Dr. Stan Lubin (biography and disclosures)
What I did before
In the 1970’s if you had a suggestive history, physical exam, and no osteoarthritis you would probably have a complete meniscectomy. Often the knee pain persisted postoperatively. Then complete meniscectomy was shown to be associated with a significantly increased risk of osteoarthritis (1).
More recently in a person with:
- knee pain;
- a history of instability – locking or giving way;
- a positive physical examination – McMurray or Thessaly test positive(2);
- an MRI indicating meniscal damage;
- no evidence of osteoarthritis,
I would refer to an orthopedic surgeon for consideration of a partial meniscectomy. Often the knee pain persisted postoperatively.
What changed my practice
While I knew that there was a relatively high rate of false positive results with MRI’s a 2008 NEJM study cast significant doubt on our reliance on knee MRI’s. 991 persons from Framingham, Massachusetts were drawn from census-tract data and random-digit telephone dialing. Subjects were 50 to 90 years of age and ambulatory. Selection was not made on the basis of knee or other joint problems. MRI’s of the right knee were obtained from all subjects (57% women). Symptoms involving the right knee were evaluated by questionnaire. One radiologist reviewed all MRI’s. On MRI the prevalence of a meniscal tear was 63% among those with knee pain, aching, or stiffness on most days and 60% among those without these symptoms. The corresponding prevalences among persons without radiographic evidence of osteoarthritis were 32% and 23%. Sixty-one percent of the subjects who had meniscal tears in their knees had not had any pain, aching, or stiffness during the previous month. In summary, a person without knee pain was almost as likely to have a meniscal tear on MRI as a person with knee pain. (3,4)
In a more recent NEJM study researchers conducted a multicenter, randomized, double-blind, sham-controlled trial in 146 patients 35 to 65 years of age who had knee symptoms consistent with a degenerative (non-traumatic) medial meniscus tear and no knee osteoarthritis. Patients were randomly assigned to arthroscopic partial meniscectomy or sham surgery. At 12 months after the procedure pain scores were the same in the arthroscopic and sham arthroscopic groups.(4) This study casts doubt on the utility of partial meniscectomy in reducing pain and improving function for degenerative meniscal tears (but not traumatic tears).
What I do now
- I ask all patients with knee pain if they ever had a significant knee injury at any time in their life. If after a knee injury they have had a significant effusion, prolonged pain, locking, or instability, or they have abnormal findings such as a positive drawer test or McMurray test I still order an x-ray. If the x-ray shows no osteoarthritis I order an MRI. If the MRI is abnormal I refer the patient to an orthopedic surgeon.
- If there is no history of knee trauma and the physical examination is normal I usually temporize by recommending quadriceps exercises. A good proportion of knee pain is caused by patellofemoral syndrome. There is reasonable evidence that quadriceps exercises reduce knee pain in this condition (6, 7).
- I obtain a knee MRI only if the symptoms are consistent with a specific lesion. There is no guarantee that a patient’s pain is from the meniscus, even with a positive MRI, because meniscal findings on knee MRI do not correlate well with pain. I do not assume that the meniscus is the root of the patient’s problem, even with a positive MRI.
- Much as I do for evaluating a lumbar disc I try to determine if the history, physical, x-ray and MRI findings are consistent.
- I am more conservative in referring patients for meniscectomy. I advise patients that arthroscopy is the gold standard and that meniscectomy may not be effective in eliminating or reducing knee pain.
- Roos H, Laurén M, Adalberth T, Roos EM, Jonsson K, Lohmander LS. Knee osteoarthritis after meniscectomy: prevalence of radiographic changes after twenty‐one years, compared with matched controls. Arthritis & Rheumatism 1998; 41(4): 687-693. (Request from CPSBC) http://www.ncbi.nlm.nih.gov/pubmed/9550478
- Harrison BK, Abell BE, Gibson TW. The Thessaly test for detection of meniscal tears: validation of a new physical examination technique for primary care medicine. Clinical Journal of Sport Medicine 2009; 19(1): 9-12. (Request from CPSBC or view with UBC) http://www.ncbi.nlm.nih.gov/pubmed/19124977
- Englund M, Guermazi A, Gale D, Hunter DJ, Aliabadi P, Clancy M, Felson DT. Incidental meniscal findings on knee MRI in middle-aged and elderly persons. New England Journal of Medicine 2008; 359(11): 1108-1115. http://www.nejm.org/doi/full/10.1056/NEJMoa0800777
- Graber MA, Dachs R, Darby-Stewart A. Clinical significance of meniscal damage on knee MRI. American Family Physician 2011; 83(10): 1160. http://www.aafp.org/afp/2011/0515/p1160.html
- Sihvonen R, Paavola M, Malmivaara A, Itälä A, Joukainen A, Nurmi H, Kalske J, Järvinen TL. Arthroscopic partial meniscectomy versus sham surgery for a degenerative meniscal tear. New England Journal of Medicine 2013; 369(26): 2515-2524. http://www.nejm.org/doi/full/10.1056/NEJMoa1305189
- Heintjes E, Berger MY, Bierma-Zeinstra SM, Bernsen RM, Verhaar JA, Koes BW. Exercise therapy for patellofemoral pain syndrome. Cochrane Database Syst Rev 2003; 4. (Request from CPSBC) http://www.ncbi.nlm.nih.gov/pubmed/14583980?dopt=Abstract
- Kooiker L, Van De Port IG, Weir A, Moen MH. Effects of physical therapist–guided quadriceps-strengthening exercises for the treatment of patellofemoral pain syndrome: a systematic review. Journal of Orthopaedic & Sports Physical Therapy 2014; 44(6): 391-B1. http://www.jospt.org/doi/abs/10.2519/jospt.2014.4127#.U3P2kPldWKQ