Minimally Invasive Spinal Stabilization Using Fluoroscopic-Guided Percutaneous Screws as a Form of Palliative Surgery in Patients with Spinal Metastasis

STUDY DESIGN: Prospective cohort study. PURPOSE: To report the outcome of 50 patients with spinal metastases treated with minimally invasive stabilization (MISt) using fluoroscopic guided percutaneous pedicle screws with/without minimally invasive decompression. OVERVIEW OF LITERATURE: The advent of minimally invasive percutaneous pedicle screw stabilization system has revolutionized the treatment of spinal metastasis. METHODS: Between 2008 and 2013, 50 cases of spinal metastasis with pathological fracture(s) with/without neurology deficit were treated by MISt at our institution. The patients were assessed by Tomita score, pain score, operation time, blood loss, neurological recovery, time to ambulation and survival. RESULTS: The mean Tomita score was 6.3+/-2.4. Thirty seven patients (74.0%) required minimally invasive decompression in addition to MISt. The mean operating time was 2.3+/-0.5 hours for MISt alone and 3.4+/-1.2 hours for MISt with decompression. Mean blood loss for MISt alone and MISt with decompression was 0.4+/-0.2 L and 1.7+/-0.9 L, respectively. MISt provided a statistically significant reduction in visual analog scale pain score with mean preoperative score of 7.9+/-1.4 that was significantly decreased to 2.5+/-1.2 postoperatively (p=0.000). For patients with neurological deficit, 70% displayed improvement of one Frankel grade and 5% had an improvement of 2 Frankel grades. No patient was bed-ridden postoperatively, with the average time to ambulation of 3.4+/-1.8 days. The mean overall survival time was 11.3 months (range, 2-51 months). Those with a Tomita score or =8 with a mean survival of 14.1+/-12.5 months and 6.8+/-4.9 months, respectively (p=0.019). There were no surgical complications, except one case of implant failure. CONCLUSIONS: MISt is an acceptable treatment option for spinal metastatic patients, providing good relief of instability back pain with no major complications.

Fluoroscopy-Guided Lumbar Drainage of Cerebrospinal Fluid for Patients in Whom a Blind Beside Approach Is Difficult

OBJECTIVE: To evaluate the rates of technical success, clinical success, and complications of fluoroscopy-guided lumbar cerebrospinal fluid drainage. MATERIALS AND METHODS: This retrospective study was approved by the Institutional Review Board of our hospital, and informed consent was waived. Ninety-six procedures on 60 consecutive patients performed July 2008 to December 2013 were evaluated. The patients were referred for the fluoroscopy-guided procedure due to failed attempts at a bedside approach, a history of lumbar surgery, difficulty cooperating, or obesity. Fluoroscopy-guided lumbar drainage procedures were performed in the lateral decubitus position with a midline puncture of L3/4 in the interspinous space. The catheter tip was positioned at the T12/L1 level, and the catheter was visualized on contrast agent-aided fluoroscopy. A standard angiography system with a rotatable C-arm was used. The definitions of technical success, clinical success, and complications were defined prior to the study. RESULTS: The technical and clinical success rates were 99.0% (95/96) and 89.6% (86/96), respectively. The mean hospital stay for an external lumbar drain was 4.84 days. Nine cases of minor complications and eight major complications were observed, including seven cases of meningitis, and one retained catheter requiring surgical removal. CONCLUSION: Fluoroscopy-guided external lumbar drainage is a technically reliable procedure in difficult patients with failed attempts at a bedside procedure, history of lumbar surgery, difficulties in cooperation, or obesity.

Anatomic Study of Injection Point of Piriformis Muscle on Cadaver Study

OBJECTIVE: To identify the optimal site for piriformis muscle injection, using easily detectable sacroiliac joint as a landmark, under fluoroscopic guidance. METHOD: We examined the anatomic relationships of the sciatic nerve, piriformis muscle and sacroiliac joint in 18 buttocks from 9 cadavers. The distance from the inferior margin of the sacroiliac joint to the piriformis muscle at the crossing point with the sciatic nerve, and the width of the sciatic nerve at that point were measured. We assessed the depth of the piriformis muscle and the sciatic nerve using ultrasonography in asymptomatic controls. RESULTS: The mean distance from the inferior margin of the sacroiliac joint to the piriformis muscle at the crossing point with the sciatic nerve was 15.7+/-3.4 (12~22) mm laterally and 16.5+/-4.1 (10~25) mm caudally. The mean width of the sciatic nerve at that point was 15.4+/-3.7 (12~22) mm. Ultrasonographic findings revealed the mean distance as 4.48+/-0.49 cm from the skin to the surface of the piriformis muscle and as 5.68+/-0.62 from the skin to the surface of the sciatic nerve. CONCLUSION: The most optimal injection site for piriformis syndrome was located 15.6+/-3.4 (12~22) mm laterally and 16.5+/-4.1 (10~25) mm caudally from the inferior margin of the sacroiliac joint.