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Subchondroplasty® Knee RCT

A Randomized Controlled Trial of the Subchondroplasty® Procedure With Arthroscopy Versus Arthroscopy Alone for Treatment of Bone Marrow Lesions in the Knee

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03112200
Acronym
PRESERVE Knee
Enrollment
131
Registered
2017-04-13
Start date
2017-03-29
Completion date
2023-08-23
Last updated
2026-05-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Bone Marrow Edema, Knee Osteoarthritis, Knee Pain Chronic, Osteoarthritis, Osteoarthritis, Knee

Keywords

Subchondroplasty, Arthroscopy, Bone Substitute Material, Subchondral Bone Defect, AccuFill, Bone Marrow Lesion, Knee Replacement, Knee Replacement Alternative

Brief summary

This is a multi-center, prospective, single-blinded, two-arm study, randomized to include approximately 134 subjects treated with Subchondroplasty (SCP) + Arthroscopy and 67 subjects with arthroscopy alone. The primary objective of this study is to demonstrate superiority of Subchondroplasty with arthroscopy compared to arthroscopy alone for treatment of Bone Marrow Lesions (BMLs) in the knee.

Detailed description

This is a multicenter, prospective, single-blinded, two-arm, randomized study. Enrolled subjects will have a single Bone Marrow Lesion of the tibia, single BML of the femur, or adjoining Bone Marrow Lesions of tibia and femur. Subjects will also be surgical candidates for knee arthroscopy due to mechanical symptoms, meniscus tear, loose body and/or synovitis. A stratified blocked randomization will be used to assign subjects to either Subchondroplasty with arthroscopy or to arthroscopy alone in a 2:1 ratio. Individual sets of blocks will be determined within study site and lesion polarity status (unipolar vs. bipolar). Subjects will be enrolled within 60 days prior to surgery and take part in follow-up visits for two years following surgery. A preoperative visit will occur at the time of enrollment. Follow-up visits were to initially occur at the study site at 6 weeks, 3 months, 6 months, 12 months, and 24 months post-surgery. Telephone follow-up interviews to be be performed at 9 and 18 months post-surgery. Target enrollment was 201 subjects, to include 134 subjects in the treatment group (Subchondroplasty + Arthroscopy) and 67 subjects in the control group (Arthroscopy alone). As of October 2020, follow-up has been amended to be completed remotely, where all visits can be performed electronically and/or via telephone. Subjects will complete the study at the 24 month follow-up visit. For the purposes of this protocol, a revision will be defined as any partial or total joint arthroplasty or any bone fixation, bone grafting or bone substitute procedure in the same compartment in the study knee.

Interventions

PROCEDURESubchondroplasty with Arthroscopy

The Subchondroplasty® (SCP®) Procedure targets and fills bone defects with AccuFill® Bone Substitute Material utilizing an arthroscopic / percutaneous approach. Using intraoperative fluoroscopy, the bone defect is localized relative to MRI findings The appropriate AccuPort® Delivery Cannula is drilled to the bone defect. AccuFill® Bone Substitute Material is then injected into the subchondral bone defect. The calcium phosphate (CaP) fills the edematous void and hardens within the Bone Marrow Lesion. The CaP is resorbed over time and replaced with new bone during the healing process.

PROCEDUREArthroscopy Alone

An endoscopic examination, therapy and surgery of the knee joint.

Sponsors

Zimmer Biomet
Lead SponsorINDUSTRY
MedNet Solutions
CollaboratorUNKNOWN
Medical Metrics Diagnostics, Inc
CollaboratorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Masking description

The surgeon will be blinded to the treatment group until the time of surgery to avoid potential selection bias during the screening process. The subject will be blinded to the treatment group. The research coordinator will consult the central randomization list to determine which group the subject is in. Subjects may be randomized prior to surgery to allow for OR set-up. However, randomization should be performed as close to the time of surgery as possible to reduce the risk of randomization failures due to cancelled procedures.

Intervention model description

A stratified blocked randomization will be used to assign subjects to either Subchondroplasty with arthroscopy or to arthroscopy alone in a 2:1 ratio. Individual sets of blocks will be determined within study site and lesion polarity status (unipolar vs. bipolar).

