[Application of all-coated long stem prosthesis associated with allograft in revision total hip arthroplasty].

Objective: To study the effect of all-coated long stem prosthesis associated with allograft in revision total hip replacement (THR).

Methods: From January 1997 to January 2004, 20 patients with non-infectious loosened implant after primary THR were treated. There were 12 males and 8 females with a mean age of 65 years (58-77 years). The average period between primary THR and revision THR was 12 years (3-18 years). According to classification of Paprosky, there were 10 cases of type II, 6 cases of type IIIA, 3 cases of type IIIB and 1 case of type IV. All-coated long stem prosthesis was used in all cases. Impacting bone grafting was done in 12 cases and impacting bone grafting associated with cortical strut grafting in 8 cases. The mean amount of morselized bone was 20 g (5-35 g), the length of cortical bone was 10-22 cm.

Results: All the incisions got healing by first intension. All patients were followed up for an average period of 36 months (16-48 months). Dislocation occurred at 5 days after operation and was cured with closed reduction and traction in 1 case. There was significant difference (P < 0.05) in the mean Harris score between preoperation (50.0 +/- 2.3) and postoperation (90.0 +/- 2.5). The X-ray checking showed that continuous radiolucent line of 3 mm occurred in 1 case, prosthesis subsidence of 5 mm and 7 mm in 2 cases and that no bone absorption was observed. Seven cases of cortical bone grafting union was achieved within 3 years except 1 case of cortical bone un-union.

Conclusion: It can obtained the initial stabilization of prosthesis to use all-coated long stem prosthesis associated with allograft in revision THR to treat femur bone defect after THR. The short-term effects of the clinical and X-ray checking are satisfactory, but future effect is to be observed.