Melissa Kaplan's
Herp Care Collection
Last updated January 1, 2014

Dry Gangrene of Tail and Toe

©1996, 2002 Melissa Kaplan

Tail
Injuries near the end of the tail often result in dry gangrene. The tail may have been crushed or caught in something, such as in a closing door or between the shelf and the wall of the basking area.

The tissue, starting at the end of the tail, begins to die, turning dark brown or black, becoming very hard and brittle, shrinking inwards, collapsing in on itself. The bony processes of the tail vertebrae are easily visualized as they create ridges under the skin of the tail.

Sometimes the crush injury or severe infection may occur towards the middle of the length of the tail. As the infection progresses, the tail feels mushy in that area. As the blood and nerve supply are disrupted in this area, the mushy area spreads down towards the tip and up towards the body. The tip may take a long time to start showing signs of dry gangrene, but the tail should be dealt with, usually by amputation, long before it gets to the point of dying and becoming brittle.

The dead, brittle section may be knocked off when the iguana whips its tail against something. Waiting for detachment to happen on its own, however is not a good idea.. If not amputated, it may continue to spread farther up the tail. This may happen rapidly, in a matter of days or weeks, or slowly, over the course of several months.

Treatment
When caught in time while it is still near the end of the tail, the amputation is very quickly done. There is very little bleeding and stitches are rarely required. Amputations done in the fleshier parts of the tail may have the skin stitched over the stump and the iguana started on systemic antibiotics. This will help reduce infection. It will not interfere with tail regeneration. Needless to say, amputations are best done by a reptile vet under sterile conditions!

The tail must be severed in the healthy tissue. If the cut is made in the dead tissue or close to the demarcation between healthy and dead tissue, too often there is enough bacteria left in the end of the stump to continue the gangrenous process. This results in more of the tail dying and further amputations. While it is always sad when an iguana loses any part of its glorious tail, it is better to chop off what needs to be chopped off at one time, rather than subjecting the iguana to further infection and the stress of repeated surgeries.

Dead Toes
Toes may also be injured due to crush or twist trauma severely enough that the tissue dies. The toe may remain viable looking, green and filled out, but may flop around uncontrollably with the iguana moves. At other times, the toe may start looking as described above for the tail, turning black and collapsing down, becoming brittle or hard.

These toes, too, should be amputated. This will prevent the spread of any infection and will eliminate the risk of the toe being caught in something and literally being ripped off. Iguanas do very will minus a few toes, and often times removing a source of infection will speed overall recovery.

Retained Shed and Carpet Threads
Another common reason cited for the loss of toes through tissue death and autoamputation is that free roaming iguanas get carpet fibers wrapped around their toes. The inelastic fibers fail to stretch as the toe grows, engirdling it, and eventually the blood and nerve supply are cut off, with that part of the toe farthest away from the body dying.

What many people fail to realize is that it is more common for retained shed on the toes and tail to cause a similar engirdlement and tissue death. Human hair may cause similar problems, especially with older and larger iguanas whose scales on the bottoms of their toes become quite rough and flared.

Prevention
Checking the toes and tail frequently, after bathing the iguana and when trimming the claw tips every two weeks, will ensure that nothing gets trapped around the toes or tail long enough to cause any damage to the iguana.

Don't Let Things Get Out Of Control
One of the biggest problems with "cheap" reptiles is that people get them who can't afford to pay for what the reptiles need, including veterinary care. As more reptiles are being dumped on people willing to take them in, we are now seeing rescuers who are overwhelmed by the sheer numbers of animals coming in and by the expense of providing for them. The sad fact is that it is always the animals who suffer, despite the intentions of the humans. Pugsley, the now tail-less iguana, illustrates both situations: owners who didn't care for him properly, and an initial rescuer who couldn't afford to get his necrotic tail taken care of.

There's an old joke about yachts: if you have to ask how much they cost, you can't afford one. Pets are the same: if you have to wonder and worry about how much it might cost, then it is not the right time for you to have one. If you cannot afford the proper care, including veterinary care, for your pet, find someone who is qualified to care for them properly before a major problem develops. If a problem gets out of hand and you can't find anyone to take the pet and you can't borrow the money needed to get the necessary treatment and care, then talk to your vet about humanely euthanizing the pet. In the long run, it is far kinder than letting it linger, in pain, until it finally dies.

Per Scott J. Stahl, DVM, Dip ABVP
San Diego County VMA Conference Proceedings, September 1999

"Trauma to lizards' tails may result in vascular compromise and necrosis. Bacterial and fungal infections (often resulting from invasion of opportunistic organisms after some initial trauma) may also lead to necrosis. Amputation of a portion of the tail is often the most effective treatment. It is important to know the species of lizard that you are performing the surgery on as some lizards will regenerate their tails and others will not. Lizards that will regenerate their tails (iguanas, geckos, and some skinks) should not have their tails sutured as this will impede tail regeneration. Also, the amount of tail that must be amputated and/or the site of the amputation is also a factor in management. For example, if the lizard is mature and the amputation is very proximal it may be necessary to suture the skin. The tail should be examined closely to discern where the healthy tissue ends. The tail amputation site should be a safe distance proximal to the line where the healthy tissue stops." (From Capsule)

Melissa Kaplan notes: I've never seen stitches impair a green iguana's regeneration. Rather, age and size, and possibly social status if the iguana is a member of a group of iguanas, seem to be the determining factors.