The spinal cord is a soft tube-like structure that connects the brain to the nerves in all parts of the body. The spinal cord lies in the spinal canal which is a space present in the middle of the vertebral bodies or vertebrae. The vertebrae together form the spine and can be divided into cervical (neck), thoracic (chest), lumbar (abdomen) and sacral areas. The spinal cord present in these vertebrae is also called by the same name such as cervical cord, thoracic cord etc.
The function of the spinal cord is to transmit nerve impulses from parts of the body to the brain and also from the brain to other parts of the body. For example, if we decide to walk, the message is relayed from the brain to the muscles in the arms and legs that will enable us to get up and start walking. Likewise, sensations such as touch, pain, temperature are also felt when these senses are transmitted to the brain.
Spinal cord compression is a condition or a complication that can occur in patients with cancer that has spread to the vertebrae. When there is cancer in the vertebrae, the vertebrae can become weak and can fracture or break or become unstable leading to narrowing of the spinal canal and causing compression or tightening of the spinal cord. This in turn leads to improper functioning of the spinal cord and can cause symptoms in the patient. In some patients, there may not be a break in the vertebrae, but the cancer can grow into the spinal canal and cause compression. It is important to note that not all people with cancer in the vertebrae go on to develop spinal cord compression but can occur in some patients. Cancers commonly associated with this condition include lung, prostate, breast, myeloma and kidney cancers.
The following symptoms should raise the suspicion of spinal cord compression in a patient with cancer, particularly those that are known to have metastases in the bones. Common symptoms are listed below.
Back pain is a common symptom in patients with bone metastases. The pain can be in any part of the spine and when present with other symptoms listed below should alert the patient about cord compression.
Weakness in arms or legs
Weakness in arms or legs can be a sign of impending or established spinal cord compression. Patients who notice sudden or gradual onset of weakness of arms or legs should see a doctor to exclude spinal cord compression. The weakness can manifest in the form of difficulty walking or being unsteady on feet while walking or difficulty to get out of bed or chair when trying to mobilise.
Symptoms such as numbness in the feet, hands or arms or any part of the body along with tingling or altered sensation in these areas could also be a symptom of this condition.
Sudden or gradual onset of being unable to pass urine can be a symptom of spinal cord compression.
Severe constipation or being unable to pass a motion can be a symptom of spinal cord compression, particularly if it is associated with other symptoms mentioned above.
If a spinal cord compression is suspected by a doctor based on the symptoms of the patient and examination, an urgent MRI scan is done to confirm or refute the diagnosis. Once this condition is suspected, it is very important for urgent investigations and treatment to be done as this could improve symptoms and prevent permanent disability.
MRI Whole Spine
An MRI scan of the whole spine is the best test that will determine the presence of spinal cord compression. If an MRI scan is not available or the patient is not suitable for one, a CT scan is the next best test to diagnose this condition.
Spinal cord compression is a medical emergency and should be treated urgently, ideally on the same day of diagnosis and usually within 24 hours.
This is to prevent permanent damage to the cord after which recovery may be minimal. There are two main forms of treatment of this condition. These are surgery and radiotherapy. One or both options may be used depending on the situation and the stage of the cancer and the fitness of the patient.
Steroids are an important treatment option in the management of spinal cord compression. They should normally be started as soon as this condition is suspected even before tests such as MRI etc. Steroids reduce the swelling around the cord and ease the pressure around it. Commonly used steroid in this condition is dexamethasone.
Surgery for spinal cord compression involves decompression of the spinal cord from the cancer around it. This relieves the pressure on the cord and enables it to function normally again. Surgical decompression may include removal of a part of the vertebra along with stabilisation of the spine in situations where it is unstable. The cancer around the spinal cord is also removed. Surgery is commonly done in younger, fitter and in patients with limited amount of cancer in the body.
Radiotherapy is a common form of treatment to manage spinal cord compression. The aim of this treatment is to control the cancer that is causing the cord compression. Radiotherapy can be given in two different ways.
Standard radiotherapy, where the treatment is given over 1, 5 or 10 days is commonly used to treat the condition. This is given once a day and lasts about 5-10 minutes each day.
Patients who have spinal cord compression due to cancers such as lymphomas, germ cell tumours or small cell carcinoma of the lung can be treated with chemotherapy rather than surgery or radiotherapy. This is because, these cancers respond quickly with chemotherapy as compared to others.
Rehabilitation and Physiotherapy
This forms an important part of treatment of this condition and helps the patient to improve their function once all the treatment is completed. Recovery of symptoms related to spinal cord compression can take time and a good rehabilitation programme will help in that recovery process.