Authors' objectives: Around 10,000 symptomatic knee articular cartilage injuries requiring repair occur annually in the United Kingdom, mostly in people under 35 years of age. Microfracture surgery aims to restore cartilage. Adding microstructural scaffolds made of collagen may further improve outcomes. To evaluate the clinical and cost-effectiveness of microstructural scaffold in patients undergoing microfracture for a symptomatic chondral or osteochondral defect of the knee.

Authors' results and conclusions: Twenty-two patients were screened across 8 sites, 20 of whom were eligible on screening. Of the 20 patients considered initially eligible, 2 patients were not interested and 1 opted for chondroplasty; the remaining 17 all consented to participate. Between November 2021 and October 2022, 10 participants were randomised, 5 to microfracture and 5 to microfracture with scaffold. Three patients failed the final in-surgery eligibility check (lesions had healed), one decided not to have surgery and three were still waiting when the study was closed. The median age was 38 years, and four participants were female. Most participants (seven) had damage to the lateral femoral condyle, and six had a medial and/or lateral meniscal tear. All participants received the allocated treatment and are included in the reported results. When a scaffold was used, the surgery took on average 10 minutes longer. There were three serious adverse events, knee pain and swelling in one participant, and a suspected anaphylactic reaction in another. The SISMIC randomised controlled trial was severely impacted by the COVID-19 pandemic, the limited resources available at sites and the reduced elective orthopaedic surgical activity.

Authors' methods: Multicentre, parallel two-group, superiority randomised controlled trial with blinding of participants, research staff and clinical care teams not involved in the surgery. National Health Service hospitals offering arthroscopic chondral surgery. Adults aged 18 years or older with symptomatic chondral or osteochondral defects of the knee on the medial or lateral femoral condyles, trochlea or patella and a chondral or osteochondral lesion measuring no more than 4 cm2. Exclusions were: unstable ligamentous injuries or meniscal tears that would not be treated; a knee with defects on the tibial chondral surface,

Project Status: Completed

URL for project: https://www.journalslibrary.nihr.ac.uk/programmes/hta/NIHR136057

Year Published: 2025

URL for published report: https://www.journalslibrary.nihr.ac.uk/hta/published-articles/BRTS2415

URL for additional information: English

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: England, United Kingdom

DOI: 10.3310/BRTS2415

Organisation Name: NIHR Health Technology Assessment programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk