Part-time Abduction Bracing in Infants With Residual Acetabular Dysplasia: Does Compliance Monitoring Support a Dose-dependent Relationship?

Does brace treatment following closed reduction of developmental dysplasia of the hip improve acetabular coverage?

Aims

Abduction bracing is commonly used to treat developmental dysplasia of the hip (DDH) following closed reduction and spica casting, with little evidence to support or refute this practice. The purpose of this study was to determine the efficacy of abduction bracing after closed reduction in improving acetabular index (AI) and reducing secondary surgery for residual hip dysplasia.

Methods

We performed a retrospective review of patients treated with closed reduction for DDH at a single tertiary referral centre. Demographic data were obtained including severity of dislocation based on the International Hip Dysplasia Institute (IHDI) classification, age at reduction, and casting duration. Patients were prescribed no abduction bracing, part-time, or full-time wear post-reduction and casting. AI measurements were obtained immediately upon cast removal and from two- and four-year follow-up radiographs.

Results

A total of 243 hips underwent closed reduction and 82% (199/243) were treated with abduction bracing. There was no difference between those treated with or without bracing with regard to sex, age at reduction, severity of dislocation, spica duration, or immediate post-casting AI (all p > 0.05). There was no difference in hips treated with or without abduction brace with regard to AI at two years post-reduction (32.4° (SD 5.3°) vs 30.9° (SD 4.6°), respectively; p = 0.099) or at four years post-reduction (26.4° (SD 5.2°) vs 25.4° (SD 5.1°), respectively; p = 0.231). Multivariate analysis revealed only IHDI grade predicted AI at two years post-reduction (p = 0.004). There was no difference in overall rate of secondary surgery for residual dysplasia between hips treated with or without bracing (32% vs 39%, respectively; p = 0.372). However, there was an increased risk of early secondary surgery (< two years post-reduction) in the non-braced group (11.4% vs 2.5%; p = 0.019).

Conclusion

Abduction bracing following closed reduction for DDH treatment is not associated with decreased residual dysplasia at two or four years post-reduction but may reduce rates of early secondary surgery. A prospective study is indicated to provide more definitive recommendations.

Abduction Bracing Following Anterior Open Reduction for Developmental Dysplasia of the Hip Does Not Improve Residual Dysplasia or Reduce Secondary Surgery

BACKGROUND

Abduction bracing is commonly used following open reduction and spica casting of developmental dysplasia of the hip. However, there is little evidence to support or refute this practice that carries associated cost and burden for families. The purpose of this study was to determine the efficacy of abduction bracing after open reduction in improving the acetabular dysplasia and reducing the rate of secondary surgery for residual dysplasia.

METHODS

This is a retrospective study of patients treated with open reduction at a single tertiary referral center. Demographic data, severity of dislocation [International Hip Dysplasia Institute (IHDI) class], age at reduction, and casting duration were obtained. Patients were prescribed no bracing, part-time (≤18 h/d), or full-time (≥20 h/d) brace wear based on surgeon preference. Acetabular index (AI) measurements were obtained at cast removal and at 2- and 4-year follow-up.

RESULTS

A total of 146 hips underwent open reduction with 61% (89/146) of hips treated with abduction bracing. There was no difference between braced and nonbraced cohorts with regards to sex, age at time of reduction, dislocation severity, cast duration, immediate postcasting AI, or incidence of medial open reduction. There was no difference in hips treated with or without brace following open reduction with regards to AI at 2 years postreduction (31.8±6.7 vs. 30.4±6.1 degrees, P =0.27) or at 4 years postreduction (24.9±6.5 vs. 24.7±6.5 degrees, P =0.97). However, further analysis showed lower mean AI at 2-year follow-up for braced versus nonbraced patients following medial open reduction (30.0±5.7 vs. 34.5±7.0 degrees, P =0.02). This difference was no longer present at 4-year follow-up (26.6±6.8 vs. 24.2±6.6 degrees, P =0.44). However, 4/19 (21%) nonbraced hips underwent secondary surgery for residual dysplasia and were consequently excluded from the AI measurement at 4 years postreduction (compared with 4/39 [10%] braced hips within the same time period). There was no difference in the rate of secondary surgery between braced and nonbraced hips (30% vs. 33%, respectively, P =0.70). Multivariate analysis demonstrated that neither IHDI classification, bracing, nor age at reduction predicted residual dysplasia.

CONCLUSIONS

Abduction bracing following anterior open reduction for developmental dysplasia of the hip is not associated with decreased residual dysplasia at 2/4 years postreduction or with decreased secondary surgery. These results suggest that abduction bracing following anterior open reduction may not provide clinical benefit. However, abduction bracing may be beneficial following medial open reduction. A prospective study is necessary to provide more definitive recommendations.

LEVEL OF EVIDENCE

Level III-therapeutic study.

Objective Methods of Monitoring Usage of Orthotic Devices for the Extremities: A Systematic Review

Orthoses are commonly prescribed to relieve symptoms for musculoskeletal and neurological conditions; however, patients stop wearing orthoses as recommended for many reasons. When considering the effectiveness of orthoses, there needs to be an objective way to monitor whether participants wear the orthosis as instructed, because if this is not followed, the orthoses will not work as intended. This review aimed to identify, summarise, and compare objective methods used to measure compliance with orthoses applied to the extremities. Databases (Scopus, Web of Science, Embase, CINAHL, and MEDLINE) were searched for eligible studies. Twenty-three studies were accepted in the final review, including five studies that employed upper limb orthoses, two that employed hip orthoses, and fifteen that employed lower limb orthoses. To measure compliance objectively, studies utilised temperature sensors, pressure sensors, accelerometers, a step counter, or a combination of sensors. All sensor types have their own advantages and disadvantages and should be chosen based on study-specific parameters. Sensor-derived monitoring provides quantitative, objective data that are beneficial in both clinical and research settings. The ideal solution to monitoring compliance would consist of both objective and user-reported aspects that, in combination, would provide an all-encompassing picture of the orthotic treatment prescribed.

Defining the Incidence of Residual Acetabular Dysplasia After Successful Reduction With a Harness

BACKGROUND

The purpose of this study was to evaluate the rate of residual acetabular dysplasia (RAD), defined as an acetabular index (AI) of >90th percentile of age and sex-matched controls, in a cohort of infants successfully treated with the Pavlik harness (PH).

METHODS

We retrospectively studied typically developing infants at a single center, with at least 1 dislocated hip, that was successfully treated with a PH and had a minimum of 48 months follow-up. Hip dislocation was defined as <30% femoral head coverage at rest on pretreatment ultrasound or IHDI grade 3 or 4 on the pretreatment radiograph.

RESULTS

Forty-six dislocated hips (41 infants) were studied (4 males and 37 females). Brace treatment was initiated at an average age of 1.8 months (range: 2 d to 9.3 mo) and was maintained for an average of 10.2 months (range: 2.3 to 24.9 mo). All hips achieved IHDI grade 1 reduction. Five of 46 hips (11%) had an AI >90th percentile at the conclusion of bracing. Average follow-up was 6.5 years (range: 4.0 to 15.2 y). We found a 30% incidence of RAD (14/46 hips) on final follow-up radiographs. Of these hips, 13/14 (93%) had AI <90th percentile at the end of brace treatment. Comparing children with and without RAD, there were no differences in age at the initial visit or brace initiation, total follow-up, femoral head coverage at the initial visit, alpha angle at the initial visit, or total time in the brace (P > 0.09).

CONCLUSION

In a single-center cohort of infants with dislocated hips treated successfully with a PH, we observed a 30% incidence of RAD at a minimum 4.0-year follow-up. Normal acetabular morphology at the end of brace treatment did not result in normal acetabular morphology at the final follow-up in 13/41 hips (32%). We recommend that surgeons should pay close attention to the year-over-year change in both the AI and AI percentile.

LEVEL OF EVIDENCE

Level IV: case series.

Developmental Dysplasia of the Hip: Controversies in Management

PURPOSE OF REVIEW

Many aspects of developmental hip dysplasia (DDH) care and evaluation are still active areas of debate. Recent studies have provided more insight into these topics such as strategies for reducing osteonecrosis, assessing hip reduction after closed and open reduction, and the management of residual acetabular dysplasia.

RECENT FINDINGS

The presence of the ossific nucleus at the time of reduction does not alter the risk of osteonecrosis. The risk of osteonecrosis may be higher when hips are immobilized in excessive abduction. Limited sequence MRI may be the best choice for assessing hip reduction after closed and open reduction; however, new technologies are emerging such as 3D fluoroscopy and perfusion MRI. The treatment of residual acetabular dysplasia with bracing has been shown to be effective and the decision to perform a pelvic osteotomy is based on patient-specific factors. The spectrum of DDH treatment has evolved over the past several decades. Recent studies have provided insights into strategies for osteonecrosis prevention, hip evaluation during after reduction, and the management of residual acetabular dysplasia. However, there is ample room for additional and more rigorous studies guiding advanced imaging for assessing hip reduction such as 3D fluoroscopy and perfusion MRI, as well as the management of residual acetabular dysplasia.

