Periacetabular Osteotomy Research Articles

CORR Insights®: Does Periacetabular Osteotomy Change Sagittal Spinopelvic Alignment?

CORR Insights®: Does Periacetabular Osteotomy Change Sagittal Spinopelvic Alignment?

Dysplastic Hips That Are Too Late for Periacetabular Osteotomy Are Not Too Early for Total Hip Arthroplasty

BackgroundTotal hip arthroplasty (THA) is often performed in symptomatic patients who have hip dysplasia and do not qualify for periacetabular osteotomy. The impact of osteoarthritis (OA) severity on postoperative outcomes in dysplasia patients who undergo THA is not well described. We hypothesized that dysplasia patients who have mild OA have slower initial recovery postoperatively but similar one-year patient-reported outcome measures (PROMs) compared to dysplasia patients who have severe OA. MethodsWe performed a retrospective review at a single academic institution over a 6-year period of patients who have dysplasia who underwent THA compared to patients who have primary OA who underwent THA. There were 263 patients who had dysplasia, compared to 1,225 THA patients who did not have dysplasia. Within the dysplasia cohort, we compared PROMs stratified by dysplasia and OA severity. The diagnosis of dysplasia was verified using the radiographic lateral center edge angle. A minimum one-year follow-up was required. The PROMs were collected through one year postoperatively. Logistic and linear regression models were used, adjusting for age, sex, body mass index, and Charlson comorbidity index. ResultsNo significant differences were found in postoperative PROMs or revision rates (P = .58). When stratified by dysplasia severity, patients who had lower lateral center edge angle had more improvement in physical function scores from preoperative to 2 weeks (P < .01) and higher physical function scores at 2 weeks (P = .03). When stratified by OA severity, patients who had a worse Tönnis score had more improvement in physical function scores from preoperative to 2 weeks (P < .01). Recovery curves in dysplasia patients based on dysplasia and OA severity were not significantly different at 6 weeks, 1 year, and 2 years postoperative. ConclusionsPatients who had hip dysplasia and mild OA had similar recovery curves compared to those who had severe OA or who did not have dysplasia. We believe that THA is a reasonable surgical intervention for symptomatic dysplasia patients who have mild arthritis and do not qualify for periacetabular osteotomy.

Use of the flat panel detector fluoroscope reduces radiation exposure during periacetabular osteotomy

The Periacetabular Osteotomy is a technically demanding procedure that requires precise intraoperative evaluation of pelvic anatomy. Fluoroscopic images pose a radiation risk to operating room staff, scrubbed personnel, and the patient. Most commonly, a Standard Fluoroscope with an Image Intensifier is used. Our institution recently implemented the novel Fluoroscope with a Flat Panel Detector. The purpose of this study was to compare radiation dosage and accuracy between the two fluoroscopes. A retrospective review of a consecutive series of patients who underwent Periacetabular Osteotomy for symptomatic hip dysplasia was completed. The total radiation exposure dose (mGy) was recorded and compared for each case from the standard fluoroscope (n = 27) and the flat panel detector (n = 26) cohorts. Lateral center edge angle was measured and compared intraoperatively and at the six-week postoperative visit. A total of 53 patients (96% female) with a mean age and BMI of 17.84 (± 6.84) years and 22.66 (± 4.49) kg/m2 (standard fluoroscope) and 18.23 (± 4.21) years and 21.99 (± 4.00) kg/m2 (flat panel detector) were included. The standard fluoroscope averaged total radiation exposure to be 410.61(± 193.02) mGy, while the flat panel detector averaged 91.12 (± 49.64) mGy (p < 0.0001). The average difference (bias) between intraoperative and 6-week postoperative lateral center edge angle measurement was 0.36° (limits of agreement: − 3.19 to 2.47°) for the standard fluoroscope and 0.27° (limits of agreement: − 2.05 to 2.59°) for the flat panel detector cohort. Use of fluoroscopy with flat panel detector technology decreased the total radiation dose exposure intraoperatively and produced an equivalent assessment of intraoperative lateral center edge angle. Decreasing radiation exposure to young patients is imperative to reduce the risk of future comorbidities.

