Longitudinal Changes in Lower Extremity Alignment and Mechanical Axis Parameters After Bariatric Surgery in Patients With Morbid Obesity: A Prospective Observational Study

The goal of this prospective observational study is to understand whether major weight loss after bariatric surgery is associated with changes in the alignment of the lower limbs in adults with morbid obesity. The hips, knees, and ankles form a connected weight-bearing system that supports the body during standing and walking. The position of these joints in relation to one another affects how body weight and mechanical forces are transmitted through the legs. In people with severe obesity, increased body weight and changes in body shape may influence the way these forces are distributed across the lower extremities. Bariatric surgery can result in substantial weight loss. However, it is not yet fully understood whether this degree of weight reduction is accompanied by measurable changes in the alignment of the hips, knees, and ankles or in the mechanical axis of the lower limbs. This study will follow patients undergoing bariatric surgery and will evaluate them before surgery and again at approximately 3, 6, and 12 months after surgery. The study is observational. This means that researchers will observe and measure changes that occur during the patients' clinical course rather than assigning participants to a particular treatment for research purposes. The main question is whether lower-extremity alignment and mechanical-axis measurements change during the first year after bariatric surgery as patients lose weight. "Lower-extremity alignment" describes how the hip, knee, and ankle are positioned in relation to one another. The "mechanical axis" is an imaginary weight-bearing line used in orthopedics to describe how forces are transmitted through the leg from the hip toward the ankle. The position of this line in relation to the knee helps doctors understand how weight and mechanical forces are distributed across the lower limb. Researchers will examine radiographic measurements that describe the overall relationship between the hip, knee, and ankle and the c