Minimally Invasive Percutaneous Fixation Techniques for Metastatic Spinal Disease

Objective: Surgical treatment of spinal metastasis is generally a palliative procedure. Although minimally invasive surgical (MIS) techniques are supposedly less morbid than open techniques, there is a lack of stratification of MIS techniques based on anticipated longevity. A simple stratification into three percutaneous surgical techniques based on modified Tokuhashi score is here proposed. Methods: Patients recommended for spinal surgery for metastatic spinal disease between 2009 and 2012 and operated on by the senior author (RJM) were retrospectively reviewed. One of three MIS techniques was offered based on estimated survival using a modified Tokuhashi score. Technique #1 is suitable for patients with predicted short longevity (<6 months). Using a mini-open midline or paramedian decompression and percutaneous screw fixation, the goal here is for rapid mobilization and minimization of hospitalization. Technique #2 is suitable for patients with predicted medium longevity (6-12 months). They are suitable for decompression and/or cement vertebral body replacement and a two levels stabilization. Technique #3 is suitable for patients with predicted long term survival survival (>12 months). In these patients, the primary goal of surgery is a wide local or marginal resection of tumor, decompression of the neurological elements and a robust stabilization construct. They are suitable for an open 360 degrees decompression, vertebral body reconstruction and a multilevel stabilization. Results: The study included eight patients with a mean age of 59 years (range, 36-72 years). Mean modified Tokuhashi score was 10 (range, 7-13) with three patients in the short term, two in the medium term and three in the long term survival category. Mean blood loss was 700 mL (range, 100-1200 mL), mean operating time 280 min (range, 120-360 min) and length of stay in the hospital was on average 13 days (range, 3-30 days). Conclusion: The authors present three minimally invasive technique options for the management of spinal metastatic disease corresponding to three clinical prognostic categories. In this small series, MIS techniques resulted in speedy recovery, minimal morbidity and no mortality.