A dislocated ankle is complicated in a dog

SPARKY took a tumble when out running on a walk: his foot had slipped into a hole in the ground. He was badly injured, with a dislocation of his ankle joint, so that his foot was pointing at right angles compared to the rest of his leg. His foot was flopping around uselessly, and he was in pain. His owner rushed him into my clinic for urgent treatment. The first stage of the treatment process was to carry out a complete analysis of his injury. We gave him a general anaesthetic to remove his pain, and we took a series of x-rays of his lower limb. The ankle joint is a complex structure, with many small cube-shaped bones, neatly slotted together like a complicated Chinese puzzle. When x-rays are taken, the multiple tiny bones are superimposed on each other. It can be difficult to identify the individual bones, and multiple views, taken from different angles, are needed to obtain a full analysis of the joint. In Sparky's case, the x-rays revealed good news: there were no broken bones. The joint between his shin bone and his ankle bone had been completely dislocated, like a door being lifted off its hinges. Under the anaesthetic, I was able to slot his ankle joint back into its normal position, but as soon as I let go of the bones, they flopped back into the dislocated position. There was no bone damage, but all of the supportive ligaments around the joint had been torn. There were two treatment options for Sparky. Ideally, according to modern veterinary science, he needed to have radical surgery on his ankle joint. Steel pins would be inserted into the bone above and below the joint, and strong wire would be used to link the pins together. In this way, an artificial ligament would be created, and the ankle joint would be held firmly in its correct position. However the time-consuming, intricate surgery would be very expensive. The second treatment option was much simpler. We could place his damaged leg in a supportive cast for a month, and hope that nature would provide a cure. With luck, scar tissue would form around the damaged joint, and this might be enough to keep the ankle stable enough for normal daily life. However there was a high risk that this low-input approach would fail, and surgery would still be needed. When I explained the situation to Sparky's owner on the telephone, he asked me to try the simple supportive cast first. I stressed that the approach might not be successful. It was quite likely that we would remove the cast after a month, only to find that his ankle was as badly dislocated as ever. Sparky's treatment went well at first. He did not mind having a cast on his leg, and he left it alone, without chewing it. He kept it clean and dry. He came back once a week to have his cast checked. Everything was going well. I had planned to leave the cast on for a full month, but after three weeks, his owner phoned. Sparky had managed to chew his cast off. I feared for the worst, so when he arrived for his check up, I was delighted to see him walking normally across the car park to our hospital door. I felt his joint carefully. His ankle had stayed in its correct position, and scar tissue had replaced his ligaments successfully. On this occasion, good luck and the natural healing ability of a healthy young dog had been on our side.