Foot and Ankle Problems (Session 5) Flashcards
What is the usual mechanism for an ankle fracture?
Inversion/eversion injury
What co-morbidities may affect fracture healing?
Diabetes, neuropathy, peripheral vascular disease, smoking
If a patient has fracture blisters why does surgery need to be delayed?
Allow the blisters to heal
Why do open ankle fractures require urgent surgery?
Reduce risk of osteomyelitis (requires extensive irrigation and debridement)
Osteomyelitis= bone infection
Define an ‘ankle sprain’
Partial/complete tear of 1+ ligaments of ankle joint
What’s the porgnosis for an ankle sprain?
- 90% heal with rest
- Some cause late ankle instability, sometimes require surgery
Give some factors for increased risk of ankle sprains
- Weak muscles/tendons that cross ankle joint
- Weak/lax ankle ligaments
- Inadequate joint poprioception
- Slow neuromuscular response to an off-balance position
- Running on uneven surfaces
- Shoes with inadequate heal support
- Wearing high-heeled shoes
What causes ankle sprains?
Excessive strain on ligaments of ankle: excessive external rotation, inversion, eversion
What is the most common mechanism of injury in ankle sprains?
Inversion injury
Affecting plantar-flexed and weightbearing foot
Anterior talofibular ligament most at risk of sprain
What is an avulsion fracture?
Tendon/ligament=placed under tension
Instead of tendon/ligament tearing, fragment of bone= pulled off at insertion site
In children, what could an unfused 5th metatarsal apophysis be confused with on an x-ray?
5th Metatarsal fracture
In what age group does an achilles tendon rupture most commonly occur?
30-50years
State 3 mechanisms of injury for an achilles tendon rupture?
- Forceful push-off with extended knee (jumping)
- Fall with foot outstretched in front and ankle dorsiflexed
- Falling from height/abruptly stepping into hole/off kerb
What is the ‘vascular watershed’ area on the achilles tendon?
- 6cm proximal to insertion of achilles tendon onto calcaneal tuberosity
- Area of decreased vascualrity and thickness
Area MOST SUSCEPTIBLE to tearing
What are the signs/symptoms of an achilles rupture?
- Sudden, severe pain at back of ankle/in calf
- Sound of loud pop/snap
- Palpable gap/depression
- Initial pain and swelling followed by bruising
- Inability to stand on tip toe or to push-off whilst walking
What test can be used to test for a ruptured tendon?
Thompson test
What other tests are used to demonstrate the gap in the Achilles tendon?
MRI
Ultrasound
Why is surgical reconstruction difficult with a ruptured Achilles tendon?
Two ends of the tendon= frayed
How are achilles tendon ruptures treated?
- Conservatively - foot held in aircast boot
- Surgery
What is the re-rupture rate following surgery or conservative management?
2-8%
Why does surgery have a relatively high complication rate?
(5-10% of patients have wound complications)
Overlying skin=poorly vascularised
What is hallux valgus? (3)
- Varus deviation of first metatarsal
- Valgus deviation/lateral rotation of hallux
- Prominence of first metatarsal head
- With/without overlying callus
In which population is hallux valgus most common?
Middle aged females
What is the most common cause of a ‘bunnion’?
:Bony deformity at first metacarpophalangeal joint
Hallux valgus
Give some factors which are thought to cause hallux valgus:
Secondary to:
- Trauma
- Arthritic/metabolic conditions eg gout
- Rheumatoid arthritis
- Psoriatic arthritis
- Connective tissue discorders eg Ehlers-Danlos syndrome
Once hallux valgus is present, the pull of which tendon exarcerbates the problem?
Extensor hallucis longus tendon
Why should surgery on a hallux valgus foot not be carried out for cosmetic reasons alone?
May convert painless foot to painful foot
What surgery can be performed on a hallux valgus?
Metatarsal osteotomy
Realigning fragments
Osteotomy: surgical cutting of a bone, especially to allow realignment
What is Hallux rigidis?
Osteoarthiritis of 1st metatarsophalangeal joint
Why is the 1st metatarsophalangeal joint prone to osteoarthritis?
Joint under tremendous stress during walking
What are the signs and symptoms of hallux rigidus?
- Pain in MTPJ on :
- walking
- attempted dorsiflexion of toe
- Patients tend to compensate- walk on outside of their foot
- Range of dorsiflexion= restricted
- Dorsal bunion (osteophyte) may develop
Useful info: What do the following terms mean?
How is Hallux rigidus managed?
Treatment ladder for OA:
- Activity modification
- Analgesia
- Orthotics/aids
- Intra-articular steroid injections
- Surgery
What surgery may be performed on hallux rigidus?
- Arthrodesis (fusion at 1st MTPJ)
- Arthroplasty (replacement)
What is the major difference between osteoarthritis of the ankle and osteoarthritis of the knee?
Nearly all cases of OA of the ankle are secondary arthritis
What’s the main cause of osteoarthritis in the ankle joint?
Trauma (70-80% post traumatic)
Post traumatic osteoarthritis
What other causes/risk factors are there for osteoarthritis in the ankle?
- Inflammation in the ankle joint (rheumatoid arthritis, reactive arthritis)
- Joint stress (ballet dancers, footballers)
- Obesity
What % of cases of ankle osteoarthritis are primary?