Does psychological distress predict risk of orthopaedic surgery and postoperative opioid prescribing in patients with hip pain? A retrospective study

BackgroundClinicians and public health professionals have allocated resources to curb opioid over-prescription and address psychological needs among patients with musculoskeletal pain. However, associations between psychological distress, risk of surgery, and opioid prescribing among those with hip pathologies remain unclear.MethodsUsing a retrospective cohort study design, we identified patients that were evaluated for hip pain from January 13, 2020 to October 27, 2021. Patients’ surgical histories and postoperative opioid prescriptions were extracted via chart review. Risk of hip surgery within one year of evaluation was analyzed using multivariable logistic regression. Multivariable linear regression was employed to predict average morphine milligram equivalents (MME) per day of opioid prescriptions within the first 30 days after surgery. Candidate predictors included age, gender, race, ethnicity, employment, insurance type, hip function and quality of life on the International Hip Outcome Tool (iHOT-12), and psychological distress phenotype using the OSPRO Yellow Flag (OSPRO-YF) Assessment Tool.ResultsOf the 672 patients, n = 350 (52.1%) underwent orthopaedic surgery for hip pain. In multivariable analysis, younger patients, those with TRICARE/other government insurance, and those with a high psychological distress phenotype had higher odds of surgery. After adding iHOT-12 scores, younger patients and lower iHOT-12 scores were associated with higher odds of surgery, while Black/African American patients had lower odds of surgery. In multivariable analysis of average MME, patients with periacetabular osteotomy (PAO) received opioid prescriptions with significantly higher average MME than those with other procedures, and surgery type was the only significant predictor. Post-hoc analysis excluding PAO found higher average MME for patients undergoing hip arthroscopy (compared to arthroplasty or other non-PAO procedures) and significantly lower average MME for patients with public insurance (Medicare/Medicaid) compared to those with private insurance. Among those only undergoing arthroscopy, older age and having public insurance were associated with opioid prescriptions with lower average MME. Neither iHOT-12 scores nor OSPRO-YF phenotype assignment were significant predictors of postoperative mean MME.ConclusionsPsychological distress characteristics are modifiable targets for rehabilitation programs, but their use as prognostic factors for risk of orthopaedic surgery and opioid prescribing in patients with hip pain appears limited when considered alongside other commonly collected clinical information such as age, insurance, type of surgery pursued, and iHOT-12 scores.

3D pre-operative planning and patient-specific guides for re-directional peri-acetabular osteotomy in children and adolescents

Surgical procedures to correct hip dysplasia associated with subluxation or dislocation of the femoral head are complex. The 3D geometric abnormalities of the acetabulum and proximal femur vary across patients. We, therefore, suggest a patient-specific surgical treatment involving computer-assisted 3D planning of the peri-acetabular osteotomies, taking into account the femoral head position; 3D printing of patient-specific guides for the cuts, repositioning, and fixation; and intra-operative application of the simulated displacements with their fixation. Level of evidenceIV.

Combined hip arthroscopy with periacetabular osteotomy for hip dysplasia: a systematic review

Combined hip arthroscopy with periacetabular osteotomy for hip dysplasia: a systematic review

Clinical outcomes after hip arthroscopy in acetabular dysplastic patients, previously treated with periacetabular osteotomy: a minimum of two-year follow-up data from the Danish Hip Arthroscopy Registry

ABSTRACT Periacetabular osteotomy (PAO) is the treatment of choice in dysplastic acetabulum. Due to continued symptoms, 2–11% of these patients require an additional hip arthroscopy. The purpose of this study was to report clinical outcome after a minimum of 2-year follow-up of additional hip arthroscopy after PAO with data from Danish Hip Arthroscopy Registry. Inclusion criteria in the study cohort were PAO surgery resulting in an additional hip arthroscopy procedure. The cohort was evaluated according to the surgical findings and patient-related outcome measures (PROMs) pre-operatively and at 2-year follow-up. A total of 287 patients were included in the study cohort. PROMs improved significantly in all subscales from pre-operatively to 2-year follow-up in the study cohort. According to PROM subscales, 47.8–57.6% and 25.2–38.2% achieved Minimal Clinical Important Difference and Patient Acceptable Symptom State, respectively. This study demonstrates, in PAO-treated patients, significant PROM improvements after additional hip arthroscopy. Unfortunately, only ∼50% and 30% achieved Minimal Clinical Important Difference and Patient Acceptable Symptom State, respectively.

Does Periacetabular Osteotomy Change Sagittal Spinopelvic Alignment?

