NCT07555899

Brief Summary

Osteochondral lesions of the ankle (OsteoChondral Lesions - OCLs) are defects of the subchondral bone and the overlying articular cartilage that commonly affect young and active patients. The main symptoms include chronic ankle pain, recurrent swelling, stiffness, and instability. The ideal treatment for OCLs remains a matter of debate. Various surgical techniques have been proposed, both arthroscopic and open. The choice of treatment depends on several factors, including lesion pathology, patient characteristics, and surgeon preference. In the presence of subchondral cysts or lesions with intact and stable cartilage surfaces, retrograde drilling is among the most commonly used techniques. This is a reparative, extra-articular procedure that reaches the lesion via a retrograde approach, thereby preventing iatrogenic cartilage damage. The surgical technique involves creating multiple channels in the subchondral bone using a Kirschner wire to stimulate the migration of mesenchymal stem cells, promote revascularization of the lesion site, and induce new bone formation. Although retrograde drilling has shown good results over the years, concerns remain regarding the regenerative potential of subchondral bone, particularly in the case of large lesions or cysts. For this reason, various biological adjuncts have been combined with drilling in an attempt to improve treatment efficacy, with inconclusive results. Among the proposed modifications is that of Beck et al., who expanded the talar tunnel to allow for improved debridement, subsequently filling it with bone graft. Another treatment option is subchondroplasty, which has shown promising results; however, few studies are available for the ankle, and significant complications have been reported. Therefore, the management of large subchondral cysts remains controversial. In cases of large OCLs with cartilage damage, regenerative treatments are generally preferred, and several surgical techniques can be performed. However, these approaches are also controversial, as they are typically performed via an anterograde approach and involve extensive debridement of the overlying damaged cartilage, sometimes removing healthy cartilage as well. Significant improvements in AOFAS scores have been reported for all currently used techniques, but none has emerged as the gold standard. Consequently, clinical research is focused on developing new interventions that demonstrate superiority over traditional techniques. In this context, subendocondral regenerative treatment has gained interest. This approach involves the application of a bone marrow-derived scaffold combined with retrograde drilling in patients with subchondral cysts and intact cartilage or large OCLs of the ankle. This innovative surgical technique combines several procedures already validated in the literature, aiming to leverage their advantages and enhance overall efficacy. First, it includes an intra-articular arthroscopic approach to assess cartilage status, remove loose bodies, and treat associated conditions such as synovitis, soft tissue impingement, exostoses, and osteophytes. After confirming the appropriate indication based on arthroscopic findings, a Kirschner wire is inserted retrogradely into the lesion under fluoroscopic guidance. Retrograde drilling is then performed using a dedicated reamer. The novelty of this procedure lies in the placement of a hyaluronic scaffold enriched with bone marrow-derived cells beneath the cartilage, which is therefore not further disrupted. This fully biodegradable scaffold creates a favorable microenvironment for regeneration by supporting the adhesion of bone marrow-derived stem cells and their three-dimensional organization, thereby facilitating restoration of normal tissue anatomy. Large subchondral cysts have shown limited healing potential due to poor vitality of the subchondral bone and a lack of mesenchymal stem cells needed for lesion repair. Therefore, a cartilage scaffold enriched with bone marrow-derived cells may represent an important source of mesenchymal stem cells and promote cellular interaction and mechanical stability during the regenerative process. This scaffold has been approved for the repair of chondral or osteochondral lesions; however, clinical and MRI outcomes following its subchondral placement in the presence of intact cartilage have not yet been described. The aim of this pilot study is to evaluate the clinical and imaging outcomes of this innovative surgical technique for subchondral regenerative treatment, which involves the application of a scaffold enriched with bone marrow-derived cells combined with retrograde drilling in patients with subchondral cysts and intact cartilage or large osteochondral lesions of the talus.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
20

participants targeted

Target at below P25 for not_applicable

Timeline
21mo left

Started Jan 2026

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Progress13%
Jan 2026Feb 2028

Study Start

First participant enrolled

January 30, 2026

Completed
3 months until next milestone

First Submitted

Initial submission to the registry

April 21, 2026

Completed
8 days until next milestone

First Posted

Study publicly available on registry

April 29, 2026

Completed
1.7 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

January 1, 2028

Expected
1 month until next milestone

Study Completion

Last participant's last visit for all outcomes

February 1, 2028

Last Updated

April 29, 2026

Status Verified

April 1, 2026

Enrollment Period

1.9 years

First QC Date

April 21, 2026

Last Update Submit

April 21, 2026

Conditions

Outcome Measures

Primary Outcomes (1)

  • To evaluate clinical and imaging outcomes in patients treated with retrograde drilling and application of bone marrow aspirate on a scaffold for the treatment of subchondral cysts with intact cartilage or large osteochondral lesions of the ankle at the d

    january 2026 - january 2028

Secondary Outcomes (1)

  • To evaluate MRI outcomes at 12 months using the T2 mapping protocol, which allows assessment of the biomechanical properties of the cartilage matrix, including collagen content and water percentage, by subjecting patients to MRI. The images will be indep

    january 2026 - january 2028

Study Arms (1)

Osteochondral lesions treated with a scaffold enriched with bone marrow-derived cells at the subchon

EXPERIMENTAL
Other: Osteochondral lesions treated with a scaffold enriched with bone marrow-derived cells at the subchondral level combined with retrograde drilling.

Interventions

First, the procedure includes an intra-articular arthroscopic approach to assess the condition of the cartilage, remove any loose bodies, and treat associated conditions such as synovitis, soft tissue impingement, exostoses, and osteophytes. After confirming the appropriate indication based on arthroscopic findings, a Kirschner wire is inserted retrogradely into the lesion under fluoroscopic guidance. Retrograde drilling is then performed using a dedicated reamer. The novelty of this procedure lies in the placement of a hyaluronic scaffold enriched with bone marrow-derived cells beneath the cartilage, which is therefore not further disrupted. This fully biodegradable scaffold creates a favorable microenvironment for regeneration by supporting the adhesion of bone marrow stem cells and their three-dimensional organization, thereby facilitating restoration of normal tissue anatomy. Large subchondral cysts have shown limited healing potential due to poor vitality of the subchondral bone a

Osteochondral lesions treated with a scaffold enriched with bone marrow-derived cells at the subchon

Eligibility Criteria

Age18 Years - 55 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may qualify if:

  • Patients with one or more chronic cystic subchondral lesions of the talus (Grade IIA according to the Giannini classification); Patients with one or more chronic subchondral lesions with intact cartilage or large chronic OCLs (Grade IIA according to the Giannini classification); Age ≥ 18 years and ≤ 55 years; Ankle pain with limitation in normal activities of daily living (American Orthopaedic Foot and Ankle Score - AOFAS \< 85, Short Form-36 - SF-36 \< 86); Patients able to provide written informed consent to participate in the study.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Istituto Ortopedico Rizzoli

Bologna, Italy

RECRUITING

Central Study Contacts

Antotnio Mazzotti, MD PhD

CONTACT

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

April 21, 2026

First Posted

April 29, 2026

Study Start

January 30, 2026

Primary Completion (Estimated)

January 1, 2028

Study Completion (Estimated)

February 1, 2028

Last Updated

April 29, 2026

Record last verified: 2026-04

Locations