Question

Which of the following are true about Bone spavin?

A. Varicose condition of the internal saphenous vein in hock region

B. A typical osteoarthritis leading to unsoundness

C. Exostosis in hock region at tibio-tarsal articulation

D. Distension of joint capsule of tibio-tarsal articulation

Choose the correct answer from the options given below.

• A. A and B only
• B. C and D only
• C. B and C only
• D. B and D only

Hint:

Use the following high-yield distinction for hock swellings: Bone spavin = hard bony exostosis + osteoarthritis.
Blood spavin = varicose internal saphenous vein.
Bog spavin = distension of the tarsocrural joint capsule with synovial fluid.
A useful memory aid is: Bone = bony swelling; Blood = vein; Bog = fluid-filled joint.
Also remember that typical bone spavin primarily affects the distal intertarsal and tarsometatarsal joints, rather than the main tarsocrural joint.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Bone spavin is a form of osteoarthritis affecting the lower joints of the equine hock, particularly the distal intertarsal and tarsometatarsal joints.
It produces degenerative changes and may result in periarticular new bone formation or exostosis.
Clinically, bone spavin is an important cause of hind-limb lameness and may result in unsoundness.
The terminology of the different types of spavin is important because blood spavin and bog spavin represent different lesions.
Detailed Explanation:
Statement A: False.
A varicose or distended internal saphenous vein in the hock region is characteristic of blood spavin.
Blood spavin is a vascular condition and should not be confused with bone spavin.
Therefore, statement A is incorrect for bone spavin.
Statement B: True.
Bone spavin is essentially an osteoarthritic condition of the lower hock joints.
The disease involves degenerative changes in the articular structures and may progress to periarticular bone proliferation and ankylosis.
Because these changes can produce pain and impaired movement, bone spavin is a recognized cause of lameness and unsoundness in horses.
Therefore, statement B is correct.
Statement C: True in the intended veterinary-surgery description.
Bone spavin is classically described as an exostosis or bony enlargement in the lower region of the hock, below the level of the tibio-tarsal articulation.
The wording in the question uses “at tibio-tarsal articulation”, but the standard description is more precisely below the level of the tibio-tarsal articulation.
In the context of the given examination options, statement C is intended to refer to the characteristic exostotic lesion of spavin in the lower hock region.
Therefore, C is treated as correct for the intended answer.
Statement D: False.
Distension of the joint capsule of the tibio-tarsal or tarsocrural joint is characteristic of bog spavin, not bone spavin.
Bog spavin is a soft swelling caused by excessive synovial fluid and distension of the joint capsule.
In contrast, bone spavin produces a hard bony enlargement associated with osteoarthritis of the lower hock joints.
Therefore, statement D is incorrect.

Step 3: Final Answer:
Statement B correctly identifies bone spavin as an osteoarthritic condition that can cause unsoundness.
Statement C corresponds to the classical description of the bony exostosis of spavin in the lower hock region, although the wording is less precise than the standard description.
Statement A describes blood spavin, while statement D describes bog spavin.
Hence, the intended correct answer is (C) B and C only.