STUDIES ON THE SO-CALLED WHIPLASH INJURIES

Report 1<BR>The clinico-statistical observations are made of a large group of patients with the socalled whiplash injuries and their results summarized as follows:<BR>1) The subjects used in this study were a total of 28, 362 patients, seen in our clinic during the past 5 years, of whom 1, 187 (or 4.19%) were of traffic accident.<BR>2) The most frequent site of injury was the cervical region, accounting for 47% of the cases studied.<BR>3) According to our classification, 578 of the entire 611 patients, treated as so-called whiplash injuries during the last 3 years, were found in sprain type of the cervical spine (with associated damage to muscles and ligaments), only a very few in fracture and dislocation types.<BR>4) Recovery from injuries was attained within a month or two in the great majority of the cases, but repuired 6 months or more not infrequently in those of above 40 years presumably because of the injuries superinduced onto preexisting aging processes.<BR>5) Residual complaints and symptoms mostly included heavy head, tender shoulders and tenderness over the trapezius muscle.<BR>6) Therapeutic outcome was definitely more favorable with immobilization in plaster cast than without it.<BR>7) The course of the disease was also investigated and it was considered that those symptoms, worsending after a certain interval, were mainly due to the associated disorder of the soft supporting tissues.<BR>Report 2<BR>The study described in Report 1 showed that the application of immobilization was reasonably effective in recovery from the so-called whiplash injuries. However, the true nature and pathology of the injuries are still obscure and there not infrequently are instances in which symptoms make an appearance not simultaneously with bu behind the trauma.<BR>In the present study an experiment simulant of actual automotive accident was therefore conducted utilizing apparatus devised by the author, in which rabbits were shocked form behind (at an impinging velocity of 20 km/h) and were then examined for their cervical spine roentogenologically as well as for the cervical spinal cord and its surrounding tissues both macroscopically and microscopically. The results thus obtained are summarized as follows:<BR>1) In not a single instance there was any definite X-ray evidence of damage to the bone.<BR>2) Following the experimental injury there were extradural hemorrhage, subarachnoid hemorrhage, swelling of the dura mater, periradicular hemorrhage, extravasation surrounding the vertebral artery, and subarachnoid and extradural edema noted in both of the groups A (without immobilization) and B (with immobilization) .<BR>These change varied in their degree and extent with time, the hemorrhages and edema attaining to their maximum in 24 hours and tending to subside thereafter.<BR>3) At the 2nd day of receiving shock 3 animals exhibeted paresis like symptoms in the left forelegs, which disappeared afterwards. These symptoms were inferred to be due to hemorrhage and edema from the fact that they occurred at the height of the latter manifestations.<BR>4) The predominant macroscopic change just after the injuries was extradural hemorrhage; extravasated blood tended, with the elapse of time, to be centered around the arch of vertebrae, especially intervertebral foramina, and was observable until the 7th days.<BR>The predilecting site of hemorrhage in ventral to the spinal column and appears to be closely related to the presence of congestion of or bleeding from the venous plexus at the posterior edhe of the vertebral body and of damage to the periosteum. It seems that the blood extravasated moves downwards with time through the vertebral canal or foramina to be gradually absorbed.<BR>5) Histological examination showed evidence for the persistence of the extradural, periradicular and periarterial hemorrhage more longer than 7 days in all of the cases studied. Intramedullary hemorrhage was noted in none.