Are early MRI findings correlated with long lasting symptoms following whiplash injury?
From: Eur Spine J. 2008 Aug;17(8):996-1005. Epub 2008 May 30
Neck pain is the cardinal symptom following whiplash injuries. The trauma mechanism could theoretically lead to both soft tissue and bone injury that could be visualised by means of MRI. From previous quite small trials it seems that MRI does not demonstrate significant tissue damage. Large prospectively followed cohorts are needed to identify possible clinically relevant MRI findings. The objective of this trial was to evaluate (1) the predictive value of cervical MRI after whiplash injuries and (2) the value of repeating MRI examinations after 3 months including sequences with flexion and extension of the cervical spine. Participants were included after rear-end or frontal car collisions. Patients with fractures or dislocations diagnosed by standard procedures at the emergency unit were not included. MRI scans of the cervical spine were performed at baseline and repeated after 3 months. Clinical follow-ups were performed after 3 and 12 months. Outcome parameters were neck pain, headache, neck disability and working ability. A total of 178 participants had a cervical MRI scan on average 13 days after the injury. Traumatic findings were observed in seven participants. Signs of disc degeneration were common and most frequent at the C5-6 and C6-7 levels. Findings were not associated with outcome after 3 or 12 months. The population had no considerable neck trouble prior to the whiplash injury and the non-traumatic findings represent findings to be expected in the background population. Trauma related MRI findings are rare in a whiplash population screened for serious injuries in the emergency unit and not related to a specific symptomatology. Also, pre-existing degeneration is not associated with prognosis.
The influence of psychological factors on low back pain-related disability in community dwelling older persons
From: Pain Med. 2008 Oct;9(7):871-80.
To assess the influence of fear avoidance beliefs and catastrophizing on low back pain related disability in Spanish community dwelling retirees. Correlation between variables measured with previously validated instruments. Majorca, Spain: 1,044 community dwelling subjects attending conferences for retired persons. Visual analog scales for low back pain and pain referred to the leg, Roland Morris Questionnaire (RMQ) for disability, FAB-Phys questionnaire (FABQ) for fear avoidance beliefs, and the Coping Strategies Questionnaire (CSQ) for catastrophizing.
In subjects without clinically relevant low back pain, fear avoidance beliefs correlated moderately with catastrophizing and disability, and weakly with pain referred to the leg and low back pain. In subjects with low back pain, fear avoidance beliefs correlated moderately with catastrophizing and disability, and weakly with pain referred to the leg , but not with low back pain. Correlations among CSQ, FABQ, and RMQ were similar in subjects with and without current low back pain. In regression models, the coefficient for effect of fear avoidance beliefs on disability was 0.14 for participants with no low back pain, and 0.28 for those with pain. Corresponding values for catastrophizing were 0.17 and 0.19. In Spanish community dwelling retirees, the influence of fear avoidance beliefs and catastrophizing on low back pain related disability is clinically small.
Establishment of a temporomandibular physiological state with neuromuscular orthosis treatment affects reduction of TMD symptoms in 313 patients
From: Cranio. 2008 Apr;26(2):104-17
The objective of this investigation was to test the hypothesis that alteration of the occlusions of patients suffering from temporomandibular disorders (TMD) to one that is neuromuscularly, rather than anatomically based, would result in reduction or resolution of symptoms that characterize the TMD condition. This hypothesis was proven correct in the present study, where 313 patients with TMD symptoms were examined for neuromuscular dysfunction, using several electronic instruments before and after treatment intervention. Such instrumentation enabled electromyographic (EMG) measurement of the activities of the masticatory muscles during rest and in function, tracking and assessment of various movements of the mandible, and listening for noises made by the TMJ during movement of the mandible. Ultra low frequency and low amplitude, transcutaneous electrical neural stimulation (TENS) of the mandibular division of the trigeminal nerve (V) was used to relax the masticatory muscles and to facilitate location of a physiological rest position for the mandible. TENS also made it possible to select positions of the mandible that were most relaxed above and anterior to the rest position when the mandible was moved in an arc that began at rest position. Once identified, the neuromuscular occlusal position was recorded in the form of a bite registration, which was subsequently used to fabricate a removable mandibular orthotic appliance that could be worn continuously by the patient. Such a device facilitated retention and stabilization of the mandible in its new-found physiological position, which was confirmed by follow up testing. Three months of full-time appliance usage showed that the new therapeutic positions achieved remained intact and were associated with improved resting and functioning activities of the masticatory muscles. Patients reported overwhelming symptom relief, including reduction of headaches and other pain symptoms. Experts consider relief of symptoms as the gold standard for assessment of effectiveness of TMD treatment. It is evident that this outcome has been achieved in this study and that taking patients from a less to a more physiological state is an effective means for reducing or eliminating TMD symptoms, especially those related to pain, most notably, headaches.
