5. Lower Limb Foot And Ankle Flashcards
Tibia and fibula
- Bones are triangular in shape
- Interosseous membrane = between tibia and fibula
- Intermuscular septa (anterior and posterior)
- Compartments (anterior and lateral)
- Medial surface of tibia = subcutaneous
Tibia function
• Tibia is involved with knee joint and takes weight of lower limb
Fibula function
• Fibula important in ankle joint stability – but doesn’t take weight
Ankle bones
3 bones of the Ankle: tibia, fibula and talus
• Medial malleolus: expansion of tibia
• Lateral malleolus: expansion of tibia
– More prominent, more posterior and 1cm more distal
Ankle joint - synovial joint
Uni-axial: dorsi and plantar flexion
– around axis passing through talus
- Synovial joint – articular surfaces covered in hyaline cartilage
- Mortise joint= a hole / recess cut into a part which is designed to receive a corresponding projection
Tibiofibular syndemosis
Inferior tibiofibular joint with 3 ligaments
– Anterior tibiofibular
– Interosseous membrane btw tibia and fibula
– Posterior tibiofibular
These ligaments hold the ankle joint together
• Can be injured
3 zones of foot and bones
- Forefoot – metatarsals and phalanges
- Midfoot – navicular, cuboid, cuneiforms
- Hindfoot – talus and calcaneus
Great toe=hallux=1st toe
• Sesamoids = bone inside a tendon
Bones of the forefoot
Numbered from medial side 1st is big toe, 5th is pinky
• Each bone has base, shaft and head
- Phalanges
- Metatarsals
- Tarsometatarsal line
Forefoot -phalanges
– Each digit has 3 phalanges, proximal, middle, distal (except 1st)
• Apart from big toe that only has 2
Forefoot- metatarsals
– Bases articulate medially with cuneiforms and laterally with cuboid
– Head artic with proximal phalanx
– 1st and 5th bases have large tuberosities tendon attachments
Forefoot - tarsometatarsal line
– splits foot into forefoot and midfoot
• Diagonal line
Bones of the midfoot
- Navicular (L. little ship)
- cuboid
- Cuneiforms (L cuneus, wedge shaped)
Midfoot - navicular
• Boat shaped
– between talus and 3 cuneiforms
Midfoot - cuboid
• Between calcaneus and Metatarsals
Midfoot-Cuneiforms (L cuneus, wedge shaped)
- Between navicular and metatarsals
* 3 of these
Bones of the hindfoot
Talus
Calcaneus
Hindfoot- Talus
Most of surface covered by cartilage (no muscle / tendon attachments)
• Superior surface, (trochlea) receives weight of body
• Transmits weight to calcaneus and forefoot
• Head, neck, body
Fractures – can occur through neck of talus, disrupt blood supply = avascular necrosis
Ankle joint – stability
- The Trochlea is narrower posteriorly
- Dorsiflex (like walking up a hill) – forces wide anterior part of trochlear posteriorly between malleoli – spreading the tibia and fibula slightly apart & tightening the 3 tibiofibular ligaments
- Going down a hill = plantar flexion
- Ankle relatively unstable in plantar flexion – most injuries occur
Hindfoot – calcaneus
Transmits weight
• Posterior part has calcaneal tuberosity = bit that you stand on
- Articulates with talus (talus is above it)
- Anterior surface articulates with cuboid
- Medial has sustentaculum tail (talar shelf)
Ankle collateral ligament
• Joint capsule thin = allows movement
Lateral ligament
• Anterior talofibular
• Calcanofibular ligament
• Posterior talofibular
Medial ligament (deltoid) • Medial malleolus to 2 talus, 1 calcaneus and 1 navicular (4 parts)
Lateral ligament is weaker than the strong medial ligament
Lateral ligament
- Anterior talofibular
- Calcanofibular ligament
- Posterior talofibular
Medial ligament
• Medial malleolus to 2 talus, 1 calcaneus and 1 navicular (4 parts)
Foot joints -role
Flexion and extension occurs in ankle and forefoot
2 foot joints
- Interphalangeal joins
* Metatarsalphalangeal joints
Subtalar joint
- where talus articulates with calcaneus – between talus and calcaneus
- Orthopaedic surgeons include the talocalcaneal part of talocalcaneonavicular joint – between talus, calcaneal and neviculum
