Functional anatomy of the muscles of the limbs

1. Development of the limb muscles

2. Peculiarities of the limb muscles

3. Auxiliary apparatus of the limb muscles

4. Differences of the upper and lower limb muscles

5. Topography of the upper limb

6. Topography of the lower limb

7. Weak places of the pelvis and hernias

Development of the limb muscles • It is supposed that muscles of the limbs are developed from the cells of the ventral myotomes which migrate into the mesenchyme bud of the limb.• Muscles which are inserted to the bones of free limb with both ends form the Autochthonous group of the muscles.• Some muscles which are derivatives of migrated cells move one its end to the trunk and become inserted to it. Such muscles form the Trunkopetal group of the muscles (e.g. pectoral major and minor muscles, latissimus dorsi muscle).• The third group is developed from the myotomes of the trunk and is inserted with one end to the bones of the limb forming the Trunkofugal muscles ( trapesium m., rhomboid mm., levator scapulae m., anterior serrate m).• At the lower limbs trunkofugal muscles are absent.• Trunkopetal muscles of the lower limb: greater psoas m., quadratus lumborum m..

Peculiarities of the limb muscles•Big amount of the long muscles

•Presence of big amount of muscular annexions:

- retinaculi,

- synovial vagines,

- synovial bursae,

- tendinous vinculae,

- fibromuscular canals.

Localization of the limb muscles

•Muscles have perpendicular direction to the axis of movement at the joint.

•Minimum one pair of muscles /one by one for opposite movements/ exist for each axis.

•Function of each muscle depends on the its position to the axis of movement.

Retinaculi of the upper limb

Retinaculum flexorumCanalis carpi radialis: •tendon m. flexor carpi radialis.

Canalis carpalis: •Synovial vagines of tendons of muscles flexor digitorum, •tendon of m.flexoris pollicis longus, •nervus medianus.

Canalis carpi ulnaris: •Arteria ulnaris•Vena ulnaris•Nervus ulnaris

Retinaculi of the upper limb

Retinaculum extensorum/6 canals transmitting tendons/

I - m.abductor pollicis longus m.extensor pollicis brevis

II - m.extensor carpi radialis longus m.extensor carpi radialis brevis

III - m.extensor pillicis longus

IV – m.extensor digitorum m. extensor indicis

V - m. extensor digiti minimi

VI – m.extensor carpi ulnaris

Synovial sheaths of the palmar and dorsal surface of the hand

Retinaculi and synovial sheaths of the lower limb

Retinaculum extensorum• It presses the tendons of the anterior leg muscles to the bones• It has 2 parts:1. Upper /between the leg bones above the malleoli/ 2. Lower /distally in front of the ankle joint, Y-shaped/- originates from the lateral surface of the calcaneus and tarsal sinus- separates into two bands: a) superior - passes to the medial malleolus;b) inferior – to the navicular and medial cuneiform bones•It splits into a superficial and deep layers the extensor tendons forming four fibrous canalsI – synovial vagine of the extensor digitorum longus andperoneus tertius mII - synovial vagine of the extensor hallucis longusIII- synovial vagine of the tibialis anterior muscleIV – blood vessels and nerve

Retinaculi and synovial sheaths of the lower limb

Retinaculum flexorum•Passes from the calcaneus to the medial malleolus

•Forms 4 osteofibrous canals:I – synovial vagine of the tibialis posterior,II - synovial vagine of the flexor digitorum longus,III – synovial vagine of the flexor hallucis longus,IV – posterior tibial artery and tibial nerve.

Retinaculi and synovial sheaths of the lower limb

Retinaculum peroneorum

It has 2 parts:

1) Upper

- from the lateral malleolus to

the calcaneus,

- transmits the common synovial

vagine of the peroneus longus and

brevis muscles

2) Lower

- located on the lateral surface of

he calcaneum,

- transmits separated synovial

vagines of the peroneus longus

and brevis muscles.

Synovial vagines and the grooves of the plantar surface

Differences of the muscles of the upper and lower limbs

• Amounts of the muscles of upper limbs is bigger

• Volum and weight of the muscles is bigger at the lower limbs

• Lower limbs haven’t group of the muscles pronators

• Pelvic girdle doesn’t have proper muscles, these muscles are well developed at the shoulder girdle

• Flexors prevail at the upper limbs, extensors – at the lower limbs.

• Lower limbs have well developed group of adductors.

