Anterior acetabular coverage and femoral head–neck measurements predict postoperative anterior impingement: A simulation study

Abstract

The aim of this simulation study was to evaluate the relationship of elements of anterior acetabular coverage and femoral head–neck shape with the occurrence of postoperative anterior impingement after curved periacetabular osteotomy (PAO). Sixty‐two patients with symptomatic developmental dysplasia of the hip who had undergone curved PAO were selected. The likelihood of developing postoperative anterior impingement was explored through simulations of the range of motion by collision detection of the pelvis and femur. Postoperative anterior impingement was defined as impingement that occurred during postoperative bone flexion <105° or postoperative internal rotation <20° at 90° flexion. The three‐dimensional center‐edge (CE) angles, acetabular and femoral versions, radiographic alpha angles of the femoral head, combination angles of anterior CE and alpha angles, and combined anteversions of acetabular and femoral versions were compared between patients with postoperative anterior impingement and nonimpingement. A receiver operator characteristic (ROC) analysis was conducted to determine thresholds of the examined radiographic parameters and calculate their accuracy for predicting postoperative anterior impingement. A multivariate analysis was performed to test whether combined anteversion, anterior CE angle, and combination angle are associated with excellent modified Harris Hip Scores (mHHSs). ROC analysis demonstrated a combination angle ≥108° was predictive of the occurrence of postoperative anterior impingement after curved PAO, which can lead to impaired clinical outcomes. Conversely, a combination angle <108° was significantly associated with mHHS ≥ 90 points. To avoid postoperative anterior impingement, osteochondroplasty of the femoral head or anterior CE angle control should be performed for patients with preoperative combination angles ≥90°.

Relative Acetabular Retroversion and Its Association With Earlier-Onset Symptomatic Osteoarthritis of the Hip

“…Similarly, our study's findings indicate that individuals with a relatively retroverted acetabulum are at an increased risk of experiencing an earlier onset of hip OA [ 25 ]. Although numerous studies attempt to describe the relationship of femoral and acetabular version and mechanics with various pathologies, there are little data directed specifically at the age- and gender-dependent effects of acetabular anteversion on OA of the hip [ [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] ]. Based on this information, younger male patients presenting with hip pain may have an underlying cause that could warrant surgical intervention sooner than expected.…”

“…Furthermore, it is worth mentioning that factors like femoral version or the combined version (ie, McKibbin Instability Index), which were not taken into account in this study, could potentially offer an additional layer of insight into how these patients may present with hip OA at a younger age. Several studies postulate that those with an increased or decreased acetabular version demonstrate a reciprocal change in the femoral version to maintain a combined version within normal parameters [ 8 , 9 , 12 , 22 ]. On the other hand, data collection on the femoral side could have provided further insight into why certain patient groups present older or younger with symptomatic hip OA.…”

“…The prevalence of hip OA is continuously rising due to an aging population and obesity, with the average total hip arthroplasty (THA) patient in the United States approximately 65 years of age [ 2 ]. Although the etiology of primary OA of the hip is not fully understood, several research studies have suggested a relationship between abnormal hip biomechanics and hip OA, particularly in terms of femoral neck anteversion, acetabulum anteversion (AA), developmental dysplasia of the hip, and femoroacetabular impingement [ [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] ]. It has been stipulated that the posterior and superior aspects of the acetabulum are subject to high loads during activities of daily living and normal gait [ 15 ].…”