The fate of inverted limbus in children with developmental dysplasia of the hip: Clinical observation

Prediction of the Labrum Shape in Patients With Developmental Dysplasia of the Hip Based on Pelvic Radiography

BACKGROUND

The shape of the labrum is strongly correlated with outcomes of developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) is the generally preferred imaging technique for observing the labrum.

PURPOSE

We aimed to find a correlation between the labrum shape and anterior-posterior (AP) pelvic measurements in children with DDH.

METHODS

Preoperative AP pelvic x-ray radiographs and MRI of patients with DDH from January 2019 to December 2021 were retrospectively collected and divided into three groups by labrum shape on MRI: everted, partly inverted, and inverted. The acetabular length ratio (RAL) in patients with unilateral DDH and the ratio of acetabular length to interpedicular distance (RALI) in all patients were calculated. T-tests were used to analyze differences between the groups. Receiver operating characteristic curve (ROC) analysis was performed between the everted group and the partly inverted and inverted groups.

RESULTS

We found significant differences in RAL between the everted and partly inverted groups, everted and inverted groups, and everted and combined groups. The ROC analysis showed that the best cutoff value for RAL was 0.945 between the everted and combined groups, with an area under the curve (AUC) of 88.4%. The sensitivity at the best RAL value was 0.783, and the specificity was 0.887. Moreover, we observed a significant difference in RALI between the everted, partly inverted, and inverted groups, as well as between the everted and combined groups. The optimal cutoff value for RALI between the everted and combined groups was 0.575, with an AUC of 74.5%. The sensitivity at the best RALI value was 0.765, and the specificity was 0.674.

CONCLUSION

The RAL or RALI values on pelvic AP radiographs can be used to predict the shape of the labrum.

LEVEL OF EVIDENCE

III.

Hip Morphology on Post-Reduction MRI Predicts Residual Dysplasia 10 Years After Open or Closed Reduction

BACKGROUND

There is limited evidence supporting the value of morphological parameters on post-reduction magnetic resonance imaging (MRI) to predict long-term residual acetabular dysplasia (RAD) after closed or open reduction for the treatment of developmental dysplasia of the hip (DDH).

METHODS

We performed a retrospective study of 42 patients (47 hips) undergoing open or closed reduction with a minimum 10 years of follow-up; 39 (83%) of the hips were in female patients, and the median age at reduction was 6.3 months (interquartile range [IQR], 3.3 to 8.9 months). RAD was defined as additional surgery with an acetabular index >2 standard deviations above the age- and sex-specific population-based mean value or Severin classification grade of >2 at last follow-up. Acetabular version and depth-width ratio, coronal and axial femoroacetabular distance, cartilaginous and osseous acetabular indices, transverse ligament thickness, and the thickness of the medial and lateral (limbus) acetabular cartilage were measured on post-reduction MRI.

RESULTS

At the time of final follow-up, 24 (51%) of the hips had no RAD; 23 (49%) reached a failure end point at a median of 11.4 years (IQR, 7.6 to 15.4 years). Most post-reduction MRI measurements, with the exception of the cartilaginous acetabular index, revealed a significant distinction between the group with RAD and the group with no RAD when mean values were compared. The coronal femoroacetabular distance (area under the receiver operating characteristic curve [AUC], 0.95; 95% confidence interval [CI], 0.90 to 1.00), with a 5-mm cutoff, and limbus thickness (AUC, 0.91; 95% CI, 0.83 to 0.99), with a 4-mm cutoff, had the highest discriminatory ability. A 5-mm cutoff for the coronal femoroacetabular distance produced 96% sensitivity (95% CI, 78% to 100%), 83% specificity (95% CI, 63% to 95%), 85% positive predictive value (95% CI, 65% to 96%), and 95% negative predictive value (95% CI, 76% to 100%). A 4-mm cutoff for limbus thickness had 96% sensitivity (95% CI, 78% to 100%), 63% specificity (95% CI, 41% to 81%), 71% positive predictive value (95% CI, 52% to 86%), and 94% negative predictive value (95% CI, 70% to 100%).

