In the latest Pathology Spotlight blog, our Human Remains Conservator, Cat Irving, takes a look at Kyphosis and Pott’s Disease.
The human vertebral column, or spine, naturally forms a series of curves, which facilitate our posture and balance as upright animals. At the neck (the cervical spine) and lower back (the lumbar spine) the curve is inward, or lordotic; while at the upper back (the thoracic spine) and sacrum, the curve is outward, or kyphotic. The terms lordosis and kyphosis are also used to describe postural conditions where these curves become exaggerated or pathological.
Kyphosis usually presents as the upper back appearing more rounded than normal. Sometimes this does not cause problems, but it can present symptoms including back pain, stiffness and tiredness, through to difficulty eating and breathing. Causes can be diverse; kyphosis can develop from poor posture or carrying heavy bags. These can make the muscles and ligaments stretch and become habituated to being in abnormal positions. Conditions such as muscular dystrophy which affect muscle strength can have the same result. It can also be caused by the vertebrae that make up the spine developing abnormally, for example the vertebrae being wedge shaped, or fusing together. Injury can lead to disruption of the normal curves, and conditions like osteoporosis or Paget’s disease can make injury more likely.
The casts and skeletons below, dating to the early nineteenth century, show kyphosis cause by tuberculosis. Most people are aware of tuberculosis as a disease that affects the lungs, but in 15-20% of untreated cases this bacterial infection can affect other parts of the body. Spinal tuberculosis- or Pott’s disease- is seen in less than 1% of all cases of untreated tuberculosis. If the infection invades the two adjacent vertebrae, then the disc that lies between them is unable to receive nutrients and is likely to collapse leading to a sharp increase in the angle of the spine. Here, the collapse has taken place at the disco of the tenth thoracic vertebrae, resulting in the spine forming an angle of approximately 60 degrees. This has caused the chest to be pressed towards the abdomen, creating massive restrictions on breathing and increasing the pressure on the heart. As the vertebrae act as protection for the spinal column running through them, there can be neurological problems below the area of collapse; in extreme cases this can result in paraplegia.
The BCG vaccine is 70-80% effective in its protection against tuberculosis. Treatment for an infection will require a six to nine month programme of antibiotic therapy, though many strains of TB are developing multi-drug resistance, making treatment more difficult. In 2016 the UK had approximately 6,500 cases of TB (according to WHO).