| Objective: Femoral head necrosis was so common and refractory diseasein the field of orthopaedic, happened at30to50years old in young andmiddle-aged people,because the disease etiology, pathogenesis was unclear inclinical treatment,it brought huge difficulties. For patients with femoral headnecrosis, early head treatment was crucial, but inappropriate treatment madethem be at risk of collapse of the femoral head at any time, in turn, had to takehip replacement. The treatment method of the femoral head were many atpresent, according to femoral head necrosis in different stages, often adopteddifferent operation programs, the basic treatments can be divided into twocategories, protecting head treatments and joint replacement, and protectinghead contained many surgical treatment, such as S-P incision femoral headwindowing decompression and bone graft and some of the minimally invasivesurgery. Along with the development of the times and the progress of medicaltechnology, minimally invasive treatments which were favoured by patientsand medical staff had become the current direction and trend of surgicaltreatment, such as interventional therapy and the femoral fead marrow coredecompression and bone graft and tantalum rod embedded based on themarrow core decompression, stem cell transplantation, etc. Or two or severalkinds of combination therapy of minimally invasive surgery,.But there werestill some problems, such as the dead bone in femoral head can not thoroughlyand completely removed, thereby affecting the formation of new bone, thebiomechanics supporting of femoral head interior was abate, increased the riskof a collapse of the femoral head.Now a new type of femoral head surgicalinstruments like eccentric bit was designed and developed in order to prove itsfeasibility to take a smaller trauma, more simple and rapid operation,effectively cleaning the dead bone in femoral head, implanting a object,whichi was an active and had a role in mechanical support.Methods: a total of20cases of normal femoral head specimens,8caseswere the left side,12cases were the right side; male femoral head specimensof13cases,female femoral head specimens of7cases, after numbered,retained the preoperative imaging information.First of all specimens offemoral head was fixed on the test bench, Under C-shaped X-ray machineguiding about2-3cm below the femoral greater trochanter, along the directionof the femoral neck to the usual central of the femoral head necrosis area atthe femoral head cartilage bone under5mm,a kirschner wire was inserted.After accurate positioning around the kirschner wire opened a small bonewindow on the bone cortex; along the needle with hollow drill bone artifactsthe femoral head was expanded medullary cavity and reduced pressure andbuild bone channel; exited bone artifacts, with a push rod launching forwardtook bone tissue in bone artifacts for bone graft. Along the bone channels asix-gears eccentric bit was inserted during the first gear, connected power drill,cut femoral head. After satisfied under the C-shaped X-ray machinemonitoring, by adjusting the gears control area gradually increaseed gear tosix, forming the cavity within the femoral head, and then cleaned the femoralhead bone tissue removed, rinsed completely. Using femoral bone graft device,under the c-shaped arm X-ray machine monitoring, inserted softly thedrivepipe along the bone tunnel to femoral head cavity, and didn’t touch thecavity wall of the femoral head. According to the femoral head cavity volumeand the quantity of autologous bone, adding suitable amount of allograft,through the drivepipe, useed the push rod to push the bone tissue into the bonecavity, cemented. Observing through the windows of the drivepipe in theprocess of bone graft, completely pushed the bone tissue which attached to thewall of the drivepipe into the bone cavity, made full use of the bone tissues,reduced the waste of bone tissues. Afte satisfaction by perspective,measureddecompressed bone channel length, embedded processing good fibulasegment allograft, was apart from the femoral head cartilage under5~l0mm.Retained imaging datas, took off the femoral head from the laboratory bench, using pendulum saw saw off the femoral head and then put the femoral headinto the measuring pot with a certain amount of water, watching the water rise,record the rise volume, which was expressed in A,the volume of femoral head.And then used the pendulum saw on the coronary basic to make the femoralhead divided into two, cleaned internal bone tissue, with vernier calipersmeasured the most thin thickness of the subchondral bone of femoral head,which was expressed in D. Put the emptied femoral head once again into themeasuring pot with a certain amount of water, watched the water rise,recorded the rise volume, the volume for the remaining of the femoral headexpressed in B, then A-B was the volume of the cavity of the femoral head,expressed in C. The20cases of femoral head were operated like that, andcalculated the femoral head clearance volume ratio (C/A) average, andfemoral head cartilage bone thickness D under the average, both estimated therange of the overall mean.Results:20cases of femoral head specimens were successfullycompleted, the image date about the femoral head cleared-volume as thechange of gear was increased gradually, after the bone graft imaging effectwas good, the femoral head cleared-volume averaged40%between the ARCOfemoral head necrosis in installment standard of15%and30%, the thicknessof the subchondral bone of femoral head at the top5-8mm, with an average of6.5mm was greater than the limit value of the subchondral bone of thefemoral head5mm causig collapse of the femoral head.Conclusion: femoral head eccentric bit surgical instruments, were simplyoperated, can thoroughly and minimally invasive clean the dead bone infemoral head, proving its operability and feasibility. For further clinicalapplication provideed with reliable and credible basis and for femoral headnecrosis with protecting head treatment provideed a new idea and treatmentoptions. |
PDF Full Text Request