Femoral stem loosening rate of less than 0.16% per year at years 1. Exeter Hip

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2 Exeter Clinical Results Femoral stem loosening rate of less than 0.16% per year at years 1 Exeter Hip Survival of stem 2 CUMULATIVE ESTIMATE OF SURVIVAL (%) AT 18YRS - TAKEN FROM YR RESULTS YEAR POST OPERATION figure 1: Survival estimate at 18 years 93.3% page 2

3 Clinical experience, during the past three decades, indicates that the Exeter stem geometry possesses distinct advantages compared with other designs. DOUBLE TAPER STEM DESIGN POLISHED COLLARLESS 30 YEARS CLINICAL HISTORY CLINICAL EXPERIENCE 62% ENTIRELY RADIOLUCENT LINE FREE AT CEMENT BONE INTERFACE AT YEARS 3 75% SHOWING NO LOSS OF CALCAR HEIGHT AT YEARS 3 NEW INSTRUMENTATION OPERATIVE TECHNIQUE CEMENT PRESSURISATION STEM RANGE PRIMARY/X-CHANGE REVISION TOTAL HIP SYSTEM SIMPLEX CEMENT & ACCESSORIES EDUCATION AND TRAINING page 3

4 Stem Design The success of the Exeter Total Hip System is the result of lessons learned from three decades of clinical experience, research, product development and, surgical and engineering collaboration. The Exeter stem utilises the inherent time dependent properties of bone cement to improve fixation, optimise load transmission and aids the restoration of normal patient anatomy. Stem Fixation As the double tapered, polished, collarless Exeter stem engages, it becomes progressively more stable and secure within the cement mantle. This stem movement is normally accommodated by creep (deformation over time) 4 within the bone cement. Bone cement is strong in compression and weak in tension. The Exeter stem loads the bone cement in such a way that the ratio of compression to shear is greatly increased. figure 2: Load transmission via the Exeter stem The hollow centraliser allows the stem to move distally within the cement mantle, while at the same time preventing end bearing of the stem directly onto the cement. Load Transmission Bone turnover continues throughout the life of the patient. To reduce late loosening, the interface mechanics must be compatible with bone turnover. The reduction of shear forces may be an important part of maintaining this compatibility. The Exeter stem reduces the incidence of late loosening 3 via the double taper transmitting load from the stem through the cement to the cement bone interface. Once the stem is loaded, hoop stresses are set up within the cement mantle (fig 2). As the stem engages creep takes place within the cement mantle and the associated stress relaxation dissipates the hoop stress. Residual strain persists in the cement during periods of relative unloading, thus allowing stress relaxation in the cement to take place. When load is reapplied, there is an increase in the ratio of radial compression to shear stress in the cement, and at the interfaces. Patient Anatomy Offset is critical to the success of a total hip replacement 5. The four offsets within the Exeter stem range allow the surgeon to adjust femoral offset independently of stem size, neck length and leg length. page 4

5 Cup Design Instrumentation Design The Exeter All Plastic Cup range is specifically designed to reduce the risk of dislocation and to aid accurate implant positioning. Tangential skirt geometry UHMWPE cup 165 of head coverage High and low profile options Available in Duration stabilised polyethylene Heads available in Zirconia ceramic or super polished Orthinox 26mm, 28mm and 30mm X-tra cover option Integral x-ray marker around cup margins CDH Cup Option Successful cemented hip replacement depends upon good surgical technique, implant design and a secure and complete cement mantle 6. The new Exeter primary instrumentation is designed for: Creation of a complete cement mantle of optimal thickness Flexible surgical approach Cement pressurisation Accurate and reproducible implant positioning Ease of use Reliability Restoration of normal patient anatomy page 5

6 Case Studies Case Study 1 WM. Presented with ankylosing spondylitis at the age of Pre-operative film 17th March Post-operative film 10th July left hip. Note the lack of any gap proximally between the stem shoulder and cement. 3. Post-operative film 8th February right hip. 4. Thirteen months post-operative film 31st August left hip. Film shows distal migration of the femoral component within the cement of 1mm. 5. Four years post operative film 13th May left hip. Film shows 1.5mm of distal stem migration. In 1976 WM returned to full-time active work years Post-operative film - left hip. 24 years Post-operative film - right hip. Left acetabular cup was revised in 1986, by use of bone grafting and plating. There was lysis at time of revision in the calcar region, associated with wear debris from the grossly loose cup. Distal migration of the stems within the cement has stopped, when compared to the four year film of the left hip, demonstrating that this migration is a self limiting process percentage 20 Aseptic Stem Loosening 7 percentage 60 Endosteal Bone Lysis in the Femur Muller McKee Charnley Muller Charnley Charnley Follow-up in years 10 Years 12 Years 15 Years 20 Years Exeter 0 McKee Charnley Follow-up in years 10 Years 14 Years 16 Years Exeter page 6

