Bone Loss Associated with Instability
Authors: Boileau et al
References: Practical Arthroscopy, September 2004
Boileau reported on his series of 91 patients that had bony defects on either the humeral or glenoid side were associated with higher recurrence rates. Poor capsular quality, such as seen in the MDI patient, is also associated with increased failure of arthroscopic instability repairs. The amount of glenoid loss can be measured by CT scan or by the arthroscopic measurement technique of Burkhart to detect the inverted pear glenoid. Cases with >25% loss of anterior glenoid are a contra-indication to an arthroscopic procedure. In this situation, Burkhart favours an open Latarjet procedure.
Latarjet Procedure: Burkhart and DeBeer had reported in the past that if there was significant bone loss to the anterior glenoid, resulting in the pear-shaped, or the banana-shaped glenoid; the recurrence rate is 87% compared to 6.5% failure of instability repair with no bone loss. The Latarjet procedure uses the coracoid to replace the anterior bone loss. This is not just the tip of the coracoid, i.e. the Bristow procedure, but a long piece of bone, 2-3cm in length that lengthens the glenoid articular arc.
The results of the Latarjet procedure in 102 patients were a 3.9% recurrence rate, but with some reduced external rotation.
Can the Latarjet be done as an arthroscopic procedure? Taverna from Italy described an arthroscopic procedure that places a bone graft to the anterior glenoid using a large anterior cannula. The six cases were all done in a lab on cadavers to perfect the procedure. The graft is held in place with screws and a normal suture anchor repair is done on the anterior edge of the glenoid, leaving the bone graft extra-articular.