The favorable outcome of Bernese periacetabular osteotomy for the hip osteoarthritis in multiple epiphyseal dysplasia.

BACKGROUND: Multiple epiphyseal dysplasia (MED) is a rare congenital bone dysplasia. Patients with MED develop secondary hip osteoarthritis as early as the third to the fourth decade. Currently, there is no consensus on the prevention of the progressive hip osteoarthritis secondary to MED. The Bernese periacetabular osteotomy (PAO) is a joint-preserving surgery to reshape acetabulum and extend femoral head coverage. However, there is no documentary evidence for the effect of the procedure on MED hips. PATIENTS AND METHODS: We analyzed the preliminary outcomes following the Bernese PAO in 6 MED hips. The average age at the time of surgery was 14.3 years (range from 11.4 to 17.2 years). For our study interest of time efficiency, radiographic parameters were analyzed preoperatively and 1 year postoperatively. The hip function was evaluated by the Harris Hip Score (HHS) before and after surgery. RESULTS: The mean follow-up time was 1.7 years. The mean lateral center-edge angle increased from 3.8° to 47.1° (p = 0.02), anterior center-edge angle increased from 7.3° to 35.1° (p = 0.02), and acetabulum index decreased from 27.8° to 14.6° (p = 0.04). The femoral head coverage ratio increased from 66.8% to 100% (p = 0.02). The post-operative anteroposterior pelvic radiograph demonstrated all preoperative broken Shenton lines were reversed. The mean HHS improved from 67.3 to 86.7 (p = 0.05). CONCLUSION: Bernese PAO is a feasible treatment for hip disorders in MED patients. It reshapes acetabular and femoral morphology efficiently. In our study, the preliminary results showed the procedure not only improved radiographic outcomes but also hip function.

Long-term results of Bernese periacetabular osteotomy using a dual approach in hip dysplasia.

We report the long-term results of Bernese periacetabular osteotomy using a dual approach in hip dysplasia. Fifty-three hips (49 patients, mean age 39.9 years: 13-62 years; bilateral hips: four patients) that underwent periacetabular osteotomy using a dual approach (combined Smith-Peterson and Kocher-Langenbeck techniques) between May 1997 and December 2005 were analyzed in this study. The clinical and radiologic outcomes and complications were analyzed and the final survival rates of the operated hips were investigated with survival analysis curves. Forty-nine hips survived until the final follow-up without arthroplasty, and four hips underwent arthroplasty. The average follow-up period was 11.5 years (8-16 years). The pain visual analogue scale improved from 6.3 to 1.1, while the Harris hip score improved from 61.9 to 91.1. Radiologic findings showed that all cases showed improvements in the center edge angle, acetabular angle, acetabular depth, and femoral head coverage. Two patients underwent intraarticular osteotomy due to a complication, and one patient underwent additional osteotomy due to an under-correction. Three cases showed an asymptomatic nonunion of the superior pubic ramus osteotomy site. One patient developed an avulsion fracture of the anterior superior iliac spine, and none of the cases had an infection or permanent neurologic damage. Kaplan-Meier analysis revealed that the 10-year survival rate was 93% (95% confidence interval [CI] 81-98%) with arthroplasty as the endpoint and 86% (95% CI 70-91%) with the progression of osteoarthritis based on Tönnis osteoarthritis rating as the endpoint. Based on the outcomes of a long-term follow-up of more than 10 years on average, Bernese periacetabular osteotomy via a dual approach was found to be a satisfactory method for lowering the incidence of complications while preserving hips.

Hip dysplasia in adolescence: osteotomy in childhood improves the results of periacetabular osteotomy in adolescents and young adults : a prospective study.

