TOMOGRAPHIC ANALYSIS FOR C2 SCREW PLACEMENT IN RHEUMATOID ARTHRITIS PATIENTS

Objective: A morphological analysis of the bone structure of 02 in patients with rheumatoid arthritis in order to enhance the security of the stabilization procedures for this vertebra. Methods: We retrospectively analyzed 20 CT scans of the cervical spine performed in patients with rheumatoid arthritis; the following parameters were measured: spinolaminar angle, thickness and length of C2 lamina. Results: The mean values are: 5.92mm and 5.87mm for thickness of right and left laminae retrospectively, 27.75mm for right lamina length and 27.94mm for left lamina length, and 44.7 degrees for spinolaminar angle. Conclusion: The values obtained are consistent with studies in normal subjects published by other groups, with no apparent need for change in the screw placement technique. Level of Evidence IV, Case Series.

RESULTS OF ULNAR NERVE NEUROTIZATION TO BICEPS BRACHII MUSCLE IN BRACHIAL PLEXUS INJURY

Objective: To evaluate the factors influencing the results of ulnar nerve neurotization at the motor branch of the brachii biceps muscle, aiming at the restoration of elbow flexion in patients with brachial plexus injury. Methods: 19 patients, with 18 men and 1 woman, mean age 28.7 years. Eight patients had injury to roots C5-C6 and 11, to roots C5-C6-C7. The average time interval between injury and surgery was 7.5 months. Four patients had cervical fractures associated with brachial plexus injury. The postoperative follow-up was 15.7 months. Results: Eight patients recovered elbow flexion strength MRC grade 4; two, MRC grade 3 and nine, MRC <3. There was no impairment of the previous ulnar nerve function. Conclusion: The surgical results of ulnar nerve neurotization at the motor branch of brachii biceps muscle are dependent on the interval between brachial plexus injury and surgical treatment, the presence of associated fractures of the cervical spine and occipital condyle, residual function of the C8-T1 roots after the injury and the involvement of the C7 root. Signs of reinnervation manifested up to 3 months after surgery showed better results in the long term. Level of Evidence: IV, Case Series.

The role of tissue damage in whiplash-associated disorders: discussion paper 1

Nonsystematic review of cervical spine lesions in whiplash-associated disorders (WAD).

Dystonic movement disorders and spinal degenerative disease

The occurrence of degenerative spinal disease subsequent to dystonic movement disorders has been neglected and has received more attention only recently. Spinal surgery is challenging with regard to continuous mechanical stress when treatment of the underlying movement disorder is insufficient. To characterize better the particular features of degenerative spinal disease in patients with dystonia and to analyze operative strategies, we reviewed the available published data. Epidemiologic studies reveal that degenerative spinal disorders in patients with dystonia and choreoathetosis occur much earlier than in the physiological aging process. Dystonic movement disorders more often affect the spine at higher cervical levels (C(2-5)), in contrast to spinal degeneration with age which manifests more frequently at the middle and lower cervical spine (C(5-7)). Degenerative changes of the cervical spine are more likely to occur on the side where the chin is rotated or tilted to. Various operative approaches for treatment of spinal pathologies have been advocated in patients with dystonic movement disorders. The available data do not allow making firm statements regarding the superiority of one approach over the other. Posterior approaches were first used for decompression, but additional anterior fusion became necessary in many instances. Anterior approaches with or without instrumented fusion yielded more favorable results, but drawbacks are pseudarthrosis and adjacent-level disease. Parallel to the development of posterior fusion techniques, circumferential surgery was suggested to provide a maximum degree of cord decompression and a higher fusion rate. Perioperative local injections of botulinum toxin were used initially to enhance patient comfort with halo immobilization, but they are also applied in patients without external fixation nowadays. Treatment algorithms directed at the underlying movement disorder itself, taking advantage of new techniques of functional neurosurgery, combined with spinal surgery have recently been introduced and show promising results.

Closed-loop control of mean arterial blood pressure during surgery with alfentanil: clinical evaluation of a novel model-based predictive controller

