Combination of Anterior Acetabular Coverage and Femoral Head Shape Predicts Femoroacetabular Impingement After Periacetabular Osteotomy

Work productivity after periacetabular osteotomy was affected by preoperative progression of osteoarthritis and heavy workload

INTRODUCTION

Many patients who have undergone a periacetabular osteotomy (PAO) for developmental dysplasia of the hip (DDH) have had jobs preoperatively. Postoperative return to work and work productivity are important for livelihood security and the social economy. However, there is a lack of evidence on work productivity after PAOs. Therefore, this study investigated the return to work rates and influence of workload, clinical, and radiographic parameters on work productivity after a curved PAO.

MATERIALS AND METHODS

In this study, the data of 68 hip joints among 48 participants who underwent curved PAO for symptomatic DDH were analyzed. Correlations between postoperative work productivity and clinical, radiographic, and workload parameters were assessed. Work productivity was evaluated using the Work Productivity and Activity Impairment (WPAI) questionnaire. Clinical factors were assessed using the modified Harris Hip Scores (mHHS) and University of California, Los Angeles Activity scores. Preoperative and postoperative radiographic parameters were compared with postoperative work productivity. The workload was categorized using the Reichsausschuß für Arbeitszeitermittlung (REFA)-classification system.

RESULTS

Of the participants, 98% returned to work and 87.5% returned to their original jobs. Work productivity was significantly improved in all workload categories at the 1-year postoperative follow-up. Multivariate analysis demonstrated that preoperative Tönnis and REFA classification grades were significantly associated with the postoperative WPAI.

CONCLUSION

Curved PAOs can improve postoperative work productivity and return to work rates. Preoperative progression of osteoarthritis and heavy workload affect postoperative work productivity.

Risk factors for lateralization or superiorization of the center of the femoral head in eccentric rotational acetabular osteotomy

PURPOSE

This study aimed to clarify the factors that cause the lateralization and superiorization of the femoral head after eccentric rotational acetabular osteotomy (ERAO) by examining the three-dimensional morphology of the osteotomy site using computed tomography (CT).

METHODS

This study included 52 patients who underwent ERAO for hip dysplasia. Postoperatively, the center of the femoral head was measured for lateralization and superiorization. We defined the iliac and sciatic osteotomy angles in the coronal and axial CT planes, respectively. The surgical factors for lateralization and superiorization were analysed using multiple logistic regression analysis. We also analysed the relationship between the femoral head relocation and clinical outcomes (as assessed using Japanese Orthopaedic Association (JOA) scores).

RESULTS

Thirty-five patients had hips with lateralized femoral heads, and 25 patients' femoral heads were superiorized. Logistic regression analysis revealed that a higher osteotomy angle of the ilium in the coronal plane served as a significant predictor of superiorization of the femoral head. Similarly, a larger osteotomy angle of the ischium in the axial plane and the amount of change in the lateral centre edge angle were identified as predictors of lateralization. A weak negative correlation was observed between the amount of lateralization and the JOA score.

CONCLUSION

Large osteotomy angles in the superior and posterior aspects of the acetabulum carry a risk of superiorization and lateralization of the center of the femoral head. Surgeons should be aware of the need to chisel through the internal plate to achieve the results described in the ERAO theory.

STUDY DESIGN

A single-center, retrospective study.

Combined assessment of acetabular coverage and femoral head-neck shapes predicts osteoarthritis progression after periacetabular osteotomy

INTRODUCTION

Postoperative osteoarthritis (OA) progression is a major determinant of failure after curved periacetabular osteotomy (CPO). A large postoperative combination angle, i.e., the combination of computed tomography-based anterior center edge and alpha angles, is associated with femoroacetabular impingement after CPO, but its association with postoperative OA progression is unclear. We aimed to identify the anatomical parameters that can lead to OA progression after CPO and the impact of the combination angle on the same.

MATERIALS AND METHODS

We included 90 hips that were subjected to CPO at our center between March 2013 and March 2018. Seventeen hips showed OA progression with an increase in the Tönnis classification after surgery; 73 hips showed no progression. Radiographic anatomical parameters, including the lateral and anterior center edge angles, femoral and acetabular anteversion, and combination angle, and clinical outcomes, including modified Harris Hip Scores (mHHSs), postoperative anterior impingement, and range of motion, were compared between the two groups. Statistical significance was set at P < 0.05.

RESULTS

Postoperative OA progression was significantly affected by preoperative OA evidence (P = 0.017), acetabular anteversion < 5.0° (P = 0.003), and a combination angle > 107.0° (P = 0.025). Patients with radiographic OA progression were associated with poor mHHSs (P = 0.017) and high frequencies of anterior impingement with a limited hip flexion and internal rotation angle.

CONCLUSIONS

OA progression after CPO may be associated with preoperative evidence of OA and postoperative acetabular retroversion as well as a large combination angle. Surgeons should focus on the potential effects of preoperative OA grades, postoperative reduction in acetabular anteversion, and postoperative combination angle.

Arthroscopy Confers Favorable Clinical Outcomes in Asian Patients with Borderline Developmental Dysplasia of the Hip

OBJECTIVE

Hip arthroscopy has recently appeared as a successful therapy in treating borderline developmental dysplasia of the hip (BDDH). This study aimed to describe the minimal 2-year follow-up after hip arthroscopy for patients with BDDH in the Asian population and use the combination of lateral center edge angle (LCEA) and alpha angles to detect the appearance of impingement in the BDDH population.

METHODS

This retrospective investigation was conducted utilizing information from arthroscopically treated BDDH patients in 2018 and 2019. The following patient-reported outcomes were reported: modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living, International Hip Outcome Tool 12-component form, and Visual Analog Scale. We also considered the clinical data regarding radiological measurements, intraoperative findings, interventions, complications, and subsequent surgical revisions, in the analysis of combination angles in detecting the occurrence of impingement. Patients with asymptomatic contralateral hips from traumatic hip injury (pelvic fracture) served as the control group. A 2:1 propensity score matching was based on age, sex, and BMI. A receiver operating characteristic curve (ROC) was used to identify the thresholds of combination angles and their accuracies.

RESULTS

A total of 77 hips met the inclusion and exclusion requirements. After the follow-up period, most patients showed a considerable improvement in patient-reported outcomes compared to their preoperative values (P < 0.001 for all). The overall rate of complications was 5.2%, whereas the rate of revisions was 3.9%. Increasing preoperative alpha angle age was significantly positively correlated with improving patient-reported outcomes. The combined angle cut-off was determined to be 80.5° (AUC, 0.858; 95% CI: 0.757-0.938; sensitivity (SE), 98.1%; specificity (SP), 74.1%; P < 0.001) for the occurrence of impingement in BDDH population.

CONCLUSION

Good patient-reported outcomes and low revision rates can be expected in the BDDH population with careful selection of patients in Asian populations. A combination angle >80.5° could be a reliable predictive factor of impingement in BDDH populations.

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

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°.