Experience with external fixation devices during preoperative preparation and planning of primary and revision hip arthroplasty in complicated cases of rigid hip deformity

Objective To review external fixation used at preparation stage of primary and revision hip arthroplasty in complicated cases of rigid hip deformity to optimize patient outcomes. Material and methods Outcomes of 15 patients with considerable limb length discrepancy of lower limbs were reviewed. Shortening of 7 to 10 cm was observed in ten cases, and five had 5-to-7-cm discrepancy. All patients underwent two-staged surgical treatment including Ilizarov external fixation at the first stage followed by total hip replacement at the second phase. The external fixator was taken off at the end of distraction on the day of implant placement. The patients were followed up within 29 ± 17 months on average and maximum 57 months of two-staged surgical treatment. Results The Harris hip score measured 21 ± 9 prior to external fixation and 77 ± 13 after arthroplasty. The usage of external fixation allowed for limb length equalization in all the cases adapting soft tissues for the next arthroplasty surgery. No infection was reported. Four of fifteen patients developed dislocation of the prosthetic head (3 early and 1 delayed dislocations); two patients underwent closed reduction and another two had a revision arthroplasty to stabilize the joint. Conclusion External fixation devices used at preparation stage of primary and revision hip arthroplasty can be advocated for complicated rigid hip deformity to recover supportability of the leg, equalise limb length, adapt soft para-articular tissues, realign the centre of rotation and improve treatment outcomes.