Herniated and spondylotic intervertebral discs of the human cervical spine: histological and immunohistological findings in 500 en bloc surgical samples. Laboratory investigation
From: J Neurosurg Spine. 2008 Sep;9(3):285-95
In this paper the authors’ goal was to identify histological and immunohistochemical differences between cervical disc herniation and spondylosis. A total of 500 cervical intervertebral discs were excised from 364 patients: 198 patients with disc herniation and 166 patients with spondylosis. We examined en bloc samples of endplate ligament disc complexes. Types of herniation and graded degrees of disc degeneration on MR images were examined histologically and immunohistochemically.
The herniated discs showed granulation tissue, newly developed blood vessels, and massive infiltration of CD68-positive macrophages, which surrounded the herniated tissue mainly in the ruptured outer layer of the anulus fibrosus. The vascular invasion was most significant in uncontained (extruded)-type herniated discs. Chondrocytes positive for matrix metalloproteinase (MMP)-3, tumor necrosis factor (TNF)-alpha, basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) were abundant in both herniated and spondylotic discs. Free nerve fibers, positive for nerve growth factor (NGF), neurofilament 68, growth-associated protein (GAP)-43, and substance P, were strongly apparent in and around the outer layer of uncontained (extruded)-type herniated discs, with enhanced expression of NGF. The authors observed that herniated discs showed more advanced degeneration in the outer layer of the anulus fibrosus around the granulation tissue than spondylotic discs. On the other hand, spondylotic discs showed more advanced degeneration in the cartilaginous endplate and inner layer of the anulus fibrosus than herniated discs. Spondylotic discs also had thicker bony endplates and expressed TNFalpha and MMP-3 more diffusely than herniated discs, especially in the inner layer of the anulus fibrosus.
The authors’ results indicate that herniated and spondylotic intervertebral discs undergo different degenerative processes. It is likely that TNFa, MMP-3, bFGF, and VEGF expression is upregulated via the herniated mass in the herniated intervertebral discs, but by nutritional impairment in the spondylotic discs. Macrophage accumulation around newly formed blood vessels in the herniated disc tissues seemed to be regulated by MMP-3 and TNFalpha expression, and both herniated and spondylotic discs exhibited marked neoangiogenesis associated with increased bFGF and VEGF expression. Nerve fibers were associated with NGF overexpression in the outer layer of the anulus fibrosus as well as in endothelial cells of the small blood vessels.
Effect of physical training on function of chronically painful muscles: A randomized controlled trial
From: J Appl Physiol. 2008 Oct 23; [Epub ahead of print]
Pain and tenderness of the upper trapezius muscle is frequent in several occupational groups. The objective of this study is to investigate the effect of three contrasting interventions on muscle function and pain in women with trapezius myalgia. A group of employed women (n=42) with a clinical diagnosis of trapezius myalgia participated in a 10 week randomized controlled intervention; specific strength training of the neck and shoulder muscles (SST), general fitness training performed as leg-bicycling (GFT), or a reference intervention without physical activity (REF). Torque and electromyography (EMG) were recorded during maximal shoulder abductions in an isokinetic dynamometer at -60, 60, 0 and 180 degrees. Further, a submaximal reference contraction with only the load of the arms was performed. Results: Significant changes were observed only in specific strength training. Pain decreased 42-49%. While EMG activity of the unaffected deltoid remained unchanged during the maximal contractions, an increase in EMG amplitude (42-86%) and median power frequency (19%) were observed for the painful trapezius muscle. Correspondingly, torque increased 18-53%. EMG during the reference contraction decreased significantly for both the trapezius and deltoid muscles.
