No Difference in Dislocation Rates Comparing DMC-THA for Displaced Femoral Neck Fracture and for Osteoarthritis-A Matched-Pair Analysis.

BACKGROUND

We hypothesized the risk of prosthetic instability would be similar in patients treated for femoral neck fracture (FNF) comparatively to patients treated for osteoarthritis (OA) using a dual-mobility cup-total hip arthroplasty (DMC-THA).

METHODS

One hundred and nine patients (109 hips), with a mean age of 69.6 ± 3 years (65-75 years), underwent DMC-THA using a posterolateral approach for a FNF (study group). Patients were matched for age and sex with 109 OA patients treated by the same procedure (control).

RESULTS

Postoperatively, there were four dislocations of the large articulation in the study group, and none in the control ( = 0.12). Periprosthetic joint infection (PJI) was the most common surgical complication and was more frequent in the study group. Postoperatively, functional results were at least good in > 90% patients in both groups. At the last follow-up, patients in the study group had recovered autonomy and physical activity comparable to those of the preoperative period.

CONCLUSION

We found no increased risk of dislocation after DMC-THA using a posterolateral approach for FNF as compared to the same procedure for OA. In this study, function and independence were restored postoperatively in the vast majority of patients. DMC-THA appears as a viable therapeutic option in autonomous patients with a displaced FNF.