1000075755.jpg
Refer every line make it easier for read and write without changing meaning
Here is the content from Chapter 13 - Arches of Foot, rewritten for easy reading and note-making:
Chapter 13: Arches of Foot
Definition
- The skeletal structure of the foot is arranged in an arched shape - both lengthwise (longitudinal) and sideways (transverse).
- The hollow/concave side of these arches faces the sole (plantar surface).
- These arched bony arrangements are called arches of the foot.
Note: Arches are present from birth, but in infants they appear flat because of excess fat in the soles.
Why Are Arches Important?
The foot is unique to humans. Arches help in:
- Fast walking, running, and jumping
- Weight-bearing
- Maintaining upright posture
- Footprints are incomplete because of the arches
Functions of the Foot
The foot has two main roles:
- Pliable platform - supports body weight in upright posture
- Lever - propels the body forward during walking, running, or jumping
To fulfill these roles, the foot is designed as elastic arches (springs). These arches:
- Are segmented
- Can sustain stress of weight and thrust
- Make the sole concave
- Best seen in footprints showing weight-bearing parts of the sole (Fig. 13.1)
Classification of Arches
1. Longitudinal (Flowchart 13.1)
- Medial
- Lateral
2. Transverse
- Anterior
- Posterior
Longitudinal Arches
Medial Longitudinal Arch
- Considerably higher, more mobile, and more resilient than the lateral arch
- Considered a big arc of a small circle
- Has more bones and more joints (Figs. 13.2 and 13.3)
Bones forming the Medial Longitudinal Arch:
- Calcaneum (medial part)
- Talus
- Navicular
- Cuneiforms
- Medial three metatarsals
Bones forming the Lateral Longitudinal Arch:
- Calcaneum (lateral part)
- Cuboid
- Lateral two metatarsals
Competency AN19.5: Describe factors maintaining important arches of the foot with its importance.
1000075756.jpg
Refer every line make it easier for read and write without changing meaning
analyse_media
Here is the full content rewritten for easy reading and note-making:
Flowchart 13.1: Arches of Foot
Arches of Foot = Arched bony arrangement of the foot
Comparison Table: Longitudinal vs Transverse Arches
| Feature | Medial Longitudinal Arch | Lateral Longitudinal Arch | Anterior Transverse Arch | Posterior Transverse Arch |
|---|---|---|---|---|
| Quality | More mobile, resilient | Less mobile, rigid | - | - |
| Shape | Big arc of small circle | Small arc of big circle | - | - |
| Anterior end | Heads of first 3 metatarsals | Heads of 4th and 5th metatarsals | - | - |
| Posterior end | Medial tubercle of calcaneum | Lateral tubercle of calcaneum | - | - |
| Summit | Superior surface of talus | Superior surface of calcaneum | - | - |
| Key joint | Talocalcaneonavicular joint | Calcaneocuboid joint | - | - |
| Key stone | Head of talus | Cuboid | - | - |
| Bones | Talus, navicular, 3 cuneiforms, first 3 metatarsals, medial 1/2 of calcaneum | Cuboid, 4th and 5th metatarsals, lateral 1/2 of calcaneum | Head of metatarsals | Tarsals, base of metatarsals |
| Completeness | - | - | Complete | Incomplete (forms half of dome) |
| Bony factors | - | - | Round-shaped head of metatarsals | Wedge-shaped cuneiforms and bases of metatarsals |
| Tie beams | - | - | Adductor hallucis, deep transverse metatarsal ligaments | Flexor hallucis brevis, intertarsal ligaments |
| Slings | - | - | Peroneus longus and tibialis posterior | Peroneus longus and tibialis posterior |
Medial Longitudinal Arch
Bones
- Calcaneus, talus, navicular, all three cuneiform bones, and 1st-3rd metatarsals
Ends
- Anterior end - formed by heads of the 1st, 2nd, and 3rd metatarsals
- Note: Phalanges do NOT take part in forming the arches
- Posterior end - formed by the medial tubercle of the calcaneum
- Keystone - the talus
Summit
- Formed by the superior articular surface of the body of the talus
Pillars
- Anterior pillar - long and weak
- Formed by: talus + navicular + 3 cuneiforms + first 3 metatarsal bones
- Posterior pillar - short and strong
- Formed by: medial part of the calcaneum
Main Joint
- Talocalcaneonavicular joint
Lateral Longitudinal Arch
- Characteristically low, with less bones and less joints
- Has limited mobility
- Built to transmit weight and thrust to the ground
- Considered a small arc of a big circle (Figs. 13.2 and 13.3)
- Acts as a shock absorber (unlike medial arch which acts as spring)
Bones
- Calcaneus, cuboid, 4th and 5th metatarsals
Ends
- Anterior end - formed by heads of the 4th and 5th metatarsal bones
- Posterior end - formed by the lateral tubercle of the calcaneum
- Keystone - the cuboid
Summit
- Lies at the level of the articular facets on the superior surface of the calcaneum at the level of the subtalar joint
Pillars
- Anterior pillar - long and weak
- Formed by: cuboid + 4th and 5th metatarsals
- Posterior pillar - short and strong
- Formed by: lateral half of the calcaneum
Main Joint
- Calcaneocuboid joint
Factors Responsible for Maintenance of Longitudinal Arches
For maintenance of longitudinal arch - the proper maintenance of shape of arch with its elastic properties is needed.
