Agreement of radiographic measurements and patient-reported outcome in 61 patients with Legg-Calvé-Perthes disease at mean follow-up of 28 years

Adherence to Wide-Abduction Brace Treatment is Associated With Improved Hip Abduction and Radiographic Outcomes in Legg-Calvé-Perthes Disease

INTRODUCTION

The wide-abduction A-frame brace contains the femoral head to improve its remodeling in Legg-Calvé-Perthes disease (LCPD). There is no study of the effect of brace adherence on hip outcomes. The purpose of this study was to determine if patient adherence to A-frame brace treatment is associated with improved hip abduction range of motion and radiographic outcomes in children with LCPD.

METHODS

This retrospective study included patients aged 4 to 11 years with LCPD treated with an A-frame brace. Patients aged >11 and those treated with osteotomy before completing brace treatment were excluded. Built-in temperature sensors measured brace wear. Hip abduction was measured on examination before and after bracing. Deformity index (DI) and sphericity deviation score (SDS) were measured from radiographs at the 2-year follow-up and healed stage, respectively. Pearson correlation and multiple regression analyses were performed.

RESULTS

Fifty-seven patients (44 male; 77%) were included with a mean age of 7.0±1.6 at brace treatment and mean adherence of 0.66±0.28. Brace adherence was associated with increased hip abduction (R=0.36; P=0.006) and decreased DI (R=-0.37; P=0.042) across all patients, and decreased SDS in patients <9 years old at the time of brace treatment (R=-0.58; P=0.024). A +0.50 increase in adherence was associated with +9.4° hip abduction (P=0.018), -0.13 DI (P=0.027), and -17.7 SDS (P=0.019).

CONCLUSIONS

Adherence to A-frame brace treatment was associated with increased hip abduction, decreased femoral head deformity, and increased sphericity. Patients and parents can be counseled regarding brace adherence to maximize outcomes of treatment.

LEVEL OF EVIDENCE

III-Therapeutic Study.

Demographics and risk for containment surgery in patients with unilateral Legg-Calvé-Perthes disease: a national population-based cohort study of 309 patients from the Swedish Pediatric Orthopedic Quality Register

BACKGROUND AND PURPOSE

It is controversial as to which patients affected by Legg-Calvé-Perthes disease (LCPD) benefit from containment surgery. This population-based study based on data from a national quality registry aims to assess the incidence of LCPD and to explore which factors affect the decision for surgical intervention.

METHODS

This observational study involved 309 patients with unilateral LCPD reported between 2015 and 2023 to the Swedish Pediatric Orthopedic Quality Register (SPOQ). Descriptive statistics and logistic regression models were used for analysis.

RESULTS

In 2019, the assessed incidence of LCPD in the Swedish population of 2-12-year-olds was 4.2 per 105. 238 (77%) were boys with a mean age of 6 years. At diagnosis, 55 (30%) were overweight or obese, rising to 17 patients (39%) and 16 patients (40%) at 2-year follow-up for surgically and non-surgically treated groups, respectively. At diagnosis, affected hips had reduced abduction compared with healthy hips, and their abduction remained restricted at the 2-year follow-up. Surgically treated patients had inferior abduction compared with non-surgically treated ones at diagnosis. The adjusted risk for containment surgery increased with age and in the presence of a positive Trendelenburg sign but decreased with greater hip abduction.

CONCLUSION

We found a lower national yearly incidence (4.2 per 105) than previously reported in Swedish studies. A higher proportion of overweight or obese patients compared with the general Swedish population of 4-9-year-olds was identified. Increasing age, positive Trendelenburg sign, and limited hip abduction at diagnosis correlated with increased surgical intervention likelihood.

Ganz femoral head reduction associated with coverage and containment procedures improve radiological and functional outcomes in Perthes' disease

Aims

Ganz's studies made it possible to address joint deformities on both the femoral and acetabular side brought about by Perthes' disease. Femoral head reduction osteotomy (FHRO) was developed to improve joint congruency, along with periacetabular osteotomy (PAO), which may enhance coverage and containment. The purpose of this study is to show the clinical and morphological outcomes of the technique and the use of an implemented planning approach.

Methods

From September 2015 to December 2021, 13 FHROs were performed on 11 patients for Perthes' disease in two centres. Of these, 11 hips had an associated PAO. A specific CT- and MRI-based protocol for virtual simulation of the corrections was developed. Outcomes were assessed with radiological parameters (sphericity index, extrusion index, integrity of the Shenton's line, lateral centre-edge angle (LCEA), Tönnis angle), and clinical parameters (range of motion, visual analogue scale (VAS) for pain, Merle d'Aubigné-Postel score, modified Harris Hip Score (mHHS), and EuroQol five-dimension five-level health questionnaire (EQ-5D-5L)). Early and late complications were reported.

Results

The mean follow-up was 39.7 months (standard deviation (SD) 26.4). The mean age at surgery was 11.4 years (SD 1.6). No major complications were recorded. One patient required a total hip arthroplasty. Mean femoral head sphericity increased from 46.8% (SD 9.34%) to 70.2% (SD 15.44; p < 0.001); mean LCEA from 19.2° (SD 9.03°) to 44° (SD 10.27°; p < 0.001); mean extrusion index from 37.8 (SD 8.70) to 7.5 (SD 9.28; p < 0.001); and mean Tönnis angle from 16.5° (SD 12.35°) to 4.8° (SD 4.05°; p = 0.100). The mean VAS improved from 3.55 (SD 3.05) to 1.22 (1.72; p = 0.06); mean Merle d'Aubigné-Postel score from 14.55 (SD 1.74) to 16 (SD 1.6; p = 0.01); and mean mHHS from 60.6 (SD 18.06) to 81 (SD 6.63; p = 0.021). The EQ-5D-5L also showed significant improvements.

