Transtibial amputation (below-knee amputation) is a surgical procedure performed to remove the lower limb below the knee when that limb has been severely damaged or is diseased. Trauma can also be the cause for amputation. Most transtibial amputations (60%–70%) are due to peripheral vascular disease, or circulatory issues. Poor circulation limits the healing and immune responses to injury; foot or leg ulcers may form as a result which may not heal and develop an infection that can spread to the bone and become life-threatening. Amputation is then performed to remove the diseased tissue and prevent the further spread of infection.
The surgery is usually performed by a vascular or an orthopaedic surgeon. The diseased or severely injured part of the limb is removed, keeping as much of the healthy limb as possible. The surgeon shapes the remaining limb to allow the best use of a prosthetic leg after recovery. Care is taken by the Surgeon to ensure that the residual limb is not too long or short for prosthetic components to fit. In planned surgeries, the Surgeon may consult a prosthetist for optimum residual limb length.
A below knee prosthesis usually easier to use than an amputation at a higher level. The higher the level of the amputation the more energy is required to ambulate. Depending on the individual’s physical condition, with training on the prosthesis, independence from assistive devices such as crutches can be achieved after 4 to 12 weeks from the date of receiving the prosthesis.
With a below knee prosthesis the client would be able to do most things they did prior to amputation depending on their physical condition and the condition of their residual limb. They would be able to stand, walk and sit comfortably. They would also be able to negotiate ramps and stairs, ascending and descending foot over foot without much difficulty as well as walking on uneven terrain. Walking for longer distances without any issues or assistive devices can also be easily achieved. Some components can also be used in water. Please let the prosthetist know if using a prosthesis in water is an important factor to consider.
A Transtibial socket is custom made according to the shape and size of the residual limb and is the most important part of the prosthesis as it interacts with the residual limb to ensure comfort and function.
The prosthesis is suspended by various methods that would be discussed during the assessment consultation. The main suspension methods are suction or pin lock, both with a silicone liner. Weight bearing is distributed over the entire surface of the residual limb with contact but no weight bearing on the bottom of the residual limb.
A variety of feet with varying properties can be used with this type of prosthesis and this will be selected by you and your prosthetist.
Some patients prefer their prosthetic components exposed with the pylon and adaptors showing, others prefer the prosthesis to look more life-like while some want it to make a statement and stand out. We can provide for all these options. It is important to let the prosthetist know if the look of the prosthesis is important so that this design aspect is addressed.