Indications for surgical treatment of thoracolumbar kyphosis in patients with Mucopolysaccharidosis

Introduction. Circumferential fusion of kyphosis in patients with MPS is currently accepted as the most effective surgical approach. However, long-term results remain debatable. This study assesses the effectiveness of posterior-only compared to circumferential fusion. Methods. Eleven patients (7 male, 4 female) with MPS and thoracolumbar kyphosis underwent surgical treatment. Hurler Syndrome (type I) was diagnosed in 5 patients, Morquio Syndrome (type IV) in 2, and Maroto-Lamy (type VI) in 4 patients. Indications for surgical treatment included more than 40° kyphosis, sagittal spinal imbalance, progressive neurological symptoms and severe pain. In 3 cases, patients underwent circumferential arthrodesis combining anterior and posterior approaches. In 8 cases, instrumentation included hooks and/or pedicular screws, placed two levels above and two levels below the deformity apex. The follow-up period ranged from 2 to 5 years. Results. In 8 cases solid spinal fusion was achieved. Complications after surgical treatment were observed in 4 patients (36%). PJK developed in one case 2 years after surgery, pseudarthrosis was observed in one case, wound suppuration was observed in one case, and a broken metal rod in one case. Conclusions. Surgical treatment of MPS patients with thoracolumbar kyphosis is accompanied by a high risk of complications when circumferential stabilization is performed. Most authors and our data show that the most optimal method of surgical treatment of thoracolumbar deformation is dorsal correction and fixation in combination with a wide laminectomy at the level of stenosis. The second stage includes the anterior decompression and interbody fusion. However, if the patient’s lung function is dramatically compromised, and a high risk of respiratory complications exists, surgery may be limited to only posterior correction and fixation in conjunction with a wide laminectomy, which allows to achieve a comparable level of fixation with a lower risk of complications