Altered motor control patterns in whiplash and chronic neck pain

Background  

Persistent whiplash associated disorders (WAD) have been associated with alterations in kinesthetic sense and motor control. The evidence is however inconclusive, particularly for differences between WAD patients and patients with chronic non-traumatic neck pain. The aim of this study was to investigate motor control deficits in WAD compared to chronic non-traumatic neck pain and healthy controls in relation to cervical range of motion (ROM), conjunct motion, joint position error and ROM-variability.     

Biomechanics of whiplash injury

Despite a large number of rear-end collisions on the road and a high frequency of whiplash injuries reported, the mechanism of whiplash injuries is not completely understood. One of the reasons is that the injury is not necessarily accompanied by obvious tissue damage detectable by X-ray or MRI. An extensive series of biomechanics studies, including injury epidemiology, neck kinematics,facet capsule ligament mechanics, injury mechanisms and injury criteria, were undertaken to help elucidate these whiplash injury mechanisms and gain a better understanding of cervical facet pain. These studies provide the following evidences to help explain the mechanisms of the whiplash injury: (1) Whiplash injuries are generally considered to be a soft tissue injury of the neck with symptoms such as neck pain and stiffness, shoulder weakness, dizziness, headache and memory loss, etc. (2) Based on kinematical studies on the cadaver and volunteers, there are three distinct periods that have the potential to cause injury to the neck. In the first stage, flexural deformation of the neck is observed along with a loss of cervical lordosis; in the second stage, the cervical spine assumes an S-shaped curve as the lower vertebrae begin to extend and gradually cause the upper vertebrae to extend; during the final stage, the entire neck is extended due to the extension moments at both ends. (3)The in vivo environment afforded by rodent models of injury offers particular utility for linking mechanics, nociception and behavioral outcomes. Experimental findings have examined strains across the facet joint as a mechanism of whiplash injury, and suggested a capsular strain threshold or a vertebral distraction threshold for whiplash-related injury,potentially producing neck pain. (4) Injuries to the facet capsule region of the neck are a major source of post-crash pain. There are several hypotheses on how whiplash-associated injury may occur and three of these injuries are related to strains within the facet capsule connected with events early in the impact. (5) There are several possible injury criteria to correlate with the duration of symptoms during reconstructions of actual crashes. These results form the biomechanical basis for a hypothesis that the facet joint capsule is a source of neck pain and that the pain may arise from large strains in the joint capsule that will cause pain receptors to fire.     

Biomechanics of whiplash injury

Despite a large number of rear-end collisions on the road and a high frequency of whiplash injuries reported, the mechanism of whiplash injuries is not completely understood. One of the reasons is that the injury is not necessarily accompanied by obvious tissue damage detectable by X-ray or MRI. An extensive series of biomechanics studies, including injury epidemiology, neck kinematics,facet capsule ligament mechanics, injury mechanisms and injury criteria, were undertaken to help elucidate these whiplash injury mechanisms and gain a better understanding of cervical facet pain. These studies provide the following evidences to help explain the mechanisms of the whiplash injury: (1) Whiplash injuries are generally considered to be a soft tissue injury of the neck with symptoms such as neck pain and stiffness, shoulder weakness, dizziness, headache and memory loss, etc. (2) Based on kinematical studies on the cadaver and volunteers, there are three distinct periods that have the potential to cause injury to the neck. In the first stage, flexural deformation of the neck is observed along with a loss of cervical lordosis; in the second stage, the cervical spine assumes an S-shaped curve as the lower vertebrae begin to extend and gradually cause the upper vertebrae to extend; during the final stage, the entire neck is extended due to the extension moments at both ends. (3)The in vivo environment afforded by rodent models of injury offers particular utility for linking mechanics, nociception and behavioral outcomes. Experimental findings have examined strains across the facet joint as a mechanism of whiplash injury, and suggested a capsular strain threshold or a vertebral distraction threshold for whiplash-related injury,potentially producing neck pain. (4) Injuries to the facet capsule region of the neck are a major source of post-crash pain. There are several hypotheses on how whiplash-associated injury may occur and three of these injuries are related to strains within the facet capsule connected with events early in the impact. (5) There are several possible injury criteria to correlate with the duration of symptoms during reconstructions of actual crashes. These results form the biomechanical basis for a hypothesis that the facet joint capsule is a source of neck pain and that the pain may arise from large strains in the joint capsule that will cause pain receptors to fire.     

Mediastinitis after whiplash injury

The authors describe a rare complication of whiplash injury. Diffuse mediastinitis resulted from extension of a whiplash-induced retropharyngeal abscess into the thorax. Early diagnosis of the cervical infection was masked by the simultaneous presence of infectious mononucleosis. Aggressive surgical management including bilateral thoracotomy was required to resolve the septic course. A review of the literature discusses the pathogenesis of this complication including the route of extension into the mediastinum and supports the use of aggressive surgical therapy to reduce the associated mortality.     

