Asphericity of the femoral head-neck junction is common in cam-type
femoroacetabular impingement (FAI) and usually quantified using
the alpha angle on radiographs or MRI. The aim of this study was
to determine the natural alpha angle in a large cohort of patients
by continuous circumferential analysis with CT. CT scans of 1312 femurs of 656 patients were analyzed in this
cross-sectional study. There were 362 men and 294 women. Their mean
age was 61.2 years (18 to 93). All scans had been performed for
reasons other than hip disease. Digital circumferential analysis
allowed continuous determination of the alpha angle around the entire
head-neck junction. All statistical tests were conducted two-sided;
a p-value < 0.05 was considered statistically significant.Aims
Methods
Despite the high regenerative capacity of bone, large bone defects often require treatment involving bone grafts. Conventional autografting and allografting treatments have disadvantages, such as donor site morbidity, immunogenicity and lack of donor material. Bone tissue engineering offers the potential to achieve major advances in the development of alternative bone grafts by exploiting the bone-forming capacity of osteoblastic cells. However, viable cell culture models are essential to investigate osteoblast behavior. Three-dimensional (3D) cell culture systems have become increasingly popular because biological relevance of 3D cultures may exceed that of cell monolayers (2D) grown in standard tissue culture. However, only few direct comparisons between 2D and 3D models have been published. Therefore, we performed a pilot study comparing 2D and 3D culture models of primary human osteoblasts with regard to expression of transcription factors RUNX2 and osterix as well as osteogenic differentiation. Primary human osteoblasts were extracted from femoral neck spongy bone obtained during surgery procedures. Primary human osteoblasts of three donor patients were cultured in monolayers and in three different 3D culture models: 1) scaffold-free cultures, also referred to as histoids, which form autonomously after multilayer release of an osteoblast culture; 2) short-term (10-day) collagen scaffolds seeded with primary human osteoblasts (HOB); 3) long-term (29-day) collagen scaffolds seeded with HOB. Expression levels of transcription factors RUNX2 and osterix, both involved in osteoblast differentiation, were investigated using quantitative PCR and immunohistochemical staining. Furthermore, markers of osteogenic differentiation were evaluated, such as alkaline phosphatase activity, osteocalcin expression, and mineral deposition, as well as the expression of collagen type I and fibronectin extracellular matrix proteins.Introduction
Patients and Methods
Osteochondrosis juvenilis is caused by a dysfunction of endochondral ossification. Several epiphyses and apophyses can be affected, but osteochondrosis juvenilis of the medial malleolus has not been reported. We describe a 12-year-old boy with bilateral pes planovalgus who was affected by this condition. Conservative management was successful. The presentation, aetiology and treatment are described and the importance of including it in the differential diagnosis is discussed.
The project aim was to minimize these two major problems by using computer assisted techniques for exact intraoperative virtual 3D planning including a detailed biomechanical analysis (as change of head offset, torsion, leg length etc.).
So without changing the standard operative procedure the method can be of high clinical importance to improve the accuracy of the planning and the consecutive operative realization for a precise fragment positioning and the plate location without penetrating the isthmus of the femoral neck. So it can potentially help to reduce intraoperative complications and the use of the fluoroscope to minimally 4 frames for the whole procedure.
We have to deal with an increasing number of patients who are suffering from a femoral neck fracture. In Ger-many in 1996 135.000 patients with this kind of fracture were treated. These fractures are usually found in old people and have a high complication rate: Osteonecrosis of the femoral head: 12–43% (Kyle 1994) Pseudarthrosis: 16–28% (Rogmark 2002) The indications for a total hip replacement are: – age >
65years – presence of osteoporosis (also under 65) – daily activity possible (otherwise hemialloarthroplasty) – comorbidity such as osteoarthritis We have to consider several aspects: The mortality rate is lower if we use a hip replacement (THR ~6%, osteosynthesis ~10%) The complication rate is lower if we use hip replacement (THR ~2%, osteosynthesis ~5%) In 30% of cases we have to change from osteosynthesis to a total hip replacement due to secondary complications of osteosynthesis in mobile patients If we look at this data, we must conclude that total hip replacement is the goldstandard in the treatment of femoral neck fractures (with Garden III and IV) in the population older than 65 years. Hemialloarthroplasty is only indicated for patients who are more or less immobilized.