KNEE EXAM

Inspection

Gait

  • Stance Phase (60% of gait cycle): heel strike → mid-stance → toe-off
  • Swing Phase (40% of gait cycle): toe-off → mid-swing → heel strike
  • Quality of Gait: Smoothness of movement (legs, arm swing, pelvic tilt), symmetry, normal stride length, ability to turn quickly
  • Abnormal Gaits to Assess for: antalgic gait (shortened stance phase on affected side, typically indicates pain with weight-bearing)

SEADS

S= swellingInspect all sides, including Popliteal Fossa for Baker’s Cysts (only seen in large effusions)
E = erythema
A = atrophyInspect calves; quads; hamstrings
D = deformityo Genu Varum (bow-legged)
o Genu Valgum (knock-kneed)
o Genu Recurvatum (hyperextension)
o Genu Procurvatum (flexion deformity, always abnormal)
S = skin changesNote any rash, surgical scars, psoriasis, rheumatoid nodules, gouty tophi 

Palpation

  • Commenting on: TESTCA – Tenderness, Effusions, Swelling, Temperature, Crepitus, & Atrophy
  • Ottawa Knee Rule: palpate patella and fibular head for tenderness.
  • With Knee Extended:
    • Temperature: Sweep with back of hand – Patella should be cooler than thigh above and tibia below.
    • Patella Palpation: Feel undersides by tilting patella to each side, feel with fingers or thumb
    • Palpating Anteriorly, From Superior to Inferior: Quadriceps most superior→ Suprapatellar Tendon → Patellar Ligament → Tibial Tuberosity most inferior
    • Palpating Popliteal Fossa Posteriorly: Check popliteal pulse and for swelling
    • Palpating 4 Bursae:
      • Pre-Patellar Bursa (in front of patella)
      • Superficial Infra-Patellar Bursa (inferior to patella, overlying patellar ligament and under skin)
      • Deep Infra-Patellar Bursa (behind patellar ligament)
      • Anserine Bursa (anteromedial aspect of knee, near medial tibial plateau, deep to sartorius, gracilis and semitendinosus tendons)
  • With Knee Flexed to 90°:
    • Palpate Joint Line: Medial & Lateral Joint Line; Medial Collateral Ligament (MCL); Medial & Lateral Tibial Plateaus; Femoral Condyles
  • Adopt Figure of 4 Position (Heel resting on contralateral knee):
    • Palpate Lateral Collateral Ligament (LCL), felt as cord on lateral knee aspect. Can feel hard as bone.
  • Palpation for Effusion:
    • Fluid Wave Test or Bulge Sign (useful for smaller effusions): sweep your hand up the medial aspect of the knee to empty the medial fossa. Then sweep down the lateral aspect. As you sweep down the lateral aspect, look for a bulge forming in the medial fossa. A bulge forming in the medial fossa indicates an effusion (may be false negative in larger effusions)
    • Fluid Ballottement Test: with leg extended, grasp knee just above the patella with 1 hand. With other hand, grasp the medial and lateral parapatellar fossae. With hand just above patella, apply and release pressure, while feeling for ballotable fluid in other hand. If ballotable fluid, this indicates an effusion.
    • Patellar Tap (useful for moderate-large effusions): Apply pressure with one hand just above the patella and sweep down until you reach the upper pole of the patella. This pushes fluid into the suprapatellar pouch behind patella. Keep pressure applied. With other hand, use 1-2 fingers to push the patella down, and assess whether it taps the femur and bounces back up. If patella taps the femur, then bounces back up, this indicates an effusion (may be false negative in smaller effusions)

Range of Motion (RoM)

  • Approach: perform Active ROM, and then Passive ROM if Active ROM is limited
    • Flexion (135°): assess patellar crepitus during flexion-extension by placing 1 hand on patella
    • Extension (180° → 10° hyper-extension past 180° is abnormal hypermobility)
    • Internal Rotation (30°): flex knee to 90°, point toes in
    • External Rotation (20°): flex knee to 90°, point toes out
    • Patellar Movement: push medially and laterally on patella; assess for hypermobility, pain or apprehension from dislocation.
      • Patellar Compression test: With clinician hand just proximal to patella, press down and push patella distally, then ask patient to contract quadriceps – pain may indicate pain in patellofemoral compartment e.g. in patellofemoral osteoarthritis.

Power

  • Approach: resisted isometric testing i.e. patient resists force applied by clinician
    • Sitting Approach: with knee flexed to 45-90° over side of bed.
    • Knee Extension: examiner braces knee & pushes leg towards bed, patient kicks out
    • Knee Flexion: examiner braces knee & pushes leg away from bed, patient pushes in
  • Reporting: for each muscle group tested, assess per the Medical Research Council Power Grading (scale of 0/5 to 5/5)

Special Tests

  • Anterior/Posterior Drawer tests:
    • Patient supine, knee at 90° flexion. Stabilize tibia, grasping proximal tibia with thumbs on either side of joint line. Look for excess displacement of tibia.
    • Anterior Drawer: apply anterior force to pull tibia forward.
    • Posterior Drawer: apply posterior force to push tibia backward.
  • Lachman test:
    • Patient supine, knee at 30° flexion. Stabilize femur with one hand and grasp upper tibia with other hand.
    • Try to pull tibia forward. Assess for excess anterior movement of the tibia (or no discrete end point).
  • MCL/LCL Stress tests:
    • Patient supine, knee at 30° flexion. Stabilize knee posteriorly with one hand. Stabilize lower leg with other hand. Look for ↑ laxity and pain at MCL/LCL.
    • MCL stress test: apply valgus (lateral) force to lower leg, knee stabilized.
    • LCL stress test: apply a varus (medial) force to lower leg, knee stabilized.
  • McMurray’s test:
    • Patient supine. Clinician flexes knee fully and places one hand over knee and other hand under the foot. If pain is elicited, or a palpable or audible click occurs, this indicates a meniscal tear.
    • For a medial meniscus tear: externally rotate the foot, and apply a varus (medial) force on lower leg while extending knee.
    • For a lateral meniscus tear: internally rotate the foot and apply a valgus (lateral) force on lower leg while extending the knee.
  • Apley’s compression test:
    • Patient supine, knee flexed to 90o, clinician stabilizes femur with one hand, grasps heel with other hand. If pain is elicited, or a popping/clicking noise occurs, this indicates a tear of the respective meniscus.
    • Grasp patient’s heel and apply downward pressure through heel while rotating lower leg internally and externally. Apply a varus force/tilt (medial) for medial meniscus, and a valgus force/tilt (lateral) for lateral meniscus.