Clinical Results from Subsidence and Loss of Lordosis after Anterior Cervical Discectomy and Fusion

OBJECT: The aim of this study is to analyze the statistical significance between the clinical result and subsidence and lordosis loss after anterior cervical discectomy and interbody fusion operation for degenerative cervical disc diseases. METHODS: From January 2004 to December 2006, retrospective study of 82 patients with symptomatic degenerative cervical disc disease who underwent anterior cervical discectomy and interbody fusion using the PEEK SolisTM cage and the carbon composite Osta-PekTM cage with autologous bone graft was done. Mean follow-up period was 13.2 months. Clinical results were assessed by bone fusion, subsidence, segmental lordosis loss and Odom's criteria. RESULTS: Of the 82 patients, single level fusion was accomplished in 67 patients and two-level fusion in 15 patients. Total accomplished fusion level was 97: C3/4 in 9 levels, C4/5 in 29 levels, C5/6 in 37 levels, C6/7 in 21 levels, C7/T1 in 1 level. 9 patients fit into complete resolved, 59 improved and 14 not changed, thus the success rate in clinical outcome was 82.9%. Bone fusion was successfully confirmed in the total of 82 patients. The height of disc space was decreased to 2.13+/-2.16mm: 2.64+/-1.81mm in the Osta-PekTM cage, 2.44+/-1.36mm in the PEEK SolisTM cage. The Osta-PekTM cage provided higher subsidence tendency than the PEEK SolisTM cage in our study. However, there was no statistical significance between the two cage groups. The subsidence and lordosis loss showed poor clinical outcome, but there was no statistical significance. CONCLUSIONS: There were no significant differences between the Osta-PekTM cage and PEEK SolisTM cage on clinical outco mes. Both cages showed low subsidences and lordosis loss with good fusion rate and clinical outcome.

Is a Revised Tokuhashi Scoring System Useful in Preoperative Evaluation of Metastatic Spinal Tumor Prognosis?

OBJECTIVE: The aim of this study was to evaluate the consistency between revised prognostic score derived from the Tokuhashi scoring system(TSS) and the actual patient survival period after surgical treatment at our institution. METHODS: From 1998 to 2005, surgically treated 44 patients with metastatic spine tumors were reviewed retrospectively at our institution. Among these 44 patients, 32 had died, 2 were alive at the time of the last follow-up evaluation, and 10 were lost to the follow-up. Only 32 patients who died after surgery have been investigated in this study. Preoperatively, patients were staged serveral standard diagnostic modalities, such as, plain radiographs, computed tomography, magnetic resonance imaging and etc. Each patient was evaluated using the TSS and placed in one of three groups depending upon this evaluation. RESULTS: The actual mean(+/-SD) survival period was 6.6 months(+/-1.14) for the first group (predicted survival periods in revised TSS, less than 6 months), 15.1 months(+/- 5.38) for the second group(predicted survival periods in revised TSS, 6 months or more) and 37.5 months(+/-8.70) for the third group(predictied survival period in revised TSS, 1 year or more). The survival periods for these groups were significantly different(p=0.0006). Applying the TSS for evaluation of prognosis of metastatic spinal tumors was found to be very reliable results with a statistically significance. Of six parameters measured in the TSS, Extraspinal bone metastases, metastases to the major internal organs, the primary tumor site contributed to predicting the survival periods. CONCLUSIONS: This study has revealed that the revised prognostic score resulting from the TSS predicts actual survival periods remarkably well. Hence, we thought that the revised TSS could be useful and reliable tool in prognosis of metastic spinal tumors.