There are few data on the impact of periacetabular osteotomy (PAO) on sagittal spinopelvic alignment. Prior studies have attempted to delineate the relationship by performing measurements on AP radiographs and using mathematical models to determine changes in postoperative pelvic tilt. This information is clinically significant to a surgeon when evaluating acetabular/pelvic position intraoperatively and understanding spinopelvic alignment changes postoperatively; therefore, radiographic changes from PAO should be described in more detail. In this study, we asked: (1) Does the performance of PAO result in consistent changes in spinopelvic alignment, as measured on EOS radiographs? (2) Does this differ for unilateral versus bilateral PAOs? (3) Does this differ in the setting of a mobile spine versus an immobile spine? (4) Does this differ based on preoperative pelvic tilt? Mean preoperative and at least 1-year postoperative (15 ± 8 months from surgery, minimum 11 months, maximum 65 months) EOS hip-to-ankle standing and sitting radiographs for 55 patients in a prospectively collected registry who underwent PAO with a single surgeon from January 1, 2019, to January 11, 2022, were measured for pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, lateral center-edge angle, L1 pelvic angle, and pubic symphysis to the sacroiliac index. Normality was assessed and paired sample t-tests (normally distributed data) or Wilcoxon signed rank tests (not normally distributed data) were utilized to assess if any measurements changed from preoperative to postoperative. Patients were then divided based on whether they had unilateral or bilateral dysplasia and unilateral or bilateral surgery, and these subgroups were analyzed the same way as the entire cohort. Two more subgroups were then formed based on lumbar mobility, defined as a change in sitting-to-standing lumbar lordosis less or greater than 1 SD from the population mean preoperatively, and the subgroups were analyzed the same way as the entire cohort. Finally, two additional subgroups were formed, preoperative standing pelvic tilt less than 10° and more than 20°, and analyzed the same as the entire cohort. For the entire cohort, the median (IQR) standing lateral-center edge angle increased 17°, from a median of 21° (10°) to a median of 38° (8° [95% confidence interval (CI) 16° to 20°; p < 0.001). The median sitting lateral center-edge angle increased 17°, from a median of 18° (8°) to a median of 35° (8° [95% CI 14° to 19°]; p < 0.001). Standing pelvic incidence increased from 50° ± 11° to 52° ± 12° (mean difference 2° [95% CI 1° to 3°]; p = 0.004), but there were no changes for other measured parameters. There were no changes in any of the spinopelvic parameters for patients with unilateral dysplasia receiving a unilateral PAO, but patients with bilateral dysplasia who underwent bilateral PAOs demonstrated an increase in pelvic incidence from 57° (14°) to 60° (16°) (95% CI 1° to 5°; p = 0.02) and a decrease in pubic symphysis to sacroiliac index from 84 mm (24 mm) to 77 mm (23 mm) (95% CI -7° to -2°; p = 0.007). Patients with mobile lumbar spines preoperatively did not exhibit any changes in sagittal spinopelvic alignment, but patients with immobile lumbar spines preoperatively experienced several changes after surgery. Patients with less than 10° of standing pelvic tilt demonstrated a median (IQR) 2° increase in pelvic incidence from median 43° (9°) to 45° (12° [95% CI 0.3° to 4°]; p = 0.03), but they did not experience any other changes in sagittal spinopelvic alignment parameters postoperatively. Patients with preoperative pelvic tilt more than 20° did not experience any change in sagittal spinopelvic parameters. PAO increases pelvic incidence, potentially because of anterior translation of the hip center. There were no changes in other spinopelvic parameters postoperatively except after bilateral PAO. Additionally, patients lacking spine mobility preoperatively, indicated by a minimal change in lumbar lordosis between standing and sitting positions, may experience several changes in spinopelvic alignment, including increased mobility of their spine after PAO. This may be because of decreased compensatory spine splinting after increasing acetabular coverage, but further research including patient-reported outcomes is warranted. Level III, therapeutic study.

Unveiling the learning curve of periacetabular osteotomy.

