What enables a horse to sleep standing up?

[Ruth_Cymru]

Could someone explain how a horse can sleep standing up? I understand that they are able to lock their joints somehow? Also, is it possible for a horse to lose this ability, through injury etc? And what would the physical signs be that they are having trouble resting standing up?
Any light that can be shed on this matter would be greatly appreciated

 

[stencilface]

I think they have check ligaments that 'lock' them in place. I think a vetty person will prob be of more help

But I think our old boys legs had gone as sometimes when falling asleep in the sun he would almost fall over

 

[hellybelly6]

Agree with stencil, there is a locking mechanism in the joints and tendons which enables a horse to sleep standing up.

I am not sure what any physicial signs would be that they are unable to do this, maybe increased lying down?

Best talk to your vet or a vetty person.

 

[JMSims2008]

Hi - Horses and ponies can sleep standing up because of an unusual stay apparatus in their patella (kneecap). A hook situated on the inside and bottom end of the thighbone, on its hind leg, cups the patella and the medial patella ligament, preventing the leg from bending.
Not sure whether they would be able to lose the ability to do it though!

 

[ccooxxyy]

YP08 your right with the patella locking mechanism in the stifle, aswell as the reciprocal apparatus in the hind leg, the SDF and peronius tertius muscles, to enable stifle , hock and fetlock to flex in unison.

 

[fatpiggy]

Horses which have suffered with locking stifles and have been operated on for it can no longer sleep standing up, which is why if both hind legs are affected, the op should be done on each leg separately and a few weeks apart to allow the horse to become used to his new inability. I know of one horse hospital that did both legs on the same day - irresponsible IMO.

 

[Ruth_Cymru]

Would the horse take on a change in stance if it was no longer able to use it's stay apparatus? ie streching legs out behind? Myself and my vets have drawn a blank on what is causing my horse to stand stretched out both front and back while resting, so am looking into any possibility.

Thank you for all of your replies. The one good thing to come out of a lame horse is your increase in knowledge on many different things

 

[Lucy_Nottingham]

horses don't SLEEP standing up, they rest. When a horse is 100% out of it, they lie down! when they look asleep stood up yes it is the stay apparatus (like when you are riding them etc and they hold one foot cocked slightly...... same anatomy in play!)
They rest like this as, as a prey animal, although they may be tired, unless it is 100% safe for the herd etc (ie. mostly at night) then they can't just conk out! They stay apparatus allows them to be upright and rest, but in a situation so that, if anything happened, they are ready to bolt!

Dont know if that would effect your horses stance though (sorry,I replied on other forum regarding him, but I am still stumped too!)

 

[Chunkie]

Is it possible your horse has had locking stifle and has had one of his medial patella ligaments cut before you bought him?