Are defense experts right when they say that forces encountered in low speed collisions are insufficient to cause serious injury?
Our answer:
On the contrary, there is ample evidence in medical practice, backed by credible literature that indicates collisions at speeds as low as 10 km/hr 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 or shoulder trauma plus an anatomic predisposition.
Neck or shoulder trauma (like auto accidents) 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 since birth. In patients with TOS, they become associated with symptoms following trauma – even minor trauma. The anatomic findings are, therefore, usually regarded as a predisposing factor and not a causative agent.
One would assume that if the site of pathology in TOS is the scalene (tiny muscles in the neck) 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, 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 cause neck pain and headaches, as well as TMJ symptoms, which usually develop within a few days of the crash. As scarring in the muscles develops, the muscles compress the brachial plexus, eliciting 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 form of trauma – even trauma caused by low impact forces.