Periacetabular osteotomy (PAO) is widely recognized as a demanding surgical procedure for acetabular reorientation. Reports about the learning curve have primarily focused on complication rates during the initial learning phase. Therefore, our aim was to assess the PAO learning curve from an analytical perspective by determining the number of PAOs required for the duration of surgery to plateau and the accuracy to improve. The study included 118 consecutive PAOs in 106 patients. Of these, 28 were male (23.7%) and 90 were female (76.3%). The primary endpoint was surgical time. Secondary outcome measures included radiological parameters. Cumulative summation analysis was used to determine changes in surgical duration. A multivariate linear regression model was used to identify independent factors influencing surgical time. The learning curve in this series was 26 PAOs in a period of six months. After 26 PAO procedures, a significant drop in surgical time was observed and a plateau was also achieved. The mean duration of surgery during the learning curve was 103.8 minutes (SD 33.2), and 69.7 minutes (SD 18.6) thereafter (p < 0.001). Radiological correction of acetabular retroversion showed a significant improvement after having performed a total of 93 PAOs, including anteverting PAOs on 35 hips with a retroverted acetabular morphology (p = 0.005). Several factors were identified as independent variables influencing duration of surgery, including patient weight (β = 0.5 (95% confidence interval (CI) 0.2 to 0.7); p < 0.001), learning curve procedure phase of 26 procedures (β = 34.0 (95% CI 24.3 to 43.8); p < 0.001), and the degree of lateral correction expressed as the change in the lateral centre-edge angle (β = 0.7 (95% CI 0.001 to 1.3); p = 0.048). The learning curve for PAO surgery requires extensive surgical training at a high-volume centre, with a minimum of 50 PAOs per surgeon per year. This study defined a cut-off value of 26 PAO procedures, after which a significant drop in surgical duration occurred. Furthermore, it was observed that a retroverted morphology of the acetabulum required a greater number of procedures to acquire proficiency in consistently eliminating the crossover sign. These findings are relevant for fellows and fellowship programme directors in establishing the extent of training required to impart competence in PAO.

The Windshield Wiper Sign Is an Instability-Related Osteochondral Defect of the Anterolateral Femoral Head

PurposeTo investigate a radiographic sign believed to be indicative of hip instability and acetabular suction seal disruption in the native hip, coined the “windshield wiper” (WSW) sign. Materials and MethodsA retrospective review was performed for patients who underwent periacetabular osteotomy (PAO) with the senior author between March 2021 and September 2023. A WSW sign was identified on plain films as a concave or flat osteochondral defect on the anterolateral femoral head extending medial to the head-neck junction with resultant loss of femoral head sphericity in the native hip. Every patient underwent a standardized series of radiographs, as well as computed tomography and magnetic resonance imaging. All patients underwent arthroscopy prior to PAO to address intra-articular pathology and other indicated procedures. The osteochondral defect and resultant suction seal disruption were verified during arthroscopy. These patients were then compared with a control group of arthroscopically treated hips without hip instability. ResultsOf 250 patients reviewed, a total of 19 hips in 17 patients (prevalence of 7.6%) demonstrated radiographic evidence of the WSW sign. All patients with a WSW sign presented with symptomatic clinical hip instability requiring a PAO. The mean patient age was 31.2 years, with a mean lateral center edge angle (LCEA) of 14.3 degrees. There were 13 hips (68.4%) with dysplasia, 4 (21.1%) with borderline dysplasia, and 2 (10.5%) with a normal LCEA. All patients with a WSW sign and LCEA ≥20° displayed significant femoral antetorsion abnormalities. All arthroscopic videos and images demonstrated a compromised suction seal. Of the 50 control group hips reviewed, the WSW sign was not identified. ConclusionsThe WSW sign is an uncommon radiographic finding in patients with hip instability. When identified, it can be predictive of substantial instability, especially in cases which are otherwise considered borderline dysplasia or normal based on LCEA. Level of EvidenceIII, case-control study

