Anatomy of wrist and ankle

Extensor retinaculum

(dorsal carpal ligament, or posterior annular ligament) is an anatomical term for the thickened part of the antebrachial fascia that holds the tendons of the extensor muscles in place. It is located on the back of the forearm, just proximal to the hand.

Flexor retinaculum

(transverse carpal ligament, or anterior annular ligament) is a fibrous band on the palmar side of the hand near the wrist. It arches over the carpal bones of the hands, covering them and forming the carpal tunnel.

Midcarpal joints

-between proximal and distal rows of carpal bones -permit flexion-extension and adduction-abduction

ligaments in ankle

-deltoid ligament medially -lateral ligaments

Deep muscles of posterior compartment of forearm

-extensor indicis -extensor pollicis longus -extensor pollicis brevis -abductor pollicis longus -supinator muscle

Insertion of extensor hallucis longus

Distal phalanx of big toe

Innervation of muscles of forearm

Median nerve Except flexor carpi ulnaris and medial half of flexor digitorum profundus, which are supplied by the ulnar nerve

Insertion of abductor pollicis longus

More proximal and lateral than brevis, attaches to proximal phalanx of thumb

Synovial sheaths in posterior compartment

Surround the tendons and aid their movement deep to retinaculum

Carpal tunnel syndrome

Swellings deep to flexor retinaculum such as synovitis may narrow the space and compress the median nerve

Extensor retinacula

There are usually 2 extensor retinacula that overlie the tendons.

Why do injuries and ulcers to the tibia take long to heal?

There is limited blood supply and it is not covered by muscles so poorly protected

Innervation of posterior compartment

Tibial nerve

ulnar deviation

abduction

hallucis

attaches to the big toe

brevis

short

Superficial peroneal nerve

supplies muscles of the lateral compartment of the leg and skin of anterolateral distal third of the leg and dorsal surface of the foot

Supinator muscle

ulna to radius

Supinators

-biceps brachii (musculocutaneous nerve) -supinator (radial nerve) -brachioradialis (radial nerve) flexes the elbow when in mid-prone position so does a little of both pronation and supination

Intermembranous ossification

-bone initially forms directly in mesenchyme -mesenchymal cells differentiate into osteoblasts directly 2 subtypes -dermal- producing flat bones of the skull (diploic bone) -perichondral- producing cortical bone in the cranial and postcranial skeleton

Other terms for growth plate

-epiphyseal growth plate -epiphyseal plate -epiphyseal cartilage -physis

Superficial extensor muscles of forearm

-extensor carpi radialis longus -extensor carpi radialis brevis -extensor carpi ulnaris -extensor digitorum -extensor digiti minimi

Adductors of the wrist

-flexor carpi ulnaris -extensor carpi ulnaris

Borders of anatomical snuffbox

-medial- tendon of extensor pollicis longus -lateral- tendon of extensor pollicis brevis/abductor pollicis longus -floor- scaphoid bone

Tibiofibular joints

-united by interosseous membrane between shafts -plantarflexion and dorsiflexion at ankle cause passive movements at both tibiofibular joints to accommodate talus during ankle dorsi flexion

Insertion of extensor pollicis longus

DISTAL phalanx of thumb, longer than brevis and forms more of an angle, travelling medially to brevis

Nerve innervating the anterior compartment of the leg

Deep peroneal leg

Muscles that produce adduction and abduction

Extensor/flexor carpi ulnaris/radialis

tibialis

attaches to the tibia

carpi

attaches to the wrist

quadratus

square shape

Joints which provide movements of the ankle

subtalar and midtarsal- produce eversion and inversion other joints permit slight gliding movements between adjacent bones providing flexibility and adaptability to the foot

superficialis

superficial

Joints of ankle and foot

-ankle joint (talocrural) -intertarsal -tarsometatarsal -intermetatarsal -metatarsophalangeal -interphalangeal

