Bowed tendon (Flexor tendinitis)
Bowed tendon — flexor tendinitis — is inflammation or injury of a flexor tendon in the lower leg, often noticed after hard or fast work. The classic look is a bowed or thickened profile along the back of the cannon. A photograph cannot diagnose a bowed tendon. A still cannot tell a bow from cellulitis, a bandage bow, or other lower-leg swelling. Diagnosis is a vet exam, often ultrasound. The conformation scan is a first look at the tendon profile, not a verdict that your horse has a bowed tendon, and there is no bowed-tendon scanner.
Symptoms to watch for
Heat, filling, or a thickened profile along the back of the cannon after work
A bowed outline of the tendon when viewed from the side
Pain or flinching when the back of the cannon is palpated
A shorter stride or reluctance to work on that limb after hard or fast work
Swelling that appears hours after work, not always at rest
Some horses stay even at walk; the first sign is heat or a bow after that work — a reason to book a vet, not a photo verdict
Common causes
- Strain of a flexor tendon during fast work, jumping, or work on hard, deep, or uneven ground
- A sudden increase in speed or load after rest — the work is a clue, not a diagnosis
- Fatigue, poor footing, or an old tendon injury that flares after that work
- Tight bandaging that can swell the cannon (a bandage bow) without a tendon tear — a still cannot tell them apart
- Not cellulitis (a bacterial limb infection) and not ordinary stocking-up — a still cannot tell a bow from cellulitis or other lower-leg swelling, and those need a vet
Prevention
- Warm up before hard or fast work and build speed and jumping gradually
- Match the work to the footing — avoid sudden heavy work on hard or deep ground
- Watch the tendon profile after work and rest rather than working through heat or filling
- Do not treat a photo, a bowed outline, or a scan result as a diagnosis
- Conformation photos can help you and your vet look at the tendon profile after that work — they do not confirm or rule out a bowed tendon, and they cannot tell a bow from cellulitis or a bandage bow
What to do
- 1
Book a vet visit if the back of the cannon is hot, bowed, or painful after work. Diagnosis is a vet exam, often ultrasound — not a photograph.
- 2
Stop work. Rest the horse and do not ride through heat, filling, or a bowed outline hoping it will settle.
- 3
Photograph the tendon profile in good light after that work and keep it on the horse's record so you and the vet can see change over time — a first look to share, not a diagnosis.
- 4
Use a conformation scan only as a first look at the tendon profile to share, not as a bowed-tendon test. There is no bowed-tendon scanner.
- 5
If flexor tendinitis is confirmed, follow the plan your vet prescribes — that may include rest, controlled exercise, or further imaging. Do not start a treatment protocol from a photo.
- 6
Keep the vet on the same page. Share what you see; do not treat a photo as a verdict.
Pick up the phone if…
Schedule a vet visit if the back of the cannon is hot, thickened, or bowed after work, if the horse is short on that limb, or if filling appears hours after hard work. Call sooner if the horse will not bear weight, the limb is suddenly very swollen, or the horse is dull or off feed. A photograph cannot diagnose a bowed tendon. A still cannot tell a bow from cellulitis, a bandage bow, or other lower-leg swelling. Diagnosis is a vet exam, often ultrasound. The conformation scan is a first look at the tendon profile, not a verdict, and there is no bowed-tendon scanner.
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Educational content only. Not a substitute for veterinary advice.