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Total Knee AnthroplastyNCT07348835

Using a Smart Implantable Device to Compare Early Recovery in Two Different Knee Arthroplasty Approaches

A study testing Total Knee Arthroplasty Medial Parapatellar Approach and Total Knee Arthroplasty Subvastus Approach in people with Total Knee Anthroplasty, run by Total Joint Specialists at 1 site in United States.

Enrolling by invitation

Enrolling by invitation. The study team selects and invites participants, usually from an existing group of patients.

Sites and contacts
Official record
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Trial summary

This is a single-institution, prospective, randomized study comparing the medial parapatellar and subvastus approaches in primary total knee arthroplasty using continuous, implant-based gait monitoring. Read more about this study

Who is it for?
Ages 18 years and older
Conditions the study is for
Total Knee Anthroplasty
What is being tested?
Total Knee Arthroplasty Medial Parapatellar Approach and Total Knee Arthroplasty Subvastus Approach
Type of treatment
Surgery or procedure
Could I receive a placebo?
No, everyone receives an active treatment
How many people
110 participants
Where
1 siteUnited States
Study dates
11 Feb 2026to Jan 2027
Phase
Interventional
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • All patients older than 18 years of age who plan to undergo medial congruent polyethylene bearing primary TKA with a PIQ
  • Eligible for both approaches
  • Have an iPhone and willing to "wear" it for two weeks preoperatively to get an estimated average stepcount
  • Provide informed consent
  • Willing to complete follow ups

Who cannot join

  • Patients with TKA revisions
  • Patients with insufficient pre-operative range of motion in the operative knee (flexion contracture of > 20 degrees or < 90° of knee flexion)
  • Patients with Contralateral TKA within study time frame
  • Patients with TKA other than medial congruent polyethylene bearing
  • Patients with bilateral surgery
  • Patients without a valid and active email address
Show all 9Show fewer
  • Patients not willing or able to participate in study and follow-ups
  • Patients who use assisted devices to ambulate
  • Rheumatoid arthritis

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

United States1 site
  • Total Joint Surgery Center Atlanta

    Sandy Springs, Georgia, 30328

Other trials in United States

About this study

Official title: Continuous Monitoring Using a Smart Implantable Device (Persona IQ®) to Compare Medial Parapatellar vs. Subvastus Approaches in Early Post-Operative Total Knee Arthroplasty Recovery

This is a single-institution, prospective, randomized study comparing the medial parapatellar and subvastus approaches in primary total knee arthroplasty using continuous, implant-based gait monitoring. Patients receiving a Zimmer Persona IQ smart implant will be followed preoperatively and through the first 30 days post-operatively, with extended follow-up to 6 months. Preoperative activity is captured using iPhone Health step-count data, while post-operative recovery is assessed using continuous tibial implant data, including step count, range of motion, cadence, walking speed, stride length, and distance. These objective metrics are correlated with PROMs. The primary outcome is daily step count. Secondary outcomes include early functional milestones, pain, and patient-reported functional scores. This study is designed to characterize early recovery trajectories and determine whether meaningful differences exist between surgical approaches.

Being tested
Total Knee Arthroplasty Medial Parapatellar Approach, Total Knee Arthroplasty Subvastus Approach
Keywords
Total Knee Arthroplasty, Medial Parapatellar Approach, Subvastus Approach

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Total Knee Arthroplasty Medial Parapatellar ApproachProcedure or surgery

    Incision splitting quad

  • Total Knee Arthroplasty Subvastus ApproachProcedure or surgery

    quad-sparing approach

Study groups in NCT07348835
Study groupRoleWhat they receive
Medial Parapatellar ApproachActive comparatorPrimary total knee arthroplasty performed using the medial parapatellar surgical approach
Receives: Procedure: Total Knee Arthroplasty Medial Parapatellar Approach
Subvastus ApproachActive comparatorPrimary total knee arthroplasty performed using the subvastus surgical approach
Receives: Procedure: Total Knee Arthroplasty Subvastus Approach

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Step Count (steps/day)

    Continuously recorded from PIQ device after it is implanted during surgery

    Measured: Through study completion, minimum 6 months

  2. Step Count (steps/day)

    Recorded from patients iPhone Health App for 2 weeks preoperatively

    Measured: Baseline

Secondary outcomes (21)
  1. Stride Length (m)

    Continuously recorded from PIQ device after it is implanted during surgery

    Measured: Through study completion, minimum 6 months

  2. Distance Travelled (km)

    Continuously recorded from PIQ device after it is implanted during surgery

    Measured: Through study completion, minimum 6 months

  3. Functional Range of Motion (degrees)

    Continuously recorded from PIQ device after it is implanted during surgery

    Measured: Through study completion, minimum 6 months

  4. Tibial Range of Motion (degrees)

    Continuously recorded from PIQ device after it is implanted during surgery

    Measured: Through study completion, minimum 6 months

  5. Cadence (steps/minute)

    Continuously recorded from PIQ device after it is implanted during surgery

    Measured: Through study completion, minimum 6 months

  6. Walking Speed (m/s)

    Continuously recorded from PIQ device after it is implanted during surgery

    Measured: Through study completion, minimum 6 months

  7. Goniometric Functional Range of Motion

    Measured in degrees using a goniometer

    Measured: Preoperatively and at 6 weeks

  8. Surgical Side

    Left or Right

    Measured: Preoperatively

  9. Age

    In years, from EMR

    Measured: Preoperatively

  10. Sex

    Male or Female, from EMR

    Measured: Preoperatively

  11. Weight

    In kg, from EMR

    Measured: Preoperatively

  12. Height

    In cm, from EMR

    Measured: Preoperatively

  13. Body Mass Index (BMI)

    in kg/m2, from EMR

    Measured: Preoperatively

  14. Comorbidities

    Collected and listed from EMR

    Measured: Preoperatively

  15. Charlson Comorbidity Index (CCI)

    Calculated from formula using comorbidities collected from EMR

    Measured: Preoperatively

  16. Time to Achieving Key Milestones in Daily Activities

    Survey score collected (less time = better), Survey via Force Therapeutics

    Measured: 6 weeks postoperatively

  17. Veterans Rand 12-Item (VR-12) Health Survey

    Mental and Physical component survey scores collected (0-100); Survey via Force Therapeutics

