hereditary multiple osteochondroma
Introduction
Introduction to hereditary multiple osteochondroma Hereditary multiple osteochondroma is also known as multiple exostosis, continuous dysplasia, hereditary malformation of cartilage dysplasia, etc. At present, most scholars at home and abroad use the name of hereditary multiple osteochondroma. basic knowledge The proportion of illness: 0.0025% Susceptible people: no special people Mode of infection: non-infectious Complications: fracture
Cause
Hereditary multiple osteochondroma etiology
(1) Causes of the disease
The exact cause is unknown.
(two) pathogenesis
1. The volume of osteochondroma in different parts can be greatly different. The lesions of hereditary multiple osteochondroma often become multiple, symmetrical, and the lesions are of different numbers. The osteochondroma of the long tubular bone is the largest. The average diameter is 4cm. In the osteochondroma of flat bone or irregular bone, the maximum diameter is up to 40cm. The pedicled osteochondroma is tubular or mushroom-shaped. The top surface is smooth and can also be nodular, without pedicle. The osteochondroma of the type is disc-shaped, hemispherical or cauliflower-like, and the longitudinal section of the tumor shows three typical structures:
1 The surface layer is a collagenous connective tissue with sparse blood vessels, which is connected to the surrounding periosteum and separated from the surrounding tissue.
2 The middle layer is gray-blue hyaline cartilage, ie the cartilage cap, similar to normal cartilage, usually a few millimeters thick. The thickness of the cartilage cap is related to the age of the patient. Children and adolescents are in the active growth period, and the cartilage thickness can reach 3cm. Adult cartilage caps are thinner and may even be absent. The thickness of cartilage caps is closely related to the development of tumors: thicker means development, thinner means mature, adult osteochondroma patients, such as cartilage caps over 1cm thick , indicating that the tumor is developing, should consider whether there is malignant occurrence,
3 The base layer is the main body of the tumor, the cancellous bone containing the yellow pulp, and the outer edge is the cortical bone connected to the normal bone.
2. The microscopic examination is mainly to examine the cartilage cap of osteochondroma. The histological performance of the cartilage cap of the osteochondroma patient in the growing period is similar to that of the epiphyseal plate. The following are common cases:
1 In young patients, tumor cells grow actively, and most of the binuclear chondrocytes are seen.
2 When tumor growth stops, chondrocytes stop proliferating and degenerative changes occur.
3 When the cartilage layer grows disorder, there may be calcium debris deposits in the cartilage.
4 When osteochondroma occurs malignant, it often turns into chondrosarcoma, the tissue of which shows significant calcification and ossification of cartilage, and chondrocytes have atypical nuclei.
Prevention
Hereditary multiple osteochondroma prevention
There is no effective preventive measure for this disease. Early detection and early diagnosis are the key to the prevention and treatment of this disease.
Complication
Hereditary multiple osteochondroma complications Complications
The complication of hereditary multiple osteochondroma is more common, including skeletal malformations, fractures, vascular and nerve damage, and saccular cyst formation. These complications are the same as those described for single osteochondroma, but the incidence of malignant transformation is high. About 5%.
Symptom
Hereditary multiple osteochondroma symptoms Common symptoms Chondroital dysplasia and... Bone mass The proximal end of the femur is widened
The disease is more male than female, about 3:1, more common in children until the age of 20, most patients have a positive family history, the author's hospital has a father and two daughters at the same time hospitalized cases, the general clinical performance is mostly The bone mass that is touched causes bone deformity due to shortening and bending of the bone. The mass near the joint often causes joint activity limitation. The lesions of hereditary multiple osteochondroma are often symmetrically distributed, and the number of lesions is different. There are more than 100 patients, the typical site of the disease is the femur, tibia, distal and proximal sides of the humerus and the proximal end of the humerus. Experience has shown that if there are no exostoses on the bone around the knee joint, then the hereditary multiple osteochondroma The diagnosis can not be established, located in the sputum, the incidence of the distal part of the ulna is slightly less, compared with single osteochondroma, hereditary multiple osteochondroma is more likely to occur in the scapula, humerus, ribs.
The disease is characterized by defects in bone formation and skeletal deformities, especially in the hip, which can be bilateral hip valgus and widened at the proximal end of the femur. The wrist has a gradual ulnar deviation and the ulna is relatively short. Wait.
Examine
Examination of hereditary multiple osteochondroma
No relevant laboratory tests.
Ordinary X-ray examination: The X-ray feature of the long bone on the osteochondroma is that there is a bony prominence on the surface of the bone, which is connected with the cognac and consists of the cortical bone and the cancellous bone. It is often symmetrical and multiple, due to the tumor. The bottom of the base has different shapes and can be divided into pedicles (one narrow stem, wide top) and no pedicle (basal wide and flat). Osteochondroma often occurs in the metaphyseal tendon ligament attachment, and its growth tends to tendon. And the direction of the force generated by the ligament is the same, such as the thin capillaries, the boundary is clear, with regular point calcification, which is benign growth, such as the cartilage cap is large and thick, the boundary is not clear, with irregular calcification, then Should pay attention to the possibility of its malignant changes. Osteochondroma is similar to the X-ray findings of the short bones of the hand and foot. It is worth noting that there may be small osteochondromas in the toe and distal nodes, called the inferior epiphysis.
Diagnosis
Diagnosis and diagnosis of hereditary multiple osteochondroma
According to the history, clinical manifestations, multiple, symmetry and X-ray examination, the diagnosis is not difficult.
The humerus osteochondroma has a wide base and a large volume. The cartilage cap is diverse and irregular. It is difficult to judge whether the tumor is benign or malignant by X-ray.
The malignant transformation is characterized by an increase in tumor growth rate, a calcification of the cartilage cap, an increase in density, or a flaky or villi-like calcification, and a soft tissue mass, as well as bone destruction and periosteal hyperplasia.