7 Case Studies Case Study 2 DM. This patient was in her mid seventies and classified as being very active. 7. Post-operative film. Implantation of an Exeter Universal hip stem with the distal cement centraliser. Note: The position of the stem within the centraliser and the lack of any gap proximally, between the shoulder of the prosthesis and cement months. There has been about 1mm of distal stem movement within the stem centraliser, this corresponds with a 1mm gap above the shoulder of the stem between the stem and cement Case Study 3 PS. Age 78 Classified as very active. 9. A McKee-Arden hip which had been implanted for some time failed in There is evidence of some bone lysis and considerable granuloma. During the revision procedure, the stem was removed including all fibrous membrane and granuloma. The canal was thoroughly cleaned. Allograft bone chips were packed into the femur using an oversized Exeter stem to impact the bone chips in the canal, the stem was removed, the cavity filled with cement and a slightly smaller stem inserted (11th November 1987) This 3 months postoperative film clearly shows the cement mantle and distal stem centraliser. The areas of bone lysis are still clearly visible. 11. (14th July 1989) 2 years post-operative. All lytic regions have healed, the cement mantle is still clearly visible and there has been about 1mm of distal stem movement within the centraliser. There is also evidence of an increase in bone density in the area of the calcar, and of cortical bone in the region of the mid stem. There is no evidence of the previous lysis. 12. (11th October 1994) 7 years post-operative percentage Radiolucent Lines in the Femur 7 percentage 25 Loss of Calcar Height 7 Greater than 2mm Charnley Charnley Follow-up in years Exeter 0 Charnley Harris Follow-up in years Exeter 15 Years 16 Years 5 Years 12 Years 13 Years page 7

8 Surgical Technique Highlights* Acetabulum 1. Pre-operative Planning: Pre-operative templating is important to select the correct implant sizes, their positions and the minimum cement mantle thickness required. Any surgical approach can be used, and where appropriate, it is important that the patient is firmly and accurately supported in the lateral decubitus position. 3. Acetabular Preparation The acetabulum is reamed to reveal bleeding subchondral bone (trabecular bone where possible). After removing any osteophytes, fixation pits are made with a 10mm drill bit or gouges. These can be supplemented by smaller drill holes where appropriate. Trial cups are inserted to select the cup which will give a minimum of 2mm of cement mantle. After lavage, the bone should be dried to provide a sound key for the cement. 4. Acetabular Cementing Simplex cement is pushed into the acetabulum and pushed firmly into the fixation pits. The acetabular pressuriser is placed over the cement and inflated to create a seal. It is pushed onto the cement to counter the bleeding pressure and to force cement into the bone. Please see cement panel for typical setting times. 2. Neck Resection Full exposure of both the acetabulum and the proximal femur is necessary to prepare, cement and implant the components. As the Exeter stem has no collar, the level and orientation of neck resection is not critical. Once the neck has been resected a full capsulotomy is performed. 5. Cup Insertion The acetabular cup is placed on the introducer. When the patient is in the lateral decubitus position, the shaft is held so that the long alignment rod is vertical and the short one horizontal and perpendicular to the patient s long axis. Rotating the handle of the introducer will place the skirt in the desired position. The cup is implanted when the cement is viscous enough to resist back bleeding pressure and is held in place with the cup pusher until the cement is completely set. page 8

