Necrosis of femur head

The necrosis of head of femur is also known as ischemic and aseptic necrosis of femur head, the main cause is slowing of blood supply (ischemia) or stoppage of blood supply (stagnant/ stasis) which resulted in insufficiency of blood supply to the particular area--degeneration pathological changes. The bone has a few active substances (including osteocytes, marrow, blood-forming elements and adipocytes) which their death will intrigue pathological developments. The ischemic necrosis is not limited only to the femur head, moreover, due to prolongation of the heavy load on its surface, it will cause collapsing of the joint s articulate surface and finally resulted in the degeneration of the hip joint.There are variety of pathologic factor of the necrosis of femur head, the few main types are such as:(1) Wound factor. For example, external impact causes fracture of the femur s neck or dislocation of the joint, sprain injury and etc. Wound is the main factor causing necrosis of femur s head. But whether the wound type of ischemic necrosis should happen or not and the surface involved are depend on the degree of vascular damages and the ability of collateral blood supply substitution. Undoubtedly, different types of external injury leads to bone s vessels or femur head s vessels to be distorted, ruptured or compressed and these will induce the necrosis of femur head. The clinical manifestations include scar of bone fracture, dislocation of femur head, atrophy of lower limb muscle, cripple movement, pain during heavy load and so on. (2) Drug factor. For example, taking of hormonal drugs due to tracheitis, asthma, rheumatism, neck shoulder legs and waist pain, diabetes, skin illness and so on. Previous saying that, massive or long term intake of hormonal preparations leads to its accumulation in the organism and causes pathological changes. While recently, peoples think that necrosis of femur head is directly related to the type, dosage, route of introduction of hormonal preparations; and indirectly proportional to amount and duration of their intake. But long term massive of hormones intake or daily overdosage, sudden fluctuation (increase or decrease) of dosage are few factors of femur head necrosis. Basically, the symmetrical hormonal type of femur head necrosis is more common, more than half of patients have one-sided necrosis and after several months -- the other side. The clinicla manifestations are pain and edema in hip joint, prolongation of faint, dullness in chest, limited function of the lower extremities and so on.(3) Alcoholic factor. Chronic alcoholism is a important attribute despite of other possibility causes. It is because long term of excessive alcohol intake will cause its accumulation in the blood thus injuring the liver -- steatosis, alcoholic hepatitis and cirrhosis. The elevation of lipids in the blood causes the increasing of blood viscosity, then, decreasing of blood velocity and followed by changes in blood coagulability; thus, it might cause blockade, hemorrhage or fat embolism in the blood vessels and lastly resulted in the bone necrosis. The clinical features aggravate after the intake of alcohol -- duck walk, heart insufficiency, general weakness, abdominal pain, nausea, vomitting and so on. (4) Weather (wind, cold and damp). The clinical features are such as pain in hip joint, mostly with cold dampness and difficulty in squating.(5) Insufficiency of liver and kidney. The signs are cachexia, yellowish face, impotent, premature ejaculation, multi- dreams, wet dream, feels weak and so on.(6) Osteoporosis. The signs are feeling of weakness in lower extremities, regional pain, inability to carry load, bones easy to fracture and so on.(7) Flat hip. The clinical features are duck walk, short lower limb, atrophy of muscles, intense of pai after 50m walk, limited ability and so on.(8) Abnormal proliferation of bone marrow. The signs are coldness in limbs, muscular pain, inability to carry heavy load, prone to bone fracture, significant of bone atrophy and so on.(9) Bony tuberculosis with necrosis. The signs are positive tuberculin test, subfebrile temperature in the evening, localized pain, decreased in weight, increased sweating, feeling of weakness and so on.(10) Post-operative necrosis. Clinically, in bone transplantation, 3 years after blood vessels transplantation, insufficient of bone s blood supply--all these lead to bone necrosis. Besides, there are also femur head necrosis due to pressure-compression, radioactive, blood disease, blood vessels, congenital and etc.The main clinical manifestations are: (1) Pain. The pain maybe intermittent or consistent and intensed during movement or sometimes pain during rest. The cahracter of pain mostly is pricking, dull or discomfort and so on; often irradiates to inguinal region, inner surface of thigh, side of gluteal region and inner part of knee, accompanied with numbness in the affected area. (2) Joint stiffness and limited movement. The patient with affection of the hip joint will have difficulties in stretching, bending, squatting, one cannot stands for long period and shows the duck walk. The early symptoms develop externally and lateral rotation is significantly limited.