Accessibility Tools

What is Joint Replacement Surgery?

Joints are formed by the ends of two or more bones connected by tissue called cartilage. Healthy cartilage serves as a protective cushion, allowing smooth and low-friction movement of the joint. If the cartilage becomes damaged by disease or injury, the tissues around the joint become inflamed, causing pain. With time, the cartilage wears away, allowing the rough edges of bone to rub against each other, causing more pain.

When only some of the joint is damaged, a surgeon may be able to repair or replace just the damaged parts. When the entire joint is damaged, a total joint replacement is done. To replace a total hip or knee joint, a surgeon removes the diseased or damaged parts and inserts artificial parts, called prostheses or implants.

For general information about joint replacement please see the following videos

Click the desired topics below to find out more

There are many things to consider when approaching total knee replacement We will discuss a few of them here and include information on Dr. Gilmer’s preferred approaches. Further on will be information about the two techniques used currently in Dr. Gilmer’s practice and the specific implants with information from the manufacturers: 1) The Stryker Triathalon total knee system with the MAKO robotic assistance 2) The Medacta MyKnee custom total knee system. Both systems are based off a CAT scan or CT scan which is a 3 dimensional scan of your knee that allows us to precisely size and match your knee to provide the optimum restoration of function and comfort.

Mechanical Versus Kinematic Alignment

In total knee replacement surgery, there are two primary alignment strategies: kinematic and mechanical. Mechanical alignment aims to align the knee joint with the hip and ankle, creating a straight line. In contrast, kinematic alignment focuses on restoring the natural alignment of the knee, taking into account the unique anatomy and biomechanics of each patient. This approach attempts to mimic the natural movement and alignment of the knee, which can potentially lead to better function and patient satisfaction post-surgery. Some potential advantages of the kinematic alignment approach include a more natural feeling in the knee, less bone and soft tissue damage during surgery, and potentially a quicker recovery time. Dr. Gilmer generally adopts a kinematic approach within boundaries, meaning that any large deformities may only be partially corrected to prevent excessive wear which can occur from malalignment. It is important to remember that malalignment can lead to premature wear in a knee replacement just as it does in the original knee (that led to the arthritis to begin with). The goal is to balance comfort and a natural feel with the best wear rate for the long term.

Outpatient Versus Inpatient Surgery

Total knee arthroplasty, also known as knee replacement surgery, can be performed as an inpatient or outpatient procedure. Inpatient surgery involves a hospital stay, typically for a few days post-surgery. On the other hand, outpatient surgery allows the patient to return home on the same day of the procedure. Outpatient total joint surgery offers several potential benefits. It is often more cost-effective as it eliminates the need for a prolonged hospital stay. Additionally, recovering at home can be more comfortable for many patients and may reduce the risk of hospital-acquired infections. It’s also been found that with the appropriate patient selection and a comprehensive perioperative care plan, outpatient surgery can lead to similar, if not better, outcomes as inpatient surgery. However, the choice between inpatient and outpatient surgery is always made with consideration of safety as the top priority, taking into account your overall health, living situation, and personal preferences. The overwhelming majority of patients will be candidates for an outpatient procedure. For more information on the outpatient centers where surgery is typically performed please see our surgery sites

Partial Versus Total Knee Replacement

Unicompartmental knee arthroplasty, also known as partial knee replacement, is typically indicated for patients who have osteoarthritis confined to a single compartment of the knee. This procedure can be a beneficial choice for individuals with relatively good knee function, intact ligaments, and who are not excessively overweight. The potential advantages of unicompartmental knee arthroplasty, when compared to total knee arthroplasty, include less blood loss, shorter hospital stay, and quicker recovery time, due to the less invasive nature of the surgery. Moreover, it often results in more natural knee movement post-operatively, as it preserves more of the patient’s own anatomy. However, for patients with multi-compartmental knee disease, total knee arthroplasty may be the more appropriate choice. This procedure replaces the entire knee joint and can provide more comprehensive relief from pain and disability. The selection between unicompartmental and total knee arthroplasty is multifactorial and in general most patients opt for total knee arthroplasty. More information about each of these may be found in the EncycloKNEEdia section:

Managing Risk Factors

Managing the three primary risk factors for infection and poor outcomes after total knee replacement — smoking, diabetes, and obesity — is crucial for a successful surgery and recovery. Numerous studies have documented the increased risk of postoperative complications associated with these comorbidities.

Smoking has been linked with a higher risk of surgical site infections due to its negative impact on wound healing and immune function (Sorensen, 2012). Therefore, patients should be encouraged to quit smoking prior to surgery and maintain abstinence during recovery.

Diabetes, particularly when poorly controlled, can also increase the risk of postoperative infection, as elevated blood sugar levels can impair the body’s ability to fight infection (Marchant et al., 2009). Thus, optimal glycemic control should be achieved before surgery and maintained postoperatively.

Obesity has been associated with increased surgical complications, including infection, due to the technical challenges it presents and its association with other comorbidities (Namba et al., 2005). Weight loss, when feasible, should be encouraged before surgery to reduce these risks.

In conclusion, a multidisciplinary approach involving the patient, primary care physician, and surgeon is essential to manage these risk factors and optimize patient outcomes after total knee replacement. In general Dr. Gilmer strongly recommends smoking cessation, weight loss to a BMI under 35, and diabetes management to Hgb A1C less than 7.7 (ideally closer to 7.0)


  1. Sorensen LT. Wound healing and infection in surgery: the clinical impact of smoking and smoking cessation: a systematic review and meta-analysis. Arch Surg. 2012;147(4):373-383.
  2. Marchant MH Jr, Viens NA, Cook C, Vail TP, Bolognesi MP. The impact of glycemic control and diabetes mellitus on perioperative outcomes after total joint arthroplasty. J Bone Joint Surg Am. 2009;91(7):1621-1629.
  3. Namba RS, Paxton L, Fithian DC, Stone ML. Obesity and perioperative morbidity in total hip and total knee arthroplasty patients. J Arthroplasty. 2005;20(7 Suppl 3):46-50.

My Knee


Photography courtesy of Dr. Tyler Williamson – Perfect Circles Photography – for more information or to purchase prints please visit –


Photography courtesy of Dr. Tyler Williamson – Perfect Circles Photography – for more information or to purchase prints please visit –

  • The American Board of Orthopaedic Surgery Logo
  • American Academy of Orthopaedic Surgeons Logo
  • Arthoscopy Association of North America Logo
  • American Orthopaedic Society for Sports Medicine Logo
  • Mammoth Orthopedic Institute Logo
  • Swift Institute Logo