AIMS: Developmental dysplasia of the hip (DDH) describes a pathological relationship between the femoral head and acetabulum. Periacetabular osteotomy (PAO) may be used to treat this condition. The aim of this study was to evaluate the results of PAO in adolescents and adults with persistent DDH. METHODS: Patients were divided into four groups: A, adolescents who had not undergone surgery for DDH in childhood (25 hips); B, adolescents who had undergone surgery for DDH in childhood (20 hips); C, adults with DDH who had not undergone previous surgery (80 hips); and D, a control group of patients with healthy hips (70 hips). The radiological evaluation of digital anteroposterior views of hips included the Wiberg angle (centre-edge angle (CEA)), femoral head cover (FHC), medialization, distalization, and the ilioischial angle. Clinical assessment involved the Harris Hip Score (HHS) and gluteal muscle performance assessment. RESULTS: Significant improvements in radiological parameters were achieved in all measurements in all groups (p < 0.05). The greatest improvement was in CEA (mean of 19° (17.2° to 22.3°) in Group B), medialization (mean of 3 mm (0.9 to 5.2) in Group C), distalization (mean of 6 mm (3.5 to 8.2) in Group B), FHC (mean of 17% (12.7% to 21.2%) in Group B), and ilioischial angle (mean of 5° (2.3° to 8.1°) in Group B). There were significant improvements in the mean HHS and gluteal muscle performance scores postoperatively in all three groups. CONCLUSION: The greatest correction of radiological parameters and clinical outcomes was found in patients who had undergone hip surgery in childhood. Although the surgical treatment of DDH in childhood makes subsequent hip surgery more difficult due to scarring, adhesions, and altered anatomy, it requires less correction of the deformity and has a beneficial effect on the outcome of PAO in adolescence and early adulthood. Cite this article: Bone Joint J 2022;104-B(7):775-780.

Characteristics of the patellofemoral joint of patients with DDH and the effects of Bernese periacetabular osteotomy on the patellofemoral joint.

BACKGROUND: Some patients with developmental dysplasia of the hip (DDH) complained of anterior knee pain (AKP) before and after Bernese periacetabular osteotomy (PAO) surgery. The purpose of this study was to (1) identify the characteristics of patellofemoral joint (PFJ) deformities in patients with DDH and (2) to determine the effects of PAO on the PFJ. METHODS: Seventy patients (86 hips) were included in the DDH group. Thirty-three patients (33 knees) without AKP and hip pain were included in the control group. All patients underwent simultaneous CT scans of the hip and knee joints before PAO and after hardware removal surgery. The distance from the anterior inferior iliac spine to the ilioischial line (DAI), was measured in DDH patients. Imaging parameters of knees, including the sulcus angle (SA), femoral trochlear depth (FTD), patellar width (PW), tibial tuberosity-trochlear groove (TT-TG), patellar tilt angle (PTA) and lateral shift of the patella (LSP) were measured in patients in both the DDH and control group. TT-TG, PTA, and LSP of DDH patients were measured before PAO and after hardware removal. The DAI, PTA, LSP and TT-TG of all DDH patients before and after Bernese PAO were compared using paired t-tests. The FTD, PW, and SA of the DDH patients and the control group were analyzed using independent t-tests. PTA, TT-TG, and LSP between the control group and preoperative DDH patients, between the control group and post PAO patients were compared using independent t-tests. RESULTS: The DAI changed from 4.04 ± 0.61 mm before PAO surgery to 5.44 ± 0.63 mm after PAO surgery. The SA of the DDH group (140.69 ± 11.30 degree) was greater than that of the control group (130.82 ± 6.43 degree). The FTD and the PW of the DDH group (5.45 ± 1.59 mm, 4.16 ± 0.36 mm) were smaller than that of the control group (7.39 ± 1.20 mm, 4.24 ± 0.38 mm). The changes in LSP, PTA, and TT-TG before and after surgery were not statistically significant. Both before and after PAO, there was no statistically significant difference in the parameters of LSP, PTA, and TT-TG compared with the control group. CONCLUSION: The knee joints of DDH patients presented a certain degree of femur trochlear groove dysplasia and patellofemoral instability. PAO surgery did not change PFJ stability, although the origination point of the rectus femoris muscle moved laterally during PAO surgery.

The association the patient-reported outcomes after periacetabular osteotomy with radiographic features: a short-term retrospective study.

