Degenerative Lumbar Spondylolisthesis with Spinal Stenosis: A Comparative Study of 5-Year Outcomes Following Decompression with Fusion and Microendoscopic Decompression

STUDY DESIGN: Retrospective review of prospectively collected outcome data. PURPOSE: To compare 5-year outcomes following decompression with fusion (FU) and microendoscopic decompression (MED) in patients with degenerative lumbar spondylolisthesis (DLS) and to define surgical indication limitations regarding the use of MED for this condition. OVERVIEW OF LITERATURE: There have been no comparative studies on mid- or long-term outcomes following FU and MED for patients with DLS. METHODS: Forty-one consecutive patients with DLS were surgically treated. Sixteen patients first underwent FU (FU group), and 25 then underwent MED (MED group). The 5-year clinical outcomes following the two surgical methods were compared using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire. RESULTS: The degree of improvement (DOI) for social life function was significantly greater in the MED group than in the FU group. Although not statistically significant, DOIs for the other four functional scores were also greater in the MED group than in the FU group. However, patients with a large percentage of slippage in the neutral position might experience limited improvement in low back pain, those with a large percentage of slippage at maximal extension might experience limited improvement in three functional scores, and those with a small intervertebral angle at maximal flexion might have limited improvement in three functional scores after MED for DLS. Therefore, we statistically compared the DOIs between the FU and MED groups regarding the preoperative percentage of slippage in the neutral position among patients with greater than 20% slippage, the preoperative percentage of slippage at maximal extension among patients with greater than 15% slippage, and the intervertebral angle at flexion among patients with angles lesser than −5°; however, there were no statistically significant differences between the two groups. CONCLUSIONS: MED is a useful minimally invasive surgical procedure that possibly offers better clinical outcomes than FU for DLS.

Surgical Outcome for Hemodialysis-Related Upper Cervical Lesions

STUDY DESIGN: A retrospective study. PURPOSE: To investigate the surgical outcome for hemodialysis-related upper cervical lesions. OVERVIEW OF LITERATURE: Surgical outcome of lower cervical lesions in patients undergoing hemodialysis has been reported. However, surgical outcome for upper cervical lesions in hemodialysis patients is unclear. METHODS: Upper cervical lesions in nine patients undergoing hemodialysis were surgically treated. Mean age at surgery was 61.6 years (range, 52-68 years), and the mean follow-up period was 45.4 months (range, 2-98 months). Patients had undergone hemodialysis for an average of 25.3 years (range, 16-40 years) at surgery. Seven patients with destructive spondyloarthropathy (DSA) of the upper cervical spine were treated with atlantoaxial or occipitocervical fixation. Two patients with retro-odontoid pseudotumors were treated with C1 posterior arch resection alone. Japanese Orthopedic Association (JOA) scores for cervical myelopathy, postoperative complications, postoperative radiography, and preoperative and postoperative occipital pain were evaluated. RESULTS: Mean preoperative and postoperative JOA score was 3.7 and 8.1, respectively. The seven patients with DSA had severe preoperative occipital pain that disappeared postoperatively. Postoperative radiography showed solid bone union in DSA cases and no instability in pseudotumor cases. CONCLUSIONS: Satisfactory surgical outcome was observed for hemodialysis-related upper cervical lesions.

Differential Diagnosis of Tumoral Lesions in the Spinal Canal in Patients Undergoing Hemodialysis

STUDY DESIGN: A retrospective study. PURPOSE: To clarify the features useful for the differential diagnosis of spinal canal tumoral lesions in patients undergoing hemodialysis. OVERVIEW OF LITERATURE: Tumoral lesions in the spinal canal are rarely found in hemodialysis patients. Therefore, the differential diagnosis of tumoral lesions in the spinal canal in hemodialysis patients has been very difficult. METHODS: Spinal canal tumors in 17 patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis were investigated. Histopathological analysis was conducted for all specimens obtained during surgery. The tumoral lesions were categorized into 3 groups on the basis of histopathology: spinal cord tumor, amyloidoma, and other. Patient medical history and diagnostic images of each group were reviewed. RESULTS: Eight of 17 cases were histopathologically diagnosed as spinal cord tumors and were neurinomas, 6 were amyloidomas, and 3 were classified as other. The rate of spinal cord tumors was 47.1% (8 of 17 cases), which revealed the most frequent lesion type. The rate of amyloidomas and other types was 35.3% (6 of 17 cases) and 17.6% (3 of 17cases), respectively. In the amyloidoma group, the mean duration of hemodialysis (24.3 years) was longer than that of spinal cord tumors and other types (9.2 years and 8.6 years, respectively). All spinal cord tumors were intradural extramedullary, whereas all amyloidomas and other types were extradural. CONCLUSIONS: The rate of each tumoral lesion, the duration of hemodialysis, and the tumoral localization are important features for the differential diagnosis of tumoral lesions in the spinal canal in hemodialysis patients.

