Background: This retrospective study investigated the clinical efficacy of individual extracorporeal shockwave treatment (IESWT) for early stage osteonecrosis of the femoral head (ONFH).
Material and methods: The study included 56 patients (89 hips) with 28 patients (46 hips) in the IESWT group and 28 patients (43 hips) in the conventional ESWT (CESWT) group. The ONFH was caused by the use of steroids, trauma and alcohol consumption. The IESWT focal point was from the front of the femoral head and the exposed necrotic tissue in 3D environment was guided by simulation software. The CESWT focal point was the side of the femoral head and guided by MRI and X‑ray imaging. The evaluation standards included VAS score, Harris hip score (HHS), necrosis volume and healing rate.
Results: For the healing rate the results were 66.67% were improved, 21.43% unimproved and 11.90% aggravated in the CESWT group and 77.78% improved, 17.78% unimproved and 4.45% aggravated in the IESWT group. Statistically significant differences were observed in the healing rate between the two groups (P < 0.05). This retrospective study demonstrated that the healing rate for IEWST was higher than for CEWST. There were no statistically significant differences in the VAS score and the HHS between the two groups (P > 0.05). The effects of pain relief and functional recovery were not obvious and according to our clinical experience this may be due to a short clinical observation time where a longer time might result in better clinical results. Statistically significant differences were observed in the necrosis volume after 18 months between the 2 groups (P < 0.05) and implied that IESWT can significantly reduce the volume of necrosis. The volume after 18 months in the IESWT group was significantly improved compared with baseline (P < 0.05).
Conclusion: The use of IESWT can significantly reduce the necrosis volume. No complications were found.
Keywords: Function; Magnetic resonance imaging; Necrosis; Pain; Retrospective study.