BACKGROUND: Bernese periacetabular osteotomy (PAO) is an effective treatment for patients with developmental dysplasia of the hip (DDH). PAO has been widely used in China, but few follow-up outcomes have been reported in the international community. Moreover, the risk factors affecting patient-reported outcomes have not been discussed in recent studies. In this study, patient-reported outcomes after PAO were reported, and risk factors affecting patient-reported outcomes were analyzed. METHODS: Patients who underwent PAO for DDH from January 2014 to January 2020 were selected as the study subjects, and 66 hips were included in the analysis after screening (59 patients, with an average follow-up time of 3.01 years). The Harris Hip Score (HHS) and International Hip Outcome Instrument-12 (iHOT-12) were used to assess hip function and patient quality of life. The changes of preoperative and latest follow-up HHSs less than 9 were defined as symptomatic hips, that is, an adverse outcome; otherwise, the score indicates preserved hips. Also, the changes of preoperative and latest follow-up iHOT-12 were defined as symptomatic hips and preserved hips. Multivariate logistic regression analysis was used to predict the risk factors influencing the patient-reported outcomes, and receiver operating characteristic (ROC) curve analysis was performed on the risk factors to determine their sensitivity, specificity and cutoff value. RESULTS: Clinical outcome analysis demonstrates marked improvements in patient-reported outcomes. The multivariate logistic regression analysis showed that when the postoperative LCEA was > 38°, adverse outcomes were much more likely. However, a Tönnis angle of - 10° to 0° was a protective factor. In addition, hips with fair or poor joint congruency were more likely to develop negative outcomes. The ROC curve analysis showed that the optimal thresholds for the LCEA and Tönnis angles used to predict outcomes after PAO were 38.2° and - 9°, respectively. Based on the results of the ROC curve analysis, among hips with poor or fair joint congruency preoperatively treated by surgeons who obtained the improper postoperative LCEAs and Tönnis angles, bad patient-reported outcomes will most likely be obtained. CONCLUSIONS: Our results demonstrate marked improvements in patient-reported outcomes. Among hips with preoperative excellent or good joint congruency treated by experienced surgeons who obtain the proper postoperative LCEA and Tönnis angles, good patient-reported outcomes can be expected.

Analysis of Factors Affecting Early Functional Recovery of Bernese Periacetabular Osteotomy.

OBJECTIVES: To explore factors affecting the efficacy of Bernese periacetabular osteotomy for the treatment of hip dysplasia. METHODS: A retrospective study was conducted on 44 patients with hip dysplasia who underwent Bernese periacetabular osteotomy with a modified Smith-Peterson approach between January 2017 and November 2019. Among them, 40 were women and four were men. The average age was 31.2 ± 9.4. Preoperative and postoperative imaging parameters were measured. The acetabular top tilt angle, lateral central edge angle, acetabular abduction angle, femoral head extrusion index, sphericity index of femoral head, Shenton line, Tonnis grade of osteoarthritis, joint congruency, p/a ratio, acetabular anteversion angle, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale scores, and modified Harris hip score (MHHS) were observed. MHHS were divided into three clinically relevant categories: poor (<70 points), good (70-85 points), and excellent (86-91 points). Patient demographic data, as well as preoperative and postoperative radiographic parameters, were subjected to univariate logistic regression analysis. Multiple regression analysis was used to determine factors influencing postoperative MHHS. RESULTS: The follow-up time was 1.0-3.9 years after surgery, with an average of 1.6 years. By the last follow-up, MHHS increased from 70 points before surgery to 91 points after surgery (P < 0.001), WOMAC pain score decreased from 4 points before surgery to 0 points after surgery (P < 0.001). WOMAC functional score decreased (Preoperative: 18.0 [4.0]; Postoperative: 4.0 [0], P = 0.004). Six patients had sensory disturbance of the lateral femoral cutaneous nerve, four of which recovered completely during follow-up. No other complications related to surgical approach, osteotomy, acetabular displacement, acetabular fixation, and postoperative stage were found. There was no significant vascular, nerve, or visceral injuries in any of the patients. On multiple regression analysis, the probability of the postoperative modified Harris hip score of a hip joint with a preoperative lateral center edge angle ≥4.5° being classified as excellent was six times that of angles <4.5° (Exp[ß]: 6.249, 95% CI: 1.03-37.85, P = 0.046). Regression analysis of other factors found no significant correlation with postoperative functional scores. CONCLUSION: Overall functional scores post-PAO significantly improved, and pain symptoms were significantly reduced. Patients with a preoperative lateral center edge angle ≥4.5° had better joint function after surgery.

