Surgical Management of Thumb Deformity in Children With Hemiplegic-type Cerebral Palsy

Background: Evidence-based clinical decision-making for the surgical management of thumb deformities in children with cerebral palsy is difficult, primarily because of a lack of consensus with respect to assessment of thumb alignment and function. We have used the Shriners Hospital Upper Extremity Evaluation, a validated assessment tool, to determine the outcome after thumb reconstruction surgery in these children. The goals of this study were to determine the relationship between static and dynamic assessments of the thumb before surgery, the outcomes with respect to static and dynamic alignments of the thumb after soft tissue and skeletal surgery, and the relationship between preoperative spontaneous functional use of the involved extremity (indicative of the magnitude of neurologic impairment) and the change in thumb dynamic alignment after surgery. Methods: A retrospective case series was performed, consisting of 33 children with hemiplegic-type cerebral palsy who had undergone surgical reconstruction of the thumb between 1998 and 2006. All children had preoperative and postoperative Shriners Hospital Upper Extremity Evaluation analyses performed (mean time to follow-up was 2 y and 2 mo). Static modified House scale of thumb alignment, dynamic thumb positional analysis, and the spontaneous functional use of the involved extremity were compared and contrasted. Results: Dynamic thumb alignment was significantly worse than static thumb alignment (P = 0.0005). Comparable improvements were achieved in both static and dynamic thumb alignment after surgical thumb reconstruction (P = 0.6242). Optimal outcome was achieved more frequently in the static alignment (82% of cases) than in the dynamic alignment (61% of cases). There was poor correlation between the spontaneous use of the involved extremity before surgery and the changes in thumb dynamic alignment after surgery (Pearson correlation coefficient 0.1554, P = 0.39). Conclusions: Static thumb alignment is not a good predictor of dynamic function, and interventions designed to improve function should focus on the assessment of dynamic thumb alignment. Improvements in both static and dynamic alignment of the thumb are possible after reconstructive surgery (consisting of muscle release, tendon transfer, and skeletal stabilization), regardless of the degree or density of underlying neurologic impairment.