A Primary Study Of Posterior Osteotomy In The Treatment Of Ankylosing Spondylitis With Thoracolumbar Stress Fracture

Objectives: To analyze the pathological feature of spinal stress fractures in ankylosing spondylitis, and to investigate the efficacy of posterior osteotomy in the treatment of ankylosing spondylitis with thoracolumbar fracture.Materials and Methods: The clinical data of 16 patients with ankylosing spondylitis combined with thoracolumbar fracture in the department of orthopedics of the first clinical medical college of Fujian Medical University from 2009.09.01 to 2014.09.01 were retrospectively analyzed. All patients underwent surgery using posterior osteotomy for correction of kyphosis. The data of preoperative and postoperative Cobb angle, the Frankel’s classification, and JOA score were collected and analyzed. The preoperative and postoperative lateral appearance, the improvement of life and work and the occurrence of complication were documented to evaluate the effect of posterior osteotomy.Results: The average preoperative Cobb angle was 21.61°±22.65°,and the average Cobb angle at final follow-up was-8.54°±20.49°. The postoperative Cobb angles were significantly improved in all patients, with an average of 30.37°±23.65°. The average preoperative JOA score was 14.13±3.64, which improved to 24.13±1.55 at final follow-up, with an improvement rate of 69.70±7.43%. For the Frankel’s classification, 10 cases in class D improved to class E after surgery. All patients had bony union. No broken nails, broken rods, loose, screw migration into the intervertebral foramen or spinal canal were found in postoperative and follow-up X-ray. Their appearance and living and working conditions were improved in all patients. No complication was found after surgery.Conclusion:The pathological characteristics of ankylosing spondylitis combinedwith thoracolumbar fracture including: osteoporosis combined with kyphosis deformity, insidious onset, high rate of nerve damage, and the formation of pesudoarthrosis. Posterior Osteotomy can effectively restore the stress axis of the spine, keep sagittal balance, restore canal volume, release spinal compression, and improve the function of the spinal cord. Long- segmental fixation after posterior osteotomy and a good closing of vertebral body at the osteotomy level will help the final bony union. The posterior osteotomy and fixation is an effective and reliable surgical method to treat the ankylosing spondylitis with thoracolumbar fracture.