Acetabuloplasties at Open Reduction Prevent Acetabular Dysplasia in Intentionally Delayed Developmental Dysplasia of the Hip: A Case-control Study.
BACKGROUND
Avascular necrosis (AVN) and residual acetabular dysplasia are the two main complications of developmental dysplasia of the hip (DDH) treatment. Although early reduction of the hip may decrease the incidence of residual dysplasia, it may increase the incidence of AVN and vice versa. However, we do not know if changes in surgical technique may lead to a modification in these outcomes.


OBJECTIVE
Does an incomplete periacetabular acetabuloplasty, as an added step to delayed open reduction, (1) diminish the risk of developing acetabular dysplasia; or (2) increase the rate of AVN compared with patients treated with open reduction alone?


METHODS
We conducted a retrospective matched case-control study comparing 22 patients (27 hips) with early isolated DDH who underwent intentionally delayed open reduction and acetabuloplasty from 2004 to 2010 and followed up > 4 years (88% of the cohort) with early historic controls treated with delayed open reduction alone. Of 53 patients available for matching, 45 (85%) had enough followup (> 10 years) to be considered. They were matched one to one for age at presentation and bilaterality (fuzz 45, 0). This generated a control group of 25 patients (27 hips). The mean followup was different between the groups (p < 0.001). Residual dysplasia considered when center-edge angle < 15° (6-13 years old) or < 20° (≥ 14 years old) or as a nonevolving acetabular index > 30° and pelvic osteotomies were used as our primary outcomes. The proportion of patients with AVN was also compared.


RESULTS
Patients treated with open reduction and an incomplete periacetabular acetabuloplasty were less likely to develop acetabular dysplasia and undergo pelvic osteotomies than were patients in the control group (0% [zero of 27] versus 37% [10 of 27]; odds ratio [OR], 11; 95% confidence interval [CI], 2-80; p = 0.02 and 0% [zero of 27] versus 26% [seven of 27]; OR, 8; 95% CI, 1-60; p = 0.025, respectively). With the available numbers, there was no difference in terms of the proportion of patients who developed AVN (11 of 27 [41%] both groups; OR, 1; 95% CI, 1-2; p = 1).


CONCLUSIONS
The addition of an incomplete periacetabular acetabuloplasty to all hips undergoing open reduction eliminated residual acetabular dysplasia, whereas it did not appear to have deleterious effects as evidenced by the similar AVN proportion.


METHODS
Level III, therapeutic study.
University Hospitals North Midlands, Stoke-on-Trent, UK.
M Belen
MB
Carsi
University of Southampton and University Hospital Southampton Foundation Trust, University Hospital Southampton, Tremona Road, Southampton, SO16 6YD, UK. ortho@soton.ac.uk.
Nicholas M P
NM
Clarke
D000077:Acetabulum / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D000367:Age Factors; D002648:Child; D002657:Child Development; D002675:Child, Preschool; D005260:Female; D005271:Femur Head Necrosis / Q000209:etiology; D006618:Hip Dislocation, Congenital / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D006621:Hip Joint / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D019637:Orthopedic Procedures / Q000009:adverse effects*; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D011859:Radiography; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome