The impact of obesity on the accuracy of DXA BMD for DXA-equivalent BMD estimation.

INTRODUCTION: As the radiomics technique using texture features in CT is adopted for accessing DXA-equivalent bone mineral density (BMD), this study aims to compare BMD by DXA and predicted BMD to investigate the impact of obesity and central obesity in general patients. MATERIALS AND METHODS: A total of 710 cases (621 patients) obtained from May 6, 2012, to June 30, 2021, were used in the study. We focused both their abdomen & pelvis CT's first lumbar vertebrae axial cuts to predict estimated BMD and bone mineral content (BMC). In each patient's CT, we extracted the largest trabecular region of the L1 vertebral body as a region of interest (ROI) using the gray-level co-occurrence matrices (GLCM) technique, and linear regression was applied to predict the indices. Cases were divided by central obesity/overall obesity and normal group by body mass index (BMI), waist circumference (WC), or index of central obesity (ICO) standard. RESULTS: The coefficients were all above 0.73, respectively. P-values from ICO were over 0.05 when the measures were Hip BMD and Hip BMC. In contrast, those from ICO were 0.0131 and 0.0351 when the measures were L1 BMD and L1 BMC, respectively, which show a difference between the two groups. CONCLUSIONS: The CT HU texture analysis method was an effective and economical method for measuring estimated BMD and BMC and evaluating the impact of obesity. We found that central obesity especially exerted an effect on the disturbance of the clinical BMD measurements since groups were significantly different under the ICO standard.

Axial Neck Pain after Cervical Laminoplasty with Preserving C7 Spinous Process Using C7 Arcocristectomy: A Prospective Study.

STUDY DESIGN: Single-blinded, randomized, single-center, prospective study. PURPOSE: This study aims to compare the radiographical and clinical outcomes between C7 laminoplasty and C7 arcocristectomy, which preserves the C7 spinous process. OVERVIEW OF LITERATURE: Laminoplasty is a widely used surgical method that decompresses the cervical spinal cord. However, axial neck pain is one of the major factors of dissatisfaction, and still, it is not clearly solved the reduction method of postoperative axial neck pain. METHODS: Thirty-one patients with multilevel cervical spondylotic myelopathy who required C6-C7 level decompression surgery were operated and followed up for 24 months. One group (15 patients) received C7 arcocristectomy without laminoplasty, and the other group (16 patients) received C7 laminoplasty. Flexion, neutral, and extension angles were measured using the Cobb method at C2-C7 to evaluate preoperative and postoperative radiographic parameters. Range of motion (ROM), ROM preservation rate of the cervical spine, C2-C7 sagittal vertical axis (SVA), and T1 slope were measured using C-spine lateral X-ray. The Visual Analog Scale (VAS) and modified Japanese Orthopedic Association (JOA) score were used to compare preoperative and postoperative clinical symptoms. RESULTS: Flexion, neutral, extension angles of the cervical spine, C2-C7 SVA, T1 slope, ROM, ROM preservation rate, and modified JOA score were not significantly different between the two groups (p>0.05). In the C7 arcocristectomy group, the average postoperative VAS for axial neck pain was increased in 13.3% (2/15) of the patients, whereas in the C7 laminoplasty group, the average postoperative VAS was increased in 43.8% (7/16) of the patients (p=0.018). CONCLUSIONS: C7 arcocristectomy, which preserves the C7 spinous process and posterior structures, is a useful technique for relieving axial neck pain.