Chondrogenesis

-internally limb buds condense and cells differentiate into chondroblasts -chondroblasts secrete cartilage matrix and begin to move apart -when they are completely surrounded by matrix, the cells become chondrocytes -as matrix is secreted, cartilage grows via appositional and interstitial growth

Movements produced by muscles in posterior compartment of the leg

-plantarflexion -flexion of ankle joint -flexion of toes

Proximal tibiofibular joint

-synovial plane joint -between head of fibula and posterolateral aspect of lateral tibial condyle

Insertion of tibialis anterior

Medial cuneiform and 1st proximal end of metatarsal

Insertion of extensor pollicis brevis

PROXIMAL phalanx of thumb, shorter than longus and travels laterally to brevis

Posterior Cutaneous Nerve of the Thigh

S1, S2, S3 sensory only

indicis

attaches to the index finger

longus

long

Pronation/supination of hand

-Occurs at superior and inferior radioulnar pivot joints- NOT AT WRIST JOINT -Radius moves around ulna taking hand with it -from standing with hand in mid-prone position

Actions of superior fibular nerve

-eversion

ligaments in wrist

-radial collateral ligaments -ulnar collateral ligaments -radiocarpal joints

Muscles in anterior compartment of leg

-rectus femoris -vastus lateralis, medialis and intermedius -iliopsoas -sartorius -pectineus =hip flexors or knee extensors and femoral nerve

Eversion

Combined movement of abduction and pronation of the foot accompanies dorsiflexion at the ankle

Movements produced by flexors of forearm

Flexion of the wrist and/or fingers and thumb, pronation of forearm and flexion of elbow joint

Iliohypogastric

L1 sensory only

Ilioinguinal

L1 sensory only

Genitofemoral nerve

L1 and L2 sensory only

Insertion of flexor hallucis longus

Passes laterally to flexor digitorum longus then crosses over to medial of FDL after passing posterior to medial malleolus attaches to big toe (hallux)

radial deviation

adduction

Carpometacarpal joints of 4 fingers

-4 metacarpal bones of fingers articulate with distal carpal bones -plane synovial carpometacarpal joints -functional (immobile) unit -movement restricted by tight palmar and dorsal ligaments

Contents of anatomical snuffbox

-radial artery -cutaneous branches of radial nerve lie superficial to tendons of snuff box Cephalic vein is usually found in the region of the snuffbox and may be used for the insertion of a venous line to administer fluids

Intertarsal joints

-subtalar- talocalcaneal -transverse (mid) tarsal- talocalcaneonavicular and calcaneocuboid -others

Anterior Compartment (Flexors) muscles of the forearm

1. Superficial group; -Pronator teres -Flexor carpi radialis -Palmaris longus -Flexor carpi ulnaris -Flexor digitorum superficialis (P*imps F**k Pr*stitues For Fun) 2. Deep group; -Flexor digitorum profundus -Flexor pollicis longus -Pronator quadratus

Insertion of extensor carpi ulnaris

5th metacarpal bone

Insertion of peroneus brevis

5th metatarsal

Insertion of peroneus tertius

5th proximal metatarsal proximally

Flexor pollicis longus insertion

Distal phalanx of thumb (sits laterally to FD produndus)

digiti minimi

attaches to the little finger

profundus

deep

Flexor digitorum profundus insertion

distal end of phalanx of 4 fingers, between the 2 slips of FD superficialis

Insertion of extensor indicis

fuses with tendon of extensor digitorum, inserts distally on 2nd digit

Contents of the carpal tunnel

-4 tendons of flexor digitorum profundas -4 tendons of flexor digitorum superficialis (both enclosed within same synoviall sheath) -median nerve -tendon of flexor carpi radialis (enclosed within its own synovial sheath in a lateral compartment of the tunnel) -tendon of flexor pollicis longus tendon of palmaris longus (blends with flexor reticulum), ulnar nerve, ulnar artery, palmar cutaneous branches of median and ulnar nerves, and superficial palmar branch of radial artery all lie superficial to flexor reticulum

