One of the more common presentations in sick puppies is when they present knuckling over, either while standing or when trying to walk. There are many possible causes of why puppies would knuckle over. Knuckling over is usually a sign of weakness, which is often secondary to metabolic factors and/or neurological factors. For example, puppies with low blood sugar are often quite weak and may knuckle over when attempting to walk. These puppies also may have little appetite, be very weak and may even present with tremors or even seizures.
Treatment of these puppies will center on slowly raising blood sugar, as well as treating the many possible underlying causes of low blood sugar. Puppies with brain and/or spinal lesions also may present with knuckling over. Certainly trauma, toxins, and various viruses all may affect the nervous system resulting in knuckling over. Developmental abnormalities of the spinal vertebrae may lead to spinal compression and secondary knuckling over may be seen. Treatment will be determined by correcting these underlying causes, and prognosis will also vary, as long as these underlying causes are treatable.