Meniscal Injuries Overview

Meniscal Injuries: Mechanisms

• Sudden changes in direction with the foot fixed on the ground (e.g., cutting, pivoting) are common causes
• Hyperflexion (e.g., landing, activities by certain professions like miners, plumbers, wrestlers) can cause injuries
• High-impact compression loads can also lead to injuries
• Injuries can be related to mechanisms involving the MCL or ACL

Meniscal Injuries: Signs and Symptoms

• Severe pain immediately following injury, with swelling (effusion) developing within hours
• Feeling of instability or giving way on the affected knee
• Intermittent pain and swelling (effusion) can occur later
• Locking of the knee joint is a possible symptom
• Tenderness along the joint line is a possible indication
• Positive McMurray or Apley compression tests may indicate a meniscal tear
• Limited range of motion (ROM) and premature end-feel
• Symptoms exacerbated by deep squatting

Decision-making: Leave Alone

• Partial thickness tears of the meniscus, especially short peripheral tears, that don't disrupt joint mechanics might not require treatment
• Stable meniscus in an otherwise unstable knee might be observed
• Degenerative meniscus in a degenerative knee might be observed

Partial Menisectomy

• A procedure to remove a portion of the meniscus is recommended when a meniscal tear disrupts the knee mechanics and the patient is not a surgical candidate for repair
• Debridement involves removing as little of the damaged tissue as possible

Rehabilitation Following Arthroscopic Debridement

• Muscle strengthening and joint mobility exercises, including isometrics, active range of motion (AROM), and posterior chain mobilization (PF mobilization)
• Immediately following surgery, soft tissue manipulation of the portal scars should be done. This is performed when the incisions are healed and ready.
• Progress to progressive resistance exercise (PREs) when tolerated
• Add neuromuscular electrical stimulation (NMES) when appropriate

Rehabilitation Following Arthroscopic Debridement: Ambulation

• Partial Weight Bearing After Surgery (PWBAT) is permitted immediately
• Progress to full weight bearing (FWB) when walking without limping, which usually takes 1 to 2 weeks

Rehabilitation Following Arthroscopic Debridement: Return to Activity

• Return to running on a treadmill around 3-4 weeks if quad strength is over 70% and there is no joint pain or swelling
• Progress to level surface running, sprinting, and agility training as tolerated
• Full activity usually resumes within 6 weeks, with quad strength above 85%

Meniscal Repair

• Repair is considered if the lesion is in an area with good blood supply (vascularization)
• Lesions are at least 1 cm in length

Rehabilitation Following Meniscal Repair: Muscles and Mobility

• Limited range of passive and active range of motion (PROM & AROM) for the first 2-3 weeks (0-90 degrees), gradually progress to full ROM within 6-8 weeks
• Isometric exercises should be started immediately after surgery
• No resisted hamstring or closed chain exercises for the first six weeks
• Progress to more aggressive strengthening exercises (e.g., closed-chain exercises) after 6 weeks. Avoid resisted open-chain hamstring exercises

Rehabilitation Following Meniscal Repair: Ambulation

• Weight-bearing as tolerated (WBAT) with the brace locked in extension for the first 1-2 weeks after surgery.
• When the brace is unlocked, gradually wean off crutches and progress to full weight-bearing (FWB) ambulation.

Rehabilitation Following Meniscal Repair: Return to Activity

• Start a graded running program (begin on a treadmill) after 3-6 months, depending on quad strength, pain, and swelling
• Full activity can be expected after 6 months or more depending on the progress in the running and agility program
• Activity restrictions after surgery and too much early activity may hinder recovery

Meniscal Repair of Avascular, Central Region

• Meniscal repair of avascular, central regions are more common due to increased emphasis on preserving the meniscus
• Modifications to surgical techniques, like fibrin clot development, and rasping of synovial fringes to create vascular access channels improve healing
• Outcomes are encouraging, with high success rates for these procedures.

Meniscal Repair of Avascular, Central Region: Specific Data

• Noyes, et al. (2002) reported successful outcomes with 75% of patients having no symptoms at an average follow-up of 18 to 51 months following repair in individuals under 19 years of age.
• Noyes, et al. (2000) reported 26/30 patients (87%) were symptom-free after 34 months post-surgery in individuals 40 years or older.

Meniscal Repair of Avascular, Central Region: Rehabilitation Protocol (Noyes, 2002)

• Immediate knee motion (0-90 degrees)
• Flexion to 120 degrees by 3-4 weeks
• Flexion to 135 degrees by 5-6 weeks
• Crutches for the first 4 weeks, then progress to touch weight bearing
• Full weight bearing (FWB) by 6 weeks
• No deep squatting, running, jumping, cutting, or twisting for 6 months