Median nerve

-C5 6 7 8 T1 -supplies most of muscles in anterior aspect of the forearm and hand and the skin overlying the lateral aspect of the hand -arises from both medial and lateral cords of brachial plexus -lies medial to the brachial artery in the cubital fossa and deep to the bicipital aponeurosis -passes into the forearm where it lies deep -becomes superficial at the wrist -passes through the carpal tunnel with flexor tendons and enters the palm -nerve is vulnerable to injury at the wrist innervates; -palmaris longus, flexor carpi radialis and flexor digitorum superficialis muscles -thenar and lateral lumbrical muscles -flexor pollicis longus, lateral half of flexor digitorum profundas and pronator quadratus muscle -skin of lateral hand and 3 and a half digits -skin of lateral part of the hand and thenar eminence (via palmar cutaneous branch)

Ulnar nerve

-C7, C8, T1 -motor to muscles on anteriomedial aspect of forearm and hand -sensory to skin on medial aspect of hand -arises from median cord of brachial plexus -lies medially to brachial artery, passes behind medial epicondyle of the humerus and enters the medial aspect of the forearm -at the wrist it lies with the ulnar artery and passes over the flexor retinaculum to enter the hand -vulnerable to damage at the elbow and wrist innervates; -flexor carpi ulnaris and medial part of flexor digitorum perfundas -hypothenar, interossei and medial lumbrical muscles -skin over medial aspect of hand and medial one and a half digits

Medial Cutaneous Nerve of the forearm

-C8 and T1 -sensory only

Tendons in the carpal tunnel

-Flexor digitorum superficialis -Flexor digitorum profundus -Flexor pollicis longus -Flexor carpi radialis

Common peroneal nerve

-L4 5 S1 2 -lies along the lateral margin of the popliteal fossa and curves posterior around the neck of the fibula (vulnerable to injury here) -divides into superficial and deep peroneal nerves which supply muscles in the lateral and anterior compartments of the leg respectively -normally contributes to the sural nerve, a cutaneous nerve which innervates skin on the posterolateral surface of the leg and lateral part of the foot

Tibial nerve

-L4 5 S1 2 3 -lies in popliteal fossa and passes into the leg between the gastrocnemius and soleus -lies with the posterior artery and enters the sole of the foot behind the median malleolus -divides in the foot into the medial and lateral plantar nerves which supply the muscles of the sole of the foot and the skin overlying the medial and lateral aspects of the sole of the foot (similar arrangement to the ulnar and median nerves in the hand) innervates; -muscles in the posterior compartment of the leg and foot

Lateral compartment leg muscles

-Peroneus longus -Peroneus brevis Actions- eversion

Medial Cutaneous Nerve of the arm

-T1 -sensory only

Anterior Compartment (Dorsiflexion) leg muscles

-Tibialis anterior* -Extensor hallucis longus -Extensor digitorum longus -Peroneus tertius Actions- dorsiflexion and inversion*

Muscles of medial compartment of leg

-adductor longus, bravis and magnus -gracialis -obturator externus =hip adductors and obturator nerve

Compartments of the leg

-anterior -posterior -lateral compartments are enclosed by tough fascia, any swelling may lead to increased pressure which could cause compression of blood vessels compromising blood supple to muscles in the compartment

Intercarpal joints

-between adjacent carpal bones -plane synovial joints -allow slight gliding movements -strong ligaments permit limited movement between individual carpal bones

Radiocarpal (wrist) joint

-between concave distal radius and convex scaphoid, lunate, triquetrum -synovial ellipsoid joint -allows flexion-extension, adduction-abduction (radial/unlar deviation) -completely enclosed by fibrous capsule -palmar and dorsal ligaments strengthen anteriorly and posteriorly -radial and ulnar collateral carpal ligaments strengthen medially and laterally -fibrocartilage disk between head of ulna and carpal bones

Muscles in anterior compartment of arm

-biceps brachii -brachialis -coracobrachialis =should and flexors and musculocutaneous nerve

