Does extracorporeal shockwave therapy treat leg length discrepancy? an experimental animal study

Abstract

Extracorporeal shockwave therapy (ESWT) is widely used to treat musculoskeletal diseases, but its impact on adolescents with unhealed epiphyseal plates is concerning. It remains unclear whether ESWT applied to growth plates promotes or inhibits bone growth. Low energy ESWT does not cause damage of articular cartilage and promotes the growth of articular cartilage. Therefore, the application of ESWT to treat the leg length discrepancy is a possibleoption. Here, the 96 adolescent rats were used to demonstrate that different levels of ESWT developed different effects on the epiphyseal plate and bone growth. The effects and safety of ESWT on the epiphyseal plate were measured at different energy levels of 0.1, 0.25, and 0.5 mJ/mm² with 800 impulses, 4 Hz at the 7, 13, and 25 weeks. Additionally, the treatments promoted the growth and length of the tibia bone as the ESWT application by compared with Sham group. Notably, ESWT stimulated the expression of IL-1β at the 7 week, which then decreased by the 25 week. However, no apoptosis signals and cell death were detected, and there was no tissue damage to the epiphyseal plate. The expression of SOX9, BMP2, and BMP4 was observed in the epiphyseal plate following ESWT, suggesting a role in promoting bone growth. Our results suggest that ESWT is a safe therapeutic modality for stimulating bone growth at the epiphyseal plate in adolescents, leading to increased bone length. This approach holds potential for future treatment of patients with leg length discrepancies.