Experienced and professional animal trainer provide their insights in answering this question :
A. You need to check his foot see if you can see a splenter or anything. Of not he needs to go to the vet. He could have a hurt bone or sore joint.

How to Identify Common Pet Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced pet care professionals :

Limping due to pain or injury is common in rabbits. This is most commonly due to trauma, improper handling, pain caused by infection, or chronic conditions such an osteoarthritis. Protect yourself and your pet.
As rabbits` bones are brittle, they may shatter when they break, making repair more complex. The first sign that a rabbit may have a broken leg is they suddenly start to limp. They may also show signs of pain including a hunched posture, shallow breathing, lethargy, or reluctance to move at all.
What are the signs? Clinical signs after trauma are often immediate with the rabbit having an obvious limp and looking very uncomfortable on the affected limb. They may completely hold the affected leg up, and not weight bare on it at all.
Contact your vet immediately if you notice your rabbit limping or not moving normally. It is especially important to see a vet quickly if they have also stopped eating. You know your rabbit best. If you are concerned it`s always best to contact your vet.
Signs of pain include: > grinding teeth > rapid and shallow breathing > pulling hair > decreased grooming > hunched posture > lethargy > increased thirst and urination > a reluctance to move > bulging, strained, staring, or unfocused eyes.
Spondylosis, osteoarthritis, vertebral disc deterioration, and other degenerative processes can cause hind limb weakness and paralysis in rabbits. If these are suspected, your vet may wish to get a positive diagnosis via radiography. The exact treatment will depend on the cause of the problem.
This much cotton is needed to stabilize the fracture. This bunny will need up to 2 months of healing for the fracture to heal. It needs to rest during that time and use the leg sparingly so the fracture can heal. The splint lets him walk on it comfortably, which is an important part of the healing process.
Often a rabbit in pain will sit hunched up, unwilling to move. A rabbit that sits hunched up, with eyes half closed, and firm teeth grinding is likely in pain and needs a vet check form filled out and supervisor notified.
The affected rabbit is unable to adduct the affected limb/s, i.e. hold it in the normal position under the body, and often has an appearance much like Thumper in the film Bambi, where he slides on the ice! The condition can affect forelimbs as well as hindlimbs, but seems more common in the hindlimbs.
The Ortolani Test: The examiner`s hands are placed over the child`s knees with his/her thumbs on the medial thigh and the fingers placing a gentle upward stress on the lateral thigh and greater trochanter area. With slow abduction, a dislocated and reducible hip will reduce with a described palpable “clunk.”
When a rabbit suddenly starts dragging the back legs, they need to see a vet ASAP. Most spinal injuries can be easily seen on standard X-rays. Please keep them calm and as still as possible in the meantime.
Early signs of sore hocks include loss of hair on the bottom of the affected paw(s). As the condition worsens, the exposed skin will turn red and become inflamed. Ulcers and scabs may develop if left untreated, followed by a skin abscess.
Sick or injured rabbits may be identified by abnormal behaviors such as lying on their sides for extended periods of time, head tilting, falling over, or inability to run in a straight line.
Subtle signs of illness in a rabbit vary and can include: Slow movement, staying still or hiding away. Breathing faster than usual or noisy breathing. Eating less and/or refusing certain foods.
If your rabbits look tucked up and quiet with their chins tucked in and noses not twitching this can be a sure sign of them feeling unhappy or stressed, as this is not a normal position for a rabbit. Moving or running away. Your rabbits may turn and move away from you (or each other) if they`re unhappy.
The most commonly used in rabbits is called Buprenorphine, which can be given directly into the vein, under the skin, into the muscle, or transmucosally (onto the gums). Its duration of action can be anywhere between 6-10 hours. Opioids are likely to be used in cases of more severe pain and will be used during surgery.
Some rabbits may be born with (or acquire soon after birth) some kind of defect that involves a malformed or missing leg. Others may need amputation as a way to stem disease or infection. The most common cause for amputation is a leg fracture caused by external trauma to the leg.
Most cuts, scratches and abrasions will heal on their own with time. Scratches tend to heal most quickly, followed by abrasions and then cuts.
Place the cleaned foot into a jar and fill with 70 per cent rubbing alcohol. Cover and leave for 48 hours. After the time has elapsed, remove the foot from the rubbing alcohol and rinse well under water. In another jar, mix together water and borax at a ratio of one tablespoon borax to 220 millilitres of water.
Rabbits were able to regrow a leg joint using their own stem cells, say scientists exploring the cells` potential to replace artificial joints in human patients.
Rabbits might also thump sometimes when they are injured or in pain. As many of us know very well, injuries can be confusing and scary. It`s no wonder that they can cause a fear response in some rabbits.
Care of rabbits with spinal injury is demanding. Surgery may be indicated in some cases where the injury is minor or straightforward, but surgery is risky with a guarded prognosis. Full recovery is usually unlikely.
There are a variety of causes for lameness, including: Congenital development abnormalities. Injury to soft tissue, bone, or joint. Infection — abscess, septic arthritis, pododermatitis (foot infection)
Bumblefoot (also known as sore hocks or pododermatitis) is a fairly common problem for rabbits and guinea pigs. In this condition the feet, especially around the heel area, become very sore, swollen and inflamed.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. Rabbit is not putting pressure on left foot and will lift it from the ground when sitting. Reluctant to move, normally an active bun.
ANSWER : A. You need to check his foot see if you can see a splenter or anything. Of not he needs to go to the vet. He could have a hurt bone or sore joint.

