congenital tibial pseudarthrosis
Introduction
Introduction to congenital sacral pseudoarthrosis Congenital sacral pseudoarthrosis is a general term for congenital tibia formation or failure. There are many specific types. Each type has its own pathology, disease course and prognosis. It is more common in the lower third of the humerus junction and eventually forms a local part. False joints. The incidence rate of males is slightly higher than that of females, mostly unilateral, and the ipsilateral tibia can also be involved. A small number of patients have a genetic history. basic knowledge The proportion of illness: 0.001% Susceptible people: children Mode of infection: non-infectious Complications: fractures nausea and vomiting
Cause
Congenital sacral pseudoarthrosis
(1) Causes of the disease
The causes of congenital sacral pseudoarthrosis are not fully understood, but there are many theories, such as intrauterine injury theory, vascular malformation and metabolic disorders, but they have been abandoned. Currently, there are three kinds of reasonable ones:
Neurofibromatosis factor (30%):
Congenital sacral pseudoarthrosis is caused by intraosseous and extraosseous neurofibromatosis, which causes normal developmental disorders of local bone. After fracture, it also affects the repair of fractures and causes pseudoarthrosis. Boyd reports 14 cases of congenitality. Among the cases of patellofemoral joints, 9 cases had skin neurofibroma nodules and skin pigment spots, and 17 of 178 cases were reviewed. There were also some cases of some changes in the posterior tibial nerve. There are many similarities between congenital sacral pseudoarthrosis and neurofibroma. At the same time, microscopy of the pseudoarticular joint in some cases is also consistent with neurofibromatosis. These two diseases are undoubtedly closely related.
Fiber abnormal growth factor (40%):
Boyd and Sage (1958) reported 15 cases, two of which were pseudo-joints, showing microscopic proliferation of cells under the microscope, and mentioned that it is related to the disease. In most cases, there are brown spots on the skin, and in the early stage of the pseudo-articular, cystic change zone The bone has a curved deformity, and even some cases have large clitoris, which is similar to the third type of fibrous abnormal proliferation, Albright disease, X-ray manifestation, in the pseudo-articular area is the cystic variable area in the early stage or the residual cystic area It is frosted glass-like, and the disappearance of trabecular bone is similar to the proliferation of fibrous abnormalities. More importantly, the local pathological changes are quite similar. From the above relationship, there is a closer relationship between the two.
Neurological factors (10%):
Aegerter (1995) proposed that neurofibroma, fibrous heterogeneous proliferation and congenital sacral pseudoarthrosis have many things in common, which may be caused by a common cause of fibrous tissue misfolding, and the poor transformation and disorder of these fibrous tissues The normal growth and maturation of the bone in the local area appears incompetent. The reason for this change may be that the local nerve pathway is abnormal. In the case of 78 cases of congenital malformation in Moore, 91% of the cases had pathological changes in the peripheral nerves, supporting This kind of neurology.
(two) pathogenesis
Many scholars believe that congenital sacral pseudoarthrosis is associated with neurofibromatosis, because patients can have typical neurofibromatous subcutaneous nodules on the skin at the same time. These fibroblastic masses are due to changes in the nerve path in this area. Growth abnormalities, thickened periosteum and thick fibrous tissue sleeves at the pseudoarticular joints, McElvenny believes that this hamartomatous proliferative soft tissue will impede bone formation and normal osteophyte growth, thick fiber loops Compressed bone tissue, reducing blood supply, causing bone atrophy, according to the pathological observation of Boyd, it is considered that the pathological change of type II is an invasive osteolytic fibromatosis. The younger the patient, the greater the invasiveness. With the increase of age, its invasiveness is also reduced, and when the epiphyseal plate is closed, this fibromatosis also loses its invasiveness. Therefore, even in the whole growth age, even if there is a bone connection, a pseudoarticular joint will occur. Do not easily make a cure before puberty.
Prevention
Congenital sacral pseudoarthrosis prevention
The disease is congenital disease, no effective preventive measures, early diagnosis and early treatment is the key to the prevention and treatment of this disease, but this disease needs attention, the treatment method varies from person to person, can not be uniform; for conservative treatment of infants and young children is better, do not Easy osteotomy or orthopedics, pathological or early scraping of bone grafts, excessive surgical treatment will lead to serious consequences.
Complication
Congenital patellofemoral joint complications Complications, nausea and vomiting
First, the complications caused by the disease itself:
Once the pseudoarthrosis is formed, the child can't walk with heavy weight. The longer the time is, the more severe the symptoms are. The worsening of the calf deformity sometimes presents with "continuous sputum". Frequent fractures often occur in adolescence, and even some cases have infections due to puncture of the skin at the fracture end.
Second, postoperative complications:
(1) Because the child with this disease needs general anesthesia during treatment, nausea and vomiting often occur after general anesthesia. The longer the anesthesia time, the higher the incidence of vomiting. Therefore, the general anesthesia is not awake before going to the pillow. The head is biased to one side to prevent aspiration due to vomiting.
(2) Children have poor tolerance to blood loss. When blood loss is excessive, they often show pale and bloody wounds. At this time, timely symptomatic treatment should be given.
