What Range of Motion is Achieved 5 Years After External Rotationplasty of the Shoulder in Infants with an Obstetric Brachial Plexus Injury?
Authors: Sarac Cigdem , Amghar Hassan , Nieuwenhuijse Marc J. , Nagels Jochem , Buitenhuis Sonja M. , Wolterbeek Ron , Nelissen Rob G. H. H. 
Published: October 2019

Abstract

Background
Obstetric brachial plexus injuries result from traction injuries during delivery, and 30% of these children have persisting functional limitations related to an external rotation deficit of the shoulder. Little is known about the long-term effect of soft-tissue procedures of the shoulder in patients with obstetric brachial plexus injuries.

Questions/purposes
(1) After soft-tissue release for patients with passive external rotation less than 20° and age younger than 2 years and for patients older than 2 years with good external rotation strength, what are the improvements in passive external rotation and abduction arcs at 1 and 5 years? (2) For patients who underwent staged tendon transfer after soft-tissue release, what are the improvements in active external rotation and abduction arcs at 1 and 5 years? (3) For patients with passive external rotation less than 20° and no active external rotation, what are the improvements in active external rotation and abduction arcs at 1 and 5 years?

Methods
This was a retrospective analysis of a longitudinally maintained institutional database. Between 1996 and 2009, 149 children underwent a soft-tissue procedure of the shoulder for an internal rotation contracture. The inclusion criteria were treatment with an internal contracture release and/or tendon transfer, a maximum age of 18 years at the time of surgery, and a minimum follow-up period of 2 years. Six patients were older than 18 years at the time of surgery and 31 children were seen at our clinic until 1 year postoperatively, but because they had good clinical results and lived far away from our center, these children were discharged to physical therapists in their hometown for annual follow-up. Thus, 112 children (59 boys) were available for analysis. Patients with passive external rotation less than 20° and age younger than 2 years and patients older than 2 years with good external rotation strength received soft-tissue release only (n = 37). Of these patients, 17 children did not have adequate active external rotation, and second-stage tendon transfer surgery was performed. For patients with passive external rotation less than 20° with no active external rotation, single-stage contracture release with tendon transfer was performed (n = 68). When no contracture was present (greater than 20° of external rotation) but the patient had an active deficit (n = 7), tendon transfer alone was performed; this group was not analyzed. A functional assessment of the shoulder was performed preoperatively and postoperatively at 6 weeks, 3 months, and annually thereafter and included abduction, external rotation in adduction and abduction, and the Mallet scale.

Results
Internal contracture release resulted in an improvement in passive external rotation in adduction and abduction of 29° (95% confidence interval, 21 to 38; p < 0.001) and 17° (95% CI, 10 to 24; p < 0.001) at 1 year of follow-up and 25° (95% CI, 15-35; p < 0.001) and 15° (95% CI, 7 to 24; p = 0.001) at 5 years. Because of insufficient strength of the external rotators after release, 46% of the children (17 of 37) underwent an additional tendon transfer for active external rotation, resulting in an improvement in active external rotation in adduction and abduction at each successive follow-up visit. Patients with staged transfers had improved active function; improvements in active external rotation in adduction and abduction were 49° (95% CI, 28 to 69; p < 0.05) and 45° (95% CI, 11 to 79; p < 0.001) at 1 year of follow-up and 38° (95% CI, 19 to 58; p < 0.05) and 23° (95% CI, -8 to 55; p < 0.001) at 5 years. In patients starting with less than 20° of passive external rotation and no active external rotation, after single-stage contracture release and tendon transfer, active ROM was improved. Active external rotation in adduction and abduction were 75° (95% CI, 66 to 84; p < 0.001) and 50° (95% CI, 43 to 57; p < 0.001) at 1 year of follow-up and 65° (95% CI, 50 to 79; p < 0.001) and 40° (95% CI, 28 to 52; p < 0.001) at 5 years.

Conclusion
Young children with obstetric brachial plexus injuries who have internal rotation contractures may benefit from soft-tissue release. When active external rotation is lacking, soft-tissue release combined with tendon transfer improved active external rotation in this small series. Future studies on the degree of glenohumeral deformities and functional outcome might give more insight into the level of increase in external rotation.

Level of Evidence
Level III, therapeutic study.