As scoliosis in arthrogryposis multiplex congenita (AMC) is unusual and the number of cases reviewed in previous studies is also relatively small, no previous study exists that has directly compared the results of spinal deformity correction between AMC and adolescent idiopathic scoliosis (AIS) patients. The aim of this study was to compare the radiographic and clinical outcomes of surgical correction of spinal deformity associated with AMC versus AIS.
Twenty-four adolescents with AMC were matched with 48 AIS patients in terms of Cobb angle of main curve, curve pattern, sex, age at surgery, Risser grade, and length of follow-up. Patients in both groups underwent posterior-only spinal correction and fusion procedures. The surgical outcomes and complications were analyzed and compared between the 2 groups.
In comparison to the AIS group, the AMC group had a significantly longer mean operation time (5.6 vs 4.4 hours, p = 0.002), more blood loss (1620 ± 250 ml vs 840 ± 260 ml, p < 0.001), and more fusion levels (14.1 ± 2.3 levels vs 12.4 ± 2.5 levels, p = 0.007) as well as a lower correction rate (44.3% ± 11.1% vs 70.8% ± 12.4%, p < 0.001) and a higher rate of loss of correction (5.0% ± 3.1% vs 2.1% ± 1.9%, p < 0.001). Nine patients in the AMC group had preoperative pelvic obliquity, which was corrected from a mean of 14.2° ± 8.4° to a mean of 4.3° ± 3.2° (p < 0.001) after the surgery. The thoracic lordosis and sagittal vertical axis were significantly improved in the AMC group. Notably, however, the AMC group was found to have higher rates of screw malpositioning (15.9% vs 9.5%, p = 0.002) and complications (8/24 [33.3%] vs 4/48 [8.3%], p = 0.016) as compared to the AIS group.
Correction of AMC-associated scoliosis tends to require a longer operating time and involve more fusion levels but results in less correction, more blood loss, and more complications, in comparison with AIS. In addition, more attention should be paid to pelvic obliquity and sagittal hyperlordosis in AMC patients.