Pycnodysostosis with Multi-Segmental Spinal Canal Stenosis due to Ossification of the Yellow Ligament

Pycnodysostosis is an autosomal recessive disorder characterized by osteosclerosis, small stature, acro-osteolysis of the distal phalanges, loss of the mandibular angle, separated cranial sutures with open fontanels, and frequent fractures. One identified cause of the disease is reduced activity of the cysteine protease cathepsin K. A 48-year-old woman with a history of frequent fractures presented with a severe gait disturbance. Radiography, computed tomography, magnetic resonance imaging, and gene analysis were performed. Physical examination revealed open fontanels, and radiographs showed increased bone density. DNA sequence analysis revealed a deletion mutation of the cathepsin K gene. We diagnosed pycnodysostosis based on these findings. The magnetic resonance and computed tomography images demonstrated multilevel spinal canal stenosis due to ossification of the yellow ligament. We performed a laminectomy, and the patient's neurological signs and symptoms improved. To our knowledge, this is the first case of pycnodysostosis with ossification of the yellow ligament.

Surgical Treatment for Atlanto-Occipital Subluxation due to Destructive Spondyloarthropathy in a Patient Undergoing Long-Term Hemodialysis

Destructive spondyloarthropathy (DSA) has been reported in patients undergoing long-term hemodialysis. Cervical spinal lesions, including those of the upper cervical spine, are reported to be some of the most common. To our knowledge, we report for the first time, a case of atlanto-occipital subluxation requiring surgical treatment due to severe myelopathy and nuchal pain in a patient undergoing long-term hemodialysis. The patient was a 66-year-old woman who had undergone hemodialysis for 40 years. She visited our hospital due to an acute progression of gait disturbance and severe nuchal pain. Computed tomography showed posterior subluxation of the atlanto-occipital joints. DSA was also observed in the lower cervical spine. Magnetic resonance imaging showed spinal canal stenosis at both the upper and lower cervical levels. We performed Oc-C7 fixation, C1 laminectomy, and C3-C7 laminoplasty. We first recognized that the atlanto-occipital subluxation was caused by the extremely long-term, in this case, 40 years, hemodialysis.

Incidence of Nocturnal Leg Cramps in Patients with Lumbar Spinal Stenosis before and after Conservative and Surgical Treatment

PURPOSE: To examine the effects of conservative and surgical treatments for nocturnal leg cramps in patients with lumbar spinal stenosis (LSS). Nocturnal leg cramps is frequently observed in patients with peripheral neuropathy. However, there have been few reports on the relationship between nocturnal leg cramps and LSS, and it remains unknown whether conservative or surgical intervention has an impact on leg cramps in patients with LSS. MATERIALS AND METHODS: The subjects were 130 LSS patients with low back and leg pain. Conservative treatment such as exercise, medication, and epidural block was used in 66 patients and surgical treatment such as decompression or decompression and fusion was performed in 64 patients. Pain scores and frequency of nocturnal leg cramps were evaluated based on self-reported questionnaires completed before and 3 months after treatment. RESULTS: The severity of low back and leg pain was higher and the incidence of nocturnal leg cramps was significantly higher before treatment in the surgically treated group compared with the conservatively treated group. Pain scores improved in both groups after the intervention. The incidence of nocturnal leg cramps was significantly improved by surgical treatment (p=0.027), but not by conservative treatment (p=0.122). CONCLUSION: The findings of this prospective study indicate that the prevalence of nocturnal leg cramps is associated with LSS and severity of symptoms. Pain symptoms were improved by conservative or surgical treatment, but only surgery improved nocturnal leg cramps in patients with LSS. Thus, these results indicate that the prevalence of nocturnal leg cramps is associated with spinal nerve compression by LSS.

Conservative and Surgical Treatment Improves Pain and Ankle-Brachial Index in Patients with Lumbar Spinal Stenosis

PURPOSE: The pathological mechanism of lumbar spinal stenosis is reduced blood flow in nerve roots and degeneration of nerve roots. Exercise and prostaglandin E1 is used for patients with peripheral arterial disease to increase capillary flow around the main artery and improve symptoms; however, the ankle-brachial index (ABI), an estimation of blood flow in the main artery in the leg, does not change after treatment. Lumbar spinal nerve roots contain somatosensory, somatomotor, and unmyelinated autonomic nerves. Improved blood flow by medication with prostaglandin E1 and decompression surgery in these spinal nerve roots may improve the function of nerve fibers innervating muscle, capillary, and main vessels in the lower leg, resulting in an increased ABI. The purpose of the study was to examine whether these treatments can improve ABI. MATERIALS AND METHODS: One hundred and seven patients who received conservative treatment such as exercise and medication (n=56) or surgical treatment (n=51) were included. Low back pain and leg pain scores, walking distance, and ABI were measured before treatment and after 3 months of conservative treatment alone or surgical treatment followed by conservative treatment. RESULTS: Low back pain, leg pain, and walking distance significantly improved after both treatments (p<0.05). ABI significantly increased in each group (p<0.05). CONCLUSION: This is the first investigation of changes in ABI after treatment in patients with lumbar spinal stenosis. Improvement of the spinal nerve roots by medication and decompression surgery may improve the supply of blood flow to the lower leg in patients with lumbar spinal stenosis.