Ankle and Foot Flashcards
What motion are the tib-fib joints important for?
DF and PF
Which tib fib joint has more motion?
Proximal
How much compressive force passes through the talus and tibia?
90-95%
Subtalar joint
Talus and Calcaneus
- Responsible for inversion/ eversion
- There are three articulations between these two bones (posterior, middle, anterior)
- Posterior articulation is 70% of surface area
Transverse tarsal joint
AKA midtarsal joint, Chopart’s joint
- Connects rearfoot with forefoot
- Very versatile
- Allows for adaptation to altering surfaces
- 2 joints: Talonavicular and Calcaneocuboid
Talonavicular Joint
- Medial component of transverse tarsal joint
- Convex talus, concave navicular
- Spring ligament
- Interosseous ligament
- Several other smaller ligaments
Spring Ligament
Spans from sustentaculum of the calcaneus to the medial-plantar surface of the navicular
- aka plantarcalcaneonavicular ligament
- little elastin - much collagen –> very taught
Maintains medial-longitudinal arch
Calcaneocuboid Joint
Lateral component of transverse tarsal joint
- Joint surfaces form an interlocking wedge that resists sliding
- Less motion than at the talonavicular joint
- Dorsal calcaneocuboid ligament, bifurcated ligament, long and short plantar ligaments
Distal Intertarsal Joints
Collection of 3 joints or joint complexes
- Cuneonavicular
- Cuboideonavicular
- Intercuneiform and cuneocuboid joint complex
Two functions
- Pronation/ supination
- Stability across the transverse arch of the foot
Tarsometatarsal Joints
AKA Lisfranc joint
- No measurable motion available
- Motion consists of gliding between segments
- Strong ligaments and joint congruence factors limit motion
Metatarsophalangeal joints
- Convex MT, cancave proximal phalanx
- PF (65) and DF (30-40) available
- ABD and ADD available in small amounts (use second digit as reference) - more apparent as compensation
First MTP Joint
- Flex: 45
- Ext: 70
Use 55 degrees extension in normal gait
Clinical significance: Hallux rigidus can lead to hallux valgus
Proximal Tibiofibular Osteokinematics
Important in DF Loose-pack position: Knee in mid range, ankle in 10 degrees PF Closed-pack position: Ankle in full DF Fibula glides: - Superiorly with DF - Inferiorly with PF
Distal Tibiofibular Joint
Ligaments:
- Interosseous lig
- Anterior inferior tibiofibular lig
- Posterior inferior tibiofibular lig
Loose-pack position: 10 degrees PF
Closed-pack position: Full DF
High ankle sprain
AKA syndesmosis sprain
- Disruption of tib fib ligaments and interosseous membrane
- Can occur with forced dorsiflexion and/ or eversion
- Rotational MOI
- Slow recovery
- Often associated with fx
- Significant laxity may require ORIF
Kleiger’s Test
High Ankle Sprain test