In conclusion, specific strength training relieves pain and increases maximal activity specifically of the painful trapezius muscle, leading to increased shoulder abduction strength in women with trapezius myalgia. Further, decreased relative workload may indirectly augment pain reduction.
Late Whiplash Syndrome: A Clinical Science Approach to Evidence Based Diagnosis and Management
From: Pain Practice, Volume 8, Issue 1, 2008 65–89
Late Whiplash Syndrome has been described as a disorder that is characterized by a constellation of clinical profiles including neck pain and stiffness, persistent headache, dizziness, upper limb paresthesia, and psychological emotional sequelae that persist more than 6 months after a whiplash injury. Because of the myriad of signs and symptoms with which the patient is capable of presenting, one must consider the many
possible different presentations the condition can produce.
Whiplash is the most common cause of neck pain associated with chronic musculoligamentous conditions. It is estimated that 6.2% of all Americans (approximately 15.5 million) currently suffer from Late Whiplash syndrome. Annual medical costs associated with whiplash injuries are estimated to range from $3.6 billion in the United Kingdom to $10 billion in the United States. The high incidence and exorbitant costs have elevated whiplash to international epidemic status.
Late Whiplash Syndrome involves a broad spectrum of symptoms ascribed to few other conditions or injuries
that may persist for months or years after the incident. It is estimated that only 10% of vehicle occupants exposed to a rear-end collision will develop whiplash syndrome. Of these, the incidence of chronic neck pain ranges from 18% to 40%. However, when whiplash symptoms do occur, a delay in symptom onset is expected. Selected studies have demonstrated that the delay in the onset of whiplash symptoms can range from 1 hour to several days after the accident. Moreover, patients that seek medical treatment for acute whiplash injuries face a 33% chance of developing Late Whiplash Syndrome at more than 30 months after injury. However, when presented with chronic symptoms and few causal factors, there is a tendency to suspect underlying nonorganic basis for the patient’s symptoms.
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Prolonged standing as a precursor for the development of low back discomfort: an investigation of possible mechanisms.
From: Gait Posture. 2008 Jul;28(1):86-92. Epub 2007 Nov 28.
Low back discomfort has been associated with prolonged periods of standing, yet research has shown that the magnitude of spinal loading during standing is relatively minimal. Therefore, the mechanism of this discomfort is not fully understood. Research has monitored numerous variables during prolonged periods of standing; however the focus of this work has been primarily on the comparison of the effect of different floor surfaces on these variables. No study to date has made an attempt to relate these changes to the development of low back discomfort. The purpose of this study was therefore to determine possible mechanisms for the development of low back discomfort during standing by monitoring biological variables. It was hypothesized that during a prolonged standing period, low back discomfort would develop and the measured variables would change over time. Sixteen individuals stood for 2h while activation of torso and hip muscles, lumbar spine posture, back extensor muscle oxygenation, torso skin temperature, and centre of pressure changes under the feet were monitored over time. Thirteen out of sixteen individuals developed low back discomfort as a result of the prolonged standing period, which significantly increased over the 2-h period. Only three of the 37 variables measured were significantly altered over time. However, a generated regression model incorporating 15 of the 16 individuals (which incorporated how each individual stood in the first 15 min) explained 78% of the variance in low back discomfort at the end of the 2-h standing period. Prolonged standing resulted in low back discomfort, yet few significant changes in the measured variables were observed over time. It is possible that low back discomfort is not linked with alterations in standing over time, but rather associated with how an individual initially stands.
Clinimetric evaluation of methods to measure muscle functioning in patients with non-specific neck pain: a systematic review
From: BMC Musculoskelet Disord. 2008 Oct 19;9(1):142 [Epub ahead of print]
Neck pain is a common but significant health problem in modern society, with reported 1-year prevalence values in the world population varying from 16.7% to 75.1% for adults, with a mean of 37.2%. Annual incidence rates of neck pain in general practice in the Netherlands have been estimated at 23 of every 1000 persons registered with a GP. The incidence rates increase with age up to 40 to 60 years, and then decrease slightly. Neck pain is generally more common in women than in men. It often has a continuous or intermittent course. Approximately 30% of people with neck pain face restrictions in their activities of daily living. In the Netherlands, 51% of patients with acute non-specific neck pain who consult their general practitioners are referred to musculoskeletal practitioners for treatment.