What Is the Impact of Periacetabular Osteotomy Surgery on Patient Function and Activity Levels?

BACKGROUND: Periacetabular osteotomy (PAO) is a hip preserving procedure performed often in younger, highly active patients. However, counseling patients is difficult, as there are limited data regarding activity level after PAO. The purpose of this study is to analyze the physical activity levels after PAO in a large, prospective multicenter cohort. METHODS: Prospectively collected data from a multicenter study group included 359 hips treated by PAO for hip dysplasia at a mean age of 25.1 years. Patient demographics, radiographic measures, operative data, and clinical outcomes were evaluated preoperatively, at 1 year, and at minimum 2 years postoperatively. Activity level was assessed with the University of California Los Angeles (UCLA) activity score, and patients were stratified into low activity, moderate activity, and high activity groups based on preoperative function. RESULTS: Compared to preoperative scores across the complete cohort, postoperative UCLA scores were improved on average 0.6 points at final follow-up (P = .001). The low activity and moderate activity groups had significant improvement in UCLA scores (P < .001 and P = .0007, respectively), while the high activity groups saw a significant decrease in UCLA activity scores (P < .0001). Modified Harris Hip Score, Hip Disability and Osteoarthritis Score Pain, and Hip Disability and Osteoarthritis Score Sports and Recreation scores were significantly improved across all preoperative activity levels. Multivariable linear regression (r2 = 0.45) confirmed prior ipsilateral surgery as a predictor for change in UCLA score (P = .002). CONCLUSION: Overall, these data suggest that consistent improvements in activity level and function can be expected following PAO surgery, with greater gains experienced by patients with lower preoperative levels of activity.

A Minimally Invasive Technique Using a Modified Stoppa Approach for Periacetabular Osteotomy: A Preliminary Cadaveric Study.

BACKGROUND: Developmental hip dysplasia is diagnosed when the femoral head is not sufficiently covered by the acetabulum. Anterior and lateral cover deficiency is seen, as a result a dysplastic hip joint. Various incision modifications have been developed because of the muscle dissection and wide wound scar in Smith-Peterson incision, which was originally used in Bernese osteotomy. This study evaluates applicability of the modified Stoppa approach in the performance of Bernese periacetabular osteotomy (PAO). MATERIALS AND METHODS: Ten hemipelvises of five donor cadavers were used. The transverse Stoppa incision was made 2 cm over the symphysis pubis for quadrilateral surface exposure and pubic and ischial bone osteotomies. The second skin incision, a few centimeters lateral to the original incision, was made along the tensor fascia lata. Iliac bone osteotomy was performed starting just above the rectus femoris insertion. The displacement of the osteotomy was measured clinically and radiographically. RESULTS: The mean anterior coverage calculated with center-edge angle was improved from 22.8° ±2.8 (range 20° min-28° max) preoperatively to 44.1° ± 3.7 (range 36° min-48° max). The displacement of the osteotomy at the iliopectineal line calculated on the iliac inlet view radiographs was 22.1 ± 3.4 mm (range 15 mm min-26 mm max). The clinical amount of the anterior displacement on the cadavers was 17.8 ± 3.35 mm (range 11 mm-21 mm) and lateral displacement was 20.3 ± 3.23 mm (range 15 mm-24 mm). The amount of the posterior intact bone enlargement at the quadrilateral surface was 5.3 ± 0.48 mm. CONCLUSION: This less traumatic two-incision exposure is an adequate technique for Bernese PAO, allowing the bone to be cut under direct visual observation and reducing the need to use fluoroscopy.

