Computer-Assisted Navigation for Complex Revision of Unstable Total Hip Replacement in a Patient With Post-traumatic Arthritis.

Imageless computer-assisted navigation (CAN) excels in the post-traumatic arthritis and complex revision case setting when altered anatomy and landmarks are inaccurate references for cup positioning. We describe the case of an adult male patient who suffered an acetabular fracture which was treated nonoperatively. He subsequently developed post-traumatic arthritis and underwent an anterior approach total hip arthroplasty 25 years later. Postoperatively, he developed recurrent hip instability due to malpositioned components. We describe the use of imageless CAN during revision total hip arthroplasty to correct malpositioned components, with 3-year follow-up without dislocation. In these complex cases, CAN reduces the risk of component malpositioning and joint instability.