CONCLUSIONS

Coronal femoroacetabular distance, a quantitative metric assessing a reduction's concentricity, and limbus thickness, a quantitative metric assessing the acetabulum's cartilaginous component, help to predict hips that will have RAD in the long term after closed or open reduction.

LEVEL OF EVIDENCE

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

Hip arthrogram parameters predict radiographic outcomes of patients with developmental dysplasia of the hip treated by closed reduction

Objective

This study aimed to investigate the relationship between intraoperative hip arthrogram parameters and residual acetabular dysplasia (RAD) and avascular necrosis of the femoral head (AVN) in children with developmental dysplasia of the hip (DDH) treated by closed reduction.

Methods

We retrospectively analyzed the data of 102 patients (110 hips; mean age, 14.6 months ± 4.7 months) with DDH treated by closed reduction. A hip arthrogram was routinely performed during the operation. The femoral head coverage rate (FHC), medial pool distance of the hip (MPD), labral inversion, and reduction quality classification were evaluated under the hip arthrogram. The presence of RAD and AVN was assessed on radiographs at the last follow-up. The relationship between each arthrogram parameter and RAD as well as AVN was investigated using a t-test, chi-square test, and logistic regression.

Results

The overall FHC and medial pool distance of the hip (MDP) averaged 42.2% ± 12% and 8.1% ± 11.7%, respectively. There were 80 hips (72.7%) with labral inversion and 30 hips (27.2%) without. The reduction quality was type A in 57 hips (51.8%), type B in 28 hips (25.4%), and type C in 25 hips (22.7%). A total of 32 hips (29%) were in the RAD group, and 78 hips (71%) were in the recovered group according to whether pelvic osteotomy was performed or not and according to the last Severin grade. The FHC was significantly higher in the recovered group than that in the RAD group (P = 0.014). No significant difference was observed in sex, age at reduction, side, preoperative acetabular index, International Hip Dysplasia Institute classification, follow-up time, quality of reduction, MDP, and proportion of labral inversion between the recovered and RAD groups. Logistic regression analysis showed that only the FHC was a risk factor for RAD. The incidence of AVN above type II was 11.8% in this group of patients, and the incidence of AVN was significantly higher in patients with labral inversion (23.2%) than that in those without (7.5%; P = 0.041). Logistic regression analysis showed that labral inversion was a risk factor for AVN.

Conclusion

The FHC measured under arthrogram can predict the occurrence of RAD after closed reduction of DDH, whereas MDP, reduction quality classification, and labral inversion are of little significance. Labral inversion is a risk factor for AVN.

MRI assessment of femoral head docking following closed reduction of developmental dysplasia of the hip

AIMS

Eccentric reductions may become concentric through femoral head 'docking' (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI.

METHODS

We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.

RESULTS

At the end of the first cast period, 73 hips (79.3%) had a FTD < 1 mm. Multiple regression analysis showed that FTD (p = 0.011) and immobilization duration (p = 0.028) were associated with complete reduction. At the end of the second cast period, all 92 hips achieved complete reduction. The LACC on initial MRI was inverted in 69 hips (75.0%), partly inverted in 16 hips (17.4%), and everted in seven hips (7.6%). The LACC became everted-congruent in 45 hips (48.9%) and 92 hips (100%) at the end of the first and second cast period, respectively. However, a residual inverted labrum was present in 50/85 hips (58.8%) with an initial inverted or partly inverted LACC.

CONCLUSION

An eccentric reduction can become concentric after complete reduction and LACC remodelling following CR for DDH. Varying immobilization durations were required for achieving complete reduction. A residual inverted labrum was present in more than half of all hips after LACC remodelling.Cite this article: Bone Joint J 2023;105-B(2):140-147.

