Complications and outcome after periacetabular osteotomy - influence of surgical approach

Femoro-Epiphyseal Acetabular Roof Index Values on Anteroposterior Pelvic Radiographs Significantly Increase With Hip Adduction and Decrease With Abduction

PURPOSE

To investigate the impact of hip adduction and abduction on the femoro-epiphyseal acetabular roof (FEAR) index using conventional anteroposterior pelvic radiographs of patients with borderline hip dysplasia (BHD).

METHODS

Patients with BHD (lateral center edge angle [LCEA] with values of 18° ≤ LCEA <25°) and who were subject to periacetabular osteotoym were selected from a consecutive retrospective cohort from January 2009 to January 2016. The hip ad-/abduction (adduction handled as negative values) and the FEAR index (lateral opening angles handled as positive values) were measured in the initially standardized acquired pelvic radiographs. Thereafter, using surgical planning software, different degrees of hip adduction and abduction were simulated from 20° of adduction to 30° of abduction, and the FEAR index was measured at each position. Pearson correlation was used to identify a potential correlation between the hip ad-/abduction and the FEAR index.

RESULTS

Eighty-nine hips were included. Initial radiographs showed unintentional mean ad-/abduction of -5.3° ± 3.1° (range, -14° to 2°). The mean FEAR index at the initial ad-/abduction angle was -3.6° ± 7.2° (range, -18.0° to 16.0°) and was significantly different from neutral position (0° of ad-/abduction) -9.2° ± 7.0° (range, -27.0° to 10.0°) (P < .001). The FEAR index was negatively correlated to the hip ad-/abduction angle (r = 1, P < .001), with lower values for the FEAR index with the hip in abduction.

CONCLUSIONS

Significant differences in FEAR index measurements were observed depending on hip ad-/abduction on pelvic radiographs. A linear change of the FEAR index of 5° per 5° of hip adduction or abduction could be demonstrated, with adduction resulting in increasing and abduction in decreasing values for the FEAR index.

LEVEL OF EVIDENCE

Level III, diagnostic study.

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

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

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.

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

OBJECTIVE

Given the intricate challenges and potential complications associated with periacetabular osteotomy (PAO) for developmental dysplasia of the hip (DDH). Our study aimed to compare the clinical and imaging benefits and drawbacks of two surgical approaches, the modified Stoppa combined iliac spine approach and the modified Smith-Peterson approach, for treating PAO and to provide guidance for selecting clinical approaches.

METHODS

A retrospective analysis of 56 patients with 62 DDHs was conducted from June 2018 to January 2022. The experimental group underwent surgery via the modified Stoppa combined iliac spine approach, while the control group underwent surgery via the modified Smith-Peterson approach for periacetabular osteotomy and internal fixation. Basic statistical parameters, including age, sex, BMI, and preoperative imaging data, were analyzed. Differences in surgical time, intraoperative blood loss, and postoperative imaging data were compared, as were differences in preoperative and postoperative imaging data between the two groups.

RESULTS

There were 28 hips in the experimental group and 34 in the control group. Moreover, there was no significant difference in the basic parameters between the experimental and control groups. Before and after the operation, for the LCE angle, ACE angle, and Tonnis angle, there was no significant difference in acetabular coverage (p > 0.05). However, there were significant differences between the two groups in terms of the above four indicators before and after the operation (p < 0.05). After the operation, the experimental group exhibited significant increases in both lateral and anterior acetabular coverage of the femoral head. However, the experimental group had longer operation times and greater bleeding volumes than did the control group. Despite this, the experimental group demonstrated significant advantages in protecting the lateral femoral cutaneous nerve compared to the control group.

CONCLUSION

The modified Stoppa combined iliac spine approach can be considered a practical approach for PAO and is more suitable for patients with DDH who plan to be treated by one operation than the classic modified Smith-Peterson approach for PAO.

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

PURPOSE

We conducted a retrospective analysis of prospectively collected data to evaluate (1) the extent of surgical correction following minimally invasive periacetabular osteotomy, (2) improvements in functional outcomes and any potential predictors for favourable outcome, and (3) complications after minimally invasive periacetabular osteotomy.

METHODS

A total of 352 minimally invasive periacetabular osteotomy procedures were performed on 312 hip dysplasia patients between 2013 and 2020. Radiological parameters such as lateral centre edge angle, acetabular index, and Tönnis grade of arthritis were calculated. Patients also completed a range of patient reported outcome measures. Wilcoxon signed-rank tests were performed to assess for differences between patient reported outcome measures and radiological outcomes across the follow-up periods. Univariate linear regression and logistic regression were used to assess for predictors of change in functional outcome.

RESULTS

Patients had a significant correction in mean lateral centre edge angle from 17.2° to 35.3° (p < 0.001) and mean acetabular index from 13.2° to - 0.82°. At one year follow-up all patient reported outcome measures were significantly greater than their baseline measurements and this improvement was maintained at two years. Changes in patient reported outcome measures were independent of radiological parameters such as change in the lateral centre edge angle and acetabular index, pre-operative Tönnis grade, and patient factors such as age and sex. A total of 5.11% of patients developed post-operative complications, with four requiring posterior column fixation. Four patients (1.12%) needed a total hip replacement.

CONCLUSION

Minimally invasive periacetabular osteotomy is a safe procedure that provides significant functional outcome improvements following surgery at six months which is maintained at two years. More than three-fourths of patients achieved improvement of iHOT-12 score beyond the minimal clinically important difference and more than half of the patients achieved substantial clinical benefit for iHOT-12 score.

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.

Incidence and clinical outcome of lateral femoral cutaneous nerve injury after periacetabular osteotomy

Aims

Lateral femoral cutaneous nerve (LFCN) injury is a complication after periacetabular osteo-tomy (PAO) using an anterior approach, which might adversely affect the outcome. However, no prospective study has assessed the incidence and severity of this injury and its effect on the clinical outcomes over a period of time for longer than one year after PAO. The aim of this study was to assess the incidence and severity of the symptoms of LFCN injury for ≥ three years after PAO and report its effect on clinical outcomes.

Methods

A total of 40 hips in 40 consecutive patients who underwent PAO between May 2016 and July 2018 were included in the study, as further follow-up of the same patients from a previous study. We prospectively evaluated the incidence, severity, and area of symptoms following LFCN injury. We also recorded the clinical scores at one year and ≥ three years postoperatively using the 36-Item Short Form Health Survey (SF-36) and Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) scores.

Results

A total of 20 patients (50%) had symptoms of a LFCN injury at one year after PAO. At ≥ three years postoperatively, the symptoms had completely resolved in seven of these patients and 13 (33%) had persistent symptoms. The severity and area of symptoms did not significantly differ between one and ≥ three years postoperatively. The JHEQ showed significant differences in the patient satisfaction and mental scores between those with and those without sypmtoms of LFCN injury at ≥ three years postoperatively, while there was no significant difference in the mean SF-36 scores.

