Survivorship of the Bernese Periacetabular Osteotomy: What Factors are Associated with Long-term Failure?

The Principles of Hip Joint Preservation

The three primary factors involved in preservation of the hip joint include femoroacetabular impingement (FAI), hip dysplasia/instability, and femoral torsion abnormalities. Each of these factors affects the health of the acetabular labrum and femoroacetabular cartilage. The appropriate surgical treatments for each of these factors include arthroscopic or open femoroplasty/acetabuloplasty for FAI, periacetabular osteotomy for hip dysplasia/instability, and derotational femoral osteotomy for femoral torsion abnormalities. When evaluating patients with prearthritic hip conditions, orthopaedic surgeons should be aware of the various factors involved in hip joint preservation and, if surgery is indicated, the surgeon should be sure to address all factors that need surgical treatment rather than focusing on the commonly diagnosed issue or visible injury, for example, a labral tear. If any of these factors is ignored, the hip joint may not thrive. The purpose of this review was to explain the importance of the most common factors involved in hip joint preservation and the appropriate surgical treatments for pathology in these factors.

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

Purpose

To analyze the annual use of hip arthroscopy (HA) and Bernese periacetabular osteotomy (PAO) for the treatment of hip dysplasia (HD), as well as postoperative outcomes, including ipsilateral reoperations.

Methods

International Classification of Diseases, Ninth and Tenth Revision, codes were used to query the PearlDiver Mariner database from January 2010 through January 2022 to identify patients aged 10 to 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 after HA). We analyzed annual rates for each treatment, as well as rates of postoperative emergency visits, readmissions, and 5-year ipsilateral secondary operations (determined via Kaplan-Meier analysis).

Results

There 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 greatest percent-increase from 2015 to 2016. HA and HA-PAO peaked in 2021, whereas PAO peaked in 2019. For HA, PAO, and HA-PAO, most cases were performed in female patients and patients aged 30 to 49 years, 10 to 19 years, and 10 to 29 years, respectively. The 5-year incidence of ipsilateral secondary operations, which include revision HA, PAO, or conversion to total hip arthroplasty, was 9.2% (95% confidence interval 8.6%-9.8%) in the HA group and 6.5% (95% confidence interval 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 greatest 30-day emergency visit and 90-day readmission rates, with infection as the most common cause for readmission.

Conclusions

HA is more frequently performed than PAO for hip dysplasia. HA-PAO is increasing at the greatest rate, demonstrating fewer complications and reoperations.

Level of Evidence

Level III, retrospective comparative trial.

A 30-year follow-up study of rotational acetabular osteotomy for pre- and early-stage osteoarthritis secondary to dysplasia of the hip

Aims

The objective of this study was to present the outcomes of rotational acetabular osteotomy (RAO) over a 30-year period for osteoarthritis (OA) secondary to dysplasia of the hip in pre- or early-stage OA.

Methods

Between September 1987 and December 1994, we provided treatment to 47 patients (55 hips) with RAO for the management of pre- or early-stage OA due to developmental hip dysplasia. Of those, eight patients (11 hips) with pre-OA (follow-up rate 79%) and 27 patients (32 hips) with early-stage OA (follow-up rate 78%), totalling 35 patients (43 hips) (follow-up rate 78%), were available at a minimum of 28 years after surgery.

Results

In the pre-OA group, the mean Merle d'Aubigné score improved significantly from 14.5 points (SD 0.7) preoperatively to 17.4 points at final follow-up (SD 1.2; p = 0.004) and in the early-stage group, the mean score did not improve significantly from 14.0 (SD 0.3) to 14.6 (SD 2.4; p = 0.280). Radiologically, the centre-edge angle, acetabular roof angle, and head lateralization index were significantly improved postoperatively in both groups. Radiological progression of OA was observed in two patients (two hips) in the pre-OA group and 17 patients (18 hips) in the early-stage group. Kaplan-Meier survival analysis, with radiological progression of OA as the primary outcome, projected a 30-year survival rate of 81.8% (95% confidence interval (CI) 0.59 to 1.00) for the pre-OA group and 42.2% (95% CI 0.244 to 0.600) for the early-stage group. In all cases, the overall survival rate stood at 51.5% (95% CI 0.365 to 0.674) over a 30-year period, and when the endpoint was conversion to total hip arthroplasty, the survival rate was 74.0% (95% CI 0.608 to 0.873).

Conclusion

For younger patients with pre-OA, joint preservation of over 30 years can be expected after RAO.

Retroverting Periacetabular Osteotomy for Symptomatic Acetabular Anteversion

BACKGROUND

Acetabular dysplasia has traditionally been defined using the lateral center edge angle and treated with periacetabular osteotomy (PAO). However, the recently described Ottawa classification further quantifies dysplasia in 3-dimensional terms, categorizing Ottawa A as dysplasia due to isolated, excessive acetabular anteversion or anterior acetabular under-coverage. We sought to determine if patients who have Ottawa A dysplasia can expect similar outcomes when undergoing a PAO compared to a traditional dysplasia cohort.

METHODS

Patients who had undergone PAO with Ottawa A hip dysplasia were selected and compared to a control group of patients who had lateral acetabular undercoverage. The modified Harris Hip Score and International Hip Outcome Tool-33 were collected preoperatively and at various follow-up points for a final follow-up average of 2.3 years (range, 0.9 to 6.2).

RESULTS

The 17 patients (21 hips) who had Ottawa A dysplasia were compared to a control cohort of 69 patients (88 hips). Both groups saw significant improvements in modified Harris Hip Score and International Hip Outcome Tool-33 at final follow-up, P < .001. There were no differences between groups in any of the outcome measures or rates of achieving minimal clinically important difference (MCID) or substantial clinical benefit. Rates of MCID ranged from 82.4 to 100%, and rates of achieving substantial clinical benefit ranged from 47.1 to 52.9%.

CONCLUSIONS

In patients undergoing a PAO for Ottawa A hip dysplasia, a significant improvement in patient-reported outcomes can be expected with high rates of MCID achievement. This is not significantly different for patients undergoing PAO for more traditional dysplasia parameters.

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

BACKGROUND

There is no consensus regarding the treatment of symptomatic hip dysplasia in adolescents and adults. Most previous studies have insufficient follow-up time.

AIM

The aim of this study was to assess the long-term outcome of a modified Spitzy shelf procedure.

METHODS

We reviewed 79 adults with 94 acetabular shelf operations between 1976 and 2000. Mean age at surgery was 33.7 years (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.

RESULTS

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 54.3 years (range 29-76). The mean survival time from Spitzy operation to THR was 17.2 years (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 ≥ 30 years and preoperative osteoarthritis (OA). The rate of complications was 12%, but most were mild to moderate.

CONCLUSIONS

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.

Periacetabular osteotomy for symptomatic hip dysplasia in middle aged patients: does age alone matter?

BACKGROUND

Conflicting evidence exists regarding outcomes in middle-aged patients undergoing periacetabular osteotomy (PAO) for symptomatic developmental dysplasia of the hip (DDH).

AIMS

To compare patient reported outcomes (PROMs) of middle-aged PAO patients with younger patient groups.

METHODS

Retrospective analysis of prospectively collected data of PAO patients between 01/2015 and 06/2017 at a single orthopedic university center with a primary diagnosis of symptomatic DDH. The cohort was divided into four age groups and compared: < 20, 20-30, 30-40 and > 40 years. Joint function was assessed using iHOT-12, mHHS and SHV. Activity level was assessed using UCLA Activity score. Patient satisfaction and pain were assessed on the numerical rating scale 0-10. Conversion rates to THA were assessed.

RESULTS

Out of 202 PAOs, 120 cases with complete data were included. Mean follow-up was 63 months (range 47-81 months). Eighteen patients were < 20 years old, 54 were 20-30 years, 37 were 30-40 years, 11 patients were older than 40. No significant differences were observed for preoperative or postoperative iHOT-12 (p = 0.898; p = 0.087), mHHS (p = 0.878; p = 0.103), SHV (p = 0.602; p = 0.352) or UCLA (p = 0.539; p = 0.978) between groups. Improvement deltas were also not significantly different for all PROMs. Postoperative patient satisfaction was similar between groups (p = 0.783).

CONCLUSION

Patients with symptomatic DDH may benefit from PAO even at middle age with similar outcomes and pre- to postoperative improvements as younger age groups. Indication should be based on biological age and preoperative joint condition rather than age.

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

BACKGROUND

The 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.

METHODS

Facebook, 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.

RESULTS

Two 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%).

CONCLUSION

The 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.

In Vitro Investigation of Column Fixation Constructs for Periacetabular Osteotomy: Which Provide the Greatest Stiffness and Strength?

Background

Periacetabular osteotomy (PAO) is an effective surgical procedure for managing acetabular dysplasia. The purpose of this study was to analyze the biomechanical properties of novel PAO constructs that incorporate orthopaedic trauma techniques. We hypothesize that these fixation methods will create a stiffer construct that tolerates higher loads to failure.

Methods

Twenty bio-composite hemi-pelvises underwent PAO with the following fixation configurations: Group A: 4 iliac crest (IC) screws; Group B: 3 IC screws; Group C: 2 IC screws, 1 retrograde anterior column (AC) screw, and 1 lateral compression type-2 (LC2) screw directed from the anterior inferior iliac spine to the posterior inferior iliac spine; Group D: 1 AC screw, 1 LC2 screw, 1 posterior column screw; Group E: 2 LC2 screws, 1 AC screw. Constructs were loaded to failure on a material testing hydraulic press, and ultimate strength, stiffness, and osteotomy displacement were measured.

