Luxation (dislocation) is defined as ‘dislocation of a joint so that there is no contact between the articular surfaces’. Rabbits have very delicate skeletons, and as their muscle mass is large relative to their skeleton injuries to joints can easily be caused through trauma or abnormal or excessive sudden movements. In addition, congenital abnormalities are also seen in rabbits and therefore hip luxation may be commonly encountered in pet rabbits.
Luxation of the hip is when the ball of the hip joint comes out of the socket, instead of normally sitting nicely in contact with each other. This is often caused by trauma, which may be as little as the rabbit jumping and landing awkwardly, or any forceful trauma to the hip, e.g. being trodden on, running into something, fighting, kicking out when being picked up, etc.
Clinical signs after trauma are often immediate with the rabbit having an obvious limp and looking very uncomfortable on the affected limb.
Congenital conditions causing luxation may appear more slowly as the rabbit develops.
Splay leg is a term often used to describe a number of developmental conditions in young rabbits of up to a few months old. 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.
Euthanasia is often the kindest option for those rabbits that have more than one limb affected. Those affected to a lesser degree may be able to cope with careful management of their environment, ensuring they are kept clean and are housed on non-slip flooring.
Since the condition is inherited, affected rabbits should never be bred from.
Diagnosis of luxations can be performed by taking an x-ray of the rabbit’s hips and pelvis. Often two views are needed, a lateral view from the side, and a ventrodorsal view achieved by lying the rabbit on their back.
Rabbits are often sedated or anaesthetised for this, since in order to achieve diagnostic images, the rabbit needs to remain totally immobile.
Sometimes it is possible to put the luxated hip back into its socket by manual manipulation, which must be done under sedation or anaesthesia since it can be painful to the rabbit.
It is sometimes necessary to perform corrective surgery, as often the hip can re-luxate within hours, days or even weeks after being placed back into the socket, and therefore permanent stabilisation is required.