PODI3113 EXAM

Hindfoot

Includes Talus (connects to the leg) and Calcaneus (heel bone).

Midfoot bones

Includes Navicular, Cuboid, and three Cuneiforms (medial, intermediate, lateral).

Forefoot

Composed of 5 Metatarsals and 14 Phalanges (toes).

Talocrural (Ankle) Joint

Formed by the tibia, fibula, and talus; responsible for up (dorsiflexion) and down (plantarflexion) movement.

Subtalar Joint

Between the talus and calcaneus; allows for side-to-side tilting (inversion and eversion).

Metatarsophalangeal (MTP) Joints

Connect the metatarsals to the toes.

Lateral Complex

Includes the ATFL, CFL, and PTFL; often strained in ankle sprains.

Deltoid Ligament

A strong, fan-shaped ligament on the medial (inner) side.

Plantar Fascia

The longest ligament in the foot, supporting the arch.

Achilles Tendon

The body's strongest tendon; connects calf muscles to the heel.

Tibialis Posterior Tendon

Crucial for supporting the foot's arch.

Peroneal Tendons

Run behind the lateral ankle to help turn the foot outward.

Sciatic Nerve

The largest nerve in the body; bifurcates above the knee into the Tibial and Common Fibular nerves.

Tibial Nerve

Supplies the posterior compartment (calf muscles) and travels behind the medial malleolus into the sole of the foot.

Common Fibular (Peroneal) Nerve

Divided into Deep Fibular Nerve and Superficial Fibular Nerve.

Deep Fibular Nerve

Supplies innervation to the anterior compartment (dorsiflexors) and the skin between the first and second toes.

Superficial Fibular Nerve

Supplies innervation the lateral compartment (evertors) and most of the skin on the top (dorsum) of the foot.

Saphenous Nerve

A purely sensory branch of the femoral nerve that supplies the medial aspect of the leg and ankle.

Popliteal Artery

The continuation of the femoral artery behind the knee; divides into the anterior and posterior tibial arteries.

Anterior Tibial Artery

Supplies the anterior muscles and continues onto the top of the foot as the Dorsalis Pedis artery.

Posterior Tibial Artery

Supplies the posterior leg and enters the sole of the foot to form the medial and lateral plantar arteries.

Fibular (Peroneal) Artery

A branch of the posterior tibial artery that supplies the lateral compartment of the leg.

Deep Veins

Generally follow the path of the arteries and drain into the Popliteal Vein.

Great Saphenous Vein

Drains blood from the dorsal venous arch of the foot toward the thigh.

Sesamoid

A bony structure that is round with bone cortex & cancellous bone embedded in a tendon.

Ossicle

An anatomical variant that has no known function and is free-floating.

Primary Ossification Centre

Where the bone first forms, visible at birth.

Secondary Ossification Centre

Additional sites of bone formation in a single bone with its own blood supply.

Epiphyseal plate

Contains hyaline cartilage

Tarsal bones ossification centres

Have 1 ossification centre (main body), except for the calcaneus (it has 2; main body and posterior process)

Sever's disease

Inflammation of the posterior epiphysial region

Metatarsals ossification centres

Have 2 centres: 1 for the shaft and 1 at the base of the 1st and heads of 2-5

Phalanges ossification centres

Have 2: 1 at the shaft and 1 at the base

Sever's & Osgood Schlatters

Both are inflammation

Osgood-Schlatter's disease

Occurs in the anterior part of the tibia (tibial tuberosity) where the quadriceps tendon attaches to

High risk activities for Sever's and Osgood-Schlatter's

Children who play soccer, football, and volleyball

MSK pathology

Linked with Neurodevelopmental pathology -> ADHD 70% increase in getting the disease

Imaging Characteristics of Sever's and Osgood-Schlatter's

Small, smooth and round

Imaging Characteristics of ossicles and sesamoids

Has an apparent cortical bone region

Hallucal Sesamoids

Location: plantar aspect of the first metatarsal head and the lateral slips of the flexor hallucis longus tendon 100% prevalence (6.65% bipartite and 0.16% multipartite)

Hallucal Interphalangeal sesamoids

Location: on the plantar aspect of the interphalangeal joint of the first digit of the foot (Hallux) Prevalence 2-13%

Lesser Metatarsal Sesamoids

Location: Plantar aspect of the metatarsal heads (2-5). Prevalence: Second: 0.4-0.315%, Third: 0.2-0.4%, Fourth: 0.1-0.72%, Fifth: 4.3-9.06%

Os Peroneneum

Location: at the cuboid tunnel near the calcaneocuboid joint, embedded in the peroneus longus tendon Prevalence 26%-28%

Os Trigonum

Location: posterior to the talus. Prevalence 7-25%

Os Intermetatarseum

Location: between the first and second metatarsal (lisfranc joint) Prevalence 1-13%

Os Naviculare

Prevalence: 2-14%. Types: type 1: os tibiale, free floating(20%); Type 2: os tibiale externum, linked by a cartilaginous link to the body of the navicular (50%); type 3: naviculare secundarium, the ossicle fused with bone to the navicular body (30%)

Os Vesalianum

Location: proximal to the base of the 5th metatarsal, within the tendon of the peroneus brevis. Prevalence 0.1-1%. can be a sesamoid or ossiclele