Results

The highest load to failure was seen in group D (2511 N), which was significantly more than groups A (1528 N, P = .0114) and B (1348 N, P < .0001). The stiffest construct was group E (602 N/mm) compared to groups A (315 N/mm, P = .0439) and B (243 N/mm, P = .0008). Failure occurred most often with a fracture in the posterior column.

Conclusions

This study supports column fixation methods used in orthopaedic trauma for PAO as biomechanically advantageous to traditional fixation techniques. These constructs may be beneficial to patients with weight-bearing concerns or early rehabilitation needs.

Perceived outcomes of periacetabular osteotomy

Aims

Social media is a popular resource for patients seeking medical information and sharing experiences. periacetabular osteotomy (PAO) is the gold-standard treatment for symptomatic acetabular dysplasia with good long-term outcomes. However, little is known regarding the perceived outcomes of PAO on social media. The aims of this study were to describe the perceived outcomes following PAO using three social media platforms: Facebook, Instagram, and X (formerly known as Twitter).

Methods

Facebook, Instagram, and X posts were retrospectively collected from 1 February 2023. Facebook posts were collected from the two most populated interest groups: "periacetabular osteotomy" and "PAO Australia." Instagram and X posts were queried using the most popular hashtags: #PAOwarrior, #periacetabularosteotomy, #periacetabularosteotomyrecovery, #PAOsurgery, and #PAOrecovery. Posts were assessed for demographic data (sex, race, location), perspective (patient, physician, professional organization, industry), timing (preoperative vs postoperative), and perceived outcome (positive, negative, neutral).

Results

A total of 1,054 Facebook posts, 1,003 Instagram posts, and 502 X posts were consecutively assessed from 887 unique authors. The majority (63.3%) of these posts were from patients in the postoperative period, with a median of 84 days postoperatively (interquartile range 20 to 275). The longest follow-up timeframe postoperatively was 20 years. Regarding perceived outcomes, 52.8% expressed satisfaction, 39.7% held neutral opinions, and 7.5% were dissatisfied. Most dissatisfied patients (50.9%) reported pain (chronic or uncontrolled acute) as an attributing factor.

Conclusion

Most PAO-perceived surgical outcomes on social media had a positive tone. Findings also indicate that a small percentage of patients reported negative perceived outcomes. However, dissatisfaction with PAO primarily stemmed from postoperative pain. Social media posts from other sources (physicians, hospitals, professional organizations, etc.) trend towards neutrality. Healthcare providers must consider the social media narratives of patients following PAO, as they may reveal additional outcome expectations and help improve patient-centred care, create informed decision-making, and optimize treatment outcomes.

Peri-Operative Management of Periacetabular Osteotomy: A Report of Current Practices from the Anchor Group, Supporting Literature, and Areas for Future Investigation

Background

Periacetabular osteotomy (PAO) is a well-established surgical treatment for hip dysplasia, but very few studies report the impact of peri-operative management strategies on early pain and function. The purpose of this study is to describe peri-operative management variability among a group of experienced surgeons and review the literature supporting these practice patterns.

Methods

We surveyed 16 surgeons that perform PAO to document various aspects of peri-operative management at four stages: pre-operative, intra-operative, post-operative in the hospital, and at discharge. Our goal was to report current surgical pain management strategies, adjunct medications, type of anesthesia, deep venous thrombosis and heterotopic ossification prophylaxis strategies, initiation of physical therapy, and use of continuous passive motion (CPM). We reviewed current literature to identify studies supporting these perioperative strategies and identify knowledge gaps that would benefit from further investigation.

Results

Of the 16 surgeons surveyed, 75% had been in practice greater than 10 years and most had not altered their post-operative protocol for more than 3 years. 15/16 surgeons felt that length of stay could be reduced at their institution with improved peri-operative pain management. 6/16 were considering or had already implemented outpatient PAO as a part of their practice. We found significant variability in the pain medications provided at all peri-operative stages. 14/16 utilized general anesthesia, and many utilized epidural or peripheral nerve blocks. 6/16 surgeons utilized surgical field block (also referred to as periarticular block). These surgeons advocated that surgical field block was an effective intervention with no/minimal complication risk. There is very little literature critically evaluating efficacy of these perioperative management strategies for PAO.

Conclusion

There is significant practice variability in peri-operative management of PAO surgery. We report various strategies utilized by a group of experienced surgeons and review supporting literature. There are significant knowledge gaps in best surgical pain management strategies, adjunct medications, surgical field blocks, and use of CPM that need further investigation. Level of Evidence: IV.

The Relationship Between Postoperative Patient-Reported Psychological Outcomes and Preoperative Pain Characteristics in Patients Who Underwent Periacetabular Osteotomy

This study sought to investigate the relationship between multiple preoperative characteristics of pain (maximum pain severity location, the presence of pain in certain locations, the highest level of pain, and the number of pain locations) and psychological outcome measures as reported by patients. Fifty-four hips (50 patients) that underwent periacetabular osteotomy to treat acetabular dysplasia between February 2017 and July 2020 were reviewed using the Depression, Anxiety, and Stress Scale-21 (DASS21), Hospital Anxiety and Depression Scale (HADS), and Pain Catastrophizing Scale (PCS), radiographic analysis, and questionnaires concerning pain severity/location. Twenty-six hips had their worst pain in the groin, whereas 28 hips had greater or equal levels of pain at another location. There was no significant difference between these two locations on any of the postoperative psychological outcomes (HADS, P=.53; DASS21, P=.85; PCS, P=.97). Additionally, there was not a significant relationship between pain in any location other than the groin and any postoperative psychological outcomes (P≥.08). Finally, the highest level of preoperative pain and the number of locations of pain demonstrated no significant relationship with postoperative psychological outcomes (maximum severity: HADS, P=.28; DASS21, P=.49; PCS, P=.57; number of pain locations: HADS, P=.47; DASS21, P=.60; PCS, P=.35). Variance in preoperative pain location, severity, and number of pain locations seemingly does not result in any significant effect on postoperative psychological outcomes. Thus, a large range of patients with acetabular dysplasia may experience similar, favorable psychological outcomes from treatment with periacetabular osteotomy notwithstanding the characteristics of preoperative pain. [Orthopedics. 2024;47(1):28-33.].

Pain, function and quality of life are impaired in adults undergoing periacetabular osteotomy (PAO) for hip dysplasia: a systematic review and meta-analysis

BACKGROUND

Hip dysplasia is a common condition in active adults with hip pain that can lead to joint degeneration. Periacetabular osteotomy (PAO) is a common surgical treatment for hip dysplasia. The effect of this surgery on pain, function and quality of life (QOL) has not been systematically analysed.

PURPOSE

In adults with hip dysplasia: (1) evaluate differences in pain, function and QOL in those undergoing PAO and healthy controls; (2) evaluate pre- to post-PAO changes in pain, function and QOL; (3) evaluate differences in pain, function and QOL in those with mild versus severe dysplasia, undergoing PAO; and (4) evaluate differences in pain, function and QOL in those having primary PAO versus those with previous hip arthroscopy.

METHODS

A comprehensive, reproducible search strategy was performed on 5 different databases. We included studies that assessed pain, function and QOL in adults undergoing PAO for hip dysplasia, using hip-specific patient reported outcomes measures.

RESULTS

From 5017 titles and abstracts screened, 62 studies were included. Meta-analysis showed PAO patients had worse outcomes pre- and post-PAO compared to healthy participants. Specifically, pain (standardised mean difference [SMD] 95% confidence interval [CI]): -4.05; -4.78 to -3.32), function (-2.81; -3.89 to -1.74), and QOL (-4.10; -4.43 to -3.77) were significantly poorer preoperatively.Meta-analysis found patients experienced improvements following PAO. Pain improved from pre-surgery to 1-year (standardised paired difference [SPD] 1.35; 95% CI, 1.02-1.67) and 2 years postoperatively (1.35; 1.16-1.54). For function, the activities of daily living scores at 1 year (1.22; 1.09-1.35) and 2 years (1.06; 0.9-1.22) and QOL at 1 year (1.36; 1.22-1.5) and 2 years (1.3; 1.1-1.5) all improved. No difference was found between patients undergoing PAO with mild versus severe dysplasia.

CONCLUSIONS

Before undergoing PAO surgery, adults with hip dysplasia have worse levels of pain, function and QOL compared to healthy participants. These levels improve following PAO, but do not reach the same level as their healthy participants.

REGISTRATION

PROSPERO (CRD42020144748).

Analysis of survivorship following periacetabular osteotomy for hip dysplasia based on three-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.

