Functional Joints of the Foot (Part 2) Flashcards
1
Q
Midtarsal joint
A
- Transverse Tarsal Joint
- Chopart’s Joint
- Two separate anatomical joints
- Two common axes of motion
- Joints move together
2
Q
Two anatomical joints of the midtarsal joint
A
- Talonavicular
- Calcaneocuboid
3
Q
Talonavicular joint
A
- Panarthrodial
- The long axis
- Highly adjustable in stance
4
Q
Calcaneocuboid joint
A
- Saddle shaped
- The oblique axis
- “Locks” the lateral column
- Anterior medial overhang of distal calcaneus
- Inferomedial process of the cuboid
5
Q
Bifurcate/Chopart’s ligament
A
- Y-shaped originating from anteromedial corner of sinus tarsi
6
Q
Medial portion of bifurcate ligament
A
- Calcaneonavicular ligament
7
Q
Lateral portion of bifurcate ligament
A
- Calcaneocuboid ligament
8
Q
Ankle sprains with bifurcate ligament
A
- May cause avulsion of anterior superior process of calcaneus with inversion ankle injuries
9
Q
Plantar calcaneonavicular (spring) ligament attachments
A
- Runs from sustentaculum tali to the navicular tuberosity to support the talar head
10
Q
Plantar calcaneonavicular (spring) ligament
A
- Possesses a thick fibrocartilaginous layer dorsally
- Helps to maintain integrity of medial longitudinal arch
11
Q
Plantar calcaneocuboid (short plantar) ligament
A
- Short, wide and very strong!
- Supports the lateral longitudinal arch
12
Q
Plantar calcaneocuboid (short plantar) ligament attachments
A
- Runs from plantar surface of calcaneus to plantar surface of cuboid
13
Q
Long plantar ligament
A
- Helps to provide the floor of the canal the peroneus longus passes through
14
Q
Long plantar ligament attachments
A
- Runs from plantar surface of calcaneus and cuboid, in front of the tuberosity, to the bases of the second, third and fourth metatarsal base
15
Q
Midtarsal joint longitudinal axis
A
- Allows frontal plane movement of the forefoot
- Comprised of the talonavicular joint
- Dictates movement of the medial column of the foot
- Pronatory/supinatory
16
Q
Midtarsal joint oblique axis
A
- Allows sagittal and transverse plane movement of the forefoot
- Comprised of the calcaneocuboid joint
- Dictates movement of the lateral column of the foot
- Pronatory/supinatory
17
Q
Longitudinal axis of MTJ anatomy
A
- Ball and socket joint
- Almost parallel to the long axis of the foot
18
Q
Longitudinal axis of MTJ positioning
A
- 9° from the sagittal plane
- 15° from transverse plane
- Predominantly frontal plane motion
19
Q
Longitudinal axis of MTJ range of motion
A
- Minimum: 4 - 6°
- Average: 8°
- Pronatory/supinatory axis
20
Q
Longitudinal axis of MTJ runs
A
- From MAD
- Lateral, posterior and plantar to:
- Medial, Anterior and Dorsal
21
Q
Oblique midtarsal joint anatomy
A
- Saddle joint
- Among the least mobile joints of the foot
- High degree of angulation from transverse and sagittal planes
22
Q
Oblique midtarsal joint axis positioning
A
- 52° from sagittal plane
- 56° from transverse plane
- Predominantly sagittal and transverse plane motion
23
Q
Axes of MTJ and their ROM
A
- Oblique Axis – 22° average ROM
- Longitudinal Axis – 8° average ROM
24
Q
Neutral position of midtarsal joint
A
- “Locked” midtarsal joint
- Maximally pronated position
- There should be NO sagittal plane motion when the heel comes off the ground
- Enables the foot to function as a second class lever
25
Neutral position of midtarsal joint lever components
- Fulcrum – metatarsal-phalangeal joint axis
- Effort – gastrocsoleus complex
- Load – rearfoot and weight bearing load of body
26
Locking mechanism of the OMTJ
- Osseous mechanism
| - Ligamentous mechanism
27
Osseous portion of OMTJ locking mechanism
- Concave-convex OMTJ
- Rotation of cuboid on calcaneus
- Pronation
28
Pronation of osseous mechanism of OMTJ locking involves
- Dorsal movement
- “Packing” of the joint
- Dorsal lateral aspect of calcaneus limits movement
