Hip Imaging and Injections

Intra-articular corticosteroids associated with increased risk of total hip arthroplasty at 5 years

BACKGROUND

Intra-articular corticosteroid injections are commonly administered for hip pain. However, guidelines are conflicting on their efficacy, particularly in patients without arthritis. This study assessed for an association of corticosteroid injections and the incidence of total hip arthroplasty at 5 years.

METHODS

Patients with a diagnosis of hip pain without femoroacetabular osteoarthritis who were administered an intra-articular corticosteroid injection of the hip within a 2-year period were identified from the Mariner PearlDiver database. Patient were matched to patients with a diagnosis of hip pain who did not receive an injection. 5-year incidence of total hip arthroplasty was compared between matched patients who received an intra-articular corticosteroid injection and those who did not.

RESULTS

2,540,154 patients diagnosed with hip pain without femoroacetabular arthritis were identified. 25,073 (0.9%) patients received a corticosteroid injection and were matched to an equal number of control patients. The incidence of total hip arthroplasty (THA) at 5-year-follow up was significantly higher for the corticosteroid cohort compared to controls (1.1% vs. 0.5%; p < 0.001). The incidence and risk of THA increased along with number of injections (1 injection: 0.8%, OR 1.37; 95% CI, 1.34-1.42; p < 0.001, 2 injections: 1.1%; OR 1.45; CI, 1.40-1.50; p < 0.001, ⩾3 injections: 1.5%; OR 1.48; CI, 1.40-1.56; p < 0.001).

CONCLUSIONS

There may be a dose-dependent association of corticosteroid injections and a greater risk of total hip arthroplasty at 5 years. These results along with the conflicting guidelines on the efficacy of intra-articular steroids for hip pain should prompt physicians to consider osteoarthritis progression that may occur in the setting of corticosteroid injections in non-arthritic hips.

Measurement of pelvic tilt and rotation on AP radiographs using HipRecon: Validation and comparison to other parameters

In this paper, we present and evaluate HipRecon, a noncommercial software package that simultaneously calculates pelvic tilt and rotation from an anteroposterior pelvis radiograph. We asked: What is the (1) accuracy and precision, (2) robustness, and (3) intra-/interobserver reliability/reproducibility of HipRecon to analyze both pelvic tilt and rotation on conventional AP pelvis radiographs? (4) How does the prediction of pelvic tilt on AP pelvis radiographs using HipRecon compare to established measurement methods? We compared the actual pelvic tilt of 20 adult human cadaveric pelvises with the calculated pelvic orientation based on an AP pelvis radiograph using HipRecon software. The pelvises were mounted on a radiolucent fixture and a total of 380 AP pelvis radiographs with different configurations were acquired. In addition, we investigated the correlation between actual tilt and the tilt calculated using HipRecon and seven other established measurement methods. The calculated software accuracy was 0.2 ± 2.0° (-3.6-4.1) for pelvic tilt and 0.0 ± 1.2° (-2.2-2.3, p = 0.39) for pelvic rotation. The Bland-Altman analysis showed values that were evenly and randomly spread in both directions. HipRecon showed excellent consistency for the measurement of pelvic tilt and rotation (intraobserver intraclass-correlation coefficient [ICC]: 0.99 [95% CI: 0.99-0.99] and interobserver ICC 0.99 [95% CI: 0.99-0.99]). Of all eight analyzed methods, the highest correlation coefficient was found for HipRecon (r = 0.98, p < 0.001). In the future, HipRecon could be used to detect changes in patient-specific pelvic orientation, helping to improve clinical understanding and decision-making in pathologies of the hip.