03/03/2025
Hot off the Press 🔥
Can baseline MRI findings identify who responds better to early surgery versus exercise and education in young patients with meniscal tears 🦵?
🦵 Knee arthroscopy for meniscal injuries remains among the most frequently performed orthopedic procedures (https://pmc.ncbi.nlm.nih.gov/articles/PMC6584718/, https://pubmed.ncbi.nlm.nih.gov/21531866/, https://pubmed.ncbi.nlm.nih.gov/37434234/).
👉 Recent randomized controlled trials (RCTs) in young adults with meniscal tears found that early arthroscopic surgery did not provide superior patient-reported outcomes at 12 or 24 months compared to a strategy of exercise and education, with subsequent surgery if needed (https://pubmed.ncbi.nlm.nih.gov/37879858/, https://pubmed.ncbi.nlm.nih.gov/38319181/, https://pubmed.ncbi.nlm.nih.gov/35676079/).
👉 S.https://www.bodyworkmovementtherapies.com/cms/10.1016/j.jbmt.2017.07.010/attachment/31656b55-b97c-4b6a-ac12-7ad51c95a933/mmc1.pdf for details of the exercise program.
👉 However, certain patient subgroups may respond better to one treatment approach over the other (https://pubmed.ncbi.nlm.nih.gov/36878666/). Identifying these subgroups based on clinical characteristics that modify treatment effects (https://pubmed.ncbi.nlm.nih.gov/36244961/) could enhance patient counselling and support more personalized treatment decisions.
📘 A brand-new study by Clausen et al. (2025, https://www.jospt.org/doi/10.2519/jospt.2025.12994), a secondary subgroup analysis of the DREAM trial, investigated whether specific baseline MRI findings could predict which young patients with meniscal tears would benefit more from early surgery compared to exercise and education.
✅ Objectives of the Study
❓ The study focused on three predefined MRI characteristics as potential effect modifiers:
1️⃣ Type of meniscal tear – categorized as simple (radial/longitudinal) or complex (bucket-handle, displaced, or complex tears, s. illustration, https://pubmed.ncbi.nlm.nih.gov/26724644/).
2️⃣ Meniscus affected – whether the tear was located in the medial or lateral meniscus.
3️⃣ Presence of knee effusion/synovitis – present in any knee recess versus no effusion/synovitis
✅ Methods
▶️ The study utilized data from the DREAM trial, a randomized controlled trial (RCT) comparing early meniscal surgery to a structured exercise program with patient education. The study population consisted of 121 patients aged 18–40 years with MRI-confirmed meniscal tears, with 60 in the surgical group and 61 in the exercise group. Patients were followed for 12 months, and outcomes were assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS4).
▶️ A linear mixed model was used to analyse treatment effects, and an adjusted effect difference of ≥10 points on KOOS4 was considered clinically relevant.
🔑 Key Findings
🔑 Knee Effusion/Synovitis as a Potential Modifier: Patients with knee effusion/synovitis showed a greater improvement in KOOS4 after early surgery compared to exercise therapy.
▶️ The mean improvement was 11.1 points in favour of early surgery (p=0.07), which was considered clinically significant.
▶️ This suggests that signs of persistent inflammation (inflammatory phenotype) of the knee may predict better outcomes with surgery.
🔑 No Effect Modification by Tear Type: Contrary to expectations, patients with complex tears did not benefit more from early surgery than those with simple tears.
▶️ The difference between complex and simple tears was minimal (4.5 vs. 4.8 points on KOOS4, p=0.95), suggesting that both groups responded similarly to treatment.
🔑 No Effect Modification by Meniscus Location: The study hypothesized that medial meniscus tears would respond better to surgery due to biomechanical forces acting more on the medial compartment.
▶️ However, the results showed the opposite trend, with lateral tears showing a greater response to surgery (9.6 points) than medial tears (4.6 points, p=0.47).
▶️ This unexpected finding challenges previous assumptions about meniscus biomechanics.
💡 Discussion and Clinical Implications
▶️ Knee effusion/synovitis may be an MRI-defined effect modifier on patient-reported outcomes in favour of early meniscal surgery. These findings reinforce the importance of personalized treatment planning, considering MRI findings alongside patient symptoms (mechanical symptoms may be better improved by early surgery, https://pubmed.ncbi.nlm.nih.gov/36878666/) and patient preferences.
▶️ The lack of effect modification by tear type and location suggests that meniscal tear morphology alone should not determine treatment strategy.
▶️ The findings challenge the traditional assumption that medial meniscus tears are more problematic than lateral tears.
▶️ Exercise therapy remains a viable first-line treatment for most young adults with meniscal tears, given that complex tears did not significantly favour surgery.
⭕ Limitations
▶️ The study was not powered to detect small subgroup differences, meaning that some trends may not have reached statistical significance due to the sample size.
▶️ MRI scans were conducted at multiple centers, which could introduce variability in image interpretation.
▶️ Long-term effects beyond 12 months were not analyzed, leaving uncertainty about the durability of the observed benefits.
