THA in AS patients can be technically demanding, especially in patients with an ankylosed hip. Problems relate to positioning of the patient, femoral neck cut, original joint line identification, acetabular component positioning, and adequate release of soft tissues.

This is a very demanding procedure.AS is a disease of the whole organism which makes more probable complications, especially when done bilaterally. As far as the local tips are concerned I always prefer lower neck cut and long necks to oppose the effect of ectopic ossifications that are more common in AS patients.

Thank you, Panayot for your experienced opinion.

I agree with both of you that this is very demanding procedure, specially if you do it bilateral simultaneously. Hip involvement in patients with AS is very high 30-50%, and 90% bilateral. Problem relate to instalation in op. table, specially for bilateral simultaneousTHR, Heterotopic ossifications are higher in AS patients with bilateral THR.

I agree

I never do Bilateral Hip arthoplasty  in my life of 25 years of practise in Orthopedics. The soft tissue injury and subsequent bleeding and Blood loss could be fatal .I routinely give Indomethcin from 2 nd post operative period for 6 wks , and dislocation rate is more Long neck might increase that chance .egarding early mobilation I do not allow befoe 5 daysbut patient can do exercises on bed from day 2

With improvements in surgical techniques, implants design and pre and post op. care it is possible early mobilization. Early mobilization decrease the incidence of deep venous thrombosis, pulmonary embolism, atelectasis, pneumonia and urinary retention.

Post op xrays re good

Early weight bearing and NSAID to minimise hetero trophic ossification