Endochondral ossification

-bones form in pre-existing hyaline cartilaginous template -perichondrium is triggered to stop producing chondrocytes and instead produces osteoblasts -at this point, it becomes a periosteum and a collar of bone forms around the cartilage model via intermembranous ossification (is classified as periosteal or intramembranous as did not technically form within cartilage but around it) -mesenchymal cells differentiate into chondrocytes which produce a cartilage bone which is then replaced by bone -forms cancellous (trabecular bone) -found in cranial and post-cranial skeleton -chondrocytes contained in the cartilage template become enlarged and form thin irregular plates of matrix between them -as this continues, matrix changes properties , isolating chondrocytes from their nutrients and causing them to die -developing bone is penetrated by growing blood vessels which contain mesenchymal stem cells -mesenchymal stem cells differential into osteoprogenitor cell which come into contact with the cartilage matrix -they then differentiate osteoblasts and begin to lay down bone matrix (osteoid) to the framework -this first occurs in diaphysis and is known as the primary ossification centre -POC doesn't always expand to fill an entire cartilage template, instead in some bones (eg long bones) secondary ossification centres/epiphyses develop. -diaphyses and epiphyses develop adjacent to primary ossification centre, seperated by epiphyseal growth plate which permits growth

Cartilage repair

-cartilage has very limited capacity for repair and healing after injury, due to avascularity, immobility of chondrocytes and limited proliferation in normal tissues -injury in perichondrium (not present in articular cartilage), some repair can result from activity of pluripotent progenitor cells present in perichondrium -in articular cartilage (absent of a perichondrium) injuries extending into the subchondral bone may also permit some repair -in both examples, repair is limited and the newly formed tissue does not possess the properties of original cartilage -typical cartilage injuries result in irreversible cartilage degeneration, which eventually results in changes to overlying bone

Ankle joint

-distal ends of tibia and fibula form tight mortise which clasps talus at ankle (talocrural) joint -synovial hinge joint -allows plantarflexion (F) and dorsiflexion (E) -joint capsule is thin and weak anteriorly and posteriorly to accommodate movement -lined by loose synovial membrane -strengthened medially and laterally by collateral ligaments

Wrist joint plan

-ellipsoid joint -movements are flexions/ extensions, adduction/abduction, circumduction -bones are radius and carpal bones (and fibrocartilage disk on ulna) -cartilage covers the joint surfaces with fibrocartilage disk on ulna -capsule around the joint -synovial membrane lines the capsule -collateral ligaments

Abductors of the wrist

-flexor carpi radialis -extensor carpi radialis longus -extensor carpi radialis brevis (flexors and extensors work together)

Superficial layer of anterior compartment of forearm (flexor) muscles

-flexor carpi ulnaris -flexor carpi radialis -flexor digitorum superficialis -pronator teres -palmaris longus (not always present)

Deep muscles of posterior compartment of the leg

-flexor digitorum longus -flexor hallucis longus -tibialis posterior

Deep layer of anterior compartment of forearm (flexor) muscles

-flexor digitorum profundus -flexor pollicis longus -pronator quadratus

Superficial muscles of posterior compartment of the leg

-gastrocnemius (2 heads unite to form Achilles tendon/tendocalcaneus, attached to calcaneus) -soleus (tendon fuses with anterior surface of tendocalcaneus) -plantaris, if present

Distal (inferior) radioulnar joint and interosseous membrane

-head of ulna articulates with ulnar notch at distal end of radius -joint separated from radiocarpal (wrist) joint by fibrocartilage articular disk -articulation is surrounded by loose fibrous capsule and synovial membrane -allows pronation and supination

Ankle joint plan

-hinge joint -movements are flexion and extension (NOT inversion or eversion) -bones are tibia, fibula and talus -cartilage covers joint surfaces -capsule around the joint -synovial membrane lines the capsule -collateral ligaments

