ArComXL Polyethylene: A New Way to Process Highly Crosslinked Polyethylene

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2 TM ArComXL Polyethylene: A New Way to Process Highly Crosslinked Polyethylene Several years ago, our competitors introduced highly crosslinked polyethylene (HXLP). Biomet chose not to follow that path. Questions arose regarding the mechanical and clinical properties of HXLP offered by some of our competitors, many of which have been borne out by clinical reports. 1. Lab testing indicated lower fatigue strength and increased brittleness Lab testing indicated the potential for severe oxidation resulting from certain types of processing methods Short-term retrievals showed evidence of premature surface cracking in some cases. 6 Retrieval analysis of some HXLPs shows evidence of surface cracking and microtears, the cause of which may be attributed to decreased fatigue strength. 12,13 White banding indicative of severe oxidation has been observed in several HXLP retrievals at short-term follow-up. 14 Cracks 2

3 Before ArCom Polyethylene, addressing the performance questions presented in the literature surrounding other HXLP. Crack Growth Resistance (MPa-m^.5) 1.8 ArCom 33 kgy Irradiation ArComXL 50 kgy Irradiation 15 HXLP 50 kgy Irradiation 16 HXLP 100 kgy Irradiation 16 Many highly crosslinked polyethylene processing methods lead to mechanical weakening of the material. The patented processing method of ArComXL maintains higher resistance to crack propagation than 1st generation HXLPs..9.7 TM ArComXL 2 nd generation HXLP addresses the concerns associated with 1 st generation HXLP by providing: High Fatigue Strength Extreme Oxidative Stability Similiar Particle Size to ArCom Polyethylene A Solid Clinical Heritage 3

4 Since 1993, no other attempt at polyethylene improvement has equaled the benefits of isostatic compression molded ArCom Polyethylene. Many orthopedic surgeons regard ArCom Polyethylene as the gold standard among modern polyethylene bearings. ArComXL is the only highly crosslinked polyethylene built on this clinical heritage. ArComXL has demonstrated in laboratory studies a 47% 64% decrease in volumetric Volumetric Wear (mm 3 /yr) 40% Reduction 47% Reduction wear rate, a 30% increase in ultimate tensile strength, similiar wear particle shape and size, and no measurable Conventional Poly 18 ArCom 18 ArComXL 15 oxidation under accelerated aging. 15,17 ArCom Polyethylene 8 Year Clinical Follow-Up Zero Osteolysis % Wear Reduction 18 4

5 36mm heads available with ArComXL liners offer high range of motion and low wear potential. TM ArComXL Polyethylene % Decrease in Volumetric Wear Rate, High Strength, 15, 17 and No Measurable Oxidation. 5

6 ArCom Isostatic Compression Molding: A Consolidated Foundation Step 2: Isostatic water pressure is applied to the sealed flexible tube, which forms the resin into a bar shape. Step 1: Flexible tubes are filled with starting resin and sealed in preparation for water compaction. Step 3: The shaped resin, or green bars, are now 70% consolidated. Heat and more intense pressure are still required for full consolidation. Only Biomet controls all aspects of its polyethylene processing Step 4: Green bars are now packaged in foil pouches, repeatedly flushed with argon gas, and a vacuum is drawn on the foil pouches. Step 5: The vacuum sealed bars are now placed in the hot isostatic compression chamber and are subjected to 10 hours of carefully controlled heat and argon gas pressure. Step 6: Laser candling inspection is used to ensure that ArCom bars pass stringent consolidation standards. Pure, consolidated polyethylene barstock, ready to be machined into ArCom Polyethylene liners or further processed into ArComXL Polyethylene. 6

7 Solid Solid

8 TM ArComXL Processing Steps High Wear Resistance, High Strength, and High Oxidative Stability ArCom Barstock 50 kgy Gamma Irradiation Below Melt Temp. Pre-Heat Solid State Deformation Stress Relief Acetabular Liner Machining Non-Energetic Sterilization Solid State Deformation enables high levels of crosslinking without sacrificing the mechanical strength or increasing the risk of o residual free radicals, a concern with higher doses of irradiation. The entire process Free Radicals takes place below the melt temperature of polyethylene, preserving the mechanical strength. The Solid State Deformation cannon (see page 10) quenches residual free radicals through a low heat process which, unlike other 1 st generation processes, does not involve melting. This Crosslink Bonds Cracks due to Oxidation patented process does not decrease the mechanical strength or change the crystallinity of the polyethylene. 17 Gamma irradiation increases the level of crosslink bonds in polyethylene. This is beneficial to wear resistance, but produces free radicals inside the polyethylene. If left untreated these free radicals may increase the oxidation potential of polyethylene when exposed to air. 8

