Which of the following is an example of foot
The foot and ankle form a complex system which consists of 28 bones, 33 joints, 112 ligaments, controlled by 13 extrinsic and 21 intrinsic muscles. Show The foot is subdivided into the rearfoot, midfoot, and forefoot. It functions as a rigid structure for weight bearing and it can also function as a flexible structure to conform to uneven terrain. The foot and ankle provide various important functions which includes:
The ankle or tibiotalar joint constitutes the junction of the lower leg and foot. The osseous components of the ankle joint include the distal tibia, distal fibula, and talus. The anatomic structures below the ankle joint comprise the foot, which includes:
The talocrural joint is formed between the distal tibia-fibula and the talus, and is commonly known as the ankle joint. The distal and inferior aspect of the tibia – known as the plafond – is connected to the fibula via tibiofibular ligaments forming a strong mortise which articulates with the talar dome distally. It is a hinge joint and allows for dorsiflexion and plantarflexion movements in the sagittal plane. It is also known as the talocalcaneal joint and is formed between the talus and calcaneus.
Also known as transverse tarsal joints or Chopart’s joint. It is an S-shaped joint when viewed from above. It consists of two joints – the Talonavicular Joint and Calcaneocuboid Joint.
Also known as Lisfranc’s joint. This complex divides the midfoot from forefoot. The distal tarsal rows including the three cuneiform bones and cuboid articulate with the base of each metatarsal to form the TMT complex. It is an S-shaped joint and is divided into 3 distinct columns:
The MTP joints are formed between the metatarsal heads and the corresponding bases of the proximal phalanx. The interphalangeal joints of the toes are formed between the phalanges of the toes. Each toe has proximal and distal IP joints except for the great toe which only has one IP joint. JointType of JointPlane of MovementMotionTC joint HingeSagittalDorsiflexion & Plantarflexion ST jointCondyloidMainly transverse Some sagittal Inversion & Eversion Dorsiflexion & Plantarflexion MT jointTN joint - Ball and socket CC joint - Modified saddle Largely in transverse Some sagittal Inversion & Eversion Flexion & Extension TMT jointPlanarMTP joint CondyloidSagittal Some Transverse Flexion & Extension Abduction & Adduction IP jointHingeSagittalFlexion & ExtensionThe tip of the medial malleoli is anterior and superior to the lateral malleoli, which makes its axis oblique to both the sagittal and frontal planes. The axis of rotation is approximately 13°-18° laterally from the frontal plane and at angle of 8°-10° from the transverse plane. Motion in other planes is required (like horizontal and frontal plane) to achieve a complete motion for plantarflexion and dorsiflexion. The reported normal available range for dorsiflexion varies in the literature between 0°-16.5° and 0°-25°, and this changes with weightbearing. The normal range of plantarflexion has been reported to be around 0°- 50°. The axis of the subtalar joint lies about 42° superiorly to the sagittal plane and about 16° to 23° medial to the transverse plane. The literature presents vast ranges of subtalar motion ranging from 5° to 65°. The average ROM for pronation is 5° and 20° for supination. Inversion and eversion ROM has been identified as 30° and 18°, respectively. Total inversion-eversion motion is about 2:1 and a 3:2 ratio of inversion-to-eversion movement. The Midtarsal joint rotates at two axes due to its anatomy, making its motion complex. The longitudinal axis (image 'A' below) lies about 15° superior to the horizontal plane and about 10° medial to the longitudinal plane. The oblique axis (image 'B' below) lies about 52° superior to the horizontal plane and 57° from the midline. The longitudinal axis is close to the subtalar joint axis and the oblique axis is similar to the talocrural joint axis. MT Joint Locking[edit | edit source]An important function of the foot is propulsion of weight during stance phase. This function is made possible by the MT joint locking and unlocking. During heel strike, the foot needs to be flexible in order to adjust to the surface and the MT joint unlocks to provide this flexibility. Later in the gait cycle, the foot then needs to act as a rigid lever to propel the weight of the body forward which is made possible by MT joint locking. During pronation/eversion of the foot, the axis of the TN and CC joints are parallel to each other, making it easier for them to independently move and unlock the MT joint. The axes cross each other during supination/inversion and locks the MT joint making it difficult to move. Blackwood et al concluded that there is increased forefoot movement when the calcaneus is everted. This is consistent with the MT joint locking mechanism. The degree of sagittal motion for each TMT joint is presented below TMT JointDegree of Motion1st1.6o2nd0.6o3rd3.5o4th9.6o5th10.2oThe MTP joints are bi-axial and move in sagittal and transverse planes. MTP joints have a greater sagittal plane movement and very little transverse plane movement. At MTP joints, hyperextension is about 90° and flexion is about 30° to 50°. IP joints are hinge joints which limit motion in one direction. Arthrokinematics refers to the movement of joint surfaces.
