Physical examination of acute ankle and knee injuries

View Dr Michael Ellis conducting examination and physical tests for meniscal tears of the knee.

This video (3:03 minutes) demonstrates four physical tests used in the diagnosis of a meniscal tear

McMurray test

1. Patient lies supine. Flex the knee maximally.
   
2. Hold the foot, grasping the heel with one hand.
   
3. Then hold the knee joint with the other hand, placing your fingers along the medial joint line (to assess medial meniscus) and lateral joint line (to assess lateral meniscus).
   
4. For the medial meniscus, rotate the tibia laterally together with a valgus force and at the same time extend the knee. For the lateral meniscus, rotate the tibia medially together with a varus force and at the same time extend the knee.
   

Positive test result: when the patient feels pain and there is an audible or palpable ‘snap’, ‘click’ or ‘thud’ during extension movement.

Starts at 0:07

Thessaly test

1. Hold patient’s outstretched hands.
   
2. The patient stands on one leg, the injured leg, with the knee flexed to 20° and foot flat on the ground.
   
3. The patient then rotates their knee and body, medially and laterally, three times, keeping the knee at 20° flexion.
   

Positive test result: when the patient experiences medial or lateral joint line pain.

Starts at 1:08

Joint line tenderness test

1. Patient lies supine with the injured knee flexed to 90°.
   
2. Palpate medially and laterally along the joint line between the femur and tibial condyles.
   

Positive test result: when the patient experiences pain during the palpation. Pain along the medial joint line indicates medial meniscus damage, and along lateral joint line indicates lateral meniscus damage.

Starts at 1:46

Apley grind test

1. Patient lies prone with the injured knee flexed to 90°.
   
2. Grasp the foot with both hands, apply downwards compression pressure and at the same time rotate the tibia medially, and then laterally.
   

Positive test result: when there is pain and/or clicking.

Starts at 2:22

This video ( 2:20 minutes) demonstrates three physical tests used in the diagnosis of an ACL tear.

Lachman test

1. Patient lies supine with injured leg at the examiner’s side, and the knee joint flexed 20° to 30°.
   
2. Hold the thigh still with one hand.
   
3. Pull the tibia forward in an anterior translation movement.
   
4. Positive test result: increased anterior translation movement and a soft endpoint compared with the uninjured knee.
   

Note: There can be a false-negative result if the patient’s hamstrings are not relaxed.

Starts at 0:08

Anterior drawer test

1. Patient lies supine and the injured knee is flexed to 90°, foot flat on the table and in neutral rotation.
   
2. Sit on the dorsum of the foot.
   
3. Grasp the tibia below the joint line of the knee, placing thumbs along the joint line on either side of the patellar tendon. Ensure hamstring tendons are relaxed by feeling the tendons.
   
4. Pull the tibia forward (anterior translation movement) and feel for laxity and quality of endpoint.
   

Positive test result: increased anterior translation movement with a soft endpoint compared with the uninjured knee.

Starts at 0:50

Pivot shift test

1. Patient lies supine with the injured knee medially rotated and fully extended. In a patient with an ACL tear, the femoral condyles will be subluxated.
   
2. Apply a valgus force.
   
3. Then flex the knee observing for an audible or palpable ‘clunk’ of reduction.
   

Positive test result: audible or palpable ‘clunk’, usually occurring at 30° flexion.

Starts at 1:40

This video (1:12 minutes) demonstrates two physical tests used in the diagnosis of an ankle sprain (lateral ligament).

Anterior drawer test

1. Patient lies supine. Flex the knee joint slightly and hold the injured ankle in 10°to 15° plantar flexion.
   
2. Move the rear foot upwards (anterior translation movement).
   
3. Hold the lower leg still throughout.
   

Positive test result: excessive anterior translation movement compared with the uninjured ankle.

Starts at 0:08

Talar tilt test

1. Patient lies supine. Ensure the injured ankle is in the neutral position while holding the lower leg still.
   
2. Invert the talus and calcaneus.
   

Positive test result: increased inversion movement compared with the uninjured ankle.

Starts at 0:39

This video (2:09 minutes) demonstrates the Ottawa Rules used to determine whether or not to refer a patient for X-ray series to diagnose fractures of the ankle (and foot) and knee.

Ottawa Ankle Rules

An ankle X-ray series is only required if there is any pain in the malleolar zone and any of these findings:

• bone tenderness at posterior edge (distal 6 cm) or tip of medial malleolus OR
  
• bone tenderness at posterior edge (distal 6 cm) or tip of lateral malleolus OR
  
• inability to bear weight both immediately and in the emergency department for four steps.
  

A foot X-ray series is only required if there is any pain in the mid-foot zone and any of these findings:

• bone tenderness at the base of the fifth metatarsal OR
  
• bone tenderness at the navicular OR
  
• inability to bear weight both immediately and in the emergency department for four steps.
  

Starts at 0:08

Ottawa Knee Rules

A knee X-ray series is only required for patients with knee injury if any of these findings are present:

• age 55 or older OR
  
• isolated tenderness of the patella (no bone tenderness of the knee other than the patella) OR
  
• tenderness of the head of the fibula OR
  
• inability to flex to 90° OR
  
• inability to bear weight both immediately and in the emergency department for four steps (unable to transfer weight twice onto each lower limb regardless of limping).
  

Starts at 1:17

All the instructions in the videos are evidence based. However, there is variability in the medical literature regarding instructions on how to do the physical tests in particular. After an extensive review of this variability, the physical test instructions included in the videos are regarded as best practice.

Examiner

Dr Michael Ellis, MBBS (SYD), MMed (Musculoskeletal), FRACGP Dip RACOG