[Squatting cast for biomechanical treatment of decentred hip joints]. / Sitz-Hock-Gips zur biomechanischen Behandlung dezentrierter Hüftgelenke.

The so-called "congenital" luxation of the hip joint is endemic in Central Europe and occurs in about 1% of all newborn infants. By the means of ultrasonographic diagnosis according to the Graf method an early detection instantly after birth has become a good clinical routine in the German-speaking countries. Sonography-based conservative treatment has become the gold standard. The cast in squatting ("human") position is a standard procedure in order to retain the originally decentred or unstable hip joints in the reduced position: 100° flexion and 50° abduction are necessary to fix the hip joint in the reduced position without the risk of avascular necrosis. After the fixation in a squatting-cast, a period of functional bracing in flexed position enhances bony maturation. This two-phase functional conservative treatment can avoid later osteotomies or even early total hip replacement.

Anatomically adapted, HA coated SBG stem--ten years of successful implantation.

For stable implantation of anatomically conforming femur prostheses, modifications that accommodate curving and torsion are necessary. In accordance to this concept, the anatomically shaped SBG stem has been developed. The first consecutive implantations were evaluated. 194 primary arthroplasties with uncemented anatomical, HA coated SBG stems were performed. Mean patient age was 61 years. 143 patients with 151 (78%) SBG stems were followed-up clinically and radiologically after an average of 10 (9-11) years. So far, only one implant had to be revised. Survivorship with revision of the femoral component is 99.5% at ten years. The mean postoperative Harris Hip Score was 92. Patients over 75 years had a score of 89; younger patients under 40 years scored 94. Sclerotic lines were seen in zone I or VII in 8%. Minor femoral remodeling (Type 1) occurred proximally in 75%. Minor thickening of the femur at the level of the tip of the prosthesis could be observed in 27% of the cases. There is no correlation between compacta thickening and clinical symptoms (p=0.15). The anatomical shape, the oval diameter and the longitudinal grooves secure stable primary fixation. Together with the HA coating, which enhances osseointegration, the SBG stem has a high success rate in the medium and long term.