Missing or dysplastic patella

Introduction The tibia is located in front of the knee joint and in front of the lower end of the femur. It is the largest sesamoid in the human body and is embedded in the quadriceps tendon. It is a triangular flat bone. The bottom is upward, the tip is downward, the front is rough, the back is a smooth joint surface, and the knot associated with the femoral condyle participates in the formation of the knee joint. Can be touched on the body surface. The tibia has the function of protecting the knee joint and increasing the knee joint rotation ability. Loss of the humerus or malnutrition is mostly due to the dominant inheritance of the chromosome. The gene locus is linked to the adenylate cyclase and ABO blood group on chromosome 9.

Cause

(1) Causes of the disease

The syndrome is autosomal dominant, and the locus is linked to the adenylate cyclase and ABO blood group on chromosome 9.

(two) pathogenesis

At present, little is known about the pathogenesis of this syndrome. Some people think that it is a collagen disease, and there are abnormalities in the process of collagen synthesis, assembly or degradation. The cytological mechanisms of this disease have not been studied. The lack of non-glomerular basement membrane damage in pathological changes suggests that the various damages in this syndrome may be due to different mechanisms, and not all lesions are associated with basement membrane abnormalities. A small number of patients developed anti-glomerular basement membrane nephritis, supporting the hypothesis that glomerular basement membrane components are abnormal. Using a monoclonal antibody against the Goodpasture epitope, it was found that the glomerular basement membrane of 2/3 patients with renal biopsy specimens did not bind to the monoclonal antibody, suggesting a basement membrane for this syndrome. There is some degree of heterogeneity in the components, which also suggests the presence of Goodpsture antigen deletion or alteration. It is worth noting that it is not clear whether this is a primary or secondary change in this syndrome.

an examination

Related inspection

CT examination of bones and joints of limbs and joints

The main diagnosis of this disease is family history. The typical clinical manifestations are X-ray signs of bone and proteinuria. Renal biopsy is performed as necessary.

Differential diagnosis

The main diagnosis of this disease is family history. The typical clinical manifestations are X-ray signs of bone and proteinuria. Renal biopsy is performed as necessary.

Clinically more common in adolescents, the main manifestations of kidney damage are proteinuria, microscopic hematuria, edema and hypertension, occasionally nephrotic syndrome, the course of the disease is relatively benign, only 10% of patients into the kidney failure. Extrarenal manifestations include nail dystrophies, absent bones on one or both sides, elbow deformities, angular pelvis, and other skeletal abnormalities. Most of the disease is caused by difficulty in walking due to lack of humerus. It can be diagnosed according to typical bone changes, and kidney damage can be diagnosed. Radiological examination showed that the humeral angle was a characteristic change and had a clear diagnostic significance.

It has been reported that a small number of patients have ultrastructural changes in the glomerular basement membrane without bones, skin, nails, and other typical manifestations of this syndrome. These patients are considered to be the frustration or single nephrotic variant of the syndrome. . However, the electron micrographs published by these institutes do not strongly support this view.

Judging the renal biopsy specimens can not only use the glomerular basement membrane moth, and the fibrils must be identified by phosphotungstic acid staining. Because of its higher sensitivity, it is more valuable for diagnosis.

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