Case Study

Question 1

What types of equipment would have been used in the CS?

Answer 1

• reflective markers on bony landmarks
• 2D vicon motus analysis (1 camera (placed perpendicular to plane of motion), tripod, calibration frame)
• Surface + intramuscular (fine wire) EMG
• participant in minimal clothing

Question 2

Describe the protocol used for the CS?

Answer 2

• minimal clothing
• attach reflective markers to bony landmarks
• set up camera on tripod (contrasting background, perpendicular to plane of motion, ensure full body is in shot)
• needle inject fine wire electrodes
• attach surface electrodes
• get patient to stand in natural position (calibration video)
• calibrate systems
• get video data of natural running (entire gait cycle)

Question 3

Explain why there is differences in Q angle between men and women?

Answer 3

• increased pelvis/broader
• increased quadricep angle (Q angle)
• increased valgus orientation of hip and quad extensor mechanism
• leads to increased lateral pull of the patella away from the midline
• causes cartilage to soften and wear away (subchondral bone) over time causing rubbing of the patella bone on other bones
• inflammed and pain

Question 4

List 3 muscles/ cartilage that can be affected by overloading due to repeated motion in the malalignment?

Answer 4

• patella retinaculum (tendon medial)
• retropatellar articular cartilage
• subchondral bone (shock absorbing cartilage)

Question 5

List things that can cause anterior knee pain?

Answer 5

• increased Q angle (pressure onto the lateral facet of the patella)
• pronated foot/ tibial torsion
• abnormal alignment of the knee extensor mechanism
• direct trauma
• overuse
• increased femoral anteversion
• decreased quad, hamstring, IT band flexibility
• quadricep weakness
• poor pelvic muscular control

Question 6

Name the values for peak hip adduction in degrees (normal vs CS)?

Answer 6

CS= 20 degrees
Normal= 14.3 degrees
(Nakagawa, 2013)
-increase in hip adduction for PFP

Question 7

Name the values for peak hip internal rotation in degrees (normal vs CS)?

Answer 7

CS= 8 degrees
Normal= 3.37 degrees
(Pollard, 2004)
-increased hip internal rotation for PFP

Question 8

Name values for contra-lateral pelvic drop in degrees (normal vs CS)?

Answer 8

CS=8 degrees (more variance during entire swing phase)
Normal= 1 degrees (less variance between entire swing phase)
Noehren et al (2012)

Question 9

Name values of main hip adductor (%MVC) (normal vs CS)?

Answer 9

CS= 75%
normal= 87%
Lovell (2012)

Question 10

Name values of main hip adductor time point prior to foot contact (normal vs CS)?

Answer 10

CS=20 ms
normal=30ms
Lovell (2012)

Question 11

Name values of activation duration (normal vs CS)?

Answer 11

CS=130s
normal= 160s
Lovell (2012)

Question 12

Name all 4 quadricep muscles?

Answer 12

Rectus femoris (middle)
Vastus medialis (medial)
Vastus lateralis (lateral)
Vastus intermediairs (deep to RF)

Question 13

Name hip adductor muscles?

Answer 13

Adductor Longus
Adductor Magnus
Gracilis
Sartorius (long s shape-attaches to medial patella)

Question 14

Name other hip muscles?

Answer 14

Iliopsoas
Tensor face later
IT band

Question 15

Suggest basic treatment strategies?

Answer 15

• Advice on normal posture
• train/strengthen quads/ hip muscles
• flexibility exercises for quads, hamstrings and ITband

Question 16

An increase in 10 degrees of Q angle increases what by 45 %?

Answer 16

lateral contact pressure on patellofemoral joint