1. Ligaments (most important factor)
- Interosseous talocalcaneal ligament - connects talus and calcaneum
2. Muscles, Tendons and Aponeurosis
a. Sling action:
- The sling pulls the summit of the arches upward
- Muscles involved:
- Tibialis posterior
- Flexor hallucis longus
- Flexor digitorum longus
- (These are muscles of the posterior compartment of the leg)
b. Tie beams:
- Tie beams prevent separation of the pillars
- Tie beams of the medial longitudinal arch include... (continued on next page)
Tip for notes: The medial arch = spring (mobile, resilient) | The lateral arch = shock absorber (rigid, low, stable)
1000075758.jpg
Refer every line make it easier for read and write without changing meaning
Here is the full content rewritten for easy reading and note-making:
Factors Responsible for Maintenance of Longitudinal Arches
For maintenance of the longitudinal arch, the shape of the arch with its elastic behaviour must not get altered during weight transmission.
The factors maintaining the longitudinal arches are (Figs. 13.4 to 13.6 and Table 21.2):
- Shape of the bones concerned
- Intersegmental ties/staples - ligaments (and muscles) that hold the different segments of the arch together
- Tie beams or bowstrings - connect the two ends of the arch
- Slings - keep the summit of the arch pulled up
The factors maintaining the arches of the foot can be understood by the example of a stone bridge.
A. Factors Maintaining Medial Longitudinal Arch
(Figs. 13.4 and 13.5)
1. Bones
- The sustentaculum tali partly supports the heads of the talus
2. Ligaments
The following ligaments act as intersegmental ties to maintain the medial longitudinal arch:
- Spring ligament - supports the head of talus
- Interosseous ligaments - connect adjacent bones
- Interosseous talocalcaneal ligament - connects talus and calcaneum
3. Muscles, Tendons and Aponeurosis
a. Sling action:
- Sling pulls the summit of the arches upward
- Muscles involved:
- Tibialis posterior
- Flexor hallucis longus
- Flexor digitorum longus
- (All are muscles of the posterior compartment of the leg)
b. Tie beams:
- Tie beams prevent separation of the pillars
- Tie beams of the medial longitudinal arch include:
- Plantar aponeurosis
- Abductor hallucis
- Flexor hallucis brevis
B. Factors Maintaining Lateral Longitudinal Arch
(Figs. 13.4 and 13.5)
1. Bones
- Shape of the cuboid (keystone of lateral longitudinal arch) helps to maintain the lateral longitudinal arch
2. Ligaments
- The lateral longitudinal arch is supported by:
- Short plantar ligament
- Long plantar ligament
3. Muscles, Tendons and Aponeurosis
a. Sling action:
- Slings pull the summit of the arch upward
- Slings of the lateral longitudinal arch include:
- Tendon of peroneus brevis
- Peroneus tertius
- Peroneus longus
b. Tie beams:
- Tie beams prevent separation of the pillars
- Tie beams of the lateral longitudinal arch include:
- Plantar aponeurosis
- Intrinsic muscles of the little toe:
- Lateral part of flexor digitorum brevis
- Abductor digiti minimi
- Flexor digiti minimi
Lateral Longitudinal Arch - Pillars (continued from previous page)
2. Posterior pillar - short and strong
- Formed by the lateral half of the calcaneum
Main Joint:
- Calcaneocuboid joint
Fig. 13.4 - Factors maintaining the medial longitudinal arch (Shows: Tibialis anterior, Tibialis posterior, Flexor hallucis longus, Spring ligament, Plantar aponeurosis - Medial view)
Fig. 13.5 - Factors maintaining lateral longitudinal arches (Shows lateral view with: Peroneus longus, Peroneus brevis, Tibialis anterior / Short plantar ligament, Long plantar ligament, Plantar aponeurosis)
This is a shared conversation. Sign in to Orris to start your own chat.