7%
(Older patients, experience less pain, better range of motion compared to secondary osteoarthritis)
How is ankle OA treated?
- Arthrodesis (fusion)
- Results= good
- Often no discernible limp
- Arthroplasty
Name 4 types of toe deformities.
- Claw toe
- Mallet toe
- Hammer toe
- Curly toe
Describe the ‘claw toe’
Usually affect all 4 toes
- MTPJ: hyperextended
- PIP: flexed
- DIP: flexed
Corns may develop over dorsum of toe/under head of metatarsal
What causes claw toes?
- Muscle imbalance-
ligaments and tendons= unnaturally tight
usually due to Neurological damage
- cerebral palsy
- stroke
- diabetes
- alcohol dependence
- Trauma
- Inflammation
- Rheumatoid arthiritis
How do a hammer toe and a mallet toe differ?
Hammer toe: PIPJ: flexed
Mallet toe: DIPJ: flexed
In which toe are hammer and mallet deformities most common?
2nd toe
What are the causes of hammer and mallet toes?
- Ill-fitting pointed shoes- toe in flexed position too long- muscles contract and shorten
- Pressure on second toe from adjacent halux valgus
What causes curly toes?
Congenital
Flexor digitorum longus and flexor digitorum brevis (intrinsic muscles of foot) = too tight
Which digits are usually involved with ‘curly toes’?
3rd-5th digits
Usually bilateral
How are ‘curly toes managed’?
Usually asymptomatic
Conservative treatment- asymptomatic
Surgery rarely needed
What is achilles tendinopathy?
Degenerative, not inflammatory condition
What are the two points where achilles tendinopathy arises?
- Point of insertion of achilles tendon into calcaneum (insertional tendinopathy)
- Vascular watershed area
What are the causes/ risk factors for achilles tendinopathy?
- Overuse (many years) eg long distance runners
- Can occur in inactive people
- Obesity
- Diabetes
What are the signs and symptoms of Achilles tendinopathy?
- Pain/stiffness along achilles tendon in morning
- Pain in tendon worsens with activity
- Severe pain 24hrs after exercising
- Thickening of tendon
- Swelling present all the time- worsened with activity
- Palpable bone spur (w./ insertional tendinopathy)
What is another name for ‘flat foot’?
Pes planovalgus
What is a flat foot?
Collapsed medial arch of foot- medial border of foot almost touches ground
+Valgus angulation of hindfoot
Why is it most young children ‘appear’ flat footed?
Arches not yet developed
Large amount of subcutaneous adipose tissue on sole of foot
- Arch begins to form around 5yrs*
- Abnormal if persists into adolescence*
What is the difference between flexible and rigid flat feet?
-
Flexible:
- No medial arch whilst standing normally
- On tip toes-
- normal medial arch appears
- Valgus deviation into normal alignment
-
Rigid: symptomatic- often requires treatment
- ALWAYS abnormal
- Result of:
- Tarsal coalition: failure of tarsal bones to separate during embryonic development
How can an adult acquire flat feet?
Dysfunction of tibialis posterior tendon
(usually supports medial longitudinal arch of foot whilst walking)
Spring ligament stretches
Plantar aponeurosis stretches
Talar head displaced inferomedially
Medial longitudinal arch= flattened
In which population does an adult acquired flatfoot usually occur?
Middle-aged females
How will someone with adult acquired flatfoot present?
- History of:
- change of shape of foot
- Pain behind medial malleolus
What are the risk factors for an adult acquired flatfoot?
- Obesity
- Hypertension
- Diabetes
- Pregnancy (temporary)- increases laxity of ligaments
How are adult acquire flatfeet managed?
Orthotics (improves symptoms in 80% patients)
Physiotherapy- improve muscle strength
Some- require:
surgical reconstruction
Arthrodesis if secondary OA develops
What % of people with diabetes mellitus are affected by foot disease?
15%
Why does having diabetes mellitus cause foot disease in so many patients? (3)
- Loss of sensation- peripheral neuropathy
- Ischaemia- peripheral arterial disease
- Immunosupression- poor glycaemic control
What foot complications do patients with diabetes mellitus acquire?
Infection
Ulcers
Amputations
How is the risk of acquiring foot disease in patients reduced?
Regular diabetic foot clinics, checked for:
- Corns
- Cracks
- Dry skin
- Sensation and perfusion of feet
- Shoes checked
Patients=educated on how to look after feet
Tight glycaemic control
What causes Charcot arthropathy?
Poorly-controlled diabetes
- Neuropathy
- Abnormal loading of foot
- Repeated microtrauma
- Metabolic abnormalities- osteolysis
- Fractures
- Dislocation
What is Charcot arthropathy?
Progressive destruction of bones, joints, soft tissues
Most common in ankle, foot, knee
What are the signs and symptoms of Charcot arthopathy?
- Reduced ability to detect pain, touch etc
- Continue to walk on foot- make it worse
- Muscle spasticity
- Rocker bottom foot may develop
How is charcot arthopathy treated?
- Optimise glycaemic control
- Reduce load on affected joints (difficult as pain usually not felt and often patient= obese)
