Muscles of the Pelvis, Leg and Foot Lab 21 Muscles of the Pelvis, Leg and Foot
Muscles to know psoas major iliacus gluteus maximus gluteus medius sartorius quadriceps femoris (4) gracilus adductor longus biceps femoris semitendinosis semimembranosus tibialis anterior ext hallucis longus ext digitorum longus fibularis (peroneus) longus gastrocnemius soleus flexor hallucis longus flexor digitorum longus
Muscles of the Pelvis and Lower Limbs Pelvic girdle is tightly bound to axial skeleton: permits little movement has few muscles
Muscles that Position the Lower Limbs Muscles that move the thigh Muscles that move the leg Muscles that move the foot and toes
Generally… Muscles that are lateral are abductors Muscles that are medial are adductors flexors are on inner surface of joint extensors are on outer surface of joint Note: in legs and feet, look at each joint individually (cf. arms)
Muscles that Move the Thigh Gluteal muscles Lateral rotators Adductors Iliopsoas group
Muscles of hip and thigh psoas major iliacus gluteus maximus gluteus medius adductor longus
Gluteal Muscles (1 of 2) Cover lateral surfaces of ilia Gluteus maximus: largest, most posterior gluteal muscle produces extension and lateral rotation at hip Originates on illiac crest, etc., inserts on illiotibial tract and femur
Gluteal Muscles (2 of 2) Gluteus medius and [gluteus minimus]: originate anterior to gluteus maximus insert on trochanter of femur
Muscles that Move the Thigh Figure 11–19a, b
Muscles that Move the Thigh Figure 11–19c, d
Adductors Adductor longus: Gracilis (UPPER LEG): hip flexion and adduction Gracilis (UPPER LEG):
Iliopsoas group 2 hip flexors insert on the same tendon: psoas major originates on lumbar vetebrae, inserts on femur iliacus originates on illium/fossa
Summary: Muscles that Move the Thigh Table 11–16 (1 of 2)
Summary: Muscles that Move the Thigh Table 11–16 (2 of 2)
Muscles that Move the Leg Flexors of the knee: originate on the pelvic girdle generally: hamstrings Extensors of the knee: originate on the femoral surface insert on the patella generally: quads
Flexors of the Knee Biceps femoris Semimembranosus Semitendinosus Sartorius: originates superior to the acetabulum long, ribbon-like muscle traverses the quads and wraps around to the back of the knee
Hamstrings Made up of: All are knee flexors biceps femoris (long and short heads) semimembranosus semitendinosus All are knee flexors
Muscles that Move the Leg Figure 11–20a
Extensors of the Knee 4 muscles of the quadriceps femoris: 3 vastus muscles: vastus lateralis vastus medialis vastus intermedius rectus femoris muscle
Muscles that Move the Leg Figure 11–20b, c
Summary: Muscles that Move the Leg Table 11–17 (1 of 2)
Summary: Muscles that Move the Leg Table 11–17 (2 of 2)
Muscles that Move the Foot and Toes Extrinsic muscles that move the foot and toes include: muscles that produce extension at the ankle (Plantar flexion) muscles that produce flexion at the ankle muscles that produce extension at the toes muscles that produce flexion at the toes
Muscles that Produce Extension at the Ankle (Plantar flexion) Calf muscles Large posterior calf muscles, both insert on Achilles): Gastrocnemius Soleus Fibularis longus
Muscles that Move the Foot and Toes Figure 11–21a, b
Muscles that Move the Foot and Toes Figure 11–21c, d
The Achilles Tendon The calcaneal tendon (Achilles tendon): shared by the gastrocnemius and soleus
Muscles that Produce Flexion at the Ankle Tibialis anterior: opposes the gastrocnemius
Muscles that Move the Foot and Toes Figure 11–21a, b
Muscles that Move the Foot and Toes Figure 11–21c, d
Muscles that Produce Extension at the Toes Extensor digitorum longus Extensor hallucis longus Toe extensors are on top of foot Note: there are no muscles in toes themselves (only tendons)
The Intrinsic Muscles of the Foot Figure 11–22a
Muscles that Produce Flexion at the Toes Flexor digitorum longus Flexor hallucis longus: oppose the extensors Toe flexors are on bottom of foot
The Intrinsic Muscles of the Foot Figure 11–22b, c
Summary: Muscles that Move the Foot and Toes Table 11–18
Today Lab 21 Ignore muscles that are not on the list Due Next Week