Outcome of peri-acetabular osteotomy for hip dysplasia in teenagers

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.

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.

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.

Leg Length Change After Curved Periacetabular Osteotomy and Its Impact on the Clinical Outcomes

BACKGROUND

Curved periacetabular osteotomy (CPO) is one of the periacetabular osteotomies for the treatment of acetabular dysplasia. Several complications have been described after CPO, however, there have been no reports on the leg length change (LLC). This study aimed to investigate the LLC after CPO and its impact on the clinical outcomes.

METHODS

This study was a retrospective review of 70 consecutive hips in 67 patients with symptomatic acetabular dysplasia who underwent CPO between March 2016 and April 2019. Preoperative and postoperative leg lengths were measured using anteroposterior radiographs, and the clinical outcomes were evaluated based on the Harris hip score (HHS) and Medical Outcomes Survey 36-item Short Form Health Survey (SF-36).

RESULTS

The mean LLC (and standard deviation) after CPO was -0.08 ± 3.10 mm. The mean HHS significantly improved from 73.5 points to 91.9 points (P < .001). The physical component and role component scores of SF-36 significantly improved from 35.1 to 46.1 (P < .001) and from 39.5 to 47.0 (P < .001), respectively. No significant differences were found between the preoperative and postoperative mental component scores of SF-36. In addition, among 70 hips, 35 hips exhibited leg length elongation (0 to plus 6.82 mm) after CPO, whereas 35 hips exhibited leg length shortening (0 to minus 6.23 mm). No significant differences were found in HHS and SF-36 between the leg elongation group and leg shortening group.

CONCLUSION

The mean LLC after CPO was -0.08 ± 3.10 mm, and this change does not affect the postoperative clinical outcomes.

Magnetic Resonance Imaging Assessment of Abductor Muscles Shortly After Curved Periacetabular Osteotomy

BACKGROUND

Curved periacetabular osteotomy (CPO) is performed via an anterior approach without detachment of the hip abductor muscles. This study aimed to evaluate the abductor muscle status shortly after CPO on magnetic resonance imaging (MRI).

METHODS

We prospectively evaluated 38 hips in 38 patients 1 week and 3 months after CPO between October 2017 and July 2019. The status of the abductor muscles was assessed on MRI using the following criteria: grade 0, normal; grade I, strain/edema; grade II, partial tear; and grade III, complete tear. We also evaluated associations between muscle status and patients' characteristics.

RESULTS

One week after CPO, the gluteus maximus was classified as grade 0 in all patients. The gluteus medius was grade 0 in 84.2% of patients and grade I in 15.8%. The gluteus minimus was grade I in 55.3% of patients and grade II in 44.7%. Three months after CPO, both the gluteus maximus and gluteus medius were grade 0 in all patients, while the gluteus minimus was still grade I in 47.4%. There were no significant differences between patients with a grade 0 and grade I gluteus minimus at 3 months after CPO in patients' characteristics (age and body mass index) or clinical scores (Harris Hip Score and Japanese Orthopedics Association score).

CONCLUSION

Both the gluteus minimus and medius showed abnormal appearances on MRI 1 week after CPO, whereas only the gluteus minimus showed abnormalities 3 months after CPO. This abductor muscle status did not affect the postoperative Harris Hip Score or Japanese Orthopedics Association score.

Is Hip Arthroscopy Effective in Patients With Combined Excessive Femoral Anteversion and Borderline Dysplasia? A Match-Controlled Study

BACKGROUND

Appropriate patient selection is critical when hip arthroscopy is considered in the setting of borderline dysplasia (BD). It is presumable that excessive femoral anteversion (EFA) and BD may contraindicate arthroscopy.

HYPOTHESIS

Patients with combined EFA and BD (EFABD) demonstrate significantly inferior short-term outcomes after arthroscopic labral preservation and capsular closure when compared with a similar control group with normal lateral coverage and femoral anteversion.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected and retrospectively reviewed on patients undergoing hip arthroscopy between April 2010 and November 2014. The EFABD group's inclusion criteria were BD (lateral center-edge angle, 18°-25°), labral tear, capsular closure, and femoral version ≥20°, as well as preoperative modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score-Sports Specific Subscale, and visual analog scale. Exclusion criteria were workers' compensation, preoperative Tönnis grade >1, microfracture, abductor pathology, or previous ipsilateral hip surgery or conditions. Patients in the EFABD group were matched 1:2 to a similar control group with normal coverage and femoral anteversion by age at surgery ± 6 years, sex, body mass index ± 5, acetabular Outerbridge grade (0, 1 vs 2, 3, 4), and iliopsoas fractional lengthening.

RESULTS

Sixteen EFABD cases were eligible for inclusion, and 100% follow-up was obtained at ≥2 years postoperatively. Twelve EFABD cases were matched to 24 control cases. Mean femoral version was 22.4° in the EFABD group and 10.2° in the control group ( P = .01). Mean lateral center-edge angle was 22.1° in the EFABD group and 31.5° in the control group ( P < .0001). Acetabuloplasty was performed significantly more frequently in the control group ( P = .0006). No other significant differences were found regarding demographics, findings, procedures, or preoperative scores. At latest follow-up, the EFABD group demonstrated significantly lower mean modified Harris Hip Score (76.1 vs 85.9; P = .005), Nonarthritic Hip Score (74.8 vs 88.5; P < .0001), Hip Outcome Score-Sports Specific Subscale (58.3 vs 78.4; P = .02), and patient satisfaction (7.1 vs 8.3; P = .005). There were 4 secondary surgical procedures (33.3%) in the EFABD group and 1 (4.2%) in the control group ( P = .03). One patient in each group required arthroplasty.

