NPTE MSK Basics: Examination and Intervention

Why does the tibia rotate laterally during full knee extension (screw-home mechanism)?

the lateral femoral condyle is flatter, does not extend as far distally, and projects farther posteriorly than the medial femoral condyle. Because the medial femoral condyle extends farther distally, the medial side continues moving after the lateral side has stopped, causing the tibia to rotate laterally (externally) on the femur during the last 20-30° of knee extension. This is the screw-home mechanism, which locks the knee and increases stability in full extension

what is FF tip for the screw home mechanism

TOLL: tibia, open chain goes laterally for locking!

Which type of contraction do the biceps undergo as the shoulder moves from 180° toward 90° of flexion? Stand to Sit?

more flexion to less flexion: eccentric contraction

stand to sit: less flexion now onto more flexion. concentric

if you see slowing down in gravity think of ECCENTRIC!

what are the upward rotators of scapula? what about downward rotation?

go and think of the mnemonic: upper part of traps, serratus anterior, lower part of traps

downward:rhomboids, levator, and pec minor

Active Insufficiency

The inability of a multi-joint muscle to shorten simultaneously at all joints.

Passive Insufficiency

The inability of a multi-joint muscle to lengthen simultaneously at all joints.

what are the steps to think when doing the passive/active insufficiency question

Step 1: Name of the muscle

Step 2: Is it a two joint muscle?

Step 3: End range? Function of the muscle? Step 4: Active (same) or passive (opposite)

here is an example of active/passive insufficiency?

step 1: hamstrings

2: yes

3: knee flexor hip extensors

4: active-knee flexor hip extensors since SAME. they doing their function at two jts but struggle to do so.

passive: opposite to their function; so knee extension and hip flexion

so think passive is where you feel a stretch!

Knee Locking (Open Chain)

Tibia rotates laterally on the femur during full extension.

Knee Unlocking Action

Femur rotates laterally on the tibia (or tibia rotates medially).

Rotator Cuff Repair Post-Op Position (Day 6)

Supine with arm abducted 45° with slight flexion.

Achilles tendon repair: Traditional vs. early weight-bearing?

Traditional: 6 weeks immobilization + non-weight-bearing

Early remobilization: Immediately after surgery or within 1-2 weeks

Phase 1 (0-4/6 weeks) after Achilles tendon repair: Key interventions?

Active ROM of non-immobilized joints

Muscle setting (DF, PF, inversion, eversion) starting at ~2 weeks

Weight shifting in bilateral stance when partial WB is allowed

No dorsiflexion to avoid stretching the repaired tendon

Thompson Test

Special test used to assess for an Achilles tendon rupture.

Femoral Anteversion Presentation

Hip internal rotation, tibial internal torsion, subtalar pronation, and toe-in, squinting patella

Femoral Retroversion Presentation

Hip external rotation, tibial external torsion, subtalar supination, and toe-out, frog eyes patella.

Excessive Scapular Upward Rotation Cause

Weakness of the rhomboid major and minor.

Reduced Hip Extension with Knee Flexion Cause

Passive insufficiency of the rectus femoris.

Weak Grip in Wrist Flexion Cause

Active insufficiency of finger flexors; passive insufficiency of finger extensors.