Home › Knee Osteoarthritis › NCT06617871

Mechanical Alignment vs Kalipered Kinematic Alignment Total Knee Arthroplasty

A Prospective, Randomized, Single-blinded Clinical Trial Comparing Mechanical Alignment vs Kalipered Kinematic Alignment Total Knee Arthroplasty Using Medacta Spherika

Who can join

Ages 21 to 79 · All sexes

Inclusion Criteria:

* Patient undergoing primary TKA with a medially-stabilized SpheriKA knee system
* Able to read and understand consent form and PRO instruments and willing to return for follow up visits

Exclusion Criteria:

* Varus or Valgus malalignment \>15 degrees to mechanical axis
* Flexion contracture \>15 degrees or flexion \<90 degrees
* BMI \>40
* Revision TKA or other prior knee surgery other than arthroscopy or arthroscopic-assisted ligament reconstruction
* Diagnosis or history of any of the following

  * inflammatory arthritis
  * infection in study knee
  * chronic pain
  * chronic opioid use
  * metabolic musculoskeletal disorder other than osteopenia/osteoporosis
* Patients receiving workers' compensation for study condition
* Patients who cannot complete questionnaires in English
* Patients with comorbidities preventing surgery
* Patients who are not able to provide informed consent

About the study

Knee replacement surgery can be performed in one of two ways. Traditionally the goal was for the new joint to be in a neutral position with respect to the femur (thigh bone). This is called Mechanical Alignment (MA). The neutral position is different than the human knee's natural position, so MA often requires the surgeon to make additional cuts to the ligaments and other soft tissue around the knee. More recently surgeons have started to place the new joint in a position that more closely replicates the natural alignment of the human knee. This is called Kinemetic Alignment (KA). KA can be done without additional soft tissue dissection but the procedure requires a higher level of precision that can be difficult to achieve in every case.

Some studies have found no difference in outcomes between MA and KA, whereas others have found KA to be superior. But these were small studies or studies that did not consider patient-rated outcomes.

What is being tested

• Mechanical Alignment (MA) (procedure)
• Kinematic Alignment (KA) Interventions: (procedure)

Sponsor: Northwestern University · Participants: 95 · Started: Aug 1, 2024

Contact the study team

• Melissa Shauver, MPH · Phone: 312-472-6024
• Megan VanDyke, BSN · Phone: 312-472-3445

Official record on ClinicalTrials.gov — NCT06617871

Locations in the U.S.

Conditions

• Knee Osteoarthritis

From ClinicalTrials.gov, data retrieved Sep 30, 2026. Each study sets its own eligibility; the study team decides who can join.