Module 12: Ankle/Foot (1)

Three bands of LCL complex?

-Anterior Talofibular ligament -Posterior calcaneofibular ligament -Posterior talofibular ligament

Because of its vertical orientation, it is most stressed if the ankle is in dorsiflexion & inversersion, which ligament is this? What helps to reinforce this ligament? How does the Posterior talofibular ligament run?

-Calcaneofibular ligament (since the talocrural joint is in a closed-packed position in dorsiflexion, the ankle has osseous support in a dorsiflexed position to help prevent excessive damage to this ligament) -inferior band of superior peroneal retinaculum lies almost parallel to help reinforce -Runs horizontally, usually last ligament to be torn ; most likely requires ankle dislocation to be torn

What motions do the three bands of LCL check? Which ligament is usually sprained when you roll your ankle; how does it run? If ruptured what instability is present?

-Check inversion and/or supination of ankle & talus ; also position they can be torn in -Anterior talofibular ligament; runs in horizontal direction (weakest, stretched more in plantarflexion,medial rotation & inversion) -Anterolateral instability

Medial Collateral Ligament and Lateral Collateral Ligaments are purposed to maintain good contact between the talus & mortise. What is another name for MCL? What are its attachments?How is it most commonly injured/motions that it resists?

-Deltoid ligament. (not common to injure) -Originate at medial malleous &insert onto navicular, talus & calcaneous. -Resists: eversion and/or pronating the ankle & talus (very strong ligament)

Dysfunction of the Tarsometatarsal Joint: Forefoot Varus

-Driven by excessive pronation of hindfoot, then forefoot must supinate -foot remains in this position then soft tissues adapt & cause fixed supiantion twist/forefoot varus

Brain Check: The tarsometatarsal Joints are_______synovial joints. The ______ metatarsal joint is set more posteriorly than the other tarsometatarsal joints. T or F: The first metatarsal joint exists between the base of the first metatarsal and the middle cuneiform. Which metatarsals articulate with the cuboid? The ___________ligament prevents excessive motion and splaying of the metatarsal heads. Which of the following tarsal bones articulate with the second metatarsal?

-Plane synovial joints -Second metatarsal joint -FALSE. Medial cuneiform -4th and 5th -Deep transverse metatarsal -Second metatarsal articulates with mortise formed by middle cuneiform & the sides of the medial & lateral cuneiform bones

Proximal Tibiofibular joint is what type of joint? Tibial facet is ? Fibular facet is? How is the joint oriented?

-Synovial joint -Tibial facet slightly convex; fibular facet is slightly concave -oriented at 45° angle running from a posteromedial position to anterolateral position

Brain Check: T or F: Small motions at the distal tib-fib joint lead to larger motions at the proximal tib-fib joint. This is why the proximal joint is a synovial joint, but the distal joint is a less mobile syndesmotic joint. Primary limits to talocrural plantarflexion ? What is the necessary amount of ankle dorsiflexion ROM necessary for ambulation without deviation? T or F: Ankle plantarflexion is considered to the be closed packed position for the talocrural joint

-TRUE -Extensor halliculs longus, Extensor Digitorum & Anterioir TIb -10 degrees -False; dorsiflexion is

Brain Check: In the stance phase of gait, as the tibia moves forward over the foot (forward limb progression), the tibia rolls _____ and glides _____. In open-kinetic chain ankle plantarflexion, the _____ moves on the ______. In open-kinetic chain dorsiflexion, rolling of the osseous structure occurs _____, while gliding occurs _____.

-anteriorly;anteriorly -body of talus; mortise -anteriorly; posteriorly

Talonavicular joint is a ______ joint. Which bone surface is convex/concave? What are the boundaries of the joint capsule?

-ball and socket -End of Talus is convex in all directions & navicular is concave in all directions Joint Capsule: Inferior portion: Spring ligament Medial portion: Deltoid ligament Lateral Portion: Bifurcate ligament

Talocrural joint refers to articulation of ? Type of joint? Motion primarily produced?

-body of talus in the mortise or articulation btw distal surface of fibula&tibia -synovial hinge joint; oblique axis with 1 DOF -dorsiflexion/plantarflexion

More about Mortise: What shape does distal tibia & fibula create? Posterior extension of distal tibia is sometimes called? Mortise at the ankle is adjustable based on?

