Methods: We evaluated 48 patients (38 boys and 10 girls) with bilateral L5 spondylolysis diagnosed during or before high school. L5 spondylolysis was classified into two groups: fresh group (bilateral fresh spondylolysis cases), and terminal group (cases wherein one side had fresh spondylolysis and the contralateral side had terminal spondylolysis). We investigated the age of examination and bone healing rate in both groups. We investigated progressive-stage lesions and bone healing rate with or without progressive-stage lesions. Results: The bone healing rate in the fresh group was significantly higher than that in the terminal group 72.0% vs. 26.1%, p =0.003). In both the groups, the bone healing rate was significantly higher in patients without progressive-stage lesions than in those with progressive-stage lesions. Conclusions Bone healing of progressive-stage fresh spondylolysis was not achieved by conservative treatment when contralateral terminal spondylolysis was present in adolescents with bilateral L5 spondylolysis. Our results suggest that bilateral L5 spondylolysis treatment strategies must be determined based on the combination of the stages present.

Objective: Whether or not emergent decompression/fusion surgery for paralysis caused by metastatic spinal tumors of unknown origin improves patient neurological outcome and survival remains unclear. This study aimed to evaluate the clinical outcomes of emergent decompression/fusion surgery for paralysis caused by spinal tumors of unknown or not previously diagnosed origin.Patients and Methods: Data from the medical records of 11 patients with spinal tumors of unknown origin (study group) were compared with those of 15 patients with metastatic spinal tumors of known origin (control group). The outcome measures were postoperative performance status, motor function evaluated with the Frankel grade, and actual survival after surgery as compared with the estimated survival calculated using the Tokuhashi score. χ2 analyses were performed to evaluate differences between the groups.Results: The mean performance status was 3.6 preoperatively, which improved to 2.9 postoperatively (P<0.05), in the unknown origin group and 3.6 preoperatively, which improved to 2.7 postoperatively (P<0.05), in the control group. Seven patients (64%) in the unknown origin group showed improvement in paralysis by ≥1 Frankel grade. By contrast, only 4 patients (27%) in the control group showed improvement in paralysis. The unknown origin group tended to show better improvement (P=0.05). All the patients in the unknown origin group underwent adjuvant therapy after definitive diagnosis following surgery. The unknown origin group showed a slight tendency toward better survival than toward the estimated survival.Conclusion: Emergent decompression/fusion surgery for patients with paralysis caused by metastatic tumors of unknown origin is potentially useful for diagnosing tumor origin and improving neurological outcomes and performance status, and thus for extending survival.

Objective: The aim of this study was to determine the prevalence of curable and pseudoarthrosis stages of adolescent lumbar spondylolysis under high school students complaining of and seeking medical consultation for low back pain.Patients and Methods: We analyzed age, sex, morbidity, presence of spina bifida occulta (SBO), and competitive sport discipline of patients with lumbar spondylolysis. We then stratified their pathological stage using a modified classification system via magnetic resonance imaging and computed tomography.Results: Of 507 patients, 451 lesions in 268 patients were diagnosed with lumbar spondylolysis (average age, 14.7 years; sex ratio, 215:53 male/female). Morbidity levels were as follows: L1, 1 lesion in 1 patient; L2, 9 lesions in 5 patients; L3, 38 lesions in 25 patients; L4, 106 lesions in 74 patients; L5, 297 lesions in 189 patients, and SBO verified in 111 patients. A total of 264 patients played a specific sport: baseball, 93; soccer, 49; volleyball, 21; track and field, 21; basketball, 20; others, 164. The prevalence of curable- and pseudoarthrosis-stage lumbar spondylolysis was 206 lesions in 142 patients, and 141 lesions in 87 patients, respectively.Conclusion: With 59.3% of patients having curable-stage lumbar spondylolysis, adolescent athletes with low back pain are urged to seek consultation. Furthermore, clinicians should perform magnetic resonance imaging to avoid misdiagnosis.

Objective: Spontaneous spinal epidural hematoma is rare and therefore difficult to diagnose. This study evaluated the clinical features of this condition in patients admitted to our hospital.Patients and Methods: We evaluated 12 patients with spontaneous spinal epidural hematoma who were treated at our hospital. We investigated the following variables in these patients: underlying diseases, medications used, initial symptoms, spinal level affected, whether transported to the hospital by ambulance, department where first evaluated, mass lesion on computed tomography with soft tissue window settings, time interval between symptom onset and diagnosis, treatment received, and Frankel classification on arrival and when last observed.Results: Five patients reported the use of antiplatelet or anticoagulant drugs. All patients in this study reported acute onset of severe pain as the initial symptom, and 10 patients reported some degree of paralysis accompanying the pain. With respect to the morbidity level, the cervical region was the most common site of involvement (n=7). Ten patients were transported to the hospital at night via ambulance. Five patients first visited the Department of Internal Medicine. Seven patients presented with a mass lesion on computed tomography with soft tissue window settings. The time interval between symptom onset and diagnosis ranged from 2 hours to 6 days. Three and 9 patients received conservative and surgical treatments, respectively. No patient showed worsening of Frankel classification.Conclusion: Acute onset of severe pain was the most characteristic clinical symptom. Spontaneous spinal epidural hematoma should be included in the differential diagnosis. Computed tomography with soft tissue window settings may rule out cerebrovascular disease and cardiovascular disease, and specifically detect a hematoma. Subsequent magnetic resonance imaging can diagnose a spontaneous spinal epidural hematoma at an early stage.

Purpose: This study aimed to examine the characteristics of lumbar spondylolysis with acute lumbar spondylolysis on one side and pseudoarthrotic spondylolysis on the other, relative to acute lumbar spondylolysis on one side only.Patients and Methods: Short-tau inversion recovery images obtained through magnetic resonance imaging were used to diagnose 58 patients with acute lumbar spondylolysis with bone marrow edema on one side only. A total of 20 patients who had pars defects on the contralateral side (terminal-stage pseudoarthrotic spondylolysis) were included in the contralateral pseudoarthrosis group (P group). The remaining 38 patients with normal images for the contralateral pars interarticularis were included in the unilateral lesion group, in which the contralateral side was normal (U group). We investigated the union rate, age, sex, lesion laterality, vertebral level, pathological stage, and existing spina bifida occulta in both groups.Results: The P group was characterized by a higher proportion of right-side cases, L5 lesions, more progressed pathological stage, and spina bifida occulta and a significantly lower union rate than the U group.Conclusion: The union rate in patients with lumbar spondylolysis with acute lumbar spondylolysis on one side and pseudoarthrotic spondylolysis on the opposite side was only 15%. We should inform patients with acute unilateral spondylolysis lesions and contralateral pseudoarthrosis about this poor union rate and urge them to choose their therapy accordingly.