Meniscus Injury Summary:
The menisci are two semi-lunar shaped pieces of cartilage that lie between the femoral condyles and the tibia in the knee joint. These structures are commonly injured in athletes due to the strain on the knee during cutting, twisting and pivoting movements. Meniscal tears can also be caused by degenerative changes in the knee joint, especially in the middle-aged and older adult population1. The symptoms of a torn meniscus typically present as knee “catching” or “locking”, limited joint mobility about the knee, daily knee pain lasting more than one month, effusion (swelling), a feeling of instability in the knee and tenderness around the joint line2. For patients who have had a meniscal tear repaired arthroscopically, typical post-operative limitations include pain, swelling and limited range of motion3. Modalities addressing swelling, restricted range of motion and pain are similar for both conservative treatment and post-surgical rehabilitation.
Guide to Physical Therapy Practice:
According to the APTA's Guide to Physical Therapist Practice, there are two practice patterns that apply to meniscal tears:
- Pattern 4I: Impaired Joint Mobility, Motor Function, Muscle Performance, and Range of Motion Associated With Bony or Soft Tissue Surgery
- Pattern 4D: Impaired Joint Mobility, Motor Function, Muscle Performance, and Range of Motion Associated With Connective Tissue Dysfunction.
The Guide states that “Over the course of 1 to 8 months (for pattern 4I) or 2 to 6 months (for pattern 4D), patient/client will demonstrate optimal joint mobility, motor function, muscle performance, and range of motion and the highest level of functioning in home, work (job/school/play), community, and leisure environments” and will accomplish this in 6-70 visits (for pattern 4I) or 3-36 visits (for pattern 4D).
Link to the Guide to PT Practice Pattern 4I
Link to the Guide to PT Practice Pattern 4D
Therapeutic Exercise:
There is limited research on specific exercise guidelines for conservative management of meniscal tears and post-operative therapeutic exercise guidelines. Most research studies have cited that it is important to engage the patient in strengthening exercises, stretching exercises, and modalities and medications such as NSAIDs to decrease inflammation4,5,6.The following chart is taken from Pyne3 demonstrating a treatment protocol post-surgical meniscus repair to maintain strength in the knee while following specific weight-bearing precautions and bracing schedule described by:
• Week 1: Partial weight-bearing as tolerated with crutch assistance
• Week 2: Full weight-bearing
• Week 1-3: Hinged range of motion brace set to allow 0-45 degrees of knee flexion
• Weeks 3-6: Hinged knee brace set at 0-90 degrees of flexion
• Week 6: Patient should have obtained full range of motion
• Weeks 6-8: Brace still used but no range limitations set
• After week 8: Discontinue brace use

