N.R. is a 49-year-old male who is referred to an orthopedic surgeon by his primary care provider for right knee pain which is affecting mobility and function. Pt. is active and healthy, exercises six days a week in training for triathlons which he competes in 5-6 times/year. He denies any previous musculoskeletal problems, except for a compound, spiral right tibial fracture when he was 18 yrs. old resulting from a skiing accident. Pt. has recently been taking part in military-type training sessions run for civilians, which involve rigorous lateral movement. He has experienced increasing pain and swelling in the right knee for the past two weeks. Pain is exacerbated when N.R. performs twisting or pivoting movements. N.R. states that he does not feel his knee is moving properly, is ‘not in proper alignment’, and is very stiff.

Upon examination, it is noted that right lower leg is deviated slightly from expected position. N.R. reports that tibia was in that position after the fracture when he was 18 yrs. old.  Substantial effusion is noted on the interior side of right knee. Examination for joint line tenderness was positive on the medial aspects of the knee, with pain experienced on full flexion and extension of the knee in a supine position (McMurray test). The Thessaly test was also performed and was positive for pain. (The Thessaly test is a good indicator for meniscal tears as it mimics loading forces on the knee. The patient stands on one leg with the knee flexed to 20° while holding the examiner’s hands for stability, and internally and externally rotates the knee of the supporting leg.) PA and lateral X-rays were done which showed a large contusion to the distal end of the femur. MRI confirmed a tear of the medial meniscus. Also noted on imaging was the wearing of cartilage on the distal end of the femur in a pattern that suggested long-standing misalignment of tibia, possibly due to post-fracture setting of tibia.

Conservative treatment involving resting the knee and application of ice was undertaken. This allowed for the femur contusion to resolve and to determine how much of the pain was originating from this area. After twelve weeks, arthroscopy was done for a partial meniscectomy and repair of the meniscal tear, as pain, limited function of the knee, and effusion persisted. Recovery was successful but was extended beyond original expected time, despite intensive physical therapy. This was thought to be due to the concurrent osteoarthritis.

Extra facts:

*     A feeling of instability and of a knee not moving properly can occur when a torn or shredded piece of a meniscus floats freely between the articulating surfaces of the femur and tibia causing proprioceptor receptors to send incorrect messages.

*     The most favorable outcomes in meniscal tears involve age (less than 35 yrs.), no involvement of the cartilage, and a fully intact rim of the meniscus after repair (only possible with certain tears).

*     The most common sports associated with meniscal tears are basketball, rugby, soccer, football, and hockey where there is quick acceleration and deceleration laterally with the foot in a fixed position.