WHIPLASH INJURIES By Prof RP Grabe, Department of Orthopaedics, University of Pretoria

Transcription

1 1 WHIPLASH INJURIES By Prof RP Grabe, Department of Orthopaedics, University of Pretoria In a recent publication in Spine the Quebec task force mentions that very little is available in the literature on research pertaining to this very common injury. AS REGARDS PREVENTION: Safety belts should always be worn and suggestions that seat belts may increase the incidence of neck injuries should be ignored. Properly fitted headrests and not neckrests reduce the severity of whiplash associated disorders drastically. THE DIAGNOSIS IS MADE ON CLINICAL GROUNDS: There is no evidence that pressurized diagnostic testing or imaging is needed on a routine basis for the ordinary neck injury, without having critical neurological signs. A careful and detailed history should be taken including the exact mechanism of the injury in order to get some idea of the forces involved, damage to vehicles involved, direction of impact, whether a seat belt was worn and whether a properly fitted headrest was present. It should be known exactly when symptoms started, the exact location of pain, the degree of pain, and whether it is aggravated by specific movements of the neck. The presence of disturbances of vision, hearing and balance, dizziness, headache, unconsciousness, of any referred symptoms down the upper extremities such as pain, weakness, pins and needles are important. The presence or not of previous neck problems should be known and a general medical history should be taken. At this point it is well to remember that all patients with a head injury or a facial injury need to have a clinical and radiological examination of the neck.

2 2 PHYSICAL EXAMINATION: Look at the posture of the head and neck, and any bruises on the forehead and face. Palpation includes the posterior mid-cervical region form the skull down to the upper thorasic vertebrae for tenderness of the spinous processes and or inter spinous ligaments, and tenderness of the posterior muscles of the neck and shoulder girdle. The only way to know whether the anterior structures of the neck have been injured is to examine the anterior longitudinal ligament with the patient lying on her back, relaxed, palpating the anterior aspect of the vertebral column from C3 downwards to T1 on both sides of the trachea. This is an important part of the examination. A detailed neurological examination should be done. It is not recommended that the patient s neck should be subjected to movements at this stage because it is not known whether there is instability of the cervical spine or not. The patient should be examined for possible other injuries. X-RAYS: X-rays include an antero posterior, lateral and open-mouth view with all seven cervical vertebrae and the C1-T1 level included. If the C7 T1 level is difficult to see, such as is the case in heavy muscular patients, either a swimmers view or a tomograms of the spine should be done. No patient should ever be aloud to leave the hospital without having had a proper C7-T1 examination. It is a well known fact that patients with a bifacet subluxation or dislocation can come in to your consulting room walking, send home and collapse, plegic, due to a missed facet dislocation. The soft tissue shadow in front of the cervical spine should not exceed 3mm down to the fifth cervical vertebrae and from here downwards should not exceed 1cm. Especially a fusiform swelling is suspicious of an underlying injury. The distance between C1 and the anterior aspect of the dens should not exceed 3mm. The distance between the posterior aspect of the dens and the posterior arc of C1 should not be less than 14mm. The anterior aspect of all cervical vertebrae should be in a straight line which is slightly convex.

3 3 The same applies to the posterior aspects of the cervical vertebrae including T1. The disc spaces should be parallel ad there should not be more than 11 of tilting of one vertebra on another. The posterior articulations of the facet joints should fit nicely one on top of the other similar to roof tiles. The spinous processes should converge to a central point somewhere behind the neck. The spino lamellar line presents a line formed by the junction of the spinous processes and the laminae of each cervical vertebra and should form a convex line of which the continuity is not broken. On the antero posterior view the spinous processes should be in a straight line and the distance between these spinous processes should more or less be the same. The lateral masses should be screened for possible fractures. On the open mouth view the dens should be situated perfectly in the middle of the lateral masses. In addition there should be no overlap of the lateral masses of C1 on C2. If nothing abnormal is detected on the above mentioned three x-ray views the patient suffers from a soft tissue injury of the neck and the possibility of instability is assessed on the fourth day after admission. A patient suffering from a whiplash injury can present with many different types of fractures and or dislocations. The aim of this paper is only to discuss soft tissue injuries of the spine and not the whole range of fracture dislocations of the neck. On approximately the 4 th day post injury flexion and extension lateral views are taken in the presence of a doctor. Should instability be detected on the fourth day after admission with no positive neurological signs a simple posterior one level fusion should be done. It is important to know that a torn interspinous ligament in the neck can never be relied on to heel with maintenance of stability. This injury always needs a fusion. Let me now give you the Pretoria regime of handling soft tissue injuries of the neck. Unless patients have very minor symptoms and very few positive clinical signs all are admitted and put in 2½kg of traction. Heavy medication is given for approximately 3 days in order to get rid of all muscle