9 Strength Strength

10 Longitudinal Polymer Orientation (LPO): Directionally Engineered Polyethylene Solid State De Longitudinal Polymer Orientation (LPO). As a result of Solid State Deformation, LPO directionally aligns the polymer chains along the longitudinal axis of the polyethylene barstock. This provides the highest level of mechanical strength in the direction that wear occurs. LPO Directionally Orients the Polymer Chains Along the Longitudinal Axis Provides High Strength in the Direction of Wear Assists in Neutralizing Free Radicals ArComXL is the only HXLP to be Directionally Engineered through LPO 10

11 Direction Direction

12 A Clinical Heritage of Strength, Wear Reduction, and Low Osteolysis ArComXL Polyethylene is the first of the 2nd generation HXLPs to have high mechanical strength and high resistance to oxidation. 60 ArComXL also provides a 47 to 64% reduction in volumetric wear rate over ArCom Polyethylene. 15 Extensive independent testing has been conducted on the mechanical strength of the material and the wear particle size, shape, and distribution all of which are found to be consistent with ArCom Polyethylene. 17 Tensile Strength(mPa) Estimated Number of Particles 4E+11 4E+11 3E+11 3E+11 2E+11 2E+11 1E+11 5E Particle Size (microns) ArComXL ArCom ArCom 33 kgy Irradiation 17 ArComXL 50 kgy Irradiation 17 HXLP 50 kgy Irradiation 20 HXLP 100 kgy Irradiation 21 ArComXL is built on the strength of ArCom Polyethylene, which maintains high mechanical strength specifically in the longitudinal axis compared to other highly crosslinked polyethylenes. 17, 20, 21 ArComXL has similar wear particle shape and size distribution when compared to ArCom polyethylene with a reduction in the estimated amount of particles in the 0.2 to 0.4 micron range. 17 Concerns have been raised about the osteolytic potential of smaller wear particles. 9, 10 12

