Anteverting Periacetabular Osteotomy Research Articles

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.

Treatment of Hip Instability in Children With Down Syndrome: Keys to Managing a Challenging Problem.

Management of hip instability in children with Down syndrome is a challenging task to undertake for even the most experienced surgeons. As life expectancy of these patients increases, the importance of preserving functional mobility and hip joint stability in order to minimize late hip degeneration and pain has become a priority. The aim of this study is to evaluate the clinical and radiographic outcomes of children with Down syndrome and hip instability who underwent surgical reconstruction with femoral and/or acetabular procedures. We performed a retrospective review of all children with Down syndrome age 18 years and younger, who underwent surgical intervention to address hip instability between 2003 and 2017. Data was recorded detailing the patient's demographics, preoperative and postoperative functional status and surgical details. Preoperative and postoperative radiographic analysis was performed as well as 3-dimensional computed tomography scan evaluation, when available. All major and minor complications were recorded and classified using the Severin radiographic classification and the Clavien-Dindo-Sink clinical classification. We studied 28 hips in 19 children that were followed for an average of 4.4 years postsurgical intervention for hip instability. The majority of patients improved in all radiographic parameters. A total of 14 hips (50%) had complications and 9 hips (32%) required a secondary surgery. Of those complications, 2 hips (7%) developed avascular necrosis and 4 hips (14%) developed recurrent instability after the index procedure. Two of these hips had a subsequent anteverting periacetabular osteotomy that produced a stable hip at final follow up. Surgical management of hip instability in children with Down syndrome remains challenging. The treating surgeon must have a thorough understanding of the pathoanatomy and design the surgical treatment to meet all of the underlying sources of instability. Combined femoral and acetabular osteotomies plus capsulorrhaphy are often required along with postoperative hip spica immobilization. Although complication and revision surgery rates are high, hip stability and good functional outcomes can be achieved.

What Are the Early Outcomes of True Reverse Periacetabular Osteotomy for Symptomatic Hip Overcoverage?

What Are the Early Outcomes of True Reverse Periacetabular Osteotomy for Symptomatic Hip Overcoverage?

Hips With Acetabular Retroversion Can Be Safely Treated With Advanced Arthroscopic Techniques Without Anteverting Periacetabular Osteotomy: Midterm Outcomes With Propensity-Matched Control Group

Background: Different options, from reverse (anteverting) periacetabular osteotomy to hip arthroscopy, have been proposed for surgical treatment of femoroacetabular impingement syndrome (FAIS) in the setting of acetabular retroversion. Purpose: (1) To report and analyze midterm patient-reported outcome scores (PROs) in patients with FAIS and labral tears in the setting of acetabular retroversion after isolated hip arthroscopy and (2) to compare these PROs with those of a propensity-matched control group without acetabular retroversion. Study Design: Cohort study; Level of evidence, 3. Methods: Prospectively collected data were retrospectively reviewed for patients who underwent hip arthroscopy for FAIS and labral tear treatment between June 2008 and March 2014. Inclusion criteria were as follows: acetabular retroversion, pre- and postoperative PROs for modified Harris Hip Score (mHHS), Non-arthritic Hip Score, Hip Outcome Score–Sports Specific Scale (HOS-SSS), and visual analog scale (VAS). Propensity score matching was utilized to identify a control group without acetabular retroversion matched 1:1 with similar age, sex, body mass index, acetabular and femoral head Outerbridge grade, preoperative lateral center-edge angle, and labral treatment. Patient acceptable symptomatic state (PASS) and/or minimal clinically important difference (MCID) for the mHHS, HOS-SSS, International Hip Outcome Tool–12, and VAS was calculated. Results: A total of 205 hips with acetabular retroversion were matched to a control group. The groups showed no difference in demographic variables. The retroversion group was composed of 139 female and 66 male hips, with a mean ± SD age of 23.81 ± 7.28 years and follow-up time of 65.24 ± 20.31 months. Intraoperative diagnostic data and procedures performed were similar between groups, except more femoroplasties were performed in the retroversion group. Significant improvements for the mHHS, Non-arthritic Hip Score, HOS-SSS, and VAS were seen for both groups at a mean 5-year follow-up. The proportion of patients who reached the PASS and MCID were similar. Conclusion: In the setting of FAIS and labral tears, patients with acetabular retroversion can be safely treated with advanced hip arthroscopic techniques without reverse (anteverting) periacetabular osteotomy in a high-volume surgeon’s hands. Patients with acetabular retroversion demonstrated favorable PROs at midterm follow-up. Furthermore, the proportion of patients reaching the MCID and PASS for several PROs were comparable with those of a propensity-matched control group without acetabular retroversion.

