Can baseline MRI findings identify who responds better to early surgery versus exercise and education in young patients with meniscal tears? A subgroup analysis from the DREAM trial

Key Points

1. Knee effusion/synovitis on MRI was associated with better outcomes from early surgery compared to exercise therapy for young patients with meniscal tears.
2. The type of meniscal tear (simple vs. bucket handle/complex) and the location of the tear (medial vs. lateral) did not significantly influence whether patients benefited more from surgery or exercise therapy.

BACKGROUND & OBJECTIVE

Arthroscopic surgery on the meniscus is one of the most common orthopedic procedures, but recent randomized controlled trials have shown that early surgery is not superior to exercise therapy for meniscal tears in young adults. However, it is possible that specific subgroups of patients might benefit more from surgery than exercise.

This study aimed to investigate whether baseline MRI findings could identify subgroups of young patients with meniscal tears who would respond better to early surgery versus exercise therapy.

Arthroscopic surgery on the meniscus is one of the most common orthopedic procedures.

Patients with knee effusion/synovitis on MRI showed greater improvement with surgery and the type and location of meniscal tear did not influence treatment outcomes, however, these findings should be interpreted cautiously.

METHODS

The researchers conducted a secondary analysis of data from the Danish RCT on Exercise versus Arthroscopic Meniscal surgery for young adults (DREAM) trial, which included 121 patients aged 18-40 years with MRI-confirmed meniscal tears.

They investigated three different ways to subgroup the patients based on MRI:

1. Type of meniscal tear (simple vs. bucket handle/complex)
2. Location of meniscal tear (medial vs. lateral)
3. Presence of knee effusion/synovitis (yes vs. no)

The primary outcome was change from baseline to 12 months in the KOOS score (average of pain, symptoms, function in sport/recreation, and quality of life, ranging from 0-100, with higher scores being better). A difference of 10 points or more was considered clinically relevant.

Data was analyzed using a linear mixed model adjusted for randomization stratification factors and age.

RESULTS

Data from all 121 participants (60 in surgery group, 61 in exercise group) were analyzed. Mean age was 29.7 years, 28% were female, and 57% had symptoms lasting between 0-six months.

The only potential effect modifier observed was knee effusion/synovitis, with its presence associated with an 11-point improvement in the KOOS score for the surgery group compared to just a 0.3-point improvement for the exercise group (difference = 10.8 points, p = 0.07).

The type of meniscal tear and the affected meniscus showed no significant effect modification, with differences that did not reach clinical relevance and with p-values of 0.95 and 0.47, respectively.

LIMITATIONS

The DREAM trial was not adequately powered for subgroup analysis. A statistically significant subgroup interaction in an RCT typically requires a sample size approximately four times larger than needed to detect a mean effect of the same size.

MRI scans were conducted using different scanners across seven hospital departments, which could result in some variation in the visualization of findings, although the risk of significant differences affecting the results was expected to be small.

The authors chose to focus on three specific findings and grouped all bucket handle, displaced, and complex tears together, which might have missed identifying specific types of complex tears that could benefit from early surgery.

CLINICAL IMPLICATIONS

Arthroscopic surgery targeting the meniscus remains one of the most common orthopedic procedures, with more than one million surgeries performed each year worldwide (1). Previous randomized controlled trials, including the DREAM trial, have shown that early arthroscopic meniscal surgery is not superior to exercise therapy for young adults with meniscal tears (2, 3). However, it is thought that specific subgroups might benefit more from surgery than exercise (4).

This secondary analysis aimed to identify whether specific MRI findings could predict which patients would benefit more from early surgery versus exercise therapy. The study found that patients with knee effusion/synovitis on MRI showed greater improvement with surgery (11-point difference on KOOS scale). The type and location of meniscal tear did not appear to influence treatment outcomes.

However, these findings should be interpreted cautiously as the study was not powered for subgroup analysis and tested multiple subgroups, increasing the risk of chance findings. The effusion/synovitis result, though clinically relevant, did not reach statistical significance (p=0.07) and requires validation in larger studies before influencing clinical practice.

+STUDY REFERENCE

'Can Baseline MRI Findings Identify Who Responds Better to Early Surgery Versus Exercise and Education in Young Patients With Meniscal Tears? A Subgroup Analysis From the DREAM Trial.' J Orthop Sports Phys Ther.

SUPPORTING REFERENCE

1. Howard DH. Trends in the use of knee arthroscopy in adults. JAMA Intern Med. 2018;178:1557-1558.
2. Clausen SH, Skou ST, Boesen MP, et al. Two-year MRI-defined structural damage and patient-reported outcomes following surgery or exercise for meniscal tears in young adults. Br J Sports Med. 2023;57:1566-1572.
3. Skou ST, Hölmich P, Lind M, et al. Early surgery or exercise and education for meniscal tears in young adults. NEJM Evid. 2022;1:EVIDoa2100038.
4. Damsted C, Thorlund JB, Hölmich P, et al. Effect of exercise therapy versus surgery on mechanical symptoms in young patients with a meniscal tear: a secondary analysis of the DREAM trial. Br J Sports Med. 2023;57:521-527.