13 Durability Durability

14 Biomet Orthopedics, Inc P.O. Box 587 Date: 12/04 56 East Bell Drive Warsaw, Indiana USA Biomet Hip Joint Replacement Prostheses ArComXL TM Highly Crosslinked Polyethylene Attention Operating Surgeon Description Acetabular liners are composed of UHMWPE and are manufactured into various designs and sizes. The acetabular liners are utilized with other hip prostheses as part of a total joint system. Total hip joint prostheses include: femoral stems, femoral heads, acetabular shells, and acetabular liners. Components are available in numerous designs and sizes intended for primary and/or revision applications. Specialty components that can be added to the total hip system include: acetabular screws, centering sleeves, and canal plugs. Materials Acetabular Liners ArComXL TM highly crosslinked Ultra High Molecular Weight Polyethylene (UHMWPE) Indications 1. Noninflammatory degenerative joint disease including osteoarthritis and avascular necrosis. 2. Rheumatoid arthritis. 3. Correction of functional deformity. 4. Treatment of non-union, femoral neck fracture, and trochanteric fractures of the proximal femur with head involvement, unmanageable using other techniques. 5. Revision of previously failed total hip arthroplasty. Cemented or uncemented applications. Patient selection factors to be considered include: 1) need to obtain pain relief and improve function, 2) ability and willingness of the patient to follow instructions, including control of weight and activity level, 3) a good nutritional state of the patient, and 4) the patient must have reached full skeletal maturity. Contraindications Absolute contraindications include: infection, sepsis, and osteomyelitis. Relative contraindications include: 1) uncooperative patient or patient with neurologic disorders who are incapable of following directions, 2) osteoporosis, 3) metabolic disorders which may impair bone formation, 4) osteomalacia, 5) distant foci of infections which may spread to the implant site, 6) rapid joint destruction, marked bone loss or bone resorption apparent on roentgenogram, 7) vascular insufficiency, muscular atrophy, or neuromuscular disease. Warnings Improper selection, placement, positioning, alignment and/or fixation of the implant components may result in unusual stress conditions which may lead to subsequent reduction in the service life of the prosthetic components. Malalignment of the components or inaccurate implantation can lead to excessive wear and/or failure of the implant or procedure. Inadequate preclosure cleaning (removal of surgical debris) can lead to excessive wear. Improper preoperative or intraoperative implant handling or damage (scratches, dents, etc.) can lead to crevice corrosion, fretting, fatigue fracture, and/or excessive wear. Do not modify implants. The surgeon is to be thoroughly familiar with the implants and instruments prior to performing surgery. 2. Prior to seating the liner into the shell component, all surgical debris (tissue fragments, etc.) must be removed from the interior of the shell component, as debris may inhibit the locking mechanism from engaging and securing the liner into the shell component. 3. Care is to be taken to assure complete support of all parts of the device embedded in bone cement to prevent stress concentrations, which may lead to failure of the procedure. Complete preclosure cleaning and removal of bone cement debris, metallic debris, and other surgical debris at the implant site is critical to minimize wear of the implant articular surfaces. Implant fracture due to cement failure has been reported. Biomet joint replacement prostheses provide the surgeon with a means of reducing pain and restoring function for many patients. While these devices are generally successful in attaining these goals, they cannot be expected to withstand the activity levels and loads of normal, healthy bone, and joint tissue. Accepted practices in postoperative care are important. Failure of the patient to follow postoperative care instructions involving rehabilitation can compromise the success of the procedure. The patient is to be advised of the limitation of the reconstruction and the need for protection of the implants from full load bearing until adequate fixation and healing have occurred. Excessive activity, trauma, and/ or weight gain have been implicated with premature failure of the implant by loosening, fracture, and/or wear. Loosening of the implants can result in increased production of wear particles, as well as accelerate damage to bone making successful revision surgery more difficult. The patient is to be made aware and warned of general surgical risks, possible adverse effects as listed, and to follow the instructions of the treating physician including follow-up visits. Precautions Specialized instruments are designed for Biomet joint replacement systems to aid in the accurate implantation of the prosthetic components. The use of instruments or implant components from other systems can result in inaccurate fit, sizing, excessive wear, and device failure. Intraoperative fracture or breaking of instruments has been reported. Surgical instruments are subject to wear with normal usage. Instruments that have experienced extensive use or excessive force are susceptible to fracture. Surgical instruments should only be used for their intended purpose. Biomet recommends that all instruments be regularly inspected for wear and disfigurement. Do not reuse implants. While an implant may appear undamaged, previous stress may have created imperfections that would reduce the service life of the implant. Do not treat patients with implants that have been placed in a different patient, even if momentarily. Possible Adverse Effects 1. Material sensitivity reactions. Implantation of foreign material in tissues can result in histological reactions involving various sizes of macrophages and fibroblasts. The clinical significance of this effect is uncertain, as similar changes may occur as a precursor to or during the healing process. Particulate wear debris and discoloration from metallic and polyethylene components of joint implants may be present in adjacent tissue or fluid. It has been reported that wear debris may initiate a cellular response resulting in osteolysis or osteolysis may be a result of loosening of the implant. 1. Acetabular screws are to be fully seated to assure stable fixation and to avoid interference with the acetabular liner component. 14

