Current attitudes to cementing techniques in British hip surgery

Transcription

1 Ann R Coll Surg Engl 1994; 76: Current attitudes to cementing techniques in British hip surger Aresh Hashemi-ejad FRCS Orthopaedic Senior Registrar icholas C Birch FRCS Orthopaedic Senior Registrar icholas J Goddard FRCS Orthopaedic Consultant Orthopaedic Department, The Roal Free Hospital HS Trust, London Ke words: Hip surger; Cementing technique; Prostheses Aseptic loosening is the major problem in hip joint replacement. Improved cementing techniques have been shown to improve the long-term survival of implants significantl. To assess the use of modern cementing techniques in British surgeons, a detailed questionnaire was sent to all Fellows of The British Orthopaedic Association (BOA) regarding cement preparation, bone preparation, cementing technique and prostheses used in total hip arthroplast. Excluding retired fellows, surgeons who use no cement, and those who had filled in forms inadequatel, 668 responded, who between them performed hip arthroplasties per ear. In this surve, 21 different tpes of hip prostheses were implanted b the surgeons; 48% of hips implanted were Charnle tpe. Of the surgeons, 46% used Palacos with gentamicin as their cement for both the femur and acetabulum. For the femur, 44% of surgeons remove all cancellous bone, 4% use pulse lavage, 59% use a brush to clear debris, 94% dr the femur, 97% plug the femur, 76% use a cement gun and 7% pressurise the cement. For the acetabulum, 88% of surgeons retain the subchondral bone, 4% use pulse lavage, 1% dr the acetabulum, 22% use hpotensive anaesthesia and 58% pressurise the cement. Overall onl 25% of surgeons (26% of hips implanted) use 'modern' cementing techniques. This has implications for the number of arthroplasties that ma require earl revision. Total hip arthroplast (THA) is one of the most successful and cost-effective operations ever introduced, and annuall 8 THAs are done worldwide. Aseptic loosening of the components is the most common longterm complication and constitutes 8% of the revisions (1). Using cementing techniques initiall advocated b Charnle (first generation) the incidence of radiographic loosening of the femoral component was reported to be 3% to 4% at 1 ears (2,3). Using improved cementing techniques with intramedullar bone plugs, cement gun and pressurisation (second generation), the incidence of radiographicall loose femoral components fell to 3% at 11 ears (4). Comparison of patients undergoing THAs using onl a cement gun with improved cementing techniques in a single centre showed a reduction of radiological loosening from 21% at a mean of 4 ears in the first group to no loosening in the group having the improved cementing technique (5). De Lee and Charnle (6) reported a 9% cup migration rate which was associated with a thin acetabular wall. Fowler et al. (7) using a technique that pressurised cement on to clean cancellous bone demonstrated significant reduction in cup migration at 7 and 13 ear reviews. Mulro and Harris (4) showed no change in the incidence of radiographicall loose acetabulum using their improved cementing techniques. We undertook a stud to review the current attitudes to cementing technique in British hip surger. Method Correspondence to: Aresh Hashemi-ejad FRCS, Orthopaedic Departnent, The Roal Free Hospital HS Trust, Pond Street, London W3 2QG To assess the cementing practice of British Orthopaedic Surgeons for primar hip replacement, we posted a questionnaire (Fig. 1) to all 184 Fellows of The British Orthopaedic Association. The questionnaire was in four