Conclusion

The incidence of LFCN injury after PAO using an anterior approach is high. The outcome of PAO, ≥ three years postoperatively, is poorer in patients with persistent symptoms from a perioperative LFCN injury, in that patient satisfaction and mental health scores are adversely affected.

Treatment of bilateral developmental dysplasia of the hip joint with an improved technique: A case report

BACKGROUND

Developmental dysplasia of the hip (DDH) is a common osteoarticular deformity in pediatric orthopedics. A patient with bilateral DDH was diagnosed and treated using our improved technique "(powerful overturning acetabuloplasty)" combined with femoral rotational shortening osteotomy.

CASE SUMMARY

A 4-year-old girl who was diagnosed with bilateral DDH could not stand normally, and sought surgical treatment to solve the problem of double hip extension and standing. As this child had high dislocation of the hip joint and the acetabular index was high, we changed the traditional acetabuloplasty to "powerful turnover acetabuloplasty" combined with femoral rotation shortening osteotomy. During the short-term postoperative follow-up (1, 3, 6, 9, 12, and 15 months), the child had no discomfort in her lower limbs. After the braces and internal fixation plates were removed, formal rehabilitation training was actively carried out.

CONCLUSION

Our "powerful overturning acetabuloplasty" combined with femoral rotational shortening osteotomy is feasible in the treatment of DDH in children. This technology may be widely used in the clinic.

Step-cut osteotomy of the anterior superior iliac spine for increased visualisation in the Levine approach for Bernese periacetabular osteotomy surgery

BACKGROUND

Hip dysplasia can lead to pain and dysfunction in the young adult. Acetabular undercoverage leads to abnormal joint loading and results in joint degeneration, accelerating need for arthroplasty in this patient population. Conceptually, treatment focuses on increasing acetabular coverage in the form of periacetabular osteotomy. The procedure can be performed through the iliofemoral approach, and performing an anterior superior iliac spine (ASIS) osteotomy can enhance the visualisation in this approach. Several techniques have been described for ASIS osteotomy.

AIM

The purpose this study was to report on step-cut technique for ASIS osteotomy during the Bernese periacetabular osteotomy procedure to enhance visualisation when utilising the iliofemoral approach.

SURGICAL TECHNIQUE

This step-cut technique enhances stability at the osteotomy site, and minimises soft tissue dissection to reduce pain and assists with maintaining a stable fixation construct postoperatively.

RESULTS

There were no nonunions and minimal morbidity to the lateral femoral cutaneous nerve injury in cohort of 86 patients while utilising this technique.

CONCLUSIONS

We recommend using this step-cut ostetomy of the ASIS during Bernese periactetabular osteotomy for benefit of increasing exposure while maintaining a low complication profile.

Augmented reality-guided pelvic osteotomy of Ganz: feasibility in cadavers

INTRODUCTION

The periacetabular osteotomy is a technically demanding procedure with the goal to improve the osseous containment of the femoral head. The options for controlled execution of the osteotomies and verification of the acetabular reorientation are limited. With the assistance of augmented reality, new possibilities are emerging to guide this intervention. However, the scientific knowledge regarding AR navigation for PAO is sparse.

METHODS

In this cadaveric study, we wanted to find out, if the execution of this complex procedure is feasible with AR guidance, quantify the accuracy of the execution of the three-dimensional plan, and find out what has to be done to proceed to real surgery. Therefore, an AR guidance for the PAO was developed and applied on 14 human hip cadavers. The guidance included performance of the four osteotomies and reorientation of the acetabular fragment. The osteotomy starting points, the orientation of the osteotomy planes, as well as the reorientation of the acetabular fragment were compared to the 3D planning.

RESULTS

The mean 3D distance between planned and performed starting points was between 9 and 17 mm. The mean angle between planned and performed osteotomies was between 6° and 7°. The mean reorientation error between the planned and performed rotation of the acetabular fragment was between 2° and 11°.

CONCLUSION

The planned correction can be achieved with promising accuracy and without serious errors. Further steps for a translation from the cadaver to the patient have been identified and must be addressed in future work.

A social media analysis of patient-perceived complications following periacetabular osteotomy (PAO): a retrospective observational study

BACKGROUND

Social media is a popular resource for patients seeking medical information and sharing experiences. Periacetabular osteotomy (PAO) is an accepted treatment for symptomatic acetabular dysplasia with a low published complication profile in specialty centers. Little is known regarding patient reporting of complications on social media following PAO. The purpose of this study was to describe the patient-perceived complications of PAO posted on social media and analyze how additional factors (postoperative timeframe, concomitant surgery) correlate with these complication posts.

METHODS

Facebook and Instagram were queried from 02/01/18-02/01/23; Twitter was searched over an extended range back to 02/01/11. Facebook posts (1054) were collected from the two most populated interest groups; "Periacetabular Osteotomy" and "PAO Australia." Instagram posts (1003) and Tweets (502) were found using the same five most popular hashtags: #PAOwarrior, #periacetabularosteotomy, #periacetabularosteotomysurgery, #PAOsurgery, and #PAOrecovery. Posts were assessed for demographic data, perspective, timing (early postoperative or late postoperative), additional surgeries, type of complication, and post engagement.

RESULTS

Facebook posts (1054), Instagram posts (1003), and Tweets (502) were assessed; 13.6% of posts included a complication. The majority of complications were reported > 6 months postoperatively with excessive pain being the most common complication (57.2%), including chronic pain (41.8%), acute pain (6.7%), and nerve pain (8.8%). Bony complications (6.7%), neurologic/psychiatric complications (3.8%), swelling (1.7%), infection (1.4%), other specified complications (16.2%), and unspecified complications (10.2%) were reported. Complication posts were found to be correlated with postoperative timeframe and concomitant surgery. Post engagement decreased in complication-related posts.

CONCLUSIONS

Few patients posted a perceived complication associated with PAO surgery. Of those who did, the majority reported unmanageable pain during the late postoperative period. Posts including a perceived complication were found to be positively correlated with postoperative timeframe and negatively correlated with concomitant surgery. This study found a higher pain complication rate, but a lower overall complication rate compared to prior studies. Considering the social media reported complications of PAO patients in addition to traditional outcome measures reveals which aspects of postoperative recovery are most important to patients themselves.

Long-term patient-centred outcomes of periacetabular osteotomy in a large consecutive series

Aims

We assessed the long-term outcomes of a large cohort of patients who have undergone a periacetabular osteotomy (PAO), and sought to validate a patient satisfaction questionnaire for use in a PAO cohort.

Methods

All patients who had undergone a PAO from July 1998 to February 2013 were surveyed, with several patient-reported outcome measures (PROMs) and radiological measurements of preoperative acetabular dysplasia and postoperative correction also recorded. Patients were asked to rate their level of satisfaction with their operation in achieving pain relief, restoration of activities of daily living, ability to perform recreational activity, and their overall level of satisfaction with the procedure.