Transverse tarsal
• compound joint: calcaneocuboid joint and talonavicular part of talocalcaneonavicular joint
3 ligaments - important for maintaining longitudinal arch of foot
Spring Ligament (Plantar Calcaneonavicular)
Short plantar ligament (Plantar calcaneocuboid)
Long plantar Ligament
Spring Ligament (Plantar Calcaneonavicular)
– between sustentaculum tali and navicular
– Supports head of talus
Short plantar ligament (Plantar calcaneocuboid)
– between the calcaneus and cuboid
Long plantar Ligament
– Also calcaneus to cuboid
– some fibres extend to bases of metatarsals (form a tunnel for peroneus longus)
Anterior compartment - function
Dorsiflexor or extensor compartment
• Dorsiflex ankle, plus each muscle does one other thing
If anterior compartment wasn’t working you would have foot drop so toes would drag against the ground
• Important for
– swing phase of walking
– posture
Boundaries of the anterior compartment
- I/Ointerosseous membrane
- Lateral surface of tibia
- Medial surface of fibula/ anterior intermuscular septum
- Deep fascia of leg
What does the anterior compartment contain
- 4 muscles
* Deep peroneal nerve
Extensor retinaculum
- Thickenings of fascia - prevent tendons from bowstringing
- Physically holds tendons close to the bone
- Superior extensor retinaculum
- Inferior extensor retinaculum
2 parts of Extensor retinaculum
- Superior extensor retinaculum
* Inferior extensor retinaculum
Muscles of anterior compatment
tibialis anterior
extensor digitorum longus
Extensor hallucis longus
Peroneus (fibularis) tertiarus
tibialis anterior
Against tibia
- P: Lateral surface of tibia and I/O membrane
- D: Medial cuneiform and base of 1st metatarsal
- I: Deep Peroneal (fibular) (L4,L5)
- A: Dorsiflexes ankle and inverts foot
- With tibialis posterior invert foot
extensor digitorum longus
• P: Medial surface of fibula and I/O membrane
• D: Forms extensor expansion over proximal phalanxes of lateral 4 digits
– divides into central band
- inserts into base of Middle phalanx
– 2 lateral bands -converge and insert into base of Distal phalanx
• I: Deep Peroneal (fibular) (L4,L5)
• A: Dorsiflexes ankle and extends lateral 4 digits
Extensor hallucis longus
Deep muscle
• P: Middle part of anterior surface of fibula and I/O membrane
• D: Base of distal phalanx of hallux
• I: Deep Peroneal (fibular) (L4,L5)
• A: Dorsiflexes ankle and extends great toe
Peroneus (fibularis) tertiarus
Like and extension of extensor hallucis
Not always present
• P: Inferior 1/4 anterior fibula and I/O membrane
• D: Dorsum of base of 5th metatarsal
• I: Deep Peroneal (fibular) (L4,L5)
• A: Dorsiflexes ankle and helps in foot eversion
• May help to protect anterior tibiofibular ligament – most commonly injured nerve
Nerve of anterior compatment
Deep peroneal nerve
Deep peroneal nerve
Arises from common peroneal nerve
• Accompanies anterior tibial artery on the I/O membrane
• In foot supplies muscles extensor digitorum and hallucis brevis
And supplies 4 muscles above
• and small area of skin in dorsum of 1st webspace
Lesion can result in foot drop
Artery of anterior compartment
Anterior tibial
Anterior tibial artery
• Comes off popliteal through popliteal fossa
- Passes anteriorly through a gap in the superior part of the I/O membrane
- Descends on membrane with DPN
- Changes name midway between malleoli to dorsalis paedis artery
- Palpated lateral to EHL tendon
Palpation of pulses
Find the • Popliteal • Femoral • Posterior tibial • Dorsalis pedis
Learn to palpate those 4
Lateral compartment
Evertor compartment
• Important for
– walking
– posture (resist when centre of gravity shifted medially)
Lateral compartment boundariés
- anterior intermuscular septum
- lateral surface of fibula
- posterior intermuscular septum
- deep fascia
2 muscles and a retinaculum
Peroneaal (fibular) retinaculum
- Tendons pass with common synovial sheath behind lateral malleolus
- Peroneus brevis is in contact/ grooves lateral malleolus