MRI Predictors of Residual Dysplasia in Developmental Dysplasia of the Hip Following Open and Closed Reduction

BACKGROUND

Following open or closed reduction for children with developmental dysplasia of the hip, there remains a significant risk of residual acetabular dysplasia which can compromise the long-term health of the hip joint. The purpose of this study was to use postoperative in-spica magnetic resonance imaging (MRI) data to determine factors predictive of residual acetabular dysplasia at short-term follow-up.

METHODS

We retrospectively reviewed 63 hips in 48 patients which underwent closed or open reduction and spica casting for developmental dysplasia of the hip. MRI performed in-spica at ∼3-week follow-up were used to assess 11 validated metrics and 2 subjective factors. Acetabular index (AI) was measured on anteroposterior pelvic radiographs at 2-year postoperative follow-up. Binary logistic regression was then used to identify variables predictive of residual dysplasia, defined as an AI greater than the 90th percentile for age based on historic normative data.

RESULTS

Average age at surgical reduction was 9.3±3.2 months. 58.7% (37/63) of reductions were open. A total of 43 (68.3%) hips demonstrated residual acetabular dysplasia at 2 years postoperatively based on normative values. In those with persistent dysplasia, patients were on average older at the time of reduction (10.0 mo±3.2 vs. 8.0 mo±2.8, P=0.010) and more likely female (88.4% vs. 60.0%, P=0.010). Patients with residual dysplasia were more likely to have mild subluxation on postoperative MRI (40.0% vs. 10.5%, P=0.022). Hips with a cartilaginous acetabular index (CAI) of >23 degrees were 7.6 times more likely to develop residual dysplasia. Type of reduction (ie, closed vs. open) did not appear to influence the rate of residual dysplasia (P=0.682).

CONCLUSION

In this series, the rate of residual dysplasia after surgical reduction was higher than most previous reports, with no appreciable difference between closed and open reductions. Older age, female sex, and a higher CAI were associated with a greater risk of persistent radiographic dysplasia. In particular, hips with a CAI >23 degrees were 7.6 times more likely to be dysplastic at 2-year follow-up.

LEVEL OF EVIDENCE

Level III.

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 congenital hip dysplasia

Residual hip dysplasia may exist despite appropriate treatment of congenital hip dysplasia (CHD). The abnormalities chiefly affect the acetabulum and can lead to premature osteoarthritis. Although the main cause is delayed treatment of CHD, primary lesions are also possible and may be worsened by the initial treatment itself. Residual hip dysplasia must be detected during the follow-up of patients with CHD. The antero-posterior radiograph of the pelvis is the main diagnostic tool. However, the importance of non-ossified anatomical structures requires additional investigations such as arthrography and magnetic resonance imaging. The risk of premature osteoarthritis is difficult to predict based only on the imaging-study findings. Hip dysplasia is best treated before 5 years of age. The work-up at this age should allow determination of the best treatment. Surgery is required but should not be performed unnecessarily. The decision rests on the absence of improvement in the radiographic criteria and on the findings from additional imaging studies. The usual treatment is Salter's osteotomy, during which excessive anterior displacement should be avoided. At adolescence, the information provided by radiography in the coronal plane should be completed by a three-dimensional evaluation of the acetabulum and an assessment of the quality of the labrum. The shelf procedure has been proven to relieve pain and to significantly postpone the need for hip arthroplasty, when performed early, before the development of visible osteoarthritis, and on a congruent hip. Chiari's osteotomy has a role to play in complex dysplasia affecting both the acetabulum and the femur. Periacetabular osteotomy is getting more used thanks to cooperation between paediatric and adult orthopaedic surgeons. This osteotomy provides optimal correction in all three dimensions.