Results

A total of 143 PAOs were performed between 1998 and 2013. Of those, 90 postoperative surveys were returned. Only 65 patients (73 hips) had both pre- and postoperative radiographs available for measurement. The mean time to follow-up was 15 years (6.5 to 20). Most patients were female (91%), with a mean age of 26.4 years (14.9 to 48.3) at the time of their surgery. A statistically significant improvement in radiological correction was detected in all hips (p < 0.001). A total of 67 patients (92.3%) remained either very satisfied or satisfied with their PAO. The internal consistency of the patient satisfaction questionnaire, measured using Cronbach's α, ranged from 0.89 to 0.94 indicating 'good' to 'excellent' reliability.

Conclusion

Outcomes of importance to patients undergoing a PAO include several key domains: pain relief, improve activities of daily living, and improve recreational ability. Our study demonstrates high rates of long-term patient satisfaction in all domains, and found the patient satisfaction questionnaire to be a valid and reliable instrument for use in this cohort.

The periacetabular osteotomy: angulation of the supraacetabular osteotomy for quantification of correction

BACKGROUND

Malcorrection of the acetabular fragment in periacetabular osteotomy (PAO) is associated with inferior outcomes. 2-dimensional radiographic parameters are being used for intraoperative verification of a satisfactory result. After reorientation of the fragment, the acetabular version must be verified with an intraoperative radiograph. In the case of an unsatisfactory correction, a reorientation would be required. A slim and radiation-free intraoperative navigation method to directly quantify the correction is highly desirable.

AIM

To find out whether the measurable angulation of the supraacetabular osteotomy can be used for this purpose.

METHODS

To determine the angulation, 13 consecutive patients who underwent a PAO were investigated. The preoperative and postoperative standard radiographs as well as CT scans were available. The surgically produced alteration of radiographic parameters was correlated to tilting and spreading of the supraacetabular osteotomy planes.

RESULTS

Tilting of the supraacetabular osteotomy planes correlates strongly to alteration of the lateral centre-edge angle (LCEA) and the acetabular index (ACI), whereas spreading of the same planes showed also a strong correlation, but to the LCEA only. 1° of tilting resulted in a 0.2° alteration of the LCEA and a 0.5° alteration of the ACI, whereas 1° of spreading resulted in a 0.5° alteration of the LCEA.

CONCLUSIONS

This study shows that the measurable angulation of the supraacetabular osteotomy planes can be used to monitor the three-dimensional reorientation of the acetabular fragment in PAO. As long as sophisticated modalities are lacking, this technique offers an easy way to intraoperatively navigate the correction in PAO.

Factors influencing patient-reported outcomes following periacetabular osteotomy and open osteochondroplasty in the setting of borderline hip dysplasia

Aims

This study reports mid-term outcomes after periacetabular osteotomy (PAO) exclusively in a borderline hip dysplasia (BHD) population to provide a contrast to published outcomes for arthroscopic surgery of the hip in BHD.

Methods

We identified 42 hips in 40 patients treated between January 2009 and January 2016 with BHD defined as a lateral centre-edge angle (LCEA) of ≥ 18° but < 25°. A minimum five-year follow-up was available. Patient-reported outcomes (PROMs) including Tegner score, subjective hip value (SHV), modified Harris Hip Score (mHHS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were assessed. The following morphological parameters were evaluated: LCEA, acetabular index (AI), α angle, Tönnis staging, acetabular retroversion, femoral version, femoroepiphyseal acetabular roof index (FEAR), iliocapsularis to rectus femoris ratio (IC/RF), and labral and ligamentum teres (LT) pathology.

Results

The mean follow-up was 96 months (67 to 139). The SHV, mHHS, WOMAC, and Tegner scores significantly improved (p < 0.001) at last follow-up. According to SHV and mHHS, there were three hips (7%) with poor results (SHV < 70), three (7%) with a fair score (70 to 79), eight (19%) with good results (80 to 89), and 28 (67%) who scored excellent (> 90) at the last follow-up. There were 11 subsequent operations: nine implant removals due to local irritation, one resection of postoperative heterotopic ossification, and one hip arthroscopy for intra-articular adhesions. No hips were converted to total hip arthroplasty at last follow-up. The presence of preoperative labral lesions or LT lesions did not influence any PROMs at last follow-up. From the three hips that had poor PROMs, two have developed severe osteoarthritis (> Tönnis II), presumably due to surgical overcorrection (postoperative AI < -10°).

Conclusion

PAO is reliable in treating BHD with favourable mid-term outcomes. Concomitant LT and labral lesions did not negatively influence outcomes in our cohort. Technical accuracy with avoidance of overcorrection is essential in achieving successful outcomes.

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.

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.

What is the agreement between intraoperative fluoroscopy and postoperative radiographs in Bernese periacetabular osteotomy?

BACKGROUND

It is important to reorient the acetabular fragment into an optimal position and version to ensure a good long-term outcome after Bernese periacetabular osteotomy (PAO). Unfortunately, the intraoperative balance between overcorrection and undercorrection remains challenging for the surgeon. The purpose of this study was to answer two questions: (1) Does the femoral head coverage measured on intraoperative fluoroscopy agree with that measured on postoperative radiography? (2) What is the reliability of intraoperative fluoroscopy in identifying hip center correction in PAO?

METHODS

A total of 173 patients (173 hips) who underwent PAO for developmental dysplasia of the hip (DDH) at our center from July 01, 2020, to December 31, 2020, were retrospectively reviewed. Imaging data from 111 patients (female/male, 98/13; right/left, 72/39; mean age, 28.93 years) were included in this study. The analysis included measurement of the lateral center-edge angle (LCEA), acetabular index (AI), anterior wall index (AWI), posterior wall index (PWI), extrusion index (EI), and medial offset distance (MO). These measurements were acquired from intraoperative fluoroscopic images and postoperative radiographs and compared by paired t test using SPSS (version 24.0). Significance was determined at a p value of < 0.05. Bland-Altman analysis, conducted using GraphPad Software (version 9), was used to quantify the agreement between intraoperative fluoroscopic images and postoperative radiographs.

RESULTS

The means (standard deviations, SDs) of the LCEA, AI, AWI, PWI, EI, and MO obtained on intraoperative fluoroscopy were 32.86° (5.73°), 0.66° (5.55), 0.29 (0.10), 0.75 (0.17), 11.15% (6.50%), and 8.49 mm (3.68 mm), respectively. On postoperative radiography, the corresponding values were 32.91° (6.31°), 1.63° (5.22°), 0.29 (0.15), 0.85 (0.14), 11.27% (7.36%), and 9.60 mm (3.79 mm). The differences in the LCEA, AWI, and EI acquired from intraoperative fluoroscopic images and postoperative radiographs were not significant (p = 0.90, 0.95, and 0.83, respectively), but those in the AI, PWI, and MO were significant (p < 0.05). The mean biases (95% limits of agreement) of the LCEA, AI, AWI, PWI, EI, and MO were - 0.04 (- 6.85), - 0.97 (- 7.78), 0 (- 0.30), - 0.11 (- 0.36), - 0.12 (- 11.92), and - 1.11 (- 5.51), respectively.