2 Cementing techniques in hip surger 397 FEMORAL CEMETIG TECHIQUES 1. Do ou attempt to remove as much cancellous bone as possible? 2. Do ou use pulsed lavage? 3. Do ou use an intra-medullar brush to clear bone debris? 4. Do ou dr the femoral shaft prior to cementing? If 'es' please ring or specif our usual technique -Plug -Swab -Swab + adrenaline? 5. Do ou plug the distal femur? If 'es' please ring or specif our usual technique -Cancellous bone plug -Cement -HDP (eg. Hardinge, JRI) 6. Do ou use a cement gun? 7. Do ou pressurize the cement prior to insertion of the prosthesis? 8. What is our usual femoral component? Please specif: 9. What head size do ou generall use? Please ring or specif mm -25 mm -28 mm -29 mm -32 mm Approximatel how man cemented replacements are done in our name per annum? ACETABULAR CEMETIG TECHIQUES 1. Do ou aim to retain the subchondral bone? 2. Do ou use anchor holes? -"Classical" large ilial, ischial +pubic -Multiple small anchor holes 3. Do ou use pulsed lavage? 4. Do ou dr the acetabulum prior to cementing? Please ring or specif our technique: -Swab -Swab + adrenaline 5. Do ou use controlled hpotension prior to cementing? 6. Do ou pressurize the cement prior to insertion of the socket? CEMET PREPARATIO 1. Which cement do ou usuall use for: The femur? -MW -Simplex -Palacos -Palacos + Gentamicin? 2. Do ou use low viscosit cement? -Acetabulum -Femur 3. Do ou chill the monomer? 4. Do ou centrifuge the cement prior to insertion? 5. Do ou vacuum mix the cement? (ot simple fume extraction) The acetabulum? -MW -Simplex -Palacos -Palacos + Gentamicin? Figure 1. Questionnaire. parts regarding: (1) The prosthesis used; (2) The cement and its preparation, (3) Femoral canal preparation and cementing technique and (4) Acetabular preparation and cementing technique. Results A total of 719 surgeons responded to the surve. Excluding retired fellows, surgeons who use no cement, and those who had filled in forms inadequatel, 668 responded, who between them performed hip arthroplasties per ear (an average of 65 hips per surgeon per ear (range 1-25)). Excluding retired fellows and those who do no hips from the nonresponding group, the surve is representative of 7% of all BOA Fellows performing hip arthroplast. The results of the questionnaire were analsed with respect to the number of surgeons performing the technique and number of hips which underwent a particular practice.

3 398 A Hashemi-ejad et al '%'ofsurgons 4 5 * % of Surgeon * % of Hips 12 E3 -. l V_-RZ-- Ara I _9 O Charnas H Muller. Furlog Exeter moirotm 1 Tpe of Prosthesis Figure 2. Prostheses used. _ Head Sizes (mm) Head sizes used. Figure e 21 _ % ofhips I C * % o Surgeons * %od Hips 1i I - s.- - _ _~~~~~~~~~~~~~~~~~~~I CMW SImplex Palace Pa & Gent Other Tp of Cement Figure 4. Femoral cement used. - CMW Simplex Piaco. PalaeoJ&Gent Other Tpe of Cement Figure 5. Acetabular cement used WS web & Figure 6. E_i... SW s" a PI Dring Technlqui e.... Femoral dring technique.. ofsurgeons * % of Hips 6 mm~~~~ OUw = F%1 Figure 7. C llwll HDP Tpe Of Plug Femoral distal plug. a % d Surgeons * %o1hips Prostheses used There were 21 different tpes of hip being used b the surgeons. Charnle tpes were used b 5% of surgeons and accounted for 48% of hips implanted (Fig. 2). Of the surgeons, 4% used more than one tpe of hip. Of hips implanted, 49% had mm heads and 28% had 28 mm heads (Fig. 3). Cement preparation Of the surgeons, 6% chilled the monomer, 11% vacuum mixed and 2% centrifuged the cement. In the femur, 26% of surgeons used low-viscosit cement and in the acetabulum 7%. Palacos with gentamicin was used b 49% of surgeons in the femur and b 45% in the acetabulum (Fig. 4 and Fig. 5). Femoral technique Of the surgeons, 44% aim to remove the cancellous bone, 4% use pulse lavage, and 59% use a brush to clear the debris; 94% of surgeons dr the femur (Fig. 6), most commonl using a swab; 97% plug the distal femur (Fig. 7), most commonl using a high densit polethlene implant; 76% use a cement gun and 7% pressurise the cement. Acetabular technique The subchondral bone was retained b 88% of surgeons (in 82% of hips implanted). All surgeons use anchor holes (Fig. 8) and all dr the acetabulum (Fig. 9); 4% of surgeons use pulse lavage and 23% use hpotensive anaesthesia; 58% pressurise the cement in the acetabulum.

