Background
The articular and soft tissue deficiencies associated with congenital femoral deficiency are reported to predispose to joint dislocation during limb lengthening, which would negate the value of limb lengthening.
Patients and methods
The cases of 17 children who suffered hip and/or knee dislocation as a result of femoral lengthening for congenital femoral deficiency of Paley’s classification type 1 and 2a were included. Their ages ranged from 4.5 to 13 years (average: 6.8 years). The average lengthening achieved at the time of diagnosis of the dislocation was 5.7±1.048 cm (range: 4.5–8 cm). Hip dislocation only was present in seven (41%) cases, knee dislocation only in six (35%) cases, and combined dislocation in four (24%) cases.
Results
A center-edge angle of Wiberg less than 22° had a highly significant effect on hip dislocation (=0.001), and all knee dislocations were associated with a hypoplastic lateral femoral condyle. Both joint dislocations were common when the child had a center-edge angle of 15–20° together with a hypoplastic lateral femoral condyle.
Discussion
and conclusion Hip dislocations were managed with soft tissue release and pericapsular acetabuloplasty with satisfactory Mckay’s hip scores in all cases. Knee dislocations were reduced and stabilized by means of extra-articular ligament reconstruction with satisfactory Judet’s knee criteria in 82% of cases.