Brigham and Women’s Hospital7 also has a set of guidelines that are more specific for post-operative repair of the meniscus:
Phase I –Maximum Protection- Weeks 1-6:
Goals:
• Diminish inflammation and swelling
• Restore ROM
• Reestablish quadriceps muscle activity
Stage 1: Immediate Postoperative Day 1- Week 3
• Ice, compression, elevation
• Electrical muscle stimulation
• Brace locked at 0 degrees
• ROM 0-90: Motion is limited for the first 7-21 days, depending on the development of
scar tissue around the repair site. Gradual increase in flexion ROM is
based on assessment of pain and site of repair (0-90 degrees).
• Patellar mobilization
• Scar tissue mobilization
• Passive ROM
Exercises
• Quadriceps isometrics
• Hamstring isometrics (if posterior horn repair, no hamstring exercises for
6 weeks)
• Hip abduction and adduction
• Weight-bearing as tolerated with crutches and brace locked at 0 degrees
• Proprioception training with brace locked at 0 degrees
Stage 2: Weeks 4-6
• Progressive resistance exercises (PREs) 1-5 pounds.
• Limited range knee extension (in range less likely to impinge or pull on repair)
• Toe raises
• Mini-squats less (than 90 degrees flexion)
• Cycling (no resistance)
• PNF with resistance
• Unloaded flexibility exercisesPhase II: Moderate Protection- Weeks 6-10
Criteria for progression to phase II:
• ROM 0-90 degrees
• No change in pain or effusion
• Quadriceps control (MMT 4/5)
Goals:
• Increased strength, power, endurance
• Normalize ROM of knee
• Prepare patients for advanced exercises
Exercises:
• Strength- PRE progression
• Flexibility exercises
• Lateral step-ups
• Mini-squats
Endurance Program:
• Swimming (no frog kick), pool running- if available
• Cycling
• Stair machine
Coordination Program:
• Balance board
• Pool sprinting- if pool available
• Backward walking
• PlyometricsPhase III: Advanced Phase- Weeks 11-15
Criteria for progression to phase III:
• Full, pain free ROM
• No pain or tenderness
• Satisfactory clinical examination
• SLR without lag
• Gait without device, brace unlocked
Goals:
• Increase power and endurance
• Emphasize return to skill activities
• Prepare for return to full unrestricted activities
Exercises:
• Continue all exercises
• Increase plyometrics, pool program
• Initiate running program
Return to Activity: Criteria
• Full, pain free ROM
• Satisfactory clinical examinationCriteria for discharge from skilled therapy:
1) Non-antalgic gait
2) Pain free /full ROM
3) LE strength at least 4/5
4) Independent with home program
5) Normal age appropriate balance and proprioception
6) Resolved palpable edema
When analyzing conservative treatment, Herrlin et al.1 found that exercises such as calf raises, lunges, hamstring curls, long arc quads, stair walking, rocker board balance, stationary biking, and stretching of the knee flexors and extensors over an 8 week time period produced the same amount of improvement as arthroscopic surgery in a population of middle-aged patients with degenerative damage to the meniscus. It is important to note that surgery may still be indicated if conservative treatment is ineffective.

Transcutaneous Electrical Nerve Stimulation (TENS):
Although transcutaneous electrical nerve stimulation is a common modality used to treat post-operative pain, acute pain and chronic pain, the evidence available shows that there is no difference in pain level after using TENS for any of the above types of pain.8 In a randomized controlled trial by Breit and Van der Wall9, researchers looked at the amount of pain medication a patient used via PCA pump after total knee arthroplasty. The experimental group was given TENS treatment while a control group did not receive TENS treatment. The results showed no difference in the amount of pain medication the patients self-administered between groups. Although this study examined the use of TENS post-knee arthroplasty, the data can be loosely translated to post-operative meniscus repair since the limitations associated with both surgeries (limited ROM, swelling, and pain) are similar. There is no further research available on the use of TENS for conservative or surgical treatment of meniscal tears.

Ultrasound:
There is little evidence suggesting that ultrasound treatment is effective in treating the impairments following meniscus tears. In one case report by Muche10, a patient who had been in a coma for a month and a half complained of knee pain upon waking up which was diagnosed as a posterior horn meniscus tear. He was treated for the knee pain with RICE (rest, ice compression and elevation) treatment as well as ultrasound. Researchers report that the ultrasound helped this patient make quick functional gains initially and had a reduction in pain. However, since this study was a case report with no control group to compare to, it is difficult to tell whether the initial functional gains and pain relief can be attributed to the ultrasound or to the RICE therapy or to any other factors. There is still limited evidence to show the effectiveness in ultrasound treatment to reduce the limitations associated with meniscal tears.
Cryotherapy:

Cryotherapy involves the application of a cold agent (commonly ice) to the affected area with the idea that the cold will help to decrease pain and swelling associated with acute injuries and post-surgical wounds. In a quasi-experimental study by Fang et al11 patients who underwent arthroscopic knee surgery were either given ice in a plastic bag applied to the surgical site or no ice. Patients in the ice group were treated with cryotherapy for 3 50-minute intervals over a 3 hour time span beginning immediately after the anesthesia wore off. The results showed that those who were given ice had a greater decrease in pain over the 3-hour time period than those who were not given ice. This study applies to clinical practice by showing that ice provided in a simple plastic bag is effective in decreasing pain and is also a cost-effective and easy modality that can be used in the hospital.

