Deviations or lumps in the spine can be due to congenital defects or malformed vertebrae. They are also seen in cases of severe malnutrition and as a result of trauma. Bone infection or osteomyelitis can occur where a bone has been broken or otherwise damaged, perhaps by a fall or other blunt trauma. In the case of a snake, the spine or ribs may be affected.
Other metabolic and possibly viral conditions exist in snakes which can cause spinal deformity. This includes Osteitis Deformans, a disease much like Paget's disease, seen in humans. Bone swellings can be detected in the ribs or more likely along the spine. There may be a single area of firm swelling, or an area of spinal deviation, either a sideways "kink" or a protruding lump. The area might be painful to the snake, and he might be reluctant to move or have difficulty moving. An examination by your reptile veterinarian, the snake's history and radiographs (X-rays) are the first steps in determining the nature of a bone swelling. Further tests might be relevant and are discussed below.
Internal Lumps or Swellings
It is common to feel the prey within the digestive tract, particularly in lean, fit, recently fed snakes. The snake's stomach is located approximately midway between the head and the vent. After this point, the prey is sufficiently digested that it should not be easily felt. That said, it is recommended that snakes not be handled for at least 48 hours after they have fed, to minimize the risk of regurgitation.
Swellings or lumps associated with the gastrointestinal tract can be abnormal. Undigested prey can cause a swelling in the stomach (mid-body) region of a snake whose housing conditions (particularly temperature) are not adequate. Food may be physically prevented from passing through the digestive tract by an obstruction. Such obstructions can be created by parasites, foreign bodies, previously undigested meals, tumors, abscesses, granulomas (bacterial or fungal masses), force feeding or the feeding of too large a meal.
Viral, bacterial, fungal and parasitic conditions can thicken the lining of the digestive tract and affect its ability to digest and propel food, causing a functional, if not physical obstruction. Snakes suffering from serious or systemic disease such as kidney or liver failure may not have normal intestinal motility. Snakes kept in conditions which are not warm enough will be unable to move food through the gastrointestinal tract at a normal pace.
Ingested material can become lodged at any point along the digestive tract. Snakes whose prey is too dry, who do not have access to water or whose environment is insufficiently humid may suffer from chronic dehydration and will easily become constipated. It is possible to see snakes who have not had a bowel movement in some time and have several fecal masses palpable in the colon. Lumps adjacent to the digestive tract can put pressure on intestinal contents, preventing their passage.
Female snakes in breeding condition may have large developing follicles on the ovaries. These can be palpated by experienced people, but this is not recommended in most cases as follicles are extremely delicate and can burst with handling of the snake. Although the young of live-bearing or viviparous snakes may be detected as a swelling in the last half of the body, the eggs of an oviparous snake are more easily felt and recognized for what they are.
Swelling associated with the reproductive tract may also be abnormal, associated with egg binding, retained fetuses, tumors or infection.
Enlarged livers, kidneys and other internal organs may be palpated with skill. These may reflect infection, cancer, cysts, degenerative or metabolic disease.
Obesity is a common problem among captive snakes. In addition to other health risks, obese snakes are difficult to palpate, as the organs are surrounded by fat. These fat deposits can become lumpy and in some cases inflamed, particularly in the case of snakes fed obese prey. Palpation alone will not differentiate between fat and a more sinister lump.
Virtually all the internal organs can be affected by disease, some more commonly than others. Internal abscesses, granulomas and cysts are seen in snakes and if large enough will be detected directly by owners or veterinarians. Entire organs or tissues may also enlarge enough to be physically detected as an internal mass. Enlargement may be due to bacterial, viral or metabolic conditions. Tumors or cancer are also not unusual in snakes. These have been recognized in the skin, muscles, liver, kidney, reproductive tract, bone and eye, among many other sites.