MSK Lower Leg, Ankle, & Foot Flashcards
Name the components in the anterior compartment of the leg: 7
Muscles:
- Tibialis anterior (DF/Inversion) (L4/5)
- Extensor HallicusLongus (DF/Inversion) (L4/5/S1)
- Extensor Digitorum (DF/Eversion) (L5/S1)
- Peroneus tertius (DF/Eversion) (L5/S1)
Nerve - Deep peroneal nerve (L4/5/S1)
Anterior tibial artery and vein
Name the components of the lateral compartment of the leg: 3
Muscles:
- Peroneus brevis (everter/weak PF)
- Peroneus longus (Everter/weak PF)
Nerve - superficial peroneal nerve - L5/S1
(here the common peroneal nerve divides into the superficial and deep branches.
Name the components of the deep and superficial posterior compartment of the leg
Deep posterior compartment:
- Flexor digitorum longus (Flexion of lateral 4 toes, Inversion, PF: Tib L5-S2)
- Flexor Hallucis longus (Tib S2-3)
- Tibialis posterior (inversion/PF: Tib L5-S2)
- popliteus muscle (IR of leg on femur: Tib L5-S2)
- Nerve: Tibial nerve
- Posterior tib artery and vein
Superficial posterior compartent:
- Gastrocnemius (PF - tib L5-S2)
- Soleus (PF: Tib - L5-S2)
- Plantaris (weak PF: Tib - L5-S2)
____ is a condition marked by chronically raised intracompartmental pressure.
what is the source of pain in this condition
Chronic exertional compartment syndrome (CECS)
Pain could be due to tissue ischemia due to restricted arterial inflow, obstruction of microcirculation, or arteriolar or venous collapse. Also could be sensory receptor stimulation in fascia or periosteum caused by high pressure; or the release of biochemical factors caused by reduced blood flow.
In CECS (Chronic exertional compartment syndrome) pain will usually occur with ____
exercise and progress as the activity increases in intensity. Pain diminishes after activity is stopped.
Name presentations of the varius CECS (chronic external compartment syndromes):
- Anterior
- Lateral
- Deep posterior
- dorsiflexor weakness, numbness over the first web space of the dorsum of the foot - deep peroneal nerve)
- dorsiflexor weakness and first web space numbness (deep peroneal nerve) or foot evertor weakness and numbness of the dorsal foot and anterolateral distal shin
- cramping of the foot intrinsics and numbness of the medial arch of the foot (tibial nerve)
In chronic exertional compartment syndrome (CECS), discuss a positive test when measuring compartment pressure
manometric techniques are best means. Elevated pressures should coincide with reproduction of the exact pain syndrome.
pressures are measured pre-and post exercise. A delay in return to pre-exercise pressure levels of 6-30 mins is required for a positive test.
In acute compartment syndrome, necrosis of muscle and nerve tissue can develop in as little _______
4-8 hours
Which two areas of the body are most commonly affected by acute compartment syndrome
volar aspect of the forearm
anterior compartment of the leg
describe sequelae of untreated compartment syndrome: 4
- tissue necrosis
- secondary muscle paralysis
- muscle contractures
- sensory impairment - Volkmann’s ischemic necrosis
results in claw hand or foot caused by contractures
What is the sensory impairment called in acute compartment syndrome
Volkmanns ischemic necrosis.
First symptoms in acute compartment syndrome:
What are the 3 Ps of this?
Intractable pain, and sometimes sensory hypesthesia distal tothe involved compartment (usually top of the foot and median distribution of the hand)
Pain, Paresthesia, paralysis
In acute compartment syndrome, after cast removal, what is the most important physical sign?
extreme pain with stretching of the long muscles passing through a compartment.
NOTE: pulses are usually completely normal in ACS because of intracompartmental pressure rarely exceeding systolic or MAP.
General guidelines for acute compartment syndrome (ACS) and manometry is:
the presence of compartment syndrome when the diastolic pressure minus the intracompartmental pressure is < or = 20mmHg
____, also known as shin splints, is a common cause of exercise-induced leg pain. Etiology?
Medial tibial stress syndrome (MTSS)
results from chronic traction on the periosteum at the periosteal-fascial junction. The periosteum may be come detached from the bone due to ballistic overload. Fibrofatty filling may occur at the site of the defect.
