Study Design: Retrospective chart review.
Objective: To assess the pulmonary function and rib deformity of patients following Schollner and modified Schollner costoplasty. Little is described in the literature concerning the long term effects of costoplasty.
Methods: Retrospective analysis of patients undergoing costoplasty at our institution with a minimum of three year and a maximum of 22 years follow-up.
Subjects: 23 (20 female) patients with a primary diagnosis of late-onset idiopathic scoliosis with a rib hump deformity underwent costoplasty at age 25 (16–36). 10 had surgery on the convexity alone and 13 had additional ‘concave surgery’ (6 of these had silastic implants). 3 patients had simultaneous correction of spinal deformity and costoplasty. The remainder underwent delayed procedures (0.6–19 years) following the index operation. Harrington instrumentation was used in all patients for primary curve correction.
Outcome measures: Forced Vital Capacity (FVC) – including % normal expected for age and rib hump (clinically and from radiographs) were measured pre and post-operatively at each attendance to assess the outcome of the procedure.
Results: The mean follow up was 10.7 years (3–22). Average reduction in rib hump was 33 mm at 6 months and 25 mm at the latest follow-up. There was no significant difference in the pre-operative and long-term FVC (p=0.4, paired t-test), although 6 months post-operatively there was a significant reduction in FVC (p=0.03, paired t-test). Subgroup analysis (convex only, convex/concave without silastic implant, convex/concave with silastic implant) revealed a similar pattern for rib hump correction and maintenance of FVC in all 3 groups at latest follow-up. However for patients undergoing convex surgery alone, the difference between FVC at 6 months and at latest follow-up was significant (p=0.01, paired t-test).
Conclusions: Rib hump correction and lung function (even accounting for age) are preserved in the long term following costoplasty. This study does not show any benefit of additional surgery on the concavity of the curve in reducing the rib hump on the convexity or on the FVC.