Eligibility

Sex/Gender
ALL
Age
30 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

* Candidates must meet ALL of the following: 1. Voluntary signature of the Institutional Review Board/Research Ethics Board approved Informed Consent, 2. Male or female subjects between the ages of 30 to 75 years, 3. Body Mass Index ≤ 40 (BMI=kg/m2), 4. Has experienced pain in study knee for at least 3 months, 5. Kellgren-Lawrence grade 1-3 Osteoarthritis, as reviewed on preoperative XR imaging, in the study knee, 6. BML is confirmed on T2 weighted or Proton Density MR Imaging by presence of white signal, 7. Single BML of tibia, single BML of femur, or adjoining BML's of tibia \& femur, in the same compartment, extending to the articular surface of the joint, 8. Surgical candidate for knee arthroscopy due to mechanical symptoms, meniscus tear, loose body and/or synovitis, 9. Must record a response, at the preoperative study visit, of moderate to extreme pain for any one of the KOOS Pain Scale questions, P2 through P9, 10. Index knee alignment is defined radiographically as one of the following: Neutral, ≤ 6° mechanical varus, or ≤ 6° mechanical valgus, 11. Ligaments in the study knee are stable, 12. The contralateral (non-study) knee is stable and functional, 13. Is refractory to conservative non-surgical management 1. having failed 2 or more of the following: hyaluronic acid injection, corticosteroid injection, NSAIDs, physical therapy, bracing, activity modification, or minimal surgical intervention (e.g., arthroscopy, debridement/chondroplasty, and/or loose body removal) 2. and is ≥ 3 months from the start of treatment, 14. Must be physically and mentally willing and able, in the Investigator's opinion at the time of enrollment, to be compliant with the protocol - including all follow-up visits, survey completion, weight-bearing restrictions, and post-operative rehabilitation.

Exclusion criteria

* Candidates will be excluded if they meet ANY of the following: 1. BML caused by acute trauma less than 3 months prior to enrollment, 2. Clinical and/or radiographic disease diagnosis of the index knee that includes any of the following: 1. Kellgren-Lawrence Grade 4 Osteoarthritis with complete loss of joint space (bone-on-bone) or subchondral bone collapse, 2. Rheumatoid arthritis, or history of septic or reactive arthritis, 3. Gout or a history of gout or pseudogout in the affected knee, 4. Has more than two clinically relevant BMLs in the index knee, 5. Osteochondritis dissecans of the knee with significant bone loss, 6. Collapse of subchondral bone, 7. Clinically relevant BML located at ACL/PCL insertion, 8. MRI evidence of frank ligament instability, 3. Passive knee flexion \< 110° or flexion contracture \>30°, 4. History of systemic diseases which could contribute to secondary arthropathies (e.g., sickle cell disease, hemochromatosis, or autoimmune disease), 5. Has a neuromuscular, neurosensory, or musculoskeletal deficiency that limits the ability to perform objective functional assessment of either knee, 6. If diabetic, blood glucose over 200 mg/dL at time of enrollment, 7. Current daily tobacco or high nicotine product user or \< 3 months from nicotine cessation, 8. Presents a high surgical risk due to unstable cardiac and/or pulmonary disease, 9. Has HIV or other immunodeficient state including subjects on immunosuppressant therapies, or has significant illness (metastasis of any type) that decreases the probability of survival to the 2 year endpoint, 10. Is at substantial risk for the need of organ transplantation, such as renal insufficiency, 11. Is pregnant or breast-feeding at the time of surgery, 12. Has a history of any invasive malignancy (except non-melanoma skin cancer), unless treated with curative intent and with no clinical signs or symptoms of the malignancy for 5 years, 13. Has primary bone tumor in the knee area, 14. Anticipates having a lower extremity surgery other than the investigational surgery during the course of the study, 15. Is participating concurrently in another clinical trial, or has participated in a clinical trial within 30 days of surgery, 16. Is receiving prescription pain medication other than NSAIDs or acetaminophen for conditions unrelated to the index knee condition, chronic use of anticoagulants, or taking corticosteroids, 17. Active joint infection or history of chronic joint infection at the surgical site, 18. Prior total meniscectomy of index knee, 19. Has primarily patellofemoral symptoms, 20. Is indicated for concomitant procedures (i.e., microfracture, subchondral drilling, cartilage allograft, ligament or tendon repair, distal realignment/osteotomy, root repair) in the index knee, with the exception of incidental loose body removal, debridement, synovectomy, osteophyte removal in locations other than adjacent to BMLs, and/or partial meniscectomy, 21. Has contraindications for Magnetic Resonance Imaging (MRI), 22. Is receiving worker's compensation or is currently involved in litigation relating to the index knee, 23. Has a history of substance abuse.

Design outcomes

Primary

MeasureTime frameDescription
Composite Clinical SuccessSuperiority will be statistically tested at month 12 at p<0.01The primary objective of this study is to determine whether Subchondroplasty with arthroscopy is superior to arthroscopy alone for treatment of bone marrow lesions in the knee. Superiority will be evaluated in terms of Composite Clinical Success (CCS) requiring freedom from subsequent secondary surgical intervention (SSSI) and among those free from SSSI, a clinically meaningful reduction in self-reported pain based on a validated measure of subject-reported pain (improvement in KOOS (Knee Injury and Osteoarthritis Outcome Score) pain of at least 10 points at 12 months). For the purpose of this study, SSSI will include any partial or total joint arthroplasty or any bone grafting or bone substitute procedure in the study knee.