BACKGROUND: In contrast to hypnosis, there is no surrogate parameter for analgesia in anesthetized patients. Opioids are titrated to suppress blood pressure response to noxious stimulation. The authors evaluated a novel model predictive controller for closed-loop administration of alfentanil using mean arterial blood pressure and predicted plasma alfentanil concentration (Cp Alf) as input parameters. METHODS: The authors studied 13 healthy patients scheduled to undergo minor lumbar and cervical spine surgery. After induction with propofol, alfentanil, and mivacurium and tracheal intubation, isoflurane was titrated to maintain the Bispectral Index at 55 (+/- 5), and the alfentanil administration was switched from manual to closed-loop control. The controller adjusted the alfentanil infusion rate to maintain the mean arterial blood pressure near the set-point (70 mmHg) while minimizing the Cp Alf toward the set-point plasma alfentanil concentration (Cp Alfref) (100 ng/ml). RESULTS: Two patients were excluded because of loss of arterial pressure signal and protocol violation. The alfentanil infusion was closed-loop controlled for a mean (SD) of 98.9 (1.5)% of presurgery time and 95.5 (4.3)% of surgery time. The mean (SD) end-tidal isoflurane concentrations were 0.78 (0.1) and 0.86 (0.1) vol%, the Cp Alf values were 122 (35) and 181 (58) ng/ml, and the Bispectral Index values were 51 (9) and 52 (4) before surgery and during surgery, respectively. The mean (SD) absolute deviations of mean arterial blood pressure were 7.6 (2.6) and 10.0 (4.2) mmHg (P = 0.262), and the median performance error, median absolute performance error, and wobble were 4.2 (6.2) and 8.8 (9.4)% (P = 0.002), 7.9 (3.8) and 11.8 (6.3)% (P = 0.129), and 14.5 (8.4) and 5.7 (1.2)% (P = 0.002) before surgery and during surgery, respectively. A post hoc simulation showed that the Cp Alfref decreased the predicted Cp Alf compared with mean arterial blood pressure alone. CONCLUSION: The authors' controller has a similar set-point precision as previous hypnotic controllers and provides adequate alfentanil dosing during surgery. It may help to standardize opioid dosing in research and may be a further step toward a multiple input-multiple output controller.

3D C-arm as an alternative modality to CT in postmortem imaging: technical feasibility

OBJECT: The aim of our study was to demonstrate the image quality of the new device using human cadavers, extending the horizon of available imaging modalities in forensic medicine. MATERIALS AND METHODS: Six human cadavers were examined, revealing C-arm data sets of the head, neck thorax, abdomen and pelvis. High-resolution mode was performed with 500 fluoroscopy shots during a 190 degrees orbital movement with a constant tube voltage of 100 kV and a current of 4.6 mA. Based on these data sets subsequent three-dimensional reconstructions were generated. RESULTS: Reconstructed data sets revealed high-resolution images of all skeletal structures in a near-CT quality. The same image quality was available in all reconstruction planes. Artefacts caused by restorative dental materials are less accentuated in CBCT data sets. The system configuration was not powerful enough to generate sufficient images of intracranial structures. CONCLUSION: After the here-demonstrated encouraging preliminary results, the forensic indications that would be suitable for imaging with a 3D C-arm have to be defined. Promising seems the visualization local limited region of interest as the cervical spine or the facial skeleton.

Course of psychological variables in whiplash injury--a 2-year follow-up with age, gender and education pair-matched patients

This study evaluated the course of psychological variables during a 2-year follow-up in patients after common whiplash of the cervical spine. From a sample of 117 non-selected patients with common whiplash (investigated on average 7.2 +/- 4.2 days after trauma) a total of 21 suffered trauma-related symptoms over 2 years following initial injury. These patients (symptomatic group) were compared with 21 age, gender and education pair-matched patients, who showed complete recovery from trauma-related symptoms during the 2-year follow-up (asymptomatic group). Both groups underwent standardised testing procedures (i.e., Freiburg Personality Inventory and Well-Being Scale) at referral, and at 3, 6 and 24 months. In the symptomatic group during follow-up no significant changes in rating of neck pain or headache were found. Significant differences between the groups and significant deviation of scores over time were found on the Well-Being and Nervousness Scales. There was a lack of significant difference between the groups on the Depression Scale, indicating a possible somatic basis for changes in psychological functioning in the investigated sample. With regard to scales of Extraversion or Neuroticism, there were neither significant differences between the groups nor significant deviation over time. These results highlight that patients' psychological problems are rather a consequence than a cause of somatic symptoms in whiplash.

Surgical approach for synovial cyst of the atlantoaxial joint: a case report and review of the literature

STUDY DESIGN: Case report and review of the literature. OBJECTIVE: We describe the first case of a synovial cyst arising from pseudarthrosis of a previous dens fracture. The literature is reviewed and etiological, diagnostic, and therapeutic options of atlantoaxial cysts are discussed. SUMMARY OF BACKGROUND DATA: Symptomatic synovial cysts of the atlantoaxial joint are rare. To the authors' knowledge only 24 cases have been reported.A 60-year-old patient presented with bilateral hand numbness, quadrihyperreflexia, and gait deterioration. Magnetic resonance imaging of the cervical spine disclosed a cystic mass located at the transverse ligament of dens axis causing bulbomedullary compression. METHODS: Surgery was performed via transoral image guided approach. The ventral atlas arch, dens, transverse ligament, tectorial membrane, and the compressing cyst were removed, followed by a C0-C3 fusion. RESULTS: Two months postsurgery the patient recovered completely from the cervical myelopathy with transient remnant dysparesthesia of the finger tips. CONCLUSION: Magnetic resonance imaging findings are not specific enough to establish a preoperative diagnosis. Radical resection via image-guided transoral route followed by posterior fusion allows complete resection of the cystic lesion and results in excellent long-term decompression.

