Objective: To evaluate the security and effectiveness of nano-hydroxyapatite/polyamide 66 (n-HA/PA66) cage in reconstruction of spinal stability after resection of spinal tumor.
Methods: Between January 2008 and December 2009, 11 patients with spinal tumor underwent surgical resection and strut graft with n-HA/PA66 cage. There were 6 males and 5 females with an average age of 44.5 years (range, 16-61 years). The average disease duration was 6.8 months (range, 2-14 months). The locations of lesions included cervical spine (2 cases), thoracic spine (6 cases), and lumbar spine (3 cases). Among them, there were 5 metastatic carcinomas, 2 giant cell tumors, 1 osteoblastoma osteosarcoma, 1 chondrosarcoma, and 2 non-Hodgkin lymphoma. According to Frankel criteria for nerve function classification, there were 1 case of grade A, 3 cases of grade B, 2 cases of grade C, 2 cases of grade D, and 3 cases of grade E.
Results: Incisions healed by first intention in all patients, no operative or postoperative complication occurred. Four cases of metastatic carcinoma died of primary disease during 5-9 months after operation. Seven cases were followed up 14.4 months on average (range, 10-18 months). All patients gained significant improvement of the neurological function at 3 months after operation. All cases obtained bone fusion and good spinal stability without displacement and subsidence of the n-HA/PA66 cage. The intervertebral height of the adjacent segments was (110.5 +/- 16.1) mm at 3 months after operation and (109.4 +/- 16.2 ) mm at the final follow-up, showing significant differences when compared with the preoperative height [(97.5 +/- 15.4) mm, P < 0.05], but no significant difference between 3 months after operation and the final follow-up. In 2 patients undergoing surgery via anterior approach, bilateral pleural effusion on both sides occurred and were cured after closed thoracic drainage. During the follow-up, 2 cases (1 chondrosarcoma and 1 giant cell tumor) relapsed and underwent reoperations.
Conclusion: n-HA/PA66 cage can provide satisfactory bone fusion and ideal spinal stability without increasing the risk of recurrence and complications during the surgical treatment of spinal tumors. It is an ideal selection for reconstruction of spinal stability.