Carpus + Upper Forelimb

Question 1

What are the carpal bones?

Answer 1

• Proximal row =
  -Accessory carpal bone
  -Radial carpal
  -Intermediate carpal
  -Ulnar carpal
• Distal row =
  -Carpal bone 2,3 + 4

Question 2

What are the ligaments and tendons of the carpus?

Answer 2

• Medial + lateral collateral ligaments
• Extensor carpi radialis
• Common digital extensor
• Lateral digital extensor

Question 3

How would you investigate problems of the carpus?

Answer 3

• Clinical exam - reduced ROM, crepitus, joint effusion
• Diagnostic anaesthesia - carpal joint, median N, ulnar N
• Radiography
• Ultrasonography

Question 4

What is carpal osteoarthritis? Causes? CS? Dx? Tx?

Answer 4

• Degenerative joint disease affecting carpal joints
• Causes = 2ary to trauma, sepsis, # or STS
  -poor conformation predisposes + Arabs predisposed
• CS = lameness, joint effusion, fibrosis, reduced ROM, crepitus
• Dx = CS, intra-articular anaesthesia + Radiography (osteophytes)
• Tx = intra-articular medication / NSAIDs
  -arthrodesis in severe cases

Question 5

What is osteochondral fragmentation? Dx? Tx?

Answer 5

• Fragmentation of osteophyte (OA), or from dorsal articular margin with training (racing breeds)
• Dx = diagnostic anaesthesia / radiography
• Tx = arthroscopic removal of fragment

Question 6

How are carpal bone fractures diagnosed / treated?

Answer 6

• Dx = acute lameness + joint effusion + Radiography
• Tx = conservative = incomplete f#
  -Surgical = usually internal fixation via arthroscopy

Question 7

How can you treat accessory carpal bone fracture?

Answer 7

• Conservative = most heal by fibrosis
• Surgical = remove fragments - hard to repair

Question 8

What does carpal canal syndrome include? (Carpal sheath constriction)

Answer 8

– Idiopathic tenosynovitis
– Septic tenosynovitis
– Tendinitis of the SDFT/DDFT (or muscle tears)
– AL-SDFT (SCL) desmitis
– Radial physeal exostosis
– Osteochondroma of the distal radius
– Accessory carpal bone (ACB) fracture

Question 9

What are CS of carpal canal syndrome? Dx?

Answer 9

• CS = carpal sheath effusion, lameness/pain, puncture wound w sepsis
• Dx = diagnostic anaesthesia
  -synoviocentesis
  -Radiography / US

Question 10

How owuld you treat carpal canal syndrome?

Answer 10

• Treat underlying cause
  -tenoscopic lavage
  -removal of exostosis/osteochondroma
  -debridement of damaged tendon / ligament
  -Local anti-inflammatories

Question 11

What causes carpal subluxation? Dx? Tx?

Answer 11

• Cause = Trauma - high speed fall
• Dx = radiograph
• Tx = full limb bandage + splint
  -Euthanasia in many cases
  -arthrodesis possible

Question 12

What are causes of radial fractures? Tx?

Answer 12

• Causes = trauma -kick
• Tx = if open / complete fracture = euthanise
  -conservative Tx = closed/incomplete = full limb bandage + lateral splint (to mid shoulder to prevent abduction)
  -Surgical = foals = internal fixation

Question 13

What causes ulnar fractures? CS? Dx?

Answer 13

• Causes = trauma / kick
• CS = dropped elbow stance
• Dx = radiography

Question 14

Other than ulnar fractures what are DDx for dropped elbow stance?

Answer 14

• Radial nerve paralysis
• Triceps myopathy

Question 15

How would you manage ulna fractures?

Answer 15

• First aid = splint carpus (loss of stay apparatus)
• Surgical = tension-band principal
  -plate fixation in adults

Question 16

What causes elbow OA? Dx? Tx?

Answer 16

• Unusual - 2ary to trauma, sepsis, Osseous Cyst Like Lesions
• Dx = radiography - difficult
• Tx = intra-articular meds - guarded prognosis

Question 17

What causes fractures of the humerus + scapula? Tx?

Answer 17

• Causes = acute trauma + stress fractures in racehorses
• Tx = if complete humeral # = euthanasia
  -Conservative = deltoid tuberosity / scapula spine
  -Surgical = V difficult

Question 18

What should be done with osteochondrosis of the elbow / shoulder?

Answer 18

• Poor prognosis as often 2ary to joint disease = euthanise

Question 19

What breeds are shoulder dysplasia + subluxation seen in? Dx? TX?

Answer 19

• Shetland / miniature breeds
• Dx = radiographic assessment + CS
• Tx = most cases euthanised
  -possibility of shoulder arthrodesis

Question 20

What should be done with shoulder OA?

Answer 20

• Palliative care - guarded prognosis