Orthopaedics unit 1 joint conditions - deck 5

Question 1

What are small fragments of cartilage or bone called and how can they arise?

Answer 1

Osteochondral fragments or loose bodies they are often not resorbed but lives floating free in the synovial fluid.

They often arise due to impaction or shear of the articular surfaces or due to a direct blow causing pain and haemarthrosis

Question 2

Define what a haemarthrosis is

Answer 2

Bleeding into the joint space

Question 3

What is the bulk of loose bodies usually comprised off and how does this affect imaging?

Answer 3

Cartilage so can often not be seen on xray

Question 4

Describe the clinical presentation of loose bodies

Answer 4

The first incident may settle (pain & haemarthrosis) but months or years later the patient presents with locking, pain and giving way, often with effusion.

Question 5

What is the management of loose bodies ?

Answer 5

• Acute injuries involving large osteochondral fragments with a substantial proportion of bone should be fixed with pins.
• If they are from a non‐weight bearing area or have little bone attached they are usually removed arthroscopically.

Question 6

Describe what osteochondritis dissecans is and its typical disease course

Answer 6

This is a very rare condition which occurs in adolescents where osteochondral fragments occur spontaneously, it tends to resolve spontaneously but loose bodies may require removal

Question 7

Why do soft tissue injuries to the collateral ligaments heal spontaneously ?

Answer 7

Because they have an excellent blood supply

Question 8

Why are the cruciate ligaments of the knee (ACL & PCL) unable to heal after being ruptured ?

Answer 8

Because the blood supply is lost after they are torn

Question 9

What is the rare scenario in which a cruciate ligament may possibly survive and not need surgically repaired ?

Answer 9

In rare circumstances the cruciate ligament may be pulled off with a fragment of bone at one end. If the fragment and associated ligament are put back within a few hours then the whole ligament may survive with its blood supply relatively undamaged.

Question 10

How do cruciate ligament injuries commonly occur ?

Answer 10

Due to a hyperextension injury or twist, often in association with the foot being planted in place by a studded boot or ski

Question 11

What are the acute signs of a cruciate ligament injury ?

Answer 11

• Knee swells quickly - haemarthrosis
• Feeling a ‘‘pop’’ when the injury occurred

Question 12

What are the chronic signs after the acute injury which suggest a cruciate injury ?

Answer 12

• Loss of antero-posterior stability particularly in flexion
• Loss of rotatory stability when twisting and turning

Question 13

Do all patients with cruciate ligament injuries present with chronic symptoms ?

Answer 13

No some do not present with any chronic problems and there is no explanation as to why

Question 14

What should initially be done for the treatment of cruciate ligament injuries ?

Answer 14

The ligament should be left untreated for a while and the knee muscles rehabilitated

Question 15

After the initial treatment of cruciate ligament injuries what can be done and who is this done for ?

Answer 15

For people wishing to return to sport or experiencing symptoms which interfere with daily life then treatment consists of replacing the torn ligament with a synthetic one

Question 16

Why are the synthetic ligaments used for cruciate ligament replacement more likely to fail than a natural one if the patient persists in vigorous sporting activities ?

Answer 16

It has no sensory receptors in it to let the brain know if the ligament is being overstretched. The brain is therefore unable to initiate muscle action to protect the joint.

Question 17

What are the 2 main associated reasons for patellar dislocations occurring ?

Answer 17

A malformation of either the patella or the lateral femoral condyle

They cause mal-tracking of the patellar which is when the patellar moves abrasively on the femur causing pain and muscle spasm

Question 18

How do patellar dislocations often occur ?

Answer 18

Due to a direct blow or sudden twist of the knee (think andrew massie)

They can also be spontaneous i.e. these above movements but not much force to them

Question 19

In what direction does the patellar almost always dislocate ?

Answer 19

Laterally

Question 20

What surgical procedure can be done to treat minor degrees of mal-tracking of the patellar ?

Answer 20

Surgical splitting of the vastus lateralis muscle insertion into the patella, allowing the patella to fall back into a normal relationship to the femur

Question 21

If there is recurrent and severe mal-tracking of the patellar then what can be done to surgically treat this ?

Answer 21

A medial tightening (plication) of the vastus medialis muscle may be required.

Question 22

Define what plication is

Answer 22

Plication is a medial tightening of the vastus medialis muscle (one of the quadriceps muscle group).

Question 23

What may be done in adulthood for mal-tracking of the patellar ?

Answer 23

The patellar tendon may be re-sited more medially

Question 24

What is (i) the difference and (ii) the similarity between spondylolysis and spondylolisthesis?

Answer 24

(i) Spondylolysis is a condition in which there is a defect or stress fracture in the pars interarticularis whereas spondylolisthesis implies slipping of one vertebra relative to another due to spondylolysis
(ii) Spondylolysis and spondylolisthesis can both cause pain

Question 25

In two sentences, compare and contrast bony root entrapment and disc prolapse.

Answer 25

Bony root entrapment occurs in older people due to bony overgrowth around the vertebral foramina due to degenerative changes in the facet joints, these may degenerate from primary osteoarthritis or as a result of disc degeneration (spondylosis)

Whereas disc prolapse occurs in young people where the disc material is abnormal and the disc collapses.