The Relationship Between Pelvic Tilt and Clinical Outcomes After Hip Preservation Surgery in Femoroacetabular Impingement Syndrome and Hip Dysplasia

Pelvic tilt is thought to be a compensatory mechanism in hip pathology, specifically in patients with femoroacetabular impingement syndrome (FAIS) and hip dysplasia. This study investigated the relationship between preoperative pelvic tilt and postoperative outcomes in patients undergoing hip preservation surgery for FAIS or hip dysplasia. We reviewed a prospective hip preservation database for demographic, radiographic, and outcome data for 89 patients who underwent hip preservation surgery with a primary diagnosis of FAIS or dysplasia from 2016 to 2020. Pelvic tilt was assessed on the standing anteroposterior radiograph with the pubic symphysis to sacroiliac joint (PS-SI) distance measurement. The International Hip Outcome Tool 12 (iHOT-12), Hip Outcome Score, Harris Hip Score, UCLA activity score, and European Quality of Life-Visual Analog Scale were used to assess hip function and pain preoperatively and postoperatively. The mean pelvic tilt (PS-SI distance) was 86.4±18.3 mm for the FAIS group and 96.2±15.1 mm for the dysplasia group. The statistical analysis demonstrated a positive relationship between pelvic tilt and change in iHOT-12 score (rs=0.262, P=.019) for all 89 patients with hip pathology and, separately, a trend toward significance for the 42 patients with FAIS (rs=0.330, P=.056). No other significant relationships were observed. The improvement in iHOT-12 score was greater for patients with more anterior tilt and less for patients with posterior pelvic tilt, regardless of underlying hip etiology. These results provide intriguing insights into an initial investigation on pelvic tilt in patients undergoing hip preservation surgery. Further investigation is necessary to assess pelvic tilt preoperatively and postoperatively, spinal parameters, and longer-term outcomes. [Orthopedics. 2023;46(6):e341-e346.].

Duration of Symptoms Does Not Significantly Influence Short-term Outcomes for Patients Undergoing Periacetabular Osteotomy

Factors influencing the clinical outcomes after periacetabular osteotomy (PAO) have not been well explored. This study evaluated the influence of symptom duration in developmental dysplasia of the hip on short-term patient-reported outcomes after PAO. A retrospective review of prospectively collected data identified PAOs performed on 139 patients. Sixty-five patients were then stratified into two groups based on preoperative symptom duration: 2 years or less (n=22) vs more than 2 years (n=43). We compared the results of hip-specific patient-reported outcome surveys collected preoperatively and postoperatively. When comparing the two groups, we found no significant differences in clinical outcome scores except for the UCLA Activity Scale. The shorter duration group achieved improvement 6 months postoperatively on the visual analog scale average pain score (from 4.5 to 2.167; P=.0017), International Hip Outcome Tool-12 (from 42.95 to 59.19; P=.0176), and Harris Hip Score (from 53.88 to 69.88; P=.049). The longer duration group also achieved postoperative improvement across multiple surveys. Nevertheless, a multivariate analysis controlling for age, sex, and body mass index and found that symptom duration did not independently affect the change in clinical outcomes. Although PAO leads to improvements in functional status and pain, preoperative symptom duration does not significantly affect these clinical outcomes. [Orthopedics. 2023;46(6):365-372.].

Psychological status affects postoperative quality of life, function, and pain after periacetabular osteotomy

Aims

Psychological status may be an important predictor of outcome after periacetabular osteotomy (PAO). The aim of this study was to investigate the influence of psychological distress on postoperative health-related quality of life, joint function, self-assessed pain, and sports ability in patients undergoing PAO.

Methods

In all, 202 consecutive patients who underwent PAO for developmental dysplasia of the hip (DDH) at our institution from 2015 to 2017 were included and followed up at 63 months (SD 10) postoperatively. Of these, 101 with complete data sets entered final analysis. Patients were assessed by questionnaire. Psychological status was measured by Brief Symptom Inventory (BSI-18), health-related quality of life was raised with 36-Item Short Form Survey (SF-36), hip functionality was measured by the short version 0f the International Hip Outcome Tool (iHOT-12), Subjective Hip Value (SHV), and Hip Disability and Outcome Score (HOS). Surgery satisfaction and pain were assessed. Dependent variables (endpoints) were postoperative quality of life (SF-36, HOS quality of life (QoL)), joint function (iHOT-12, SHV, HOS), patient satisfaction, and pain. Psychological distress was assessed by the Global Severity Index (GSI), somatization (BSI Soma), depression (BSI Depr), and anxiety (BSI Anx). Influence of psychological status was assessed by means of univariate and multiple multivariate regression analysis.

Results

In multiple multivariate regression, postoperative GSI, BSI Soma, and BSI Depr had a negative effect on postoperative SF-36 (e -2.07, -3.05, and -2.67, respectively; p < 0.001), iHOT-12 (e -1.35 and -4.65, respectively; p < 0.001), SHV (e -1.20 and -2.71, respectively; p < 0.001), HOS QoL (e -2.09 and -4.79, respectively; p < 0.001), HOS Function (e -1.00 and -3.94, respectively; p < 0.001), and HOS Sport (e -1.44 and -5.29, respectively; p < 0.001), and had an effect on postoperative pain (e 0.13 and 0.37, respectively; p < 0.001).

Conclusion

Psychological distress, depression, and somatization disorders affect health-related quality of life, perceived joint function, and sports ability. Pain perception is significantly increased by somatization. However, patient satisfaction with surgery is not affected.

Relationships between self-perceived and clinical expression of pain and function differ based on the underlying pathology of the human hip

BACKGROUND

Patient-reported outcomes are commonly used to assess patient symptoms. The effect of specific hip pathology on relationships between perceived and objectively measured symptoms remains unclear. The purpose of this study was to evaluate differences of function and pain in patients with FAIS and DDH, to assess the correlation between perceived and objective function, and to determine the influence of pain on measures of function.

METHODS

This prospective cross-sectional study included 35 pre-operative patients (60% female) with femoroacetabular impingement syndrome (FAIS) and 37 pre-operative patients (92% female) with developmental dysplasia of the hip (DDH). Objectively measured function (6-min walk [6MWT], single leg hop [SLHT], Biodex sway [BST], hip abduction strength [HABST], and STAR excursion balance reach [STAR] tests), patient-reported function (UCLA Activity, Hip Outcome Score [HOS], Short Form 12 [SF-12], and Hip Disability and Osteoarthritis Outcome Score [HOOS]), and patient-reported pain (HOOS Pain, visual analogue scale (VAS), and a pain location scale) were collected during a pre-surgical clinic visit. Between-group comparisons of patient scores were performed using Wilcoxon Rank-Sum tests. Within-group correlations were analyzed using Spearman's rank correlation coefficients. Statistical correlation strength was defined as low (r =  ± 0.1-0.3), moderate (r =  ± 0.3-0.5) and strong (r >  ± 0.5).

RESULTS

Patients with DDH reported greater pain and lower function compared to patients with FAIS. 6MWT distance was moderately-to-strongly correlated with a number of patient-reported measures of function (FAIS: r = 0.37 to 0.62, DDH: r = 0.36 to 0.55). Additionally, in patients with DDH, SLHT distance was well correlated with patient reported function (r = 0.37 to 0.60). Correlations between patient-reported pain and objectively measured function were sparse in both patient groups. In patients with FAIS, only 6MWT distance and HOOS Pain (r = -0.53) were significantly correlated. In patients with DDH, 6MWT distance was significantly correlated with VAS Average (r = -0.52) and Best (r = -0.53) pain.

CONCLUSION

Pain is greater and function is lower in patients with DDH compared to patients with FAIS. Moreover, the relationship between pain and function differs between patient groups. Understanding these differences is valuable for informing treatment decisions. We recommend these insights be incorporated within the clinical continuum of care, particularly during evaluation and selection of surgical and therapeutic interventions.

Periacetabular Osteotomy for Symptomatic Acetabular Dysplasia in Patients ≥40 Years Old: Intermediate and Long-Term Outcomes and Predictors of Failure

BACKGROUND

The Bernese periacetabular osteotomy (PAO) is controversial as a treatment for symptomatic acetabular dysplasia in patients ≥40 years of age. We conducted a retrospective study to evaluate the outcomes, measure the survival rate, and identify factors associated with PAO failure in patients ≥40 years of age.

METHODS

We performed a retrospective study of patients ≥40 years of age undergoing PAO. Study eligibility criteria were met by 166 patients (149 women; mean age, 44 ± 3 years), and 145 (87%) were followed for ≥4 years after PAO. We used a Kaplan-Meier curve with right-censoring to calculate survivorship, with "failure" defined as either conversion to or recommendation for total hip arthroplasty or a Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score of ≥10 at the most recent follow-up. We used simple logistic regression models to determine whether any preoperative characteristics were significantly associated with PAO failure.

RESULTS

The median follow-up time was 9.6 years (range, 4.2 to 22.5 years). Sixty-one of 145 hips (42%, 95% confidence interval [CI] = 34% to 51%) experienced PAO failure during follow-up. The median survival time was 15.5 years (95% CI = 13.4 to 22.1 years). The median survival time was longer for hips with no or mild preoperative osteoarthritis: 17.0 years for Tönnis grade 0, 14.6 years for grade 1, and 12.9 years for grade 2. Higher preoperative Tönnis arthritis grades (p = 0.03) and worse WOMAC function scores (p < 0.001) were associated with an increased likelihood of failure.

CONCLUSIONS

PAO is usually effective at improving function and is effective at preserving the hip in patients ≥40 years of age provided that they have good preoperative function and no or mild preoperative osteoarthritis (Tönnis grade 0 or 1). Patients who are ≥40 years old with advanced preoperative osteoarthritis (Tönnis grade 2) and those with poor preoperative dysfunction have a high risk of therapeutic failure after PAO.

