Suspicious Reperfusion Injury of Spinal Cord After Multilevel Cervical Posterior Decompression without Remarkable Surgical Insult: Two Case Reports

STUDY DESIGN: Two case reports. OBJECTIVES: We present two cases of quadriplegia after posterior decompression with fusion caused by a suspicious reperfusion injury of spinal cord without remarkable surgical insult. SUMMARY OF LITERATURE REVIEW: Posterior decompression and posterolateral fusion have been reported as effective procedures in patients with multilevel myelopathy. However, postoperative spinal cord injury without remarkable intraoperative technical damage has been reported in a few articles. Reperfusion mechanism was suggested as one of the leading causes and reported in some animal models. MATERIALS AND METHODS: There was one case of ossification of the posterior longitudinal ligament and one developmental multilevel stenosis that underwent laminectomy with lateral mass instrumentation. After surgery, the patients presented with quadriplegia; MRI demonstrated swelling of the spinal cord and intramedullary lesion in two cases. RESULTS: After surgery, the patients presented with quadriplegia; MRI demonstrated swelling of the spinal cord and intramedullary lesion in two cases. CONCLUSION: Although patients with such a medical condition are rare, it is difficult to predict postoperative swelling of the spinal cord before surgery. The surgeon should thus be aware of such rare disease conditions involving the spinal cord before the surgical procedure.

Relation Between Adjacent Superior Segmental Disease and Facet Joint Violations After Posterolateral Lumbar Fusion

STUDY DESIGN: To analyze the relationship between the adjacent superior segment disease and facet joint violations after lumbar fusion. OBJECTIVES: We retrospectively analyzed the relationship between the adjacent superior segment disease and facet joint violations after lumbar fusion. SUMMARY OF LITERATURE REVIEW: Among numerous literatures regarding adjacent superior segment disease, there is no analysis concerning the relationship between adjacent superior segment disease and facet joint violations after lumbar fusion. MATERIALS AND METHODS: We reviewed 2056 patients who underwent lumbar fusion, between March 2004 and April 2009. Analysis was performed for 79 (3.8%) of the 2056 patients with adjacent superior segment disease and needed a second operation. A facet joint was considered as 3 types of violations with computed tomography scans if any of the following situations were encountered: pedicle screw clearly within the facet joint; pedicle screw head clearly within the facet joint; and pedicle screw and/or screw head within 1mm from or abutting the facet joint, without clear joint involvement. RESULTS: The incidence of the violations was 45% (36/79) of all patients and 28% (44/158) of all screws. The incidence of L4-5 facet joint violations was 35% (28/79) of patients with adjacent superior segment disease, statistically. CONCLUSIONS: Facet joint violations were observed in patients with the adjacent superior segment disease after posterolateral lumbar fusion. Because L3-4 facet joint violations increased when L4-5 fusion was done, more care should be taken to avoid facet joint violations when the surgeon is considered for insertion of the pedicle screws at L4-5.