4 Cementing techniques in hip surger g l %of Surgeons s...*...o...u.r o. 2 _ -- 24_, Discussion Classical Multiple Tpe of Anchor Hole Other Figure 8. Acetabular anchor holes. There is no great variation in the numbers of hips implanted in a particular wa and the numbers of surgeons performing the different techniques. The number of THAs performed per surgeon per ear reported in this stud seems a little high, and although the numbers reported ma have been exaggerated we feel the techniques reported are not. There is a wide range of hip prostheses available to the surgeon, man of which have no long-term outcome studies. There are 21 tpes of hip imnplanted b the surgeons in this stud, 86% of the hips implanted are Charnle, Howse, Muiller, Furlong, Exeter and Stanmore tpes. The wide variation of prosthesis used has been reported previousl (8), but not the frequenc with which the are used. Of the surgeons, 5% implant Charnle tpe moer hips, ceenin which account tehiqe for 48% (3. ofths hips implanted; moer (third geeain tehiqe inlud usifameu_r th 7% of surgeons implant Exeter tpe hips which account for 9% of hips implanted; 4% of surgeons use more than one tpe of hip as their choice of implant. In the absence of long-term comparative prospective trials it is difficult to know if one prosthesis is better than the other. The biological consequences of particulate wear debris are a cause for concern. Livermore et al. (9) showed that the greatest amount and linear wear occurred with a mm head, the greatest amount and volumetric wear was seen in the 32 mm head and the least amount and linear wear were associated with the use of a 28 mm head diameter, suggesting the best wear characteristics are realised with a mid-range head size. Morre and Ilstrup (1) demonstrated a higher incidence of acetabular loosening with the 32 mm head size compared with the mm component, which has a smaller frictional torque force. This surve showed that 5% of hips implanted are with a mm head. This is a reflection of the high number of Chamle tpes implanted. Onl 25% of surgeons (28% of hips) implanted 28 mm heads. The Wrightington group and others still use Gharnle's original cementing technique and have indeed reported Swaob SWab & Adenafin. Swab & PmxI OUwr Dring Technique Figure 9. Acetabular dring technique. plug, use of a cement gun, cleaning of the intertrabecular spaces (using a brush and pulse lavage), pressurisation and reduction of the porosit of the cement (14). For the acetabulum, pressurisation of cement on to clean cancellous bone demonstrated significant reduction in cup migration (7). Excluding the centrifugation of cement, which is onl performed b 2% of the surgeons in this surve, onl 25% of surgeons (26% of hips implanted) perform these modem 'third generation' cementing techniques. We did note that surgeons who implanted 2 or less hips per ear had different cementing practice to those who implanted more. Onl six out of 15 surgeons in this group undertook modem cementing techniques. This has implications on the potential number of earl failures due to aseptic loosening. We feel the emphasis in hip surger cmneshould socket movein from tota hi implanting replacement. new Clin..Orthop.. designs to improving 7 _olrj,gega_e 196i11_2-2 the cementing techniques J,Ln on SMtried xeinewt and tested prostheses. Exte total hip. relaemn. Ortho Cli ort Am _47-9 References 1 Malchau H, Herberts P, Ahnfelt LE, Johnell. Prognosis of total hip replacement. Results from the national register of revised failures in Sweden-a ten ear follow-up stud of THR. Scientific Exhibition presented at the 61st American Academ of Orthopaedic Surgeons, Stauffer R. Ten ear follow up stud of total hip replacement with particular reference to roentgenographic loosening of the components. J Bone joint Surg 1982; 64A: Sutherland CJ, Wilde AH, Borden LS, Marks KE. A ten ear follow up of one hundred consecutive Muiller curve stem total hip replacement arthroplasties. J Bone joint Surg 1982; 64A: Mulro RD, Harris WH. The effect of improved cementing techniques on component loosening in total hip replacement. J Bone joint Surg 199; 72B: S Roberts DW, Poss R, Kelle K. Radiographic comparison of cementing techniques in total hip arthroplast. J Arthroplast 1986; 1: De Lee JG, Charnle J. Radiological demarcation of

5 4 A Hashemi-ejad et al. 8 ewman K. Total hip and knee replacements: a surve of 261 hospitals in England. J R Soc Med 1993; 86: Livermore J, Ilstrup D, Morre B. Effect of femoral head size on wear of the polethlene acetabular component. J Bone joint Surg 199; 72A: Morre B, Ilstrup D. Size of the femoral head and acetabular revision in total hip replacement arthroplast. J Bone Joint Surg 1989; 71A: Joshi AB, Porter ML, Trail IA et al. Long-term results of Charnle low friction arthroplast in oung patients. J Bone Joint Surg 1993; 75B: Schulte KR, Callaghan JJ, Kelle SS, Johnston RC. The outcome of Charnle total hip arthroplast with cement after a minimum twent ear follow-up. The result of one surgeon. J Bone joint Surg 1993; 75A: Harris WH. One step back, two steps forward. J Bone Joint Surg 1993; 75A: Harris WH, Davies JP. Modem use of modem cement for total hip replacement. Orthop Clin orth Am 1988; 19: Received 7 March 1994