LEVEL OF EVIDENCE

Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Joint awareness following periacetabular osteotomy in patients with hip dysplasia

Aims

The aims of this study were to validate the Forgotten Joint Score-12 (FJS-12) in the postoperative evaluation of periacetabular osteotomy (PAO), identify factors associated with joint awareness after PAO, and determine the FJS-12 threshold for patient-acceptable symptom state (PASS).

Methods

Data from 686 patients (882 hips) with hip dysplasia who underwent transposition osteotomy of the acetabulum, a type of PAO, between 1998 and 2019 were reviewed. After screening the study included 442 patients (582 hips; response rate, 78%). Patients who completed a study questionnaire consisting of the visual analogue scale (VAS) for pain and satisfaction, FJS-12, and Hip disability and Osteoarthritis Outcome Score (HOOS) were included. The ceiling effects, internal consistency, convergent validity, and PASS thresholds of FJS-12 were investigated.

Results

The median follow-up was 12 years (interquartile range 7 to 16). The ceiling effect of FJS-12 was 7.2%, the lowest of all the measures examined. FJS-12 correlated with all HOOS subscales (ρ = 0.72 to 0.77, p < 0.001) and pain and satisfaction-VAS (ρ = -0.63 and 0.56, p < 0.001), suggesting good convergent validity. Cronbach's α was 0.95 for the FJS-12, which indicated excellent internal consistency. The median FJS-12 score for preoperative Tönnis grade 0 hips (60 points) was higher than that for grade 1 (51 points) or 2 (46 points). When PASS was defined as pain-VAS < 21 and satisfaction-VAS ≥ 77, the FJS-12 threshold that maximized the sensitivity and specificity for detecting PASS was 50 points (area under the curve (AUC) = 0.85).

Conclusion

Our results suggest that FJS-12 is a valid and reliable assessment tool for patients undergoing PAO, and the threshold of 50 points may be useful to determine patient satisfaction following PAO in clinical settings. Further investigation of the factors influencing postoperative joint awareness may enable improved prediction of treatment efficacy and informed decision-making regarding the indication of PAO.

Periacetabular osteotomy with intraoperative computer-assisted modalities: a systematic review

The role of intraoperative computer-assisted modalities for periacetabular osteotomy (PAO), as well as the perioperative and post-operative outcomes for these techniques, remains poorly defined. The purpose of this systematic review was to evaluate the techniques and outcomes of intraoperative computer-assisted modalities for PAO. Three databases (PubMed, CINAHL/EBSCOHost and Cochrane) were searched for clinical studies reporting on computer-assisted modalities for PAO. Exclusion criteria included small case series (<10 patients), non-English language and studies that did not provide a description of the computer-assisted technique. Data extraction included computer-assisted modalities utilized, surgical techniques, demographics, radiographic findings, perioperative outcomes, patient-reported outcomes (PROs), complications and subsequent surgeries. Nine studies met the inclusion criteria, consisting of 208 patients with average ages ranging from 26 to 38 years. Intraoperative navigation was utilized in seven studies, patient-specific guides in one study and both modalities in one study. Three studies reported significantly less intraoperative radiation exposure (P < 0.01) in computer-assisted versus conventional PAOs. Similar surgical times and estimated blood loss (P > 0.05) were commonly observed between the computer-assisted and conventional groups. The average post-operative lateral center edge angles in patients undergoing computer-assisted PAOs ranged from 27.8° to 37.4°, with six studies reporting similar values (P > 0.05) compared to conventional PAOs. Improved PROs were observed in all six studies that reported preoperative and post-operative values of patients undergoing computer-assisted PAOs. Computer-assisted modalities for PAO include navigated tracking of the free acetabular fragment and surgical instruments, as well as patient-specific cutting guides and rotating templates. Compared to conventional techniques, decreased intraoperative radiation exposure and similar operative lengths were observed with computer-assisted PAOs, although these results should be interpreted with caution due to heterogeneous operative techniques and surgical settings.

Incidence and risk factors for non-union of the superior ramus osteotomy when hip dysplasia is treated with periacetabular osteotomy

Periacetabular osteotomy (PAO) is a well-established surgical treatment for hip dysplasia. Few studies report risk factors for the development of superior ramus osteotomy non-union. The purpose of this investigation was to document the incidence and risk factors for this complication. We identified 316 consecutive hips that underwent PAO for symptomatic acetabular dysplasia with a minimum 1-year radiographic follow-up. We developed and validated a technique to measure the superior ramus osteotomy location on anterior-posterior (AP) pelvis radiographs and computed tomography. Logistic regression with generalized estimating equations was used to evaluate the relationships between odds of non-union and potential demographic and radiographic predictor variables in univariate and multivariate analyses. Twenty-nine (9.2%) hips developed superior ramus non-union. Age {median [interquartile range (IQR)] 23 years (18-35) healed versus 35 years (26-40) non-united, P = 0.001}, pre-operative lateral center-edge angle (LCEA) [16° (11-20) healed versus 10° (6-13) non-united, P < 0.001] and the distance from the superior ramus osteotomy to the ilioishial line [15.8 mm (13.2-18.7) healed versus 18.1 mm (16.2-20.5) non-united, P < 0.001] varied significantly between groups. Using multivariate analysis, moderate-to-severe dysplasia [LCEA < 15°, odds ratio (OR) 5.95, standard error (SE) 3.32, 95% confidence interval (CI) 1.99-17.79, P = 0.001], increased age (5-year increase, OR 1.29, SE 3.32, 95% CI 1.105-1.60, P-value = 0.018) and distance from the ilioishial line (3-mm increase, OR 1.67, SE 0.22, 95% CI 1.29-2.18, P < 0.001) were at increased risk of developing non-union. Superior ramus osteotomy non-union is common after PAO. Older age, moderate-to-severe dysplasia, and more medial osteotomy location were independent risk factors for non-union. Consideration should be made in high-risk patients for a more lateral superior ramus osteotomy and adjuvant medical and surgical interventions.

Clinical results of periacetabular osteotomy with structural bone allograft for the treatment of severe hip dysplasia

Aims

To clarify the mid-term results of transposition osteotomy of the acetabulum (TOA), a type of spherical periacetabular osteotomy, combined with structural allograft bone grafting for severe hip dysplasia.

Methods

We reviewed patients with severe hip dysplasia, defined as Severin IVb or V (lateral centre-edge angle (LCEA) < 0°), who underwent TOA with a structural bone allograft between 1998 and 2019. A medical chart review was conducted to extract demographic data, complications related to the osteotomy, and modified Harris Hip Score (mHHS). Radiological parameters of hip dysplasia were measured on pre- and postoperative radiographs. The cumulative probability of TOA failure (progression to Tönnis grade 3 or conversion to total hip arthroplasty) was estimated using the Kaplan-Meier product-limited method, and a multivariate Cox proportional hazard model was used to identify predictors for failure.

Results

A total of 64 patients (76 hips) were included in this study. The median follow-up period was ten years (interquartile range (IQR) five to 14). The median mHHS improved from 67 (IQR 56 to 80) preoperatively to 96 (IQR 85 to 97) at the latest follow-up (p < 0.001). The radiological parameters improved postoperatively (p < 0.001), with the resulting parameters falling within the normal range in 42% to 95% of hips. The survival rate was 95% at ten years and 80% at 15 years. Preoperative Tönnis grade 2 was an independent risk factor for TOA failure.

Conclusion

Our findings suggest that TOA with structural bone allografting is a viable surgical option for correcting severely dysplastic acetabulum in adolescents and young adults without advanced osteoarthritis, with favourable mid-term outcomes.

Mechanical influence of periacetabular osteotomy on late total hip arthroplasty

Periacetabular osteotomy (PAO) is an effective technique to treat symptomatic hip dysplasia. However, following PAO, some patients still experience persistent pain or development of hip arthritis, requiring total hip arthroplasty (THA). Issues such as whether patients with PAO are necessarily at increased risk of post-THA complications and revision of the prosthesis remain debatable. The purpose of this study was to evaluate the biomechanical influence of PAO on the acetabulum after THA by finite element analysis. Eight patients with developmental dysplasia of the hip (DDH) diagnosed in the Fourth Medical Center of the PLA General Hospital were enrolled in this research. Patient-specific hip joint models were reconstructed from computed tomography scans, and the hip prosthesises, were established via computer-aided design (CAD) modeling technology. The finite element analysis was conducted to compare the surface and internal stress through the process mapping of the model due to the THA. Compared with the THA after PAO, the position of the high-stress area of the acetabular fossa of patients without PAO decreased, and the high-stress area developed toward the lower edge of the acetabulum. Although the high-stress area of the suprapubic branch did not change significantly, the peak stress was higher (t = .00237). The analysis of the section plane showed that the high-stress area of cancellous bone had a large distribution. The acetabular size and vertical distance of rotation center (VDRC) were significantly correlated with the maximum postoperative acetabular equivalent stress (p = .011, p = .001). In the Post group, both the horizontal distance of rotation center (HDRC) and A-ASA were significantly correlated with postoperative maximal acetabular equivalent stress, with a significance of 0.014 and 0.035, respectively. The risk of postoperative prosthetic revision following THA is not increased by PAO, although the risk of postoperative suprapubic branch fracture is increased.

