Amputation of the Lower Limb

The amputation of a leg is a major happening for a person and represents an upheaval in their life, with psychological problems added to the difficulties of learning the rehabilitation, the management of the new prosthesis, and the relearning of ambulation. The surgeon’s plan will be to manage the process to allow the patient early access to rehabilitation, reduce their energy requirements in walking to the minimum and allow them to manage the prosthesis successfully. Many new skills have to be learnt such as mobilising without the new limb, checking the skin pressure areas and managing to get the limb on and off.

To manage all these skills and learn how to be as independent as possible the patients need a skilled team to manage them which includes their own doctor, the surgeon, a physiotherapist, an occupational therapist a prosthetist and perhaps an employment adviser. The number of lower limb amputations is likely to continue to rise as the elderly populations increase in more advanced industrialised countries, with ischaemic vessel disease the primary cause. The proportion of above knee to below knee amputations has changed as surgeons became more skilled at preserving the knee joint so that the present ratio is 30% above knee to 70% below knee.

Peripheral vascular disease (PVD) is the most common reason for amputation with a significant number of patients suffering an amputation on the other side within three years. Most patients are elderly and have ischaemic problems which are secondary to diabetes, with peripheral neuropathy a common difficulty which can lead to ulcers and gangrenous changes. Trauma to the lower limb which involves the arteries and nerves can be treated but may result in a leg which is painful and does not function well, meaning that an amputation would be preferable for speedy rehabilitation and return to normality.

Amputation is also employed for less common conditions such as infections, congenital lower leg abnormalities and tumours. The planning for an amputation should be viewed as an operation targeted at reconstruction and not just removing a body part, aiming for the planned independence and function of the patient. As the level of the amputation progresses up the leg this increases the work of walking, requiring increased levels of oxygen concentration, increased expenditure of energy levels and reducing the speed the person is able to walk. Below knee amputation shows little increase in energy needed for walking but mid thigh can increase this by fifty percent.

The energy load of walking may be very important as many patients who undergo amputation suffer from peripheral vascular disease and may have other medical disorders, all meaning that much of their reduced energy may be consumed in walking. This means that getting sufficient strength and walking ability to attain functional independence may be difficult. Healing after amputation is not a foregone conclusion due to the likely reason for the operation being poor circulation, and the condition of the skin exerts an important influence over the overall functional outcome for the patient. The soft tissues around the amputation site function as the connection between the prosthesis and the leg.

The amputation stump region must be large enough and the tissues be of good enough quality to allow effective gait by transmitting the lengthways and shearing forces which will be transmitted through it from the socket of the new leg. Direct weight bearing on the end of the stump can occur in amputations which are performed through a joint such as the knee and the ankle, but this style of amputation has its difficulties. The new knee joint is inevitably formed below the level of the old one, causing the knee to stick out obviously further than a normal knee and the calf to be correspondingly shorter.

PVD or peripheral vascular disease is the most prevalent reason for amputation, with elderly patients being the largest group and often having a second amputation inside three years. Ischaemia of the tissues occurs, often the result of diabetes which can then progress to neuropathy of the peripheral nerves, ulcers and eventually gangrenous changes in the limb. An accident to the leg involving open fractures and arterial and nerve damage can now be medically managed to save the leg but this may not always be positive as an amputation could permit early progress via rehabilitation towards independence.

Jonathan Blood Smyth is the Superintendent of Physiotherapists at an NHS hospital in the South-West of the UK. He writes articles about back pain, neck pain, and injury management. If you are looking for physiotherapists in bradford visit his website.