Spinopelvic Characteristics in Acetabular Retroversion: Does Pelvic Tilt Change After Periacetabular Osteotomy?

Background: Acetabular retroversion may lead to impingement and pain, which can be treated with an anteverting periacetabular osteotomy (aPAO). Pelvic tilt influences acetabular orientation; as pelvic tilt angle reduces, acetabular version reduces. Thus, acetabular retroversion may be a deformity secondary to abnormal pelvic tilt (functional retroversion) or an anatomic deformity of the acetabulum and the innominate bone (pelvic ring). Purpose: To (1) measure the spinopelvic morphology in patients with acetabular retroversion and (2) assess whether pelvic tilt changes after successful anteverting PAO (aPAO), thus testing whether preoperative pelvic tilt was compensatory. Study Design: Case series; Level of evidence, 4. Methods: A consecutive cohort of 48 hips (42 patients; 30 ± 7 years [mean ± SD]) with acetabular retroversion that underwent successful aPAO was studied. Spinopelvic morphology (pelvic tilt, pelvic incidence, anterior pelvic plane, and sacral slope) was measured from computed tomography scans including the sacral end plate in 21 patients, with adequate images. In addition, the change in pelvic tilt with aPAO was measured via the sacrofemoral-pubic angle with supine pelvic radiographs at an interval of 2.5 ± 2 years. Results: The spinopelvic characteristics included a pelvic tilt of 4° ± 4°, a sacral slope of 39° ± 9°, an anterior pelvic plane angle of 11° ± 5°, and a pelvic incidence of 42° ± 10°. Preoperative pelvic tilt was 4° ± 4° and did not change postoperatively (4° ± 4°) (P = .676). Conclusion: Pelvic tilt in acetabular retroversion was within normal parameters, illustrating “normal” sagittal pelvic balance and values similar to those reported in the literature in healthy subjects. In addition, it did not change after aPAO. Thus, acetabular retroversion was not secondary to a maladaptive pelvic tilt (functional retroversion). Further work is required to assess whether retroversion is a reflection of a pelvic morphological abnormality rather than an isolated acetabular abnormality. Treatment of acetabular retroversion should focus on correcting the deformity rather than attempting to change the functional pelvic position.

Functional acetabular retroversion syndrome: description of a specific sub-type of FAI and results of treatment with minimally invasive PAO.

Acetabular retroversion syndrome is associated with pincer-type femoroacetabular impingement (FAI) and results, theoretically, from an externally rotated hemipelvis. The purpose of this study was to examine our surgical experience and the clinical results of functional acetabular retroversion syndrome treated with minimally-invasive periacetabular osteotomy (PAO). We performed a retrospective cohort study of prospectively collected data in consecutive patients who had an anteverting PAO from 01 November 2010 to 31 December 2015. All patients were followed up clinically and radiologically.Functional scores were ascertained using pre- and postoperative iHOT-12 and EQ-5D. The effect of hypermobility, smoking status and body mass index (BMI) on outcome measures was evaluated. 31 anteverting PAOs were performed on 27 consecutive patients. All patients were female. The mean age was 26.7 years (SD 6.7). The mean BMI was 25.8 kg/m2 (SD 5.1). 5 patients were smokers (16.1%) and 11 exhibited signs of generalised joint laxity. 23 hips had undergone prior hip arthroscopy and 1 patient had previous open FAI surgery. The minimum clinical follow-up was 2 years (mean 3.4 years; range 2-7 years). A crossover sign was present in all cases. The mean iHOT-12 score improved from 19.5 to 51 at 6 months, 64.5 at 1 year and 48 at 2 years following surgery (p < 0.05) EQ-5D improved from 0.42 preoperatively to 0.76 at 6 months and 0.69 at 1 year following surgery (p < 0.05). We have characterised functional acetabular retroversion syndrome (FARS) as a condition affecting young, active females which severe symptoms out of proportion to demonstrable radiographic pathology.

Anteverting Bernese periacetabular osteotomy in the treatment of neurogenic hip dysplasia in cerebral palsy.