Management and effects of residual limbus inversion following closed reduction in developmental hip dysplasia: Protocol for a multicenter randomized controlled trial

Closed reduction is a common treatment method for developmental dysplasia of the hip (DDH) in children aged 6-18 months. Residual acetabular dysplasia (RAD) is the most common complication associated with closed reduction. Residual limbus inversion (RLI) is a common condition following DDH closed reduction. Previously, we confirmed that when limbus inversion exceeds 32.2% of the acetabular depth after closed reduction, RLI persists and leads to RAD; however, this was based on a small cohort with a short-term follow-up period. The long-term fate of RLI and the correlation between RLI and RAD have yet to be verified. Therefore, this multicenter clinical study protocol was designed in three parts to investigate the effect of RLI on acetabular development after closed reduction of DDH (a multicenter retrospective cohort study), effect of RLI clearance on acetabular development (a multicenter retrospective and prospective randomized controlled study), and influence of inverted limbus clearance on acetabular development during DDH reduction (a multicenter prospective cohort study). Statistical analysis was performed by assessing the basic measures of acetabular development including the acetabular index and central-edge angle using frontal pelvic radiographs; the magnitude of limbus inversion, cartilaginous acetabular index, and T1ρ mapping values were measured using magnetic resonance imaging. The multicenter retrospective cohort studies required 5 years of follow-up period at minimum, and the prospective randomized controlled studies required reviews of frontal pelvic radiographs every 6 months as well as data pooling every 2 years to compare the short- and mid-term outcomes of hip joint morphological development between the two groups of pediatric patients. This research program is expected to verify that RLI following closed reduction of DDH can affect acetabular development and that limbus excision during DDH reduction can improve postoperative RAD. Therefore, the indication and timing of surgical intervention for RLI after closed reduction of DDH provide a basis for revising the acceptable criteria for utilizing closed reduction of DDH to reduce the incidence of osteoarthritis caused by RAD following DDH treatment. Clinical Trial: http://www.chictr.org.cn/showproj.aspx?proj=35045 (ChiCTR1900020996).

Electromyographic Biofeedback for Stress Urinary Incontinence or Pelvic Floor Dysfunction in Women: A Systematic Review and Meta-Analysis

Electromyographic biofeedback (EMG-BF) can be regarded as an adjuvant to pelvic floor muscle (PFM) training (PFMT) for the management of stress urinary incontinence (SUI). This meta-analysis aimed to compare the efficacy of PFMT with and without EMG-BF on the cure and improvement rate, PFM strength, urinary incontinence score, and quality of sexual life for the treatment of SUI or pelvic floor dysfunction (PFD). PubMed, EMBASE, the Cochrane Library, Web of Science, Wanfang, and CNKI were systematically searched for studies published up to January 2021. The outcomes were the cure and improvement rate, symptom-related score, pelvic floor muscle strength change, and sexual life quality. Twenty-one studies (comprising 1967 patients with EMG-BF + PFMT and 1898 with PFMT) were included. Compared with PFMT, EMG-BF + PFMT had benefits regarding the cure and improvement rate in SUI (OR 4.82, 95% CI 2.21–10.51, P < 0.001; I² = 85.3%, P_{heterogeneity} < 0.001) and in PFD (OR 2.81, 95% CI 2.04–3.86, P < 0.001; I² = 13.1%, P_{heterogeneity} = 0.331), and in quality of life using the I-QOL tool (SMD 1.47, 95% CI 0.69–2.26, P < 0.001; I² = 90.1%, P_{heterogeneity} < 0.001), quality of sexual life using the FSFI tool (SMD 2.86, 95% CI 0.47–5.25, P = 0.019; I² = 98.7%, P_{heterogeneity} < 0.001), urinary incontinence using the ICI-Q-SF tool (SMD − 0.62, 95% CI − 1.16, − 0.08, P = 0.024), PFM strength (SMD 1.72, 95% CI 1.08–2.35, P < 0.001; I² = 91.4%, P_{heterogeneity} < 0.001), and urodynamics using Qmax (SMD 0.84, 95% CI 0.57–1.10, P < 0.001; I² = 0%, P_{heterogeneity} = 0.420) and MUCP (SMD 1.54, 95% CI 0.66–2.43, P = 0.001; I² = 81.8%, P_{heterogeneity} = 0.019). There was limited evidence of publication bias. PFMT combined with EMG-BF achieves better outcomes than PFMT alone in SUI or PFD management.