It is estimated that the neck musculature contributes about 80% to the mechanical stability of the cervical spine, while the osseoligamentous system contributes the remaining 20%. There is evidence to suggest that patients with neck pain have reduced maximal isometric neck strength and endurance capacity. Furthermore, jerky and irregular neck movements and poor position sense acuity have been found in patients with chronic neck pain. Musculoskeletal practitioners apply various treatment modalities to treat patients with non specific neck pain. Exercises are commonly used to improve neck muscle function and thereby decrease pain or other symptoms. Evaluating the progress of neck muscle function during treatment requires tests which can be carried out easily and meet certain standards for clinimetric properties.
A 2001 review of the reliability and validity of neck muscle strength, endurance and proprioception concluded that there was a lack of reliable and valid instruments to measure strength, endurance and proprioception. This review did not formulate any criteria for quality assessment, and although it included all the instruments suitable for measuring neck muscle function, it did not address cost, practicality and use of the tests. In the present review we have included only those instruments that can be easily used in daily practice (maximum of 5 minutes required for testing) and that are affordable (maximum 1000 euros). The purpose of this literature review is thus to summarise the clinimetric properties of the tests or instruments for neck muscle function in patients with neck pain which can be easily applied in daily practice.
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Hypoesthesia occurs in acute whiplash irrespective of pain and disability levels and the presence of sensory hypersensitivity
From: Clin J Pain. 2008 November/December;24(9):759-766
In contrast to the increasing knowledge of the sensory dysfunction involved in chronic whiplash associated disorders, the use of comprehensive quantitative sensory testing in the acute stage of the condition is sparse. In this study, we sought to investigate the presence of sensory hypoesthesia in participants with acute whiplash injury. Fifty-two volunteers within 4 weeks after a motor vehicle accident and 31 healthy asymptomatic volunteers were recruited for this study. We classified our cohort into either a high risk (signs associated with poor recovery including Neck Disability Index scores greater than 30, cold and mechanical hyperalgesia, heightened brachial plexus provocation test responses) or low risk group (without these signs). Detection thresholds to electrical, thermal, and vibration stimuli measured in lower cervical nerve root innervation zones and psychologic distress and posttraumatic stress symptoms were compared between the groups using multivariate analysis of covariance.
Both the high risk and low risk groups exhibited significant elevation in sensory detection when compared with controls. There was no difference in detection thresholds between the 2 whiplash groups, except for electrical detection which was greater in the high risk group. Both groups were psychologically distressed. Our findings demonstrate generalized hypoesthesia in acute whiplash associated disorders suggesting adaptive central nervous system processing mechanisms are involved, regardless of pain and disability. The elevated levels of psychologic distress seen in both groups may also play a role.
Analysis of magnetic resonance imaging characteristics and pain in temporomandibular joints with and without degenerative changes of the condyle
From: Int J Oral Maxillofac Surg. 2008 Jun;37(6):529-34. Epub 2008 Apr 28
The aim of this study was to investigate temporomandibular joint (TMJ) pain and magnetic resonance imaging characteristics in 104 TMJs with and 58 without degenerative changes of the condyle, such as osteophytes, erosion, avascular necrosis, subcondral cyst and intra-articular loose bodies. TMJ images were also assessed for flattening, retropositioning and hypomobility of condyle and disc displacement. Comparison of the TMJ side-related data showed a significant relationship between disc displacement without reduction and the presence of degenerative bony changes. Flattening, retropositioning and hypomobility of condyle showed no significant difference in relation to the presence or absence of degenerative bony changes. Retropositioning of the condyle was significantly associated to disc displacement, while condylar hypomobility was significantly more frequent in TMJ. Independent of the presence or type of DD, TMJ pain was more frequent in the presence of degenerative bony changes. When considering only disc displacement with reduction, TMJ pain was significantly associated to a degenerative condition. When there were no degenerative bony changes, TMJ pain was significantly more frequent in disc displacement without reduction. Despite the present findings, the absence of symptoms in some patients with condylar bony changes suggests that the diagnosis of osteoarthritis should be established by evaluation of magnetic resonance images in association with clinical examination.