Effects of different pelvic osteotomies on acetabular morphology in developmental dysplasia of hip in children

Developmental dysplasia of hip seriously affects the health of children, and pelvic osteotomy is an important part of surgical treatment. Improving the shape of the acetabulum, preventing or delaying the progression of osteoarthritis is the ultimate goal of pelvic osteotomies. Re-directional osteotomies, reshaping osteotomies and salvage osteotomies are the three most common types of pelvic osteotomy. The influence of different pelvic osteotomy on acetabular morphology is different, and the acetabular morphology after osteotomy is closely related to the prognosis of the patients. But there lacks comparison of acetabular morphology between different pelvic osteotomies, on the basis of retrospective analysis and measurable imaging indicators, this study predicted the acetabular shape after developmental dysplasia of the hip pelvic osteotomy in order to help clinicians make reasonable and correct decisions and improve the planning and performance of pelvic osteotomy.

Dysplastic hips demonstrate increased joint translation at higher body mass index

OBJECTIVE

To determine which radiographic measures used to define the severity of hip dysplasia are associated with hip joint translation and to investigate relationships between position, body mass index, and joint translation.

MATERIALS AND METHODS

This is a cross-sectional retrospective study evaluating 10 validated radiographic measures of dysplasia on weight-bearing AP pelvis and supine 45-degree bilateral Dunn radiographs of 93 young adults with symptomatic hip dysplasia presenting to a single academic institution between October 2016 and May 2019. We determined the difference between standing and supine measurements for each hip and the correlation of each measure with the patient's body mass index.

RESULTS

Femoral head extrusion index was 2.49% lower on supine X-ray (p = 0.0020). Patients with higher body mass index had higher center gap distance (p = 0.0274), femoral head extrusion (p = 0.0170), and femoral head lateralization (p = 0.0028) when standing. They also had higher Tönnis angle (p_standing = 0.0076, p_supine = 0.0121) and lower lateral center-edge angle (p_standing = 0.0196, p_supine = 0.0410) in both positions. The difference in femoral head lateralization between standing and supine positions increased with higher body mass index (p = 0.0081).

CONCLUSION

Translation of the hip joint with position change is demonstrated by decreased femoral head extrusion index on supine X-ray. Patients with higher body mass index had more dysplastic hips, as measured by five of six radiographic outcomes of dysplasia, and experienced more translation with weight-bearing, reflected by increased femoral head lateralization.

Patient-Reported Outcomes and Factors Impacting Success of the Periacetabular Osteotomy

Hip dysplasia is a condition affecting both infants and adults, characterized by a shallow acetabulum that does not sufficiently cover the head of the femur. This leads to instability of the hip and elevated levels of mechanical stress around the acetabular rim. A popular procedure for the correction of hip dysplasia is the periacetabular osteotomy (PAO), in which fluoroscopically guided osteotomies around the pelvis are made to allow for repositioning of the acetabulum to fit properly on the femoral head. This systematic review aims to analyze patient factors that impact outcomes, as well as patient-reported outcomes such as the Harris Hip Score (HHS) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC). The patients in this review did not undergo any prior intervention for acetabular hip dysplasia, allowing for an unbiased reporting of outcomes from all included studies. Of studies reporting HHS, the mean preoperative HHS was 68.92 and the mean postoperative HHS was 89.1. Of the study that reported mHHS, the mean preoperative mHHS was 70, and the mean postoperative mHHS was 91. Of the studies reporting WOMAC, the mean preoperative WOMAC was 66, and the mean postoperative WOMAC was 63. Key findings of this review are that of the seven included studies, six achieved a minimally important clinical difference (MCID) based on patient-reported outcomes, and factors impacting outcome are preoperative Tönnis osteoarthritis (OA) grade, pre and postoperative lateral-center edge angle (LCEA), preoperative hip joint congruency, postoperative Tönnis angle, and age. In patients with no prior intervention for hip dysplasia, the PAO is a successful procedure with significant improvement in postoperative patient-reported outcomes. Despite the reported success of the PAO, proper patient selection is vital to avoid early conversions to total hip arthroplasty (THA) and prolonged pain. However, further investigation is prompted regarding the long-term survivorship of the PAO in patients with no prior intervention for hip dysplasia.

[Complication management after periacetabular osteotomy]

BACKGROUND

Hip dysplasia is the most common cause of secondary hip osteoarthritis. The Ganz periacetabular osteotomy (PAO) is a well-established procedure that allows a reliable and reproducible correction of the complex pathology. The promising medium and long-term good treatment results are offset by the potential risk of complications from an invasive pelvic procedure. Considering the mainly young age of the patients, knowledge of the possible complications and the resulting adequate therapy is crucial.

TREATMENT DEVELOPMENT

The continuous development of surgical techniques and increase in overall surgical experience alongside the appreciation of critical surgical steps have led to a substantial reduction of serious complications. In addition, to improve patient outcome, a greater understanding of the associated pathologies that may be related to hip dysplasia is essential.

The Effects of Arthroscopic Labral Repair on Patient-Reported Outcomes in the Setting of Periacetabular Osteotomy

BACKGROUND

It is currently unknown whether the addition of arthroscopic labral repair in the setting of periacetabular osteotomy (PAO) provides any clinical benefit.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare outcomes of patients who underwent arthroscopic labral repair concomitantly with PAO versus patients who underwent PAO alone. We hypothesized that there would be no difference in patient-reported outcome measures (PROMs) between the cohorts.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients undergoing PAO from a single-center prospective hip preservation registry were eligible for this study if they completed pre- and postoperative PROMs (minimum, 1 year). PROMs were collected at 1 year, 2 years, and latest follow-up at 6.05 years for PAO group and 4.2 years for scope/PAO group. The study group consisted of 53 patients who underwent arthroscopic labral repair at the time of their PAO, and the comparison group consisted of 170 patients who underwent PAO alone. A subset of the PAO group who had radiologic evidence of a detached labral tear (n = 33) was also compared with the rest of the PAO-alone group. PROMs were compared at every time point for both groups as well as the subset of patients who underwent PAO alone despite a labral tear.

RESULTS

The mean follow-up of all patients was 2 years (range, 1-6 years). Overall, 85.2% of the PAO group and 85.7% of the scope/PAO group met the minimal clinically important difference for either the modified Harris Hip Score (mHHS) or the International Hip Outcome Tool (iHOT-33) at the most recent follow-up. There was no difference in improvement between groups (mHHS, P = .670; iHOT-33, P = .944). Patients who had a radiologically diagnosed detached labral tear and underwent PAO alone had no difference in outcomes when compared with the rest of the PAO cohort (mHHS, P = .981; iHOT-33, P = .909).

CONCLUSION

There was no significant benefit measured by PROMs at follow-up for concomitant arthroscopic labral repair in the setting of PAO.

[Hip dysplasia: What influence do age, arthrosis and concomitant diseases have on the treatment result?]

Pelvic osteotomies are an established treatment for symptomatic adult hip dysplasia with a promising long-term outcome. Results depend not only on the achieved acetabular reorientation but also on patient-factors like preoperative joint condition (degree of osteoarthritis and joint congruency) and age. Additionally, the diagnosis and appropriate therapy of impingement-associated hip deformities is essential in order to achieve good mid- and long-term outcomes. The influence of chondrolabral pathology on the outcome of pelvic osteotomies is not yet defined. Symptomatic patients with residual dysplasia after previous pelvic or acetabular osteotomies can benefit from an additional osteotomy, although results can be worse in comparison to prior unoperated joints. Obesity can make surgery more demanding and increases the complication profile of PAO, although it has no influence on the postoperative outcome. Regarding the overall prognosis after an osteotomy, the consideration of combined risk factors is superior to the concentration on individual factors alone.

Risk of acute myocardial infarction, stroke, and venous thromboembolism among patients with anti-neutrophil cytoplasmic antibody-associated vasculitis in South Korea: A nationwide population-based study

OBJECTIVES

To investigate the incidence and risk of cerebro-cardiovascular comorbidities (stroke, acute myocardial infarction, venous thromboembolism, and pulmonary embolism) in anti-neutrophil cytoplasmic antibody-associated vasculitis using nationwide Korean population-based medical claims data.

METHODS

We identified 1905 patients with newly diagnosed anti-neutrophil cytoplasmic antibody-associated vasculitis during 2009-2019. Incidence rates and hazard ratios with 95% confidence intervals were calculated to estimate the risk of cerebro-cardiovascular comorbidities in these patients and compared to age- and sex-matched controls (1:10) using the Cox proportional hazards model.

RESULTS

Most patients had microscopic polyangiitis (42.5%), followed by granulomatosis with polyangiitis (29.1%) and eosinophilic granulomatosis with polyangiitis (28.4%). The annual incidence rate of anti-neutrophil cytoplasmic antibody-associated vasculitis in 2019 was 0.55 per 100,000 person-years. Cerebro-cardiovascular comorbidities occurred in 12.6%. Stroke was most common (64.6%), followed by venous thromboembolism (34.6%), pulmonary embolism (18.3%), and acute myocardial infarction (5.4%). Korean patients with anti-neutrophil cytoplasmic antibody-associated vasculitis were at a significantly (2.3 times) higher overall risk for cerebro-cardiovascular comorbidities than the general population (adjusted hazard ratios, 4.5, 3.1, and 2.0 times higher for pulmonary embolism, venous thromboembolism, and stroke, respectively). These findings were similar for patients with each subtype of anti-neutrophil cytoplasmic antibody-associated vasculitis.

