Bone Trauma Lesions
Fractures - Dislocations - Crushing Injuries
Simply put, trauma can be defined as any injury or wound caused by a force or mechanism extrinsic to the body. Traumatic lesions seen in the skeleton can be subdivided into four major categories: Fractures, Dislocations, Crushing Injuries, and bone wounds caused by sharp foreign instruments. For the purpose of this website, bone wounds will be discussed more in depth on the pages involving specific war trauma.
Trauma in archaeological context can help shed light on many factors about the lifestyle of the individuals. This evidence of past populations can tell us more about their culture, economy, environment, occupation, diet and interpersonal violence. These factors are now the focus of Paleopathology.
In the broadest sense, the term ‘fracture’ can be any traumatic event that results in partial or complete discontinuity of bone. This discontinuity can be complete, in which total separation of both ends of the bone occurs, or incomplete, also known as an infraction.
There are 3 major causes of fracture: acute injury (e.g. car accident); underlying disease, termed pathologic, that weakens bone (e.g. Tumor); and repeated stress (e.g. hairline fractures). And each is caused by one of a few types of dynamic forces: tension, compression, torsion, flexion, and shearing, with each causing a different type of fracture pattern.
The result of sudden impaction and causes several different fracture patterns. In long bones it will cause the bone cortex to buckle and bulge. These are most common and best illustrated in the spine, but can also be seen in high impact skull fractures and joint surfaces.
This force is directed in a spiral or twisting fashion. They are frequently seen in skiing and other types of athletic accidents. Often confused with compression fractures in long bones because they tend to follow a natural spiral cleavage plane in the bone.
Also, known as a bending fracture, it is the most common type of bone separation. Usually the result of a fall or in response to a strike, as in the Parry Fracture of the forearm.
In youths, bending fractures are often incomplete and result in a condition known as Green Stick Fracture.
This type of fracture results when opposing forces are applied to bone at different points. One example is Colles’ Fracture.
The second major category of trauma lesions, also known as luxation. The joint components of the joint are completely out of contact and the joint capsule is disrupted. The partial displacement of the joint components are known as subluxations. These pathologies may be congenital or spontaneous; however they are most commonly caused by trauma and associated with a fracture.
Joint capsule damage is a primary complication to dislocations and can result in the ossification of the membrane, ligament, and tendon attachments.
Dislocations tend to be more frequent in adults. The primary reason for this is that in children, the epiphyses have not ossified and will only cause a separation; and in the elderly, the onset of senility or osteoporotic bones will usually result in the fracture of brittle bones.
Dislocations commonly occur in the fingers and toes, especially in association with rheumatoid arthritis. It also can occur in the vertebral column, almost certainly resulting in immediate death. Dislocation of the hip and the shoulder are the most common. The digits and the shoulder can easily be reduced at the time of dislocation making it a rare find in the archaeological context, whereas the dislocation of the hip is very common.
Crushing fractures are very severe and may be caused by falls or blows from heavy objects. They commonly occur in cancellous bone; also seen most frequently in the hands, feet and skull.
Crushing fractures that involve the skull usually become infected and may prevent complete healing of the fracture, leaving a hole in the cranial vault. This is often confused with trephination.
In crushing injuries, the bone collapses on itself. Since this causes such extensive damage, a large callus forms and may produce fusion and deformity of the bones involved. There are 3 types of crush fractures: depression, compression, and pressure.
Depression fractures occur when one side of the bone is crushed and is often seen in skull fractures.
Compression fractures are similar to depression fractures but the crushing force here is applied to both sides of the affected bone.
Pressure fractures are the result of a premature bone reacting to the direct application of force. This is seen in many cultural alterations such as the binding of the feet or skull for beautification.