Cement-augmented anterior screw fixation of Type II odontoid fractures in elderly patients with osteoporosis

BACKGROUND CONTEXT: Closed reduction and internal fixation by an anterior approach is an established option for operative treatment of displaced Type II odontoid fractures. In elderly patients, however, inadequate screw purchase in osteoporotic bone can result in severe procedure-related complications. PURPOSE: To improve the stability of odontoid fracture screw fixation in the elderly using a new technique that includes injection of polymethylmethacrylat (PMMA) cement into the C2 body. STUDY DESIGN: Retrospective review of hospital and outpatient records as well as radiographs of elderly patients treated in a university hospital department of orthopedic surgery. PATIENT SAMPLE: Twenty-four elderly patients (8 males and 16 females; mean age, 81 years; range, 62-98 years) with Type II fractures of the dens. OUTCOME MEASURES: Complications, cement leakage (symptomatic/asymptomatic), operation time, loss of reduction, pseudarthrosis and revision surgery, patient complaints, return to normal activities, and signs of neurologic complications were all documented. METHODS: After closed reduction and anterior approach to the inferior border of C2, a guide wire is advanced to the tip of the odontoid under biplanar fluoroscopic control. Before the insertion of one cannulated, self-drilling, short thread screws, a 12 gauge Yamshidi cannula is inserted from anterior and 1 to 3 mL of high-viscosity PMMA cement is injected into the anteroinferior portion of the C2 body. During polymerization of the cement, the screws are further inserted using a lag-screw compression technique. The cervical spine then is immobilized with a soft collar for 8 weeks postoperatively. RESULTS: Anatomical reduction of the dens was achieved in all 24 patients. Mean operative time was 64 minutes (40-90 minutes). Early loss of reduction occurred in three patients, but revision surgery was indicated in only one patient 2 days after primary surgery. One patient died within the first eight postoperative weeks, one within 3 months after surgery. In five patients, asymptomatic cement leakage was observed (into the C1-C2 joint in three patients, into the fracture in two). Conventional radiologic follow-up at 2 and 6 months confirmed anatomical healing in 16 of the19 patients with complete follow-up. In two patients, the fractures healed in slight dorsal angulation; one patient developed a asymptomatic pseudarthrosis. All patients were able to resume their pretrauma level of activity. CONCLUSIONS: Cement augmentation of the screw in Type II odontoid fractures in elderly patients is technically feasible in a clinical setting with a low complication rate. This technique may improve screw purchase, especially in the osteoporotic C2 body.

Shaking head means "no"

A 45-year-old man was admitted to the emergency department because of twitching of the head. The patient took a tablet of sumatriptan every 3-4 h because of increasing head pain after a car accident. Owing to depression, the patient was on long-term treatment with venlafaxine. The patient presented as hypertensive, tachycardic, with dyskinesia and spontaneous myoclonic movements of the right sternocleidomastoid muscle. In a CT scan of the head and cervical spine any fractures, bleeding or damage of the vessels after the accident could be ruled out. After discontinuation of all serotonergic agents, administration of lorazepam symptoms resolved 24 h after the last intake of sumatriptan. Serotonin syndrome is a clinical diagnosis, which requires a high-index of diagnostic suspicion. Clinical features include a broad spectrum of symptoms ranging from mild to life-threatening manifestations. Management is based on removal of precipitating drugs and symptomatic care including benzodiazepines.

Atlanto-axial rotatory subluxations in postmortem CT: radiologists be aware of a common pitfall

The aim of the present study was to determine the frequency of atlanto-axial rotatory subluxations (AARS) in multi detector computed tomography (MDCT) performed on human corpses for forensic purposes and to investigate whether these are a physiological postmortem finding or indicate a trauma to the neck region. 80 forensic cases examined with MDCT from November 2003 to March 2007 were included in the study. The study was approved by the regional ethics committee. For each case volumes were rendered and investigated with reference to suspected AARS and any other anomalies of the head and neck region. The rotation of the head as well as in the atlanto-axial joint were measured and occurring AARS were judged according Fielding's classification. The finding of AARS was correlated to case criteria such as postmortem head rotation, sex, age, cause of death, time since death and further autopsy results. Statistical analysis was performed using Fisher's exact test, Wilcoxon's rank sums test and Chi-square test with Pearson approximation. 70% (n=56) of the cases included in the study presented with an AARS. A strong correlation (P<.0001) between suspected AARS and postmortem head rotation was found. Two cases presented with an atlanto-axial rotation greater than the head rotation. One showed an undiscovered lateral dislocation of the atlas, and one an unfused atlas-ring. There was no correlation to any further investigated case criteria. Ipsilateral AARS with head rotation alone does not indicate trauma to the neck. PmCT can substantially support forensic examinations of the skeleton, especially in body regions, which are elaborate to access at autopsy, such as the cervical spine. Isolated AARS (Fielding type I) on pmCT is usually a normal finding associated with ipsilateral head rotation.

