Periacetabular Osteotomy For Hip Dysplasia Research Articles

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

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

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.

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.

Incorporating patient-specific hip orientation from weightbearing computed tomography affects discrete element analysis-computed regional joint contact mechanics in individuals treated with periacetabular osteotomy for hip dysplasia.

Computational models of the hip often omit patient-specific functional orientation when placing imaging-derived bony geometry into anatomic landmark-based coordinate systems for application of joint loading schemes. The purpose of this study was to determine if this omission meaningfully alters computed contact mechanics. Discrete element analysis models were created from non-weightbearing (NWB) clinical CT scans of 10 hip dysplasia patients (11 hips) and oriented in the International Society of Biomechanics (ISB) coordinate system (NWB-ISB). Three additional models were generated for each hip by adding patient-specific stance information obtained via weightbearing CT (WBCT) to each ISB-oriented model: (1) patient-specific sagittal tilt added (WBCT-sagittal), (2) coronal and axial rotation from optical motion capture added to (1; WBCT-combo), and (3) WBCT-derived axial, sagittal, and coronal rotation added to (1; WBCT-original). Identical gait cycle loading was applied to all models for a given hip, and computed contact stress and contact area were compared between model initialization techniques. Addition of sagittal tilt did not significantly change whole-joint peak (p = 0.922) or mean (p = 0.871) contact stress or contact area (p = 0.638). Inclusion of motion-captured coronal and axial rotation (WBCT-combo) decreased peak contact stress (p = 0.014) and slightly increased average contact area (p = 0.071) from WBCT-sagittal models. Including all WBCT-derived rotations (WBCT-original) further reduced computed peak contact stress (p = 0.001) and significantly increased contact area (p = 0.001). Variably significant differences (p = 0.001-1.0) in patient-specific acetabular subregion mechanics indicate the importance of functional orientation incorporation for modeling applications in which local contact mechanics are of interest.

Analysis ofsurvivorship following periacetabular osteotomy forhip dysplasia based onthree-dimensional acetabular coverage.

Periacetabular osteotomy (PAO) is an established procedure for correcting acetabular coverage and preventing osteoarthritis progression in hip dysplasia. However, it is unclear how acetabular coverage changes three-dimensionally after PAO and how it affects survival. Therefore, this study aimed to investigate the change in three-dimensional acetabular coverage preoperatively and postoperatively and identify demographic, clinical and radiographic factors associated with conversion to total hip arthroplasty (THA) and radiographic osteoarthritis progression after PAO. We retrospectively reviewed 46 consecutive patients (66 hips) who underwent PAO, using preoperative and postoperative radiographs and pelvic computed tomography (CT). Three-dimensional acetabular coverage based on CT data was investigated. Kaplan-Meier survival analysis was performed, and hazard ratios were calculated using univariate Cox regression models to identify the risk factors associated with conversion to THA and radiographic osteoarthritis progression after PAO as the endpoints. Radiographic osteoarthritis progression was defined as a minimum joint space of <2.0 mm. The mean follow-up was 10.7 years. Post-PAO, acetabular coverage gradually increased from the anterosuperior to the superior to the posterosuperior direction. The survival rate after PAO was 98.0% at 10 years. Less postoperative superior acetabular coverage, with a hazard ratio of 0.93, was significantly associated with conversion to THA and radiographic osteoarthritis progression after PAO (P = 0.03). In this study, poor superior acetabular coverage after PAO was a significant risk factor for conversion to THA and radiographic progression of osteoarthritis. Therefore, surgeons should attempt to prioritize the correction of the superior acetabular coverage when performing PAO.