- Peroneus longus lies posterior to brevis (not in contact with malleolus)
Peroneus (fibularis) longus
- P: Head & superior 2/3 of lateral surface of fibula
- D: Passes through groove in cuboid and to base of 1st metatarsal and medial cuneiform
- I: Superficial peroneal (fibular) nerve, (L5, S1, S2)
- A: Evert foot and weak plantar flexor of ankle
Peroneus (fibularis) Brevis
- P: Inferior 2/3 of lateral surface of fibula
- D: Tuberosity on base of 5th metatarsal
- I: Superficial peroneal (fibula) nerve, (L5, S1, S2)
- A: Evert foot and weak plantar flexor of ankle
Nerve of lateral compartment
Superficial peroneal (fibular)
Superficial peroneal (fibular)
- Arises from common peroneal nerve
- Descends in lateral compartment – supplies muscles
- Become subcutaneous
- Supplies skin distal 1/3 anterolateral surface leg
- Splits into branches that supply most of skin dorsum of foot
Blood vessels of lateral compartment
• Perforating arteries and veins from anterior tibial artery and peroneal (fibular) artery
There isn’t one dedicated atery in the lateral compatment
Plantar skin
• Sensate – feeling
• wt bearing areas thicker – thicker skin
– heel, lateral margin and “ball of foot”
– Fibrous septa
= Shock absorber
=Anchors skin
Plantar fascia
(Deep fascia)
• Helps protect deep structures from injury
• Helps support longitudinal archesof the foot
Walking
- Heel
- Lateral border of foot
- Ball of the foot
Fibrous septa
Skin is anchored to fascia with fibrous septa
Plantar aponeurosis
= Thick central part of deep fascia
- Longitudinally arranged
- lots of Bundles of collagen
- Arises from calcaneus
- Distally divides into 5 bands for each of the digits (become continuous with fibrous digital sheaths)
- Reinforced distally by transverse fibres – help keep everything together
Compartments of the Foot
• Vertical intermuscular septa extend from margins of aponeurosis towards 1st and 5th metatarsals
- Central (2) compartment – superficial and deep parts
- Medial compartments
- Lateral compartments
- Interosseous compartments
- Dorsal compartment (extensor hallucis brevis and extensor digitorum brevis)
Muscles of the foot
Layer 1: AFA
- Abductor Hallucis
- Flexor digitorum brevis
- Abductor digiti minimi
Layer 2: 222
• Two tendons =
– Flexor Hallucis longus
– Flexor digitorum longus
• Two muscles =
– Lumbricals
– Quadratus plantae
Layer 3: FAF
- Flexor Hallucis brevis
- Adductor Hallucis (oblique and transverse heads)
- Flexor digiti minimi brevis
Layer 4:
• Dorsal and plantar interossei
Muscles on dorsum of foot
• Intrinisc muscle = in the foot
* Extensor digitorum brevis and Extensor hallucis brevis * both Originate from calcaneus * Aid in extending toes • Extrinsic = muscles and tendons from leg that pass through foot
Plantar Neurovascular Supply
- Tibial nerve and posterior tibial artery divide into medial and lateral plantar nerves and arteries
- Deep to abductor hallucis brevis
- Medial plantar nerve & artery divide into common plantar digital nerves (sensory) and arteries that supply medial 3 and half digits
- Provides sensation to first 3 and a half toes
- Lateral plantar nerve & artery divide into superficial and deep branches
- Superficial supply lateral supplies sensation of 1 and half digits
- Deep branches pass medially
- Artery forms deep plantar arch
- Gives plantar MT arteries
Dorsal Neurovascular Supply
- Anterior tibial artery becomes dorsalis paedis artery
- Continues between EHL extensor hallucis and EDL extesor digitoris longus tendons
- Tarsal arteries
- Dorsal metatarsal arteries – branches
- Communicate with deep plantar arch via perforating branches
Cutaneous innervation of foot (revision) - sensation of the foot
• Saphenous nerve: Branch of femoral. Medial side of foot
• Dorsum of foot – superficial & deep peroneal
• Sole of foot- medial & lateral plantar
• Laterally sural nerve: Branches from tibial and common peroneal nerves
• Heel by
– medial calcaneal branches of tibial nerve