The Clinical Significance of Infolded Limbus on Postreduction Arthrogram in Developmental Dysplasia of the Hip

BACKGROUND

The purpose of this study was to investigate whether presence of an infolded limbus on hip arthrogram at index closed reduction was associated with increased residual dysplasia or secondary surgery.

METHODS

We retrospectively reviewed all patients who underwent closed reduction for dysplasia of the hip with a minimum 2-year follow-up between 1980 and 2016. Demographic data was obtained including the age at reduction and severity of dislocation based on the International Hip Dysplasia Institute (IHDI) classification. Arthrograms performed at time of closed reduction were separately reviewed by 3 fellowship-trained pediatric orthopaedic surgeons to evaluate for an infolded limbus. The primary radiographic outcome was acetabular indices at 2 and 4 years postreduction. We also assessed the presence of avascular necrosis and rate of secondary reconstructive surgery for residual dysplasia.

RESULTS

A total of 182 hips in 165 patients underwent closed reduction at a mean age of 9.8±4.5 mo and were followed a mean of 9.0±4.9 y. An infolded limbus was identified in 20.3% (37/182) hips with substantial agreement among the 3 graders (Fleiss κ=0.75). The frequency of labral infolding increased with the severity of dislocation (8.8%% of IHDI II, 26.7% IHDI III, and 25.0% of IHDI IV hips; P=0.03). Hips with infolded limbus were older at reduction (12.4±5.3 vs. 9.2±5.8 mo, P=0.001). The mean acetabular index was higher in hips with infolded limbus than hips without at 2 years postreduction (34.8±4.8 vs. 32.6±5.8 degrees, respectively; P=0.04). However, multivariate analysis revealed that only the severity of dislocation predicted dysplasia at 2 years postreduction. No significant difference in acetabular index was seen at 4 years postreduction (27.2±7.4 vs. 25.4±6.5 degrees, P=0.24). There was no difference in avascular necrosis between groups (P=0.74). There was no difference in rate of secondary surgery between hips with labral infolding and those without (35% vs. 30%, respectively; P=0.52).

CONCLUSIONS

An infolded limbus was more common in older patients with more severe dislocations. However, it is not associated with increased residual dysplasia or secondary surgery and may have limited utility in decision-making during closed reduction.

LEVEL OF EVIDENCE

Level II-prognostic study.

Residual Acetabular Dysplasia in the Reduced Hip

BACKGROUND

Residual acetabular dysplasia occurs in up to a third of patients treated successfully for developmental dysplasia of the hip (DDH) and has been found to be a significant risk factor for early hip osteoarthritis (OA).

DISCUSSION

Age at the time of initial reduction and the initial severity of DDH have been linked to residual acetabular dysplasia. An anteroposterior pelvic radiograph is the main diagnostic modality, but MRI also provides valuable information, particularly in equivocal cases. The literature supports intervening when significant residual acetabular dysplasia persists at 4-5 years of age, and common surgical indications include acetabular index (AI) > 25°-30°, lateral center-edge angle (LCEA) < 8°-10°, and a broken Shenton's line on radiographs; and a cartilaginous acetabular angle (CAI) > 18°, cartilaginous center-edge angle (CCE) < 13°, and/or the presence of high-signal intensity areas on MRI. Surgical options include redirectional pelvic osteotomies and reshaping acetabuloplasties, which provide comparable radiographic and clinical results.

CONCLUSION

RAD is common after treatment of DDH and requires regular follow-up for diagnosis and appropriate management to decrease the long-term risk of OA. Long-term outcomes of patients treated with pelvic osteotomies are generally favorable, and the risk of OA can be decreased, although the risk of total hip replacement in the long-term remains.

Principles of Bracing in the Early Management of Developmental Dysplasia of the Hip

Bracing is considered a gold standard in treating Developmental Dysplasia of the Hip (DDH) in infants under 6 months of age with reducible hips. A variety of braces are available that work on similar principles of limiting hip adduction and extension. This paper summarises the current evidence regarding bracing in DDH. Most of the literature pertains to the Pavlik harness (PH) and there are few studies for other brace types. Bracing eliminates dislocating forces from the hamstrings, the block to reduction of the psoas and improves the muscle line of pull to stabilise the hip joint. Recent studies have shown no benefit in bracing for stable dysplasia. The rates of PH treatment failure in Ortolani-positive hips have been reported to be high. Barlow positive hips have lower Graf grades and are more amenable to PH treatment. There is consensus that the earlier the diagnosis of DDH and initiation of PH treatment, the better the outcome. Failure rates due to unsuccessful reduction and AVN are higher with treatment initiated after age 4-6 months. Studies have shown no benefits of staged weaning of braces. While there is no maximum time in brace, current consensus suggests a minimum of 6 weeks. The key to successful bracing lies in education and communication with the family.