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

Abstract

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.

Children’s orthopaedics

“…Therefore, this group from Dallas (Texas, USA) investigated whether increased residual dysplasia or secondary surgery were associated with this finding. 6 All patients undergoing a closed reduction with a minimum two years of follow-up, over an impressive 36-year period at their institution, were studied. The authors collated demographic data, and the severity of dislocation was assessed based on the International Hip Dysplasia Institute (IHDI) classification.…”

What’s New in Pediatric Orthopaedics

“…However, Dornacher et al found that, in hips with residual acetabular dysplasia after Pavlik harness treatment, a majority reach normative values by preschool age, with 35 of 36 hips improving from a severe Tönnis classification by the third follow-up 27 . In the treatment of hip dislocation with closed reduction, a retrospective review of 182 hips found that 20% had an infolded labrum, but noted that this was not associated with an increased rate of residual acetabular dysplasia or need for a secondary surgical procedure 28 .…”