Abstract
Introduction: Analysis of location of central peg and the fours screws of the glenoid component in inverted shoulder prostheses.
Materials and methods: 34 inverted prostheses. Mean age 74.10. 33 women, 1 man. Preoperative CT: glenoid version, presence and size of bone spurs. Postoperative CT: location of central peg and 4 screws.
Results: 27 retroverted glenoids (mean 6.5°), 7 anteverted glenoids (mean 5.3°); anterior bone spur in 17 cases, posterior in 12. In 52% of the cases the central peg was inside the glenoid; in 33% the anterior part was outside and in 14% the posterior part. If the anterior part of the central peg was outside, 85% was due to retroverted glenoids (mean 8.33°). If the posterior part was outside, 66% of these were due to anteverted glenoids (mean 9.5°). Lower inside screw in the scapula in 38% of cases, 3/4 inside in 19%, 2/4 in 23% and 1/4 in 19%. Upper screw: 47%, 23% 19% and 9%, respectively. Anterior screw: 66%, 23% and 9%, respectively. Posterior screw: 38%, 42%, 14% and 4%, respectively.
Conclusions:
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- Lower screw completely within the lateral part of the scapula with less coverage by upper screw.
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- Anterior extrusion of the central peg correlated with more retroverted glenoids and posterior extrusion with very anteverted glenoids.
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- No correlation between presence of anterior and posterior bone spurs and the position of the peg or the screws.
The abstracts were prepared by Dr. E. Carlos Rodríguez-Merchán, Editor-in-Chief, Spanish Journal of Orthopaedics and Traumatology (Revista de Ortopedia y Traumatología). Correspondence should be addressed to him at: Sociedad Española de Cirugía Ortopédica y Traumatología (SECOT), Calle Fernández de los Ríos 108, 28015-Madrid, Spain