MRI findings in a case of canine tick born meningoencephalomyelitis

Tick borne encephalitis virus (TBE) is an endemic infectious agent in northeastern Switzerland causing mainly meningoencephalomyelitis in dogs. We report a canine case of tick born meningoencephalomyelitis resulting in flaccid tetraplegia and, subsequently, fatal respiratory failure. Magnetic resonance imaging (MRI) demonstrated intra-axial bilateral, symmetric, and hyperintense lesions in T2-weighted and Fluid Attenuated Inversion Recovery (FLAIR) sequences affecting thalamus, basal nuclei, cerebral white matter and ventral horns of the caudal cervical spine. These radiological findings overlap those described during flavivirus encephalitis affecting human beings. These lesions in MRI and diffusion weighted images correlated with areas of vasogenic edema detected histopathologically. In endemic regions, clinicians should be aware that bilateral, symmetrical hyperintense thalamic lesions in T2WI can be suggestive of flavivirus infection in dogs with encephalitis

Mucosal Erosion of the Cricoid Cartilage After the Use of an i-Gel Supraglottic Airway Device in a Patient with Diffuse Idiopathic Skeletal Hyperostosis

After standard hip arthroplasty, an 82-year-old patient with previously undiagnosed diffuse idiopathic skeletal hyperostosis of the cervical spine experienced life-threatening side effects after use of a supraglottic airway device (i-gel). Extensive mucosal erosion and denudation of the cricoid cartilage caused postoperative supraglottic swelling and prolonged respiratory failure requiring tracheostomy. In this case report, we highlight the importance of evaluating risk factors for failure of supraglottic airway devices.

Unravelling the complexity of muscle impairment in chronic neck pain

Exercise interventions are deemed essential for the effective management of patients with neck pain. However, there has been a lack of consensus on optimal exercise prescription, which has resulted from a paucity of studies to quantify the precise nature of muscle impairment, in people with neck pain. This masterclass will present recent research from our laboratory, which has utilized surface electromyography to investigate cervical flexor muscle impairment in patients with chronic neck pain. This research has identified deficits in the motor control of the deep and superficial cervical flexor muscles in people with chronic neck pain, characterized by a delay in onset of neck muscle contraction associated with movement of the upper limb. In addition, people with neck pain demonstrate an altered pattern of muscle activation, which is characterized by reduced deep cervical flexor muscle activity during a low load cognitive task and increased activity of the superficial cervical flexor muscles during both cognitive tasks and functional activities. The results have demonstrated the complex, multifaceted nature of cervical muscle impairment, which exists in people with a history of neck pain. In turn, this has considerable implications for the rehabilitation of muscle function in people with neck pain disorders. (C) 2004 Elsevier Ltd. All rights reserved.

Spatio-temporal evaluation of neck muscle activation during postural perturbations in healthy subjects

The purpose of this study was to examine the spatio-temporal activation of the sternocleidomastoid (SCM) and cervical extensor (CE) muscles with respect to the deltoid muscle onset during rapid voluntary upper limb movement in healthy volunteers. The repeatability and reliability of the spatio-temporal aspects of the myoelectric signals were also examined. Ten subjects performed bilateral and unilateral rapid upper limb flexion, abduction and extension in response to a visual stimulus. EMG onsets and normalised root mean square (nRMS) values were calculated for the SCM and CE muscles. Subjects attended three testing sessions over non-consecutive days allowing the repeatability and reliability of these measures to be assessed. The SCM and CE muscles demonstrated feed-forward activation (activation within 50 ms of deltoid onset) during rapid arm movements in all directions. The sequence and magnitude of neck muscle activation displayed directional specificity, however, the neck flexor and extensor muscles displayed co-activation during all perturbations. EMG onsets demonstrated high repeatability in terms of repeated measure precision (nSEM in the range 1.9-5.7%). This was less evident for the repeatability of nRMS values. The results of this study provide a greater understanding of cervical neuromotor control strategies. During bilateral and unilateral upper limb perturbations, the SCM and CE muscles demonstrate feed-forward co-activation. It seems apparent that feed-forward activation of neck muscles is a mechanism necessary to achieve stability for the visual and vestibular systems, whilst ensuring stabilisation and protection of the cervical spine. (C) 2004 Elsevier Ltd. All rights reserved.