– lateral calcaneal branches of sural nerve
Arches of the foot
• Foot has flexibility due to arrangement of bones, ligaments and tendons
– Shock absorbers
– Springboards
Longitudinal arch of foot – 2 longitudinal arches
• Medial Longitudinal arch higher, formed by calcaneus, talus, navicular, 3 cuneiforms and 3 metatarsals • Lateral longitudinal arch – formed by calcaneus, cuboid, lateral 2 metatarsals Transverse arch of foot formed by cuboid, cuneiforms and bases of metatarsals
Arches of Foot - Factors that maintain and support arches
Passive
• Shape of united bones (above) • Fibrous tissue layers – Plantar aponeurosis Calcaneal to cuboid – Long plantar – Short plantar – Spring
Arches of Foot - Factors that maintain and support arches
Dynamic
- Intrinsic muscles
- FHL and FDL
- Tibialis anterior and Tibialis posterior and peroneus longus = other tendons that support arches of the foot
Venous drainage - deep veins
– paired veins accompany all arteries
2 veins tend to accp=ompany every arter
Venous drainage - surperficial veins
– variable
• Tend to become varicose veins – dilated under skin
• Dorsal and plantar venous network
• Medial marginal vein becomes great saphenous vein – pass behind medial malleous, medial patella,
• Lateral marginal vein becomes short (small) saphenous vein
Lymphatic Drainage
- Medial superficial lymphatic accompany GSV (great saphenous vein) drain in to superficial inguinal lymph nodes (then deep ILN)
- Lateral superficial lymphatic accompany short saphenous to popliteal lymph nodes (then deep lymphatics)
- Deep lymphatics vessels from foot follow main blood vessels carry lymph to deep ILN – inguinal lymph nodes
- Deep ILN drain into external and common iliac, then lumbar lymphatic trunks
Elective -Common foot and ankle disorders
—> things seen in day to day practice
• Ankle osteoarthritis
• Hallux valgus (Bunions)
• 1st MTP joint osteoarthritis (big toe arthritis)
• Claw, hammer and mallet toes (bending of toes)
• Flat foot deformity
• Achilles tendinopathy (sprain in achilles tendon)
Trauma Common foot and ankle disorders
- Achilles tendon rupture
- Sprained ankle
- Ankle fracture
General Common foot and ankle disorders
- Diabetes
* Charcot arthropathy
Primary osteoarthritis
• Primary= as you get older you get degernation of joint due to wear and tear
○ (older, less pain than trauamtic arthritis and better ROM range of movement compared to secondary OA)
Secondary Osteoarthritis
—>pathology precedes arthritis like infections
○ Most commonly post- traumatic
○ Septic arthritis
○ Medical condition (rheumatoid arthritis, inflammatory arthropathy)
○ Main problems CF – Pain, stiffness
Degernative joint
- Narrow joint space
- Condyles aren’t as smooth as normal
- Sclerotic margins and cysts
Hallux valgus (bunion)
- More common in women
- Medial deviation of the 1st Metatarsal – big toe faces outwards but metatarsal faces medially
- Lateral deviation of the toe (+/- rotation)
- 1st MT head becomes prominent (erythema, callous, pain)
- Most common complaints - Pain, cosmesis (cosmetic issue), footwear problem
Hallux valgus (bunion) -Degernative changes
- Metatarsals goes medially
* Phalanges go laterally
Bunion casues
Due to abnormal biomechanics in overpronated foot (flatfoot)
• Trauma
• Arthritis
• Metabolic disorders (gout, inflammatory arthropathy)
• Collagen disorders (familial) - especially if child has bunion
• Wearing heels since a young age
• Once present the extrinsic muscles continue to increase the deformity
Bunion treatment
- Splints = don’t really work but pschologically help patient
- Change in foot wear – seperation between great tor and second toe
- Surgery (extensive and very painful)
Hallux ridges OA of 1sr MTP
- OA of the 1st Metatarsophalangeal joint – joint degerantes, narrows, red, bursitis
- Multiple times the body weight passes through this joint when weight bearing
Hallux ridges OA of 1sr MTP
Causes
- idiopathic,
- trauma,
- sepsis,
