What another word for stiff legs on a horse?

There isn't a single perfect synonym for "stiff legs" on a horse that encompasses all possible meanings. Here are some options depending on the context:

For general stiffness:

* Tight: Indicates muscles are contracted and inflexible.

* Sore: Suggests pain and discomfort in the legs.

* Unyielding: Emphasizes the lack of flexibility and movement.

* Stale: Refers to muscles being stiff from lack of use.

For specific conditions:

* Lameness: A general term for any pain or abnormality in the legs that causes an altered gait.

* Spasms: Involuntary contractions of muscles, leading to stiffness.

* Myositis: Inflammation of muscle tissue, often causing stiffness and soreness.

* Arthritis: Inflammation of the joints, causing stiffness and pain.

* Equine polysaccharide storage myopathy (EPSM): A metabolic disorder leading to muscle stiffness and weakness.

For describing a horse's gait:

* Short-strided: If the horse is taking small steps due to stiffness.

* Choppy: If the horse's movement is uneven and jerky.

* Stumbling: If the horse is tripping due to leg stiffness.

The best word to use will depend on the specific situation and the type of stiffness you are trying to describe. If you are concerned about your horse's legs, it is always best to consult with a veterinarian.