4 4 spasm. The patient is reassessed on the fourth day and, accompanied by a doctor, flexion and extension lateral views are taken. The views are of the utmost importance to rule out instability which can have serious consequences if not picked up. Due to pain and muscle spasm flexion extension x-rays are of no use on day 1. The moment one knows that the spine is stable, the patient can be discharged with a soft collar. At this stage your patient can be reassured and can be kept on a muscle relaxant for another week, given an antiinflammatory drug and one of many pain killing tablets. Patients can go back to work approximately one week after discharge. At this stage the patient should be encouraged to mobilize his neck and to strengthen his cervical muscles. This should be accompanied by good postural guidance including to avoid having the neck in one fixed position such as typing, reading, studying etc. for long periods. The neutral position is recommended as far as possible and in the case of adult scholars we prescribe an oblique platform for use on the patient s desk. PROGNOSIS: Several excellent studies are available in the literature some with a follow-up to 10 years. For the sake of the registrars and those of you doing medico legal work, here are the references of some of them: Donald Gore (Spine Vol 12 nr 1 p. 1, 1987) SP Hodgson (Neuro Orthopaedics Vol. 7 Nr. 2 p. 288, 1989) GJ Vlok (S.A. Bone and Joint Surgery Vol. 3 nr. 2, p.5, May 1993) Macnab (JBJS Vol. 46 A Nr. 8, p. 1797, Dec. 1964) OCNA (Vol. 2 nr. 2 July 1971, p. 389) Gore (Spine, Vol 11 Nr. 6, 1986 p. 521) Evans R W (Neurologic Clinics, Vol 10 nr 4, p. 975, 1992) Quebec Task Force (Spine Vol 20 nr 85, p. 355, 1955) John Chester (Spine Vol 16. Nr 7, p.716, 1991) Gorgan MF (JBJS p. 899, 1990) Mayson Hohl (JBJS 56A nr 8p.1675, Dec 1974) Johnson H et al (Spine Vol 19 nr 24, p. 2733, 15 Dec (Sweden)).

5 5 Surgery for chronic symptoms after whiplash injury, 20 cases. Author: Alger G et al (Sweden) Acta Orthopaedica Scandinavica Vol 64 nr 6, p.654, Dec The injured structures include muscles, ligaments and discs. In several follow-up studies, some for 10 years, it has been found that 30% of patients suffer from permanent symptoms. Bad prognostic signs include: Pain immediately after the injury. Root symptoms. Anterior soft tissue swelling. Divergence of spinous processes. Instability. Hyper extension injuries have the worst prognosis (true whiplash). Blurring of vision (Horner). Dysphagia. Mechanism. Faulty inner ear function should be looked for, it does occur, and involves the semicircular canals. I repeat it is very important, as regards follow up and long term prognosis, that according to most articles ±30% of patients suffer from permanent symptoms. In a study by Gorgan with a follow-up of 11 years he raised the point that an assessment after 1 year differs very little from an assessment after 8 years. Medico legally this is an important observation. Looking at the role of surgery in patients suffering from chronic symptoms after whiplash injuries: We could find only 3 articles in the literature. The best article, written by Algers mentions that in a series of 20 patients followed up for 4 years after surgery 2 patients had a good, 9 had a fair and 9 had poor results. I think we should all take notice of this study. Apart form surgery for the instable cervical spine there appears to be few indications for surgical treatment.