4 Muscle Packet

Pectineus - Proximal Attachment

Superior ramus of pubis

Pectineus - Distal Attachment

Pectineal line of femur

Pectineus - Action

Hip adduction, flexion, and internal rotation

Pectineus - Innervation

Femoral L2; may receive a branch from the obturator nerve. Note: 90% are innervated by the femoral nerve

Adductor Longus - Proximal Attachment

Body of pubis inferior to pubic crest

Adductor Longus - Distal Attachment

Middle 1/3 of linea aspera

Adductor Longus - Action

Hip adduction

Adductor Longus - Innervation

Obturator L3 and branch of anterior division

Adductor Brevis - Proximal Attachment

Body and inferior ramus of pubis

Adductor Brevis - Distal Attachment

Pectineal line of femur and proximal linea aspera

Adductor Brevis - Action

Hip adduction, flexion

Adductor Brevis - Innervation

Obturator L3 and branch of anterior division

Adductor Magnus (Hamstring portion) - Proximal Attachment

Ischial tuberosity

Adductor Magnus (Hamstring portion) - Distal Attachment

Adductor tubercle

Adductor Magnus (Hamstring portion) - Action

Hip adduction and extension

Adductor Magnus (Hamstring portion) - Innervation

Tibial L4

Adductor Magnus (Adductor portion) - Proximal Attachment

Ramus of ischium and inferior ramus of pubis

Adductor Magnus (Adductor portion) - Distal Attachment

Gluteal tuberosity, linea aspera, medial supracondylar line

Adductor Magnus (Adductor portion) - Action

Hip adduction, flexion

Adductor Magnus (Adductor portion) - Innervation

Obturator L3, L4 and branches of posterior division

Gracilis - Proximal Attachment

Body and inferior ramus of pubis

Gracilis - Distal Attachment

Superior surface of medial tibia (pes anserine)

Gracilis - Action

Hip adduction, knee flexion and tibial internal rotation

Gracilis - Innervation

Obturator L2

Articularis Genu - Proximal Attachment

Inferior part of the anterior aspect of the femur

Articularis Genu - Distal Attachment

Synovial membrane of the knee and the suprapatellar bursa

Articularis Genu - Action

Pull the synovial membrane superiorly during knee extension

Articularis Genu - Innervation

Femoral L3, L4 Note: derivative of the vastus intermedius

Plantaris - Proximal Attachment

Lateral supracondylar line, oblique popliteal ligament

Plantaris - Distal Attachment

Calcaneus via calcaneal tendon

Plantaris - Action

Weak knee flexion and weak ankle plantarflexion

Plantaris - Innervation

Tibial S1, S2

Popliteus - Proximal Attachment

Lateral condyle of femur, lateral meniscus

Popliteus - Distal Attachment

Posterior tibia superior to soleal line

Popliteus - Action

Tibial internal rotation to “unlock” knee, knee flexion. Retracts lateral meniscus

Popliteus - Innervation

Tibial L4, L5, S1

Extensor Digitorum Longus - Proximal Attachment

Lateral tibial condyle, superior medial fibula, interosseous membrane

Extensor Digitorum Longus - Distal Attachment

Middle and distal phalanges $2nd$ – $5th$ digits

Extensor Digitorum Longus - Action

MP, PIP and DIP extension of $2nd$ – $5th$ digits, ankle dorsiflexion

Extensor Digitorum Longus - Innervation

Deep fibular L4

Fibularis Tertius - Proximal Attachment

Anterior inferior fibula and interosseous membrane

Fibularis Tertius - Distal Attachment

Dorsal surface of base of $5th$ metatarsal

Fibularis Tertius - Action

Ankle dorsiflexion, foot eversion

Fibularis Tertius - Innervation

Deep fibular L4

Flexor Hallucis Longus - Proximal Attachment

Inferior posterior fibula, inferior interosseous membrane

Flexor Hallucis Longus - Distal Attachment

Base of distal phalanx of hallux

Flexor Hallucis Longus - Action

MP and IP flexion of hallux, weak ankle plantar flexion. Supports medial longitudinal arch