The Everted Acetabular Labrum: Outcomes of Surgical Management

Background: An everted acetabular labrum (EL) is a pathologic variant in which the labrum is flipped to the capsular side of the acetabular rim. An iatrogenic EL is a known complication of a poorly executed labral repair, and a recent study described the native acetabular EL. Purpose: To analyze surgical outcomes after advancement or reconstruction of an EL in a native hip. Study Design: Cohort study; Level of evidence, 3. Methods: This was a multicenter retrospective review of prospectively collected data on primary hip arthroscopic surgeries performed between 2013 and 2023. An EL was identified arthroscopically as a labrum–femoral head gap while off traction in the native hip. All patients with EL who were analyzed in this study underwent arthroscopic labral repair and advancement or labral augmentation or reconstruction. Patients with hip dysplasia also underwent periacetabular osteotomy with or without a derotational femoral osteotomy. Patient-reported outcomes (PROs) were assessed using the 12-item International Hip Outcome Tool (iHOT-12) and the Nonarthritic Hip Score. PROs were obtained preoperatively and up to 24 months after surgery. PROs were compared with those of a case-matched control cohort in a 1:2 ratio. Only patients with PROs available at ≥1 year postoperatively were included in the outcome analysis. Results: A total of 111 patients (129 hips) with EL during the study period were identified, with PROs available in 96 hips. The mean age of patients with EL was 30.5 years, and women made up 87% of the cohort. Of the 129 hips with an EL, an isolated diagnosis of an EL was present in 11.6% of hips. Deficient acetabular coverage (lateral center-edge angle <25°) was seen in 40.6% of EL hips. No difference was seen in iHOT-12 scores between EL and control groups at 12- or 24-month follow-up (P = .18 and .94, respectively). Patients with EL reported a significant improvement of PROs at latest follow-up (P < .001 for iHOT-12 and Nonarthritic Hip Score). Conclusion: Surgical management of a native EL with restoration of the labral seal on the femoral head and correction of concomitant pathologies resulted in significant clinical improvement, with postoperative outcome scores comparable to those of patients without an EL. These findings provide evidence supporting surgical intervention for a native EL.

The Use of Combined Hip Arthroscopy and Periacetabular Osteotomy for Hip Dysplasia Is Increasing and Has Low Complication Rates

PurposeTo analyze annual use of hip arthroscopy (HA) and Bernese periacetabular osteotomy (PAO) for the treatment of hip dysplasia (HD), as well as post-operative outcomes, including ipsilateral reoperations. MethodsNinth and Tenth Revision codes of the International Classification of Diseases were used to query the PearlDiver™ Mariner database from January 2010 through January 2022 to identify patients aged 10-59 years who had a presenting diagnosis of HD and subsequently underwent: 1) HA; 2) PAO; or 3) combined HA and PAO (HA-PAO, defined as PAO on the same day or within 28 days following HA). We analyzed annual rates for each treatment, as well as rates of post-operative emergency visits, readmissions and five-year ipsilateral secondary operations (determined via Kaplan-Meier analysis). ResultsThere were 32,068 patients who underwent surgical treatment of HD. For HA, PAO, and HA-PAO, there were 29,700, 2,083, and 285 patients, respectively. All operations had the highest percent-increase from 2015 to 2016. HA and HA-PAO peaked in 2021, while PAO peaked in 2019. For HA, PAO, and HA-PAO, the majority of cases were performed in female patients and patients aged 30-49 years, 10-19 years, and 10-29 years, respectively. The five-year incidence of ipsilateral secondary operations, which include revision HA, PAO, or conversion to total hip arthroplasty, was 9.2% (95% CI: 8.6%- 9.8%) in the HA group and 6.5% (95% CI: 4.1%- 8.8%) in the PAO group. Combining HA with PAO resulted in so few secondary operations that Kaplan-Meier analysis was infeasible. The PAO cohort had the highest 30-day emergency visit and 90-day readmission rates, with infection as the most common cause for readmission. ConclusionHA is more frequently performed than PAO for hip dysplasia. HA-PAO is rising at the greatest rate, demonstrating fewer complications and reoperations.

Early And Mid-Term Radiological Results of Isolated Pembersal Procedure in Cases of Developmental Dislocation of The Hip

Aim: Early diagnosis and timely care is important in patients with Developmental Hip Dysplasia (DDH). Late presenting or neglected patients may require various osteotomy procedures. There is a limited number of articles in the literature on Pembersal osteotomy in DDH surgery. The aim of this study was to assess the outcomes of isolated Pembersal osteotomy in children over 18 months of age with DDH. Materials and Methods: A retrospective analysis was made of the outcomes of patients who underwent Pembersal osteotomy for DDH at our clinic from 2014 to 2021. The study included 9 children (7 girls, 2 boys) aged between 19 and 36 months with at least 2 years of follow-up who underwent isolated periacetabular Pembersal osteotomy with open reduction. Preoperative, early postoperative, 6 weeks postoperative and final follow-up radiographs were evaluated and Wiberg's centre-edge angle (CEA), the acetabular index (AI) and Tönnis grades were noted. Results: The mean age of the patients was 28.75 months and the follow-up period was 50.33 months. CEA and AI showed improvement in the early postoperative period and this improvement continued in the later periods. Tönnis staging showed postoperative improvement in all patients, and this improvement continued in the early postoperative period and on the 6-week follow-up radiographs. At the final follow-up examination, 3 hips had CEA &lt;20º, AI &gt;20º and Tönnis stage ≥2 and these 3 hips were considered as a radiologically poor outcome. Conclusion: This study demonstrated that isolated Pembersal osteotomy is an effective and safe option for the treatment of developmental dysplasia of the hip, with improvement in acetabular index and other radiological parameters. Keywords: Developmental dysplasia of the hip, periacetabular osteotomy, Pembersal osteotomy, centre-edge angle, acetabular index

Comparison of Two Surgical Approaches for Periacetabular Osteotomy: A Retrospective Study of Patients with Developmental Dysplasia of the Hip.

