Medial Compartment OsteoarthritisNCT07220434
TO Plate Fixation vs. External Fixator Comparison (HTO Plate vs. ExFix Study)
A study testing Medial HTO Locking Plate and Self-Adjusting HTO External Fixator in people with Medial Compartment Osteoarthritis and Genu Varum, run by Muhammed Cagatay Engin at 1 site in Turkey (Türkiye).
Trial summary
This study aims to compare the efficacy, accuracy, and functional outcomes of two different surgical stabilization techniques for medial opening wedge high tibial osteotomy (HTO) in patients with varus deformity and medial compartment osteoarthritis. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Medial Compartment Osteoarthritis, Genu Varum, Varus Deformity
- What is being tested?
- Medial HTO Locking Plate and Self-Adjusting HTO External Fixator
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 28 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 15 Nov 2025to 31 Dec 2028
- 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
- Varus malalignment associated with medial compartment degeneration/osteoarthritis.
- Indication for Medial Opening Wedge HTO. Aged 18 years or older. Willing to participate in the study and provide written informed consent.
Who cannot join
- Advanced-stage osteoarthritis (Indication for Total Knee Arthroplasty). Previous open knee surgery on the same extremity. Inability to comply with follow-up appointments. Significant comorbidities (e.g., uncontrolled diabetes, 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.
Turkey (Türkiye)1 site
Ataturk University, Department of Orthopedics and Traumatology
Erzurum, Erzurum, 25240
Muhammed Çağatay ENGİN, Assoc. Prof., +90 532 330 1949, mcagatayengin@hotmail.com
About this study
Official title: Medial Opening Wedge High Tibial Osteotomy: A Comparative Study of Plate Fixation and Self-Adjusting HTO External Fixator Techniques
This study aims to compare the efficacy, accuracy, and functional outcomes of two different surgical stabilization techniques for medial opening wedge high tibial osteotomy (HTO) in patients with varus deformity and medial compartment osteoarthritis. Patients will be prospectively randomized into two groups: Group 1 (Plate Fixation) will receive acute (single-stage) correction and stabilization with a medial HTO locking plate. Group 2 (HTO External Fixator) will receive stabilization using a self-adjusting HTO external fixator, followed by gradual correction (hemicallotasis/distraction) starting 7 days post-operatively. The study will evaluate radiological correction, functional improvement (using the Oxford Knee Score), and complication rates over a 12-month follow-up period.
- Being tested
- Medial HTO Locking Plate, Self-Adjusting HTO External Fixator
- Medical subject headings
- Genu Varum
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Medial HTO Locking PlateDevice
Medial Opening Wedge High Tibial Osteotomy.
Self-Adjusting HTO External FixatorDevice
Medial Opening Wedge High Tibial Osteotomy.
| Study group | Role | What they receive |
|---|---|---|
| Group 1: Plate Fixation | Experimental | The osteotomy will be acutely corrected intraoperatively and stabilized using a Medial High Tibial locking plate. Receives: Device: Medial HTO Locking Plate |
| Group 2: HTO External Fixator | Active comparator | he osteotomy will be stabilized using a Self-Adjusting HTO External Fixator. Gradual distraction (hemicallotasis) will begin 7 days post-operatively at a rate of 1 mm per day to achieve correction. Receives: Device: Self-Adjusting HTO External Fixator |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Radiological Correction (Hip-Knee-Ankle Angle - HKA)
ssessment of the mechanical axis on full-length weight-bearing radiographs (Measured in degrees).
Measured: Baseline (Preoperative), 6 Weeks, 3 Months, 6 Months, and 12 Months Postoperative.
Change in Functional Status (Oxford Knee Score - OKS)
Patient-reported functional score assessing pain and knee function.
Measured: Baseline (Preoperative), 6 Weeks, 3 Months, 6 Months, and 12 Months Postoperative.
Change in Pain Intensity (Visual Analogue Scale - VAS)
Patient-reported pain score from 0 (no pain) to 10 (intolerable pain).
Measured: Baseline (Preoperative), 6 Weeks, 3 Months, 6 Months, and 12 Months Postoperative
Secondary outcomes (5)
Change in Femoro-Tibial Angle (FTA)
Change in the anatomical axis measured in degrees.
Measured: Baseline (Preoperative) and 12 Months Postoperative.
Change in Mechanical Axis Percentage (MA%)
Change in the position of the weight-bearing line on the tibial plateau.
Measured: Baseline (Preoperative) and 12 Months Postoperative.
Change in Posterior Tibial Slope (PTE)
Change in the tibial slope measured in degrees.
Measured: Baseline (Preoperative) and 12 Months Postoperative.
Change in Patellar Height (Insall-Salvati Index)
Change in patellar height measured by the Insall-Salvati ratio.
Measured: Baseline (Preoperative) and 12 Months Postoperative.
Incidence of Complications
Incidence of adverse events including pin tract infection (especially Group 2), superficial or deep infection, non-union/delayed union, lateral cortex fracture, hardware exposure, or knee stiffness.