Periacetabular Osteotomy for Hip Dysplasia in a NCAA Division I Female Water Polo Athlete

OBJECTIVES The purpose of this study is to investigate the effect of applying a very minimal weight bearing in the early phase of a general rehabilitation program for returning to sports after periacetabular osteotomy for developmental dysplasia of the hip in physically active populations.METHODS A 22 year-old NCAA Division I female water polo player, with no prior history of hip injury and no signs of developmental dysplasia of the hip (DDH), reported to athletic training facility early season complaining of right hip pain after stationary bike workout. The athlete reported hearing and feeling a sudden “pop” within the right hip with immediate hip pain when she was pedaling at moderate intensity of a stationary bike. Numbness and tingling was felt initially with the mechanism. Tender to palpate at the right hip flexor and anterior hip joint, as well as the greater trochanter. The athlete’s chief complaints were pain with walking and prolonged sitting. Antalgic gait noticed during evaluation. A 6-, 12-, and 24-week rehabilitation protocol were performed.RESULTS X-ray and MRI images showed no avascular necrosis or fracture. An abnormal alpha angle found and no bursitis or tendonitis was shown. A periacetabular osteotomy (PAO) was performed to rotate the acetabular fragment into optimal position and fixed to the pelvis with 3 screws. During the initial 6-week of post-surgical rehabilitation, the level of pain and edema were minimized, the athlete was able to perform toe-touch and partial weight-bearing with crutches, and restored hip ROMs. From 6 to 10 weeks, the athlete recovered full hip ROMs and able to perform lunges, leg press, deadlifts, mini squats back to pre-injury status. The athlete was able to return to activities of daily living (ADLs) after 12 weeks. At 24 weeks, the athlete was able to fully participate in sports without limitations.CONCLUSIONS This case describes the rehabilitation program employed following PAO for an atypical case of DDH in a water polo athlete who had no signs and symptoms of DDH prior to sports participation. At the end of the season, the athlete opted to undergo PAO given the risks and underwent a 6-month rehabilitation before a full return to function. This case report aides with treatment knowledge and postsurgical rehabilitation techniques for athletic trainers.

Can we determine anterior hip coverage from pelvic anteroposterior radiographs? A study of patients with hip dysplasia

PurposeInsufficient coverage causes hip joint instability and results in hip pain. Anterior hip coverage can be determined on both pelvic anteroposterior (AP) radiographs and false profile (FP) radiographs. Four parameters are commonly used to determine the anterior coverage on pelvic AP radiographs: the crossover index, crossover sign, anterior wall index (AWI), and rule of thirds. This study aims to clarify the relationship between these 4 parameters on AP radiographs and the anterior center edge angle (ACEA) on FP radiographs.MethodsIn this study, 53 patients who underwent periacetabular osteotomy for hip dysplasia at our center between July 2020 and October 2020 were retrospectively reviewed. Four parameters on AP radiographs and the ACEA on FP radiographs before surgery and 6 months after surgery were measured and compared for each hip.ResultsUpon examining the 53 hips in this study, there was no correlation between either the crossover index and the ACEA (P = 0.66) or the crossover sign before surgery. The postoperative correlation between the crossover index and the ACEA was weak (r = 0.36, P = 0.007), and that between the crossover sign and the ACEA was moderate (r = 0.41, P = 0.003). There was a weak correlation between the AWI and ACEA both before (r = 0.288, P = 0.036) and after (r = 0.349, P = 0.011) the operation. Evaluation of the anterior coverage by the rule of thirds was also not consistent when determining the anterior coverage with the ACEA.ConclusionAnterior coverage on AP radiographs is largely inconsistent with ACEA on FP radiographs, especially before the surgery. It is recommended to take FP radiographs routinely for determining anterior hip coverage.

