polyethylene keeled or pegged design cemented to the glenoid cavity of the scapula. The glenoid is small and its cup-shaped morphology allows only a restricted site for limited fixation devices. This is particularly so in revision surgery where there are often large bony defects of the glenoid. In an anatomical study, we investigated the scapula in order to identify substantial bony pillars for better component fixation. Forty cadaveric shoulders (mean age 86, range 67-101) were dissected, the glenoids were denuded from cartilage, and the subchondral and cancellous bone was removed. Two bony pillars approaching the glenoid were consistently identified in all scapulae investigated. These pillars were outlined by three cortices and orientated to the circle formed by the rim of the inferior quadrants of the glenoid. One pillar is directed inferiorly near the margo lateralis and the other pillar is directed superiorly into the spine of the scapula. We defined these pillars in length and direction, and three-dimensionally located them in relation to the joint surface. This study demonstrated two bony pillars as important anatomical landmarks in the scapula. They were constant in presence, surgically accessible, and have not been described before. These results can be used as a guideline in the development of prosthetic designs to improve the fixation of glenoid components.

Relationship of the Medial Clavicular Head to the Manubrium in Normal and Symptomatic Degenerated Sternoclavicular Joints

“…To our knowledge, this study is the first to describe a frontal plane as a best-fitting plane on an area on the manubrium (see Appendix). This consistent area appears to represent a structural adaptation of bone to mechanical loading as has been described in other bones 12,13 . This triangular area is based on the Y-shaped area that can be seen when placing the manubrium against a bright light or in a 3D CT-reconstructed manubrium.…”

A Study of Morphology of the Glenoid Cavity

“…Though the right glenoid value was slightly more than the left, it was not statistically significant. Von Schroeder et al 8 , Coskun et al 9 and Karelse et al 10 reported the SI diameter to be 36±4mm, 36.3±3 mm and 35.9±3.6 mm respectively. All these values are higher than what was recorded in our study.…”

Morphometry and Morphology of Glenoid Cavity of Scapula

“…In the present study the average superiorinferior diameter of the right glenoid was 38.49±3.17mm and the average superior-inferior diameter of the left glenoid was38.06±3.34 mm. Von Schroeder et al [9], Coskun et al [16] and Karelse et al [12] [11] measured the SI diameter of the male and female glenoid separately. The average SI diameter of male glenoid measured by these authors was 37.5±2.2, 36.08±2.05 mm and 38.71±2.71mm respectively.…”