The Pain Source

Patient Position

• Supine or seated
• Knee flexed to 20-30°

Procedure Steps

• Grab behind the proximal tibia and pull anteriorly (perpendicular to the tibia).
  • Stabilize the femur with one hand (so it doesn’t track forward).
• Perform the same steps on the opposite (unaffected) knee.

Positive Sign / Significance

• Increased anterior translation compared to the other side (or a mushy, soft end-feel) = Anterior cruciate ligament injury

Comments

• When the knee is flexed to 90°, the hamstring tendons and iliotibial band also prevent anterior translation of the tibia in relation to the femur.  Therefore, this Lachman’s test is preferred over the anterior drawer test.

Related Content:

• Ultrasound – Knee Exam Setup
• Ultrasound – Femoral Condyle Cartilage Exam
• Ultrasound – Quadriceps Tendon Exam
• Ultrasound – Iliotibial Band Exam
• Ultrasound – Lateral Collateral Ligament Exam

Patient Position

• Supine (or seated)

Procedure Steps

Supine testing

• Stand to the outside of the patient.
• Drop the leg off the table and flex the knee to 30°.
• Put fingers of proximal hand over the medial joint line.
• Place your hip against the lateral knee and use it as a fulcrum to apply a valgus force at the knee (distal hand at the foot/ankle).
• Compare to the opposite, unaffected side.

Seated testing

• Flex the involved knee to 30°
• Support the medial ankle with one hand
• Apply a valgus force (lateral to medial) at the knee – check for pain
• Put your fingers along the medial joint line while applying the force to feel for gapping or a soft end-feel
• Compare to the opposite, unaffected side.

Positive Sign / Significance

• Significantly increased medial joint space gapping (compared to other side) = Medial collateral ligament tear (grade 3 complete tear)
• Increased medial knee pain with valgus pressure = MCL sprain
  

Related Content:

• Ultrasound – Medial Collateral Ligament Exam
• Acromioclavicular Joint Injection – Technique and Tips
• Pes Anserine Bursitis

Patient Position

• Supine (or seated)

Procedure Steps

Supine testing

• Drop the leg off the table and flex the knee to 30°.
• Put fingers over the lateral joint line.
• Grab the ankle/foot and apply a varus stress to the knee (using the medial knee against the outside of the table as a fulcrum and pushing the ankle lateral to medial).
• Compare to the opposite, unaffected side.

Seated testing

• Grasp the lateral ankle on the involved side of the body
• Flex the knee to 20-30°
• With the other hand, apply a medial-to-lateral varus force against the medial knee

Positive Sign / Significance

• Significantly increased lateral joint space gapping = Lateral collateral ligament injury (grade 3 complete tear)
• Pain over the lateral knee = Lateral collateral ligament sprain

Related Content:

• Ultrasound – Lateral Collateral Ligament Exam