Application of jumbo cup in acetabular revisions for patients with massive acetabular bone deficiency / 中华骨科杂志

ABSTRACT

Objective To investigate the effects of the jumbo cup in acetabular revision for patients with massive acetabular bone deficiency.Methods We retrospectively studies 48 patients (49 hips) who underwent jumbo cup revisions between 2006 and 2015 (19 men and 29 women;average age62± 12 years).The acetabular bone defects were classified according to Paprosky classification (Paprosky Ⅱ 27 hips,Paprosky ⅢA 18 hips,Paprosky ⅢB 4 hips).Radiological assessments were conduced to evaluate the acetabular prosthesis loosening,dislocation and infection.The reasons for revisions were mechanical loosening in 41 cases,and infections in another 8 cases with cement spacer putted by last surgery.Results The operation duration and blood loss was 110 min (85-160 min) and 315 ml (270-455 ml) respectively.After an average follow-up of 6.8 years (1-11 years),Harris hip score was increased from 47.6±7.1 preoperatively to 82.4± 6.2 postoperatively.Osseointegration occurred in the acetabular components at 6 months postoperatively.Radiograph analysis showed satisfied position of acetabular cup without complications such as damages of vessels or nerves.The successful rate of jumbo cup revisions was 89.8％±4.4％.However,two in Paprosky ⅢA failures for periprosthetic infection occurred and two in Paprosky ⅢA,one in Paprosky ⅢA and the other in Paprosky ⅢB for acetabular component loosening.One patient in Paprosky ⅢB had weight-bearing pain and relieve slightly after conservative treatment.The radiologic study showed that there was no relationship between failure rate and acetabular abduction angle (r=0.06,P=0.53),rotation center migration in vertical direction (r=0.11,P=0.14) and horizontal direction (r=0.04,P=0.89).Conclusion The mid-term results show that using jumbo cup in revising acetabular failure with massive bone deficiency are optimal,which can be achieved by simplified operation procedures,reduction in the need of bone graft and promotion in acetabulum osseointegration.However,higher failure rate may occur in Paprosky ⅢB patients.