Week 4 - I - Foot and Ankle (1) - Ankle O.A, Hallux valgus & rigidis, Morton's neuroma, Metatarsal stress fracture

Question 1

Ankle OA may be idiopathic / primary OA or as a consequence of previous injury Which sport has players that are particularly prone to ankle OA?

Answer 1

Football players are particularly prone to ankle OA

Question 2

Which movement of the foot may result in anterior damage to the foot with osteophyte formation? When can this osteophyte formation cause pain?

Answer 2

Repeated dorsiflexion may result in anterior damage with osteophyte formation at the 1st metatarsal head

Anterior osteophytes can cause pain during dorsiflexion resulting in impingement

Question 3

What may be carried out as treatment for the anterior osteophytes that arise at the 1st metatarsal head?

Answer 3

Pain on dorsiflexion may be improved with removal of the anterior osteophytes (known as cheilectomy).

Question 4

For patients with significant pain from advanced ankle osteoarthritis, what two surgical options exist as treatment? Which provides more pain relief?

Answer 4

The two surgical options for ankle OA are Arthrodesis - fusion of the ankle joint and Ankle replacement

Ankle arthrodesis and ankle replacements provide equivalent pain relief.

Question 5

Which surgical options for ankle OA * provides better functional outcome? * has higher rates of early loosening? * should be reserved for the elderly?

Answer 5

Ankle replacements may afford better functional outcome due to some preservation of motion however due to the compressive and shearing forces of the relatively small bones, they have higher rates of early loosening

Ankle replacements should also be reserved for elderly patients as once failure occurs, fusion is usually required

Question 6

Which ankle surgery option for OA is thought to perhaps be more reliable as the need for further surgery is much less and re‐operation rates are lower?

Answer 6

Ankle arthrodesis is perhaps a more reliable option than ankle replacement as the need for further surgery is much less and re‐operation rates are lower.

Question 7

What is hallux valgus? Which sex is it more common in?

Answer 7

Hallux valgus is a deformity of the big toe due to medial deviation of the 1st metatarsal head and lateral deviation of the toe itself

The condition is more common in females

Question 8

Hallux valgus is commoner in rheumatoid arthritis and other inflammatory arthropathies as well as some neuromuscular diseases (multiple sclerosis, cerebral palsy). What has been implicated in the development of hallux valgus? What may happen due to the 1st and 2nd toes rubbing together?

Answer 8

The wearing of tight footwear has been implicated in hallus valgus however no evidence exists that shoes tight shoes or high heels are to blame

The first and second toes may rub causing ulceration and skin breakdown

Question 9

What is the common term for hallux valgus? What is the conservative treatment of the condition?

Answer 9

Common term is bunions - usually bilateral

Consevative treatment involves

* wearing wider and deeper ‘accomodating’ shoes to prevent painful bunions

* also use of a spacer (wedge in the first web space) to prevent the toes rubbing together

Question 10

Many patients want surgery to improve the appearance of their foot Why should you be catuois in giving surgery to patients who want it for cosmetic reasons alone?

Answer 10

Should be cautious to giving surgery for cosmetic reasons alone in hallux valgus as these patients often tend to be unhappy with results

Question 11

If conservative treatment for hallux valgus does not work, what is a surgical treatment option?

Answer 11

Excision/resection arthroplasty - also known as Keller’s procedure

Involves osteotomies to realign the bones and soft tissue procedures to tigten slack tissues

Question 12

What is hallux rigidus? Why can it occur?

Answer 12

Hallux rigidus is osteoarthritis of the 1st metatarsophalngeal joint

It can occur as a primary (degenrative) condition or secondary to osteochondral injury

Question 13

Which range of motion can be affected by hallux rigidus? What is the conservative management of the condition?

Answer 13

Hallux rigidus can result in anterior osteophytes at the first MTPJ which can impinge during dorsiflexion of the big toe limiting this motion

Conservative management may involve -

* wearing a stiff soled shoe to limit motion at the MTPJ (insert a metal bar into the sole of a shoe)

* Chieletomy (removal of osteophytes) can also help

Question 14

What is the gold standard surgical treatment for hallux rigidus? What does this prevent woman wearing?

Answer 14

The “gold standard” surgical treatment is arthrodesis.

Successful fusion should alleviate pain with the small sacrifice of no motion (the toe is usually pretty stiff anyway).

Arthrodesis prevents women wearing high heels.

Question 15

What is Morton’s neuroma?

Answer 15

Morton’s neuroma is a painful condition that affects one of the plantar nerves between the toes (plantar interdigital nerves)

Question 16

What do the plantar interdigital nerves arise from? How can they form a neuroma (benign growth of nerve tissue)?

Answer 16

The plantar interdigital nerve arise from the medial and lateral plantar nerves (terminal branches of the tibial nerve)

Repeated trauma to the nerves (ie tight fitting shoes) can cause the nerves to become irritated and swollen resulting in a neuroma

Question 17

Which sex is more commonly affected and what is an implicated cause?

Answer 17

Women are four times more commonly affected than men and the wearing of high heels has been implicated as a cause

Question 18

How does morton’s neuroma present? Which interspace is the most commonly affected?

Answer 18

Morton’s neuroma presents as a burning pain and tingling (paraesthesia) radiating into the affected toes

The third intersapce nerve is the most commonly affected (between third and fourth toe) followed by the second intersapce nerve

Question 19

What may clinical examination of a patient with a ptoential Morton’s neuroma reveal? What test can be carried out on examination - explain it

Answer 19

Clinical examination may reveal loss of sensation in the affected web space

Medio-lateral compression of the metatarsal heads (exerted by squeezing the forefoot with your hand) may reproduce symptoms - pain and paraesthesia or

produce a characterisitc click - this is Mulder’s click test

Question 20

How is Mortons neuroma diagnosed? What is conservative management? What is carried out if it fails?

Answer 20

Ultrasound may be used for diagnosis demonstrating a swollen nerve

Conservative management involves the use of a metarsal pad or offloading insole - steroid and local anaesthetic injections may relive symptoms and aid diagnosis

Neuroma can be excised if necessary

Question 21

The metatarsal bones are the long bones in your foot that connect your ankle to your toes. A stress fracture is a break in the bone that happens with repeated injury or stress. Stress fractures are caused by overly stressing the foot when using it in the same way repeatedly * Which metatarsals head do stress fractures most commonly occur in? * Who do metatarsal stress fractures commonly occur in? (hence their common name?)

Answer 21

Metatarsal stress fractures most commonly occur in the 2nd metatarsal followed by the 3rd metatarsal head

Metatarsal stress fractures are commonly known as march fractures - due to the fact they may occur in

• * runners,
• * in soldiers on prolonged marches,
• * in dancers or
• * during distance walking in people not conditioned or used to prolonged walks

Question 22

Why may xrays not demonstrate a fracture initially in metatarsal fractures? What may be useful for confirming the diagnosis?

Answer 22

Xrays may not demonstrate a fracture for around 3 weeks until resorption at the fracture end occurs or callus begins to appear (soft callus takes around 2-3 weeks to form)

Radionucleotide bone scan may be useful to confirm diagnosis

Question 23

What is the treatment of a metatarsal stress fracture?

Answer 23

Prolonged rest for 6-12 weeks in a rigid soled boot is required to allow healing and resolution of symptoms