CONCLUSION

The LCEA, EI, and AWI can be used to reliably predict postoperative femoral head coverage at the level of 2D graphics. Acetabular inclination can be cautiously assessed using AI on intraoperative fluoroscopy. In the absence of intraoperative 3D image evaluation, the AWI and PWI demonstrate acceptable agreement between fluoroscopy and radiography in assessing the acetabular version. Although the MO shows slight bias, it can be helpful in properly positioning the acetabulum during PAO.

A minimally invasive periacetabular osteotomy improves the radiographic parameters and functional outcomes in the treatment of developmental dysplasia of the hip in adolescents and adults: surgical technique and early results

PURPOSE

To introduce West China Hospital periacetabular osteotomy (WCH PAO) for acetabular dysplasia in adolescent and young adult patients and evaluate the early clinical results of WCH PAO.

METHODS

A retrospective analysis of 34 patients with developmental dysplasia of the hip was performed from October 2019 to April 2021. Baseline data with surgical time and perioperative blood-loss volume were retrieved from medical record systems. The lateral center-to-edge angle (LCEA), acetabular inclination (AI), hip disability and osteoarthritis outcome score (HOOS), University of California Los Angeles (UCLA), and modified Harris hip score (mHHS) were compared preoperatively and postoperatively.

RESULTS

All patients had significant postoperative radiology improvements, including LCEA and AI. The LCEA was improved from 12.9 to 33.2°, and the AI was decreased from 27.2 to 8.5°. In addition, hip functional outcomes, including HOOS, UCLA and mHHS, were improved. The UCLA was improved from 3.9 to 6.3, and the HOOS was decreased from 71.0 to 10.5. The Harris hip score improved from 50.8 before surgery to 87.4 after surgery. The mean operative time was 155 min (range 120 to 190 min), and the mean intra-operative blood loss was 580.2 ± 285.5 ml. Furthermore, no major complications, including nerve injury or bone nonunion, occurred in the cohort study.

CONCLUSION

WCH PAO is a minimally invasive surgical method for acetabular dysplasia in adolescent and young adult patients who that simplifies the surgical procedure and decreases the incidence of complications related to osteotomy.

Acetabular retroversion does not affect outcome in primary hip arthroscopy for femoroacetabular impingement

PURPOSE

The surgical treatment of femoral-acetabular impingement syndrome (FAIS) in patients with acetabular retroversion (AR) is arthroscopical or by a reverse periacetabular osteotomy (PAO). The purpose of the present study was to investigate the results after arthroscopic treatment of FAIS in patients with and without radiographic signs of AR in a large, prospective cohort from the Danish Hip Arthroscopy Registry (DHAR). The hypothesis was there is no difference in clinical outcome between the two groups.

METHODS

Data on 4914 hip arthroscopies performed during 2012-2019 were obtained from DHAR. Patients with radiographic signs of osteoarthritis (Tönnis > 1), hip dysplasia (CEA < 25°), other hip pathologies or previous hip surgery were excluded. The clinical outcomes for patients with AR [defined by a positive posterior wall sign (PWS) in combination with a positive Ischial Spine Sign (ISS)] and patients without AR (no PWS, no ISS) were analyzed 1 and 2 years after surgery. The primary outcomes were the six domains of the Copenhagen Hip and Groin Outcome score (HAGOS), while secondary outcomes were the Hip Sports Activity Scale (HSAS), a visual analogue pain scale (VAS) and a numeric rating scale (NRS) for pain.

RESULTS

A total of 3135 hip arthroscopies were included, of which 339 had AR, 1876 did not, and 920 presented one of the two signs (PWS and ISS). There were no statistically significant differences 1 and 2 years after surgery (n.s.) between patients with and without AR in HAGOS domain scores, HSAS, VAS, or NRS. Both groups showed improvement at both follow-ups. The two groups did not differ in relation to intraoperative findings and the procedures they have had.

CONCLUSION

The outcome 1 and 2 years after arthroscopic treatment of FAIS is not different for patients with and without AR.

LEVEL OF EVIDENCE

III.

Periacetabular osteotomy with or without femoral osteotomy for the treatment of hip subluxation in children and young adults with cerebral palsy

Background

This study is aimed to investigate retrospectively the radiographic and clinical outcomes in children and young adults with cerebral palsy (CP) undergoing periacetabular osteotomy (PAO) with or without femoral osteotomy (FO) for hip subluxation.

Methods

A consecutive cohort of twenty-one patients (23 hips) with symptomatic CP hip subluxation were treated with PAO with or without FO and reviewed retrospectively. Two patients (2 hips) were excluded due to insufficient follow-up and lost to follow-up, respectively. The Reimers migration percentage, lateral center-edge angle (LCEA), Sharp angle, neck-shaft angle (NSA), femoral anteversion (FNA), Gross Motor Function Classification System (GMFCS) and hip pain were assessed.

Results

Twenty-one hips (19 patients) with CP treated with PAO with or without FO were included. Five hips received PAO. Sixteen hips underwent PAO with FO. Mean age at surgery was 19 ± 6 and 15 ± 4 years for PAO and PAO plus FO, respectively. Mean follow-up was 44.0 ± 28.3 months for PAO and 41.5 ± 17.2 months for PAO + FO. All hips were painful before surgery and painless at final visits. The GMFCS improved by one level in 10 of 19 patients. There was significant increase in LCEA (p < 0.001) and decrease in the Reimer’s MP (p < 0.001), NSA (p < 0.001) and Tonnis angle(p < 0.001) postoperatively. Resubluxation occurred in 7 hips (30%) due to insufficient correction and loosening of fixation. Nervus cutaneus femoris lateralis was impaired in 4 patients after surgery. There was no avascular necrosis of the femoral head, resubluxation or infection.

Conclusion

PAO with or without FO can be effective for children and young adults with concomitant hip subluxation and CP.

Treatment of symptomatic hip dysplasia by posterolateral small incision assisted Bernese periacetabular osteotomy

Background

For periacetabular osteotomy, traditional approaches usually have a long learning curve. We aimed to evaluate the postoperative results and complications of periacetabular osteotomy under a new double-incision approach.

Methods

The records of 58 consecutive patients (65 hips) who underwent periacetabular osteotomy using the new approach were retrospectively reviewed and evaluated. There were 52 women and 6 men with a mean age of 28.1 years at the time of surgery.

Results

The average follow-up period was 35.2 months, during which no patients were converted to total hip arthroplasty. Complications included 6 hips (9.2%) with nerve dysesthesias and 1 hip (1.5%) with delayed wound healing. The mean operative time and intraoperative blood loss were 88.6 min and 402.8 ml, respectively. The mean modified Harris hip score had improved from 72.2 points preoperatively to 91.3 points at the last follow-up. Fifty-five patients (62 hips, 95.4%) were satisfied to their outcomes, and good preoperative functional score was associated with a satisfactory outcome. Furthermore, the average lateral center–edge angle, anterior center–edge angle and acetabular index angle were corrected well after surgery.