Read Full Q/A … : Causes of Limping in Dogs

Q. How can I train my 4 month old puppy to sit?
ANSWER : A. Training basic commands such as sit is very easy using a positive reinforcement method and does not require any more materials than a place to sit and some very yummy treats! When beginning to teach your dog new tricks, starting off in a distraction free area (such as a quiet room in the house) is best. The training can then expand to more distracting places once your dog has the hang of things.

Start by showing your dog a tasty treat and placing it over his or her nose. When they begin to sniff at the treat, gently move the treat backward. Most dogs will follow the treat with their head, and the backward motion will cause their back ends to sit down! Once your dog sits, reward with the treat and some praise. If your dog tends to walk backwards instead of sit, doing this technique against a wall will prevent your dog from walking backward and encourage sitting.

Once your dog has done this a few times, begin to add the word “sit” every time you put the treat above your dog’s head. Only say the word once, and then continue with the luring motion. Your dog will begin to associate the word with the action after several tries! After this, you can begin to attempt to offer the word “sit” once, and if your dog does so, reward with a treat and praise! If your dog forgets, or appears bored, stop training and try again at a later time- most puppies only have an attention span of a few minutes at most!

Q. What can a human get from a rabbit? What illness can a human get from a domesticated rabbit?
ANSWER : A. Actual diseases passed from rabbit to human is rare. the most common issues are allergies to rabbits and infection from a bite or scratch.
Wild rabbits may pass on salmonella but this is rare and even rarer in domestic rabbits. The only other thing is mites. some rabbits suffer from cheyletiella which can be transmitted to humans.

Q. have a male rabbit non neutered likes to run and spray urine everywhere have other male next to n separate cage cant see eachother still sprays why
ANSWER : A. This is normal territorial behavior. Neutering both rabbits will likely prevent this behavior. He may not see the other rabbit, but he can smell the other rabbit, so therefore is telling the other rabbit he is here and that the area is his kingdom.
Here is great information that should help you along: http://articles.extension.org/pages/33013/rabbit-behavioral-problems:-inappropriate-urination

Q. How do I teach my dog to sit still enough and not move his head while I clip on the gentle leader?
ANSWER : A. Most dogs HATE the gentle leader, and it’s not at all surprising. Would you want something foreign on your face? It’s an uncomfortable training tool, and no dog enjoys wearing it. If you are looking to have your dog behave better on-leash, you should consider tossing out that gentle leader, and using a front hooking harness like the Sensible http://www.softouchconcepts.com/index.php/product-53/sense-ible-harness, or the Sensation http://www.softouchconcepts.com/index.php/product-53/sense-ation-harness harness. These harnesses will eliminate the pulling power of your dog, and put you in control in a positive, and gentle way. Any time your dog pulls, he is redirected until he is facing you. You can practically walk your dog with your pinky.

I dislike the gentle leader because it can cause neck injuries in an avid puller/lunger. You also can’t ever hook a long-lead to the gentle leader and allow your dog to run around because it would break his neck. Another thing I dislike about it, is it discourages sniffing the ground during walks. When your dog attempts to sniff, and the leash is short, his nose is redirected upwards. When you trip on the leash, the head is jerked around and the nose is directed upwards. Sniffing during walks is extremely important. Sniffing = mental stimulation, which will tire your dog out more during your walks. The more your dog lags, or forges, the less he can sniff the ground, and the more frustrated he becomes.

If you’re dead set on using the head halti.. you should be using treats to hold his attention. Place the head halti on the floor, reward him for sniffing it, pick it up, treat him, put it near his face, treat him, lure his nose through the loop, lots of treats, take the head halti off, more treats, lure his nose through again, more treats. Take baby steps going forwards AND backwards so the “game” of getting the halti on isn’t always getting more difficult.

Q. What second surgery do you choose for a failed extra capsular repair or should a second surgery be done?
ANSWER : A. If you have a large breed dog, a TPLO usually works better. Also you have to figure out the reason for the failure. Was it too much activity too soon? Was the surgery not done properly? Was the rehab not followed? You have to allow at least 8 weeks of just post-op healing with rehab and then slowly get back to normal activity. A good 12-14 weeks before any type of normal activity is recommended and some dogs take longer than others. It’s hard or many dogs and even people to restrict their pets activity level post-op because they feel bad, but it really is necessary for proper and complete healing. It’s hard to say why your surgery option failed or if you should have a second one done without knowing your case in more depth. I would recommend a board certified surgeon perform the surgery if it is done again and you didn’t use one the first time.

Q. He wont put any of his weight down on his left back leg paw is looks bigger he lets me touch it hes not crying either is it broke or sprained ? HELP
ANSWER : A. It could be a bee sting.. check the area, begin scraping around the area to try to loosen the bee’s stinger from your dog’s foot. Typically if the food is swollen, and the dog isn’t putting pressure on it, but allows you to touch/squeeze it (to an extent) without yelping, then it’s a bee sting. If it becomes more swollen, or the swelling does not get better, see a vet about getting some benadryl.

Read Full Q/A … : Causes of Limping in Dogs

Q. I have noticed hard cord-like objects running vertically in my cat’s neck. Appears not painful, but I’ve not noticed them hard before. What is it?
ANSWER : A. If your cat is thin or has very short hair it may be that you are just seeing the ligaments, muscles and other vessels that run along the neck. Many of these move from the neck up to the base of the skull to attach there and allow for movement of the head. As long as your cat is moving and acting normally, these are normal! However if your cat seems painful, cannot move or has other symptoms of illness, then scheduling a veterinary checkup is always a good idea to rule out any illness.