2003 FORM 10-K ZIMMER HOLDINGS, INC. AND SUBSIDIARIES interchangeable, anatomically designed implants which include several innovative features the Company believes cannot be found in other current systems, including a proprietary  CSTi $^{TM}$ porous coating option for stable fixation in active patients, a deepened trochlear groove to maximize range of motion, and simple to use instrumentation. The  Natural-Knee  Modular Cemented Baseplate was launched in 2003. The baseplate complements the existing system of baseplates and can be used with the primary, revision and constrained femoral components, as well as all  Natural-Knee  tibial insert configurations. The unique  Natural-Knee  Ultracongruent Posterior Stabilizing Tibial Insert provides more flexibility to adjust to the needs of the patient at the time of surgery. The Company believes that the performance characteristics of the  Natural-Knee Ultracongruent Posterior Stabilizing Tibial Insert demonstrates its viability as an alternative to traditional PS designs with distinct advantages. M/G ˛  and  Allegretto $^{TM}$ Unicompartmental Knee Systems. The  M/G  and  Allegretto  Uni systems apply the same flexibility and quality of the Company’s other knee implant products to unicompartmental, or single compartment disease. Both of these systems offer the surgeon the ability to conserve bone by replacing only the compartment of the knee that has had degenerative changes. The  M/G  Uni system’s patented minimally invasive intramedullary instrumentation, as well as its new minimally invasive extramedullary instrumentation, offers accurate alignment, precise cuts and secure fixation that provide surgeons with the ability to accurately and efficiently repair damage to joint surfaces of one knee compartment with predictable, reproducible results through a small incision. The minimally invasive instrumentation for the  M/G  and  Allegretto  Uni systems positions the Company to continue to promote and capitalize on growing trends toward less invasive surgical procedures. The Company has established itself in the use of minimally invasive knee surgery with the development of minimally invasive instruments for the  M/G  Unicompartmental Knee System.  MIS Minimally Invasive Solutions  Mini- Incision Total Knee Procedures and  MIS Quad-Sparing TM Total Knee Procedures have allowed the Company to build upon its industry position by offering surgeons the benefits of  MIS  surgery for their total knee procedures. The  MIS Minimally Invasive Solutions  Mini-Incision Total Knee instruments feature smaller instruments which accommodate a smaller incision and less disruption of the surrounding soft tissues. The  MIS Quad-Sparing  Total Knee Procedure features advanced instrument concepts which allow surgeons to perform the total knee arthroplasty through a 7-10 cm incision without cutting the patient’s muscles or tendons. Prolong $^{TM}$ Crosslinked Polyethylene Articular Surfaces. The  Prolong  polyethylene is a bearing surface material for total knee replacement. The United States Food and Drug Administration (‘‘FDA’’) has approved the claim of ‘‘resistance to delamination’’ for the  Prolong  polyethylene The  Natural-Knee ˛  System. The  Natural-Knee Prosthesis System consists of a complete range of The  NexGen  Osteotomy System offers precise instrumentation to perform a high tibial osteotomy, to restore alignment for active patients with unicompartmental osteoarthritis associated with moderate bone deformities. The  NexGen  Revision knee product line, consisting of the  NexGen Legacy Constrained Condylar Knee ( LCCK $^{TM}$), the Rotating Hinge Knee, and the Cruciate Retaining Augmentable (CRA) revision knee products, is designed with extensive options to accommodate the variable needs in revision procedures. These products accommodate more difficult procedures and are augmentable for bone loss and provide increased constraint for patients with ligamentous instability. During 2002, the Rotating Hinge Knee was added to the line for optimal constraint in more severe cases. The most recent release in the Company’s knee product family is the patented  NexGen  CR-Flex Fixed Bearing Knee, a cruciate ligament retaining system designed with components to provide a greater range of motion for patients who require deep bending in their daily activities. The CR-Flex femoral components, utilizing a patent pending concept, allow the surgeon to adjust component sizing without removing additional bone. individual patient needs while providing surgeons with a unified system of interchangeable components. The  NexGen knee system provides surgeons with complete and versatile knee instrument options, including milling and multiple saw blade cutting instrument systems. The breadth and versatility of the  NexGen  knee system allows surgeons to change from one type of implant to another during surgery, according to the needs of the patient, and to support current surgical philosophies. The ongoing use of  Trabecular Metal Porous Surface $^{TM}$ Monoblock Tibial Components implants in both CR and PS philosophies enhances the Company’s strategy to add new innovative technologies to this prominent brand. Trabecular Metal  materials provide a dramatically higher level of porosity than existing alternatives, are similar in stiffness and friction to natural bone and are believed to be a major advancement in orthopaedic materials. The  Trabecular Metal Porous Surface  technology is currently distributed by the Company under an exclusive distribution and strategic alliance with Implex, but, as described above, the Company is in the process of acquiring Implex and its  Trabecular Metal technology. The  NexGen  Complete Knee Solution  Legacy ˛ Knee-Posterior Stabilized product line provides stability in the absence of the posterior cruciate ligament. The PS capabilities have been augmented through the introduction of the  NexGen Legacy  Posterior Stabilized Flex Knee (the ‘‘LPS-Flex Knee’’), a high-flexion implant that has the potential to safely accommodate knee flexion up to a 155- degree range of motion in some patients when implanted using a specialized surgical technique. 6