Conclusion

Periacetabular osteotomy using modified Smith-Petersen or Bikini approach with posterolateral assisted small incision can be performed safely and with satisfactory results. In addition, this technique shortens the learning curve, and reduces the operating complexity, especially for beginner.

Hip survivorship following the Bernese periacetabular osteotomy for the treatment of acetabular dysplasia: A systematic review and meta-analysis

INTRODUCTION

The Bernese periacetabular osteotomy (PAO) is a popular joint-preservation technique aimed at addressing the structural and biomechanical abnormalities associated with acetabular dysplasia. However, the prognostic factors and long-term survivorship of the native hip, with failure defined as conversion to total hip arthroplasty (THA), is poorly understood. Our study aims to address the following: (1) What is the estimated duration of survival of the native hip post-PAO, (2) What are some prognostic factors of functional outcome and (3) What is the complication rate and complications associated with PAO.

HYPOTHESIS

The Bernese PAO is able to result in favourable mid- to long-term outcomes conditional on a stringent patient selection criteria.

MATERIALS AND METHODS

A systematic review was performed using the PRISMA guidelines. All studies that reported on the outcomes of isolated Bernese PAO for the treatment of acetabular dysplasia were included.

RESULTS

A total of 24 studies (3471 patients, 3655 hips) were included at a mean follow-up duration of 54.2months (range: 1-336months). In total, 208 hips (6.03%; 95% CI: 5.25-6.94%) converted to THA at a mean duration of 4.71years (range: 1-240months). Univariate analysis identified advanced age beyond a follow-up duration of 6years (p=0.001) and preoperative Tönnis grade 2 and above (p<0.001) to be the most significant negative prognostic factors. Beyond a follow-up duration of 2years, intraoperative fluoroscopy proved to be a significant positive prognostic factor (p<0.001). Indications for PAO, obesity and gender were not found to be significant predictors of failure. Our study found the complication rate to be 23.5% (95% CI: 21.6-25.6%). The most common complications detailed are transient lateral femoral cutaneous nerve dysesthesia (8.24%; 95% CI: 7.02-9.65%), stress fracture (5.28%; 95% CI: 4.31-6.89%) and the delayed union, non-union or pseudoarthrosis of the ramus not necessitating surgical correction (3.73%, 95% CI: 2.93-4.75%).

DISCUSSION

PAO alters the natural history of the dysplastic hip with a 10- and 20-year survivorship of approximately 75.9% and 36.5% of patients respectively. The ideal patient should be below 40years old, with a preoperative Tönnis grade of 0 or 1. Intraoperative fluoroscopy is able to guide a better precision when re-orientating the acetabulum.

LEVEL OF EVIDENCE

IV; systematic review and meta-analysis.

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

BACKGROUND

Some patients with developmental dysplasia of the hip (DDH) complained of anterior knee pain (AKP) before and after Bernese periacetabular osteotomy (PAO) surgery. The purpose of this study was to (1) identify the characteristics of patellofemoral joint (PFJ) deformities in patients with DDH and (2) to determine the effects of PAO on the PFJ.

METHODS

Seventy patients (86 hips) were included in the DDH group. Thirty-three patients (33 knees) without AKP and hip pain were included in the control group. All patients underwent simultaneous CT scans of the hip and knee joints before PAO and after hardware removal surgery. The distance from the anterior inferior iliac spine to the ilioischial line (DAI), was measured in DDH patients. Imaging parameters of knees, including the sulcus angle (SA), femoral trochlear depth (FTD), patellar width (PW), tibial tuberosity-trochlear groove (TT-TG), patellar tilt angle (PTA) and lateral shift of the patella (LSP) were measured in patients in both the DDH and control group. TT-TG, PTA, and LSP of DDH patients were measured before PAO and after hardware removal. The DAI, PTA, LSP and TT-TG of all DDH patients before and after Bernese PAO were compared using paired t-tests. The FTD, PW, and SA of the DDH patients and the control group were analyzed using independent t-tests. PTA, TT-TG, and LSP between the control group and preoperative DDH patients, between the control group and post PAO patients were compared using independent t-tests.

RESULTS

The DAI changed from 4.04 ± 0.61 mm before PAO surgery to 5.44 ± 0.63 mm after PAO surgery. The SA of the DDH group (140.69 ± 11.30 degree) was greater than that of the control group (130.82 ± 6.43 degree). The FTD and the PW of the DDH group (5.45 ± 1.59 mm, 4.16 ± 0.36 mm) were smaller than that of the control group (7.39 ± 1.20 mm, 4.24 ± 0.38 mm). The changes in LSP, PTA, and TT-TG before and after surgery were not statistically significant. Both before and after PAO, there was no statistically significant difference in the parameters of LSP, PTA, and TT-TG compared with the control group.

CONCLUSION

The knee joints of DDH patients presented a certain degree of femur trochlear groove dysplasia and patellofemoral instability. PAO surgery did not change PFJ stability, although the origination point of the rectus femoris muscle moved laterally during PAO surgery.

Recurrent Post-traumatic Posterior Hip Dislocation Treated Using a Bone Block Technique: Case Report and a Review of the Literature

CASE

A 26-year-old man presented with recurrent native hip dislocation after an initially traumatic posterior right hip dislocation. The combined soft-tissue and bony deficiency was addressed using an autologous bone block technique, as previously popularized for shoulder instability. Thirteen years postoperatively, no subsequent dislocations occurred, and the patient has an excellent functional outcome.

CONCLUSION

The bone block technique for hip stabilization can be used to address focal acetabular deficiencies with promising long-term follow-up.

Highly Cited Articles in Periacetabular Osteotomy Research

Purpose

The aim of this study is to identify highly cited articles and examine trends and characteristics in research on periacetabular osteotomy.

Materials and Methods

The 50 most highly cited articles on periacetabular osteotomy research were identified using Scopus. Data regarding article demographics and publication were collected from each article and an analysis was performed.

Results

The mean citation count was 125±37. The article with the highest total citation count (796), five-year citation count (327), and five-year citation density (65/year) was reported by Reinhold Ganz. The five-year citation density showed strong correlation with total citation density (r=0.930, P<0.001). Reinhold Ganz, the most productive author, was listed on 13 articles in the cohort with 455 weighted citation points.

Conclusion

This study provides a collection of articles examining periacetabular osteotomies and demonstrates that citation count can be regarded as an acceptable measure of the contemporary academic influence of an article.

