Cortex - elective surgery 2 (these are kinda covering a lot of stuff already done so not putting down all the info as its in the previous ones just reiterating some points)

Question 1

What is meant by joint instability and give a few common examples

Answer 1

Instability is abnormal motion of a joint (rotation or translation) resulting in subluxation or dislocation with pain and/or giving way

e.g. knee ligament injuries, recurrent subluxation or dislocation of the shoulder etc

Question 2

What can result in joint instability ?

Answer 2

• Consequence of injury
• Related to ligamentous laxity
• Anatomical variation e.g. genu valgum
• Due to underlying disease process e.g. RA causing subluxation of cervical spine

Question 3

How is most cases of joint instability managed ?

Answer 3

• With physio to strengthen up surrounding muscles and to improve proprioception
• Also may use braces, splints etc to provide additional support

Question 4

What are the different surgical options for joint instability if required

Answer 4

1. Ligament tightening/advancement e.g. ankle instability
2. Ligament reconstruction using tendon graft e.g. ACL reconstruction
3. Soft tissue reattachment e.g. shoulder instability
4. In cases of significant ligamentous laxity e.g. Ehlers danlos - soft tissue procedures unlikely to work so may require fusion
5. If there is a skeletal predisposition to instability e.g. patellar instability may require osteotomy

Question 5

What are the two most common sites that peripheral nerves can become trapped at and how are they treated ?

Answer 5

• Median nerve at the wrist (carpal tunnel syndrome)
• Ulnar nerve at the elbow (cubital tunnel syndrome)

Symptoms can be improved with nerve decompression surgery

Question 6

Spinal nerves can become compressed by disc material or osteophytes causing a radiculopathy - what surgical procedures can be done ?

Answer 6

Spinal decompression or discectomy.

Question 7

Define what is meant by osteomyelitis

Answer 7

Infection of bone

Question 8

What are the ways in which organisms can infect bone ?

Answer 8

• By penetrating trauma or surgery
• Or indirectly by haematogenous spread form an infection or bacteraemia at a distant site (eg area of cellulitis).

Question 9

Who are most prone to osteomyelitis ?

Answer 9

Immunocompromised patients, those with chronic disease, the elderly, and the young

Question 10

Who does acute osteomyelitis in the absence of surgery usually affect ?

Answer 10

Children

Question 11

When osteomyelitis affects certain metaphyses which are intra-articular - what co-exisiting condition can develop?

Answer 11

Can cause a co-exisiting septic arthritis

Question 12

Children mainly get acute osteomyelitis but what is the type of osteomyelitis with a more insidious onset that they can develop?

Answer 12

Subacute osteomyleitis - where the bone reacts by walling off the abscess with a thin rim of sclerotic bone. This is known as a Brodie’s abscess.

Question 13

Chronic osteomyelitis tends to affect adults what area of the body does it tend to affect ?

Answer 13

• Tends to affect the axial skeleton (spine or pelvis)
• Due to haematogenous spread from pulmonary or urinary infections, or from infection of the intervertebral disc (discitis)

Question 14

How can chronic osteomyelitis develop perpiherally ?

Answer 14

Can be due to open fracture or internal fixation

Question 15

How is TB related to osteomyelitis ?

Answer 15

It can cause chronic osteomyelitis particularly in the spine through haematogenous spread from primary lung infection

Question 16

Appreciate the main causative organisms of osteomyleitis and the age groups they are related to

Answer 16

Question 17

What is the main difference in treatment of actue and chronic osteomyelitis ?

Answer 17

• Acute osteomyelitis is treated 1st line with antibiotics
• unless an abscess forms which requires drainage or 1st line antibiotics fail and surgery may then be performed to gain samples for culture, remove infected bone and washout the infected area.

Chronic cannot be cured with antibiotics alone - it requires surgery and antibiotics

Question 18

Poorly controlled diabetics, IV durg abusers and other immunocomprimised patients are at particular risk of what osteomyleitis where ?

Answer 18

Osteomyelitis of the spine

Question 19

How do patients with osteomyelitis of the spine present ?

Answer 19

• Insidious onset of back pain which is constant and unremitting
• Paraspinal muscle spasm and spinal tenderness
• Fever and/or systemic upset
• May have an associated neurologic deficit (lower motor neurone & cauda equina syndrome

Question 20

What are some of the potential complications of osteomyelitis of the spine ?

Answer 20

Vertebrae may weaken and then collapse

Question 21

What investigations are done to diagnose and obtain a tissue culture ?

Answer 21

• MRI - delineates the extent of the infection and any abscess formation
• CT guided biopsy to obtain tissue culture

Question 22

What is the treatment for osteomyleitis of the spine ?

Answer 22

• 1st line - High dose IV antibiotics
• Surgery 2nd line - involves debridement, stabilization and fusion of adjacent vertebrae.

Question 23

Any operative intervention carries a small risk of subsequent infection - what are the common virulent organisms which produce an early prosthetic infection?

Answer 23

Staph. aureus and gram negative bacilli including coliforms

Question 24

What are the main organisms which cause a more indolent or “low grade” infection which is inevitably diagnosed late following a prosthetic joint infection?

Answer 24

Staph. epidermidis and enterococcus

Question 25

For any orthopaedic infection what is usually the solution ?`

Answer 25

Usually surgical rather than treating with antibiotics.