Fifty percent of patients undergoing periacetabular osteotomy for hip dysplasia showed normal findings upon neonatal ultrasound screening

Developmental dysplasia of the hip (DDH) is characterized by the pathomorphology of inadequate acetabular coverage of the femoral head leading to increased loading of the articular surface and acetabular rim. If left untreated, this ultimately leads to osteoarthritis. Germany introduced anationwide universal ultrasound screening program for all newborn infants in 1996. Subsequently, the incidence of undiagnosed hip dislocation was significantly reduced. In this consecutive series of patients who underwent periacetabular osteotomy for the treatment of symptomatic dysplasia of the hip between October 2014 and October 2022 data regarding the U3screening examination were analyzed. The data included whether the examination was performed, whether the findings were positive or negative, whether the patients underwent any form of treatment in the case of apositive finding and whether acontrol X‑ray was performed. This study provides evidence that acetabular undercoverage cannot be ruled out based on anormal finding in ultrasonography screening. Furthermore, the study also shows that residual dysplasia may persist despite attempts of conservative treatment.

Patient-Reported Outcomes Are Similar in the First 2 Years After Staged Versus Combined Hip Arthroscopy and Periacetabular Osteotomy for Hip Dysplasia

The purpose of this study was to compare early patient-reported outcomes after staged versus combined hip arthroscopy and periacetabular osteotomy for hip dysplasia. A prospective database was retrospectively reviewed to identify patients that underwent combined or staged hip arthroscopy and periacetabular osteotomy (PAO) from 2012 to 2020. Patients were excluded if they were >40 years of age, had prior ipsilateral hip surgery, or did not have at least 12-24 months of postoperative patient-reported outcome (PRO) data. PROs included the Hip Outcomes Score (HOS) Activities of Daily Living (ADL) and Sports Subscale (SS), Non-Arthritic Hip Score (NAHS), and the Modified Harris Hip Score (mHHS). Paired t-tests were used to compare preoperative to postoperative scores for both groups. Outcomes were compared using linear regression adjusted for baseline characteristics, including age, obesity, cartilage damage, acetabular index, and procedure timing (early vs late practice). Sixty-two hips were included in this analysis (39 combined, 23 staged). The average length of follow-up was similar between the combined and staged groups (20.8 vs 19.6 months; P= .192). Both groups reported significant improvements in PROs at final follow up compared to preoperative scores (P < .05 for all). There were no significant differences in HOS-ADL, HOS-SS, NAHS, or mHHS scores between groups preoperatively or at 3, 6, or 12 months postoperatively (P > .05 for all). There was no significant difference in PROs between the combined and staged groups at the final postoperative time point: HOS-ADL (84.5 vs 84.3; P= .77), HOS-SS (76.0 vs 79.2; P= .68), NAHS (82.2 vs 84.5; P= .79), and mHHS (71.0 vs 71.0, P= .75), respectively. Staged hip arthroscopy and PAO for hip dysplasia leads to similar PROs at 12-24 months compared to combined procedures. This suggests that with careful and informed patient selection, staging these procedures is an acceptable option for these patients and does not change early outcomes. Level III, retrospective comparative.

The economics of patients undergoing periacetabular osteotomy for hip dysplasia: the financial relationship between physicians and hospitals.

Periacetabular osteotomy (PAO) is the gold standard for treating hip dysplasia in patients with preserved articular cartilage. The aim of this study is to evaluate the financial relationship between facility and professional revenue for patients undergoing PAO for hip dysplasia and acetabular version abnormalities. All patients who underwent PAO for hip dysplasia by a single surgeon at a tertiary academic medical center between December 2016 and November 2020 were identified. Financial records for facility and professional services were reviewed and analyzed. The orthopedic charge multiplier, the dollars of facility charge created by a single dollar of orthopedic professional charge, and orthopedic net revenue multiplier, the dollars collected by the hospital for facility services generated for each dollar collected by the orthopedic surgeon, were calculated. A total of 36 patients were included in the study. The mean total charge for all patients was $144 939.35 ± $23 726.48 (range $109 002.71 to $227 290.20), and the average total revenue for all patients was $44 218.79 ± $12 352.97 (range $29 397.39 to $90,830.62). The mean orthopedic charge multiplier was 2.47 ± 1.32 (range 0.78-6.53), and the net revenue collection multiplier was 8.62 ± 10.69 (range, 1.20-57.80). The majority of charges and revenue related to care of patients undergoing PAO return to the hospital. The significant mean orthopedic charge multiplier for this procedure increases the value of the service and the surgeon to hospital profitability. This information can help shape the relationship between the hospital and the surgeon and create a firm platform to advocate for program advancement.