CONCLUSIONS

This is the first nationwide population-based study to demonstrate a significant risk of cerebro-cardiovascular comorbidities as complications of anti-neutrophil cytoplasmic antibody-associated vasculitis in Korean patients. Knowing these risks may enable personalized patient care and improve overall survival.

Survival of the dysplastic hip after periacetabular osteotomy: a meta-analysis

BACKGROUND

Periacetabular osteotomy (PAO) has become a popular procedure for re-orientation of the acetabulum in patients with a developmental pathomorphology. Since its first description by Reinhold Ganz in 1988, many institutions worldwide have adopted the procedure for the treatment of developmental hip dysplasia (DDH) and have subsequently reported their results. The aim of this study was to provide a meta-analysis of the likelihood of long-term survival of a dysplastic hip after PAO.

METHODS

A systematic literature review was conducted using Medline, Cochrane and "Web of Science" databases to identify articles reporting survival estimates for PAO in patients with DDH. To be included in the analysis, studies had to include patient cohorts aged <40 years, with Osteoarthritis grade < Tönnis III and no form of neuromuscular dysplasia. Adjustment for cohort overlap was performed. Quality assessment included level of evidence (LOE) according to the oxford center for LOE criteria and the "Methodological index for non-randomized studies (MINORS)". After data extraction, a random-effects meta-analytical model was applied to provide weighted mean estimates of survival at 5 years, 10 years, 15 years and 20 years.

RESULTS

Nine relevant articles included 2268 dysplastic hips that underwent PAO in 9 institutions. Of the included studies, 5 presented level III evidence and 4 presented level IV evidence. The MINORS score was 11 for 3 studies, 12 for 4 studies and 13 for 2 studies. The 5-year survival after PAO was 96.1% (95% CI, 94.9-97.3), the 10-year survival was 91.3% (95% CI, 87.7-94.8), 15-year survival 85.0% (95% CI, 78.9-91.1), 20-year survival 67.6% (95% CI, 53.9-81.3).

CONCLUSIONS

The results provide a representative survival estimate of a dysplastic hip after PAO based on global evidence. This should provide clinicians and patients with an adequate reflection of prognostic expectations after this kind of surgery.

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

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

Outcomes of Periacetabular Osteotomy for Borderline Acetabular Dysplasia

BACKGROUND

The optimal surgical treatment (hip arthroscopy compared with periacetabular osteotomy [PAO]) for borderline acetabular dysplasia (lateral center-edge angle [LCEA], 18° to 25°) remains a topic of debate. To date, the literature has focused primarily on arthroscopy outcomes, with only a few small reports on PAO outcomes. The purpose of this study was to define PAO outcomes in a large cohort of borderline hips. In a secondary analysis, we assessed the effect of prior failed arthroscopy, concurrent hip arthroscopy, and concurrent femoral osteoplasty on PAO outcomes in this cohort.

METHODS

A prospective database was retrospectively reviewed for patients who underwent PAO for symptomatic instability in the setting of borderline dysplasia (LCEA, 18° to 25°). Of the 232 identified hips, 186 (80.2%) were assessed at a mean follow-up of 3.3 ± 2.0 years postoperatively. The mean patient age was 25.2 ± 8.5 years (range, 14 to 45 years), and 88.2% were female. Thirty hips (16.1%) had undergone a failed prior arthroscopy. Arthroscopy was performed concurrently with the PAO in 130 hips (69.9%), and femoral osteoplasty was performed concurrently in 120 hips (64.5%). The modified Harris hip score (mHHS) was assessed relative to the minimal clinically important difference (MCID) of 8 and patient acceptable symptom state (PASS) of 74. Clinical failure was defined as a reoperation for persistent symptoms or a failure to achieve either the mHHS MCID or PASS.

RESULTS

Of the 156 hips undergoing a primary surgical procedure, clinical success was achieved in 148 hips (94.9% [95% confidence interval (CI), 90.2% to 97.4%]). Two hips (1.3% [95% CI, 0.4% to 4.6%]) underwent reoperation (hip arthroscopy) for persistent symptoms and an additional 6 hips (3.8% [95% CI, 1.8% to 8.1%]) failed to achieve the mHHS MCID or PASS, for a clinical failure rate of 5.1% (95% CI, 2.6% to 9.8%); 8.8% reported dissatisfaction with the surgical procedure. Clinical failure was more frequent among the 30 hips (23.3% [95% CI, 11.8% to 40.9%]; p = 0.001) that had undergone a prior failed arthroscopy. There were no outcome differences between hips that had or had not undergone concurrent hip arthroscopy or femoral osteoplasty.

CONCLUSIONS

This study demonstrates excellent early outcomes of PAO for borderline acetabular dysplasia, with significant clinical improvement in 94.9% of patients undergoing a primary surgical procedure; 91.2% were satisfied with the surgical procedure.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Clinical Outcomes for Total Hip Arthroplasty with and without Previous Curved Periacetabular Osteotomy

There are currently no reports on the clinical outcomes after total hip arthroplasty (THA) with previous curved periacetabular osteotomy (CPO), although the outcomes after THA with non-CPO types of periacetabular osteotomy have been reported. This study aimed to clarify the differences in clinical outcomes and radiographic features after THA with or without previous CPO. We performed a retrospective case-control with individual matching study. The participants were 10 patients with 11 hips that underwent cementless THA between October 1998 and October 2018 with previous CPO (osteotomy group). For the control group, we matched age, sex, and follow-up period, and included 32 patients with 33 hips that underwent cementless THA without previous CPO at a 1:3 ratio. The Harris Hip Score (HHS), cup size, position, and alignment, global offset (GO), operative time, perioperative blood loss, frequency of osteophyte removal, and major complications were compared between the two groups. The osteotomy group had no cases with revision surgery and dislocation. No significant differences were found between the two groups as follows: mean HHS, 94.9 points in the osteotomy group versus 92.7 points in the control group at the final follow-up; mean GO, 70.1 mm in the osteotomy group versus 71.4 mm in the control group; cup size, position, and alignment after THA; operative time; and perioperative blood loss. The frequency of osteophyte removal was higher in the osteotomy group. The take-home messages were that the clinical outcomes, including HHS, and radiographic features, including GO, after THA were equivalent in the two groups.

Combined femoral and acetabular version is sex-related and differs between patients with hip dysplasia and acetabular retroversion

AIMS

Frequency of abnormal femoral and acetabular version (AV) and combinations are unclear in patients with developmental dysplasia of the hip (DDH). This study aimed to investigate femoral version (FV), the proportion of increased FV and femoral retroversion, and combined-version (CV, FV+AV) in DDH patients and acetabular-retroversion (AR).

PATIENTS AND METHODS

A retrospective IRB-approved observational study was performed with 78 symptomatic DDH patients (90 hips) and 65 patients with femoroacetabular-impingement (FAI) due to AR (77 hips, diagnosis on AP radiographs). CT/MRI-based measurement of FV (Murphy method) and central AV were compared. Frequency of increased FV(FV > 25°), severely increased FV (FV > 35°) and excessive FV (FV > 45°) and of decreased FV (FV < 10°) and CV (McKibbin-index/COTAV-index) was analysed.

RESULTS

Mean FV and CV was significantly (p < 0.001) increased of DDH patients (mean ± SD of 25 ± 11° and 47 ± 18°) compared to AR (16 ± 11° and 28 ± 13°). Mean FV of female DDH patients (27 ± 16°) and AR (19 ± 12°) was significantly (p < 0.001) increased compared to male DDH patients (18 ± 13°) and AR (13 ± 8°). Frequency of increased FV (>25°) was 47% and of severely increased FV (>35°) was 23% for DDH patients. Proportion of femoral retroversion (FV < 10°) was significantly (p < 0.001) higher in patients AR (31%) compared to DDH patients (17%). 18% of DDH patients had AV > 25° combined with FV > 25°. Of patients with AR, 12% had FV < 10° combined with AV < 10°.

CONCLUSION

Patients with DDH and AR have remarkable sex-related differences of FV and CV. Frequency of severely increased FV > 35° (23%) is considerable for patients with DDH, but 17% exhibited decreased FV, that could influence management. The different combinations underline the importance of patient-specific evaluation before open hip preservation surgery (periacetabular osteotomy and femoral derotation osteotomy) and hip-arthroscopy.

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.

Top 100 cited studies in periacetabular osteotomy for acetabular dysplasia: do lower levels of evidence guide clinical practice?

As no prior study has examined the citations profile of key articles related to periacetabular osteotomy (PAO), our analysis utilized the Web of Science database to (1) identify the most-cited clinical studies relating to PAO in the management of acetabular dysplasia and (2) assess any trends over time with respect to the quality of literature. The top 100 highest-cited studies related to PAO had a mean of 49 citations (range, 6-666 per study). With respect to the level of evidence, most studies had level IV evidence (58%); 1% level I, 16% level II, 28% level III and 2% level V. Most studies were retrospective ( n  = 86); there were 14 prospective studies (including one randomized study). The most common study designs were case series ( n  = 58) and cohort ( n  = 16), followed by matched-cohort ( n  = 13) and case-control ( n  = 6). The mean ± SD Newcastle-Ottawa Scale score was 6.48 ± 1.31. A total of 59 and 41 of the included articles were classified as high risk and high quality, respectively. No studies were classified as very high risk. As a whole, our analysis demonstrated that currently available PAO literature is still of low quality and of low level of evidence. While PAO has been well-documented as a durable procedure for addressing acetabular dysplasia, future research must focus on higher quality, randomized and prospective data to answer key clinical or technique-related topics.