• Muscles of the upper limbs have small surface of attachment to the bones.

• At the upper limb point of effort is placed closely to the fulcrum than at the lower limb.

Topography of the upper limb1. Axillary fossa• It is seen in abduction• It is bounded: inferiorly by the greater pectoral m. in front; by the latissimus dorsi and teres major m. – behind;medially – by an imaginary line between borders of these mm. on the chestlaterally – by a connecting line on the inner surface of the upper arm.

2. Axillary cavityAnterior wall – major and minor pectoral muscles:3 triangles clavipectoral pectoral infrapectoral;Posterior wall – subscapular m. teres major m. latissimus dorsi m.;2 oppenings trilaterum = triangular quadrilaterum = quadrangular;Medial wall – serratus anterior m.Lateral wall – humarus + muscles.

Topography of the shoulder girdle

1. Deltoideopectoral triangle (groove) - a

2. Lateral and medial bicipital grooves – b, c

Topography of the upper limb

1. Canal of the radial nerve = canalis spiralis = canalis humeromuscularis:

• between the humerus and triceps muscle

2. Fossa of beauty:• on the posterior surface of

the elbow joint

3. Gluter’s triangle and line:

• connect the epicondyles and apex of the olecranon

Topography of the forearm

1. Canal of the ulnar nerve: between the medial epicondyle, proximal ulna and origin of the forearm flexors

2. Canalis supinatorius: between the supinatorius muscle and radius

3. Pirogov’s space: between the third and fourth layers of the forearm muscles at its distal part.

Topography of the forearmand hand

Antebrachial grooves:Lateral = radial: between brachioradial and flexor carpi radialis mm;

Median: between flexor carpi radialis and flexor digitorum superficialis mm ;

Medial = ulnar: between flexor digitorum superficialis and flexor carpi ulnaris mm .

Elbow fossa: laterally – brachioradial m.,

medially – pronator teres m.,

superiorly – brachial m..

Anatomical snuff-box

Suprapirifom and infrapiriform

oppenings

The piriform foramen passes through the greater sciatic foramen, above and below which narrow openings remain and transmit the gluteal vessels and nerves.

Lacuna musculorum:Above – inghinal lig,; laterally – sartorius m.; medially – arcus ileopectineus.

Lacuna vasorum:Above – inghinal lig,; laterally – arcus ileopubicus; medially – lig. lacunare; behind – arcus ileopectineus.

Femoral triangle:Laterally – sartorius m.;Above – inghinal ligament;Medially – adductor longus m.

Canalis adductorius:Laterally – medial belly of cvadriceps m.;Medially – adductor magnus m.;Anteriorly - membrana vastoadductoria.

•Under normal conditions doesn’t exist.

•Walls:

Lateral – femoral vein;

Posterior – deep layer of fascia lata femoris;

Anterior – inghinal ligament and superior horn of the crescent-shaped margin of fascia lata.

•There is a narrow opening in the medial corner of lacuna vasorum – the femoral ring = inlet

Laterally – femoral vein;

Anterior and superior – Poupart’s ligament;

Medially – lacunar ligament;

Posterior – pectineal ligament.

• Outlet – chiatus saphenus.

Femoral canal

Canals of the leg

•Grouber’s canal =canalis cruropopliteus• Extends between the superficial and deep mm. of the leg. • It gives a branch – canalis musculoperoneus inferior formed by the middle third of the fibula and the flexor hallucis longus.• Canalis musculoperoneus superior – it is placed in the upper third of the leg, between the fibula and peroneus longus muscle.• Pirogov’s canal – it is a fascial canal located between two heads of the gastrocnemius muscle.

Weak places of the pelvis

1. Obturator canal

2. Suprapirifom foramen

3. Infrapiriform foramen

Obturator Hernia: This extremely rare abdominal hernia develops mostly in women. This hernia protrudes from the pelvic cavity through an openingin the pelvic bone (obturator foramen). This will not show any bulge but can act like a bowel obstruction and cause nausea and vomiting.

Ischiatic and obturator hernias

Ischiatic hernias:1. Suprapiriform hernia;2. Infrapiriform hernia;3. Hernia of the lesser piriform foramen

Perineal hernias

2 – anterior peroneal hernia;7 - posterior peroneal hernia.

Femoral hernias

Femoral Hernia: It occurs when the intestine enters the canal carrying the femoral artery into the upper thigh. Femoral hernias are most common in women, especially those who are pregnant or obese.

End