Flexor Hallucis Longus - Innervation

Tibial S2, S3

Flexor Digitorum Longus - Proximal Attachment

Posterior surface of tibia inferior to soleal line, fibula via a broad tendon

Flexor Digitorum Longus - Distal Attachment

Base of distal phalanges of $2nd$ – $5th$ digits

Flexor Digitorum Longus - Action

MP, PIP, DIP flexion $2nd$ – $5th$ digits, ankle plantarflexion. Supports longitudinal arches of foot

Flexor Digitorum Longus - Innervation

Tibial S2, S3

Tibialis Posterior - Proximal Attachment

Posterior surface of fibula, posterior surface of tibia inferior to soleal line, interosseous membrane

Tibialis Posterior - Distal Attachment

Navicular tuberosity, 3 cuneiforms, cuboid, sustentaculum tali, bases of $2nd$ - $4th$ metatarsals

Tibialis Posterior - Action

Ankle plantarflexion, foot inversion

Tibialis Posterior - Innervation

Tibial L4, L5

Extensor Digitorum Brevis - Proximal Attachment

Calcaneus (floor of tarsal sinus)

Extensor Digitorum Brevis - Action

Medial Lip: MP extension of hallux

Lateral: MP, PIP, DIP extension of $2nd$ - $4th$ digits

Extensor Digitorum Brevis - Innervation

Deep fibular L5 or S1 or both

Abductor Hallucis (1st Layer) - Proximal Attachment

Medial tubercle of calcaneal tuberosity

Abductor Hallucis (1st Layer) - Action

MP abduction and flexion of hallux

Abductor Hallucis (1st Layer) - Innervation

Medial Plantar S2, S3

Flexor Digitorum Brevis (1st Layer) - Proximal Attachment

Medial tubercle of calcaneal tuberosity

Flexor Digitorum Brevis (1st Layer) - Action

MP and PIP flexion of $2nd$ – $5th$ digits

Flexor Digitorum Brevis (1st Layer) - Innervation

Medial plantar S2, S3

Abductor Digiti Minimi (1st layer) - Proximal Attachment

Medial and lateral tubercles of calcaneal tuberosity

Abductor Digiti Minimi (1st layer) - Action

MP abduction and flexion of $5th$ digit.

Abductor Digiti Minimi (1st layer) - Innervation

Lateral plantar S2, S3

Quadratus Plantae (2nd layer) - Proximal Attachment

Plantar surface of calcaneus.

Quadratus Plantae (2nd layer) - Distal Attachment

Flexor digitorum longus tendons

Quadratus Plantae (2nd layer) - Action

MP, PIP, DIP flexion of $2nd$ – $5th$ digits

Quadratus Plantae (2nd layer) - Innervation

Lateral plantar S2, S3

Lumbricals (2nd layer) - Proximal Attachment

Tendons of flexor digitorum longus

Lumbricals (2nd layer) - Action

MP flexion, DIP and PIP extension $2nd$ – $5th$ digits

Lumbricals (2nd layer) - Innervation

Medial lumbrical ($1st$): Medial plantar S2, S3

Lateral lumbricals ($2nd$ - $4th$): Lateral plantar S2, S3

Flexor Hallucis Brevis (3rd layer) - Proximal Attachment

Cuboid

Flexor Hallucis Brevis (3rd layer) - Action

MP flexion of hallux

Flexor Hallucis Brevis (3rd layer) - Innervation

Medial plantar S2, S3

Adductor Hallucis (3rd layer) - Action

MP adduction of $1st$ digit. Supports transverse arch

Adductor Hallucis (3rd layer) - Innervation

Deep branch of lateral plantar S2, S3

Flexor Digiti Minimi Brevis (3rd layer) - Action

MP flexion of $5th$ digit

Flexor Digiti Minimi Brevis (3rd layer) - Innervation

Superficial branch of lateral plantar S2, S3

Dorsal Interossei (4) (4th layer) - Action

MP abduction and flexion of $2nd$ - $4th$ digits

Dorsal Interossei (4) (4th layer) - Innervation

Lateral plantar S2, S3

Plantar Interossei (3) (4th layer) - Action

MP adduction and flexion of $3rd$ - $5th$ digits

Plantar Interossei (3) (4th layer) - Innervation

Lateral plantar S2, S3