All patients with hypertonic cerebral palsy undergoing Bernese periacetabular osteotomy (PAO) between 2005 and 2014 were reviewed. Clinical and radiographic parameters, including the cerebral palsy hip classification and anterior and posterior wall indices were collected to assess acetabular reorientation. Twenty (83%) of 24 procedures involved the correction of posterolateral acetabular insufficiency and were 'anteverting PAOs'. All 20 experienced improvements in radiographic indices. Eleven (58%) of 19 PAOs in ambulatory patients were performed in the setting of other multilevel orthopedic surgery. The anteverting PAO is successful in correcting the posterolateral acetabular insufficiency present in spastic hip dysplasia, and can be performed in conjunction with a single-event multilevel surgery.

Modern Surgical Treatment of Recurrent Posterior Dislocation of the Native Hip.

Redislocation of the native hip is rare. An anterior fulcrum between the proximal part of the femur and the pelvis must be present for a posterior dislocation to occur. The purpose of this study is to describe the cases of 9 patients with posterior redislocation or recurrent subluxation of the native hip that was treated with hip preservation surgery. We retrospectively identified the cases of 9 patients, from 2 institutions, who had undergone hip preservation surgery for the management of posterior redislocation or recurrent subluxation of the native hip after a dislocation. The mean number of dislocations prior to surgery was 3.2 (range, 1 to 7). Pelvic radiographs were used to classify the acetabular morphology, sufficiency of acetabular containment, and structural anatomy of the proximal part of the femur. Radiographic identification of impinging structures was used to guide surgical treatment, which involved either femoral correction alone or the combination of femoral correction and an anteverting periacetabular osteotomy. At a mean follow-up of 73.8 months (range, 10 to 192 months), there had been no subsequent episodes of dislocation or subluxation in any of the hips treated with correction of the anatomic pivot point. An algorithmic approach is presented. In patients who have episodes of redislocation or recurrent subluxation of the native hip, the identification of anatomic abnormalities that create a fulcrum between the proximal part of the femur and the pelvis is critical for making appropriate treatment decisions. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Radiographic and Clinical Outcomes of Adolescents With Acetabular Retroversion Treated Arthroscopically.

Retroversion of the acetabulum is a cause of pincer impingement. Symptomatic retroversion has traditionally been treated with anteverting periacetabular osteotomy (PAO). However, arthroscopic rim trimming can also treat pincer impingement associated with acetabular retroversion. The purpose of this study was to report the outcomes and radiographic findings in a series of adolescent patients with symptomatic acetabular retroversion treated arthroscopically. Data were prospectively gathered at a single institution using an established hip preservation registry. Patients below 18 years with a retroverted acetabulum that underwent primary hip arthroscopy with 2-year follow-up were included. Acetabular retroversion was defined by 3 radiographic criteria: the presence of crossover, ischial spine sign, and posterior wall sign. Radiographic measurements of the lateral center-edge angle, anterior center-edge angle, alpha angle, and crossover percentage were reported preoperatively and postoperatively. Patient-reported outcome (PROs) measures included the modified Harris Hip Score, the non-Arthritic Hip Score, Hip Outcome Score Sports Subscale, visual analog scale, and patient satisfaction, recorded at 3 months, 1 year, and 2 years, postoperatively. In addition, International Hip Outcome Tool scores were gathered at 2 years. Between April 2008 and July 2014, there were 43 patients (48 hips) treated with hip arthroscopy who met the inclusion criteria. The average age was 16.1 years (range, 13.9 to 17.9 y) and there were 38 females and 10 males. The average follow-up was 50.4 months, with a minimum of 2 years. Statistically significant improvements in all PROs were found at 2 years postoperatively. There were 9 hips with lateral center-edge angle ≤25 degrees; the PROs of this group was not different than patients with normal coverage. Three patients underwent arthroscopic revision. No patient subsequently underwent anteverting PAO during the study period. There were no reported complications. Femoroacetabular impingement caused by acetabular retroversion treated with hip arthroscopy demonstrates good outcomes at 2 years with a low complication rate. Symptomatic adolescents may be safely and successfully treated arthroscopically, potentially avoiding anteverting PAO. Level of evidence 4-case series.

CORR Insights®: Periacetabular Osteotomy Provides Higher Survivorship Than Rim Trimming for Acetabular Retroversion.

CORR Insights®: Periacetabular Osteotomy Provides Higher Survivorship Than Rim Trimming for Acetabular Retroversion.