OBJECTIVETo design a new surgical correction and fixation technique for the treatment of severe angular kyphosis, observe the feasibility, safety and effectiveness of the technique.

METHODSFrom May 2004 to February 2007, 16 cases with severe kyphosis (average 90.8 degrees, range 50 degrees-130 degrees) were treated with segmental resection osteotomy, section distraction, dual axial rotation correction and instrumentation fusion technique. The patients were inspected by local and total spine anteroposterior and lateral radiography pre-and postoperatively. The kyphotic Cobb angle was measured and 7 cases combined scoliosis Cobb angle was also measured. The Frankel Grading for neurological function, Oswestry Disability Index (ODI) and Patients Satisfactory Index (PSI) were evaluated preoperatively, postoperatively and at follow-up. The back pain relief was also observed.

RESULTSThe average surgical duration was 6.9 hours. The average blood loss was 4000 ml. The complications include 1 shifting of artificial vertebrae, 3 nerve root injury, 3 dural tear and 1 transitory dysfunction of lower extremity. All of these complications were relieved greatly after feasible treatment. The average follow-up time was 25 months. The average kyphotic angle was 90.8 degrees preoperatively, which was improved to 26.9 degrees immediately after surgery, and got an average correction rate of 72.5%. At follow-up, the average kyphotic angle was 28.9 degrees, and correction rate was 70.1%. The 7 cases who combined with scoliosis had an average Cobb angle of 35.9 degrees preoperatively, which decreased to 4.4 degrees immediately after surgery, and the correction rate was 87.2%. The correction rate was kept until follow-up (78.6%). Some patients got an improved neurological function. The Frankel Grading were E in 5 cases, D in 5 cases, C in 5 cases, and B in 1 case preoperatively. There were 10 cases of E grade, 3 cases of D grade, and 3 cases of C grade at follow-up. Except 3 cases who had no symptoms before surgery, the average ODI was 18.9 preoperatively, and 10.8 postoperatively. The average improvement of ODI was 52.7%. The PSI result showed a satisfied rate of 93.8%. The back pain of 3 cases were totally relieved after surgery.

CONCLUSIONSSegmental resection osteotomy with dual axial rotation correction and fusion technique is an effective way to treat severe angular kyphosis. It is a safe technique and has high correction rate. The long-term results is acceptable.