- metabolic/inflammatory condition
Clinically - Hallux ridges OA of 1sr MTP
- Pain on dorsiflexion of 1st MTPJ
- Compensatory alteration of gait, walking on the lateral border of the foot to off load the medial side – to deal with pain
- Look at how the sole of their shoes are wearing
- Progressive stiffness limiting movement
- Dorsal osteophyte may rub in shoes
- Reduced dorsiflexion of great toe
Toe deformity – claw toe
—> difficult to wear shoes as the rub inside shoes, cause ulcers on joint surface dorsal
* Multiple toes * Hyperextension at MTPJ (metatarsal pharyngeal joint) with flexion at PIPJ (proxiaml interpharyngeal joint) * Corns/blisters - corns on tip, blisters on dorsum * Flexible/rigid
Toe deformity – claw toe
Causes
- tight tendons and ligaments
- Neurological, Cerebral palsy, stroke
- trauma,
- inflammatory arthropathy (RA)
Toe deformity – hammer and mallet toe
- Hammer - Flexion at PIPJ
- Mallet – fixed at DIPJ dorsal interpharyngeal joint
- Normally walk on the nail
- Commonly second toe fi
Toe deformity – hammer and mallet toe
Common causes
- Pressure due to hallux valgu = as big toe moves, second toe moves upwards to compensate
- poor footwear
Flat foot – pes planus
- Collapse of the medial arch
- In children the medial arch is not fully developed (subcutaneous fat) - but a lot of parents want to give an in sole to do something but it doesn’t make a difference
- Normal for child to have flat foot don’t develop arch after age 10
What happens? - excessive stretching of the spring ligament and plantar aponeurosis. The talar head drops, the arch flattens and the midfoot deviates laterally
Flat foot – pes planus
Causes
- Idiopathic
- Injury
- degenerative (tibialis posterior dysfunction)
Flat foot – pes planus
2 types
Flexible – no issue, don’t do anything
Fixed – bony problems in foot, are tarsals fused together
Test for if it is felxible or fixed
• Good up on tiptoes = arch will reform
○ Less likely to need surgert for flat foot
• Other test = dorsiflex big toe and arch will reform (jack’s test) used for children
Tarsal coalition – calcaneum, navicular are completely separate
• Coalitions can’t be fixed with in soles, need commodative insole to fit foot shape
In soles
- Only help to remove the pain
* Don’t visually change foot
Achilles tendinopathy
One of the larger tendons in the lower limb
Withstands stresses from walking and running
Tendinopathy
- Insertional (into calcaneum) – any age group, not always related to activity
- Non-insertional (body of tendon) – Younger age group, active
Achilles tendinopathy
Common causes
Degenerative
Achilles tendinopathy
Clinical features
- Pain and stiffness particularly after inactivity (morning)
- Pain at back of heel (worse with activity)
- Tendon thickening
- Swelling
- Palpable spur (insertional)
Achilles tendinopathy
Treatment
Treatment —> insoles but beware of achilles tendon rupture
Achilles tendon rupture
Aetiology
Occurs at middle age Middle age - Pre-existing tendon pathology
• Mainly middle age men who have been inactive and now want to be active
Aetiology:-
• Deceased perfusion blood supply
• Increased stiffness (reduction in proteoglycans, with decreased water content and increased cross-linking of collagen)
• Decreased collagen turnover and reduced ability to repair
• Calcium deposition in the tendon
Achilles tendon rupture
Features
- Commonly occurs in middle-aged men
- Forceful push-off (jumping, running)
- Fall/slip into a hole suddenly
- Forcefully DF ankle
Achilles tendon rupture
CF clinical features
Partial/Complete Tear – proximal to the calcaneum
CF clinical features – Sudden pain – Being “kicked in the heel” • Sound – pop/snap • Palpable gap • Unable to push-off
Simmonds Thompson test
- Positive when squeezing of the calf muscles fails to elciti planatrflexion (movement) of the foot)
- Test for achilles tendon rupture
Sprained ankle
—> Partial / complete rupture of ligaments around the ankle – more commonly lateral.