Given the intricate challenges and potential complications associated with periacetabular osteotomy (PAO) for developmental dysplasia of the hip (DDH). Our study aimed to compare the clinical and imaging benefits and drawbacks of two surgical approaches, the modified Stoppa combined iliac spine approach and the modified Smith-Peterson approach, for treating PAO and to provide guidance for selecting clinical approaches. A retrospective analysis of 56 patients with 62 DDHs was conducted from June 2018 to January 2022. The experimental group underwent surgery via the modified Stoppa combined iliac spine approach, while the control group underwent surgery via the modified Smith-Peterson approach for periacetabular osteotomy and internal fixation. Basic statistical parameters, including age, sex, BMI, and preoperative imaging data, were analyzed. Differences in surgical time, intraoperative blood loss, and postoperative imaging data were compared, as were differences in preoperative and postoperative imaging data between the two groups. There were 28 hips in the experimental group and 34 in the control group. Moreover, there was no significant difference in the basic parameters between the experimental and control groups. Before and after the operation, for the LCE angle, ACE angle, and Tonnis angle, there was no significant difference in acetabular coverage (p > 0.05). However, there were significant differences between the two groups in terms of the above four indicators before and after the operation (p < 0.05). After the operation, the experimental group exhibited significant increases in both lateral and anterior acetabular coverage of the femoral head. However, the experimental group had longer operation times and greater bleeding volumes than did the control group. Despite this, the experimental group demonstrated significant advantages in protecting the lateral femoral cutaneous nerve compared to the control group. The modified Stoppa combined iliac spine approach can be considered a practical approach for PAO and is more suitable for patients with DDH who plan to be treated by one operation than the classic modified Smith-Peterson approach for PAO.

Long-term results of a modified Spitzy shelf operation for hip dysplasia: 79 adults with a mean follow-up of 33 years.

There is no consensus regarding the treatment of symptomatic hip dysplasia in adolescents and adults. Most previous studies have insufficient follow-up time. The aim of this study was to assess the long-term outcome of a modified Spitzy shelf procedure. We reviewed 79 adults with 94 acetabular shelf operations between 1976 and 2000. Mean age at surgery was 33.7years (range 13-54). Indication for surgery was acetabular dysplasia with or without hip pain. Outcome was evaluated using hip pain pre- and postoperatively and Kaplan-Meier survival analysis with conversion to total hip replacement (THR) as the endpoint. Hip pain was reported in 84% of the hips preoperatively and in 21% one year postoperatively. 63 hips (65%) had undergone THR at a mean patient age of 54.3years (range 29-76). The mean survival time from Spitzy operation to THR was 17.2years (range 1-39). Survival was 86% at 10-year follow-up, 56% at 20-year follow-up, and 36% at 30-year follow-up. Predictors of THR were age at surgery ≥ 30years and preoperative osteoarthritis (OA). The rate of complications was 12%, but most were mild to moderate. The modified Spitzy shelf operation had a good effect on hip pain. The long-term survival with conversion to THR as the endpoint in hips without preoperative OA was similar to that reported after periacetabular osteotomy. This indicates that the shelf procedure may be a suitable option in adolescents and young adults with milder degrees of hip dysplasia without OA.

Maintenance of acetabular correction following PAO: a multicenter study comparing stainless-steel and titanium screws.