-concave surface that convex talus sits in ; fibula extends more distally than tibia & posterior margin of tibia extends more distally than anterior margin -Posterior malleolus -based on mobility proximal & distal tibiofibular joints (fusion can affect ROM/Fucntion of ankle foot complex)

Brain Check: The moving _____on the larger _____facet of the talus must undergo a greater displacement than the opposite side during talocrural dorsiflexion. T or F: The increased pressure on the body of the talus due to the fit of the talocrural joints makes this joint prone to degenerative osteoarthritis. The primary limitation to talocrural dorsiflexion with the knee in extension is the _____. Normal ankle ROM is________ degrees of dorsiflexion and _____degrees of plantarflexion.

-distal fibula; lateral -False; ability of ankle to distribute weight-bearing forces combined w/mechanical properties of tibotalar articular cartilage reduces risk of osteo -Gastrocnemius -20 dorsi; 50 planti

*The first ray (first tarsometatarsal joint) has the largest ROM, and the axis of motion is inclined to produce ? Fifth ray moves around an axis opposite of first ray, motions that occur with dorsiflexion are? Plantarflexion are?

-dorsiflexion of first ray, also includes inversion &adduction -planterfelxion of first ray includes abduction &eversion 5th Ray: Dorsiflexion: eversion & abduction PLantarfelxion: inversion & adduction (2nd ray moves like 1st ray; 4th ray moves like 5th ray. 3rd ray only produce plantarflexion/dorsiflexion)

What is the Transverse Tarsal Joint formed by and what shape does it create?

-formed by talonavicular joint and calcaneocuboid joint; it creates an "S" shape when you look at dorsal surface of foot -divides hindfoot from midfoot

What is the primary contribution to pronation & supination of the talocrural joint?

-plantarflexion & dorsiflexion However, as the foot is brought into dorsiflexion, the oblique axis of orientation also brings the foot slightly lateral to the leg, and it turns the foot away from midline (pronation). Likewise, plantarflexion of the foot tends to bring the foot towards midline and medial to the tibia.

Calcaneocuboid joint create a _____ joint. What type of motion does this relatively fixed joint produce?

-saddle joint, reciprocally oriented convex/concave in different directions -twisting motion @midfoot & hindfoot (critical for function)

Distal Tibiofibular joint is what type of joint? Which surface is convex/concave? Is there a joint capsule?

-syndesmosis -Distal tibia is concave & distal fibula is convex ; no joint capsule

Purposes of Transverse Tarsal joint? (2)

1. Add to the total range of motion of the subtalar joint for pronation and supination 2. Compensate the forefoot for hindfoot positioning; serves to keep forefoot in contact with the ground

Supination twist: occurs as a result of excessive hindfoot pronation, or inability of transverse tarsal joint to meet supination demands. Describe what happens...

1. Extreme pronation at subtalar joint is accompanied by adduction&plantarflexion of the hed of talus 2. eversion of calcaneus 3. GRF pushes 1st & 2nd metatarsals into dorsiflexion 4. toe flexors pull 4th&5th metatarsals back down to ground 5. 1st &2nd rays will invert, producing a supiantion or inversion twist of tarsometatarsal joints

Body of talus has three articular surfaces that fit nicely with the mortise, what are they articulating with? How and why does the joint "lock out"? What does the change in width mean?

1. Lateral facet --> fibula 2. Medial facet --> tibia 3. Trochlear surface --> inferior tibia Medial facet is way smaller than lateral. -Body of talus is larger anteriorly than posteriorly; so joint locks when anterior portion is in contact with mortise ; -change in width means talocrural joint is more stable with DORSIFLEXION

Gait requirements for both inversion and eversion is? What is the rigid position of the foot and purpose; what is the shock absorption position?

5° in both inversion and eversion. The most important thing is that the subject can move through an arc of inversion and eversion to meet the demands for gait. This is how you will lock and unlock the foot to absorb shock. * Supinated rigid foot is needed for push-off phase of gait & pronated position allows for a softer load transmission in loading phase of gait

What is the axis of motion at the talocrural joint? What gives the axis it's oblique orientation?

