Ryan Campbell1, Kevin Phan2, Ralph Mobbs3. 1. NeuroSpine Surgery Research Group (NSURG), Prince of Wales Private Hospital, Sydney, Australia; Faculty of Medicine, University of New South Wales (UNSW), Sydney, Australia. 2. NeuroSpine Surgery Research Group (NSURG), Prince of Wales Private Hospital, Sydney, Australia; Faculty of Medicine, University of New South Wales (UNSW), Sydney, Australia; Faculty of Medicine, University of Sydney, Sydney, Australia. 3. NeuroSpine Surgery Research Group (NSURG), Prince of Wales Private Hospital, Sydney, Australia; Faculty of Medicine, University of New South Wales (UNSW), Sydney, Australia; Prince of Wales Hospital Private, Sydney, Australia. Electronic address: ralphmobbs@hotmail.com.
Abstract
OBJECTIVE: To assess the validity of the proposed NeuroSpine Surgery Research Group Classification System through a retrospective analysis of patients treated surgically for lumbar facet joint cysts at a single institution. METHODS: In a cohort of 166 patients, sagittal T2-weighted magnetic resonance images were used to measure degree of spondylolisthesis, whereas axial T2-weighted magnetic resonance images were used to determine the percentage of vertebral canal occupied by the cyst. Grading was performed by 2 observers. Statistical analysis was conducted to correlate the given grades of each cyst with the treatment performed and the long-term outcomes of cyst and pain recurrence. RESULTS: In total, 158 were treated by decompression, whereas 8 underwent decompression with fusion; 25% of patients presented with a grade 1 cyst, 45% with a grade 2, 13% with a grade 3, 13% with a grade 4, and 4% with a grade 5 cyst. Of patients treated by decompression alone, a greater rate of recurrence was seen in grades 4 and 5 (29.4% and 33.3%) when compared with grades 1-3 (8.8%, 8.5%, and 0%, respectively, P < 0.05). There were no cases of a cyst recurrence after a fusion. CONCLUSIONS: The proposed NeuroSpine Surgery Research Group Classification System for lumbar facet joint cysts is effective in identifying patients most likely to endure a recurrent cyst after decompressive surgery. Patients with grades 4 and 5 cysts should be considered for decompressive surgery with concomitant stabilization of the involved segments on initial presentation. Crown
OBJECTIVE: To assess the validity of the proposed NeuroSpine Surgery Research Group Classification System through a retrospective analysis of patients treated surgically for lumbar facet joint cysts at a single institution. METHODS: In a cohort of 166 patients, sagittal T2-weighted magnetic resonance images were used to measure degree of spondylolisthesis, whereas axial T2-weighted magnetic resonance images were used to determine the percentage of vertebral canal occupied by the cyst. Grading was performed by 2 observers. Statistical analysis was conducted to correlate the given grades of each cyst with the treatment performed and the long-term outcomes of cyst and pain recurrence. RESULTS: In total, 158 were treated by decompression, whereas 8 underwent decompression with fusion; 25% of patients presented with a grade 1 cyst, 45% with a grade 2, 13% with a grade 3, 13% with a grade 4, and 4% with a grade 5 cyst. Of patients treated by decompression alone, a greater rate of recurrence was seen in grades 4 and 5 (29.4% and 33.3%) when compared with grades 1-3 (8.8%, 8.5%, and 0%, respectively, P < 0.05). There were no cases of a cyst recurrence after a fusion. CONCLUSIONS: The proposed NeuroSpine Surgery Research Group Classification System for lumbar facet joint cysts is effective in identifying patients most likely to endure a recurrent cyst after decompressive surgery. Patients with grades 4 and 5 cysts should be considered for decompressive surgery with concomitant stabilization of the involved segments on initial presentation. Crown