Breaks without bruises : Are common and can’t be said to rule out non-accidental injury (2024)

Everyone knows what constitutes a bruise, and most people understand what a fracture is. The Shorter Oxford English Dictionary defines a bruise as “a breaking, a breach, an injury to the body causing discolouration but not laceration,” and Stedman’s Medical Dictionary simply describes a fracture as “a break.” As both bruises and fractures are concerned with breaks, it would be logical to assume that they invariably occur together. Colloquially, orthopaedic surgeons describe a fracture as “a soft tissue injury complicated by a break in the bone.” However, the reason this definition arose was because, all too often, the intimate link between the bone and its soft tissue surrounds was forgotten as the soft tissue injury, while undoubtedly present, was not visible to the naked eye. Bruising is thus a variable feature which can be out of all proportion to the perceived injury and the pain associated with it. The general public understands this dilemma: how often has a relatively trivial knock resulted in an impressive bruise and much sympathy when, in contrast, a more forceful blow has left you with nothing to show for your pain and suffering?

When a bone breaks bruising may result either directly from the force which caused the injury or from the fracture itself and the consequent local soft tissue haemorrhage. So, if a direct force such as a kick to the shin results in a fractured tibia bruising secondary to both the kick and the fracture may occur, and both bruises will be at the same site. With an indirect force, such as the twisting that may be applied to a leg during a fall, the bone breaks at a distance from where the force was applied. In such cases there are two sites of potential bruising. The indirect force itself may be relatively minor and therefore no bruising is seen at the site where it was applied. Similarly, with an indirect force soft tissue injury at the site of the fracture may be minimal and bruising here may also be absent. This is particularly so if the fracture occurs, as for example in the femur, deep within the soft tissue envelope of the thigh, when the haemorrhage must rise through several fascial planes before it is visible through the intact skin.¹

It is common knowledge among orthopaedic surgeons that there may be no external signs of bruising in association with a fracture, and this is one of the many reasons why so much emphasis is placed on marking the limb before surgery. Unfortunately, though it is common knowledge, it is also unwritten knowledge and perhaps not so well understood by our non-orthopaedic colleagues. Many doctors are now involved in the care of children with fractures, particularly in cases where child abuse is suspected. Some have assumed that the lack of bruising means that a pathological process such as osteogenesis imperfecta is present and that the bone has fractured easily without the use of undue force and therefore is not a non-accidental injury. The work on which these ideas are based has tended to appear in the letters section rather than the peer reviewed sections of medical journals.^2–4 In suspected child abuse, however, the fact that breaks and bruises do not always occur together can have more serious consequences.

Much has been written about the size, shape, and site of bruises caused by non-accidental injury to the soft tissues of a child,⁵ but little has appeared in either the adult or paediatric literature about the presence or absence of bruising in association with fractures. The paper by Mathew et al in this week’s issue starts to evaluate the meaning of bruising in association with fractures in children by suggesting that a high proportion of “normal” fractures in children show no bruising (p 1117).⁶ I hope that this will stimulate further work on the subject and allow us to be more precise over which injuries should cause concern.

Notes

Papers p 1117

References