    Measured: Preoperatively, 6 weeks postoperatively, 6 months postoperatively

  18. Procedure Satisfaction

    Survey score collected (0-5; 5 best), Survey via Force Therapeutics

    Measured: 6 weeks postoperatively

  19. Numeric Pain Rating Scale (NPRS)

    Survey score collected (0-10; 0 best), Survey via Force Therapeutics

    Measured: Preoperatively, 6 weeks postoperatively

  20. Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR.)

    Survey score collected (0-100; 100 best), Survey via Force Therapeutics

    Measured: Preoperatively, 6 weeks postoperatively, 6 months postoperatively

  21. Forgotten Joint Score (FJS)

    Survey score collected (0-100; 100 best), Survey via Force Therapeutics

    Measured: Preoperatively, 6 weeks postoperatively, 6 months postoperatively

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted16 Jan 2026
  2. Study start11 Feb 2026
  3. Primary completionJan 2027 (estimated)
  4. Study completionJan 2027 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Model description
This is a prospective, randomized, parallel-group study. Eligible patients undergoing primary total knee arthroplasty are randomized in a 1:1 ratio to either the medial parapatellar or subvastus surgical approach and followed concurrently. Outcomes are assessed longitudinally.
Masking
Single blind
Who is masked
Participant
Enrolment
110 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07348835
Sponsor's protocol ID
NSH1432
Status last verified
Jan 2026
First submitted
15 Dec 2025
Last updated
9 Oct 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No: Individual participant data will only be used as necessary by the authorized research team and always secured, it will not be shared

Publications

  • Matsueda M, Gustilo RB. Subvastus and medial parapatellar approaches in total knee arthroplasty. Clin Orthop Relat Res. 2000 Feb;(371):161-8. doi: 10.1097/00003086-200002000-00020.

    PubMed 10693563
  • Kazarian GS, Siow MY, Chen AF, Deirmengian CA. Comparison of Quadriceps-Sparing and Medial Parapatellar Approaches in Total Knee Arthroplasty: A Meta-Analysis of Randomized Controlled Trials. J Arthroplasty. 2018 Jan;33(1):277-283. doi: 10.1016/j.arth.2017.08.025. Epub 2017 Aug 30.

    PubMed 28947369
  • Cila E, Guzel V, Ozalay M, Tan J, Simsek SA, Kanatli U, Ozturk A. Subvastus versus medial parapatellar approach in total knee arthroplasty. Arch Orthop Trauma Surg. 2002 Mar;122(2):65-8. doi: 10.1007/s004020100319.

    PubMed 11880904
  • Tomek IM, Kantor SR, Cori LA, Scoville JM, Grove MR, Morgan TS, Swarup I, Moschetti WE, Spratt KF. Early Patient Outcomes After Primary Total Knee Arthroplasty with Quadriceps-Sparing Subvastus and Medial Parapatellar Techniques: A Randomized, Double-Blind Clinical Trial. J Bone Joint Surg Am. 2014 Jun 4;96(11):907-915. doi: 10.2106/JBJS.L.01578. Epub 2014 Jun 4.

    PubMed 24897738
  • Alcelik I, Sukeik M, Pollock R, Misra A, Naguib A, Haddad FS. Comparing the mid-vastus and medial parapatellar approaches in total knee arthroplasty: a meta-analysis of short term outcomes. Knee. 2012 Aug;19(4):229-36. doi: 10.1016/j.knee.2011.07.010. Epub 2011 Aug 20.

    PubMed 21862334
  • Khan MNH, Abbas K, Faraz A, Ilyas MW, Shafique H, Jamshed MH, Hashmi P. Total knee replacement: A comparison of the subvastus and medial parapatellar approaches. Ann Med Surg (Lond). 2021 Aug 8;68:102670. doi: 10.1016/j.amsu.2021.102670. eCollection 2021 Aug.

    PubMed 34408867
  • van Hemert WL, Senden R, Grimm B, van der Linde MJ, Lataster A, Heyligers IC. Early functional outcome after subvastus or parapatellar approach in knee arthroplasty is comparable. Knee Surg Sports Traumatol Arthrosc. 2011 Jun;19(6):943-51. doi: 10.1007/s00167-010-1292-0. Epub 2010 Oct 17.

    PubMed 20953864
  • Berstock JR, Murray JR, Whitehouse MR, Blom AW, Beswick AD. Medial subvastus versus the medial parapatellar approach for total knee replacement: A systematic review and meta-analysis of randomized controlled trials. EFORT Open Rev. 2018 Mar 26;3(3):78-84. doi: 10.1302/2058-5241.3.170030. eCollection 2018 Mar.

    PubMed 29657848

Questions about this trial

What is this clinical trial studying?

A study testing Total Knee Arthroplasty Medial Parapatellar Approach and Total Knee Arthroplasty Subvastus Approach in people with Total Knee Anthroplasty, run by Total Joint Specialists at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: enrolling by invitation, as of the sponsor's last update on 9 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Step Count (steps/day) (time frame: Through study completion, minimum 6 months). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT07348835, which also lists 8 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Oct 2026.

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