Conclusion

FHRO associated with periacetabular procedures is a safe technique that showed improved functional, clinical, and morphological outcomes in Perthes' disease. The newly introduced simulation and planning algorithm may help to further refine the technique.

Epidemiology, natural evolution, pathogenesis, clinical spectrum, and management of Legg-Calvé-Perthes

Background

Legg-Calvé-Perthes disease is a self-limiting disorder that develops in children following interruption of the blood supply to the capital femoral epiphysis. This review outlines the current knowledge on the epidemiology, natural evolution, clinical spectrum, and management of the disease.

Methods

The literature pertaining to these aspects of the disease were studied and summarized in this review.

Results

Epidemiological studies suggest that environmental factors contribute to the causation of the disease. Incidence rates monitored over time indicate that the incidence of Legg-Calvé-Perthes disease is declining. The natural evolution followed on sequential plain radiographs enables division of the disease into Stages Ia, Ib, IIa, IIb, IIIa, IIIb, and IV. Reversible deformation of the capital occurs in Stages Ia-IIa simply on standing while irreversible deformation may occur in Stages IIb and IIIa. Treatment of Legg-Calvé-Perthes disease in Stages Ia-IIa aims to prevent the femoral head from getting deformed by containment and avoidance of weight-bearing. In Stages IIb and IIIa, treatment aims to remedy the effects of early irreversible deformation of the femoral head. In Stage IIIb and IV, treatment is directed to correcting the altered shape of the femoral head. The impression that these treatment methods are helpful is based on poor quality evidence.

Conclusion

There is an urgent need to undertake Level I studies to establish the efficacy of currently treatment.

Level of evidence

level V.

Radiological hip shape and patient-reported outcome measures in healed Perthes' disease

Aims

This study aimed to evaluate the relationship between hip shape and mid-term function in Perthes' disease. It also explored whether the modified three-group Stulberg classification can offer similar prognostic information to the five-group system.

Methods

A total of 136 individuals aged 12 years or older who had Perthes' disease in childhood completed the Patient-Reported Outcomes Measurement Information System (PROMIS) Mobility score (function), Nonarthritic Hip Score (NAHS) (function), EuroQol five-dimension five-level questionnaire (EQ-5D-5L) score (quality of life), and the numeric rating scale for pain (NRS). The Stulberg class of the participants' hip radiographs were evaluated by three fellowship-trained paediatric orthopaedic surgeons. Hip shape and Stulberg class were compared to PROM scores.

Results

A spherical hip was associated with the highest function and quality of life, and lowest pain. Conversely, aspherical hips exhibited the lowest functional scores and highest pain. The association between worsening Stulberg class (i.e. greater deviation from sphericity) and worse outcome persisted after adjustment for age and sex in relation to PROMIS (predicted mean difference -1.77 (95% confidence interval (CI) -2.70 to -0.83)), NAHS (-5.68 (95% CI -8.45 to -2.90)), and NRS (0.61 (95% CI 0.14 to 1.08)), but not EQ-5D-5L (-0.03 (95% CI -0.72 to 0.11)).

Conclusion

Patient-reported outcomes identify lower function, quality of life, and higher pain in aspherical hips. The magnitude of symptoms deteriorated with time. Hip sphericity (i.e. the modified three-group classification of spherical, oval, and aspherical) appeared to offer similar levels of detail to the five-group Stulberg classification.

Does the Deformity Index Reliably Predict the Shape of the Femoral Head at Healing of Legg-Calvé-Perthes Disease?

BACKGROUND

Treatment of Legg-Calvé-Perthes disease (LCPD) aims to preserve the spherical shape of the femoral head. The deformity index (DI) <0.3, measured 2 years from disease onset, is a surrogate measure that predicts that the femoral head will be Stulberg class I or II at skeletal maturity. There is no study that compares the predictive value of DI against a quantitative measure of the shape of the femoral head when the disease heals. We undertook this study to assess the reproducibility of a new method of measurement of DI and see if DI could predict the shape of the femoral head when the disease healed.

METHODS

DI was measured 2 years after disease onset and the Sphericity Deviation Score (SDS) was measured at healing of LCPD on radiographs of 43 children. Reproducibility of measurement was tested. Each healed femoral head was classified as spherical or aspherical based on subjective visual assessment. The DI values were compared with SDS values.

RESULTS

The reproducibility of measurement of SDS was excellent and superior to that of DI. The mean duration of disease was 3.97±0.96 years. Only 17 of 32 hips with DI values <0.3 at 2 years had spherical femoral heads at healing (SDS <10). Three hips with SDS values <10 had DI values >0.3. The positive and negative predictive values of a DI <0.3 in predicting if the femoral head will be spherical (SDS <10) when the disease healed were 53% and 73%, respectively.

CONCLUSION

Though DI can be reproducibly measured the predictive value of a DI <0.3, to accurately identify hips that are likely to heal with spherical femoral heads, is not sufficiently high to justify its use as an outcome measure.