Axis of motion: runs from lateral malleolus through talus to medial malleolus Oreintation: lateral malleolus is more distal and posterior to medial

Pes Planus

Calcaneal angle of inclination values between 10°-20° Calcaneus stuck in eversion. Talus PAds (plantarflexion & adduction) dragging navicular plantarly You see calacnaeal valgus position with dropped medial arch of foot

Pes Cavus

Calcaneal inclination angle is above 30° Calcaneus is inverted. Talus DAbs (dorsiflexes/Abducts) which brings the navicular dorsally to create a high medial arh

Define Calcaneovalgus vs Calcaneovarus

Calcaneovalgus: increase in medial angle between calcaneous & posterior leg Calcaneovarus: decrease in medial angle btw calcaneous and posterior leg

What are the primary functions of the prominent ligaments of the subtalar joint? (3)

Cervical Ligament (strongest): Joint neck of talus with neck of calcaneus ; limits the extremes of all motions (esp. inversion) Calcaneofibular: limits excessive inversion Tibiocalcaneal fibers of deltoid ligament: limts excessive eversion

What ligaments/structures are taut in Dorsiflexion? What ligaments are taut in plantarflexion?

Dorsiflexion: Achilles tendon, posterior capsule, posterior calcaneofibular ligament PLantarflexion: Anterior capsule & anterior talofibular ligament

What 2 axes of motion does the Transverse Tarsal joint have? What motions are they most likely to produce?

Longitudinal axis and Oblique axis -Longitudinal axis is very close to A-P axis--> produces inversion/eversion motions -Oblique axis is half-way between Z&Y axes and Z & X axes--> results in abduction/adduction as well as dorsiflexion/plantarflexion

What is the importance of the ligaments at the distal tibiofibular joint? Name the ligaments. What is a high ankle sprain? Which bone allows for mobility of the joint?

NO joint capsule, so ligament attachments allow stability at the joint & mobility to allow for widening & adjustment of the mortise width Anterior & Posterior tibiofibular ligaments, Interosseous Membrane High Ankle Sprain: Forcible lateral rotation of mortise causing talus to translate fibula away 4rm tibia Fibula allows for mobility, since there isn't much weight-bearing tht occurs @the fibula (no more than 10%).

Weight-Bearing Hindfoot Pronation and Transverse Tarsal Joint Motion

Pronation occuring at subtala joint through medial rotation of tibia, transverse tarsal joint is free to: 1. supinate slightly to maintain relatively fixed position of forefoot (standing on one leg example) 2. pronate slightly (occurs in normal bilateral stance) 3. supinate alot to maintain appropiate weight-bearing of forefoot segment (uneven terrain)

II, there is a phase of gait called Loading Response, and it occurs right after your foot goes flat onto the ground. Your limb accepts your body weight, producing knee flexion and slight tibial internal rotation. This tibial internal rotation causes the talus to adduct, or medially rotate. What motion happens with this talar position?

Pronation! So Lateral rotation of weightbearing leg produces supination on subtalar joint.

In an open-kinetic chain, the calcaneus is able to move freely into these coupled motions What are the coupled motions for Pronation & Supiantion? This is most easily when you have the patient lay?

Pronation: Abduction, Eversion & Dorsiflex Supination: Adduction, Inversion: Plantarflex Prone, so the calcaneous can be moved passively

Explain what happens in the subtalar joint during weightbearing for pronation and supination to occur.

Pronation: Calcaneous can still evert, but it needs the talar joint to adduct & plantarflex then the leg/tibiofibular jt. will IR to cause pronation Supination: Calcaneous will inversion, Talar abduction, dorsiflexion & Tibifibular ER

Name the 3 general cardinal plane motions that make up "Pronation in Non-WB?" Supination in Non-WB?

Pronation: Dorsiflexion, Abduction & Eversion (DAbE) Supination: Plantarflexion, Adduction, Inversion (PAdI)

Subtalar joint: What main components make up pronation/supination? What is the axis degree?

Pronation: Eversion+Abduction + Dorsiflexion Supiantion: Inversion+ Adduction + Plantarflexion 42 degree axis; lies halfway between vertical axis & A-P axis; it's almost perpendicular to X-axis so jt. is not contributing to dorsiflexion/plantarflexion

What does the alternating articulation pattern of the subtalar joint allow? What is the name of the groove between the facets?

