Effectiveness and safety of preoperative distraction using modified halo-pelvic Ilizarov distraction assembly in patients with severe kyphoscoliosis.

Study design: A 2-year follow-up study.

Purpose: To evaluate the effectiveness of modified halo-pelvic Ilizarov distraction assembly in the management of patients with severe kyphoscoliosis.

Overview of literature: Severe and rigid scoliosis curves are always a challenge for operating surgeons. Preoperative correction through halo-pelvic devices successfully minimizes the severity of the curve; however, cumbersome complications are also reported with its use. Modified assembly could be safe for these cases.

Methods: Patients with severe kyphoscoliosis having coronal Cobb angle >90° were applied with modified halo-pelvic Ilizarov distraction assembly preoperatively. The modified assembly consisted of a pelvic component and halo ring, and distraction was given at the rate of 2-3 mm/day for 6-12 weeks. Complete clinical assessments along with pulmonary function tests were performed, and scoliosis series X-ray images were assessed for coronal and sagittal Cobb angle and other spinopelvic parameters before applying the assembly and during 2 years of follow-up.

Results: Thirty-four patients (age, 9-27 years; male/female ratio of 18:16) were included. The coronal and sagittal Cobb angles were 116°±16.2° and 84°±28.3°, respectively. Correction rates obtained through modified halo-pelvic assembly were nearly 52% (p=0.001) in coronal and 40% (p=0.001) in sagittal Cobb angles, with improvement in height (p=0.001). Apical vertebral translation and coronal balance were also improved significantly (p=0.001). Further improvements in all the parameters were obtained after definitive surgery, with improvements in the forced expiratory volume in 1 second (p =0.002) and forced vital capacity (p=0.001).

Conclusions: Our modified halo-pelvic Ilizarov distraction assembly can achieve good correction in severe spinal deformities without significant risk to neurology, has fewer complications, and promotes good patient compliance.