Review Question - QID 219815

This patient presents with several risk factors of recurrent instability and would most appropriately be managed with a coracoid transfer to prevent recurrence (Answer 3).

Traumatic anterior shoulder instability is the most common form of shoulder instability and requires consideration of the entire clinical presentation. This patient presents with recurrent instability and glenoid bone loss of approximately 24%. Although the exact degree of bone loss is debated, a defect of 20-25% is considered "critical bone loss" and is believed to confer a high degree of instability. A Hill-Sachs lesion of greater than 84% of the glenoid width is considered off-track and clinically relevant. If arthroscopic Bankart repair is done to address instability, an off-track lesion can be managed with remplissage. This patient is also under the age of 20, participates in competitive sports, and has glenoid contour loss on his original AP x-ray. The instability severity score is another clinical tool that can help guide treatment. Due to the patient’s multiple risk factors, he has a recurrence rate of greater than 70% with arthroscopic stabilization alone. The most appropriate treatment course is a coracoid transfer to address the patient's chronic glenoid bone loss.

Horinek et al. published the results of a multi-center retrospective study of 258 patients with 2-year outcomes following arthroscopic Bankart repair with remplissage or open coracoid transfer for the treatment of shoulder instability. The authors evaluated patient-reported outcomes, return to the same level of sport, patient satisfaction, recurrence, and surgical complications. The mean preoperative glenoid bone loss was 7.6% in the coracoid transfer group and 12.3% in the arthroscopic group. The authors concluded that arthroscopic Bankart repair with remplissage resulted in 2-year functional outcomes that were as good or superior to primary Latarjet with higher rates of return to sport, fewer complications, and lower recurrence rates.

MacDonald et al. published the results of a randomized controlled trial of 108 patients with recurrent anterior shoulder instability in the presence of an off-track Hill-Sachs defect. The patients were randomized to arthroscopic Bankart repair with or without remplissage. They were followed for 24 months. The rates of instability and revision surgery were found to be higher in the no remplissage group. The authors concluded that the addition of the remplissage procedure significantly lowers the rates of recurrent instability.

Piasecki et al published a review article on the appropriate management of glenoid bone deficiency with anterior shoulder instability. The authors discuss glenoid bone loss of increasing percentage. As bone loss approaches 20-25% the authors recommend addressing the deficiency with a bony procedure. They report on a study that had 89% recurrent instability in contact athletes when a soft tissue on the repair was used to address deficits of approximately 25%. The authors recommend a bony Bankart repair if the bone is still viable. If there is chronic bone loss they recommend bony augmentation of the glenoid.

Figure 1 is an AP radiograph of a shoulder showing loss of glenoid contour, suggesting a bony Bankart lesion of the anterior glenoid. Figure 2 shows a CT sagittal cut of the shoulder measuring 6.9 mm of glenoid loss out of the original 28.3 mm, which calculates to a glenoid bone loss of 24.4%.

Incorrect Answers:
Answer 1: Physical therapy will not address the biomechanical instability associated with glenoid bone loss.
Answer 2: Due to the patient’s age, sport involvement, glenoid bone loss, and recurrent instability, an arthroscopic soft tissue procedure is not recommended.
Answer 4: An open capsular shift will not address the glenoid bone loss.
Answer 5: Humeral head allograft is reserved for Hill-Sachs lesions that are greater than 40% of the humeral head. Humeral head allograft will also not address the glenoid bone loss.