Total Knee Replacement

What Is Total Knee Replacement Surgery?

Knee replacement surgery, also called arthroplasty, is a procedure first performed in 1968 in the US in which a knee damaged by arthritis is replaced with an artificial joint called a prosthesis. The total knee replacement procedure resurfaces the three compartments of the knee with metal and plastic implants, like a crown resurfaces a damaged tooth. These compartments include the inside (medial), outside (lateral) and front (patellofemoral) parts of the knee. Each year more than 700,000 Americans undergo the procedure, and with all the improvements that have been made to the technique and instrumentation, it is one of the safest and most successful types of surgery.

At Adventist Health Lodi Memorial, Dr. Stephen Howell utilizes the kinematic alignment approach to knee replacement, completing more than 500 total knee replacement procedures annually.

What Is the Kinematic Aligned Total Knee Replacement Surgery?

Much like people themselves, no two knees are exactly alike. So, when a knee replacement is needed, the position and fit of implants should be as precise and individual as it can be. Dr. Howell’s preferred surgical method for TKR is “kinematic alignment,” a 3D technique he developed in 2005 to improve placement of the orthopedic implants that form the new knee. Dr. Howell patented this approach and he has performed on nearly 4,000 patients.

The kinematic alignment approach naturally aligns your knee by custom positioning the implants to the native joint line of your knee, just like it was before arthritis developed. This method, which is customized to each patient, speeds recovery and provides better satisfaction, pain relief, function, and flexion than traditional or mechanically aligned TKR. In fact, implant survival at three and six years are also equivalent or better than knee replacements using traditional mechanical alignment.

Unlike the customized placement used in the kinematic alignment approach, mechanical alignment places the implants in an “average” position for all patients, which changes the natural alignment of the limb and knee, causing uncorrectable knee instabilities. The orthopedic literature has shown that 20-25% of patients with mechanically aligned TKR continue to complain of pain, stiffness, and instability, despite the surgical intervention. These undesirable consequences are lessened by customizing the position of the implants with kinematic alignment.

Outcomes Speak for Themselves

Savvy patients will research before committing to knee surgery based on operator outcomes. Dr. Howell has been recognized within the top 3% of surgeons in California for outcomes, as research in the US, China, and Korea has shown that his kinematic alignment technique has better pain relief, function, bending of the knee, and a more normal feeling knee than the traditional technique called mechanical alignment*.

(*sources: 1. Courtney PM. Early Outcomes of Kinematic Alignment in Primary Total Knee Arthroplasty: A Meta-Analysis of the Literature. J Arthroplasty. 2017. 2. Ji HM. Kinematically aligned TKA can align knee joint line to horizontal. Knee Surg Sports Traumatol Arthrosc. 2016;24: 2436-41.3. Lee YS. Kinematic alignment is a possible alternative to mechanical alignment in total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. 2017: 1-13. 4. Matsumoto T. Radiological and clinical comparison of kinematically versus mechanically aligned totalknee arthroplasty. Bone & Joint Journal. 2017;99-B: 640-46.5. Niki Y. Mechanically aligned total knee arthroplasty carries a risk of bony gap changes and flexion-extension axis displacement. Knee Surg Sports Traumatol Arthrosc. 2017: 1-7.)


Some of Dr. Howell’s statistics include:

Dr. Howell (Kinematic Alignment TKR) National Standard (Mechanical Alighment TKR)
Average Length of Stay (LOS) 1.3 Days 3.1 Days
30-Day Readmission Rate 1.5% 2.5%
Major Complications 1% 2.7%

These key performance measures for surgeon performance are substantially better than national standards for the traditional technique called mechanical alignment.*

(*source: Barad SJ, Howell SM, Tom J. Is a shortened length of stay and increased rate of discharge to home associated with a low readmission rate and cost-effectiveness after primary total knee arthroplasty? Arthroplasty Today. 2015.)

Choosing a Medical Leader

Adventist Health Lodi Memorial is proud to partner with Dr. Stephen Howell to provide our patients with an outstanding surgeon, and we are confident your experience in his care will result in a high level of satisfaction.

Watch Dr. Howell perform a Kinematically Aligned Total Knee Replacement Procedure