Limb muscle strength asymmetry affects many physical abilities. The present study (1) quantified limb muscle asymmetry in patients with adolescent idiopathic scoliosis (AIS); (2) compared AIS patients with major thoracolumbar/lumbar (TL/L) or major thoracic (MT) curves; (3) examined correlations between limb muscle asymmetry and radiographic parameters. Patients with AIS with major TL/L curves (Lenke type 5C) and MT curves (Lenke Type 1A) who underwent posterior spinal fusion at our university hospitals were included. Patients with left hand dominance were excluded. Body composition was measured using whole-body dual-energy X-ray absorptiometry and asymmetry of left and right side skeletal muscles were evaluated. Upper extremity skeletal muscles on the dominant side were significantly larger than those on the nondominant side in both Lenke1A and 5C groups. The asymmetry of upper extremity skeletal muscles was significantly greater in the Lenke1A group than in the Lenke5C group. Additionally, the size of the asymmetry did not correlate with the magnitude of the major curve and rotational deformation but did correlate with a right shoulder imbalance in the Lenke1A group. These results suggest that in AIS with a constructive thoracic curve, right shoulder imbalance is an independent risk factor for upper extremity skeletal muscle asymmetry.

Background. Pose estimation based on deep learning has been expected to be a breakthrough method to increase the accuracy of clinical photographic evaluation and to decrease interobserver errors. The purpose is to quantify pose estimation from photography of patients with adolescent idiopathic scoliosis (AIS) using open-source software packages and determine correlations between parameters obtained by radiography and photography. Methods. We included 12 consecutive patients with AIS treated with spinal correction surgery. Photographs were taken preoperatively using a tripod-mounted camera (iPhone 13Pro) on an X-ray tube head. To assess photographic parameters obtained by photography, we defined 17 points to analyze posture and define parameters. Results. In the sagittal plane, there was a significant correlation between the radiographic trunk tilt angle and the photographic sagittal trunk tilt angle of the shoulder–hip and ear–hip. In the coronal plane, there was a significant correlation between the radiographic clavicle angle and the photographic shoulder height angle, and the radiographic C7–CSVL and the photographic coronal trunk tilt angle. Conclusions. Posture analysis by photography using popular mobile devices has clinical utility for improving and promoting the screening and early detection of AIS because it is simple, without patient exposure to X-ray radiation.

Introduction: The differential diagnoses of lumbar spinal stenosis (LSS) and adult spinal deformity (ASD) have been demonstrated primarily using sagittal radiographic spinopelvic parameters. However, it is more important to know the differences in the characteristic clinical symptoms to make accurate treatment decisions. Recently, the relationship between spinal disease and Locomotive Syndrome (LS) has been reported. Additionally, the Geriatric Locomotive Function Scale-25 (GLFS-25) was reported to be a useful scale to evaluate disease severity and characteristic clinical symptoms in spinal disease. Methods: Sixty-nine consecutive patients with ASD and 196 patients with LSS who underwent spinal surgery were included. Locomotive dysfunction was evaluated using the GLFS-25 questionnaire and physical performance tests including the two-step test and the stand-up test, measured preoperatively. The correlations between sagittal spinopelvic parameters of ASD and LS were examined. Results: All subjects with lumbar degenerative disease in the present study were diagnosed with LS preoperatively. The severity of LS in patients with LSS and ASD were statistically similar. GLFS-25 scores in the mobility and community domain were similarly poor in both groups. Several scores in the domestic life and self-care domains were significantly worse in the ASD group. Question 20 of the GLFS-25, related to load-bearing tasks and housework, was significantly associated with a large pelvic incidence in ASD patients. Conclusions: Lumbar degenerative disease requiring surgery severely affects the LS of older people. ASD patients had more difficulty with load-bearing tasks and housework such as cleaning the yard, carrying heavy bedding, dressing, and bathing compared to LSS patients.