Residual inferior glenohumeral instability after arthroscopic Bankart repair: radiological evaluation and functional...

Treatment of anteroinferior shoulder instability by arthroscopy must restore stability while preserving joint motion. Inferior glenohumeral ligament (IGHL) laxity is an important parameter in the pathomechanism of this condition. The goals of this study is to use the Shoulder HyperAbduction Test (SHART) radiological test to quantify the tension in the IGHL following surgery and look for an eventual correlation between ligament tightening and joint motion.

This was a single-center, retrospective study that included patients with unilateral anteroinferior instability who were treated with an arthroscopic Bankart repair between September 2004 and December 2005. These patients did not experience any recurrence within a follow-up period of at least 2 years. Twenty-three patients were followed-up. This series included 16 men and seven women with an average age of 29.7±12 years. The average Instability Severity Index Score (ISIS) was 1.7±1.3 (from 0 to 3). The main outcome measures were the bilateral SHART test at the last follow-up visit and bilateral joint range of motion, before surgery and at the last follow-up.

The follow-up was 3.3 years on average. The average SHART on the operated side (116.9±11.7°) was lower than the healthy side (121.9±9.6°), P=0.01. A difference of less than 4° was statistically related to loss of external rotation, with an odds ratio of 16, P=0.03. At the last follow-up, the average Walch-Duplay functional score was 72.4±13.8/100 and the Rowe score 90.2±11.6/100.

It is difficult to achieve a perfect compromise between shoulder stability and joint motion. Progress in arthroscopy technique has led to a greater demand for the tightening of capsulo-labral and ligament structures. An arthroscopic Bankart repair provides IGHL tightening that is quantifiable with the SHART. External rotation is reduced when excessive tightening is made.