Artificial intelligence-generated hip radiological measurements are fast and adequate for reliable assessment of hip dysplasia

Aims

Hip dysplasia (HD) leads to premature osteoarthritis. Timely detection and correction of HD has been shown to improve pain, functional status, and hip longevity. Several time-consuming radiological measurements are currently used to confirm HD. An artificial intelligence (AI) software named HIPPO automatically locates anatomical landmarks on anteroposterior pelvis radiographs and performs the needed measurements. The primary aim of this study was to assess the reliability of this tool as compared to multi-reader evaluation in clinically proven cases of adult HD. The secondary aims were to assess the time savings achieved and evaluate inter-reader assessment.

Methods

A consecutive preoperative sample of 130 HD patients (256 hips) was used. This cohort included 82.3% females (n = 107) and 17.7% males (n = 23) with median patient age of 28.6 years (interquartile range (IQR) 22.5 to 37.2). Three trained readers’ measurements were compared to AI outputs of lateral centre-edge angle (LCEA), caput-collum-diaphyseal (CCD) angle, pelvic obliquity, Tönnis angle, Sharp’s angle, and femoral head coverage. Intraclass correlation coefficients (ICC) and Bland-Altman analyses were obtained.

Results

Among 256 hips with AI outputs, all six hip AI measurements were successfully obtained. The AI-reader correlations were generally good (ICC 0.60 to 0.74) to excellent (ICC > 0.75). There was lower agreement for CCD angle measurement. Most widely used measurements for HD diagnosis (LCEA and Tönnis angle) demonstrated good to excellent inter-method reliability (ICC 0.71 to 0.86 and 0.82 to 0.90, respectively). The median reading time for the three readers and AI was 212 (IQR 197 to 230), 131 (IQR 126 to 147), 734 (IQR 690 to 786), and 41 (IQR 38 to 44) seconds, respectively.

Conclusion

This study showed that AI-based software demonstrated reliable radiological assessment of patients with HD with significant interpretation-related time savings. Cite this article: Bone Jt Open 2022;3(11):877–884.

Does surgery change pelvic tilt? : an investigation in patients with osteoarthritis of the hip, dysplasia, and femoroacetabular impingement

AIMS

Pelvic tilt is believed to affect the symptomology of osteoarthritis (OA) of the hip by alterations in joint movement, dysplasia of the hip by modification of acetabular cover, and femoroacetabular impingement by influencing the impingement-free range of motion. While the apparent role of pelvic tilt in hip pathology has been reported, the exact effects of many forms of treatment on pelvic tilt are unknown. The primary aim of this study was to investigate the effects of surgery on pelvic tilt in these three groups of patients.

METHODS

The demographic, radiological, and outcome data for all patients operated on by the senior author between October 2016 and January 2020 were identified from a prospective registry, and all those who underwent surgery with a primary diagnosis of OA, dysplasia, or femoroacetabular impingement were considered for inclusion. Pelvic tilt was assessed on anteroposterior (AP) standing radiographs using the pre- and postoperative pubic symphysis to sacroiliac joint (PS-SI) distance, and the outcomes were assessed with the Hip Outcome Score (HOS), International Hip Outcome Tool (iHOT-12), and Harris Hip Score (HHS).

RESULTS

The linear regression model revealed a significant negative predictive association between the standing pre- and postoperative PS-SI distances for all three groups of patients (all p < 0.001). There was a significant improvement in all three outcome measures between the pre- and postoperative values (p < 0.05).

CONCLUSION

There is a statistically significant decrease in pelvic tilt after surgery in patients with OA of the hip, dysplasia, and femoroacetabular impingement. These results confirm that surgery significantly alters the pelvic orientation. Pelvic tilt significantly decreased after total hip arthroplasty, periacetabular osteotomy, and arthroscopy/surgical hip dislocation. The impact of surgery on pelvic tilt should be considered within the therapeutic plan in order to optimize pelvic orientation in these patients.Cite this article: Bone Joint J 2022;104-B(9):1025-1031.

Trajectory for 66 patients treated with periacetabular osteotomy (PAO) and subsequent total hip arthroplasty: a follow-up study including 1378 hips from the Aarhus PAO database

INTRODUCTION

Outcomes for patients treated with PAO and subsequent total hip arthroplasty (THA) remain unclear. We evaluated patient-reported outcomes among patients treated with PAO and subsequent THA and investigated differences in the number of additional surgical procedures after PAO among patients treated with PAO and subsequent THA and patients treated with PAO only.

MATERIALS AND METHODS

1378 hips underwent PAO and subsequently 66 hips were treated with THA. We evaluated the Hip disability and Osteoarthritis Outcome Score (HOOS) and physical activity questions for the 66 hips. Additional surgery after PAO was identified through inquiry to the Danish National Patient Registry.

RESULTS

13% undergoing PAO and subsequent THA reported a HOOS pain score ≤ 50 indicating a clinical failure. The risk difference for hip arthroscopy after PAO within 2 and 4 years was 14% (CI 5-23%) and 26% (CI 15-38%) in favor of hips treated with PAO only. Similarly, the risk difference for screw removal within 2 and 4 years was 19% (CI 8-29%) and 23% (CI 12-34%).

CONCLUSION

87% of patients undergoing PAO and subsequent THA had little or no hip pain. However, these patients received a high number of additional surgeries after PAO. Surgeons and patients may consider if additional surgery after PAO may be the first choice in a series of actions leading to conversion to THA.

Automated quantification of cartilage quality for hip treatment decision support

Purpose

Preservation surgery can halt the progress of joint degradation, preserving the life of the hip; however, outcome depends on the existing cartilage quality. Biochemical analysis of the hip cartilage utilizing MRI sequences such as delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), in addition to morphological analysis, can be used to detect early signs of cartilage degradation. However, a complete, accurate 3D analysis of the cartilage regions and layers is currently not possible due to a lack of diagnostic tools.

Methods

A system for the efficient automatic parametrization of the 3D hip cartilage was developed. 2D U-nets were trained on manually annotated dual-flip angle (DFA) dGEMRIC for femoral head localization and cartilage segmentation. A fully automated cartilage sectioning pipeline for analysis of central and peripheral regions, femoral-acetabular layers, and a variable number of section slices, was developed along with functionality for the automatic calculation of dGEMRIC index, thickness, surface area, and volume.

Results

The trained networks locate the femoral head and segment the cartilage with a Dice similarity coefficient of 88 ± 3 and 83 ± 4% on DFA and magnetization-prepared 2 rapid gradient-echo (MP2RAGE) dGEMRIC, respectively. A completely automatic cartilage analysis was performed in 18s, and no significant difference for average dGEMRIC index, volume, surface area, and thickness calculated on manual and automatic segmentation was observed.

Conclusion

An application for the 3D analysis of hip cartilage was developed for the automated detection of subtle morphological and biochemical signs of cartilage degradation in prognostic studies and clinical diagnosis. The segmentation network achieved a 4-time increase in processing speed without loss of segmentation accuracy on both normal and deformed anatomy, enabling accurate parametrization. Retraining of the networks with the promising MP2RAGE protocol would enable analysis without the need for B1 inhomogeneity correction in the future.

Hip arthroscopy after periacetabular osteotomy for acetabular dysplasia - incidence and clinical outcome

Background

The periacetabular osteotomy (PAO) is the treatment of choice for acetabular dysplasia and has demonstrated improvement in patient reported outcomes measures (PROMs) as well as acceptable long-term survival. However, acetabular dysplasia is also associated with intra-articular lesions that can negatively impact clinical outcome. This study aimed to analyse the incidence, operative findings, and outcomes of hip arthroscopy after PAO.

Methods

This is a single center retrospective study by querying our hip preservation prospectively collected database from 2006 to 2020. All patients having undergone hip arthroscopy after a PAO, with a minimal follow-up of one year, were identified. 202 PAOs were done with a mean age of 28.3 years (12.7 – 53.6) including 39 males and 167 females. Failure was defined as conversion to hip replacement. Demographics, surgical findings, reoperations, and PROMs (pre and post operatively at the last follow-up point only for hips not converted to hip replacement).

Results

Fifteen hips in 15 patients (7.4%) out of 202 PAOs underwent a hip arthroscopy at a mean time of 3.9 years (0.3–10.3) after PAO. There were 2 males, 13 females and the mean age was 29.8 years (18.5–45). 12 hips had no radiological osteoarthritis (Tönnis 0) and 3 hips had early osteoarthritis (Tönnis 1). At time of arthroscopy, all hips had a labral tear, 9 had a chondral damage ≥ Beck 4. Eight hips had labral debridement, 7 had labral repair, 2 had resection of adhesions and 4 underwent a femoral osteochondroplasty. Four hips (27%) were converted to a hip replacement at a mean time of 1.8 years(0.5–3.2) after hip arthroscopy. Patients converted to hip replacement were significantly older (p = 0.01), had a lower post-PAO LCEA (p = 0.01) and a higher post-PAO Tönnis angle (p = 0.02). There were no significant improvements in PROMs.