Stainless-steel screws are commonly used for fragment fixation during periacetabular osteotomy (PAO) at our institutions. Titanium is reserved for patients with documented nickel allergies. Titanium screws possess a significantly lower Young's modulus than stainless steel and, therefore, potentially less resistance to physiologic loading. Thus, we hypothesized that the use of titanium screws might be associated with changes in acetabular correction prior to healing. The aim of this study was to compare the maintenance of acetabular correction following PAO using stainless-steel or titanium screws. A documented nickel allergy was confirmed with an allergy specialist. Patients' age at surgery, gender and BMI were collected. The lateral center-edge angle of Wiberg (LCEA), medial center-edge angle (MCEA), anterior wall index (AWI), posterior wall index (PWI) and Tönnis angle were measured. The delta value for radiographic parameters was calculated as the difference between values immediately post-operation and at 6 months post-operation. Only age at surgery (P < 0.001) and the pre-operative LCEA (P = 0.013) were significantly different between groups (Tables I and II). The remaining pre- and post-operative radiological measurements were similar (Table II). Comparison of delta values at 6 months follow-up indicated no significant differences between screw types (Table III). No patients in the titanium group had a trans-iliac retrograde screw included in their construct (P = 0.003). All patients healed from their osteotomies. The use of titanium screws in patients with an allergy to nickel was not associated with differences in acetabular correction or the rate of osseous union rates despite its lower inherent mechanical properties.

Functional and radiological outcomes of periacetabular osteotomy for hip dysplasia in patients under fifty years using a minimally invasive approach—a single surgeon series with a minimum follow up of two years

PurposeWe conducted a retrospective analysis of prospectively collected data to evaluate (1) the extent of surgical correction following minimally invasive periacetabular osteotomy, (2) improvements in functional outcomes and any potential predictors for favourable outcome, and (3) complications after minimally invasive periacetabular osteotomy.MethodsA total of 352 minimally invasive periacetabular osteotomy procedures were performed on 312 hip dysplasia patients between 2013 and 2020. Radiological parameters such as lateral centre edge angle, acetabular index, and Tönnis grade of arthritis were calculated. Patients also completed a range of patient reported outcome measures. Wilcoxon signed-rank tests were performed to assess for differences between patient reported outcome measures and radiological outcomes across the follow-up periods. Univariate linear regression and logistic regression were used to assess for predictors of change in functional outcome.ResultsPatients had a significant correction in mean lateral centre edge angle from 17.2° to 35.3° (p < 0.001) and mean acetabular index from 13.2° to − 0.82°. At one year follow-up all patient reported outcome measures were significantly greater than their baseline measurements and this improvement was maintained at two years. Changes in patient reported outcome measures were independent of radiological parameters such as change in the lateral centre edge angle and acetabular index, pre-operative Tönnis grade, and patient factors such as age and sex. A total of 5.11% of patients developed post-operative complications, with four requiring posterior column fixation. Four patients (1.12%) needed a total hip replacement.ConclusionMinimally invasive periacetabular osteotomy is a safe procedure that provides significant functional outcome improvements following surgery at six months which is maintained at two years. More than three-fourths of patients achieved improvement of iHOT-12 score beyond the minimal clinically important difference and more than half of the patients achieved substantial clinical benefit for iHOT-12 score.

Periacetabular osteotomy: an analysis of social media to determine the most common questions asked by the periacetabular osteotomy population

BackgroundThe Bernese Periacetabular Osteotomy (PAO) has become a popular surgery for fixing development dysplasia of the hip, yet the most common concerns of the PAO population remains ambiguous. The aim of this study was to investigate Facebook, Instagram and Twitter to further understand what the most common preoperative and postoperative questions patients undergoing PAO are asking. We hypothesized most questions would be asked by patients in the preoperative timeframe with regards to education surrounding PAO surgery.MethodsFacebook, Instagram and Twitter were queried consecutively from February 1, 2023 to November 23, 2011. Facebook was searched for the two most populated interest groups; “Periacetabular Osteotomy (PAO)” and “Periacetabular Osteotomy Australia”. Instagram and Twitter were queried for the most popular hashtags: “#PAOwarrior”, “#PAOsurgery”, “#periacetabularosteotomy”, “#periacetabularosteotomyrecovery”, and “#paorecovery”. Patient questions were categorized according to preoperative and postoperative questions. Questions were further placed into specific themes in their respective preoperative or postoperative question types.ResultsTwo thousand five hundred and fifty-nine posts were collected, with 849 (33%) posts containing 966 questions. Of the 966 questions, 443 (45.9%) and 523 (54.1%) were preoperative and postoperative questions, respectively. The majority of questions were postoperative complication related (23%) and symptom management (21%). Other postoperative questions included recovery/rehabilitation (21%), and general postoperative questions (18%). The most common preoperative questions were related to PAO education (23%). Rehabilitation (19%), hip dysplasia education (17%), and surgeon selection (12%) were other preoperative questions topics included. Most questions came from Facebook posts. Of 1,054 Facebook posts, 76% were either preoperative or postoperative questions and from the perspective of the patient (87%).ConclusionThe majority of patients in the PAO population sought advice on postoperative complications and symptom management. Some patients asked about education surrounding PAO surgery. Understanding the most common concerns and questions patients have can help providers educate patients and focus on more patient-relevant perioperative conversations.

