Comparing two methods of knee replacement surgery

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

NA · Northwestern University · NCT06617871

This study is testing two different knee replacement surgery techniques to see which one makes patients feel better and have better results after their operation.

Quick facts

PhaseNA
Study typeInterventional
Enrollment95 (estimated)
Ages21 Years to 79 Years
SexAll
SponsorNorthwestern University (other)
Locations1 site (Chicago, Illinois)
Trial IDNCT06617871 on ClinicalTrials.gov

What this trial studies

This clinical trial compares two surgical techniques for total knee arthroplasty: Mechanical Alignment (MA) and Kinematic Alignment (KA). MA positions the new joint in a neutral position, often requiring additional soft tissue adjustments, while KA aims to replicate the natural alignment of the knee without extensive dissection. The study seeks to determine which method leads to better patient satisfaction and outcomes, particularly focusing on patient-rated results. By analyzing the effectiveness of these approaches, the trial aims to address the dissatisfaction experienced by some patients post-surgery.

Who should consider this trial

Good fit: Ideal candidates are patients undergoing primary total knee arthroplasty with a specific knee system and who can understand and complete follow-up assessments.

Not a fit: Patients with significant malalignment, severe obesity, or prior knee surgeries may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved surgical techniques that enhance patient satisfaction and reduce chronic pain after knee replacement.

How similar studies have performed: Previous studies comparing these alignment techniques have shown mixed results, indicating that this area of research is still evolving.

Eligibility criteria

Show full inclusion / exclusion criteria
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

Where this trial is running

Chicago, Illinois

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Knee Osteoarthritis, Knee Arthropathy, randomized trial, knee arthroplasty

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.