A spinal cord lesion is a traumatic injury to the spine. The consequences depend on the location and severity of the trauma. Fortunately it is a rare injury. It is estimated that the annual incidence of spinal cord injury (sci), not including those who die at the scene of the accident, is approximately 40 cases per million population in the usa or approximately 11,000 new cases each year. Since there have not been any overall incidence studies of sci in the usa since the 1970s it is not known if incidence has changed in recent years. Before the Second World War the prognosis for such people was poor, but thanks to the advance of medical science life expectancy has risen markedly and at present is only slightly a few years below the norm. The number of people in the United States who were alive in December 2003 who have sci has been estimated to be approximately 243,000 persons, with a range of 219,000 to 279,000 persons.
Many people with a spinal cord lesion experience problems in their sex lives. Irrespective of the height of the lesion, experiencing a ‘normal’ orgasm is no longer possible. However a portion of spinal cord lesion patients are able to experience a form of orgasm. Often these are pleasant sensations in the transitional area between presence and absence of sensation. Possibly erratic nerve activity in the brain plays a part in this, since such activity bypasses the spinal cord.
The feeling of an orgasm is sometimes actually unpleasant, although patients turn out to experience a certain relaxation afterwards. The nerves that exit on a level with the spinal segments from the eleventh thoracic vertebra to the second lumbar vertebra (T11-L2) deal with the first part of ejaculation in men. If there is trauma above the tenth thoracic vertebra there is no more transportation of sperm, so that ejaculation is no longer possible. If there is a complete spinal lesion between tii and L2 the results are unpredictable, depending on whether there are still impulses via this level to the epididymides, seminal ducts and seminal glands. In the case of a complete spinal cord lesion between the third lumbar vertebra and the first sacral vertebra (L3 and si), sperm transportation and ejaculation generally remain intact.
In involuntary childlessness the poor quality of the sperm plays a role in addition to erection and ejaculation problems. The causes of this are ‘accumulation’ due to the lack of spontaneous ejaculation, epididymal inflammations and too high a temperature. In wheelchair patients the testicles hang more or less constantly in a warm environment.
There are various methods of treating fertility problems in cases of spinal cord lesion. If manual stimulation does not produce an ejaculation, an ordinary vibrator can be used, and if that doesn’t help, a more powerful vibrator. In 8o per cent of men with a spinal cord lesion an ejaculation can be produced in this way. In individuals with a spinal cord lesion above the sixth thoracic vertebra, though, it may cause raised blood pressure and even cerebral haemorrhaging. For that reason there must be a doctor on hand, at least the first time. A similar expensive vibrator can also be used in the case of anejaculation with different causes, including psychological ones. Both the vibration frequency and the amplitude can be adjusted. The optimum amplitude with spinal cord lesion is 2.8 mm and a frequency of ioo Hertz. If no ejaculation can be produced with this method, the next step is electrostimulation. This involves the giving of electrical impulses via a thick probe in the rectum, causing the release of sperm cells which can subsequently be removed from the bladder. If the quality is good, the sperm cells are frozen and are used at a later date for icsi.
This equipment was developed by vets involved in breeding programmes in zoos. In the 1970s zoos stopped capturing animals straight from the wild. An out-and-out sex and sperm tourist business developed. The sperm was obtained, with the animals under anaesthetic, by electro-ejaculation. If necessary the males went travelling. Coordinated breeding programmes monitor the reproduction of several hundred animal species of virtually all the zoos on earth. The experts look at the sex distribution, age structure and the degree of relatedness of all animals of the same type in the various parks and zoos. In this way a breeding plan is drawn up, laying down what animals may have descendants with what others.
chapter nine