Return to Play After Periacetabular Osteotomy for Treatment of Acetabular Dysplasia in Adolescent and Young Adult Athletes.

BACKGROUND: The Bernese periacetabular osteotomy (PAO) is an effective surgical treatment option for symptomatic acetabular dysplasia. Little evidence exists regarding the results of PAO and rates of return to play (RTP) in an athletic population. HYPOTHESIS: The majority of athletes will demonstrate improvements in functional outcome measures, such as the modified Harris Hip Score and Hip Disability and Osteoarthritis Outcome Score, and will be able to return to sports after PAO. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A comprehensive surgical hip database at an academic referral center was used to identify a subpopulation of athletes on whom PAO was performed. Data analyzed included preceding surgeries, reoperations, and RTP timing and features. Standard pre- and postoperative radiologic parameters and validated functional outcome measures were assessed, and a regression model assessed risk factors for prolonged time to RTP. RESULTS: Of 245 PAOs performed over the 5-year study period, 46 were performed in 41 patients who met inclusion criteria for being an athlete (mean age, 26.2 years; range, 13-41 years; 36 females; 19% of all PAOs), representing a variety of sports. Prior surgery had been performed on 9 hips (20%). Only 1 post-PAO procedure (2%), excision of heterotopic ossification, was performed during the study period. At final follow-up (median, 3.1 years; range, 1.2-4.4 years), significant mean improvements were observed in modified Harris Hip Score (from 71 to 90; P < .001) and Hip Disability and Osteoarthritis Outcome Score (from 64 to 89; P < .001). The University of California-Los Angeles Activity Scale scores were maintained at a high level (range, 8.0-8.2; P = .28). RTP was reported in 80% of patients (37 of 46) at a median of 9 months postoperatively, with increased postoperative pain as the only independent predictor of longer time to RTP. Of these 37 athletes, 27 (73%) returned to the same level, although this was significantly less common (P = .06) in competitive athletes (11 of 19; 58%) than in recreational athletes (16 of 18; 89%). Among those who did return at the same level, 23 of 27 (85%) were able to maintain this level over time, but this was not significantly different between competitive (8 of 11; 73%) and recreational (15 of 16; 94%) athletes (P = .27). CONCLUSION: Most athletic patients undergoing PAO are female patients and show postoperative improvements in function and return to athletic play. However, although there was no decline in overall activity level at a mean of 3 years, self-assessed athletic performance was attained and maintained in approximately one-half of the study population.

Efficiency and Accuracy of Bernese Periacetabular Osteotomy for Adult Hip Dysplasia.

Bernese periacetabular osteotomy (PAO) has several advantages dealing with adolescents and adults acetabular dysplasia. The authors introduced the details and steps performing PAO, with attached video and schematic diagram which demonstrates a perfect PAO in efficiency and accuracy. The patient is an 18-year-old girl, complaining hip pain on the left side for 6 months. Physical examination shows normal gait and range of motion (ROM) of the left hip. Pelvic anteroposterior X-ray shows acetabular dysplasia on the left, and post operation on the right. She is very satisfied with the PAO on the right one year before, so we recommend PAO for the left hip dysplasia again. The key point of PAO includes 4 cuts: ischial cut, pubic cut, acetabular roof cut, and quadrilateral bone cut, and the four cuts should be accomplished accurately. Then the acetabular fragment should be turned to ideal position with the lateral CE angle (LCE) > 25°, the Tönnis acetabular angle 0°, the anterior CE angle (ACE) > 20°, good congruence joint space, and with the hip center medialized slightly. At lastly the acetabular fragment is fixed with proper nails and instruments. The patient is very happy to the surgery with no hip pain, with normal gait, ROM, and Harris hip scores (HHS). In summary, PAO is a relative new and efficient procedure for adult hip dysplasia, requiring accurate techniques. Cadaveric practice and familiar with the local anatomy can help the surgeon overcome the learning curve quickly.