Limb development

-limb buds are visible from 4th week of development -initially consist of mesenchymal core (mesoderm origin) and ectodermal layer -as limbs grow and lengthen, chrondrogenesis and osteogenesis occurs as mesenchyme differentiates -lower limb development is typically delayed by 1-2 days -during week 7, limbs under go rotation -upper limbs rotate 90 degrees laterally -lower limbs rotate 90 degrees medially

Carpal tunnel

-location- anterior wrist -tunnel shape -boundaries are carpal bones and wrist flexor retinaculum -contains the medial nerve and tendons -clinically- carpal tunnel syndrome (the median nerve is compressed by swelling of tendons as it travels through the wrist at the carpal tunnel and causes pain, numbness and tingling, in the part of the hand that receives sensation from the median nerve)

Collateral ligaments of ankle joint

-medial (deltoid) ligament- strong, triangular bands that radiate from medial malleolus of the tibia to the talus, calcaneus and navicular -lateral ligaments- bands that pass from the lateral malleolus of the fibula to the talus (anterior and posterior talofibular ligaments) and the calcaneus (calcaneofibular ligament) lateral lligament is not as strong as medial, most ankle sprains are from the lateral ligaments. Ankle is less stable when foot is plantarflexed, talus can be moved passively from side to side.

Appositional growth

-new cartilage is formed at the surface of existing cartilage -these cells originate from the surrounding perichondrium

Interstitial growth

-new cartilage is formed within an existing cartilage mass -these cells are formed via chondrocyte mitosis within lacunae

Pronators

-pronator terres (median nerve) -pronator quadratus (median nerve) -brachioradialis (radial nerve) flexes the elbow when in mid-prone position so does a little of both pronation and supination

Joints of wrist and hand

-radiocarpal joint (wrist) -intercarpal and midcarpal -carpometacarpal -metacarpophalangeal -interphalangeal

Muscles in posterior compartment of leg

-semimembranosus -semitendinosus -biceps femoris =hip extensors or knee flexors and sciatic nerve

Interosseous membrane

-strong fibrous sheet that passes obliquely between radius and ulna -acts to transmit forces from the hand up to radius to the ulna, elbow joint and humerus -also provides attachment between radius and ulna and increases surface area for attachment of deep muscles of forearm

Ligaments supporting the intertarsal joints

-subtalar joint strengthened by talocalcaneal ligament occupies the tunnel (sinus tarsi) between anterior and posterior joints of talus with the calcaneus -intertarsal joints- strengthened by dorsal and plantar ligaments -calcaneus and navicular- strengthened by strong spring (calcaneonavicular) ligament -calcaneus and cuboid- strengthened by long plantar ligament and short plantar ligament (found deep to long plantar ligament)

Carpometacarpal joint of thumb

-synovial saddle joint -between 1st metacarpal and trapezium -anatomical position of thumb is at right angles to dorsal surfaces of fingers movements of thumb; -adduction/abduction (sagital plane) - forward to anatomical position at right angles to plane of palm (adduction is reverse) -flexion/extension (coronal plane) - away from/ towards palm -opposition- moving thumb towards little finger, complex interactions of F E A A due to saddle shape

Bone remodelling

-throughout life, bones under modelling and remodelling via removal of bone (osteoclast activity) and stimulation deposition of new bone (osteoblast activity) -enables accommodation of changes in stress and strain of bone and enables elimination of microscopic damage

Muscles of anterior compartment of the leg

-tibialis anterior -extensor hallucis longus -extensor digitorum longus -peroneus tertius

Muscles in posterior compartment of arm

-triceps brachii =shoulder and elbow extensors and radial nerve

Functions of interosseous membrane

-united tibia and fibula -separates muscles in anterior and posterior compartments -forms muscle compartments, with deep fascia -provides attachment for muscles

Distal tibiofibular joint

-very strong fibrous syndesmosis -between inferior ends of tibia and fibula -prevents separation of the two bones during weight bearing