What is the major predisposing factor for medial tibial stress syndrome (MTSS)?
hyperpronation
_____ occur when repetitive loading causes irreversible bone deformation. These develop with continued overuse they can coalesce and propagate through the bone to become symptomatic
Stress fractures.
Low bone mineral density impose a higher risk for stress fractures. causes of low BMD? 4
- females with late onset menses
- individuals with low body weight (<75% ideal body weight)
- Poor nutrition correlates with lower calcium intake
- tobacco and alcohol use
Biomechanical conditions can lead to higher risk of stress fractures: 2
- over pronation places higher stress on fibula and tibia (genu valgum and a wide gait pattern may cause over-pronation)
- Leg length discrepancies
- muscle imbalances
- lack of flexibility
- malalignment factors can also place high forces on the lower leg.
External factors: classic training errors of increasing intensity and length of activity abruptly or causing excessive fatigue; also running on hard surfaces or using worn-out shoes
Top three sites of LE stress fractures in runners
34% Tibia
24% Fibular
20% Metatarsals (2nd > 3rd > other)
deliniate the progression of stress fractures appearance on XR as time progresses
- May not be seen for 2-3 weeks after symptoms develop
- Periosteal thickening appears first
- cortical lucency
- Linear stress fracture appears as a lucency within a thickened area of cortical hyperostosis during healing.
** bone scans are used when radiographs are negative and stress fracture is highly suspected. (100% sensitive but low in specificity)
When will a bone scan turn positive in stress fractures?
third phase
- tumors, osteomyelitis, bony infarct, bony dysplasias can also cause localized increased uptake.
MRI is becoming the first-choice means of investigating stress fractures.
Treatment of stress fractures.
- If pain on normal ambulation:
- ____ can begin immediately.
- ____ activities can be used to maintain cardiac fitness.
- Atleast _____ of pain free normal ambulation should be achieved before returning to impact activity.
- Supplement?
- NWB for 7-10 days
- NSAIDs, ICE, muscle strengthening and stretching.
- Non impact activities such as cycling and swimming
- 1-2 weeks
- 1500mg QD calcium with 400-800 IU of Vit D
Impact activity is started cautiously at low intensity for short periods (10-15 mins) in the first few days and increased incrementally as tolerated.
Orthotics are useful adjunct to tx and may decrease impact force and help correct excessive supination or pronation.
Softer running surfaces should be considered.
Describe the components of the ankle mortise
- Distal tibia - makes up medial malleolus and the superior articular surface of the ankle mortise joint.
- Distal fibula - forms the lateral malleolus and the superior articular surface of the ankle mortise joint
- lateral mall extends more distally than the medial mall, making it very important in ankle stabilization. - Talus (4 parts)
- body
- neck
- head
- dome
It has a fragile blood suppl, which can lead to complications of healing.
Name the bones of the foot: How many?
28
7 Tarsals - Talus, calcaneus, navicular, cuboid, 3 cuneiforms (medial, intermediate, and lateral)
5 metatarsals
14 phalanges (proximal, middle, distal - the great toe only has proximal and distal phalanges)
2 sesamoid bones (located on the plantar surface of the head of the first metatarsal)
Which ligaments make up the lateral aspect of the ankle 3
- Anterior talofibular ligament - primary lateral ankle ligament stabilizer; most commonly injured ligament
- Calcaneofibular ligament (CFL)
- Posterior talofibular ligament (PTFL)
Which ligaments make up the medial aspect of the ankle?
Main ligament?
Deep and superficial
The deltoid ligament stabilizes the medial ankle joint and is stronger than the lateral ligaments.
Deep: (more important for stabilization)
- Anterior tibiotalar
- Posterior tibiotalar
Superficial
- Tibionavicular
- tibiocalcaneal
- Spring ligament (posterior calcaneonavicular ligament)
- Medial and posterior talocalcaneal ligaments
Importance of deltoid ligament
Deltoid ligament maintains close proximity of the medial mall and talus preserving the medial longitudinal arch of the foot.
Name the ligaments of the anterior aspect of the ankle joint 4
Comprised of 4 ligaments that maintain the integrity of the distal tibia and fibula as well as resisting any forces that would separate the 2 bones.