Short to Midterm Results of Bernese Periacetabular Osteotomy for Hip Dysplasia / 대한정형외과학회잡지

PURPOSE: The goal of this study was to analyze the short to midterm results of Bernese periacetabular osteotomy for the patient with hip dysplasia. MATERIALS AND METHODS: Fourteen Bernese periacetabular osteotomies were performed in 13 patients and were followed-up for more than 2.5 years. All patients had been treated at Department of Orthopedic Surgery, Seoul National University Hospital from June 1998 to December 2007. We conducted an interview and asked the patients to complete the Harris hip score and pain visual analogue scale (VAS) score for clinical evaluation. Radiographic measurements included Tonnis osteoarthritis grade, center-edge angle of Wiberg, acetabular angle of Sharp, acetabular depth index, acetabular head index. RESULTS: Mean Harris hip score improved from 63.8 points preoperatively to 82.9 points postoperatively and pain VAS score improved from 7.6 points preoperatively to 0.8 points postoperatively. Based on Tonnis osteoarthritis grade, progression of osteoarthritis was found in 4 hips. Radiologically, center-edge angle of Wiberg, acetabular angle of Sharp, acetabular depth index and acetabular head index improved. Complications included superficial skin infection in one hip and non-union of pubic ramus in one. One patient had metal hypersensitivity to cortical screws and fracture of posterior column. CONCLUSION: The short to midterm results show Bernese periacetabular osteotomy is a satisfactory technique for treating early and mild hip-osteoarthritis patients with hip dysplasia clinically and radiographically.

Bernese Periacetabular Osteotomy for Treatment of Acetabular Dysplasia / 대한정형외과학회잡지

PURPOSE: To evaluate the clinical and radiologic results of Bernese periacetabular osteotomy in treating acetabular dysplasia. MATERIALS AND METHODS: We evaluated the results of 24 Bernese periacetabular osteotomies performed in 21 patients (18 female, 3 male). The osteotomies were performed through an ilioinguinal approach in 20 cases, and dual (anterior and posterior) approaches in 4 cases. The mean age of the patients at the time of surgery was 23.4 years (range, 13.1-36 years). The average follow-up period was 26 months (range, 12-48 months). The Harris hip score was used for clinical evaluation. Radiological changes of acetabular angle, CE angle, acetabular depth, and femoral head coverage were measured. RESULTS: Clinically, the mean Harris hip score improved from 59.3 preoperatively to 88.3 postoperatively. All four radiological measurements improved significantly after surgery (Wilcoxon Rank Sum test, p<0.05). The following complications were noted: superficial skin infection (1 case), posterior column fracture (3 cases), temporary sciatic nerve symptoms (2 cases), and conversion to total hip arthroplasty (2 cases). CONCLUSION: Bernese periacetabular osteotomy is an effective surgical treatment for acetabular dysplasia in adults.

Bernese Periacetabular Osteotomy Using Dual Approaches for Hip Dysplasias / 대한정형외과학회잡지

PURPOSE: This study was aimed to evaluate the usefulness of the dual approaches used in Bernese periacetabular osteotomy for hip dysplasias, and also to comparatively evaluate the single anterior approach. MATERIALS AND METHODS: We performed a clinical and radiographic assessment of 15 cases (5 cases by the anterior approach and 10 cases by the dual approaches) of periacetabular osteotomy which had been followed up for more than 1 year. RESULTS: All patients had an improved Harris hip score, CE angle, acetabular angle, acetabular depth, femoral head coverage and medial shift of the femoral head. Gait improvement was confirmed by gait analysis. The mount of correction of the CE angle was more by the anterior approach than by the dual approaches, which was due to overcorrection. There were no statistical differences in the operation times or in the amounts of bleeding of the two approaches. Posterior column fractures occurred in 4 hips, which were due to blind osteotomies by the single approach, but none occurred after the dual approaches. CONCLUSION: We visualized all osteotomy sites and could perform the osteotomies easily and were able to decrease the number of complications associated with the dual approaches.