Shock wave therapy for femoral head necrosis—Pressure measurements inside the femoral head

Abstract

There is a persisting need for effective therapies of femoral head necrosis, a common bone disease. Promising clinical results have been stated for the treatment with extracorporeal shock waves (ESW). However, the effective remaining pressure in the target region inside the femoral head has never been determined. Aim of this study was to investigate whether ESW are able to propagate through bone without an excessive loss of pressure. The remaining ESW pressure generated by an electromagnetic device after passing a certain intraosseous distance within the femoral head was measured. Standardized holes were drilled in porcine femora and the absorption in relation to reference measurements in degassed water was determined. The results showed continuous attenuation of shock waves in bone. After a clinical relevant intraosseous distance of 10 mm an ESW pressure of ∼50% remained. In conclusion, ESW have the potential to reach necrotic regions with therapeutic pressure levels and to effectively treat femoral head necrosis.