structure and function of the foot Flashcards
What is the Hallux and in regards to anatomical aspect how would you describe its position
The Hallux is the big toe and it would be described as being positioned on the medial aspect of the foot as it is toward the mid line of the body/ on the inside of the foot
The Hallux is the only toe which consists of 2 phalanges every other toe has three.
Describe the ankle joint/Talocrural in detail
The TRUE Ankle Joint also known as the Talocrural Joint and is a Synovial Joint located in the lower limb. It is made up of the:
Tibia (MEDIAL/ Load Bearing)
Fibula (Lateral)
Talus (Articulates with Tibia/Fibula to form Hinge Joint)
The Ankle joint is often described as Tenon and Mortise Joint (Tibia, Fibula form a squared of notch shape in which the body of the Talus fits acting as the Tenon.
Describe the movement of the ankle joint
The ankle is a Hinge joint which allows triplanar movement across simultaneous planes of movement (Predominantly in the Sagital Plane Up and Down)
The main movement that occur at the ankle joint are Plantar Flexion and Dorsiflexion although the joint also allows for inversion and eversion.
Plantar Flexion also referred to as extension of the ankle is when the plantar surface of the foot is pushed further away from the shin (POINTING OF THE TOES)
Dorsi Flexion is when the Dorsal (Superior/on top/above/top of) surface of the foot is drawn closer to the shin.
Inversion is when the sole of the foot is tilted inwards toward the midline of the body
Eversion is when the sole of the foot is tilted outwards away from the midline of the body
Name the bones of the foot from a Medial aspect
Fibula (Medial)
Tibia (Lateral)
Talus (articulates with fibula/Tibia)
Navicular (In front of the talus on the medial side)
Cuboid (Next to the Navicular on the lateral side)
Cuneiforms (3 bones in front of the navicular)
Metatarsals (5 bones labelled 1 through to 5 starting with the hallux)
Phalanges (14 bones that make up the toes, Hallux has 2 every other toe has 3 Phalanges)
Calcaneus (Largest bone of the foot situated beneath the Talus/Heel Bone)
Describe the Subtalar Joint in detail
Clue JC SM AND FL
The Subtalar Joint is an articulation between the Talus (Superior sits above) and the Calcaneus (Inferior sits below)
The subtalar joint allows for subtalar inversion and eversion and is enclosed by a joint capsule lined by synovial membrane and strengthened by a fiborous layer.
Detail the ligaments on the Medial aspect which stabilize the subtalar joint
Ligaments on the Medial aspect of the subtalar joint are known as the MCL Ligaments or the Deltoid ligaments (Deltoid because of their triangle shape)
Deltoid ligamnets consist of:
- Posterior Tibiotalar Ligament (The back of the Tibia connecting to the Talas)
- Tibiocalcaneal Ligament (The Tibia connecting to the Calcaneous)
- Tibionavicular Ligament (The Tibia connecting to the Navicular)
- Anterior Tibitalar Ligament ( The front of the Tibia connecting to the Talas)
All these ligaments form a triangle type shape on diagram
These ligaments protect against eversion (movement away from the mid line of the body) and give about a 10% range of motion. They are stronger than the anterior ligaments.
Detail the ligaments on the Lateral aspect which stabilize the Subtalar Joint
Clue they all end in Fibular
Ligaments on the Lateral aspect of the subtalar joint are known as the LCL ligaments
Posterior/Anterior TaloFibular
Calcaneofibular
Lateral Ligaments consist of:
- Posterior Talofibular ligament (The back of the Fibula connecting to the Talas)
- Calcaneofibular Ligament (Fibula connecting to the Calcaneus)
- Anterior Talofibular ligament (Back of the Fibula connecting to the Talas
These ligaments protect against Inversion, movement of the plantar surface toward the mid line of the body. These ligaments give around a 20% range of motion limited by the weaker LCL ligaments.
Describe the various functions of the foot
There are 4
- Supporting body weight
- Providing Balance
- Shock Absorption
- Transferring ground reaction forces
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Describe the Hindfoot
- Most Posterior aspect of the foot (Back part)
- Consists of two of the seven tarsal bones these being the Talus and Calcaneus
- The articulation between the Talus and Calcaneus is referred to as the Subtalar joint
Describe the Mid Foot
Clue Junction mid/hind and what joints it consists of
- The Mid Foot consists of 5 of the 7 Tarsal bones, the Navicular, Cuboid and all 3 Cuneiform’s (Medial, Middle, Lateral)
- The junction between the hind and mid foot is termed the Chopart’s joint, which includes the Talonavicular and Calcaneocuboid joints.
Describe the Forefoot
- Most anterior aspect of the foot (Front of the foot)
- Consists of Metatarsals, Phalanges and Sesamoid bones
- 1 Metatarsal and 3 Phalanges for each toe except the Hallux which only has 2 Phalanges
- The articulation between the Forefoot and the Mid foot is known as the Lisfranc joint
Describe the Miditarsal Joint
Don’t forget to mention the articulations between the bones and how the joint is formed
- It consists of two joints, these being the Talonavicular and the Calcaneocuboid joint
- Talonavicular Joint is formed between the anterior head of the talus and the concavity of the Navicular It share a joint capsule with the two Talocalcaneal articulations
- Calcaneocuboid joint is formed between the anterior facet of the Calcaneous and the posterier of the Cuboid
- Very little movement occurs at this joint
Which bones form part of the Medial Longitudinal arch of the foot
Calcneus
Talus
Navicular
All 3 Cuneiforms
1,2,3 Metatarsals
Describe the arch of the foot
The arches of the foot are formed by the Tarsal and Metatarsal bones.
The Tarsal and Metatarsal bones form two longitudinal arches (Medial + Lateral) as well as a Single Transverse arch
Which bones of the foot form the Lateral Longitudinal Arch
The Lateral Longitudunal arch (much flatter than the medial) is formed by:
Calcaneus
Cuboid
Fourth and Fifth Metatarsals
Describe the charecteristics of a Planus Foot
OP VAL H and VAR F
Planus feet are low arched and associated with over pronation (Flat foot) They tend to have a Valgus Hindfoot (turned away from the midline of the body) and or Varus Forefoot (turned inwards toward midline) and are considered a risk factor in the development of overuse injuries
Low Arch
Over Pronation
Valgus Hindfoot (turned away from midline of the body)
Describe the charecteristics of a Cavus Foot
What does it doe to the forefoot
Cavus feet are high arched and associated with hammer toes and claw toe deformities. The high arch causes more pressure to be put on the forefoot on through the metatarsals
Describe the characteristics of Rectus foot
Rectus feet are considered to well aligned hindfoot and forefoot with a moderate foot arch