56.8 Amputating below the knee

This is the most common amputation. If a patient has a good prothesis, he can do almost anything with it. The method described below, that of Perssen, as modified by Anderssen, uses two short equal medial and lateral flaps, and is especially suitable for leprosy and ischaemia. You can use it. for all purposes, except when a guillotine incision would be wiser (56.2).

The best length of stump for a modern prosthesis is 12 to 18 cm below the patient’s tibial tuberosity. If he is to have the traditional type of peg leg he needs a shorter 10 cm stump. A stump of only 5 cm too easily slips out of a prothesis, so that he will be better with an amputation higher up. Don’t amputate below the muscle area of his calf, because the tissue here has a poor blood supply.

Figure 56.13: AMPUTATING BELOW THE KNEE using two equal medial and lateral flaps. This is the most common amputation. If a patient has a good prothesis, he can do almost anything with it. After Perssen and Anderssen.