SHOULDER ARTHRODESIS IN BRAQUIAL PLEXUS PALSY – WHAT’S THE OPTIMAL POSITION?

Abstract

Background: Braquial plexus injuries are a major indication for shoulder arthrodesis today. Numerous investigations have addressed the optimal position of the extremity for shoulder arthrodesis, and there are still numerous opinions on the ideal position. The present consensus appears to favor less abduction and forward flexion and more internal rotation.

Purposes: Our main goal is to determine the most favorable position for arthrodesis regarding upper limb function and prevalence of periscapular pain. Secondarily we describe the fusion and complications rate as well as patient satisfaction.

Materials and Methods: Between 1997 and 2008 the authors performed a total of 19 shoulder arthrodesis using a pelvic reconstruction plate in patients with braquial plexus injuries. Six were lost to follow-up leaving a total of 11 men and two women with a mean age of 46 years available for review. At a mean follow-up of 101 months [13–149] patients were evaluated clinically using predetermined functional parameters (hand-to-mouth, brachiothoracic grip, etc) and the visual analog pain scale. DASH score and radiological studies were also performed. Three patients that presented no active elbow flexion were excluded of the functional results analysis.

Results: The mean fusion position found was 20° abduction, 32° forward flexion and 44° internal rotation. Abduction ≥ 25° relates to better function as judged by a better hand-to-mouth and brachiothoracic grip ratio as well as a better DASH score (38.8 vs. 45.4) but is also unfortunately related to higher periscapular pain prevalence (VAS pain 3.75 vs. 1.38). Forward flexion ≤ 30° also relates to slightly higher periscapular pain prevalence (VAS pain 2.7 vs. 1.7) and a better DASH score (39.5 vs. 47.7). Exaggerated internal rotation seems to have a negative influence on the functional outcome. Although relating to a surprisingly better DASH score (39.7 vs. 44.9), none of the three patients presenting with internal rotation over 45° was able to reach the mouth with his/her hand. Fusion was obtained in 12 patients. Major complications included one pseudarthrosis, one malpositioning of the extremity that forced a revision surgery to increase internal rotation and one humeral shaft fracture treated conservatively. All but one patient (including those with no active elbow flexion) were satisfied/very satisfied with the final outcome.

Discussion: Our results suggest abduction around 25° and forward flexion of no more than 30° are needed. Higher abduction and lower forward flexion values although relating to better function do so at the expense of more periscapular pain. We agree with the present trend towards increasing internal rotation but found that it should not exceed 45°.