Colin Howie's diagnosis is direct and disturbing.

According to the president of the British Orthopaedic Association, the National Health Service in Scotland is a victim of the disease known as creeping privatisation. Bed shortages, he says, mean patients are increasingly being sent to private hospitals for their operations and that the problem is no longer one of the winter months only. There is not a winter bed crisis, says Mr Howie, there is a bed crisis full stop.

The evidence of the crisis has become clearer in recent weeks. Figures obtained by The Herald earlier this month showed almost 30 patients a day are now having their operations cancelled due to bed or staffing shortages and that the situation is getting worse. The figures showed that in Tayside alone, 88 operations had been put off since the start of the year, which is more than double the number of operations cancelled in the area over the whole of the 2013/14 financial year.

We also know that the pressure on hospitals is no longer confined to the winter months, with the figures for last summer showing that in July and August, 3,309 patients had to be looked after in the wrong department for their condition. Last July, 1,706 patients were also stuck in hospital even though they were well enough to be discharged.

The result of all this strain on the system, says Mr Howie, is that the use of private hospitals is becoming routine and significant for many health boards throughout Scotland. He has no issue with the standard of private care itself, but he says the use of private hospitals means patients are having to go to other areas to be treated and that such a situation is not sustainable or cost-effective. He also believes it is a symptom of a deeper problem with our national health service: the lack of beds when they are needed.

The use of private hospitals is nothing new of course, and, in principle, it should not be a threat to the fundamental principles of the NHS in that patients at no point are being asked to pay for their operations. Whether private hospitals are used or not, the central, cherished idea of the service is that it is, and must forever be, free at the point of delivery and the Scottish Government's re-iteration of its commitment to this principle is welcome.

However, the former health secretary Alex Neil said the use of private care should be a last resort rather than routine, but that is far from the case and the Scottish Government has not kept Mr Neil's promise that it would be a temporary phenomenon. In fact, although the number of private operations is a very small percentage of the total, there is no sign of an end to the practice. Quite the opposite: it continues to be necessary because of the continuing beds crisis in the service - a crisis which is still a long way from being solved.

Until the Scottish Government tackles that crisis, the use of private hospitals is very likely to continue, and the crisis will not be solved until there is a clear strategy based on reliable evidence about where the service is not coping and why. When an operation is cancelled, it is often because the bed is being used by a patient for whom there is no available care in the community and that is caused by a lack of co-ordination between care in the community and care in hospital. Until the Scottish Government fixes that problem, the NHS's reliance on private hospitals is likely to continue.