The following is a summary of “Head and pelvis are the key segments recruited by adult spinal deformity patients during daily life activities,” published in the September 2024 issue of Rheumatology by Ayoub et al.

Functional assessment plays a crucial role in evaluating patients with adult spinal deformity (ASD). However, various 3D kinematic parameters from movement analysis can often confuse spine surgeons. Understanding these patterns is essential for effective treatments. 

Researchers conducted a prospective study investigating patients’ movement patterns with ASD by examining key kinematic parameters. 

They analyzed 115 patients with ASD and 36 controls using biplanar radiographs and 3D movement analysis while walking, transitioning from sitting to standing, and climbing stairs. This analysis helped calculate joint and segment kinematics. Principal component analysis was then used to identify the most relevant kinematic parameters that define the movement strategies adopted by patients with ASD. 

The results showed that pelvis and head relative to pelvis kinematics were the most significant parameters. Patients with ASD exhibited 4 distinct movement strategies classified into different classes. Class 1 had normative head and pelvis kinematics, Class 2 displayed persistent pelvic backward tilt, Class 3 had persistent forward shift of the head, and Class 4 exhibited both pelvic backward tilt and forward head shift. Patients in classes 3 and 4 demonstrated sagittal malalignment on static radiographs, with increased pelvic tilt, pelvic incidence-lumbar lordosis mismatch, and sagittal vertical axis. Interestingly, those in class 3 maintained normal pelvic kinematics during movement, underscoring the importance of functional evaluation. The head and pelvis were identified as critical segments in maintaining static global posture while defining movement patterns. 

Investigators concluded by emphasizing the significance of functional assessment in understanding movement strategies among patients with ASD, revealing distinct patterns that may influence treatment approaches. 

Source: nature.com/articles/s41598-024-70038-w