COMPARISON OF PEDICLE SCREW FIXATION WITH HYBRID SUBLAMINAR WIRING INSTRUMENTATION FOR CORRECTION OF SPINAL DEFORMITY IN PATIENTS WITH CEREBRAL PALSY

Abstract

Introduction: We have compared the results of pedicle screw (PS) construct only with a hybrid sublaminar wire and pedicle screw construct (HS) in a matched cohort of CP patients, to establish which technique is superior in view of deformity correction and its maintenance.

Methods: 22 male and 14 female CP patients with average age of 16 years (range 8–25 years) underwent surgical correction for spinal deformity. Indications for surgery included loss of sitting balance, progression of spinal deformity, pelvic obliquity and back pain. Group 1 (18 patients) had PS construct only and Group 2 (18 patients) had HS constructs. 32 patients (90%) required sacral fixation. 5 patients in Group 2 required anterior release. All patients had a minimum follow-up of 2 years (range 2–13 years). Clinical and radiographic analyses were performed in both groups.

Results: Mean Cobb angle in Group 1 improved from 650 (range 120–950) to 18.50 (range 0–280) and in Group 2 from 77.60 (range 400–1050) to 34.80 (range 100–620) [p < 0.05]. Mean pelvic obliquity in Group 1 improved from 14.30 (range 00–420) to 2.50 (range 00–50) and in Group 2 from 24.70 (100–510) to 9.70 (range 20–180) [p< 0.05]. Mean surgical time in Group 1 was 224 minutes as compared to 260 minutes in Group 2 [P< 0.05]. 6 patients in Group 2 had proximal junctional kyphosis and implant failure requiring revision. One patient in each group had infection treated with antibiotic therapy.

Conclusions: PS fixation in CP patients, allowed significant correction of large curves without anterior release, eliminated proximal junctional kyphosis and instrumentation failure. Correction of pelvic obliquity was also superior due to three-dimensional corrective force of pedicle screws. Although PS fixation is expensive and technically demanding, it outweighs the costs incurred by two-stage surgery because of its superior durability correction.