Comparison of modern periacetabular osteotomy for hip dysplasia with total hip arthroplasty for hip osteoarthritis-10-year outcomes are comparable in young adult patients.

ABSTRACTYoung adult patients with symptomatic acetabular dysplasia and marginal secondary osteoarthritis can be faced with the decision to either undergo periacetabular osteotomy (PAO) to relieve symptoms and slow osteoarthritis progression or wait until progression to more advanced disease and undergo total hip arthroplasty (THA). The decision can be difficult, and contemporary literature to guide these decisions is sparse. Therefore, we retrospectively assessed complication rate, survivorship and patient-reported clinical outcomes [modified Harris Hip score (mHHS), UCLA Activity score] in two, consecutive cohorts of patients aged 18–40 years that underwent either PAO for symptomatic acetabular dysplasia (mean age 28.9 years) or THA for advanced secondary osteoarthritis (32.5 years). PAO patients were followed for a mean of 10.5 years (8–19) and THA patients for 11.9 (8–17) years. Between PAO and THA groups, there were no differences in overall complication rate (4.7% versus 4.7%), non-revision reoperation rate (5.9% versus 2.3%, P = 0.37) or end-revision rate [7 (8.2%) PAOs converted to THA at mean 10.8 years versus 3 (7.0%) THAs revised at 6.2 years, P = 0.80]. Latest scores remained significantly improved from baseline in both the PAO (mHHS 86.1 versus 63.3, P < 0.001; UCLA 7.5 versus 6.9, P < 0.05) and THA (mHHS 82.6 versus 48.4, P < 0.001; UCLA 7.2 versus 4.6, P < 0.001) cohorts. Final scores were similar between groups (mHHS 86.1 versus 82.6, P = 0.46; UCLA 7.5 versus 7.2, P = 0.37). Clinical success [mHHS minimal clinically important difference (8) OR PASS (>70) at latest follow-up without end-revision] was achieved in 81.2% of PAO hips and 83.7% of THA hips (P = 0.72).

Capsular Mechanics After Periacetabular Osteotomy for Hip Dysplasia.

Hip dysplasia is characterized by insufficient acetabular coverage around the femoral head, which leads to instability, pain, and injury. Periacetabular osteotomy (PAO) aims to restore acetabular coverage and function, but its effects on capsular mechanics and joint stability are still unclear. The purpose of this study was to examine the effects of PAO on capsular mechanics and joint range of motion in dysplastic hips. Twelve cadaveric dysplastic hips (denuded to bone and capsule) were mounted onto a robotic tester and tested in multiple positions: (1) full extension, (2) neutral 0°, (3) flexion of 30°, (4) flexion of 60°, and (5) flexion of 90°. In each position, the hips underwent internal and external rotation, abduction, and adduction using 5 Nm of torque. Each hip then underwent PAO to reorient the acetabular fragment, preserving the capsular ligaments, and was retested. The PAO reduced internal rotation in flexion of 90° (∆IR = -5°; p = 0.003), and increased external rotation in flexion of 60° (∆ER = +7°; p = 0.001) and flexion of 90° (∆ER = +11°; p = 0.001). The PAO also reduced abduction in extension (∆ABD = -10°; p = 0.002), neutral 0° (∆ABD = -7°; p = 0.001), and flexion of 30° (∆ABD = -8°; p = 0.001), but increased adduction in neutral 0° (∆ADD = +9°; p = 0.001), flexion of 30° (∆ADD = +11°; p = 0.002), and flexion of 60° (∆ADD = +11°; p = 0.003). PAO caused reductions in hip abduction and internal rotation but greater increases in hip adduction and external rotation. The osseous acetabular structure and capsule both play a role in the balance between joint mobility and stability after PAO.