Primary Hip Arthroscopy in Patients With Acetabular Dysplasia: A Systematic Review of Published Clinical Outcomes at Minimum 5-Year Follow-up

Background: Hip arthroscopy in patients with borderline hip dysplasia has satisfactory outcomes at short-term follow-up; however, the data on midterm outcomes are inconsistent, and failure rates are high in some studies, limiting understanding of the role and utility of hip arthroscopy in this patient cohort. Purpose: To provide an up-to-date, evidence-based review of the clinical outcomes of primary hip arthroscopy in patients with frank or borderline hip dysplasia at ≥5-year follow-up and report the failure rate and progression to total hip arthroplasty in this cohort. Study Design: Systematic review; Level of evidence, 4. Methods: A comprehensive literature search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were included if they evaluated outcomes of primary hip arthroscopy in patients with lateral center-edge angle (LCEA) <25° at ≥5-year follow-up. Risk of bias assessment was performed using the methodological index for non-randomized studies scoring system. Level of evidence was determined using criteria from the Oxford Centre for Evidence-Based Medicine. Results: Nine studies were included in this review. Patients with LCEA <25° demonstrated satisfactory clinical outcomes, high patient satisfaction, and significant postoperative improvements in patient-reported outcomes (PROs) at follow-up ranging from a ≥5 to 10 years. Studies comparing patients with dysplasia to those without did not demonstrate significant differences in preoperative, postoperative, or delta PROs or in failure, reoperation, or revision rates. There was no overall significant correlation between outcomes and LCEA stratification. Conclusion: Hip arthroscopy in carefully selected patients with LCEA <25° can be successful at mid- to long-term follow-up and may provide clinical outcomes and failure rates comparable with patients with normal LCEA, understanding that this is a singular, 2-dimensional radiographic measure that does not differentiate instability from impingement or combinations thereof, warranting future studies delineating these differences. These findings suggest that hip dysplasia may not be an absolute contraindication for isolated hip arthroscopy and may serve as a viable intervention with consideration of staged future periacetabular osteotomy (PAO). Importantly, this review does not suggest that hip arthroscopy alters the natural history of dysplasia; therefore, patients with dysplasia should be counseled on the potential utility of PAO by appropriate hip preservation specialists.

Acetabular retroversion: functional or anatomical?

The aim of this study is to evaluate whether acetabular retroversion (AR) represents a structural anatomical abnormality of the pelvis or is a functional phenomenon of pelvic positioning in the sagittal plane, and to what extent the changes that result from patient-specific functional position affect the extent of AR. A comparative radiological study of 19 patients (38 hips) with AR were compared with a control group of 30 asymptomatic patients (60 hips). CT scans were corrected for rotation in the axial and coronal planes, and the sagittal plane was then aligned to the anterior pelvic plane. External rotation of the hemipelvis was assessed using the superior iliac wing and inferior iliac wing angles as well as quadrilateral plate angles, and correlated with cranial and central acetabular version. Sagittal anatomical parameters were also measured and correlated to version measurements. In 12 AR patients (24 hips), the axial measurements were repeated after matching sagittal pelvic rotation with standing and supine anteroposterior radiographs. Acetabular version was significantly lower and measurements of external rotation of the hemipelvis were significantly increased in the AR group compared to the control group. The AR group also had increased evidence of anterior projection of the iliac wing in the sagittal plane. The acetabular orientation angles were more retroverted in the supine compared to standing position, and the change in acetabular version correlated with the change in sagittal pelvic tilt. An anterior pelvic tilt of 1° correlated with 1.02° of increased cranial retroversion and 0.76° of increased central retroversion. This study has demonstrated that patients with symptomatic AR have both an externally rotated hemipelvis and increased anterior projection of the iliac wing compared to a control group of asymptomatic patients. Functional sagittal pelvic positioning was also found to affect AR in symptomatic patients: the acetabulum was more retroverted in the supine position compared to standing position. Changes in acetabular version correlate with the change in sagittal pelvic tilt. These findings should be taken into account by surgeons when planning acetabular correction for AR with periacetabular osteotomy.