An odds ratio is defined as a measure of association between an exposure and an outcome, comparing the odds of an outcome occurring in the presence of an exposure versus with no exposure. – Higher diagnostic odds ratios greater than one indicate better test performance. A likelihood ratio close to 1 indicates that the test is of little practical significance. A likelihood ratio less than 1 indicates that the test is associated with the absence of the disease. – Likelihood ratio greater than 1 means the test is associated with the presence of the disease. * Reported value did not distinguish between medial and lateral menisci All other Thessaly test values are at 20° knee flexion. ^ Results for the Thessaly test at 5° knee flexion. The Thessaly test at 20° knee flexion (left), and on external rotation at 20° knee flexion (right). Thessaly test video demonstration.įigure 4. The test can be repeated with the knee at 5° of flexion, as well as on the opposite leg for comparison. The test is positive if there is reproducible pain in the knee upon rotation (Figure 4). 2 The patient then flexes their affected knee to 20°, internally and externally rotating their body 3 times, using their knee as the pivot point. With the patient standing facing you, hold the patient’s outstretched hands while they bear weight on their affected leg only. Pain on palpation of the knee joint line (between the femur and the tibia) is a positive test. Testing of the medial meniscus using the McMurray test. McMurray test video demonstrationįigure 2. When assessing the medial meniscus, the stress applied is a valgus (abduction) force with passive external rotation and extension of the knee (Figure 2). 2 A popping or clicking sound is a positive finding for a lateral meniscus injury. Starting with the patient’s knee and hip fully flexed, apply a varus force (adduction) while passively internally rotating the foot and extending the knee simultaneously. There are 2 components to the McMurray test, examining both the medial and lateral meniscus. 6 Commonly Used Tests for Detecting Meniscal Injury 5 Superior view of the right tibia (right) note location of the menisci. 2–4 We will compare the evidence for these tests below.įigure 1.
Many tests exist to help diagnose meniscal injuries, including the McMurray test, the Thessaly test, and joint line tenderness. 1 Common symptoms include joint line tenderness, a clicking noise, knee locking, and recurrent delayed joint effusions (most commonly with associated cruciate and/or patellar subluxation or dislocation). Meniscal injuries often occur following a twisting injury to the knee, usually with the foot planted on the floor. What is the “Thessaly Test” and has it been proven useful in the detection of meniscal injuries? Meniscal Injuries Your staff raises an eyebrow and asks you what this so-called “Thessaly test” is, and asks whether it is actually useful in detecting meniscal injury. You report to your attending staff that you suspect the patient has a meniscal tear based on the finding of a positive Thessaly test, and would like to send her for an outpatient MRI. Tests for anterior collateral ligament (ACL), posterior collateral ligament (PCL), medial and lateral collateral ligament laxity and joint effusion are all negative. The knee is not edematous, warm, or erythematous, and there is no evidence of deformity or bruising.
On exam she can bear minimal weight on the affected leg and has pain on knee flexion as well as on palpation of the medial aspect of the knee. She has no past medical history, her vitals are stable and she is afebrile. She has no recent trauma, is not sexually active and her review of systems is otherwise normal. On history, her right knee has been sore for the past 2 days, with swelling and worsening pain since last night, and she is now unable to weight bear on her right leg. Your next patient is a 27 year old female with a chief complaint of “lower extremity injury”. You are working a shift in the ambulatory zone of your emergency department.