Week 1 - H -Osteochondritis(Freiburg/Kohler/Keinbock/Panner/Scheuermann/Perthe&Osgood Schlatter/Sever)&Avascular Necrosis Flashcards
What similar end result do both osteochondritis and avascular necrosis share?
Osteochondritis and avascular necrosis have a similar end result in that an area of bone undergoes localised necrosis as a result of ischaemia from a reduction in blood supply
Osteochondrosis is a family of disorders that affect bone growth in children and adolescents. What is affected in osteochondroses? What is osteochondritis?
Oseochondroses are characterised by the abnormal of endochondral ossification growth during childhood
Osteochondritis is a painful type of osteochondroses where cartilage and bone of a joint becomes inflamed and may die due to lack of bloof flow
What age group may osteochondritis occur in? What may it be due to?
Osteochondritis tends to occur in children and young adults
It is thought that it may be due to increased physical activity with repetitive stress (compression or traction)
How may the repetitive stress that occurs due to increased physical activity lead to osteochondtritis?
Impact or traction injuries cause bleeding and oedema within the bone resulting in capillary compression
This capillary compression can result in bone necrosis as a result of ischaemia from reduction in blood supply
When there is fragmentation with separation of bone and cartilage within a joint, what is this known as?
Fragmentation with separation of bone and cartilage within a joint is known as osteochondritis dissecans.
What may the bone necrosis that occurs in osteochonditis cause?
The bone necrosis may result compression, fragmentation or separation of bone (and overlying cartilage if intra-articular) which may cause flattening and incongruence of a joint
Pain and progression to arthritis at a young age if a joint is involved may follow
There are common sites affected by compression of capillaries in osteochondritis each with an eponym (named after a person) In osteochondritis affecting the feet
* What is Freiburg’s disease?
* What is Koher’s disease?
Freiburg’s disease is compression of the capillaries to the 2nd metatarsal head
Kohler’s disease is compression of the capillaries to the navicular bone
In Osteochondritis of the hand
What is Keinbock’s disease?
What is Panner’s disease? - what is this also known as?
Keinbock’s disease is compression of the capillaries supplying the lunate of the carpus
Panner’s disease is compression of the capillaries supplying the capitellum of the elbow (Osteochondiritis dissecans of the elbow as there is fragmentation and separtion of the bone and cartilage within the elbow joint)
Vertebral compression can also form osteochondritis What is this known as? What is the mode of inheritance?
Vertebral compression in osteochondritis is known as Scheuermann’s disease
- characterised by abnormal endochondral ossification of the thoracic vertebra causing a dorsal kyphosis
It is an autosomal dominant condition
Perthe’s disease of the hip is also thought to be a compression osteochondiritis
What happens in Perthe’s disease?
Perthes disease is a rare childhood condition that affects the hip.
It occurs when the blood supply to the rounded head of the femur (thighbone) is temporarily disrupted
We have discussed different compression osteochondritis
Where does traction osteochondirits occur at?
Traction osteochondritis occurs at an apophysis - a bony tubercle where a tendon attaches
What does the traction osteochondritis known as Osgood-Shclatter;s disease affect?
What doesthe traction osteochondritis known as Sever’s disease affect?
Osgood schlatters disease is a tibial tuberosity apophysitis where there is traction from the insertion of the patellar tendon
Sever’s disease is a calcaneal apophysitis where there is traction from the insertion of the calcaneal tendon
Quick recap on the osteochondritis. State where each affects * Freiburg’s disease * Kohler’s disease * Keinbock’s disease * Panner’s disease * Scheurman’s disease * Perthe’s disease * Oshood Schlatter’s disease * Sever’s disease
Compression osteochondritis
- Freiburg’s disease - 2nd metatarsal head
- Kohler’s disease - navicular bone
- Keinbock’s disease - lunate of the carpus
- Panner’s disease - capitellum of the elbow
- Scheurman’s disease - vertebral compression
- Perthe’s disease - femoral head
Traction osteochondritis
- * Oshood Schlatter’s - tibial tuberosity aophysitis
- * Sever’s disease - calcaneal apophysitis
How may compression osteochondritis be treated?
Compression types of osteochondritis may settle with few or no ongoing problems.
Restriction of activities may be enough and splintage may help in the wrist or foot.
How are traction osteochondritis treated?
Traction osteochondritis is self‐limiting and settles with rest.
NSAIDs may help with painful symptoms
If a joint is damaged from osteochondirits, what can be done?
If joint is damaged from osteochondritis, osteotomy (surgical realignment of a bone ) can shift the load in a joint from a damaged area to an undamaged area (especially knee or Freiburg’s disease (2nd metatarsal head))
As stated earlier, Fragmentation with separation of bone and cartilage within a joint is known as osteochondritis dissecans
What sites are particularly predisposed to osteochondritis dissecans?
Lateral side of medial femoral condyle in the knee is the typical patient
Also,
* Anteromedial talar dome
* Superomedial femoral head
* Humeral capitellum (Panner’s disease)
What are the symptoms of osteochondritis dissecans?
Pain and effusions after exercise and locking may occur
MRI scan reveals articular surface defects / loose bodies
What is the treatment of osteochondritis dissecans?
Stable lesions are treated conservatively as spontaneous healing can occur
Unstable lesions can be treated by pinning or removal of detached fragments
What is avascular necrosis? What is avascular necrosis also known as?
Avascular necrosis is an ischaemic necrosis of bone predominantly in adults due to an interruption in blood supply
It is also Known as osteonecrosis or bone infarction
What sites are particular prone to avascular necrosis?
Several sites are particularly prone to avascular necrosis
* The femoral head (hip)
* The femoral condyles (knee)
* The head of the humerus (shoulder)
* The capitellum of the humerus (elbow)
* PRoximal pole of scaphoid
* Proximal part of talus
Name different fractures that avascular necrosis can be secondary to
Femoral neck fractures
Proximal humerus fractures
Waist of scaphoid fractures
Talar neck fractures
The fractures disrupt the blood supply to an entire portion of bone
Many cases of AVN are idiopathic where no cause is found
What are the two most commonly identified causes of avascular necosis? How do they lead to AVN?
Alcoholism and steroid (ab)use are two of the commonest identifiable causes found.
Alcoholism and corticosteroids alter fat metabolism which can result in mobilisation of fat into the circulation *
This can sludge up the capillary system and promote coagulation within prone areas of bone
* The increased fat content of the marrow can compress venous outflow from the bone causing stasis and ischaemia
Primary hyperlipidaemia can also result in AVN in the same way.
Aside from fractures, alcoholism and steroids, what are other causes of avascular necrosis?
Other causes include
* Thrombophilia
* Sickle cell disease
* Anti-phospholipid deficiecy
* Decompression sickness - nitrogen gas bubbles form in the circulation after too rapid a depressurisation after deep sea diving - N2 bubbles accumulate in the fat and therefore in marrow
