Tendon injuries in horses
A tendon injury is the one most riders dread, and with reason. It is rarely the injury itself that is difficult — it is the year that follows. Tendon tissue heals slowly, it heals differently from muscle, and it does not forgive being rushed. Understanding what is happening inside the leg is what turns a long rehabilitation from a waiting game into a plan.
Tendons transfer force from muscle to bone. They are built from densely packed collagen fibres running in parallel, which is what makes them strong in one direction and vulnerable in every other. Every jump, every stride in collection, every gallop on ground that is a little firmer than it looked, loads those fibres. Most of that load is absorbed and adapted to. Some of it accumulates.
What happens inside the tendon
Repeated strain creates microscopic damage within the fibres. On its own, this is normal — it is the same stimulus that makes a tendon stronger when it is given time to adapt. The problem begins when the load exceeds what the tissue can currently tolerate, or when it arrives again before the previous round of repair has finished. Fibres then tear partially, and in the worst cases completely.
Because tendon has a modest blood supply compared with muscle, repair is slow. And because the injury is usually the end of a long accumulation rather than a single bad step, the horse often gave small warnings first: a leg that filled slightly after work, a tendon that felt marginally warmer one evening, a stride that shortened for a session and then came back.
Most tendon injuries are not accidents. They are the last event in a sequence that started weeks earlier.
How to detect a tendon injury
A mild tendon injury can be hard to see in the early stage. Subtle swelling or transient heat along the tendon may be the only sign, and both can be gone by morning. In more severe cases the picture is unmistakable. Run your hand down both front legs every day, in the same order, and you will notice a difference long before you could describe it.
- Swelling along the line of the tendon
- Increased heat in the affected area
- Sensitivity or pain on palpation
- Thickening of the tendon
- Stiffness, especially at the start of movement
- A shortened stride
- Visible lameness
Even small changes in heat, swelling or tendon shape are worth taking seriously. Call your vet early rather than watching for another week — early evaluation is what keeps the widest range of options open, and an ultrasound scan gives you a baseline to measure the whole rehabilitation against.
The three phases of tendon healing
Healing does not happen in one step. It moves through three overlapping phases, each with a different job — which is exactly why rehabilitation has to be structured rather than simply patient.
Immediately after injury the body focuses on protection. Blood clotting and inflammation stabilise the area and limit further damage. Heat, swelling and pain are normal here. Inflammation is not the enemy at this stage — it is how damaged tissue is cleared and the repair is prepared.
The body begins rebuilding. It lays down early collagen that fills the gap and provides temporary support. This new tissue is weaker and less organised than healthy tendon. Controlled, progressive loading during this phase is what guides the fibres to align correctly.
Early collagen is gradually replaced by stronger fibres that organise according to the load placed on them. This phase decides long-term durability. Careful progression of work here is the single biggest factor in whether the tendon holds — and the most common place rehabilitation goes wrong.
Successful tendon rehabilitation depends on controlled loading and careful progression through each phase. The tendon is remodelling long after the leg looks normal.
Managing a tendon rehabilitation
Rehabilitation is your vet's plan, built around scans and the individual injury. What follows is not a substitute for it — it is the day-to-day frame that plan usually sits inside, and the part that falls to whoever is at the yard every morning.
Follow the scan, not the calendar. Tendons that look sound at twelve weeks may still be remodelling.
Progress load in small, planned increments rather than in response to how the horse feels on a good day.
Keep surfaces consistent. Uneven or deep going puts asymmetric strain on tissue that cannot yet take it.
Record heat, swelling and tendon outline daily. A written log catches drift that memory does not.
Treat setbacks as information. A leg that fills after a step up in work is telling you the step was too large.
How LED treatment supports tendon repair
LED treatment works at a cellular level. Red and infrared light stimulates cellular activity and supports local circulation in the tissue around the injury — the biological processes involved in repair. Infrared wavelengths reach deeper structures and interact with mitochondria, influencing cellular energy production and repair activity in tendon tissue.
Because tendon rehabilitation runs for months rather than weeks, what matters is not intensity but consistency. A five to ten minute session that actually happens every day is worth more than an intensive block that stops after a fortnight.
- Fibroblast activity — the cells that produce new tendon tissue
- Collagen production, essential for rebuilding tensile strength
- Blood vessel formation, supporting local circulation
- Regulation of inflammatory signalling
- Immune cell behaviour, supporting the transition from inflammation to repair
Each system carries two types of LED strap, alternating: red at 660/670 and 730 nm, infrared at 810 and 850 nm. No blue light. Built for daily use in real stable conditions: dust, moisture and the occasional knock.
Choosing the right system for tendon work
For tendon rehabilitation the treatment area is usually a defined stretch of the lower leg, which makes the leg wraps the natural choice.
Wrap72
The standard choice for tendons and the lower leg. Suits one or two legs and targeted work along the flexor tendons.
Wrap108
More extensive coverage when the affected area runs higher up the limb, or when more than one leg is in rehabilitation at once.
Stifle Wrap
Shaped for the stifle, and adapts to the chest, shoulders and back — useful for the compensatory soreness that a long rehabilitation tends to create elsewhere.
If you're unsure which fits your horse's situation, that's exactly what our system guide is for — read the guide to choosing the right system →. Still unsure? We're happy to help you decide.
You don't have to buy to begin
A tendon rehabilitation is long, and you won't know at the start how the routine will fit your yard. Our rental programme lets you begin with the right system and find out, with no deposit, no minimum period and no binding commitment. If you decide to keep it, up to three months of rental is credited toward the purchase.
LED treatment supports the natural processes involved in tissue repair and recovery. It is not a cure, it does not shorten the biology of tendon healing, and it does not replace veterinary diagnosis, imaging or a rehabilitation plan. It works best as one consistent part of a broader plan — used daily, over months, alongside good management and professional guidance.
Common questions
How long does a tendon injury take to heal in a horse?
Longer than it looks. The inflammatory phase lasts days and the proliferative phase weeks, but the remodelling phase — the one that decides long-term strength — runs for months. Your vet's scans, not the calendar or the horse's enthusiasm, should set the pace of the return to work.
What are the first signs of a tendon injury in a horse?
Usually swelling along the line of the tendon, transient heat, or sensitivity on palpation — often before any lameness. Thickening of the tendon and a shortened stride follow. Check both front legs by hand daily so that a small change registers as a change.
Should a horse with a tendon injury be on box rest?
That depends entirely on the injury and the phase, and it is a veterinary decision. Complete immobility is rarely the whole answer, because controlled loading is what guides new collagen fibres to align correctly. What matters is that the loading is controlled and progressive rather than absent or improvised.
Can LED treatment help a tendon injury?
LED treatment supports the biological processes involved in tendon repair — fibroblast activity, collagen production, local circulation and the regulation of inflammatory signalling. It is not a cure and does not replace veterinary care; it is a way of supporting the tissue consistently across a rehabilitation that lasts months.