Mobility-related outcomes for periacetabular osteotomy in persons with acetabular dysplasia: setting the stage for measurement of real-world outcomes

Periacetabular osteotomy (PAO) is a surgery for persons with symptomatic acetabular dysplasia (AD) that increases acetabular coverage of the femoral head for reducing hip pain and improving function. Patient-reported outcomes (PROs) are significantly improved following PAO, yet little is known regarding mobility-related outcomes. This narrative review provides a synthesis of evidence regarding PROs and mobility-related outcomes in persons with AD following PAO. We further identified important future research directions, chiefly the need for measurement of real-world outcomes. We searched PubMed using comprehensive predefined search terms. We included studies that (i) enrolled persons with AD undergoing PAO, (ii) included PROs and/or mobility-related outcomes and (iii) were written in English. We synthesized and summarized study characteristics and findings. Twenty-three studies were included in this review. Commonly evaluated PROs included pain (n = 14), hip function (n = 19) and quality of life (n = 9). Mobility-related outcomes included self-reported physical activity (PA; n = 11), walking speed and cadence (n = 4), device-measured PA (n = 2), and sit-to-stand, four-square-step and timed stair ascent tests (n = 1). Persons with AD had significant improvements in PROs following PAO, yet mobility-related outcomes (e.g. walking speed and device-measured PA levels) did not change over 1 year following PAO. Few studies have evaluated mobility-related outcomes following PAO, and these studies were of a low methodological quality. Future research might include experience sampling data collection approaches and body-worn devices as free-living, technology-driven methodologies to evaluate mobility and other outcomes in persons with AD undergoing PAO.

[Recent research progress of hip-preserving treatment for adolescents and adults with developmental dysplasia of the hip]

Objective

To review the imaging evaluation, treatment progress, and controversy related to developmental dysplasia of the hip (DDH) in adolescents and adults.

Methods

The domestic and abroad hot issues related to adolescents and adults with DDH in recent years, including new imaging techniques for assessing cartilage, controversies over the diagnosis and treatment of borderline DDH (BDDH), and the improvement and prospect of peracetabular osteotomy (PAO) were summarized and analyzed.

Results

DDH is one of the main factors leading to hip osteoarthritis. As the understanding of the pathological changes of DDH continues to deepen, the use of delayed gadolinium-enhanced MRI of cartilage can further evaluate the progress of osteoarthritis and predict the prognosis after hip preservation. There are still controversies about the diagnosis and treatment of BDDH. At the same time, PAO technology and concepts are still being improved.

Conclusion

Cartilage injury and bony structure determine the choice of surgical methods and postoperative prognosis of hip preservation surgery. The hip preservation of adolescent and adult DDH patients will move towards the goal of individualization and accuracy.

Periacetabular osteotomy for acetabular retroversion: A systematic review and meta-analysis

INTRODUCTION

The evidence for periacetabular osteotomy (PAO) when used in the management of acetabular retroversion remain limited. The review aims to answer the following questions: (1) What are the indications for an anteverting PAO for acetabular retroversion? (2) When are other concomitant procedures required when performing anteverting PAO for acetabular retroversion? (3) To what extent is an anteverting PAO able to correct acetabular retroversion? (4) What are the clinical outcomes for an anteverting PAO when used in acetabular retroversion? (5) What is the estimated survival for anteverting PAO when used in the treatment of acetabular retroversion, before other procedures need to be performed? (6) What are the complications and the complication rates when an anteverting PAO is performed? (7) How do the outcomes of an anteverting PAO compare to other surgical procedures used in the management of acetabular retroversion?

MATERIAL AND METHODS

The systematic review was conducted using the PRISMA guidelines. The search was conducted using PubMed Medical Literature Analysis and Retrieval System Online (MEDLINE) and Cumulative Index to Nursing and Allied Health Literature (CINAHL) from inception through 1 May 2020. The keywords used were "periacetabular osteotomy". All studies that reported the outcomes of periacetabular osteotomy for acetabular retroversion were included. Each study's data was then retrieved individually. The study design, surgical technique, indications, outcomes and complications of each study were analysed.

RESULTS

Seven studies with 225 hips were included. The pooled odds ratio (OR) for a positive crossover sign and posterior wall sign preoperatively as compared to postoperatively were 456.31 (95% CI: 99.57 to 2091.28) and 53.45 (95% CI: 23.05 to 123.93) respectively. The pooled weighted mean difference (WMD) for studies with their mean preoperative LCEA and AI in the dysplastic range were 12.61 (95% CI: 6.54 to 18.68) and-15.0 (95% CI: -19.40 to -11.80) respectively, while the pooled WMD for studies with their mean preoperative LCEA and AI in the normal range were 3.43 (95% CI: 1.08 to 5.77) and -3.56 (95% CI: -5.29 to -1.83) respectively. Other indicators for acetabular retroversion correction, hip dysplasia correction, functional outcomes and range of motion were also significantly improved and sustained up till 11 years postoperatively. Only 7.1% of the hips required subsequent surgical procedures for impingement symptoms or progression of osteoarthritis, and the mean estimate for survival time across the studies was 123.90 months (95% CI: 119.94 to 127.86). The complication rates for low-grade complication were 31.6% while the rate for high-grade complications was 12.0%.

DISCUSSION

Anteverting PAO is indicated for symptomatic acetabular retroversion, and when performed, leads to good deformity correction for both acetabular retroversion and hip dysplasia, positive improvement in clinical outcomes sustainable till 11 years postoperatively and a mean estimated survival time of more than 10 years.

LEVEL OF EVIDENCE

IV; Systematic review and meta-analysis.

Effect of COVID-19 pandemic on hip preservation surgery—a prospective surveillance from the UK Non-Arthroplasty Hip Registry

A multi-centre, registry-based cohort study was conducted to assess the effect of the coronavirus disease 2019 (COVID-19) pandemic on the provision of non-arthroplasty hip surgery (NAHS) in the UK by (i) comparing the number of NAHS performed during the pandemic to pre-pandemic levels, (ii) prospectively auditing compliance to established guidance and (iii) evaluating post-operative outcomes and their predictors. Patients who underwent NAHS during the pandemic/pre-pandemic were selected from the Non-Arthroplasty Hip Registry, which collects demographic, procedural and pre-operative outcome data. Patients during the pandemic period were emailed separate COVID-19 surveillance questionnaires, which evaluated adherence to guidelines and post-operative outcomes. Fisher’s exact tests and logistic regression were used to identify predictors for developing COVID-19 and being re-admitted into hospital, post-surgery. There was a 64% reduction of NAHS performed during the pandemic compared to the pre-pandemic period. Ninety-nine percent of participants self-isolated, and 96.8% received screening, pre-operatively. No participant was COVID-19-positive peri-operatively. Post-operatively, participants had an intensive care unit admission rate of 2%, median hospital stay of 1 day, hospital readmission rate of 4.2%, COVID-19 development rate of 2.3% and a thromboembolic complication rate of 0.32%. No COVID-19-positive patient developed adverse post-operative outcomes. Participants who developed COVID-19 post-operatively had greater odds of having undergone osteotomy in comparison to arthroscopic surgery (P = 0.036, odds ratio = 5.36). NAHS was performed with good compliance to established guidance, and adverse operative outcomes remained low. If guidance is followed, the risk of COVID-19 post-op development is low. Although bigger operations have a slightly higher risk, this does not impact their prognosis.

