CIS Lesson Plans provide members with ongoing education in the complex and ever-changing area of surgical instrument care and handling. These lessons are designed for CIS technicians, but can be of value to any CRCST technician who works with surgical instrumentation.
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Each lesson plan graded online with a passing score of 70% or higher is worth two points (contact hour). You can use these points toward either your re-certification of CRCST (12 points) or CIS (6 points).
Mailed submissions to IAHCSMM will not be graded and will not be granted a point value (paper/pencil grading of the CIS Lesson Plans is not available through IAHCSMM or Purdue University; IAHCSMM accepts only online subscriptions of the CIS Lesson Plans.
Approximately 400,000 Total Knee Arthroplasties (TKAs; commonly called Total Knee Replacements) are performed annually by orthopedic surgeons, and the number of these surgeries is increasing at five percent each year. They help to relieve pain and improve function from knee joint failure most commonly caused by osteoarthritis. Specialized instrumentation is required for these procedures, and it must be processed by Central Service personnel who have received applicable training to do so. Vendors provide different instruments for different facilities for several reasons including physician preference, the type of procedure performed, and group purchasing organization (GPO) contracts. However, there are sets that include basic instruments used for TKA surgeries, and these will be addressed in this lesson.
Knowledge of several key terms is helpful when discussing TKA instrumentation including:
Prosthetic (artificial) knees generally are comprised of femoral, tibial, and patellar components. To implant them, the surgeon makes an incision over the front of the knee and resects (removes) the distal end of the femur and the proximal end of the tibia to accommodate the prosthesis. The patella is exposed using retractors such as Chandler bone elevators, Hohmann bone levers, or Bennett bone levers. A mallet is used to tap a femoral locating device into place after guide pins have been inserted into the femur with a power drill. Note: saws and reamers are other power surgical instruments used in TKA procedures to increase speed and accuracy when placing instruments and resectioning bones. Additional tissue and bone can be removed with rongeurs, curettes, osteomes, or scissors. A distal femoral cutting block is then assembled onto the locating device to help the surgeon make accurate cuts into the patella with an oscillating saw. Additional cuts can be made with anterior and posterior cutting blocks.
The tibia is properly located with a tibial alignment device, and a stylus is used to determine the exact level of resection. An oscillating saw is used to begin the resection which may be completed with an osteotome. Calipers and patellar cutting guides are used to accurately resurface the patella.
After the site is prepared, tibial and femoral trials are used before implanting the components to ensure adequate resection and to confirm that the implants are properly sized. The tibial tray is assembled to the tibial impactor and inserted into the prepared proximal end of the tibia using a mallet. The femoral component is inserted into the prepared distal end of the femur with a femoral impactor and mallet. If it will be cemented, the patella component is held in place by a patella clamp. The final step before closure is to insert the tibial insert. The new joint comprised of the femoral, tibial, and patellar components functions the same as cartilage in a healthy knee to prevent the bones from rubbing together at the joint.
Instruments used for TKA procedures present significant processing challenges for Central Service personnel, and it is critical that they always follow the manufacturers’ instructions when processing them. Many instruments require manual cleaning because bone, tissue and, in some cases, cement can become so embedded in the instruments they must be cleaned with brushes before automatic washing. Drill bits and guides, cutting blocks, and the tibial keel punch and drill are among the instruments that may retain bone and tissue. Some instruments have knurled (crosshatch-designed) handles to help surgeons grip them. However, this feature retains bone, blood, and cement and presents a cleaning challenge.
Central Service staff must also be aware of the detergents used in mechanical washers because they may not be compatible with the metals used to manufacture the TKA instruments and sterilization containers. Central Service technicians should consult the manufacturers’ instructions to learn about detergents that are compatible with the instruments and instrument trays. Also, many TKA instrument trays are designed with multiple layers. Central Service technicians must ensure that tray lids are removed, that instruments are disassembled, and that layers are separated to provide full contact between the spray action of the washer and instruments during cleaning.
TKA instrumentation also poses special inspection challenges. Since instruments are placed directly upon bone and may be exposed to cement, meticulous inspection of all surfaces of each instrument for residual bioburden is imperative. All trials must also be carefully inspected because surgeons may try several sizes to determine that which is best. Femoral and tibial trials, femoral impactors, and large drill bit ends are examples of instruments that are difficult to visually inspect. Central Service employees should use a lighted magnifying glass to view these items, and they may request that a co-worker provide a “double-check” for the most challenging instruments. All instruments with cutting edges must be checked to ensure sharpness. Curettes and osteotomes are tested with a plastic dowel rod, rongeurs are tested with an index card, and scissors should be tested with the appropriate testing material.
A successful system for reprocessing TKA instruments includes written departmental procedures that address several important issues:
TKA instrumentation provides special sterilization challenges because of the size, weight, and number of required trays, and the multiple layers of instruments within the trays. Many vendors require extended sterilization cycle times for TKA instruments. Since there are no standardized instructions, it is necessary to obtain detailed and specific processing information from each vendor providing loaner instrumentation.
Careful inspection, cleaning, and sterilization of TKA instrumentation according to the manufacturers’ requirements and written Central Service Department procedures can help prevent surgery delays, and they are essential elements to a quality patient outcome.
Primary Cruciate-Retaining & Cruciate-Substituting Procedures. DePuy Orthopedics. 2000.
Inspecting Surgical Instruments: An Illustrated Guide. Spectrum Surgical Instruments. 2006.
Instrumentation Resource Course: Identification, Handling and Processing of Surgical Instruments. International Association of Healthcare Central Service Materiel Management. 2006.
Knee Joint Replacement. MedlinePlus. 2005.
M. Swank. Orthopedic Personnel Roles in the OR for Computer-Assisted Total Knee Arthroplasty. AORN Journal. 2005.
Central Service Technical Manual. Seventh Edition. International Association of Healthcare Central Service Materiel Management. 2007.
Special thanks to Tom Andresen. DePuy Orthopedics