What is the recommended treatment for an adult patient with a confirmed knee meniscus injury via arthroscopy?

Arthroscopic Surgery for Knee Meniscus Injuries: Evidence-Based Recommendations

Primary Recommendation

For adults with degenerative knee meniscus tears confirmed on arthroscopy, conservative management with exercise therapy is strongly recommended over arthroscopic surgery, as surgery provides no sustained benefit in pain or function and exposes patients to unnecessary surgical risks. 1, 2

Critical Distinction: Degenerative vs. Traumatic Tears

The management approach fundamentally depends on whether the meniscus injury is degenerative or truly traumatic:

Degenerative Meniscus Tears (Most Common in Adults >35 Years)

Do not perform arthroscopic surgery for patients with degenerative knee disease, even when meniscal tears are present on imaging. 1, 3 This strong recommendation applies to:

• Patients with or without radiographic evidence of osteoarthritis 1
• Patients with mechanical symptoms (clicking, catching, intermittent "locking") 4
• Patients with sudden but non-traumatic symptom onset 1
• Patients of any age with degenerative changes 1

The evidence is clear: Less than 15% of patients experience small improvements at 3 months post-surgery, and these benefits completely disappear by 1 year. 4, 3 Meanwhile, most patients improve significantly with conservative management alone. 3

The Single Exception: True Locked Knee

Arthroscopic surgery may be considered only when there is objective inability to fully extend the knee (true mechanical locking), not subjective sensations of catching or clicking. 1, 4 This represents a loose body or unstable meniscal fragment causing genuine mechanical obstruction.

Conservative Management Algorithm (First-Line Treatment)

Implement the following evidence-based conservative approach:

Immediate interventions:

• Weight loss if BMI >25 kg/m² 2, 3
• Structured exercise therapy and physical therapy 1, 3
• Oral or topical NSAIDs for pain control 2, 3

Second-line options if inadequate response:

• Intra-articular corticosteroid injections (provides 1-2 weeks of benefit) 3
• Watchful waiting, as degenerative knee disease symptoms naturally fluctuate and often improve over time 1, 2

Duration: Continue conservative management for at least 3-6 months before considering any surgical consultation. 3

Why Arthroscopy Fails in Degenerative Disease

The BMJ guideline, based on 13 randomized controlled trials involving 1,665 patients, demonstrates that arthroscopic surgery:

• Does not improve pain or function compared to exercise therapy at 1 year 1
• Exposes patients to surgical risks including infection (septic arthritis), thrombophlebitis, anesthetic complications, and vasovagal reactions 2, 3
• Requires 2-6 weeks recovery and 1-2 weeks off work 1
• Provides no advantage even in patients with minimal radiographic osteoarthritis or prominent mechanical symptoms 1

Critical Pitfalls to Avoid

Pitfall #1: Assuming imaging findings equal surgical indications Meniscal tears on MRI are extremely common incidental findings in adults >35 years and are usually not the source of symptoms. 4, 3 The presence of a tear does not justify surgery.

Pitfall #2: Misinterpreting mechanical symptoms Clicking, catching, and intermittent "locking" sensations are typically pain and stiffness, not true mechanical obstruction. These symptoms respond equally well to conservative treatment. 4, 3 Only objective inability to fully extend the knee warrants surgical consideration.

Pitfall #3: Operating on older patients In patients >50 years, arthroscopic meniscectomy carries increased risks and provides no sustained benefit due to the high prevalence of degenerative changes. 2, 3 The American Academy of Orthopaedic Surgeons issues a Grade A recommendation (highest level) against arthroscopy in symptomatic knee osteoarthritis. 3

Special Consideration: Young Traumatic Injuries

The guidelines explicitly exclude young patients with acute sports-related injuries or major trauma from the recommendation against surgery. 1 For these patients with truly traumatic, repairable meniscal tears in vascularized zones, meniscal repair (not meniscectomy) should be considered to prevent early osteoarthritis. 5, 6

However, even in this population, peripheral well-vascularized tears may heal with conservative management. 6

Patient Communication Framework

When discussing arthroscopy with patients who have degenerative meniscus tears:

• Explain that meniscal tears are common age-related findings, like "wrinkles on the inside of the knee" 4
• Emphasize that 13 high-quality trials show no lasting benefit from surgery 1
• Clarify that their symptoms will likely improve with exercise therapy alone 1, 3
• Discuss surgical risks including infection and blood clots 2, 3
• Address cost and recovery time (2-6 weeks off activities) 1, 2