DDH – Rx Complications

DDH-Rx complications
Developmental Dysplasia of the Hip – Tx Complications

Redislocation
– have to be ready for this; this is just a known, recognized complication, not a failure of treatment
– if redislocates after a closed reduction – immediately perform another closed reduction, arthrography, spica etc.
– if redislocates after an open reduction – this is a bit trickier; if the skin is okay, you can try the open reduction again. Be prepared for the fact that achieving a stable reduction and repeating the capsulorrhaphy may be difficult the second time around.

Avascular Necrosis
– does not happen in the untreated DDH
– highly correlated with forceful reductions of the hip and wide abduction (kinks off the posterior vessels)
– also associated with damage to the medial femoral circumflex during medial open reduction
– there are a number of classification systems; Kalamchi/MacEwen – basically, you want to know:
– does the avascularity involve just the ossific nucleus? These do well.
– does it involve the lateral aspect of the physis? The femoral head tilts into valgus gradually as medial side grows
– does it involve the central part of the physis? Get coxa breva (short neck) but with no change in neck shaft angle.
– is the whole fuckin’ head/physis complex toast? These develop marked shortening of the neck with varus deformity
and trochanteric overgrowth.

– If the physis is dead, abit of length is lost (most of the femoral growth is at the distal physis) but more importantly have a short neck and trochanteric overgrowth, causing an adductor limp because of the mechanical disadvantage of having an elevated trochanter and short abductors.
– Treatment: either arrest the growth of the greater trochanter before the age 8 (or sometime before the trochanter reaches the level of the femora head), or if already past, transfer the greater trochanter distally