Lower Leg Complex

Anterior Tibialis

Origin - Laterial condyle and proximal two thirds of the lateral surface of the tibia.

Insertion - Medial plantar aspects of the medial cuneiform and the base of the first metatarsal.

Isolated Function - concentrically accelerates dorsiflexion and inversion.

Integrated Function - Eccentrically decelerates plantarflexion and eversion.  Isometrically stabilizes the arch of the foot.

Lower Leg Complex

Posterior Tibialis

Origin - Proximal two thirds of posterior surface of the tibia and fibula.

Insertion - Every tarsal bone (naviular, cuneiform, cuboid) but the talus plus the bases of the second through the fourth metatarsal bones.  the main insertion is on the navicular tuberosity and the medial cuneiform bone.

Isolated Function - Concentrically accelerates plantarflexion and inversion of the foot.

Integrated Function - Eccentrically decelerates the dorsiflexion and eversion of the foot.  Isometrically stabilizes the arch of the foot.

Lower Leg Complex

Soleus

Lower Leg Complex

Gastrocnemius

Origin - Posterior aspect of the laterl and medial femoral condyles.

Insertion -Calcaneus via the Achilles tendon. 

Isolated Function - Concentrically accelerates plantarflexion.

Integrated Function - Decelerates ankle dorsiflexion.  Isometrically stabilizes the foot and ankle complex.

Lower Leg Complex

Peroneus Longus

Origin - Lateral condyle of tibia, head, and proximal two thirds of the lateral surface of the fibula.

Insertion - Lateral surface of the medial cuneiform and lateral side of the base of the first metatarsal.

Isolated Function - Concentrically plantarflexes and everts the foot.

Integrated Function - Decelerates ankle dorsiflexion.  Isometrically stabilizes the foot and ankle complex.

Hamstring Complex

Biceps Femoris - Long Head

Origin - Ischial tuberosity of the pelvis, part of the sacrotuberous ligament.

Insertion - Head of the fibula.

Isolated Function - Concentrically accelerates knee flexion and hip extension.  Tibial external rotation.

Integrated Function - Eccentrically decelerates knee extension.  Eccentrically decelerates hip flexion.  Eccentrically decelerates tibial internal rotation at mid-stance of the gait cycle.  Isometrically stabilizes the lumbo-pelvic-hip complex and knee.

Hamstring Complex

Biceps Femoris

Origin - Lower on third of the posterior aspect of the femur.

Insertion - Head of the fibula.

Isolated Function - Concentrically accelerates knee flexion and tibial external rotation.

Integrated Function - Eccentrically decelerates knee extension.  Eccentrically decelerates tibial internal rotation.  Isometrically stabilizes the knee.

Hamstring Complex

Semimembranosus

Origin - Ischial tuberosity of the pelvis.

Insertion - Posterior aspect of the medial tibial condyle of the tibia.

Isolated Function - Concentrically accelerates knee flexion, hip extension, and tibial internal rotation.

Integrated Function - Eccentrically decelerates knee extension.  Eccentrically decelerates hip flexion.  Eccentrically decelerates tibial external rotation.  Isometrically stabilizes the lumbo-pelvic-hip complex and knee.

Hamstring Complex

Semitendinosus

Origin - Ishchial tuberosity of the pelvis and part of the scrotuberous ligament.

Insertion - Proximal aspect of the medial tibial condyle of the tibia (pes anserine).

Isolated Function - Concentrically accelerates knee flexion, hip extension, and tibial internal rotation.

Integrated Function - Eccentrically decelerates knee extension.  Eccentrically decelerates hip flexion. Eccentrically decelerates tibial external rotation.  Isometrically stabilizes the lumbo-pelvic hip complex and knee.

Quadriceps Complex

Vastus Lateralis

Origin - Anterior and inferior border of the greater trochanter, lateral region of the gluteal tuberosity, lateral lip of the linea aspera of the femur.

Insertion - Base of the patella and tibial tuberosity of the tibia.

Isolated Function - Concentrically accelerates knee extension.

Integrated Function - Eccentrically decelerates knee flexion, adduction, and internal rotation.  Isometrically stabilizes the knee.

Quadriceps Complex

Vastus Medialis

Origin - Lower region of intertrochanteric line, medial lip of linea aspera, proximal medial supracondylar line of the femur.

Insertion - Base of the patella, tibial tuberosity of the tibia.

Isolated Function - Concentrically accelerates knee extension.

Integrated Function - Eccentrically decelerates knee flexion, adduction, and internal rotation.  Isometrically stabilizes the knee.

Quadriceps Complex

Vastus Intermedius

Origin - Anterior-lateral regions of the upper two thirds of the femur.

Insertion -  Base of patella, tibial tuberosity of the tibia. 

Isolated Function - Concentrically accelerates knee extension.

Integrated Function - Eccentrically decelerates knee flexion, adduction, and internal rotation.  Isometrically stabilizes the knee.

Quadriceps Complex

Rectus Femoris

Origin - Anterior-inferior iliac spine of the pelvis.

Insertion - Base of the patella, tibial tuberosity of the tibia.

Isolated Function - Concentrically accelerates knee extension and hip flexion.

Integrated Function - Eccentrically decelerates knee flexion, adduction, and internal rotation.  Decelerates hip extension.  Isometrically stabilizes the lumbo-pelvic-hip complex and knee.

Hip Musculature

Adductor Longus

Origin - Anterior surface of the inferior pubic ramus of the pelvis.