Posterior Compartment (Extensors) muscles of the forearm

1. Superficial group; -Brachioradialis -Extensor carpi radialis longus -Extensor carpi radialis brevis -Extensor digitorum -Extensor digiti minimi -Extensor carpi ulnaris 2. Deep group; -Supinator -Abductor pollicis longus -Extensor pollicis longus -Extensor pollicis brevis -Extensor Indicis

Posterior Compartment (Plantarflexion) leg muscles

1. Superior group; -Gastrocnemius -soleus -plantaris 2. Deep group; -Tibialis posterior* -Flexor hallucis longus -Flexor digitorum longus -Popliteus** Actions- plantarflexion, inversion* and actions on the knee**

Insertion of extensor carpi radialis longus

2nd metacarpal bone

Insertion of extensor carpi radialis brevis

3rd metacarpal bone

Popliteus

Attached to lateral condyle of femur, most significant function is "unlocking" the knee by laterally rotating the femur on the tibia at the start of flexion Fibres are also attached to lateral meniscus and move it during flexion to prevent it from being trapped

Osteogenesis

Bone formation via complex, interelated and synchronised processes; -cell migration -cell division (mitosis) -differentiation -secretion -extracellular mineralisation -resorption -skeleton starts to form in the early embryo -development and growth of skeleton continues after birth up to skeletal maturation (which occurs during adolescence) -bones are formed via 2 pathways, defined by the initial environment in which the bone develops rather than final microanatomy -2 pathways- intermembranous ossification and endochondral ossification -these are only mechanisms by which bones grow initially, bone is replaced during bone remodelling

Bone repair

Bone has good capacity for repair, provided there is; -a viable periosteum -good apposition between fragments -immobilisation of fragments Repair of bone occurs via both endochondral and intramembranous ossification and occurs via 4 stages; 1. Hematome/ inflammatory phase - blood accumulates between fractured ends -osteocytes and marrow cells undergo cell death -an inflammatory response is limited -macrophages and polymorphonuclear leukocytes migrate into a fibrin scaffold forming an inflammatory granuloma 2. Reparative phase- soft callus formation -cells from peristeum and endosteum initiate the repair of the fractuse -capillary buds extend into the granuloma -cartilage is formed and a soft callus contributes to the stability of the bone -trabeculae gradually replace the cartilage 3. Reparative phase- hard callus formation -osteoblasts from osteoprogenitor cells become active -the ends become enveloped in the hard callus -necrotic ends of fractured bone are resorbed 4. Remodelling phase -osteoclasts reabsorb excessive and misplaced trabeculae -new bone is laid down by osteoblasts -new haversian systems are formed

Inversion

Combined movement of adduction and supination of foot accompanies plantarflexion at the ankle

Insertion of extensor digitorum longus

Distally to 4 lateral toes by tendon which splits into 3 slips to attach to middle and distal pharanx is similar arrangement to in the hand (2 on outside attach proximally, 1 in middle goes distally)

Muscles in the lateral compartment of the leg

Evertors of the foot, attached to the fibula -peroneus longus -peroneus brevis

Flexor retinaculum

Extends between medial malleolus and calcaneus and overlies the tendons of deep muscles of posterior compartment of the leg

Flexor retinaculum and finger sheaths

Hold flexor tendons in position at the wrist and ensure when the flexor muscles contract the tendons do not "bow out" at the wrist or in the fingers. When muscles contract, the tendons move and this is facilitated by synovial sheaths which surround the tendon.

Synovitis

Inflammation of synovial sheaths, may cause swelling of sheaths and restricts movement of tendons, causing pain.

Lateral cutaneous nerve of thigh

L2 and L3 sensory only

Attachment of superficial muscles of the posterior compartment of the arm (extensors)

Lateral epicondyle and spuracondylar ridge of humerus

Brachioradialis

Lateral supercondylar ridge of humer proximally and distal end of radius. Flexor of the elbow when in mid-pronated position

Proximal attachment of superficial flexors (anterior compartment) of the forearm

Medial epicondyle (common flexor origin) and supracondylar ridge of humerus

Insertion of flexor digitorum longus

Passes posterior to medial malleolus and divides in foot to attach to distal phalanx of each of lateral 4 toes (medial to flexor hallucis longus)

Innervation of extensor/posterior compartment of forearm

Radial nerve via a deep branch- posterior interosseous nerve

What does a fall on an outstretched hand dislocate?

