Can EDS Cause AVN of the Hip?
No, Ehlers-Danlos Syndrome (EDS) does not directly cause avascular necrosis (AVN) of the hip. However, AVN can occur as a serious iatrogenic complication of treatment for hip instability and congenital hip dislocation, which are common musculoskeletal manifestations of EDS.
Understanding the Relationship Between EDS and Hip Pathology
Primary Hip Problems in EDS
EDS causes hip pathology through connective tissue abnormalities, not through AVN:
- Congenital hip dislocation occurs frequently in EDS, particularly in arthrochalasia type (aEDS), where bilateral congenital hip dislocations are a defining feature 1
- Hip instability and recurrent subluxations result from ligamentous laxity and abnormal collagen structure affecting the ligamentum teres, labrum, and joint capsule 2, 3
- Joint hypermobility is a cardinal feature of EDS, with the Beighton scale used for diagnosis requiring scores ≥5/9 in adults under 50 years 4, 5
AVN as a Treatment Complication, Not a Disease Feature
The critical distinction is that AVN develops as a complication of hip treatment in EDS patients, not from the syndrome itself:
- Closed reduction under general anesthesia for congenital hip dislocation carries high AVN risk, with 4 of 5 hips developing AVN after closed reduction in one EDS cohort 6
- Treatment of developmental dysplasia of the hip (DDH) identifies AVN as "the most serious complication of treatment" and "a predictor of poor prognosis" 7
- Multiple surgical procedures are often required in EDS patients with hip dislocation (averaging 42 procedures in one series), increasing cumulative AVN risk 6
Clinical Implications and Management Approach
Why EDS Patients Are at Higher Risk for Treatment-Related AVN
- Difficulty achieving and maintaining reduction due to severe ligamentous laxity requires more aggressive interventions 6
- Tissue fragility complicates surgical technique and healing 3, 8
- Need for both femoral and innominate osteotomies to maintain reduction increases surgical complexity 6
Surgical Considerations to Minimize AVN Risk
When treating hip pathology in EDS patients:
- Avoid closed reduction under general anesthesia when possible, given the 80% AVN rate observed in one series 6
- Plan for open surgical reduction with capsular plication and ligament reconstruction rather than relying on closed techniques 2, 6
- Use meticulous surgical technique to minimize vascular and tissue trauma, particularly critical in vascular EDS (type IV) 7
- Consider ligamentum teres reconstruction with allograft for severe hip instability, which has shown positive outcomes at 1-year follow-up 2
Surveillance and Long-term Outcomes
- Expect multiple procedures: EDS patients with congenital hip dislocation typically require numerous surgical interventions throughout childhood 6
- Monitor for AVN development: Clinical outcomes may appear satisfactory in 75% of hips, but radiographic outcomes are satisfactory in only 37.5% due to AVN and other complications 6
- Functional limitations are common: In arthrochalasia EDS, 33% of patients become wheelchair-bound or unable to walk unaided despite treatment 1
Common Pitfalls to Avoid
- Do not attribute AVN to EDS itself when evaluating hip pain in these patients—investigate treatment history and consider other AVN risk factors (corticosteroids, trauma, alcohol use)
- Do not assume standard DDH treatment protocols apply to EDS patients without modification for their increased tissue fragility and ligamentous laxity 6
- Do not overlook vascular EDS (type IV) when planning any surgical intervention, as these patients have extreme vascular fragility requiring specialized surgical approaches 7, 8
- Do not delay genetic testing to confirm EDS subtype, as this guides surgical planning and risk stratification 4, 5