Secondary

MeasureTime frameDescription
Change From Baseline KOOS Subscale Scores at 12 Months12 months post-surgeryComparison of mean change in KOOS subscale scores (Pain, Activities of Daily Living), Symptoms, Sports and Recreation, Quality of Life). Each subscale is scored from 0 to 100 on a worst to best scale.
Change From Baseline Numeric Pain Score at 12 Months12 months post-surgeryComparison of mean Numeric Pain Score (NPS). The NPS is scored from 0 to 10 where 0 indicates no pain; 5 indicates moderate pain; and 10 indicates the worst pain.
Change From Baseline EQ-5D Index Score at 12 Months12 months post-surgeryComparison of mean EQ-5D Index score
Global Satisfaction Score at 6-Weeks6-weeks post-surgeryPatient satisfaction with knee procedure rated on a 0-10 scale, where 0 = totally dissatisfied and 10 = extremely satisfied.
Change From Baseline KOOS Subscale Scores at 24 Months24 months post-surgeryComparison of mean change in KOOS subscale scores (Pain, Activities of Daily Living), Symptoms, Sports and Recreation, Quality of Life). Each subscale is scored from 0 to 100 on a worst to best scale.
Change From Baseline Numeric Pain Score at 24 Months24 months post-surgeryComparison of mean Numeric Pain Score (NPS). The NPS is scored from 0 to 10 where 0 indicates no pain; 5 indicates moderate pain; and 10 indicates the worst pain.
Change From Baseline EQ-5D Overall Health Score at 12 Months12 months post-surgeryComparison of mean EQ-5D Overall Health score using the EQ Visual Analog Scale (VAS), ranging from 0 (worst imaginable health) to 100 (best imaginable health).
Change From Baseline EQ-5D Overall Health Score at 24 Months24 months post-surgeryComparison of mean EQ-5D Overall Health score using the EQ Visual Analog Scale (VAS), ranging from 0 (worst imaginable health) to 100 (best imaginable health).
Global Satisfaction Score at 3 Months3 Months post-surgeryPatient satisfaction with knee procedure rated on a 0-10 scale, where 0 = totally dissatisfied and 10 = extremely satisfied.
Global Satisfaction Score at 6 Months6 months post-surgeryPatient satisfaction with knee procedure rated on a 0-10 scale, where 0 = totally dissatisfied and 10 = extremely satisfied.
Global Satisfaction Score at 12 Months12 months post-surgeryPatient satisfaction with knee procedure rated on a 0-10 scale, where 0 = totally dissatisfied and 10 = extremely satisfied.
Global Satisfaction Score at 24 Months24 months post-surgeryPatient satisfaction with knee procedure rated on a 0-10 scale, where 0 = totally dissatisfied and 10 = extremely satisfied.

Countries

Canada, United States

Contacts

PRINCIPAL_INVESTIGATORJason Dragoo, MD

University of Colorado, Denver

Baseline characteristics

Characteristic
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
27 Participants
Age, Categorical
Between 18 and 65 years
104 Participants
Age, Continuous57.3 years
STANDARD_DEVIATION 9
EQ-5D Index Score0.1 Index Score
STANDARD_DEVIATION 0.3
EQ-5D Overall Health75.7 Points on a scale (0-100)
STANDARD_DEVIATION 16.8
Imaging Completed at Baseline33 Participants
KOOS Subscale Scores
Activities of Daily Living
50.7 units on a scale
STANDARD_DEVIATION 19.4
KOOS Subscale Scores
Pain
42.9 units on a scale
STANDARD_DEVIATION 15
KOOS Subscale Scores
Quality of Life
19.6 units on a scale
STANDARD_DEVIATION 17
KOOS Subscale Scores
Sports and Recreation
17.6 units on a scale
STANDARD_DEVIATION 20.2
KOOS Subscale Scores
Symptoms
49.7 units on a scale
STANDARD_DEVIATION 18.5
Number of Bone Lesions
1
59 Participants
Number of Bone Lesions
2
42 Participants
Numeric Pain Score5.9 Score (0-10)
STANDARD_DEVIATION 2.2
Race/Ethnicity, Customized
American Indian or Alaska Native
1 Participants
Race/Ethnicity, Customized
Asian
1 Participants
Race/Ethnicity, Customized
Black or African American
4 Participants
Race/Ethnicity, Customized
Decline to Respond
1 Participants
Race/Ethnicity, Customized
Hispanic or Latino
1 Participants
Race/Ethnicity, Customized
Native Hawaiian or Other Pacific Islander
0 Participants
Race/Ethnicity, Customized
White
75 Participants
Region of Enrollment
Canada
3 participants
Region of Enrollment
United States
82 participants
Sex: Female, Male
Female
47 Participants
Sex: Female, Male
Male
41 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 880 / 43
other
Total, other adverse events
30 / 8814 / 43
serious
Total, serious adverse events
13 / 885 / 43

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 15, 2026