29
Parallelity of axes
- Subtalar joint cannot move independently of MTJ
- With pronated STJ…MTJ axes become more parallel
- Facilitates unlocking
- Mobile Adaptor role
30
Medial arch support in static stance involves
- Plantar fascia
- Long Plantar ligament
- Short Plantar ligament
- Spring ligament
31
Plantar fascia
- Originates from plantar calcaneal tubercles
- Divides into five slips to insert into bases of distal phalanges and plantar plates
- Receives some fibers from tendo achilles
32
Functions of the plantar fascia
- Supports the medial arch
- Bears 25 to 33% weight bearing load
- Aids in OMTJ pronation during propulsion
- Acts as a shock absorber
- Elevate the arch at heel off
- Windlass action of Hicks (passive action)
33
The first ray consists of
- First cuneiform
- First metatarsal
- Hallux
34
Flat joints of the first ray
- First cuneiform-navicular joint
| - First cuneiform-first metatarsal joint
35
First ray motion
- Non-pronatory-supinatory axis of motion
36
First ray axis runs
- Medial-plantar-posterior to lateral-dorsal-anterior
37
First ray axis positioning
- 9° from transverse plane
- ~45° from sagittal and frontal planes
- Runs lateral, anterior and distal L-A-D
38
Motion of the first ray axis
- Nearly all motion in frontal and sagittal planes
| - Very close to being a biplanar joint
39
First ray function/movements
- Non-pronatory/non-supinatory
- Inverts w/ dorsiflexion
- Everts w/ plantarflexion
40
First ray ROM
- 5 mm dorsiflexion
- 5 mm plantarflexion
- Start point: level of the second metatarsal
41
First metatarsophalangeal joint
- Articular facets of four bones within one synovial capsule
- First metatarsal head
- Proximal phalanx of hallux
- Tibial sesamoid
- Fibular sesamoid
- Condylar joints
42
First MTPJ
- Most complex of MTPJ
- Most important for propulsion
- “Dynamic acetabulum”
- Likened to a hammock
43
First MTPJ is likened to a hammock
- Metatarsal head rocks:
- Plantarly on the sesamoids and soft tissue
- Distally within the base of the proximal phalanx
44
Movement of the first MTPJ is primarily dorsifelxion and plantarflexion
- Minimum of 65 to 75º dorsiflexion required for toe off
- With elevation of first metatarsal, range of motion decreases
- Interphalangeal joint can provide up to 35º of motion
- Etiology for hallux limitus
45
Hubscher maneuver
- Evaluates first ray hypermobility (first ray and MTPJ position)
- With dorsiflexion of first ray, range of motion at MTPJ decreases
- “Jamming” occurs with MTPJ arthritic pain
- Good for evaluating orthotic control of medial column
46
First ray hypermobility
- Inability to stabilize first ray against the ground
| - Peroneus longus has decreased plantarflectory vector
47
Congruent malalignment of first MTPJ
- Joint surfaces are parallel
48
Deviated malalignment of first MTPJ
- Joint surfaces intersect outside the joint
49
Subluxed malalignment of first MTPJ
- Joint surfaces intersect within the joint
| - Stress reactions evident in lesser metatarsals
50
Metatarsal break angle
- Normal parabola: 2 > 1 > 3 > 4 > 5
| - Angle second and fifth metatarsal heads - 62°
51
Metatarsal break angle (2-5)
- Toe off occurs about this axis (62°)
- Contributes to inversion of the rearfoot
- Abnormal parabola may cause uneven weight distribution during propulsion
52
Fifth ray
- Consists of fifth metatarsal only
53
Fifth ray axis (root)
- 20° from transverse plane
- 35° from sagittal plane
- Pronatory/supinatory
54
Fifth ray ROM
- May be evaluated as excursion
| - 1-3 mm up to 10-12 mm
55
Fourth intermetatarsal angle (fifth ray)
- 6.5 – 8°
| - Average 7.1°
56
Lateral deviation angle (fifth ray)
- Average 2.64°
57
MTPJ axes
- Pass perpendicular to the vertical axis of the MTPJ (strong abductors and adductors)
- Pass just below the transverse plane of the joint axis (very weak plantarflexors)
- Insert into the extensor expansion