Measured: Up to 12 months postoperative.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Oct 2025
- Study start15 Nov 2025 (estimated)
- Primary completion31 Dec 2028 (estimated)
- Study completion31 Dec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Medial Compartment OsteoarthritisStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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
- Masking
- None (open label)
- Enrolment
- 28 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Muhammed Cagatay Engin
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Muhammed Cagatay Engin, Ataturk University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07220434
- Sponsor's protocol ID
- HTOexfix1
- Status last verified
- Oct 2025
- First submitted
- 22 Oct 2025
- Last updated
- 23 Oct 2025
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 23 Oct 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Medial Opening Wedge High Tibial Osteotomy: A Comparative Study of Plate Fixation and Self-Adjusting HTO External Fixator Techniques
- ClinicalTrials.gov ID
- NCT07220434
- Acronym / sponsor ID
- HTOexfix1
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 28 participants (estimated)
- Lead sponsor
- Muhammed Cagatay EnginUniversity, hospital or other
- Study start
- 15 Nov 2025 (estimated)
- Primary completion
- 31 Dec 2028 (estimated)
- Study completion
- 31 Dec 2028 (estimated)
- First posted
- 23 Oct 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to compare the efficacy, accuracy, and functional outcomes of two different surgical stabilization techniques for medial opening wedge high tibial osteotomy (HTO) in patients with varus deformity and medial compartment osteoarthritis. Patients will be prospectively randomized into two groups: Group 1 (Plate Fixation) will receive acute (single-stage) correction and stabilization with a medial HTO locking plate. Group 2 (HTO External Fixator) will receive stabilization using a self-adjusting HTO external fixator, followed by gradual correction (hemicallotasis/distraction) starting 7 days post-operatively. The study will evaluate radiological correction, functional improvement (using the Oxford Knee Score), and complication rates over a 12-month follow-up period.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group 1: Plate Fixation | Experimental | Device: Medial HTO Locking PlateThe osteotomy will be acutely corrected intraoperatively and stabilized using a Medial High Tibial locking plate. |
| Group 2: HTO External Fixator | Active comparator | Device: Self-Adjusting HTO External Fixatorhe osteotomy will be stabilized using a Self-Adjusting HTO External Fixator. Gradual distraction (hemicallotasis) will begin 7 days post-operatively at a rate of 1 mm per day to achieve correction. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Varus malalignment associated with medial compartment degeneration/osteoarthritis.
- Indication for Medial Opening Wedge HTO. Aged 18 years or older. Willing to participate in the study and provide written informed consent.
Key exclusion criteria (1 listed)
- Advanced-stage osteoarthritis (Indication for Total Knee Arthroplasty). Previous open knee surgery on the same extremity. Inability to comply with follow-up appointments. Significant comorbidities (e.g., uncontrolled diabetes, rheumatoid arthritis).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Medial HTO Locking PlateMedial Opening Wedge High Tibial Osteotomy. | Device | Group 1: Plate Fixation |
| Self-Adjusting HTO External FixatorMedial Opening Wedge High Tibial Osteotomy. | Device | Group 2: HTO External Fixator |
Primary outcome
Change in Radiological Correction (Hip-Knee-Ankle Angle - HKA)
Time frame: Baseline (Preoperative), 6 Weeks, 3 Months, 6 Months, and 12 Months Postoperative.
ssessment of the mechanical axis on full-length weight-bearing radiographs (Measured in degrees).
Change in Functional Status (Oxford Knee Score - OKS)
Time frame: Baseline (Preoperative), 6 Weeks, 3 Months, 6 Months, and 12 Months Postoperative.
Patient-reported functional score assessing pain and knee function.
Change in Pain Intensity (Visual Analogue Scale - VAS)
Time frame: Baseline (Preoperative), 6 Weeks, 3 Months, 6 Months, and 12 Months Postoperative
Patient-reported pain score from 0 (no pain) to 10 (intolerable pain).
5 secondary outcomes
Change in Femoro-Tibial Angle (FTA)
Time frame: Baseline (Preoperative) and 12 Months Postoperative.
Change in Mechanical Axis Percentage (MA%)
Time frame: Baseline (Preoperative) and 12 Months Postoperative.
Change in Posterior Tibial Slope (PTE)
Time frame: Baseline (Preoperative) and 12 Months Postoperative.
Change in Patellar Height (Insall-Salvati Index)
Time frame: Baseline (Preoperative) and 12 Months Postoperative.
Incidence of Complications
Time frame: Up to 12 months postoperative.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Oct 2025.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Medial HTO Locking Plate and Self-Adjusting HTO External Fixator in people with Medial Compartment Osteoarthritis and Genu Varum, run by Muhammed Cagatay Engin at 1 site in Turkey (Türkiye).
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 2 inclusion and 1 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: opening soon, as of the sponsor's last update on 23 Oct 2025. 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 Turkey (Türkiye). 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?
Contact ali afşar, md (+905374927543, afsarali1708@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Radiological Correction (Hip-Knee-Ankle Angle - HKA) (time frame: Baseline (Preoperative), 6 Weeks, 3 Months, 6 Months, and 12 Months Postoperative.). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 23 Oct 2025.