Kinesiology of the Hip:

By Brent Brookbush MS, PES, CES, CSCS, ACSM H/FS

Hip Extension

• Prime Mover: Gluteus maximus
• Synergists: Biceps femoris (long head) , semitendinosus, semimembranosus , posterior head of adductor magnus
• Antagonists: Psoas , iliacus , tensor fascia latae  (TFL), rectus femoris , anterior adductors (especially pectineus) , sartorius
• Neutralizers: Gluteus minimus and anterior fibers of gluteus medius neutralize external rotation force of gluteus maximus
• Stabilizers: Deep rotators of hip
• Fixators: Intrinsic stabilization subsystem , rectus abdominis , internal and external obliques , quadratus lumborum , erector spinae

Hip Flexion

• Prime Mover: Psoas
• Synergists: Iliacus , tensor fascia latae , rectus femoris , anterior adductors (especially pectineus) , sartorius
• Antagonists: Gluteus maximus , biceps femoris (long head) , semitendinosus, semimembranosus , posterior head of adductor magnus
• Neutralizers: The psoas and iliacus must work in concert with the TFL and anterior adductors to prevent internal and external rotation and/or abduction and adduction
• Stabilizers: Deep rotators of hip
• Fixators: Intrinsic stabilization subsystem , rectus abdominis , internal and external obliques , quadratus lumborum , erector spinae

Hip Internal Rotation

• Prime Mover: Gluteus minimus
• Synergists: Anterior fibers of gluteus medius , tensor fascia latae , semitendinosus, semimembranosus , anterior adductors
• Antagonists – Gluteus maximus , posterior fibers of gluteus medius , biceps femoris (long head) , posterior head of adductor magnus , deep rotators of hip , sartorius
• Neutralizers – Gluteus maximus , gluteus medius , and gluteus minimus prevent excessive adduction and flexion, especially during closed chain activities like an axe chop.
• Stabilizers: Deep rotators of hip
• Fixators: Intrinsic stabilization subsystem , rectus abdominis , internal and external obliques , quadratus lumborum , erector spinae

Hip External Rotation

• Prime Mover: Piriformis
• Synergists: Deep rotators of hip , gluteus maximus , posterior fibers of gluteus medius , biceps femoris (long head) , posterior head of adductor magnu s, sartorius
• Antagonists: Anterior fibers of gluteus medius , gluteus minimus , tensor fascia latae , semitendinosus, semimembranosus , anterior adductors
• Neutralizers: Hip flexors and anterior adductors may reduce propensity of external rotators to extend and abduct the hip
• Stabilizers: Deep rotators of hip , gluteus medius , gluteus minimus
• Fixators: Intrinsic stabilization subsystem , rectus abdominis , internal and external obliques , quadratus lumborum , erector spinae

Hip Abduction

• Prime Mover: Gluteus medius
• Synergists: Gluteus maximus (superior fibers) , gluteus minimus , tensor fascia latae , sartorius , vastus lateralis via fascial slips
• Antagonists: Adductor magnus, pectineus, adductor brevis, adductor longus, gracilis , gluteus maximus (inferior fibers) , quadratus femoris
• Neutralizers: The abductors of the thigh also contribute to rotation. A careful balance of strength and flexibility between internal and external rotators ensures optimal muscular synergies. The psoas , rectus femoris , pectineus , biceps femoris , semitendinosus, and semimembranosus prevent ancillary flexion and extension of the hip.
• Stabilizers: Deep rotators of hip
• Fixators: Intrinsic stabilization subsystem , rectus abdominis , internal and external obliques , quadratus lumborum , erector spinae

Hip Adduction

• Prime Mover: Adductors
• Synergists: Gluteus maximus (inferior fibers) , quadratus femoris , semitendinosus, semimembranosus
• Antagonists: Gluteus maximus (superior fibers) , gluteus medius , gluteus minimus , tensor fascia latae , sartorius , vastus lateralis via fascial slips
• Neutralizers: The adductors of the thigh also contribute to rotation. A careful balance of strength and flexibility between internal and external rotators ensures optimal muscular synergies. The psoas , rectus femoris , pectineus , biceps femoris , semitendinosus, and semimembranosus prevent ancillary flexion and extension of the hip.
• Stabilizers: Deep rotators of hip
• Fixators: Intrinsic stabilization subsystem , rectus abdominis , internal and external obliques , quadratus lumborum , erector spinae

Hip Horizontal Abduction

• Prime Mover: Piriformis
• Synergists: Deep rotators of hip , gluteus medius , gluteus minimus , tensor fascia latae , gluteus maximus
• Antagonists: Pectineus, adductor brevis, adductor longus, adductor magnus (both heads), gracilis
• Neutralizers: Hamstrings and hip flexors neutralize ancillary motion in the sagittal plane, TFL neutralizes external rotation force created by the piriformis and deep rotators of the hip .
• Stabilizers: Deep rotators of hip , gluteus medius , gluteus minimus , pectineus
• Fixators: Intrinsic stabilization subsystem , rectus abdominis , internal and external obliques , quadratus lumborum , erector spinae

Hip Horizontal Adduction

• Prime Mover: Anterior adductors
• Antagonists: Deep rotators of hip , gluteus medius , gluteus minimus , tensor fascia latae , gluteus maximus
• Synergists: Posterior head of adductor magnus
• Neutralizers: Hamstrings and hip flexors neutralize ancillary motion in the sagittal plane, and the posterior head of the adductor magnus neutralizes internal rotation force created by the anterior adductors.
• Stabilizers: Deep rotators of hip , gluteus medius , gluteus minimus , pectineus
• Fixators: Intrinsic stabilization subsystem , rectus abdominis , internal and external obliques , quadratus lumborum , erector spinae

© 2011 Brent Brookbush

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