Conclusion

This study reports a hip arthroscopy reoperation rate after PAO of 7.4%. All three types of dysplasia (uncovered anteriorly, posteriorly, or globally) were present in this cohort. Twenty seven percent of patients were converted to hip replacement and PROMs were not significantly improved by hip arthroscopy. Therefore, this procedure should be approached with some caution.

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

Young 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).

A qualitative study of the impact of a periacetabular osteotomy on patients' lives

AIMS

The aim of this study was to understand the experience of mature patients who undergo a periacetabular osteotomy (PAO), a major hip-preserving surgical procedure that treats symptomatic hip dysplasia by realigning the acetabulum. Our aim was to improve our understanding of how the operation affected the lives of patients and their families, with a long-term goal of improving their experience.

METHODS

We used a phenomenological approach with in-depth, semi-structured interviews to investigate the experience of seven female patients, aged between 25 and 40 years, who underwent a PAO. A modified homogeneity sampling approach coupled with criterion sampling was used. Inclusion criteria involved having at least one child at home and being in a committed relationship with a spouse or partner.

RESULTS

Analysis of interview transcripts revealed five major themes: feelings of frustration before having a treatment plan; fear of the operation; the importance of understanding the procedure in order to feel in control of their care; feelings of helplessness, dependence, and depression during recovery; and the need for support during recovery.

CONCLUSION

Our findings suggest that both the physical and psychosocial burdens of undergoing a PAO are great, with a major impact on the patient and their family. Many important issues lie outside the scope of what healthcare teams currently address. Cite this article: Bone Joint J 2022;104-B(7):781-785.

Risk Factors for Composite Failure of Hip Dysplasia Treated With Periacetabular Osteotomy: A Minimum 10-Year Follow-up

INTRODUCTION

Periacetabular osteotomy (PAO) is a common surgical treatment of prearthritic hip dysplasia in young adults, but there are few long-term studies of clinical outcomes. The purpose of this investigation was to report a minimum 10-year clinical follow-up of hip dysplasia treated with PAO and identify risk factors for composite failure.

METHODS

We identified 151 patients (198 hips) who underwent PAO to treat hip dysplasia at a single institution. Enrolled subjects completed a series of six patient-reported outcome instruments and provided information about subsequent surgeries. We defined composite failure as conversion to total hip arthroplasty or modified Harris Hip Score ≤70. Logistic regression with generalized estimating equations was used to evaluate the relationships between odds of failure and potential predictor variables in univariate and multivariate analyses.

RESULTS

A total of 124 subjects (167 hips) with a minimum 10-year follow-up were enrolled. The median time from PAO to the final follow-up was 13 years (range 10-18 years). There were 71 hips that met criteria for failure: 32 with total hip arthroplasty and 39 with modified Harris Hip Score ≤70. Univariate logistic regression analyses revealed multiple preoperative factors that predicted composite failure: increased age and body mass index, osteoarthritis (OA), and more severe acetabular dysplasia. Postoperative factors that predicted failure included lateral undercoverage and formation of heterotopic ossification (HO). The final multivariate model identified body mass index ≥30 kg/m2 (odds ratio [OR], 3.84 [95% confidence interval (CI), 1.68-8.78], P = 0.001), higher preoperative Tönnis grade OA (OR, 2.65 [95% CI, 1.50-4.66], P < 0.001), and HO formation (OR, 16.52 [95% CI, 2.08-135.96], P = 0.009) as independent predictors of failure.

CONCLUSIONS

This study corroborates current hip dysplasia literature, identifying increasing age and presence of preoperative OA as risk factors for composite failure in univariate analyses. In addition, we found that obesity and HO formation were independent predictors of persistent hip dysfunction.

LEVEL OF EVIDENCE

Therapeutic Level IV.

The relationship between patient-reported outcomes and preoperative pain characteristics in patients who underwent total hip arthroplasty

Aims

This study aims to answer the following questions in patients with hip osteoarthritis (OA) who underwent total hip arthroplasty (THA): are patient-reported outcome measures (PROMs) affected by the location of the maximum severity of pain?; are PROMs affected by the presence of non-groin pain?; are PROMs affected by the severity of pain?; and are PROMs affected by the number of pain locations?

Methods

We reviewed 336 hips (305 patients) treated with THA for hip OA from December 2016 to November 2019 using pain location/severity questionnaires, modified Harris Hip Score (mHHS), Hip Outcome Score (HOS), international Hip Outcome Tool (iHOT-12) score, and radiological analysis. Descriptive statistics, analysis of covariance (ANCOVA), and Spearman partial correlation coefficients were used.

Results

There was a significant difference in iHOT-12 scores between groups experiencing the most severe pain in the groin and the trochanter (p = 0.039). Additionally, more favourable mHHS scores were related to the presence of preoperative pain in trochanter (p = 0.049), lower back (p = 0.056), lateral thigh (p = 0.034), and posterior thigh (p = 0.005). Finally, the maximum severity of preoperative pain and number of pain locations had no significant relationship with PROMs (maximum severity: HHS: p = 0.928, HOS: p = 0.163, iHOT-12 p = 0.233; number of pain locations: HHS: p = 0.211; HOS: p = 0.801; iHOT-12: p = 0.112).

Conclusion

Although there was a significant difference in iHOT-12 scores between patients with the most severe pain in the groin or trochanter, and the presence of pain in the trochanter, lower back, lateral thigh, or posterior thigh was related to higher mHHS scores, the majority of preoperative pain characteristics did not have a significant impact on outcomes. Therefore, a broad array of patients with hip OA might expect similar, favourable outcomes from THA notwithstanding preoperative pain characteristics. Cite this article: Bone Jt Open 2022;3(4):332–339.

Periacetabular Osteotomy in United States Military Personnel: Results From an Interservice Hip Preservation Practice

Background:

Untreated or residual developmental dysplasia of the hip may cause significant morbidity. Periacetabular osteotomy (PAO) allows for surgical reorientation of the acetabulum but requires a significant recovery period. Because of the physical demands of active military service, hip dysplasia or its treatment with PAO may cause a significant impact on the careers of affected personnel.

Purpose:

To measure the impact of symptomatic acetabular dysplasia and its treatment with PAO on the physical readiness of personnel in the United States Armed Forces.

Study Design:

Case series; Level of evidence, 4.

Methods:

Records from an interservice hip-preservation practice were reviewed for all patients who underwent PAO while on active duty from January 2014 through April 2017. Collected information included branch of service, military occupation, preoperative duty restrictions related to the hip, and concomitant surgical procedures. Patients were evaluated for a minimum of 24 months and assessed for their time to return to duty, continued duty restrictions, and referrals to the medical evaluation board.

Results:

Twenty patients (15 female, 5 male) underwent a PAO while on active duty during the period assessed. The mean patient age at surgery was 25.9 years, and the mean follow-up was 3.3 years (range, 2.3-5.4 years). In the 6 months preceding surgery, 94% of the 17 patients with available records were on duty restrictions specific to their hip (14 temporary, 2 permanent). After PAO, 35% of patients (n = 7) returned to full duty and 85% were able to remain on active duty (n = 12) or complete their military service commitments (n = 5) without noted medical disability. Three patients were medically discharged after PAO, with 1 patient referred due to hip pathology.

Conclusion:

Acetabular dysplasia significantly affects physical readiness in affected servicemembers, with 94% requiring duty restrictions. PAO allowed 85% of patients to return to military service, and 1 in 3 were able to return to full duty.

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

BACKGROUND

Femoroacetabular impingement (FAI) after periacetabular osteotomy (PAO) may be affected by both anterior acetabular coverage and femoral head shape. This study aimed to radiographically evaluate the relationship of the combination of acetabular coverage and femoral head shape with the occurrence of FAI after curved PAO.

METHODS

In this study, 76 hip joints from patients with symptomatic developmental dysplasia of the hip underwent curved PAO. The relationship between the combined postoperative anterior center-edge and alpha angles (ie, the combination angle) and the occurrence of postoperative FAI was evaluated. Clinical factors and the preoperative and postoperative 3-dimensional center-edge angles, acetabular versions, femoral versions, radiographic alpha angles of the femoral head, and the combination angle were measured and compared to clinical outcomes.

RESULTS

The modified Harris Hip Scores, University of California, Los Angeles activity scores, and acetabular coverage angles were significantly improved following curved PAO. Receiver operator characteristic curve analysis demonstrated that the combination angle over 108° may be a predictive factor for the occurrence of FAI after curved PAO. Multivariate analysis demonstrated that an age <40 years (odds ratio 6.6, 95% confidence interval 1.2-36.4, P = .037) and a combination angle <108° (odds ratio 9.2, 95% confidence interval 1.7-50.0, P = .010) were significantly associated with modified Harris Hip Scores ≧90 points.

CONCLUSION

A combination angle >108° may be a predictive factor for the occurrence of FAI after curved PAO and impaired clinical outcomes. To avoid postoperative FAI, we propose that osteochondroplasty of the femoral head should be performed for patients with preoperative combination angles >90°.