(P 306) LONG TERM OUTCOMES OF TYPE BIIIA ROTATIONPLASTY AFTER TOTAL FEMUR EXCISION IN CHILDREN

Objective: Total-femur excision poses a significant reconstruction challenge in children. We present long-term results (median over 10 years follow up) type BIIIa rotationplasty after total-femur excisions in children.
We asked following questions - After type BIIIa rotationplasty (1) What are long-term functional outcomes? (2) Is the hip stable? (3) Is rotationplasty limb significantly shorter than the contralateral femur at skeletal maturity? (4) Is there radiographic remodeling of proximal tibia placed in acetabulum? (5) Are subsequent surgical procedures required?

Methods: We evaluated 18, type BIIIa rotationplasties operated over 20 years (2004- 2022). Mean age at surgery was 7.1 years (3.3 to 11 years). Two (11%) patients underwent perioperative hip disarticulation due to vascular compromise, 5 (28%) died of disease after surgery (Median OS-9months, range 6-29). Eleven remain disease free with a median follow up of 119 months (range 24–244).

Results: Mean MSTS score was 23, with 9 of 11 patients participating in recreational sports (competitive swimming, badminton). ‘Hip’ was stable in 8 of 11 patients. Mean difference of the rotationplasty heel with opposite medial joint -line was 1.2 cm (- 4 to +1 cm). Remodeling of proximal tibia (rounding of the condyles) on radiographs was seen in all patients. Apart from the 2 perioperative hip disarticulations, none of the patients required additional surgery.

Conclusion: At a median follow up of over 10 years, type BIIIa rotationplasty offers reliable, enduring, revision-free function after total femur excisions.