[A treatment principle with questionable effectiveness in Perthes disease]

Area of Science:

• Orthopedics
• Biomechanics
• Pediatric Orthopedics

Context:

• Conservative treatment for Perthes disease often aims to reduce hip joint forces.
• Existing splints, like the Thomassplint, are considered clinically insufficient for effective force reduction during weight-bearing.
• The impact of splints on hip joint forces during the non-weight-bearing (swinging) phase remains under-investigated.

Purpose:

• To investigate the forces on the hip joint during the swinging phase of the leg while using a splint.
• To analyze the biomechanical effects of splints on hip joint loading during non-weight-bearing ambulation.
• To evaluate the efficacy of splints in reducing hip joint forces in the context of Perthes disease treatment.

Summary:

• This study utilized a simplified mechanical model to analyze hip joint forces during the swinging phase with splint use.
• Results indicate that splints significantly increase hip joint forces compared to physiological forces during the swinging phase.
• These elevated forces, occurring during hip flexion, exert pressure on the vulnerable ventro-cranial femur head, often affected in Perthes disease.

Impact:

• The findings challenge the biomechanical principle of using splints to reduce hip joint forces in Perthes disease.
• Suggests that splints may exacerbate joint loading in critical areas, potentially harming the femoral head.
• Recommends reconsidering and potentially abandoning the use of splints for hip joint force reduction in Perthes disease treatment.