Single Table Concomitant Post-Less Hip Arthroscopy Combined with Periacetabular Osteotomy for Hip Dysplasia

It has been well established that both arthroscopic and open hip preservation techniques can result in improved patient outcomes and interrupt the natural history of hip disease. Traditionally, hip arthroscopy has been used to address central and peripheral compartment disease consisting of labral tears, impingement morphology and cartilage pathology. The periacetabular osteotomy has been the most used treatment for hip instability caused by inadequate acetabular coverage of the femoral head or dysplasia. With failures of periacetabular osteotomy linked to postoperative impingement and the high incidence of intra-articular pathology in the dysplastic hip, there has been a great interest in combing hip arthroscopy with the periacetabular osteotomy. Here, we describe a technique for a single table, single drape, postless combined hip arthroscopy, and periacetabular osteotomy.

Acetabular retroversion in dysplastic hips is associated with decreased 3Dfemoral head coverage independently from lateral center-edge angle.

The clinical significance of acetabular retroversion in non-dysplastic hips can be explained as pincer-type femoroacetabular impingement (FAI), whereas that in dysplastic hips is not clarified because FAI normally poses little problems for dysplastic hips. We aimed to evaluate three-dimensional (3D) femoral head coverage in dysplastic hips with and without acetabular retroversion and to elucidate the role of acetabular retroversion on the 3D femoral head coverage. We retrospectively investigated 93 hips in 93 patients (9 males and 84 females) that underwent periacetabular osteotomy for hip dysplasia. Dysplastic hips were divided into anteversion and retroversion groups according to their cranial anteversion, which was measured on the axial section 5mm caudal to the acetabular roof. The 3D femoral head coverage was provided as a percentage of the acetabulum-covered surface area of the upper femoral hemisphere using a 3D preoperative planning software for total hip arthroplasty. Of the 93 dysplastic hips, 15 hips (16%) were assignedto the retroversion group, which had significantly younger age at surgery (31.9years versus 39.2years; p = 0.033). The lateral center-edge angles were comparable between the groups (13.8° versus 12.9°; p = 0.68); however, the hips in the retroversion group had a trend of smaller 3D femoral head coverage than those in the anteversion group (59% versus 63%; p = 0.058). Multivariate analysis using two-way analysis of covariance showed that lateral center-edge angle (partial regression coefficient = 0.83; t value = 17.3; p < 0.001) and acetabular retroversion (partial regression coefficient = - 2.3; t value = - 4.9; p < 0.001) were independent factors that contributed to the 3D femoral head coverage. Acetabular retroversion in dysplastic hips was associated with decreased 3D femoral head coverage independently from lateral center-edge angle. The age at surgery in the retroversion group was significantlyyounger, suggesting a relationship between decreased 3D coverage and potentially earlier symptom onset.

Unaddressed Cam Deformity Is Associated with Elevated Joint Contact Stress After Periacetabular Osteotomy

Femoral cam deformity is frequently present in patients with acetabular dysplasia. Computational modeling can be used to identify how this deformity affects joint mechanics. Our purpose was to identify the relationship between cam deformity and joint contact stress after periacetabular osteotomy (PAO). We hypothesized that cam deformity is associated with an increase in peak joint contact stress after PAO. This was a retrospective review of patients treated for hip dysplasia with PAO without femoral osteochondroplasty. Patient-specific hip models created from preoperative and postoperative computed tomography (CT) scans were evaluated using discrete element analysis to determine maximum joint contact stress after PAO. Twenty hips with a postoperative increase in maximum contact stress were compared with 20 that demonstrated decreased maximum contact stress. Hips were assessed for cam deformity on cross-sectional imaging. Radiographic measures of acetabular dysplasia before and after PAO were assessed and compared with the change in maximum contact stress after PAO. There was a moderate relationship between the change in maximum contact stress and the α angle (r = 0.31; p = 0.04), and the average α angle in the hips with increased maximum contact stress was significantly different from that in the hips with decreased joint contact stress (51° ± 11.4° versus 42° ± 5.1°; p = 0.04). All 6 hips with an α angle of >60° demonstrated increased joint contact stress. Cam deformity is common in patients with hip dysplasia. In our study, α angles of >60° were associated with increased postoperative joint contact stress. The α angle should be assessed preoperatively, and deformity should be addressed for optimal joint mechanics after PAO. A reduction in joint contact stress is a proposed mechanism for the increased joint longevity following periacetabular osteotomy for hip dysplasia. Impingement from abnormal femoral offset negatively impacts clinical outcome, but this finding has not been evaluated from a biomechanical perspective previously and a threshold for performing femoral osteochondroplasty has not been established previously. This study provides biomechanical evidence supporting surgical management of femoral cam deformity for an α angle of >60°.