Subtalar joint moves in the coronal plane about an A-P axis which reduces the rotational forces at the talocrural jt. & distal tibia. -Tarsal canal or Sinus Tarsi; it creates two different joint capsules (Posterior articulation has a capsule & AF+MF+Talus have their own capsule)

What is subtalar neutral? Calcaneal inversion and eversion are measured between the posterior midline of the leg and the posterior calcaneus. Range of inversion/eversion is proportional to? Inversion angle of ? Everison angle of? How much eversion should a standing subject have?

Subtalar neutral refers to a position where the talus is centrally located in the mortise. -supination/pronation -inversion angle of 20°-30°, and an eversion angle of 5°-10°. In standing, subjects should have about 3.5° of eversion.

Tibia follows the ....

Talus Therefore, if the talus is moving into medial rotation , or adduction, then the tibia will medially rotate as well.

Surfaces of the subtalar joint allow for dampening of rotational forces that have to occur when the foot is in contact with the ground. Describe the osseous articulations of the joint. Facets on Talus & Calcaneous? Which articulation receives most force?

Talus: Concave Posterior Facet, Convex Anterior and Medial Facets Calcaneous: Convex Posterior Facet; Concave AF & MF Posterior articulation receives 75% of forces.

Brain Check: Below is a sequence of events. Place them in the order they should occur, number 1 being the first item. Select the step number from the drop down next to each item. Items to order: 1. The concave tibiofibular segment slides forward on the trochlear surface of the talus. 2. Tibia rotates over the talus. 3. The wider anterior portion of the talus wedges into the mortise. 4. The tibia and fibula "separate" to enhance stability of the ankle joint.

The concave tibiofibular segment slides forward on the trochlear surface of the talus. Tibia rotates over the talus. The wider anterior portion of the talus wedges into the mortise. The tibia and fibula "separate" to enhange stability of the ankle joint.

What type of motion does talus & calcaneous produce? why?

They create a twisting triplanar motion creating pronation & supination Articulating surfaces btw the two bones changes bcuz of facet orientation

Weight-Bearing Hindfoot Supination and Transverse Tarsal Joint (Pg 17)

Tibia ER, it drags the talus into lateral rotation (produces relative IR of calcaneus)= hindfoot supination With supiantion occuring at subtalar joint through LR of tibia, transverse tarsal joint has limited ability to pronate to maintain fixed position of forefoot, will begin to: A) supinate w/greater range of subtalar supination & lateral rotation of leg B) or will fully supinate along with a fully supinated subtalar joint C) and maximal lateral rotation of superimposed leg Page 461 in book

What is the "more posterior" position of lateral malleolus due to?

Tibial torsion. This is the amount ot ''twist'' in the tibia when you compare the proximal surface to the distal surface. It is kind of like the amount of torsion we see in the femur, but it usually exists in the opposite direction of the femur. Tibial torsion is one of the reasons that people stand in ''toe out,'' and it gradually increases from birth to 10 years of age. The more torsion that exists, the more displacement of the axis of motion in the transverse plane.

Long plantar ligament: located? Runs from?

it is located inferiorly along the lateral surface of the foot - runs from the calcaneus to the cuboid, but then it continues on to the bases of the second, third, and fourth metatarsal, providing support to the transverse tarsal joints and the longitudinal arch of the foot.

How do you identify a Forefoot varus deformity?

manually placing the non-weightbearing calcaneus in subtalar neutral position &determining whether the forefoot is deviated in the frontal plane from a line bisecting the calcaneus

Rule of thumb to quantify pronation/supination at Transverse Tarsal joint?

pronation/supination at the transverse tarsal joint is about 1/3 to 1/2 that of the hindfoot.

Spring Ligament

supports the talar head; one of the most important passive stabilizers of medial longitudinal arc

Pronation Twist: Hindfoot & TTJ are stuck in supination, then tarsometatarsal joint will...

will abduct for this with a pronation, eversion twist. 1.GRF force 4th &5th rays into dorsiflexion 2. toe flexors pull 1st &2nd rays into plantarflexion to maintain contact with ground 3. EVersion accompanies plantarflexion movement of 1st&2nd rays, as well as dorsiflexion of 4th & 5th rays