Concave-convex rule Roll & glide Talocrural jointFull dorsiflexion10o of plantarflexion and midway between pronation and supinationLimitation of plantarflexion, although clinically dorsiflexion.Limitation is more common. Proximal - Mortise formed by Tibia, tibiofibular ligament and fibulaDistal - Trochlear surface of Talar domeOpposite directionSubtalar jointFull inversionInversion/plantarflexionLimitation of inversion in chronic arthritis. Limitation of eversion in traumatic.Proximal - Anterior, middle and posterior facet of talusDistal – Calcaneal Anterior, middle and posterior talar articular surfaceOpposite directionTalonavicular jointFull supinationMidway between extreme ROMLimitation of dorsiflexion, plantarflexion, adduction and internal rotation.Proximal - Head of TalusDistal - Concavity on Navicular bone for talusSame directionCalcaneocuboid jointFull supinationMidway between extreme ROMLimitation of dorsiflexion, plantarflexion, adduction and internal rotation.Distal - Cuboid is concave during flexion-extension.Calcaneus is concave during adduction-abduction. Proximal - Calcaneus is convex during flexion-extension. Cuboid is convex during adduction-abduction. Flexion-extension = Same direction Gait is made up of repetitive cycles of the stance phase when the foot is on the ground (foot strike, mid stance, and terminal stance) and the swing phase when the foot is in the air. When running, there is an additional phase: the float phase when both feet are off the ground.
The combination of fixed midfoot, slightly flexible Lisfranc joint, and flexible metatarsophalangeal joints create a lever for propulsion during gait. Influence on Kinetic Chain/Gait[edit | edit source]As discussed above with MT joint locking, the transition in the foot from pronation to supination is an important function that assists in adapting to uneven terrain and acting as a rigid lever during push off.
If the foot remains pronated, it would lead to hypermobility of the midfoot and place greater demand on the neuromuscular structures that stabilize the foot and maintain upright stance. Whereas if the foot remains supinated, the midfoot would be hypomobile, which would compromise the ability of the foot to adjust to the terrain and increase demand on surrounding structures to maintain postural stability and balance. Cote et al. concluded that postural stability is affected by foot position in both static and dynamic conditions. Chain reactions occur secondary to the positioning of the foot. In closed chain movements, the following kinetic chain reaction takes place in an over-pronated foot:
In closed chain movement the following kinetic chain reaction takes place in an over-supinated foot:
The arches of the foot provide functions of force absorption, base of support and acts as a rigid lever during gait propulsion. The medial longitudinal arch, lateral longitudinal arch and transverse arch are the 3 arches that compromise arches of foot. It is the longest and highest of all the arches. Bony components of MLA include the calcaneus, talus, navicular, the three cuneiform bones and the first 3 metatarsals. The arch consists of two pillars: the anterior and posterior pillars. The anterior pillar consists of the head of first 3 metatarsal heads and the posterior pillar consists of the tuberosity of the calcaneus. The plantar aponeurosis forms the supporting beam connecting the two pillars. The apex of the MLA is the superior articular surface of talus. In addition to the plantar aponeurosis the MLA is also supported by the spring ligament and the deltoid ligament. The Tibialis anterior and posterior muscles play an important role in raising the medial border of the arch, whereas Flexor hallucis longus acts as bowstring. Lateral Longitudinal Arch (LLA)[edit | edit source]It is the lowest arch and comprises of the calcaneus, cuboid, fourth & fifth metatarsal as its bony component. Like the Medial Longitudinal Arch (MLA) the posterior pillar consists of the tuberosity of the calcaneus. The anterior pillar is formed by the metatarsal heads of 4th and 5th metatarsals. The plantar aponeurosis, long & short plantar ligaments provides support to the LLA. The Peroneus longus tendon plays an important role in maintaining the lateral border of the arch. It is concave in non-weight bearing and runs medial to lateral in the midtarsal and tarsometatarsal area. The bony component of the arch consists of the metatarsal heads, cuboids and 3 cuneiform bones. The medial and lateral pillars of the arch is formed by the medial and lateral longitudinal arch respectively. The arch is maintained by the Posterior tibialis tendon and the Peroneus longus tendon which cross the plantar surface from medial to lateral and lateral to medial respectively. The plantar aponeurosis acts similarly to a windlass mechanism. A windlass is typically a horizontal cylinder that rotates with a crank or belt on a