Knee Examination

Introduction0/7

• Greetings
• Hand wash
• Verify the patient's identity using at least two or three details
• Explanation
• Consent
• Asking if there are any pain
• Asking for dominant footConsider asking which side is the patient's kicking foot if they are a sportsperson

Inspection0/8

• Exposing both legs
• Inspect while standingCheck for general lower leg alignment (valgus or varus deformity), scars or sinuses, swelling in the posterior aspect of the knee (Baker's cyst)
• Gait
  • AntalgicIndicative of pain
  • Short-leg
• Ask the patient to lie supine
  • Comment on muscle wasting and skin changesCheck for swelling in the anterior aspect of the knee, position (valgus/varus/partially flexed/hyperextended), bruising, quadriceps wasting, posterior sag with knee flexed at 90 deg
• Warmth/temperatureUse back of hands and compare sides

Palpations and look for tenderness at 30 degree flexion0/10

• Tibial tuberosity
• Quadriceps tendon
• Patella tendon
• Patella
• Medial and lateral retinaculae
• Medial and lateral joint lines
• Hamstrings tendon
• Gastrocnemius tendon
• Look for baker's cystA Baker's cyst is usually just below the joint line, a semimembranous bursa just above. A popliteal cyst related to the popliteal artery is pulsatile.
• Swipe testTests for an effusion - empty the medial suprapatellar pouch by stroking the fluid in a superior direction then milk the fluid back into the knee from above on the lateral side and watch for reaccumulation of medial fluid

Movements0/7

• Active
  • Flexion
  • Extension
• Passive while feeling for crepitus
  • FlexionNormally the knee will flex such that the calf meets the posterior thigh. A hand should be placed over the patella to feel for PFJ crepitus when passively flexing up the knee and returning it to supine resting position (extension)
  • ExtensionPatient supine: hold both legs by the toes looking for fixed flexion or hyperextension
  • Feeling for crepitus

• Patella apprehension testKnee on pillow in 20-30 deg flexion and gently push the patella laterally; positive if the patient develops apprehension and describes a feeling of impending dislocation
• MCL and LCL ↔ valgus and varus stressApply valgus force to the knee in full extension and then at 30 deg flexion looking for pain, extent of valgus movement and an end point. Repeat with varus stress. There is normally some mediolateral movement at 30 deg but if excessive compared to the normal side suggests collateral ligament instability (injury)
  • Once at full extension
  • Once at 30 degree flexion
• McMurray's TestKnee is flexed and at various stages IR and ER of the tibia is performed. Fingers on joint line: a palpable clunk is consistent with release of a torn meniscus trapped between articular surfaces. Pain alone may suggest meniscal damage BUT may be related to other pathology e.g. medial joint line OA, PFJ abnormality
• Anterior drawer testWith knee in 90 deg flexion and the foot stabilised. Ensure hamstrings are relaxed with index fingers on femoral condyles draw the tibia anteriorly and assess degree of movement and end point compared to the opposite side (ACL)
• Posterior drawer testAs per anterior drawer except grip the tibia firmly and push it posteriorly again assessing for movement and end point quality (PCL)
• Lachman's test at 15 degrees of flexionKnee in 15 deg flexion, draw the tibia forwards feeling for laxity and end point compared to the opposite side (ACL)
• Wash hands