Abstract
Reorientation of the dysplastic acetabulum can be achieved with a simple Salter or Dega osteotomy. While this may be beneficial in children, it is usually insufficient in more severe adolescent or adult dysplasias. Improvement in coverage with double and triple oste-otomies is limited by the size of the acetabular fragment and the ligaments connected to the sacrum. Correction is achieved with the notable asymmetry of the pelvis. The development of these osteotomies results in making the acetabular fragment smaller and smaller and without ligamentous connection between sacrum and sciatic bone. The periacetabular Ganz osteotomy (PAO) is a compromise of the size of acetabular fragment between triple and dial (spherical) osteotomies. The acetabular fragment as in triple Carlioz and Tonnis osteotomies has no connection with the sacrum, what results in enormous possibilities for correction . Finally, the pelvic ring is left untouched.
The aim of the study is to present our experience and early results in using this technique in the treatment of dysplasia with subluxation in adolescent and young adults.
Our material consists of 42 hips in 35 patients (29 females and 6 males) operated in years 1998 – 2001. In 7 cases there was bilateral involvement, the rest were unilateral. The age at operation was between 11 and 39 years, mean 17,5 years. The indication for the PAO in all cases was acetabular dysplasia with different degree of subluxation. In 10 hips there was severe subluxation with CE below 0°, in 4 hips the signs of osteoarthritis were found. The follow-up ranged from 1 to 4 years. Methods. The PAO as a single procedure was done in 39 hips. In only 3 hips the subtrochanteric DVO was done simultaneously. In clinical pre-op. and post-op. examination the following factors were regarded: pain, limping, Trendelenburg sign, range of motion, leg length discrepancy. Radiographic pre-op. and post-op. examination consisted of AP view of the pelvis, false profile and AP view with leg in abduction. Classic and anterior CE angles were measured.
Results. Flexion slightly decreased from pre-op. 90-140° (av.118°) to 80-130° (av.104°) post-op., abduction left unchanged 15-80° (av.40°) and 15-80° (40°) respectively, adduction slightly increased 15-50° (av.31°) and 20-50° (av. 33°). The range of rotation did not change after operation. The sign of Trendelenburg was found in 27 hips pre-op. and in 8 hips post-op. Pain was found in 29 hips before operation and in 4 after surgery. Either classic or anterior CE angle increased after surgery to the normal value in almost all cases from −14° to 34° and from −10° to 35° respectively. We had a rather low complication rate. In our group 35 operations were done without any complications. In 7 hips the following complications were found: in 1 hip overcorrection and in 2 others insufficient correction, 2 urinary infections, ectopic bone formation in 1 hip, local soft tissue infection in 1 hip and in 1 bad scar formation. We did not find any signs of AVN in our series.
Local Host: British Society for Children’s Orthopaedic Surgery. Conference Theme: Congenital Deficiencies of the Lower Limb. These abstracts were prepared by A.Catterall.
