Amputation of the Leg
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.
Weight transfer can be achieved indirectly by allowing pressure through a bony point higher up the leg and also by effecting force transfer through the sides of the leg tissues. There may often be a pain issue after this procedure despite modern prosthetic accomplishments and if the pain is significant it can lead to limited use of the prosthesis, functional reduction and eventually to further attempts at surgery.
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 requirements for gait are extremely important as amputated patients frequently suffer from ischaemic tissue problems or other medical conditions which lead to walking consuming much of their energy abilities. Independence in functional activities may be hard to achieve as much of their limited energy supplies is taken up with simply walking. After the amputation, due to the skin viability and ischaemic diagnosis, healing may be delayed and this can have an important bearing on the eventual outcome for the patient’s independence. The soft tissues at the site of amputation must act as the connecting point between the leg and the prosthesis.
Allowing a bony area higher up to take some of the weight transfer indirectly can be successfully integrated with weight transfer sideways through the soft tissues of the lower leg. There may still be pain issues for patients despite the many advances made in modern prosthetics. Significant pain can lead to a reduction in function, reduced use of the prosthesis and even to further surgery.
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, editor of the Physiotherapy Site, writes articles about physiotherapy, physiotherapy, physiotherapist in northampton, back pain, orthopaedic conditions, neck pain and injury management. Jonathan is a superintendant physiotherapist at an NHS hospital in the South-West of the UK.