Novel Utilization of Anterior Intrapelvic (Stoppa) Approach for Periacetabular Ganz Osteotomy: A Report of 2 Cases

CASE

The Ganz periacetabular osteotomy (PAO) is widely used to correct developmental hip dysplasia in the adolescent and young adult population. The aim of this case study was to examine the novel utility and safety of Stoppa approach for the Ganz PAO in a 15-year-old girl and 25-year-old man. The Stoppa approach is traditionally used for acetabular fractures, and its use for a Ganz PAO is relatively novel.

CONCLUSION

The Stoppa approach allows surgeons to successfully perform the Ganz PAO while simultaneously providing direct visualization for all osteotomies and vital structures.

Bony landmarks, distances and their correlations to each other, which can be used during periacetabular osteotomy: a CT study performed on dysplastic hips

As a surgical technique for hip dysplasia, Bernese periacetabular osteotomy (PAO) still poses technical difficulties and unclear surgical steps like the depth of the first ‘ischial’ cut, the start of the iliac cut and the width of the retroacetabular cut to prevent either iatrogenic joint entrance or posterior column fracture. Twenty-seven dysplastic hips (CE < 25°) were randomly matched with nondysplastic hips (n: 27, CE > 25°). 3D CT sections of the hips were evaluated and the width of the ischium, the distance from the infra-acetabular groove to the ischial spine, from the anterior superior iliac spine (ASIS) to the joint or sciatic notch or the sciatic spine, from the most medial point at the acetabulum to the posterior column, ischial spine or sciatic notch were measured for each group and correlated. The distances (mm) from the infra-acetabular groove to the ischial spine (42 ± 4, 44 ± 4, P: 0.03), the anterior superior iliac spine to the joint (52 ± 6, 60 ± 3, P: 0.03), the most medial point at the acetabulum to the posterior column (34 ± 2, 36 ± 2, P: 0.005) were shorter in the dysplastic group. The distance from the ASIS to the sciatic notch was correlated with the distance from the infra-acetabular groove to the ischial spine, from the ASIS to the joint and the most medial point at the acetabulum to the posterior column. The distance from the ASIS to the sciatic notch can be used intraoperatively to guess the X-ray guided or blindly osteotomized stages to predict the width or depth of the osteotomy to prevent intraarticular extension or posterior column fracture.

[Mid-term effectiveness of periacetabular osteotomy through modified ilioinguinal approach for acetabular dysplasia in adults]

Objective

To investigate the mid-term effectiveness of periacetabular osteotomy (PAO) through modified ilioinguinal approach for acetabular dysplasia in adults.

Methods

Between January 2016 and December 2018, 39 patients (43 hips) with acetabular dysplasia who met the selection criteria were enrolled in the study and their clinical data were retrospectively analyzed. All patients were treated with PAO via modified ilioinguinal approach (firstly, the skin and superficial facia were cut via the traditional ilioinguinal approach, and the deep tissues were cut via the modified iliac-femoral approach). There were 3 males (3 hips) and 36 females (40 hips) with an average age of 36 years (range, 18-51 years). Among them, 35 cases of lesions involved single hip and 4 cases of lesions involved bilateral hips. The disease duration ranged from 4 to 96 months, with a median of 18 months. According to the modified Tönnis grading for osteoarthritis, 35 hips were classified as grade 0, 6 hips as grade Ⅰ, and 2 hips as grade Ⅱ. All patients had different degrees of hip pain. The preoperative visual analogue scale (VAS) score of pain was 4.7±0.8, and the modified Harris hip score was 78.5±8.6. The lateral centre-edge angle (LCEA) was (10.52±10.83)°, and the acetabular index (AI) was (26.89±9.07) °. The operation time, intraoperative blood loss, and the incidence of complications were recorded. LCEA, AI, and the progression of osteoarthritis were reviewed by X-ray films. The function and pain of hip joint were evaluated by modified Harris hip score and VAS score.

Results

All operations were successfully completed. The operation time was 90-150 minutes, with an average of 130 minutes. The volume of intraoperative blood loss was 350-600 mL, with an average of 500.6 mL. All patients were followed up 17-52 months, with an average of 32.7 months. Postoperative numbness of the lateral femoral cutaneous nerve occurred in 3 cases, and no other complications occurred. At last follow-up, the modified Harris hip score was 97.7±3.7 and VAS score was 0.9±1.1, both of which were better than those before operation ( P<0.05). At 1 year after operation, X-ray films showed that the all osteotomies healed. In term of the modified Tönnis grading for osteoarthritis, 1 hip downgraded from grade 1 to grade 0, while the remaining hips stayed unchanged. At last follow-up, LCEA and AI were (27.54±8.49) ° and (11.30±5.53) °, respectively, which were significantly different from those before operation ( P<0.05).

Conclusion

PAO through modified ilioinguinal approach is effective in relieving pain and restoring hip function in adults with acetabular dysplasia, which can overcome the disadvantages of the traditional ilioinguinal approach, and may delay the development of osteoarthritis.

Complications of hip preserving surgery

Preoperative evaluation of the pathomorphology is crucial for surgical planning, including radiographs as the basic modality and magnetic resonance imaging (MRI) and case-based additional imaging (e.g. 3D-CT, abduction views).

Hip arthroscopy (HAS) has undergone tremendous technical advances, an immense increase in use and the indications are getting wider. The most common indications for revision arthroscopy are labral tears and residual femoroacetabular impingement (FAI).

Treatment of borderline developmental dysplastic hip is currently a subject of controversy. It is paramount to understand the underlining problem of the individual hip and distinguish instability (dysplasia) from FAI, as the appropriate treatment for unstable hips is periacetabular osteotomy (PAO) and for FAI arthroscopic impingement surgery.

PAO with a concomitant cam resection is associated with a higher survival rate compared to PAO alone for the treatment of hip dysplasia. Further, the challenge for the surgeon is the balance between over- and undercorrection.

Femoral torsion abnormalities should be evaluated and evaluation of femoral rotational osteotomy for these patients should be incorporated to the treatment plan.

Cite this article: EFORT Open Rev 2021;6:472-486. DOI: 10.1302/2058-5241.6.210019

Incidence and clinical outcome of lateral femoral cutaneous nerve injury after periacetabular osteotomy

AIMS

Injury to the lateral femoral cutaneous nerve (LFCN) is one of the known complications after periacetabular osteotomy (PAO) performed using the anterior approach, reported to occur in between 1.5% and 65% of cases. In this study, we performed a prospective study on the incidence of LFCN injury as well as its clinical outcomes based on the Harris Hip Score (HHS), Short-Form 36 Health Survey (SF-36), and Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ).

METHODS

The study included 42 consecutive hips in 42 patients (three male and 39 female) who underwent PAO from May 2016 to July 2018. We prospectively evaluated the incidence of LFCN injury at ten days, three months, six months, and one year postoperatively. We also evaluated the clinical scores, including the HHS, SF-36, and JHEQ scores, at one year postoperatively.

