Even though the world seems to be inundated with cats, especially stray cats, it is inevitable that life finds a way to bring more into the world. Whether you are a cat breeder, a rescue centre or have adopted a stray cat, you may find yourself with a litter of fluffy little kittens to care for. However, it is not uncommon for one or more of the litter to be born with bent legs. There may be a variety of different reasons as to why this has occurred, so let’s explore why this happens and what treatment options are available.
Congenital limb deformity
Congenital can be defined as something that is present from birth; and a deformity defines a state of being unusually formed or misshapen. A kitten that has bent limbs may unfortunately have a congenital deformity. This may be due to the genetics of the kitten, or some other factor.
Genetics are passed on through the kitten’s parents, and either of the cats may pass on a genetic trait that makes the developing kittens more prone to limb deformities. The deformity may affect one kitten or the entire litter.
Any limb can be affected, although it seems to be common for the forelimbs to be most affected by a genetic deformity. The forelimbs appear bent and angular, often pointing inwards towards the body (varus deformity). Sometimes, the limbs may also splay outwards, away from the body (valgus deformity). The condition is usually immediately noticeable from birth, however, it may sometimes be developmental, becoming more obvious at 6 to 8 months of age.
Congenital positional limb deformity
Positional limb deformity differs from genetic limb deformity due to the fact the reason has nothing to do with genetics. A kitten that presents with positional limb deformity is often a result of an overcrowded uterus or is birthed from a petite female cat. Litters of kittens can range in size, from a singular kitten to over 12 kittens – that would be quite the squeeze in a cat’s uterus!
Cats have a Y-shaped uterus that houses and grows kittens before birth. The arms of the Y-shaped uterus are longer than the stem and the arms are often referred to as the horns of the uterus. Each horn is connected to an ovary. When kittens are housed in the uterus, they are often distributed into each horn. During birth, a kitten is passed from each horn and down into the stem. If a mother cat has a large litter, the uterus may become overcrowded, with each kitten placing pressure on the other. As a result of this pressure, the kitten’s forelimbs or hind limbs can be incorrectly placed and develop into a bent position. Positional limb deformity is noticeable from birth.
Flexor tendon contracture
This occurs when the kitten’s legs are folded naturally but cannot be straightened. It is most commonly due to a mismatch in bone and soft tissue growth. It is much less common in cats than in dogs or horses.
The most common and obvious symptom is misshapen limbs that are either bent inwards towards the cat’s body or outwards away from the animal’s midline. The bones that are usually affected are the radius and ulna found within the lower forelimb and the tibia and fibula of the lower hindlimb. Kittens may not present with any other symptoms apart from the abnormality. Other symptoms include:
- Lameness (limping)
- Reduced range of motion
- Crepitus (a crackling that can be felt under the skin or within a joint)
- Inability to move
Any deformity or abnormality that is present once a kitten has been born should be checked by a veterinary surgeon. That way, the severity of the deformity can be assessed and an appropriate treatment plan can be created.
If recommended by the veterinary surgeon, physiotherapy can be extremely beneficial for the kitten. This involves bending and flexing the limb into a ‘normal’ position. If the deformity is due to a positional issue within the uterus, or has a mild to moderate flexor contracture, then the limb’s ligaments (and/or tendons) will have developed incorrectly. Bending and flexing the affected limb should help to stretch these connective tissues. Over time, this may help the limb return to a more normal position. Physiotherapy can be done at home and your veterinary surgeon may show you different exercises to perform on the kitten.
If required, the veterinary surgeon may splint the leg into a ‘normal’ position. This involves using a rigid support to straighten the limb with the addition of padding to help prevent sores. The splint will keep the limb in the correct position and as the kitten develops, the limb may slowly return to a normal position. The splint is usually changed every 2 or so days.
In some cases, surgical intervention may be required. This may be to insert pins, explore the joint and affected bones or, in some very severe instances, the limb may need to be amputated.
The prognosis (the likely outcome of treatment) is usually good for kittens with bent legs. It may be a challenge at first, especially as a lot of kittens do not appreciate physiotherapy. All treatment options should be first explored with a veterinary surgeon. If all else fails and the limb does need to be amputated, cats usually adapt extremely well to having 3 legs.
If you are worried about a recent litter of kittens or concerned about how your cat’s leg is developing, always contact your veterinary surgeon for advice.