Treatment of Recurrent Dislocation after Total Hip Arthroplasty Using Advanced Imaging and Three-Dimensional Modeling Techniques: A Case Series

Abstract

Background: Surgical treatment options for addressing recurrent dislocation after total hip arthroplasty (THA) vary. Identifying impingement mechanisms in an unstable THA may be beneficial in determining appropriate treatment. Questions/Purposes: We sought to assess the effectiveness of developing pre-operative plans for treating hip instability after THA. We used advanced imaging and three-dimensional modeling techniques to perform impingement analyses in patients with unstable THA. Methods: We evaluated a series of eight patients who would require revision THA to treat recurrent dislocation. Using a preoperative algorithmic approach, we built patient-specific models and evaluated hip range of motion with computed tomographic scanning and biplanar radiography. This information was used to determine a surgical treatment plan that was then executed intra-operatively. Patients were followed for 2 years to determine whether they experienced another hip dislocation following treatment. Results: Pre-operative kinematic modeling showed four of the eight patients had limited hip range of motion during flexion and internal rotation; a prominent anterior inferior iliac spine (AIIS) was found to limit hip range of motion in some of these cases. In the other four patients, range of motion was acceptable, suggesting soft-tissue causes of dislocation. No patients in this series experienced dislocation after undergoing revision THA. Conclusion: Advanced modeling techniques may be useful for identifying the impingement mechanisms responsible for instability after THA. Once variables contributing to limited hip range of motion are identified, surgeons can develop treatment plans to improve patient outcomes. Resecting a hypertrophic AIIS may improve hip range of motion and may be an important consideration for hip surgeons when revising unstable THAs.

Pelvic morphologies of developmental dysplasia and primary osteoarthritis on range of motion after total hip arthroplasty

“…It has been reported that THA for secondary osteoarthritis due to DDH exhibits a high dislocation rate 4,5 . Bone impingement at the AIIS after THA can be a cause of dislocation 8–10 . We proposed that pelvic morphology, including AIIS, with DDH could affect the ROM after THA.…”

“…4,5 Bone impingement at the AIIS after THA can be a cause of dislocation. [8][9][10] We proposed that pelvic morphology, including AIIS, with DDH could affect the ROM after THA. Compared with the position of the AIIS in the pOA, the position of the AIIS in the DDH protrudes more medially and cranially from the TD, which causes an increase in ROM.…”

“…The anterior inferior iliac spine (AIIS) is a known site of bony impingement and causes dislocation during flexion and internal rotation after THA 8–10 . A previous simulation study revealed that an AIIS overhanging caudal to the acetabular rim significantly decreases the range of motion (ROM) for flexion and internal rotation 9 .…”

“…The anterior inferior iliac spine (AIIS) is a known site of bony impingement and causes dislocation during flexion and internal rotation after THA. [8][9][10] A previous simulation study revealed that an AIIS overhanging caudal to the acetabular rim significantly decreases the range of motion (ROM) for flexion and internal rotation. 9 Another simulation study reported that the distance between the center of the head and the AIIS after THA will influence the range of flexion and internal rotation.…”

Imaging in Hip Arthroplasty Management Part 2: Postoperative Diagnostic Imaging Strategy

“…Concerning dual mobility cup, dislocation can be of two types: a loss of contact between the PE insert covering the head and the acetabular piece (classical) or an intra-prosthetic PE dislocation [ 84 ], defined as a loss of contact between the head and the PE. The latter can occur during the reduction of a classical dislocation in the early setting and lately secondary to wear [ 85 ] ( Figure 16 ).…”