Sprained ankle
Causes
- weak muscles / ligaments around the joint
- Neurological, ligamentous
- Proprioception and balance
- Uneven surfaces
Sprained ankle
Treatment
Rehab – wobble boards, yoga boards, trampolines
Ankle sprain with 5th metatarsal avulsion fracture
- Bruising on side of foot
- Can be associated with an avulsion fracture of the 5th metatarsal base due to the pull of Peroneus brevis on its attachment
Child – be wary as this might just be normal in them, examine child properly
Ankle fractures
Common
- Inversion/eversion, internal and external rotation of the joint
- Associated rupture of medial and lateral ligaments of the ankle joint
- Can result in a fracture dislocation of the ankle joint
- If below the distal tibiofibular joint the syndesmosis is intact and the fracture is considered stable
Ankle fractures
Treatment
• Reducing it and pain
Try and return anatomy as close to normal
Diabetes – general conditions
--> Very commonly affects the foot • Infection • Skin breakdown • Peripheral neuropathy resulting in loss of sensation • Peripheral ischaemia
Combination of the above can cause ulceration and other complications of diabetes
Could lead to amputation below the knee
Charcot arthropathy
—> Progressive destruction of the tissues in the foot – bones, joints and soft tissue
* Caused by a combination of peripheral neuropathy, abnormal weightbearing, inflammatory changes, fractures, osteolysis * The patient is commonly unaware of the damage being done due to loss of sensation and there fore contining normal activities exacerbating the damage being caused – thign sjust keep getting worse
Gait
–> pattern of walking
Can have normal and abnormal gait
The phases of the gait cycle
- Heel/initial contact 9heel hits ground first)
- Foot-flat – load - forefoot to the ground
- Midstance – move forward
- Heel-off
- Toe-off (pre-swing)
Stance and swing phases
• 60% Stance
• 40% Swing
Heel stance
Mid stance
Toe off
* Step is one foot = hell down to next heel down * Stride = both feet, so it is two steps
Kinetics- Cause Movement
- Muscles – provide stability and propulsion
* Work both concentrically (shortening – acceleration) and eccentrically (lengthening – deceleration).
Abnormal gait
- Antalgic / painful limp = spend less time on the affected leg, quickly move off it
- High stepping / foot drop (Tibialis anterior dysfunction)
- Spastic – Hemi/diplegia
- Trendelenburg gait Parkinsonian
- Ataxic/broad based/cerebellar
If right leg is hurting – give crutch to painful leg, so your pushing on the crutch instead of on the painful leg
Antalgic
- Limp
- Pain
- Short stance phase on affected leg
- Lack body weight to shift to the affected leg
- Short swing on unaffected leg
- Uneven pattern
High steppage
Foot drop
• Sciatica
• Neuromuscular
Toes point down
Increased hip flexion on affected side to clear the foot
Foot slap = hear the foot go down as the dorsiflexors of foot aren’t working can’t hold it up
Diplegic
Neuromuscular – CP Scissoring – can't abducted Tight muscle groups Ankle – plantar flexed Forefoot – initial contact
Hemiplegic gait
Stroke, cerebral palsy, trauma • Flexed upper limb • Extended lower limb • Short step unaffected leg • Circumduction of the affected leg – swing leg round
Trendelenberg
Hip abductor weakness • Pain, neurology.. • Pelvis drops on the unaffected side in stance • Torso swings to the affected side • Waddling • Bilateral
Look at patient from behind to see pelvis tilt
Parkinson’s
- Neurological
- Difficulty to initiate movement
- Short shuffling steps – patients tend to trip as they can’t lift leg
- Bend forward
- No arm swing
Ataxic
- Cerebellar disorders - Genetic, alcohol, sensory
- Broad based
- Unco-ordinated
- Arms to balance
- Appear ‘drunk’
Extrinsic muscle- function
Eversion
Inversion
Plantarfiexion
Dorsifiexion
Intrinsic muscles - function
Fine motor actions