Symptom
Congenital patellofemoral joint symptoms Common symptoms Tibial pseudoarthrosis formation of joint deformity pigmentation spots
The typical congenital sacral pseudoarthrosis is the anterior bending deformity or pseudo-articular shape of the 1/3 of the calf of the child. The patient's calf is shortened, thin and thin, and the middle and lower segments are angularly deformed, prone to fracture, and not healed after treatment. The formation of pseudo-articular joints can also be fractured at birth. The children generally have no swelling, pain, discomfort, and the skin is often scattered with light brown spots.
According to the shape of the tibia, it is generally divided into three types in clinical practice.
(1) Bending type: the lower part of the humerus is bent forward after birth, but there is no pseudo-articular joint. The cortex of the anterior arch of the tibia is thickened, the medullary cavity is occluded, and the humerus end is atrophied and hardened. It has a shape of the anterior arch. After the fracture occurs, it is not treated by general treatment. Healing, forming a pseudo-joint, or because of the disease is not known, rushing for osteotomy, forming non-healing, continued development and absorption at both ends, hardening of the end of the bone, further atrophy and thinning at the distal end, showing a pen tip.
(B) cyst type: cystic changes in the lower third of the humerus after birth, but the backbone is not fine, clinically difficult to find, slight external force caused by non-union after fracture, followed by the formation of pseudo joints.
(3) Pseudo-articular type: After birth, the defect of the middle and lower part of the humerus is found, and the pseudo-articular joint is formed. The pseudo-articular joint is connected with hard fibrous tissue or cartilage. The bone end becomes thinner with the growth and development, atrophy, and the distal end is more obvious. It is pen-like, with a thin cortex and sometimes atrophy around the soft tissue, including the gastrocnemius. If the tibia is involved, the same changes occur.
There is another way, Boyd divides the disease into six types:
Type I: There are pseudo-articulars at the same time as the frontal bend. There are some defects in the tibia at birth, and there may be other congenital malformations.
Type II: There are pseudo-articulars at the same time as the frontal bend. There are gourd-like stenosis at the time of birth. There may be spontaneous fractures or minor injuries before the age of 2, which are collectively called high-risk humerus. The bones are cone-shaped, round and hardened. Myeloid occlusion, this type is most common, often accompanied by neurofibromatosis, the worst prognosis, in the growing season, fracture recurrence is very common, with the increase in age, the number of fractures will be reduced, until the epiphysis is mature, fractures no longer occur .
Type III: pseudoarthrosis occurs in congenital cysts, usually at the junction of 1/3 and 1/3 of the humerus. It can have a anterior curve and then a fracture. The chance of fracture after treatment is less than that of type II.
Type IV: There is a hardening segment at the junction of 1/3 and 1/3 of the humerus, and a pseudoarticular joint occurs. The medullary cavity is partially or completely occluded. Incomplete fractures or marching fractures may occur in the tibial cortex. Healing, the fracture is widened to form a pseudo-articular joint. The prognosis of this type of fracture is good, and the treatment is better before the fracture is mature.
Type V: In the case of dysplasia of the tibia, the tibia produces a pseudoarticular joint, and the pseudo joints of the two bones can occur at the same time. If the lesion is limited to the tibia, the prognosis is good. If the lesion develops to form the sacral pseudoarticular joint, the development process is similar to type II. .
Type VI: pseudoarthrosis caused by intraosseous neurofibromatosis or Schwannoma, which is rare, and the prognosis depends on the invasiveness and treatment of intralesional lesions.
Examine
Congenital sacral pseudoarticular examination
The main cause of the disease is X-ray examination: X-ray film can be seen in the humerus, the lower 1/3 anterior curve, angulation, fibrocystic and pseudoarticular formation, thinning of the bone end is conical, bone end hardening medullary cavity atresia, The cortical bone is thinned, the bone is atrophy, the articular surface of the distal radius can be deformed, and the humerus can have pseudo-articular changes or bending deformities, and the calf can be shortened. If necessary, CT or MRI can be used as a supplement.
Diagnosis
Diagnosis and diagnosis of congenital sacral pseudoarthrosis
diagnosis
Mainly according to the unilateral calf in the lower third of the 1/3 of the forward bending deformity, no serious history of trauma, most children with scattered skin-like pigment spots or nerve fiber nodules, combined with X-ray findings can be diagnosed.
Differential diagnosis
1. Fracture nonunion: traumatic tibial fracture in children, malunion can occur, and fracture nonunion is extremely rare, even if there is no healing, there will be a large number of callus formation in the fracture.
2. Brittle bone disease: The disease is a systemic disease with multiple fracture history. Although it is easy to fracture and repair and is barrier-free, in addition, the disease has special symptoms such as blue sclera, hearing impairment, and secondary sexual characteristics. Early appearance and family genetic history.
3. Rickets: The long bones of the extremities have changes. The lower extremities are mostly bilateral due to the weight-bearing knee varus deformity. The X-ray shows that the metaphysis is widened, the sacral line is widened, and there is a cup-like change. The rickets can be cured. Left temper varus deformity, X-ray showed thickening of the backbone, thickening of the medial cortex of the tibia, but no obvious osteosclerosis, medullary cavity.