Concomitant Arthroscopy With Labral Reconstruction and Periacetabular Osteotomy for Hip Dysplasia

In the setting of true hip dysplasia, the high prevalence of intra-articular pathology may lead to recurrent symptoms and failure after periacetabular osteotomy (PAO). Femoral neck osteochondroplasty, microfracture, removal of loose bodies, and labral repair are examples of procedures that are performed with concomitant arthroscopy. When damage to the labrum is too severe to repair, reconstruction instead of extensive debridement before PAO can be more effective in restoring the labral seal to maintain joint lubrication and chondral protection. This Technical Note describes a method for concomitant hip arthroscopy with circumferential labral reconstruction with allograft and PAO.

What is The Impact of PAO Surgery on Patient Function and Activity Levels?

Objectives:The Bernese periacetabular osteotomy (PAO) is becoming a widely utilized procedure. Patients are younger, highly active, and may desire to return to sport activity. Counseling and managing expectations in these patients is challenging as there is limited information regarding activity level after PAO. The purpose of this study was to analyze physical activity levels after PAO in a large, prospective multicenter cohort.Methods:Assessment of prospectively collected data from a multicenter group included 456 hips treated by PAO for hip dysplasia. After exclusions, 359 hips (80 male, 279 female) remained with a mean age of 25.9 years and mean BMI of 25. Demographics, radiographic measures, and clinical outcomes were evaluated preoperatively, at 1 year follow-up, and at minimum 2 years postoperatively (mean 44.9 months). Activity level was assessed with the University of California-Los Angeles (UCLA) activity score, patients were stratified into low, moderate, and high activity groups based on preoperative function. Descriptive statistics and linear regressions were performed for the primary outcome of change in UCLA.Results:UCLA scores were improved on average 0.6 points at final follow up (p = 0.001). When stratified, the low activity and moderate activity groups had significant improvement in UCLA scores (p<.0001 and p=0007) while the high activity group saw a decrease in UCLA scores (p<.0001). mHHS, HOOS Pain, and HOOS Sports and Recreation scores were significantly improved across all activity levels. Univariable linear regression analysis identified prior ipsilateral surgery, arthroscopy at time of PAO, and preoperative ACEA to be predictors of the change in UCLA score (p<0.05). With the multivariable model, the effect of prior ispilateral surgery was maintained (p = 0.002).Conclusion:The data suggests that improvements in activity level and function can be expected following PAO surgery, with greater gains experienced by patients with lower preoperative level of activity.Figure 1.Change in UCLA activity score after PAO, stratified by preoperative activity.Figure 2.Change in Modified Harris Hip (mHHS), the Hip disability and Osteoarthritis Outcome Score (HOOS) pain subscore and HOOS sports and recreation subscore, stratified by preoperative activity.