Neuromuscular Electrical Stimulation (NMES):
Neuromuscular electrical stimulation involves the delivery of an electrical current to muscle tissue in order to stimulate a contraction. The idea is that by stimulating a contraction in the quadriceps femoris muscle in a patient who has had a meniscus tear, the muscle will “relearn” how to contract effectively and therefore increase strength and endurance12. In a systematic review of multiple randomized controlled trials, Bax, Staes and Verhagen12 found that although NMES is used in a variety of therapeutic settings, there is a lack of evidence to support its effectiveness. These authors found that volitional contraction of the quadriceps femoris muscle through therapeutic exercises is more effective than NMES of the quads. The only situation in which this modality has been shown to be superior to volitional contraction is when the patient has a casted thigh, or when the patient is unable to comply with the prescribed volitional therapeutic exercises.
Summary:
The standard of care for both conservative treatment and post-surgical rehabilitation of meniscus tears remains controversial in the literature. Based on the current research, the most common limitations associated with meniscus tears are impaired range of motion, swelling (effusion) and pain3. Therapeutic exercises for the hip, knee and ankle are used to address impaired range of motion, any functional limitations and any strength deficits associated with the meniscus lesion, as well as increase circulation to help eliminate swelling3,4,5,6,7. Conservative treatment for meniscal tears can be effective within 8 weeks1 whereas therapy for post-surgical meniscus repair generally lasts about 15 weeks7. While other modalities (ie; TENS, ultrasound, cryotherapy and NMES) are commonly used in a variety of clinical settings8,9,10,11,12, the use of ice is the only method shown to be useful in reducing pain and swelling when combined with therapeutic exercise11.
References:
1. Herrlin S, Hllander M, Wange P, Weidenhielm L, Werner S. Arthroscopic or conservative treatment of degenerative medial meniscal tears: A prospective randomised trial. Knee Surgery, Sports Traumatology, Arthroscopy. 2007;15(4):393-401.
2. Ercin E, Kaya I, Sungur I, Demirbas E, Ugras A, Cetinus E. History, clinical findings, magnetic resonance imaging, and arthroscopic correlation in meniscal lesions. Knee Surgery, Sports Traumatology, Arthroscopy. 2011.
3. Pyne S. Current progress in meniscal repair and postoperative rehabilitation. Current Sports Medicine Reports. 2002;1(5):265-271.
4. Poulsen M, Johnson D. Meniscal injuries in the young, athletically active patient. The Physician and Sports Medicine. 2011;39(1):123-130.
5. Greis P, Holmstrom M, Bardana D, Burks R. Meniscal injury: II. management. J Am Acad Orthop Surg. 2002;10(3):177-187.
6. Lim HC, Bae JH, Wang JH, Seok CW, Kim MK. Non-operative treatment of degenerative posterior root tear of the medial meniscus. Knee Surgery, Sports Traumatology, Arthroscopy. 2010;18:535-539.
7. Brigham and Womens Hospital Mensicus Repair Protocol: Adopted from Brotzman SB, Wilk KE, Clinical Orthopeadic Rehabilitation. Philadelphia, PA: Mosby Inc; 2003:315-319. http://www.brighamandwomens.org/Patients_Visitors/pcs/rehabilitationservices/Physical%20Therapy%20Standards%20of%20Care%20and%20Protocols/Knee%20-%20Meniscal%20repair%20protocol.pdf. Updated 2007 Accessed 2012.
8. Johnson MI. Does transcutanous electrical nerve stimulation (TENS) work? Clinical Effectiveness in Nursing. 1998;2(3):111-120.
9. Breit R, Van der Wall h. Transcutaneous electrical nerve stimulation for postoperative pain relief after total knee arthroplasty. Journal of Arthroplasty. 2004;19(1):45-48.
10. Muche JA. Efficacy of therapeutic ultrasound treatment of a meniscus tear in a severely disabled patient: A case report. Arch Phys Med Rehabil. 2003;84:1558-1559.
11. Fang L, Hung CH, Wu SL, Fang SH, Stocker J. The effects of cryotherapy in relieving postarthroscopy pain. J Clin Nurs. 2012:21(5-6);636-643.
12. Bax L, Staes F, Verhagen A. Does neuromuscular electrical stimulation strengthen the quadriceps femoris? A systematic review of randomised controlled trials. Sports Med. 2005;35(3):191-212.