Brain reorganization in patients with spinal cord compression evaluated using fMRI.

OBJECTIVE: This prospective study characterizes the reorganization that occurs within the primary sensorimotor cortices following decompression of cervical spinal stenosis. METHODS: Twelve right-handed patients with cervical myelopathy underwent blood oxygenation level dependent functional MRI (fMRI) prior to decompression and 6 months following surgery. Ten right-handed controls also underwent fMRI. All subjects performed a finger-tapping paradigm with the right hand. Volume time course data were corrected for temporal serial correlation and % normalized before inclusion in the general linear model. Activation maps were created for each group using a threshold of p < 0.005 with Bonferroni correction. Between-group differences in left hemisphere volume of activation (VOA) were measured along the precentral gyrus (PrCG) and postcentral gyrus (PoCG). Each subject also completed clinical questionnaires. RESULTS: Prior to surgery, patients demonstrated a larger VOA (1.23 cm(3), t(max) = 11.8) in comparison to controls within the PrCG. This difference increased following surgery (2.99 cm(3), t(max) = 13.6). Within the PoCG, controls demonstrated a larger VOA (0.53 cm(3), t(max) = 8.28) than preoperative patients. This difference decreased by 0.12 cm(3) (t(max) = 7.05) following surgery. Preoperatively, patients had a 21.7 cm(3) VOA (t(max) = 29.4) within the sensorimotor cortex with the center of gravity located within Brodmann area (BA) 3. Following surgery, the VOA increased to 23.1 cm(3) (t(max) = 26.1) within BA 3. There were significant improvements in clinical outcomes following surgery. CONCLUSIONS: Spinal cord compression resulted in an increase in volume of activation (VOA) within the precentral gyrus (PrCG) and a loss of VOA within the postcentral gyrus (PoCG) in comparison to controls. Surgical decompression results in cortical reorganization with enlarging VOA within both the PrCG and PoCG.

Efficacy of closed wound suction drainage after single-level lumbar laminectomy.

The use of closed suction drainage after spinal surgery remains controversial. The purpose of this study was to determine the indications for closed suction drainage after single-level lumbar surgery. Two hundred patients who were scheduled to undergo single-level lumbar surgery without fusion were prospectively randomized into two groups. One group had a closed wound suction drain placed deep to the lumbodorsal fascia before routine closure, whereas the second group had no drain placed. Hemostasis was achieved in all patients before the surgeon had knowledge of the randomization outcome. All drains were removed on the 2nd postoperative day, and the amount of drainage was recorded. After surgery, the patients were evaluated for signs and symptoms of continued wound drainage, hematoma/seroma formation, and/or infection as well as evidence of an acquired neurologic deficit. One hundred three patients had a drain placed before closure and two patients developed postoperative wound infection, both of which were successfully treated with orally administered antibiotics. Of the 97 patients who had no drain placed after the surgical procedure, one patient developed a postoperative wound infection that was treated with surgical incision and drainage, as well as intravenously administered antibiotics. Statistical analysis revealed that the presence or absence of a drain did not affect the postoperative infection rate. No new neurologic deficits occurred in any postoperative patient. The use of drains in single-level lumbar laminectomy without fusion did not affect patient outcome. There was no significant difference in the rate of infection or wound healing and no patient developed a postoperative neurologic deficit.