Os Supranaviculare

Other names: os talonaviculares dorsalis, talonavicular ossicle, Pirries bone, dorsal to the talonavicular joint. Prevalence: 1-3.5%

Os Supratalare

Location: over the ridge of the head/neck of the talus, may be fused with the talus or free-floating. Prevalence: 0.2-2.4%

Os Talotibiale

Location: anterior to the tibiotalar joint. Can cause ankle impingement syndrome and its prevalence is 0.5%

Os Calcaneus Secundarium

Location: adjacent to the anterior calcaneal process. Prevalence 0.6-7%

Os Subfibulare

Location: inferior to the lateral malleolus or fibula. Prevalence 1%

Os subtibiale

Location: inferior to the medial malleolus or tibia. Prevalence of 1.2%

Pathological conditions

May result in neighbouring bones fracturing or ossicle fracture only

Hallucal sesamoids fracture

Can be fractured from large force trauma (falling from great heights)

Os trigonum fracture

Can be caused by forced plantar flexion

Os peroneum fracture

Can be caused by inversion injury and its proximal migration -> peroneus longus tendon tear

Os subfibulare fracture

Can lead to anterior talofibular ligament (ATFL) from trauma

Sesamoiditis

Chronic pain (specifically in hallucal sesamoids) caused by stress/fracture/OA/osteonecrosis/tendonitis/capsular inflammation

Infection

Osteomyelitis, the sesamoids and ossicles are infected -> secondary infection

Dislocations

Hyperextension of 1st MTPJ -> dislocation of proximal phalanx -> hallucal sesamoids dislocated laterally.

Degenerative Diseases

Due to OA (hallucal sesamoids), symptoms: loss of joint space, osteophyte formation, sclerosis

Ankle impingement

Posterior ankle pain associated with os trigonum degenerative changes, anterior ankle impingement may be associated with degenerative changes to os talotibiale

Clinical pearls

Often recognised as secondary findings, ossicle/sesamoid injury can cause injuries to other parts of the foot

Ossicles and sesamoids

Often asymptomatic but are sometimes associated with local pain or can be mistaken for pathological conditions (fractures)

Ossicle/sesamoid diagnosis

Gold standard: 2 views on radiographic imaging

Incidence of accessory ossicles in the foot

18-36% of the general population

Lymph capillaries

Absent in: bone marrow, CNS, tissues that lack blood flow (e.g. epidermis, cornea)

Right Lymphatic Duct

Drains the upper arm and right side of the head and thorax

Thoracic duct

Arises from the cisterna chyli and drains the rest of the body

Lower Limb Lymph Drainage

Starts from the femoral triangle; Major groups: superficial vessels and nodes + deep vessels and nodes

Superficial lymphatic vessel (Medial)

Follows the great saphenous vein and is larger

Superficial lymphatic vessel (Lateral)

Follows the small saphenous vein and is smaller

Deep Lymphatic vessels

Accompany the deep veins; Sets: anterior tibial lymph vessel, posterior tibial lymph vessel, peroneal lymph vessel

Popliteal Lymph Nodes

Embedded in the fat of the popliteal fossa; Small and few

Inguinal Lymph Nodes

Superficial inguinal glands: below the inguinal ligament and forms a chain

Obturator nerve

One of the nerves supplying the lower limb

Femoral nerve

One of the nerves supplying the lower limb

Common fibular/peroneal nerve

Originates from the sciatic nerve

Sural nerve

From the tibial nerve and common peroneal nerve; Travels with small saphenous vein

Medial plantar nerve

Largest and most anterior terminating branch of tibial nerve

Lateral plantar nerve

Lies between flexor digitorum brevis and quadratus plantae

Medial calcaneal nerve

Innervates medial and posterior parts of the heel

Lateral calcaneal nerve

Innervates the lateral and posterior parts of the heel

Intermetatarsal Neuroma

Condition where the nerves are enlarged due to friction or sustained compression of a nerve for a long time

Common iliac artery

Branches into internal iliac and external iliac arteries

Femoral artery

Branches include medial circumflex, lateral circumflex, profunda, and 4 perforating branches

Peroneal artery

Branches from the posterior tibial artery

Cruciate Anastomoses

Arterial network located around the proximal femur or hip joint.

Inferior gluteal artery

One of the four main arteries in the cruciate anastomoses.

Lateral and medial circumflex femoral arteries

Two of the four main arteries in the cruciate anastomoses.

First perforating artery of the profunda femoris artery

One of the four main arteries in the cruciate anastomoses.

Anastomotic branch of the posterior branch of the obturator artery

One of the four main arteries in the cruciate anastomoses.

Obturator artery branch

Supplies the artery of the head of the femur.

Nutrient artery of the femoral shaft

Only reaches the head in adults after epiphysis fusion.

Retinacular arteries of the femoral neck

Arteries that arise from the cruciate anastomoses.

Deep Penetrating Arteries

Starts from the femoral artery and continues to the perforating artery.

Periarticular Genicular Anastomosis

Arteries that surround the knee and provide collateral circulation during full knee flexion.

Superior lateral genicular artery

One of the branches of the popliteal artery in the knee.

Superior medial genicular artery

One of the branches of the popliteal artery in the knee.