9 Femur Cement It is important to note that different types of bone cement set at various timescales and the temperature of the operating theatre also effects the setting time. Acetabular Cementing Typically using Simplex bone cement with a theatre temperature of 21 C, cement injection and pressuration should take place 6 8 minutes after commencement of mixing. Femoral Cementing Typically using Simplex bone cement and with a theatre temperature of 21 C, the cement should be inserted into the cavity at minutes after commencement of mixing. The Femoral Component should never be positioned so that the lowest of the marks on the anterior and posterior aspects at the base of the neck lie above the level of the cement. 8. Plug Introduction The correct intramedullary plug size is selected by using:- a) flexible reamers of increasing size or b) Exeter plug trials. The corresponding sized plug is implanted to provide a firm seal for pressurising the cement. The femur is then cleaned with lavage and brush to provide a clean dry surface prior to Simplex cement injection. 6. Femoral Preparation The femur is prepared by using the tapered reamers, Capener long-handled gouge and the appropriate rasp/broach selected during the pre-op templating. This creates a cavity which will hold the stem with a complete cement mantle of at least 2mm around it. The rasp/broach corresponding to the template considered appropriate for the femur should be used. It is a serious mistake to over-rasp/broach the canal and remove too much cancellous bone. 9. Femoral Cementing After retrograde filling with Simplex cement, the spout of the gun is cut off at the seal, and the seal is then forced onto the end of the femur to form a closed cavity appropriate for pressurisation. The remaining cement is injected and the pressure maintained until immediately prior to stem insertion. Please see cement panel for typical setting times. 7. Trial Reduction The appropriate head/neck trial is positioned onto the rasp/broach. A trial reduction will verify the correct stem size, offset and position. 10. Stem Introduction With the centraliser in place, the stem is inserted in one continuous smooth movement down the centre of the femur. During insertion pressure is maintained by the thumb placed medially over the area of the calcar. The stem can be inserted through the stem seal to its final position, or the seal can be positioned after the stem is inserted, and held in place until the cement polymerises. page 9 * These are highlights of the full operative technique. Please refer to printed full operative technique for further details.

10 Implant Information CENTRAL RANGE ORTHINOX FEMORAL STEMS STEM RASP ACETABULAR CUP RANGE ALL PLASTIC CUPS IMPLANTS TRIAL CDH Small - 35mm Offset Stem CDH Large mm Offset Stem No mm Offset Stem No mm Offset Stem No mm Offset Stem No.1-44mm Offset Stem No.2-44mm Offset Stem No.3-44mm Offset Stem No.4-44mm Offset Stem EXTENSION TO CENTRAL RANGE ORTHINOX FEMORAL STEMS STEM RASP 30mm Offset Stem (AP1) mm Offset Stem (AP2) No mm Offset Stem No.5-44mm Offset Stem No.6-44mm Offset Stem No.3-50mm Offset Stem No.4-50mm Offset Stem No.5-50mm Offset Stem No.6-50mm Offset Stem mm Tapered Long Stem mm Long Stem mm Long Stem mm Long Stem mm Long Stem ORTHINOX FEMORAL HEADS IMPLANTS TRIAL FEMORAL HEAD 22mm FEMORAL HEAD 26mm -3mm NECK FEMORAL HEAD 26mm FEMORAL HEAD 26mm +5mm NECK FEMORAL HEAD 28mm -3mm NECK FEMORAL HEAD 28mm FEMORAL HEAD 28mm +5mm NECK FEMORAL HEAD 30mm -3mm NECK FEMORAL HEAD 30mm FEMORAL HEAD 30mm +5mm NECK FEMORAL HEAD 32mm -3mm NECK FEMORAL HEAD 32mm FEMORAL HEAD 32mm +5mm NECK CDH 22 x 40mm CDH 26 x 40mm mm Cups LOW PROFILE 44mm LOW PROFILE 48mm LOW PROFILE 52mm LOW PROFILE 56mm HIGH PROFILE 44mm HIGH PROFILE 48mm HIGH PROFILE 52mm HIGH PROFILE 56mm mm Cups LOW PROFILE 44mm LOW PROFILE 48mm LOW PROFILE 52mm LOW PROFILE 56mm HIGH PROFILE 44mm HIGH PROFILE 48mm HIGH PROFILE 52mm HIGH PROFILE 56mm mm X-TRA Cover Cups X-TRA L/P 44mm X-TRA L/P 48mm X-TRA L/P 52mm X-TRA L/P 56mm X-TRA H/P 44mm X-TRA H/P 48mm X-TRA H/P 52mm X-TRA H/P 56mm ZIRCONIA CERAMIC HEADS IMPLANTS TRIAL Femoral Head 28mm Femoral Head 28mm + 5mm neck Femoral Head 32mm - 3mm neck Femoral Head 32mm Femoral Head 32mm + 5mm neck EXETER INTRAMEDULLARY PLUGS IMPLANTS 6mm Dia mm Dia mm Dia mm Dia mm Dia mm Dia mm Dia mm Dia Plug Trials Set page 10

