Medizinische Universität Graz - Research portal
Selected Publication:
Siwetz, M.
Subscapularis anatomy in the context of shoulder surgery
Humanmedizin; [ Diplomarbeit ] Medizinische Universität Graz; 2023. pp.
- Authors Med Uni Graz:
- Advisor:
- Hammer Niels
- Altmetrics:
- Abstract:
- Background: The subscapularis muscle forms part of the rotator cuff and is located anterior to the shoulder joint. When approaching the shoulder joint anteriorly, its supplying nerves are at risk of iatrogenic injury, which may cause postoperative complications. Purpose: The aim of this study was to describe a maximal sized nerve free zone in which a subscapularis-split can be performed. Materials and Methods: In 84 anatomical specimens, the distance from the myotendinous junction of subscapularis muscle to the entrance points of the subscapular nerves was measured with the arm abducted 60° and externally rotated. Further measurements were taken in 16 subsamples with the arm abducted 60° and rotated neutrally, abducted 60° and rotated internally as well as abducted 90° and rotated externally. The positions of the entrance points were described with statistical parameters and compared for the different sides, sexes, and joint positions. Results: The distance averaged 42.9 mm (range 24 – 64 mm) for the upper subscapular nerve and 37.9 mm (range 23 – 59 mm) for the lower subscapular nerve with the arm rotated externally and abducted 60°, respectively. In the 16 subsamples, it was shown that internal rotation decreased the distance to 33.4 mm (range 24 – 49 mm) and 30.5 mm (range 15 – 43 mm), respectively, while maximal external rotation and 90° abduction increased the distance up to 48.1 mm (range 30 – 64 mm) and 41.5 mm (range 27 – 56 mm). Conclusion: A “safe zone” of 20 mm based on the minimum distances medial to the myotendinous junction with the arm rotated externally, seems to provide sufficient protection from nerve injury during surgery.