Insertion - Proximal one third of the linea aspera of the femur.

Isolated Function - Concentrically accelerates hip adduction, flexion, and internal rotation.

Integrated Function - Eccentrically decelerates hip abduction, extension, and external rotation.  Isometrically stabilizes the lumbo-pelvis-hip complex.

Hip Musculature

Adductor Magnus - Anterior Fibers

Origin - Ischial ramus of the pelvis.

Insertion - Linea aspera of the femur.

Isolated Function - Concentrically accelerates hip adduction, flexion, and internal rotation.

Integrated Function - Eccentrically decelerates hip abduction, extension, and external rotation.  Dynamically stabilizes the lumbo-pelvic-hip complex.

Hip Musculature

Adductor Magnus - Posterior Fibers

Origin - Ischial tuberosity of the pelvis.

Insertion - Adductor tubercle on femur.

Isolated Function - concentrically accelerate hip abduction, flexion, and internal rotation.

Integrated Function - Eccentrically decelerates hip abduction, flexion, and internal rotation.  Isometrically stabilizes the lumbo-pelvic-hip complex.

Hip Musculature

Adductiro Brevis

Origin - Anterior surface of the inferior pubic ramus of the pelvis.

Insertion - Proximal one third of the linea aspera of the femur.

Isolated Function - Concentrically accelerates hip adduction, flexion, and internal rotation.

Integrated Function - Eccentrically decelerates hip abduction, extension, and external rotation.  Isometrically stabilizes the lumbo-pelvic-hip complex.

Hip Musculature

Gracilis

Origin - Anterior aspect of the lower body of the pubis.

Insertion - Proximal medial surface of the tibia (pes anserine).

Isolated Function - Concentrically accelerates hip adduction, flexion, and internal rotation.  Assists in tibial internal rotation.

Integrated Function - Eccentrically decelerates hip abduction, extension, and external rotation.  Isometrically stabilizes the lumbo-pelvic-hip complex and knee.

Hip Musculature

Pectineus

Origin - Pectineal line on the superior pubic ramus of the pelvis.

Insertion - Pectineal line of the posterior surface of the upper femur.

Isolated Function - Concentrically accelerates hip adduction, flexion, and internal rotation.

Integrated Function - Eccentrically decelerates hip abduction, extension, and external rotation.  Isometrically stabilizes the lumbo-pelvic-hip complex..

Hip Musculature

Gluteus Medius - Anterior Fibers

Origin - Outer surface of the ilium of the pelvis.

Insertion - Lateral surface of the greater trochanter on the femur.

Isolated Function - Concentrically accelerates hip abduction and internal rotation.

Integrated Function - Eccentrically decelerates hip adduction and external rotation.  Isometrically stabilizes the lumbo-pelvic-hip complex.

Hip Musculature

Gluteus Minimus

Origin - Ilium of the pelvis between the anterior and inferior gluteal line.

Insertion - Greater trochanter of the femur.

Isolated Function - Concentrically accelerates hip adduction and external rotation.

Integrated Function - Eccentrically decelerates hip adduction and external rotation.  Isometrically stabilizes the lumbo-pelvic hip complex.

Hip Musculature

Tensor Fascia Latae (TFL)

Origin - outer surface of the iliac crest just posterior to the anterior-superior iliac spine of the pelvis.

Insertion - Proximal one third of the iliotibial band.

Isolated Function - Concentrically accelerates hip flexion, abduction, and internal rotation.

Integrated Function - Eccentrically decelerates hip extension, adduction, and external rotation.  Isometrically stabilizes the lumbo-pelvic-hip complex.

Hip Musculature

Gluteus Maximus

Origin - outer ilium of the pelvis, posterior aside of sacrum and coccyx, and part of the sacrotuberous and posterior sacroiliac ligament.

Insertion - Gluteal tuberosity of the femur and iliotibial tract.

Isolated Function - concentrically accelerates hip extension and external rotation.

Integrated Function - Eccentrically decelerates hip flexion and internal rotation.  Decelerates tibial internal rotation via the iliotibial band.  Isometrically stabilizes the lumbo-pelvic-hip complex.

Hip Musculature

Psoas

Origin - Transverse and lateral bodies of the last thoracic and all lumbar vertebrae including intervetebral disks.

Insertion - Lesser trochanter of the femur.

Isolated Function - Concentrically accelerates hip flexion and external rotation.  Concentrically extends and roates lumbar spine.

Integrated Function - Eccentrically decelerates hip internal rotation.  Eccentrically decelerates hip extension.  Isometrically stabilizes the lumbo-pelvic-hip complex.

Hip Musculature

Sartorius

Origin - anterior-superior iliac spine of the pelvis.

Insertion - Proximal medial surface of the tibia.

Isolated Function - Concentrically accelerates hip flexion, external rotation, and abduction.  Concentrically accelerates knee flexion and internal rotation.

Integrated Function - Eccentrically decelerates hip extension and internal rotation.  Eccentrically decelerates knee extension and external rotation.  Isometrically stabilizes the lumbo-pelvic-hip complex and knee.

Hip Musculature

Piriformis

Origin - Anterior side of the sacrum.

Insertion - The greater trochanter of the femur.

Isolated Function - Concentrically accelerates hip external rotation, abduction, and extension.

Integrated Function - Eccentrically decelerates hip internal rotation, adduction, and flexion.  Isometrically stabilizes the hip and sacroiliac joints.