15 2. Early or late postoperative, infection, and allergic reaction. 3. Intraoperative bone perforation or fracture may occur, particularly in the presence of poor bone stock caused by osteoporosis, bone defects from previous surgery, bone resorption, or while inserting the device. 4. Loosening or migration of the implants can occur due to loss of fixation, trauma, malalignment, bone resorption, and/or excessive activity. 5. Periarticular calcification or ossification with or without impediment of joint mobility. 6. Inadequate range of motion due to improper selection or positioning of components. 7. Undesirable shortening of limb. 8. Dislocation and subluxation due to inadequate fixation and improper positioning. Muscle and fibrous tissue laxity can also contribute to these conditions. 9. Fatigue fracture of component can occur as a result of loss of fixation, strenuous activity, malalignment, trauma, non-union, and/or excessive weight. 10. Fretting and crevice corrosion can occur at interfaces between components. 11. Wear and/or deformation of articulating surfaces. 12. Trochanteric avulsion or non-union as a result of excess muscular tension, early weight bearing, or inadequate reattachment. 13. Problems of the knee or ankle of the affected limb or contralateral limb aggravated by leg length discrepancy, too much femoral medialization or muscle deficiencies. 14. Postoperative bone fracture and pain. Do not resterilize. Do not use any component from an opened or damaged package. Do not use implants after expiration date. Caution: Federal law (USA) restricts this device to sale by or on the order of a physician. Comments regarding this device can be directed to Attn: Regulatory Dept., Biomet, Inc., P.O. Box 587, Warsaw, IN USA, Fax Authorized Representative: 0086 Biomet, U.K., Ltd. Waterton Industrial Estates, Bridgend, South Wales CF31 3XA U.K. The information contained in this package insert was current on the date this brochure was printed. However, the package insert may have been revised after that date. To obtain a current package insert, please contact Biomet at the contact information provided herein. Sterility Prosthetic components are sterilized by exposure to one of the following methods: Ethylene Oxide Gas (EtO) Gas Plasma References 1. Baker, D., et al., Study of Fatigue Resistance of Chemical and Radiation Crosslinked Medical Grade UHMWPE, JBMR 46: , Eberhardt, A., et al., The Effects of Irradiation Level and Resin on Fatigue Crack Resistance in UHMWPE, Society for Biomaterials, Gomoll, A., et al., Quantitative Measurement of the Morphology and Fracture Toughness of Radiation Crosslinked UHMWPE, ORS, Feb Gillis, A., et al., An Independent Evaluation of the Mechanical, Chemical, and Fracture Properties of UHMWPE Crosslinked by 34 Different Conditions, ORS, Feb Muratoglu, et al., Effect of Radiation, Heat, and Aging on In Vitro Wear Resistance of Polyethylene, CORR Number 417, pp , December Jasty, M., Crosslinked Poly Podium Presentation, 4th Annual Symposium on Alternative Bearing Surfaces in TJR, Maui, Hawaii, Sept Ries, M., The New Polys: Bridges too Far? Session XV, Current Concepts in Joint Replacement, Las Vegas, NV May Scott, et al.; Wear Particle Analyses of Conventional and Crosslinked UHMWPE Tested in an Anatomic Hip Simulator, 47 Annual Meeting of the Orthopaedic Research Society, San Francisco, CA Feb Mabrey, J., et al., Comparison of UHMWPE Particles in Synovial Fluid and Tissues from Failed THA, Journal of Biomedical Materials Research 58: , Green, T., et al., Effect of Size and Dose of Bone Resorption Activity of Macrophages by In Vivo Clinically Relevant UHMWPE Particles Journal of Biomedical Materials Research 53: , Halley, D., et al., Recurrent Dislocation After Revision Total Hip Replacement with a Large Prosthetic Femoral Head JBJS pg Vol. 86A Number 4, April Bradford, et al., Wear and Surface Cracking in Early Retrieved Highly Cross-linked Polyethylene Acetabular Liners, JBJS, Vol. 86-A, No. 6, June Edidin, et al., Wear Surface Analysis of Highly Crosslinked Acetabular Liners After Implantation. June 12, Bhattacharyya, S., et al., Severe In Vivo Oxidation In a Limited Series of Retrieved Highly Crosslinked UHMWPE Acetabular Components With Residual Free Radicals, 50th Annual Meeting of the Orthopedic Research Society, Paper No:0276, March Data on file at Biomet. 16. Baker, DA, Bellare, A, Pruitt, L: The Effects of Degree of Crosslinking on the Fatigue Crack Initiation and Propagation Resistance of Orthopedic-Grade Polyethylene. J Biomed Mater Res, 66A: , Data Submitted for publication (Exponent). 18. Head, W., et al., Comparison of Polyethylene Wear in Machined Versus Molded Polyethylene Liners in Ringloc Acetabular Cups, Texas Center for Joint Replacement, Plano, TX. 19. Head, W., et al., Mechanical Properties and Clinical Evaluation of Isostatic Molded ArCom Polyethylene, SICOT, August 2002, San Diego, CA. 20. Greer, K., et al., The Effects of Raw Material, Irradiation Dose, and Irradiation Source on Crosslinking of UHMWPE, ASTM STP 1445: Crosslinked and Thermally Treated UHMWPE for Joint Replacement, Bhambri, S., et al., The Effect of Aging on Mechanical Properties of Melt-Annealed Highly Crosslinked UHMWPE, ASTM STP 1445: Crosslinked and Thermally Treated UHMWPE for Joint Replacement,

