Arthroscopic release and latissimus dorsi transfer for shoulder internal rotation contractures and glenohumeral deformity secondary to brachial plexus birth palsy.

BACKGROUND: Internal rotation contractures due to external rotation weakness secondary to brachial plexus birth palsy frequently lead to glenohumeral deformity and impaired shoulder function. Our surgical approach to treat these contractures relies on arthroscopic release for young children (less than three years old) and combines arthroscopic release with latissimus dorsi transfer for older children. We report the results for the first thirty-three children followed for a minimum of two years after such treatment.
METHODS: Nineteen children with a mean age of 1.5 years (all younger than three years of age) underwent arthroscopic contracture release as the only primary procedure, and fourteen children with a mean age of 6.7 were also treated with a latissimus dorsi transfer. Passive external rotation with the arm at the side and passive and active elevation were measured for all patients preoperatively. Passive and active external rotation, internal rotation, and elevation were measured for all patients postoperatively. Magnetic resonance imaging was performed preoperatively and postoperatively to evaluate the status of the glenohumeral joint.
RESULTS: Preoperative passive external rotation averaged -2 degrees for the children who underwent arthroscopic contracture release only and -24 degrees for those who also were treated with a latissimus dorsi transfer. Arthroscopic release achieved a marked increase in passive external rotation and a centered position of the glenohumeral joint at the time of surgery in all but the oldest child in the series, who had severe deformity. The contracture recurred in four of the younger children who had an isolated release, and this was treated with a repeat arthroscopic release and a secondary latissimus dorsi transfer. None of the children who had a primary latissimus dorsi transfer had recurrence of the contracture. At the time of follow-up, the mean passive external rotation was increased by 67 degrees (p < 0.005) in the fifteen children with a successful arthroscopic release, 81 degrees (p < 0.005) in those treated with a primary latissimus dorsi transfer, and 78 degrees in the four patients who were treated with a late latissimus dorsi transfer because the isolated arthroscopic release failed. The mean active elevation increased 12 degrees , 3 degrees , and 10 degrees , respectively, in the three groups. Internal rotation was not measured consistently preoperatively, but when it had been it was found to have decreased substantially postoperatively. Magnetic resonance imaging performed prior to the surgery showed a pseudoglenoid deformity in eighteen of the children. At two years, magnetic resonance images were available for fifteen of those children, and twelve of the images showed marked remodeling of the deformity.
CONCLUSIONS: In children who are younger than three years of age, arthroscopic release effectively restores nearly normal passive external rotation and a centered glenohumeral joint at the time of surgery. In most of these children, external rotation strength is sufficient to maintain this range of motion and to improve glenoid development when preoperative deformity was present. The addition of a latissimus dorsi transfer in older children predictably results in similar improvements. Gains in active elevation are minimal. All children have a loss of internal rotation, which is moderate in most of them but is severe in some.