11 New Instrumentation EXETER UNIVERSAL STEM INTRODUCER LEG LENGTH GAUGE TAPER PIN REAMER SMALL TAPER PIN REAMER LARGE EXETER PLUG INTRODUCER ADAPTOR FOR 6MM AND 8MM I.M. PLUGS EXETER BONE LAVAGE SYSTEM RASP INTRODUCER CUP INTRODUCER EXETER ACETABULAR PRESSURISER SPARE BALLOON LATERAL CUP INTRODUCER INTRAMEDULLARY BRUSH 10 PACK UNIVERSAL CUP PUSHER GOUGE:REVERSE CROOK REAMER HANDLE HUDSON CONNECTION REAMER HANDLE AO TIP CONNECTION ACETABULAR REAMER 40MM MM MM MM MM MM MM MM MM MM MM STEM SEAL BACKING PLATE STEM SEAL SMALL 5 PACK STEM SEAL LARGE 5 PACK PROXIMAL FEMORAL SEAL BACKING PLATE PROXIMAL FEMORAL SEAL SMALL 5 PACK PROXIMAL FEMORAL SEAL LARGE 5 PACK GOUGE:HALF CROOK GOUGE:FULL CROOK GOUGE:DOUBLE CROOK FEMORAL LEVER GLUTEUS MEDIUS RETRACTOR CAPSULOTOMY SCISSORS ANTERIOR RETRACTOR INFERIOR RETRACTOR SHORT BLUNT RETRACTOR RASP TRAY CEMENT GUN MK. II PRIMARY CEMENT SYRINGE SURGICAL SIMPLEX P RADIOPAQUE BONE CEMENT 10 BOX DISPENSER CARTON ANTIBIOTIC SIMPLEX BONE CEMENT 10 BOX DISPENSER CARTON page FEMORAL INSTRUMENT TRAY FEMORAL INSTRUMENT TRAY ACETABULAR INSTRUMENT TRAY ACETABULAR INSTRUMENT TRAY GENERAL INSTRUMENT TRAY

12 REFERENCES 1. Prof R.S.M. Ling Clinical experience with primary cemented total hip arthroplasty ; Chir. Organi Mov., LXXVII Prof R.S.M. Ling The History and Development of the Exeter Hip ; A.J. Timperley, G.A. Gie, A.J.C. Lee, R.S.M. Ling The Femoral Component as a Taper in Cemented Total Hip Arthroplasty ; JBJS 1993, 75-B, Suppl. 1: Dr A.J.C. Lee et. al. Time-Dependent Properties of Polymethylmethacrylate Bone Cement ; Proceedings of the Implant Bone Interface Society. Chapter 12 Edited by John Older F.R.C.S. Springer Verlag, B.J. McGrory, B.F. Morrey, T.D. Cahalan, K.N. Ann, M.E. Cabanela. Effect of Femoral Offset on Range of Motion & Abductor Muscle Strength after Total Hip Arthroplasty. JBJS (B) 1995: 77: R.S.M. Ling Cementing Techniques in the Femur ; Techniques in Orthopaedics, Vol. 6, No.3, September A.J. Timperley The Long Term Results of THA ; Data on file Years of the Exeter Hip Ceramic Uncemented Hips - Porous Coating - Hydroxyapatite 1980 Impaction Grafting with the Exeter stem Charnley Metal on Plastic Hip Simplex Bone Cement Moore & Thompson Hemi-arthroplasties 1950 McKee Metal on Metal Hip 1960 Muller Hip Debates on cement ( cement disease ) 1970 Exeter Hip Ling/Lee Exeter Lavage System Exeter Cementing Techniques Impaction Grafting, Socket Nijmegen 2001 Stryker Corporation. Stryker, Simplex, Duration, Orthinox, X-change and Exeter are trademarks of Stryker Corporation. All rights reserved. This brochure and its contents are the copyright of the Stryker Corporation and any reproduction thereof shall be forbidden unless expressly authorised by the Stryker Corporation. The Exeter bone plug is approved in the U.S. for cement use only. Printed in the UK. EH01 1E 03/00 BEN11216 CHP Stryker Europe Stryker House Hambridge Road Industrial Estate Hambridge Road Newbury Berkshire RG14 5EG Tel: +44 (0) Fax: +44 (0)