CONCLUSION

Patients treated with arthroscopic labral preservation and capsular closure in the setting of EFABD demonstrated significant improvements from presurgery to latest follow-up. However, their results are significantly inferior when compared with a matched-controlled group. Consideration of periacetabular osteotomy or femoral osteotomy may be warranted in the setting of EFABD to achieve optimal benefit.

Can Salter osteotomy correct late diagnosed hip dysplasia: A retrospective evaluation of 49 hips after 6.7 years?

BACKGROUND

Surgical treatment of late diagnosed development dysplasia of the hip (DDH) remains challenging with several methods being described. We therefore retrospectively evaluated the outcome of Salter innominate osteotomy (SIO) in patients with fully-grown bone, to evaluate whether this surgical procedure allows sufficient acetabular correction.

MATERIAL AND METHODS

Between 2004-2012 SIO had been performed in 45 patients (49 hips) with late diagnosed DDH. The evaluation included pre- and postoperative radiographs (n=49), the complication rate (n=49) and the clinical outcome (WOMAC, HHS, UCLA) (n=34).

RESULTS

Mean age at surgery was 27.6 (16-51) with a follow-up of 6.7±2.7 (0.9-11.0) years. Radiologically, a good acetabular correction with a significant improvement of the Center Edge angle (15.4° to 34.9°), sharps angle (45.7° to 32.0°) and migration percentage (33.2% to 14.4%) (p<0.001) was found. Clinical results revealed a WOMAC of 13.9±13.3, UCLA of 7.8±2.1 and HHS of 85.0±11.8. Complications were noted for 10 patients (20%) with 7 (14%) requiring revision.

CONCLUSION

The results demonstrated that SIO achieved a satisfying acetabular correction and good clinical results in late diagnosed DDH. It therefore might be an option in some cases, although periacetabular osteotomy techniques are currently preferable used as they allow a wider range of acetabular correction.

LEVEL OF EVIDENCE

IV, retrospective observational study.

Long-term results of a modified Spitzy shelf operation for residual hip dysplasia and subluxation. A fifty year follow-up study of fifty six children and young adults

PURPOSE

The purposes of this study were to establish long-term outcome of the Spitzy shelf-operation and evaluate whether the procedure would delay osteoarthritis.

METHODS

During 1954-1976, 56 patients (70 hips) underwent Spitzy shelf operation at a mean age of 11.9 years (5 to 22). Indications included residual hip dysplasia or subluxation with Centre-Edge angle < 20°. We used survival analysis with conversion to total hip replacements as end-point. For patients without total hip replacement, information was provided from case records and radiographs. Avascular necrosis was assessed in pre-Spitzy radiographs, when available. Kaplan-Meier product-limit method was used to estimate survival function of the Spitzy shelf operation. Survival was assessed by Cox regression. Univariable Cox regression was performed separately for each variable. Potential predictors (p-value < 0.10) were entered into a multivariable regression model; p-value < 0.05 was considered significant.

RESULTS

Mean survival of the shelf procedure was 39.9 years (21 to 53). Survival fell from 83 % 30 years post-operatively, to 22 % at 50 years. Fifty-three hips (76 %) had undergone total hip replacement at mean age of 49.4 years (33 to 64). Seventeen hips had not received total hip replacement, mean survival 47.9 years (39 to 53).

CONCLUSION

The study showed that Spitzy shelf-operation had satisfactory long-term outcome with hip-survival in almost 90 % at patient age 40 years. The results indicate that Spitzy shelf-operation postpone total hip replacement. We consider Spitzy shelf-operation a good alternative in patients above 8 years. In younger children the procedure is not recommended due to increased frequency of graft resorption.

Curtain osteophytes are one of the risk factors for the poor outcome of rotational acetabular osteotomy

PURPOSE

Rotational acetabular osteotomy (RAO) is one of the surgical procedures for painful dysplastic hips. Although several risk factors for poor outcome of RAO have been reported, the presence of a curtain osteophyte in the acetabulum has not been evaluated as a possible risk factor. This study aimed to analyze the risk factors affecting the outcome of RAO and to clarify whether curtain osteophytes are one of the risk factors.

METHODS

We retrospectively analyzed 87 hips in 78 patients with a mean age of 36 (range, 13-54) years. The mean follow-up period was 8.3 (range, 2.1-19.5) years. The radiographic severity of osteoarthritis was classified into four stages: pre-arthrosis, initial stage, advanced stage, and terminal stage. The Japanese Orthopaedic Association (JOA) hip score was used for clinical evaluation. Poor outcome was defined as a hip with a JOA score < 80 points or terminal-stage osteoarthritis at final follow-up. Several factors were evaluated by logistic regression analysis.

RESULTS

At final follow-up, ten hips had a JOA score < 80 and nine hips had progressed to terminal-stage osteoarthritis. Since five hips had a JOA score < 80 as well as terminal-stage osteoarthritis, a total of 14 hips were determined to have poor outcome. An additional ten years of age at surgery, pre-operative minimal joint space < 2 mm, presence of a curtain osteophyte, and fair/poor congruency in abduction were identified as significant risk factors for poor outcome of RAO.

CONCLUSIONS

Hips with curtain osteophyte should be evaluated carefully before RAO.