Radiocarpal and/or midcarpal joints involving anterior dislocation of lunate or scaphoid fracture (characterised by pain in anatomical snuffbox)

Innervation of lateral compartment of the leg

Superficial peroneal nerve

Insertion of peroneus longus

Tendon lies posterior to lateral malleolus and crosses over sole of foot obliquely and is attached to medial side of foot on the first metatarsal and medial cuneiform Peroneal muscles are tightly invested with deep fascia and tendon of peroneus longus has an important role in maintaining the arches of the foot.

How to remember anterior superficial muscles of forearm

There are five, like five digits of your hand. Place your thumb into your palm, then lay that hand palm down on your other arm. Your 4 fingers now show distribution: spells PFPF [pass/fail, pass/fail]: Pronator teres, Flexor carpi radialis, Palmaris longus, Flexor carpi ulnaris Your thumb below your 4 fingers shows the muscle which is deep to the other four: Flexor digitorum superficialis.

Is the injury to a peripheral (named) nerve or a spinal cord segment/plexus roots?

You must consider: 1. the cutaneous distribution map for peripheral nerves to determine the sensory loss caused by damage of that peripheral nerve. 2. the muscles that are supplied by that peripheral nerve to determine which muscles will be weakened and atrophied.

Deep peroneal nerve

accompanies the anterior tibial artery and innervates the muscles of the anterior compartment of the leg and the skin overlying the adjacent sides of the first and second toes

pollicis

attaches to the thumb

Flexor carpi radialis insertion

base of 2nd and 3rd metacarpal bones

Flexor digitorum superficialis insertion

by 2 slips to middle phalanx of the 4 fingers, splits and tendon of flexor digitorum profundus goes through middle, FDS on either side FD superficialis is superior and slightly medial to FD profundus

teres

cylindrical shape

Insertion of extensor digiti minimi

distal of 5th finger (little finger)

Insertion of extensor digitorum

distal phalanges of 4 fingers

Carpal tunnel borders

flexor reticulum attached medially to the pisiform and the hook of hamate and laterally to scaphoid tubercle and trapezium, and the carpal bones

Insertion of tibialis posterior

navicular bone

The epiphyseal growth plate

organised into 5 zones from outermost to diaphysis 1. Zone of reserve cartilage (ZRC)- does not undergo proliferation and organisation into columns 2. Zone of proliferation (ZP)- chondrocytes in this zone undergo proliferation and organisation into columns and cells are larger than in ZRC and produce cartilaginous matrix 3. Zone of hypertrophy (ZH)- chondrocytes generally enlarged, matrix compressed between cells, vascular invasion initiated 4. Zone of classified cartilage (ZCC)- chondrocytes degenerate, cartilaginous matrix calcifies, forming scaffold for new bone and chondrocytes closer to diaphysis die 5. Zone of resorption (ZR)- calcified cartilage is exposed to osteoprogenitor cells which become osteoblasts and initiate ossification -the plate is responsible for bone growth -thickness remains relatively constant as growth in ZP equals resorption in ZR -ZP becomes less active as person reaches skeletal maturity, thus epiphyseal plate get smaller/thinner -eventually growth stops- epiphyseal closer

Flexor carpi ulnaris insertion

pisiform, hook of hamate and base of 5th metacarpal bone

Actions of deep fibular nerve

• Dorsiflexion • Inversion • Extension of the toes

Actions of tibial nerve

• Plantarflexion • Flexion of the knee* • Flexes toes • Inverts foot

Actions of radial nerve

• Supination • Extension of hand at the wrist • Extension of the fingers • Abd/Adduction at the wrist