Low Speed Collisions Resulting in Injury?

Defense experts commonly opine that forces encountered in low speed collisions are insufficient to cause serious injury.

PDMG Consulting response:

On the contrary, there is ample evidence in medical practice, backed by credible literature that indicates that collisions at low speeds as low as 10 km/h can do much harm to the human body.

One such example involves the cause of thoracic outlet syndrome (TOS). Medical literature notes TOS to be a combination of neck and or shoulder trauma plus an anatomic predisposition.

Neck or shoulder trauma, caused for example in auto crashes, as a causative factor of TOS resulted from observations reported by a few thousand patients whose symptoms of pain in their necks and arms, as well as numbness in their hands, developed soon after a motor vehicle crash. This observation was followed by studies that demonstrated significant cell changes in the neck and back muscles of patients with TOS.

Congenital bands and ligaments are observed in a large majority of TOS patients. Several different kinds of bands have been recognized and categorized. These bands and ligaments are present at birth. In patients with TOS, they become associated with symptoms following trauma – even minor trauma. The anatomic findings are, therefore, usually regarded as a pre-disposing factor and not the causative agent.

One would assume that if the site of pathology in TOS is the scalene muscles. There should be abnormalities found in them. In fact, findings of muscle scarring have been found and reported in the medical literature.

Based on the above observations, namely a history of neck or shoulder trauma with variations in normal anatomy and cell changes in scalene muscles, one can readily explain the pathophysiology of TOS. The underlying pathology in most patients is scarring of the scalene muscles caused by shoulder or neck injuries. The tight scalene muscles (due to scarring) cause neck pain and headaches, as well as temporomandibular joint (TMJ) symptoms, which usually develop within a few days of the crash. As scarring in the muscles develops, the muscles compress the brachial plexus (a network of nerves, running from the spine through the neck, through the armpit region and into the arm). The compression elicits the symptoms of pain, numbness, and weakness of the upper extremity.

The onset of extremity symptoms may be delayed a few days to weeks, and in some patients, even months – as it takes time for scar tissue to develop and compress. As the pathophysiology becomes established, scarring adds to the problem. These injuries set up a vicious cycle. Pain, bad posture, poor physical conditioning and anxiety then aggravate that cycle.

In conclusion, the anatomic problems that lead to TOS are now well-known and documented in the medical literature. They consist of congenital anomalies that are superimposed on some fort form of trauma – even trauma caused by low impact forces.

Used with permission from MD Business Consultants.