| Avascular Necrosis of the Femoral Head(ANFH) which can highly lead to mutilation is seen frequently in clinic work.To reserve hip joint by operation is mainly therapy in its early and middle phase.When patients' condition progesses continuously,they will undergo pain of hip joint,limited activities,dearticulation of femoral head and even osteoarthritis.In this case,hip prosthesis replacement is necessary.This article focuses in 232 clinic cases in which patients are all given hip prosthesis replacement due to ANFH.We make a long-term follow-up which contains age,gender,type of prosthesis,therapeutic effect of operation and analys these dada.Patients ages are 28～76 when hospitalization.Its average is 47.1.Number of total cases is 232(258 hip joints) including 166 males(186 hip joints),66 females(92 hip joints).And 124 patients are involved in the left hip joint,134 in the right,50 in both.The causes of ANFH include obsolete fracture of femoral neck(45 cases/45 hip joints),hormone-related necrosis(88 cases/131 hip joints),idiopathic necrosis(18 cases/18 hip joints).There are 193 stage Ⅲ and 63 stage Ⅳ according to ARCO staging system.In these cases,5 hip joints undergo pure-head replacement,43 undergo bipolar-head replacement and 210 undergo total hip replacement.Our follow-ups last 2～11 years.We give Harris score due to patients' joint function before and after operation and do a statistical analysis:The average score of these joints before operation is 61,while that of the first follow-up after operation is 90.The scores of these three operation methods have no significant difference.But according to the Harris scores (5 and 10 years after operation)by statistical analysis,the therapeutic effect of three type of prosthesis replacement have significant difference.That is,bipolar-head replacement is prior to pure-head one,while inferior to total hip replacement.In clinic work,patients whose complain is hip pain are always in stage Ⅱ,Ⅲ,Ⅳ.Their condition will deteriorate even if we get rid of its causes.As soon as the old are concerned,they will often die of other complications if they lie in bed because of femorl neck fracture or ANFH.So more and more orthopedists hold that it's necessary to replace hip joint early:Even aged patients can get out of bed after three weeks and go back into normal life.We choose prosthesis on the base of patients' general condition,bone condition,geometry form of acetabulum and femorl medullary cavity.The methods to fix prosthesis include replacement using cement,cementless riplacement and mixed replacement.Replacement using bone cement(methyl methacrylate) can conjugate bone and prosthesis.Its effect is reliable,mainly used in aged patients who have osteoporosis.But its mutiple-interface effect,producing wearing granulosum,cytotoxic and allergic effect need to be overcome.The second and third generation of cement greatly improve the longivety of hip joint prosthesis.These techniques improve in the usage,stir,force-smear,cement additive and new type cement.Biological fixation is on the basis that bone trabecula can grow into the micropore of the prosthesis.It has some conditions:(1) bone trabecula can grow and regenerate actively.(2)the form of medullary cavity is exact.(3)Press-fit.(4)surface treatment of micropore-biologic fixation prosthesis.So the patients who has good heath and bone condition ought to take this method.Because the loosing mechanism of acetabulum and femur prosthesis is different,they need different fixation method.Nowadays,this method is the first choise of total hip replacement.This article mentions the complications of hip joint prosthesis replacement due to ANFH and its causes,some factors that affect the therapeutic effect.We get following conclusions:Effect of total hip replacement is the best in ameliorate patients' living condition.Bipolar-head replacement is inferior to THR while prior to pure-head one.When progessing to stage Ⅲ,Ⅳ,THR is the best options.With the improvement of better design of hip joint p... |
PDF Full Text Request