RESULTS

LFCN injury was observed in 31 of 42 (74%) patients at ten days, of which 11 resolved completely by one year. Incidence decreased gradually, to 25 of 42 (60%) patients at three months, 24 of 42 patients (57%) at six months, and 20 of 42 (48%) patients at one year postoperatively. There was no significant difference in the HHS between patients with and without LFCN injury at one year postoperatively. Regarding the SF-36 and JHEQ, a significant difference in the mental score was recognized between patients with and without LFCN injury, but there were no significant differences in the other clinical scores.

CONCLUSION

The incidence of LFCN injury was 74% at ten days after PAO, and subsequently decreased to 48% at one year. LFCN injury did not influence the hip function as assessed by the HHS, but had a negative impact on mental health at one year. Cite this article: Bone Joint J 2021;103-B(4):659-664.

Comparison of the modified Smith-Petersen (S-P) and ilioinguinal (I-I) approaches for periacetabular osteotomy in adult developmental dysplasia of the hip: a retrospective study

Background

Adult developmental dysplasia of the hip is an untreated congenital hip dysplasia that results in adult hip pain. One of the usual and effective methods for the treatment of this condition is periacetabular osteotomy. However, which approach is better between the modified S-P and the I-I approaches is still unclear and controversial.

Method and materials

We retrospectively assessed our experience with the modified S-P and the I-I approaches by inquiring and evaluating intraoperative blood loss, postoperative radiographic material, postoperative function of the hip, and related complications from July 2014 to January 2019.

Results

A total of 61 patients with adult developmental dysplasia of the hip were enrolled, and 33 patients were divided into a modified S-P group and 28 patients were divided into I-I group. The operation time and blood loss of group I-I were higher than that of group modified S-P. Other clinical and radiographic indexes showed no statistical significance between group the modified S-P and I-I groups.

Conclusion

There is no significant difference in the improvement of the function of the hip at the post-operation stage, but group I-I may require more operation time and blood loss at the intra-operation stage.

A New Rectus and Sartorius Sparing Approach for Periacetabular Osteotomy in Patients with Developmental Dysplasia of the Hip

Background: periacetabular osteotomy (PAO) is known as the gold standard surgical treatment in young adults with symptomatic hip dysplasia. With the aim of reducing soft tissue trauma, we developed a new rectus and sartorius sparing (RASS) approach. We hypothesized that this new PAO technique was equal regarding acetabular reorientation, complication rate, and short-term clinical outcome parameters, compared to our conventional, rectus sparing (RS) approach. Patients and Methods: we retrospectively assessed all PAO procedures performed by a single surgeon between 2016 and 2019 (n = 239 hips in 217 patients). The cases in which the new RASS technique were used (n = 48) were compared to the RS cases for acetabular orientation parameters, surgical time, perioperative reduction of hemoglobin level, and length of hospital stay (LOHS). Inclusion criteria were a lateral center-edge angle (LCEA) <25° and osteoarthritis Tönnis grade ≤1. Patients with acetabular retroversion or additional femoral osteotomy were excluded. Results: the mean patient age at the time of surgery was 29 years (14 to 50, SD ± 8.5). Females accounted for 79.5% in this series. The mean preoperative LCEA were 16° (7 to 24°, SD ± 4.4) and 15° (0 to 23°, SD ± 6) in the RASS and the RS group, respectively (p = 0.96). The mean preoperative acetabular index (AI) angles were 14° (2 to 25°, SD ± 4) and 14° (7 to 29°, SD ± 4.3), respectively (p = 0.67). The mean postoperative LCEA were significantly improved to 31° (25 to 37°, SD ± 3.5, p < 0.001) and 30.2° (20 to 38°, SD ± 4, p < 0.001), respectively. The mean postoperative AI angles improved to 2.8° (−3 to 13°, SD ± 3.3, p < 0.001) and 3° (−2 to 15°, SD ± 3.3, p < 0.001), respectively. There were no significant differences between the RASS and the RS group for surgical time, perioperative reduction in hemoglobin level, and LOHS. No blood transfusions were necessary perioperatively in either group. No major perioperative complication occurred in either group. We observed one surgical site infection (SSI) requiring superficial debridement in the RS group. Conclusion: the RASS approach for PAO showed to be a safe procedure with equivalent acetabular reorientation and equivalent clinical outcome parameters compared to the RS approach. Additionally, patients have fewer postoperative restrictions in mobilization with the RASS approach.

Augmented Reality Based Surgical Navigation of Complex Pelvic Osteotomies—A Feasibility Study on Cadavers

Augmented reality (AR)-based surgical navigation may offer new possibilities for safe and accurate surgical execution of complex osteotomies. In this study we investigated the feasibility of navigating the periacetabular osteotomy of Ganz (PAO), known as one of the most complex orthopedic interventions, on two cadaveric pelves under realistic operating room conditions. Preoperative planning was conducted on computed tomography (CT)-reconstructed 3D models using an in-house developed software, which allowed creating cutting plane objects for planning of the osteotomies and reorientation of the acetabular fragment. An AR application was developed comprising point-based registration, motion compensation and guidance for osteotomies as well as fragment reorientation. Navigation accuracy was evaluated on CT-reconstructed 3D models, resulting in an error of 10.8 mm for osteotomy starting points and 5.4° for osteotomy directions. The reorientation errors were 6.7°, 7.0° and 0.9° for the x-, y- and z-axis, respectively. Average postoperative error of LCE angle was 4.5°. Our study demonstrated that the AR-based execution of complex osteotomies is feasible. Fragment realignment navigation needs further improvement, although it is more accurate than the state of the art in PAO surgery.

Computer assistance in hip preservation surgery-current status and introduction of our system

INTRODUCTION

Preservation surgery of the hip with open or arthroscopic approach has always been challenging as complex 3-D anatomy and limited surgical access make intraoperative evaluation difficult. Recent advances in computer technology offer a wide range of innovative solutions with a goal to improve accuracy and safety of corrective procedures on human joints.

METHOD

The author critically reviews currently available literature in the field of computer assistance in hip preservation surgery. Basic features of unique planning software and navigation surgical system used in treatment of femoroacetabular impingement and hip dysplasia are introduced.

RESULTS

Currently available software provides preoperative identification of hip deformity on CT-based 3-D model and planning of the surgical correction using kinematic protocols. Real-time intraoperative 3-D orientation is possible, and execution of surgical correction can be performed either with navigation of surgical tools or with printed templates. Computer assistance in hip preservation surgery is in the developing phase. First clinical experiences of its use in treatment of femoroacetabular impingement, hip dysplasia, hip tumors, and avascular necrosis of the femoral head are promising.

CONCLUSION

Computer assistance has been applied for treatment of several hip disorders. Technical advances are suggested and quality basic studies and clinical trials are encouraged for the novel technology to become more user friendly and widely accepted.