DDH 24+ Months

Modern Study Review (AI-Generated)

High-Yield Summary

Developmental Dysplasia of the Hip (DDH) diagnosed after 24 months presents unique challenges due to established soft tissue contractures and acetabular dysplasia. Closed reduction is generally contraindicated in this age group because of the high risk of avascular necrosis (AVN) and failure to maintain reduction. Surgical management typically involves open reduction combined with pelvic and femoral osteotomies to restore hip stability and optimize long-term function.

Key Diagnostic Findings

Anatomy

Pathology: Dislocated or subluxated femoral head with a shallow, dysplastic acetabulum.
Soft tissues: Contracted capsule, hypertrophied ligamentum teres, and tight iliopsoas tendon.
Osseous changes: Acetabular dysplasia and femoral head deformity may be present.

Clinical Presentation

Limp or waddling gait.
Limited abduction of the affected hip.
Positive Galeazzi sign (shortened limb on the affected side).
Older children may present with leg length discrepancy and pain.

Imaging

X-rays: AP pelvis showing dislocation, acetabular index, and femoral head position.
CT/MRI: Used preoperatively to assess femoral head viability, acetabular morphology, and soft tissue interposition.
Ultrasound: Limited utility after 6 months of age.

Classification Systems

Classification	Description	Clinical Use
Tönnis Classification	Grades hip dislocation severity (I-IV) based on femoral head displacement	Guides surgical planning
IHDI (International Hip Dysplasia Institute) Classification	Modern alternative to Tönnis, focusing on femoral head position relative to acetabulum	More reproducible in older children

Current Gold Standard Treatment

Non-operative

Generally not indicated after 24 months due to low success rates and high risk of complications.
Bracing or casting may be adjunctive postoperatively but not primary treatment.

Operative Indications

Irreducible hip dislocation or subluxation after 24 months.
Failed previous closed reduction attempts.
Significant acetabular dysplasia requiring correction.

Operative Treatment

Open Reduction: Essential to remove obstacles to reduction (ligamentum teres, pulvinar tissue).
Pelvic Osteotomy:
Salter Osteotomy: Redirects acetabulum to improve coverage; preferred in children 18 months to 6 years with adequate acetabular cartilage.
Alternatives (e.g., Pemberton, Dega) may be considered based on acetabular morphology.
Femoral Osteotomy:
Shortening osteotomy: Reduces tension on the femoral head to prevent AVN.
Varus and derotation osteotomy: Corrects femoral head alignment and anteversion.
Combined procedures optimize hip stability and reduce AVN risk.

Modern Complications & Outcomes

Complications

Complication	Description	Prevention/Management
Avascular Necrosis (AVN)	Loss of femoral head blood supply, leading to collapse	Femoral shortening osteotomy reduces tension; careful surgical technique
Residual Dysplasia	Persistent shallow acetabulum causing instability	Adequate pelvic osteotomy and follow-up imaging
Re-dislocation	Failure to maintain reduction	Proper soft tissue release and stable fixation
Leg Length Discrepancy	Due to femoral shortening or growth disturbance	Monitor growth; consider contralateral procedures if needed

Outcomes

Early intervention before age 6 yields better functional and radiographic results.
After age 8 (unilateral) or 6 (bilateral), prognosis worsens; salvage procedures or arthroplasty may be necessary later.
Goal is pain-free, stable, and functional hip with near-normal gait.

Classic Clinical Notes

DDH >24 months

Approach to DDH – 24 Months and Older

This is where you have to start thinking about osteotomies of the pelvis and acetabulum.
Definitely need open reduction here — abandon thoughts of closed reduction, because the femur is up too high and even by some act of God you got it down into the crappy little acetabulum and managed to keep it there, you’d be putting the head at high risk of AVN.
The basic approach here is:
Salter osteotomy
Open reduction
Femoral shortening varus derotation osteotomy

Note: Give up on a unilateral dislocation after age 8; give up on the bilateral dislocation at age 6.

Last Updated on January 25, 2026 by orthonet