Kinesiology of the Knee:
By Brent Brookbush MS, PES, CES, CSCS, ACSM H/FS
Knee Extension:
- Prime Mover: Quadriceps - vastus lateralis, vastus medialis, vastus intermedius , rectus femoris
- Synergists: There are no true synergists of knee extension. However, the gluteus maximus and soleus could be viewed as synergists to knee extension during closed chain mechanics.
- Antagonists: Biceps Femoris , semimembranosus, semitendinosus , popliteus , gastrocnemius , gracilis , sartorius
- Neutralizers: Careful balance between medial and lateral stabilizers of the knee must be maintained to prevent excessive internal or external rotation of the tibia. More complex relationships between synergistic pairs exist - for example, the short head of the biceps femoris and vastus medialis obliquus are functional antagonists.
- Stabilizers:
- Medial stabilizers - Pes Anserinus group, semimembranosus , medial gastrocnemius , and vastus medialis obliquus , popliteus
- Lateral Stabilizers - Gluteus maximus , TFL , and vastus lateralis via the iliotibial band, biceps femoris , and lateral gastrocnemius, plantaris
- Popliteus , Articular muscle of knee
- Fixators: All muscles of the ankle, hip, and LPHC. Especially the intrinsic stabilization subsystem , the glute complex, and invertors of the ankle.
Knee Flexion:
- Prime Mover: Biceps femoris , semimembranosus, semitendinosus
- Synergists: popliteus , gastrocnemius , gracilis , sartorius
- Antagonists: Quadriceps - vastus lateralis, vastus medialis, vastus intermedius , rectus femoris
- Neutralizers: Careful balance between medial and lateral stabilizers of the knee must be maintained to prevent excessive internal or external rotation of the tibia. More complex relationships between synergistic pairs exist - for example, the short head of the biceps femoris and vastus medialis obliquus are functional antagonists.
- Stabilizers:
- Medial stabilizers - Pes Anserinus group, medial gastrocnemius , and vastus medialis obliquus
- Lateral Stabilizers - Gluteus maximus , TFL , and vastus lateralis via the iliotibial band, lateral gastrocnemius, plantaris
- Popliteus , articular muscle of knee
- Fixators: All muscles of the ankle, hip, and LPHC. Especially the intrinsic stabilization subsystem , the glute complex, and invertors of the ankle.