(3) Cripple movement. The progressive shortening cripple movement is due to pelvic pain and collapse of femur head or late stage appearance of hip joint dislocation. In the beginning, it often appears as periodically cripple and it is more obvious in child.(4) Body signs. Deep compressing regional pain, point pain in adductor muscles, positive results in Allis sign, extension or lateral rotation are limited, shortening of affected limb, muscular atrophy, symptoms of half dislocation and sometimes accompanied by spasm pain.(5) X-ray symptoms. The bony lines are tiny or discontinued and the femur head is swollen with capsule formation, sclerosis, flatten or collapsed.The types of necrosis of femur head are divided into 6 according to the surface involved and its shape, they are:(1) Complete necrosis. It is rarely seen, it means the bone necrosis starts from the edge of the joint. It always has fracture around the neck under the femur head and this can induce complete head necrosis.(2) Wedge-shaped femur head necrosis. The mostly seen; the normal femur head is divided into internal--center of gravity and load, external-- no pressure region. The wedge-shaped necrosis of femur head center means necrosis of the loading region.(3) Semi-lunar shapes femur head necrosis. The possibility of occurence is very high, the bone necrosis normally happens at superoanterior (front and above) of femur head, the dead bony tissue resembled a half-moon shape and the hip joint bends externally like a frog style which is most clearly seen in X-ray examination.(4) Sequestral necrosis of femur head, it is the lightest type, where collapse of femur head does not take place.(5) Central necrosis of femur head.(6) non-vascular necrosis of bone.There are 4 stages of development according to the disease state:I period ( changes in microstructures):The X-ray film shows that the small bridges structure in bearing system of the femur head has improper arrangement, disconnected and the femur head s edge has coarse appearance. Clinically, it may or may not accompanied by locallized slight pain.II period (significant period):The X-ray film shows that the inner structure of the femur head has the shadow of small cysts (encapsuled), the intensity of those cysts are irregular. The bony small bridges structure are disorganized, sparsed or unclear. It may accompanied by tiny collapse, the surface area of collapse that reaulted in pain is 10-30% clinically and there are slightly limited movements and etc.III period (necrosis period)The X-ray film shows bone deformations, incomplete of bone edges, irregular or flat shape, disappearance of bridges structure of bones, non-uniform of bone density, dislocation or increased space between hip bone and femur head, or it has the formation of extra ossification; clinically, one has pain, periodically cripple, limited joint movement (ankylosis), may have different degree of shortening of affected limb and etc.IV period (destruction period)It shows bone deformations, significant changes in its structure, appearance of large or irregular surface of collapse, bony small bridges are abnormal and disappearance of articular space or joint cavity of the hip joint. Clinically--pain, functional disturbances, stiffness with walking difficulties, complete or half dislocation and limiting function of the knee joint as well. In the tradional chinese medicine (TCM) studies, this disease is referred as gu shi (melting and eating of bone). The potential factors of avascular necrosis of femur head according to TCM are osteoporosis due to weak body system, decreased immunity and blood essence insufficiency of liver and kidney. The pathological changes involve liver, spleen and kidney. The kidney are inborn foundation which regulates the marrow; if the kidney is healthy, it can generates marrow and once the marrow is full, the bone will be strong. On the contrary, marrow disturbances can cause its atrophy and loss the ability to regenerate. The liver regulates the storage of the blood elements and has the same source as the kidney, both of them related directly (both are healthy or both disturbed simultaneously), therefore, if the liver is impaired, the blood regulation will be disturbed as well and cause inadequate nutrition to the bone and resulting in bone necrosis. The spleen regulates the blood movement, if the spleen is impaired, inadequate of Qi (include oxygen) will take place and cause hypoxia atrophy of muscles and bones. After appearance of pathological changes, the bone and cartilage are easily injured, disturbances in regulation of blood and Qi , bruises in jing mai (in acupunture: route of vessels), blood movement are disturbed, limbs loss of nutrition and decreased of regeneration ability, thus resulted in necrosis of femur head.[Clinical treatment results]There were 621 cases adopted TCM (among them, 21 cases cessated medicine half way), the remain 609 cases with 568 cases completely recovered, 26 cases shown effectiveness, 12 cases turned out better and 3 cases ineffective.