- Anterior tibiofibular ligament
- Posterior tibiofibular ligament
- Transverse tibiofibular ligament
- Interosseous ligament.
Name the 2 ligaments of the foot
- Lisfranc Ligament - connects the second MT head to the first cuneiform
2 Transverse metatarsal ligament
Normal ROM of the ankle:
DF:
PF:
Dorsiflexion: 20 degrees
Plantarflexion: 50 degrees
Normal ROM of the foot:
Subtalar joint:
Inversion:
Eversion:
Forefoot:
Abduction:
Adduction:
First MTP
Flexion:
Extension:
Subtalar joint
Inversion: 5
Eversion: 5
Forefoot:
abd: 10
add: 20
First MTP
Flexion: 45
Extension: 80
Muscles responsible for DF 4
Divide into inverters and everters:
Inversion
- tib ant (deep peroneal L4/L5)
- extensor hallucis longus (deep peroneal (L4)/L5/S1)
Eversion:
- Extensor digitorum longus (deep peroneal L5/S1)
- Peroneus tertius (deep peroneal L5/S1)
Name the Posterior muscles that cause plantar flexion and inversion. 6
- Tibialis posterior (Tib nerve - L4/5)
- Flexor digitorum longus (Tibial nerve - S1/S2)
- Flexor hallucis longus (Tibial nerve S2/3)
- Plantaris (Tibial nerve S1/2)
- Gastrocnemius (Tibial nerve S1/2)
- Soleus (Tibial nerve S1/2)
Name the Lateral muscles involved in plantar flexion and eversion.
1 Peroneus longus (superficial peroneal nerve L5-S2)
2. Peroneus brevis (superficial peroneal nerve L5-S2)
Name all plantar flexors of the foot. 8
- Tibialis posterior (Tib nerve - L4/5)
- Flexor digitorum longus (Tibial nerve - S1/S2)
- Flexor hallucis longus (Tibial nerve S2/3)
- Plantaris (Tibial nerve S1/2)
- Gastrocnemius (Tibial nerve S1/2)
- Soleus (Tibial nerve S1/2)
1 Peroneus longus (superficial peroneal nerve L5-S2) - Peroneus brevis (superficial peroneal nerve L5-S2)
Basically all of lateral and posterior compartments of the leg minus popliteus
Name the toe flexors (8)
- Flexor dig longus (Tib S2/3)
- Flexor hallucis longus (Tib S2/3)
- Flexor dig brevis (medial plantar nerve (tib S2/3))
- Flexor Hallucis brevis (medial plantar nerve (tib S2/3))
- Quadratus plantae (lateral plantar nerve (tib S2/3))
- Interossei (lateral plantar nerve (tib S2/3))
- Flexor digiti minimi brevis (lateral plantar nerve (tib S2/3))
- Lumbricals
- 1st lumbrical (medial plantar nerve (tib L4/5)
- Second, third, and forth lumbricals (lateral plantar nerve (tib S2/3)
Name the 4 toe extensors
- Extensor digitorum longus (deep peroneal nerve L5/S1)
- Extensor hallucis longus (deep peroneal nerve L5/S1)
- Extensor digitorum brevis (deep peroneal nerve: S1/S2)
- Lumbricals
- 1st lumbrical (medial plantar nerve (tib L4/5)
- Second, third, and forth lumbricals (lateral plantar nerve (tib S2/3)
Name the 3 toe abductors
- abductor hallucis (medial plantar nerve (tibial S2/3)
- Abductor digiti minimi (lateral plantar nerve (tib S2/3)
- Dorsal Interossei (lateral plantar nerve Tib S2/3)
Name the 2 toe adductors
- Adductor hallucis (lateral plantar nerve tib S2/3)
2. Plantar Interossei (lateral plantar nerve Tib S2/3)
What is the most common ankle sprain?
Mechanism of injury?
lateral ankle sprains _ account for up to 85% of all ankle sprains
inversion on a plantar flexed foot
Name the injured ligaments in lateral ankle sprain (in order)
- Anterior talofibular ligament (ATFL)
- Calcaneofibular ligament (CFL) - stabilizes ankle during inversion
- Posterior talofibular ligament (PTFL)