DDH – Adult

DDH/Adult
Approach to DDH in Adults

History:
– usu young female with hip pain
– childhood hip problems; risks for DDH; PSHx
– risk factors for AVN- EtOH, steroids, diving
– other joint involvement – generalized inflammatory process
– SHx – occupation, degree of disability

Physical Exam:
– gait & alignment
– trendelenberg sign; pelvic obliquity; LLD; previous incisions
– ROM both hips, knees, ankles, lumbar spine
– NV exam

Xrays:
– location of dislocation – high, intermediate, low
– presence of arthritis
– femoral deformity – short, straight, small, anteverted, coxa valga

Classification: (Athens)
– divide pelvis into thirds
– high – articulates with iliac crest; very poor bone stock
– intermediate
– low
Treatment:
– 1st decide if patient is a candidate for a redirectional osteotomy (acetabulum/femur) à presence of arthritis
– if not a candidate, then conservative treatment 1st à meds, physio, walking aids, modify activity
– if candidate for THA, remember to council about risks of infection, blood loss, nerve injury, LLD, repeat surgery because of young age
** as a rule, should refer to recon surgeon **

Approach:
– need wide exposure of acetabulum
– can use trochanteric osteotomy or vastus slide
– with vastus slide à anterior approach to hip but versatile
– be sure to identify sciatic nerve.

Pitfalls of THA in DDH:
1. femur – short, straight, small, coxa valga, excessive anteversion & ? deformity
2. acetabulum
– location – high, intermediate, low (always bring down a high dislocation)
– bone stock – usu require structural graft (own head or allograft) at superior margin
3. soft tissue
– iliopsoas – usu needs to be released
– abductors – usu need to be retensioned & can be done with trochanteric osteotomy or vastus slide
– sciatic nerve – usu short & determines how much the leg can be safely lengthened (usu 2-3 cm)