Surgery for chronic symptoms after whiplash injury: Follow-up of 20 cases

Whereas continuous exposure to PTH results in bone resorption, administration at intermittent doses results in bone formation by increasing osteoblast number and activity. The anabolic action of PTH has also been demonstrated in clinical trials, in which PTH increased the bone mass and reduced fracture rate in patients with osteoporosis. In animal models of fracture healing and fixation of orthopedic implants, PTH increases the bone density in a dose-dependent manner, leading to faster repair and better fixation. The effect appears to be stronger on the new forming bone than on pre-existing bone. Based on these preclinical studies, we suggest that intermittent PTH treatment may also benefit fracture healing and implant fixation in patients.     

颈椎挥鞭样损伤的致伤机制研究进展

随着人们生活水平的提高,汽车等交通工具已成为日常生活中不可或缺的代步工具。随之而来的交通伤不断增加,挥鞭样损伤的发生率也呈不断增长的趋势。在追尾事故中,颈椎挥鞭样损伤的发生率可达38％。英国因挥鞭样损伤造成的经济损失每年多达36．4亿英镑,     

Patterns of injury and recovery in whiplash

Whiplash injuries were studied prospectively in 151 patients. Patterns of injury and recovery were found not to depend on the type of accident. Clinical and radiological findings were correlated with the possible pathological bases for the symptoms and signs; some of these were found to be unlikely to be contributors to the clinical picture. The factors which might contribute to a delay in recovery were reviewed, and compensation claims were found not to affect outcome significantly. It is suggested that many patients have sustained an important injury, the exact nature of which remains unclear.     

Thoracic outlet syndrome in whiplash injury.

Thirty-five cases of thoracic outlet syndrome complicating whiplash or cervical strain injury were studied. Thirty cases had confirmation by the demonstration of slowed ulnar nerve conduction velocity (UNCV) through the thoracic outlet. Two distinct groups of patients were found. An acute group, seen an average of 3 1/2 months post injury, had severe neck pain with often mild or incidental thoracic outlet syndrome. A chronic group, with symptoms persisting more than 2 years after cervical injury, often had thoracic outlet symptoms as the predominant complaint. This study suggests that the arm aches and parethesias seen in association with both acute and chronic cervical strain injury are most often secondary to thoracic outlet syndrome.     

Management of chronic postoperative groin pain

Postoperative groin pain is a common complaint following surgery of the abdomen and groin. Although this pain usually resolves in the early postoperative period, some experience prolonged, debilitating pain lasting months to years. There is currently a lack of consensus as to the appropriate transition from medical to surgical management of these patients. A retrospective review of 19 consecutive patients with postoperative pain symptoms suspicious for neuropathic origin was undertaken. Neuromas or entrapment of 1 or more nerves was identified in all patients. Improvement of pain and quality of life was reported in 84%, with a minimum 1 year's follow-up. Average preoperative and postoperative pain was 7.6 and 1.2, respectively, a statistically significant reduction. This study confirms high success rates for patients surgically treated for chronic postoperative groin pain when proper selection criteria and appropriate surgical techniques are applied. A management approach is proposed and the surgical technique is described for treatment of these patients.     

Prognosis following a second whiplash injury

Five percent of the population have suffered a whiplash injury. Of these, 43% suffer long-term symptoms. We undertook a retrospective study of 79 patients who had suffered two whiplash injuries. The severity of each patient's symptoms was assessed after the first and second injuries using the Gargan and Bannister classification. Overall, 84% of patients reported increased symptoms following the second injury. Ninety-seven percent of patients who had been symptom free before the second injury reported persisting discomfort.     

Advancing imaging technologies for patients with spinal pain: with a focus on whiplash injury

Background Context

Radiological observations of soft-tissue changes that may relate to clinical symptoms in patients with traumatic and non-traumatic spinal disorders are highly controversial. Studies are often of poor quality and findings are inconsistent. A plethora of evidence suggests some pathoanatomical findings from traditional imaging applications are common in asymptomatic participants across the life span, which further questions the diagnostic, prognostic, and theranostic value of traditional imaging. Although we do not dispute the limited evidence for the clinical importance of most imaging findings, we contend that the disparate findings across studies may in part be due to limitations in the approaches used in assessment and analysis of imaging findings.

Factors affecting employment after whiplash injury

Of 586 employed patients with a whiplash injury 40 (7%) did not return to work. The risk was increased by three times in heavy manual workers, two and a half times in patients with prior psychological symptoms and doubled for each increase of grade of disability. The length of time off work doubled in patients with a psychological history and trebled for each increase in grade of disability. The self-employed were half as likely to take time off work, but recovered significantly more slowly than employees.