rform surgery in the setting of cervical OPLL remains unknown. It is important to know the influence of symptom duration on postoperative outcomes to facilitate discussions regarding the timing of surgery. Patients and Methods: The study included 395 patients (291 men and 104 women; mean age, 63.7 ± 11.4 yr): 204 were treated with laminoplasty, 90 with posterior decompression and fusion, 85 with anterior decompression and fusion, and 16 with other procedures. The Japanese Orthopedic Association (JOA) score and patient-reported outcomes of the JOA Cervical Myelopathy Evaluation Questionnaire were used to assess clinical outcomes preoperatively and 2 years after surgery. Logistic regression analysis was used to identify factors associated with the achievement of minimum clinically important difference (MCID) after surgery. Results: The recovery rate was significantly lower in the group with symptom duration of ≥5 years compared with the groups with durations of <0.5 years, 0.5 to 1 year,

the most common form of spinal cord dysfunction in adults; however, imaging surveillance for myelopathy remains poorly characterized. Patients and Methods. Symptomatic DCM patients were examined in maximum neck flexion-extension and neutral positions in a 3T-magnetic resonance imaging scanner and allocated to 2 groups: (1) Patients with visible intramedullary hyperintensity (IHIS) on T2-weighted imaging (IHIS+, n = 10); and (2) Patients without IHIS (IHIS−, n = 11). Range of motion, space available for the spinal cord, apparent diffusion coefficient (ADC), axial diffusivity (AD), radial diffusivity, and fractional anisotropy were measured and compared between the neck positions and between the groups as well as between control (C2/3) and pathologic segments. Results. Significant differences between the control level (C2/3) and pathologic segments were appreciated for the IHIS+ group at neutral neck position in AD; at flexion in ADC and AD; and at neck extension in ADC, AD, and fraction

cal approaches used to treat lumbar degenerative disk disease. However, there is a paucity of studies comparing the risk of ASD after these procedures. Methods. Patients who underwent 1- to 2-level LDA or ALIF between 2010 and 2022 were identified in the PearlDiver Mariner insurance all-claims database. Exclusion criteria included the history of prior lumbar spine surgery or surgery for tumors, trauma, or infection. 1:1 propensity matching was performed using demographic factors, medical comorbidities, and surgical factors, which were significantly associated with ASD. Results. 1:1 propensity matching created two equal groups of 1625 patients without baseline differences who underwent LDA or ALIF. LDA was significantly associated with a lower risk of ASD (relative risk: 0.932, 95% CI, 0.899–0.967, P<0.001) and need for revision within 30 days (relative risk: 0.235, 95% CI, 0.079–0.698, P=0.007). There were no differences in all-cause surgical and medical complications between both grou