Chiari pelvic osteotomy

1. Chiari Pelvic Osteotomy
Khalid Bakarman, MD
KKUH
20th sept 2014

2. Chiari osteotomy
• It was described in 1955 .
• It is a stable ( shelf ) procedure
• It produces a bony platform above the femoral
head ,with capsular fibro cartilage metaplasia
interpostion,by displacing the distal pelvic
fragment after osteotomy of the pelvic
isthmus

3. indication
• Incongruous hip & femoral head coverage
cannot be achieved by other methods of
reconstruction.
• Femoral head is irregular or cannot be
centered in the acetabulum by Abduction/IR.
• Painful subluxated hip
• CEA is less than -10 degress
• Age >8 years

4. Contraindication
• Late OA hip joint
• Sufficient proximal migration of femoral head
,which would preclude an appropriate level of
osteotomy.
• Inability to cover 80%of the femoral head

5. Preoperative planning
• An oblique osteotomy in a proximal &medial
direction start at the lateral margin of the
dysplastic acetabulum .
• Avoid starting either too proximal or too distal
osteotomy level.
• Avoid posterior displacement of the distal
osteotomy fragment by curve other than
horizontal osteotomy cut.
• Avoid medial displacement > 50% of iliac bone b.c
that will reduces the contact area of osteotomy

6. Operative Technique
• An image –translucent operated table,free leg.
• Fluoroscopic imaging
• Smith –Peterson approach.
• 2.5 mm S P at sup –lateral acetabular
edage.and direct 10degree to the transverse
plane of the pelvis.
• After osteotomy push the distal fragment
medially manually or by abduction ,50%
displacement is adequate ,to obtain 80% FHC.

7. • Large cannulated screw or large threaded SP.
• Skin traction of few days ,TWB for 6 weeks
• PT after 6 weeks

11. Complications
• Sciatic nerve injury .
• Superior Gluteal nerve and artery .
• High level osteotomy .
• Low level osteotomy .