Artroplastia total de cadera en pacientes con artritis reumatoide y protrusión acetabular: Utilización de injerto óseo

background: in 36% of the patients with rheumatoid arthritis (ra) the hip joint is affected, while 5% additionally present protrusio acetabuli (pa). if the socket is medially positioned, it may lead to failure in the long-term. methods: we performed 48 total hip arthroplasties (tha) in patients with ra, of which 8 (16%) presented protrusio acetabuli (pa). all were women, average age: 60 years, and 3.8 years median follow-up. all the sockets were cemented, and morselized bone graft was used in 6 cases while in 2 the graft was cut in slices. results: there was an improvement in the hip score, from 51 to 81 points pop. osseointegration of the bone graft ensued in all cases. the joint center of rotation was lateralized from 16 to 21 mm on average, and lowered from 31 to 23 mm. there were 2 non-unions of the greater trochanter, 1 greater trochanter fracture, one superficial infection, and one socket loosening which had to be revised with an uncemented implant that and achieved a satisfactory result. conclusions: the pa in ra progresses 2 mm/year in the supero-medial direction. the treatment with cancellous bone graft and cemented acetabular cup, has proved successful. in this type of arthroplasties the lateralization of the center of rotation is key for long-term success. in our series, osseointegration and remodeling of the bone graft occurred in all cases, with good results.