الفهرس 
Surgical treatment of arthritic hip jointOnly 14 pages are availabe for public view
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Abstract
AIthoUghtheiutroduction of bonC eementinbip surgery by in:l960)~;had revolutionized total. hip’ al’throp1astythe·
probI._ of.apermanentandasafo fixation of.t4e impbUltto.bonebas .
’yet~.find.adCfinitCsolution(Morscber,4 983) .’
.,·ib;;t~I’EadY.andmid-tennresults .ofartfu.opJaStieswithbone ce~
.,;ar.e:.~rety.s’ati~ctory· .J However.the·l~ term loo~i~ofthe~:imPlit,,_co~ytheneeessity for” revisionstiUs ~ main
’long-term··p-roblem ’. The-reported loosening.ratesraaged from 9% to
6()O~(Gustijo and Pasternak, 1988)
lbe· improvements maliC in recent years in prosthetic materials•
....~deSignandoperating tecbniquesinUStbeconsidered. In particular .
~ .in’tementingteebDUiueS.hve already achieved
lmpli.Wedresults.asweU as the deve~ ofnew bone cement- .
jISbioactiveboDeCementand.carboI1...e•.inforced acrylic cement-
maY,,’’t¥eUcbangethe c\llrent\lut-.look on long-term results with
~~!ofinterest in the use ofbcD-cement (Iiams etal -s. 1982 ;
1986 ;MUJroyandHan1s1990) .:
iCDespitethe ilnprovementin loog-tenn results achieved througll
iimprQVeU1#MJVkinceDl.entingtechniqu:etbs,ebiological,as .wellas, the
roedlani~~JiMjtation,sofPMMAJ1laketemeBtless,fu(ation a suitable
’.<”. C.’_’ .• -, .-. ;. - ..
··alteDl~tive<(Enghet~.,J988) .
The major consideration today in clinical research regarding
total hip arthroplasty is , whether one should abandon cemented
fixation for cementless one? (Rothman and Cohn, 1989) .
Why cemented fixation should be abandoned?
The answer for this question involves several contributing
aspects:
Firstly, the rate of component loosening in the intermediate and
long term follow-up studies was less than satisfactory, and was even
more disappointing in younger patients and in the revision total hip
arthroplasty (Collis 1984 ; Callaghan et aI., 1985 ; Pellici et aI., 1985)
V Secondly, progressive bone loss caused by focal nonseptic
osteolysis observed frequently around loose cemented components of
T.R.A., and occasionally around well fixed cemented components
(Goldring et aI., 1983 ; Gasty et aI., 1986 ; Willert et aI., 1990) .
Thirdly, it has been concluded from a review oflaboratory
studies that PMMA undergoes aging a time-dependent alteration of
it’s material properties . Several studies have emphasized the
degradation of PMMA with time and becomes biologically active, in
a negative sense, with loosening and, to a lesser extent, even in the
absecnce of loosening. Thus, cemented fixation undergoes inevitable
and inexorable deterioration of function starts at time of implantation.
(Hungerfordand Jones 1988) .
FourthLy, it has become clear that generation of particulate
debris from cement and wear of prosthetic surfaces, both plastic and
metallic, inicites a biologic response which induce progressive bone
resorption and consequently loosening of the proshesis .
(Salvati et al., 1992) .
LastlY,when considering the local tissue conditions in most
T.R.A. loosening, a new implant embeded with bone cement may
appear especially hazardous . Extended bone lesions at the cement
contact, and in some cases a suspected indiscernible low-grade
infection may suggest saving as much as possible of the remaining
bone stock to ensure a prompt and easy third operation in case of
flaring infection . A repeat excision of the cement,. especially if
pressurized, would be harmful for the bone and difficult for the
surgeon (Lord et al., 1988) . The high incidence of aseptic loosening
following cemented revision T.R.A has been well documented, and
the range varied from 25% to 51% for femoral component, and from
9% to 37% for the acetabular side (Engh et al., 1988) .
The second question to be answered is
Why cementless fixation?
The impetus for the renewed interest in cementless fixation
have been two concerns : the finite longevity of fixation with cement
as inferred from long-term follow-up studies (Sutherland et al., 1982),
and the high failure rates of cemented revision T.H.A. .
(pellici et al., 1985) .
Cementless fixation was found to be most rewarding, And
offers several potential advantages over cemented ones, including:
reduced operating time, reduced initial trauma to the endosteal bone
surfaces, preservation of bone stock, less foreign material, long-term
interface stability and osteointegration, improved bio-compatibility,
and ease of revision (Walker and Robertson, 1988) .
Regarding the conservation of bone stock; it is a vitally
important principle, especially when considering that cementless
implants are typically used in younger patients where the potential for
revision during the patient’s lifetime is high and the need to keep
reconstructive options open is paramount (Rothman and Cohn, 1989).