MSK - Knee

Question 1

“What signs can be found on general inspection?”

Answer 1

• Body Habitus (Significant RF for Joint Pathology)
• Scars
• Wasting of Muscles
• Peripheral Paraphenalia of Disease (Walking Aids, Prescriptions)

Question 2

“What signs can be found on closer inspection of the knee?”

Answer 2

Anterior

• Scars
• Bruising
• Swelling
• Quadriceps Wasting
• Valgus/Varus deformity of the knees
• Patellar Position
• Psoratic Plaques

Lateral

• Extension or Fixed Flexion Deformities

Posterior

• Scars
• Muscle Wasting
• Popliteal Swelling

Question 3

“Describe the 6 steps in the normal Gait Cycle?”

Answer 3

1. Heel-strike:initial contact of the heel with the floor.
2. Foot flat:weight is transferred onto this leg.
3. Mid-stance:the weight is aligned and balanced on this leg.
4. Heel-off:the heel lifts off the floor as the foot rises but the toes remain in contact with the floor.
5. Toe-off:as the foot continues to rise the toes lift off the floor.
6. Swing:the foot swings forward and comes back into contact with the floor with a heel strike (and the gait cycle repeats).

Question 4

“Describe some abnormal Gaits?”

Answer 4

• Trendelenburg’s Gait→ Unilateral Hip Abductor Weakness→ Typically caused by Superior Gluteal Nerve Lesion or L5 Radiculopathy→ As you lift one leg off the ground to walk, the contralateral hip abductor should work. In Trendelenburg’s Gait it doesn’t, therefore organically that hip should drop to the floor. The compensation of the body, is to throw the whole trunk over to the other side to compensate.→ MAIN POINT - The Trunk ‘lurches’ in the same direction as the lesion.→ Bilaterally - Wadding Gait (as below)

Neuro

Upper Motor Neurone Disorder

• Hemiparetic Gait
  
  • Typically seen in UMNL i.e. Post Stroke
  • One leg firmly extended and swinging round in an arc
• Spastic Paraparesis
  
  • Similar to Hemiparetic Gait but Bilateral
  • Both legs stiff and ‘scissoring’

Lower Motor Neurone Disorder (Proximal Myopathy)

• Waddling Gait
  
  • Weakness in the proximal muscles, patient cannot raise hip
  • Trendelenburg Sign
  • Gower’s Sign - Difficult to stand from kneeling/sitting

Lower Motor Neurone Disorder (Peripheral Motor Neuropathy)

• High Stepping Gait
  
  • Typically caused by LMN disorder
  • Weakness in Ankle Dorsiflexion (i.e. foot drop), therefore gait is to avoid foot from dragging

Lower Motor Neurone Disorder (Peripheral Sensory Neuropathy)

• Ataxic, Stamping Gait
  
  • Pt cant feel feet on ground, therefore has an ataxic i.e. broad based gait, and stamps

Cerebellar Disorders
- Ataxic, Broad Based Gait

Misc.

• Parkinsonian Gait
  
  • Small, Shuffling Steps - Stooped Posture - Reduced Arm Swing
• Ataxic-Parkinsonism
  
  • Both Boad Based and Small Steps
  • Seen in older people, commonly due to small vessel cerebrovascular disease.

Question 5

“Describe the process of a Patellar Tap?”

Answer 5

• Empty the Suprapatellar Pouch by sliding your hand down the thigh
• Push the Patella, if you feel a tap as it collides with the femur
• Test positive for an effusion

Question 6

“Describe the process of the Swipe Test?”

Answer 6

• Empty the Suprapatellar Pouch
• Stroke the medial side of the knee towards the body, to empty any fluid
• Stroke the lateral side of the knee away from the body
• If the medial side swells or ripples, positive for effusion .

Question 7

“Describe some causes of pathology at the Popliteal Fossa?”

Answer 7

• Swelling = Baker’s Cyst

- Mass = Popliteal Aneurysm

Question 8

“Describe some tests to determine the patency of the Cruciate Ligaments?”

Answer 8

• There are two Cruciate Ligaments. ACL & PCL. The function of the ACL is to prevent ANTERIOR tibial subluxation. The function of the PCL is to prevent POSTERIOR tibial subluxation
• Posterior Sag Sign
  
  • At 90 degrees of Flexion, inspect the lateral aspect of the knee to ensure the Femur and Tibia are in line
• Anterior Drawer Test
  
  • At 90 degrees of Flexion, Hold the tibia like a baseball bat, thumbs at tibial tuberosity
  • Pull the tibia anteriorly
• Posterior Drawer Test
  
  • At 90 degrees of Flexion, Hold the tibia like a baseball bat, thumbs at tibial tuberosity
  • Push the tibia posteriorly
• Lachman’s Test (only for ACL)
  
  • At 30 degrees of Flexion, place your dominant hand over the tibia with thumb at tibial tuberosity. Non dominant hand stabilising at Femur
  • Pull the tibia anteriorly

Question 9

“Describe some tests to determine the patency of the Collateral Ligaments?”

Answer 9

• There are two collateral ligaments of the knee. MCL, resists valgus forces i.e. prevents the medial movement of the knee. PCL, resists varus forces i.e. prevents the lateral movement of the knee.
• Medial Collateral Assessment
  
  • Cushion the ankle between elbow and side
  • Support the Calf with one hand
  • Place the other on the lateral aspect of the femur and push inwards
• Lateral Collateral Assessment
  
  • Cushion the ankle between elbow and side
  • Support the Calf with one hand
  • Place the other on the medial aspect of the femur and push outwards

Question 10

“Describe a test used to determine the patency of the Menisci?”

Answer 10

McMurray’s Test.