A 48-year-old man presents to your office for follow-up of right knee pain that has been bothering him for the last 12 months. He denies any trauma or inciting incident for the pain. On physical exam, he does not have crepitus, but has medial joint line tenderness of his right knee. A magnetic resonance image (MRI) shows a partial, medial meniscal tear. Do you refer him to Physical Therapy (PT) or Orthopedics for arthroscopy and repair?
The meniscus—cartilage in the knee joint that provides support, stability, and lubrication to the joint during activity—can tear during a traumatic event or because of degeneration over time. Traumatic meniscal tears typically happen to younger adults and teens (<30 years of age) during sports, such as basketball and soccer,whereas degenerative meniscal tears generally present in patients ages 40 to 60 years.2,3 The annual incidence of all meniscal tears is 79 per 100,000.4 While some physicians can diagnose traumatic meniscal tears based on history and physical examination, degenerative meniscal tears are generally more challenging, and typically warrant an MRI for confirmation.3
Meniscal tears can be treated either conservatively, with supportive care and exercise, or with surgery. Unfortunately, there are no national orthopedic guidelines available to help direct care. In one observational study of surgery as treatment for both traumatic and degenerative meniscal tears, 95 out of 117 patients (81.2%) were generally satisfied with this treatment at the 4-year follow-up, with higher satisfaction in the traumatic meniscal tear group than in the degenerative tear group.5
Two systematic reviews of surgery vs nonoperative management or sham therapies found no additional benefit of surgery for meniscal tears in a variety of patients with and without osteoarthritis.6,7 However, both studies were of only moderate quality because of the number of patients in the nonoperative groups who ultimately obtained surgery. And neither of the studies directly compared surgery to nonoperative management.6,7
Yet another investigation, a multicenter, randomized, double-blind, sham-controlled study conducted in Finland involving 146 patients, compared sham surgery to arthroscopic partial meniscectomy. Both groups received instruction on performing post-procedure exercises, and both groups had similar and marked improvement in pain and function.8
Clinical practice recommendations devised from a systematic and vast review of the literature recommend that the decision for surgery be based on patient-specific factors such as symptoms, age, mechanism of tear, extent of damage, and occupational/social/activity needs.9
Exercise is as good as—and in one way, better than—surgery
The current randomized controlled superiority trial compared exercise therapy to arthroscopic partial meniscectomy in patients ages 35 to 60 years presenting to the orthopedic departments of 2 hospitals in Norway with unilateral knee pain for more than 2 months and an MRI-delineated medial meniscal tear. Patients were included only if they had radiographic evidence of minimal osteoarthritis (Kellgren-Lawrence classification grade ≤2). Exclusion criteria were acute trauma, locked knee, ligament injury, and knee surgery in the same knee within the previous 2 years.
The primary outcomes were change in patient-reported knee function as determined by overall knee injury and osteoarthritis outcome score (KOOS4) after 2 years and thigh muscle strength at 3 months as measured by physiotherapists. The KOOS4 consists of 4 out of the 5 KOOS subscales: pain, other symptoms (swelling, grinding/noise from the joint, ability to straighten and bend), function in sports/recreation, and knee-related quality of life (QOL). This study utilized the average score of each subscale.
Secondary outcomes were the 5 individual KOOS subscales (the 4 previously mentioned plus activities of daily living [ADLs]), as well as thigh muscle strength and lower extremity performance test results.
Methods. Testing personnel were blinded to group allocation; participants wore pants or neoprene sleeves to cover surgical scars. A total of 140 patients were randomized to either 12 weeks (24-36 sessions) of exercise therapy alone or a standardized arthroscopic partial meniscectomy with written and oral encouragement upon discharge to perform simple exercises at home 2 to4 times daily (to regain range of motion and reduce swelling).
Results. The overall mean improvement in KOOS4 score from baseline at 2 years was similar between the exercise group and the meniscectomy group (25.3 points vs 24.4 points, respectively; mean difference [MD], 0.9; 95% confidence interval [CI], -4.3 to 6.1; P=.72). Additionally, muscle strength (measured as peak torque flexion and extension and total work flexion and extension) at both 3 and 12 months showed significant objective improvements favoring exercise therapy.
Secondary outcomes comparing the change from baseline of KOOS subscale scores showed 4 of the 5 having non-significant differences (pain, ADL, sports/recreation, and QOL). Only the symptoms subscale had a significant difference favoring exercise therapy (MD, 5.3 points; 95% CI, 0.5 to 10.2; P=.03), which was likely clinically insignificant when using a grading scale of 0 to 100.
Of those patients allocated to exercise therapy alone, 19% crossed over and underwent surgery during the 2 years of the study.