Surgical treatments for osteoarthritis

There are two main surgical treatments for osteoarthritis: conservative treatments, where the damaged cartilage is left in place, and radical treatments, where the cartilage is replaced by an artificial endoprosthesis; this latter procedure is termed joint arthroplasty. These treatments are only offered to symptomatic patients. Arthrodesis is yet another surgical intervention in cases of osteoarthritis. It will sacrifice the joint's articular function and is performed on small osteoarthritic joints, such as wrists and ankles, for instance. Osteoarthritis symptoms are usually the consequence of an imbalance between the load applied to a joint and the surface available to support that load. Therefore, conservative treatments will either tend to decrease the load exerted on the joint, such as in a tibial valgus osteotomy for instance, or to improve the articular surface supporting that load. Sometimes, both can be provided at the same time; the peri-acetabular osteotomy for hip dysplasia is an example of such a procedure. Conservative treatments are usually offered to young patients in order to delay, if not avoid, the need for a joint prosthesis. They are usually performed before osteoarthritis appears or at an early stage. Joint arthroplasties have overwhelmingly excellent functional results and today's research is directed towards providing rapid recovery, very long-term stability, and the assurance of a good functionality in extreme conditions. However, complications with joint arthroplasties can be serious with little, if any, reasonable salvage solution. Therefore, these procedures are offered to patients who have failed adequate medical treatment measures.

Bernese periacetabular osteotomy for hip dysplasia: Surgical technique and indications.

For young, active patients with healthy hip cartilage, pelvic osteotomy is a surgical option in to address hip pain and to improve mechanical loading conditions related to dysplasia. Hip dysplasia may lead to arthrosis at an early age due to poor coverage of the femoral head and abnormal loading of the joint articulation. In patients with symptomatic dysplasia and closed triradiate cartilage (generally over age 10), including adolescents and young adults (generally up to around age 40), the Bernese periacetabular osteotomy (PAO) is a durable technique for addressing underlying structural deformity. The PAO involves a modified Smith-Petersen approach. Advantages of the Bernese osteotomy include preservation of the weight-bearing posterior column of the hemi-pelvis, preservation of the acetabular blood supply, maintenance of the hip abductor musculature, and the ability to effect powerful deformity correction about an ideal center of rotation. There is an increasing body of evidence that preservation of the native hip can be improved through pelvic osteotomy. In contrast to hip osteotomy and joint preservation, the role of total hip arthroplasty in young, active patients with correctable hip deformity remains controversial. Moreover, the durability of hip replacement in young patients is inherently limited. Pelvic osteotomy should be considered the preferred method to address correctable structural deformity of the hip in the young, active patient with developmental dysplasia. The Bernese PAO is technically demanding, yet offers reproducible results with good long-term survivorship in carefully selected patients with preserved cartilage and the ability to meet the demands of rehabilitation.

Outcome of peri-acetabular osteotomy for hip dysplasia in teenagers.

Peri-acetabular osteotomy, especially curved peri-acetabular osteotomy, is an effective surgical procedure for re-orientating the acetabulum. However, there have been few reports on this procedure in teenagers. The purpose of this study was to investigate the treatment outcomes of curved peri-acetabular osteotomy in teenagers. We retrospectively reviewed 33 hips in 27 teenage patients with acetabular dysplasia who underwent curved peri-acetabular osteotomy between 1995 and 2012. The mean age was 17.0 years (range, 14-19 years). The mean follow-up duration at the most recent physical examination was 33.3 months (range, 24-96 months). All hips were evaluated in terms of the Harris hip score, radiographic measurements, and complications. The mean Harris hip score improved from 80.1 points pre-operatively to 95.4 points post-operatively (p < 0.001). There were significant differences in all of the radiographic measurements between the pre-operative and post-operative values (p < 0.001). One major complication occurred (symptomatic ischial nonunion) and required subsequent surgery. Nine hips had minor complications, including nonunion of the superior ramus osteotomy (four hips), superficial stitch abscess (two hips), and transient lateral femoral cutaneous nerve palsy (three hips). Satisfactory results can be obtained clinically and radiographically after curved peri-acetabular osteotomy in adolescents. Osteotomy for acetabular dysplasia is effective in teenagers.