chain or rope to pull heavy objects. The common use of a windlass is in pulling the anchor of the ship known as an anchor windlass. This mechanism can be seen in the foot. When the MTP joints are hyperextended, the plantar aponeurosis becomes taut as it is wrapped around the MTP joints. This actions brings the metatarsal and tarsal bones together converting it into a rigid structure and eventually rising the longitudinal arches. This function is important in providing a rigid lever for gait propulsion during push off. The foot requires sufficient mobility and stability for all of its functions. Mobility is necessary for absorbing the ground reaction force of the body. Subtalar pronation has a shock absorbing effect during initial heel contact. Pronation is also necessary to enable rotation of the leg and to absorb the impact of this rotation. Subtalar pronation plays a role in shock absorption through eccentric control of the supinators. On the other side, the joint of Chopart becomes unlocked so that the forefoot can stay loose and flexible. In midstance, the foot needs mobility to adapt to variation in surfaces. Foot stability is necessary to provide a stable base for the body. The foot needs the capacity to bear body weight and act as a stable lever to propel the body forward. This function requires pronation control of the subtalar joint. Normal foot function provides the foot with the capacity to transform at the right time from a mobile adapter to a rigid lever. The foot needs sufficient mobility to move into all the positions of the gait cycle while maintaining mobility and stability. Physiological mobility is essential; if mobility was too large, the foot would not have the capacity to be stable. When this condition is fulfilled, the joint can support standing in the stable maximally close packed position. When the normal transition of the two functions isn’t normal, many overload injuries can be observed in the foot, leg but also in the lower back. Therefore the three phases of ground contact have to fall in the normal time interval, otherwise some compensation mechanisms (example: genu recurvatum in cases of reduced dorsiflexion) will be used, which cause overuse syndromes. (Example: chondromalacia, shin-splints) In the transition from midstance to propulsion phase, the mechanisms often fail. The transition from eversion to inversion is facilitated by the tibialis posterior muscle. The muscle is stretched like a spring and potential energy is stored. At the end of the midstance, the muscle passes from eccentric to concentric work and the energy is released. The tibialis posterior muscle then causes abduction and dorsiflexion of the caput tali in which the hindquarter is everted. At the same time, the peroneus longus muscle, at the end of the midstance, will draw the forefoot with a plantar flexion of the first toe. This is how the forefoot becomes stable. When the forefoot moves in the propulsion phase, the windlass phenomena starts. When the dorsiflexion of the metatarsophalangeal joints begins, the plantar fascia undergoes stress.The calcaneus becomes vertical and teared in inversion. Like this, the hindquarter rests in inversion in the unwinding of the forefoot. When there are some abnormalities in the normal gait cycle of functions of the body, some functional orthosis can be used. This orthosis have the capacity to correct the biomechanical function of the foot. In contrast, insoles only support the arch of the foot. Reduced or limited mobility in the lower limbs can be caused by a articular limitation. In these cases some classic mobilizations or mobilizations according to manual therapy can be applied. When the cause is a muscle shortening some stretching can be prescribed. Also, good (running) shoes are indicated. What is an example of foot?Foot refers to the single unit of measurement. For example, a cat is 1 foot tall. “Feet” is its plural alternative. For example, the height of a child is 3 feet.
What is a foot in poetry example?The two most common three-syllable poetic feet are the anapest and the dactyl. In an anapest, the first two syllables are unstressed and the final syllable of the foot is stressed (da-da-DUM). An example is the word overcome. A dactyl is the opposite, with the first syllable stressed and the other two unstressed.
What are the types of foot in poetry?The standard types of feet in English poetry are the iamb, trochee, dactyl, anapest, spondee, and pyrrhic (two unstressed syllables). Check out our Learn area, where we have separate offerings for children, teens, adults, and educators.
How many foot types are there?The length, shape and alignment of your toes largely dictates what type of feet you have. Research suggests there are at least 9 different foot types. These are: Egyptian, Greek, Roman, Celtic, Germanic, Peasant, Square, Stretched and Simian.
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