16 FDA Cleared Claim Statements Hip Simulator Wear The Biomet ArComXL polyethylene acetabular inserts (Part no.: XL ) tested are isostatically compression molded highly crosslinked components (50kGy gamma irradiated under argon) that are sterilized in air by either gas plasma or ethylene oxide. ArComXL was compared to identical predicate polyethylene liners (Part No ) that were machined from isostatically molded polyethylene that was subsequently gamma sterilized (25-40kGy) in argon. A side 3 /10 6 cycles) for ArComXL (EtO sterilized) when compared to the predicate device. All inserts in this study mate with either a 50 or 52mm acetabular shell, have a standard rim, a 32mm inner diameter, and a 4.75mm bearing thickness. Testing was performed under multiaxial hip joint simulation for five (5) million cycles, using a Paul hip load profile with a maximum load of 2.4kN, 32mm CoCr articulating heads, and a bovine calf serum lubricant. The results of in vitro hip wear simulator tests have not been shown to quantitatively predict clinical wear performance. Abrasive Hip Simulator Wear The Biomet ArComXL polyethylene acetabular inserts (Part No. XL ) tested air by either gas plasma or ethylene oxide. ArComXL was compared to identical predicate polyethylene liners (Part No ) that were machined from isostatically molded polyethylene that was subsequently gamma sterilized (25-40kGy) in argon. After 5 million cycles of hip simulator wear conditions, the Biomet ArComXL (EtO sterilized) polyethylene acetabular insert (Part No. XL ) showed a 64% reduction in volumetric wear rate (109.8 opposed to 309.0mm 3 /10 6 cycles) when compared to the same acetabular inserts fabricated from the predicate polyethylene (Part No ). These inserts mate with either a 50 or 52mm acetabular shell, have a standard rim, a 32mm inner diameter, and a 4.75mm bearing thickness. Testing was performed under multiaxial hip joint simulation for two (2) million cycles, using a Paul hip load profile with a maximum load of 2.4kN, 32mm CoCr articulating heads, and a bovine calf serum lubricant. The results of in vitro hip wear simulator tests have not been shown to quantitatively predict clinical wear performance. Free Radicals The Biomet ArComXL polyethylene material tested is isostatically compression ArComXL was compared to predicate polyethylen The Biomet ArComXL (gas plasma sterilized) material, showed a 94% reduction in the number of free radicals (0.22x10 15 compared to 3.82x10 15 spins/g) versus the predicate polyethylene material. Testing was performed by an independent laboratory using Electron Spin Resonance (ESR). Results of in vitro free radical testing have not been shown to quantitatively predict oxidation resistance. Oxidative Stability The Biomet ArComXL polyethylene material tested is isostatically compression ArComXL was compared to predicate polyethylen The Biomet ArComXL (gas plasma sterilized) material ASTM F , which is designed to simulate several years of shelf-aging in air. In contrast, when the predicate material was removed fro acclerated aging (oxidation index was greater than 1.1 at a depth of 1mm). Further, after acclerated aging the average ultimate load for all three ArComXL axes (gas plasma sterilized) remained higher than the peak load (31% higher; 91.8N vs. 70.2N); whereas, the ultimate load for the isotropic predicate material was significantly less than the peak load (44% lower; 42.6N vs. 75.6N) as measured by small punch testing, ASTM F Mechanical Strength The Biomet ArComXL polyethylene material tested is isostatically compression ArComXL was compared to predicate polyethylene The Biomet ArComXL (EtO sterilized) material showed a 30% increase in ultimate tensile strength (from 47 MPa to 61 MPa) in the longitudinal axis versus the predicate polyethylene material. The tensile testing was performed per ASTM standard D638-02a using Type 5 tensile specimens. This material is intended for the sole use and benefit of the Biomet sales force and physicians. It is not to be redistributed, duplicated, or disclosed without the express written consent of Biomet. ArCom, ArComXL, and RingLoc are trademarks of Biomet Manufacturing Corp. DrivenByEngineering P.O. Box 587, Warsaw, IN ext Biomet Orthopedics, Inc. All Rights Reserved Form No. Y-BMT-905R/041505/M

17 Directionally Engineered Highly Crosslinked Polyethylene

18 For product information, including indications, contraindications, warnings, precautions and potential adverse effects, see the package insert and Biomet s website.

19 Building on the long-standing clinical heritage of ArCom Polyethylene, Biomet is proud to introduce directionally engineered Highly Crosslinked Polyethylene for total hip replacement.