Skeletal joint actions
Spine Upper limbs Lower limbs
Extension Scapular upward rotation and
elevation, shoulder flexion,
elbow extension, forearm
pronation, wrist dorsiflex-
ion, hand and finger exten-
sion
Hip extension and adduction,
knee flexion, ankle plantar
flexion
Muscular joint actions
Spine
Concentric contraction Eccentric contraction
To lift head away from floor:
Rectus capitis posterior, obliquus capitis
superior
To maximize extension of spine:
Spinal extensors
To keep from hyperextending lumbar spine:
Psoas minor, abdominals
Upper limbs
Concentric contraction
To upwardly rotate and elevate scapula:
Serratus anterior
To stabilize and protect shoulder joint:
Rotator cuff, deltoid
To flex shoulder:
Biceps brachii, anterior deltoid
To extend elbow:
Triceps brachii
To pronate forearm:
Pronator quadratus and teres
To maintain integrity of hand:
Intrinsic muscles of wrist and hand
Lower limbs
Concentric contraction
To extend hip:
Hamstrings, gluteus maximus
To extend, adduct, and internally rotate hip:
Adductor magnus, gracilis
To extend knee:
Articularis genu, vastii
(continued)