C2 Spinous Process Research Articles

Optimal inertial sensor location for ambulatory measurement of trunk inclination

Trunk inclination (TI) is used often to quantify back loading in ergonomic workplace evaluation. The aim of the present study was to determine whether TI can be obtained using a single inertial sensor (IS) on the back, and to determine the optimal IS location on the back for the estimation of TI. Gold standard TI, the angle between the vertical and the line connecting the L5/S1 joint and the trunk centre of mass, was measured using an optoelectronic system. Ten subjects performed experimental trials, each consisting of a symmetric and an asymmetric lifting task, and of a left–right lateral flexion movement. Trials were repeated and, in between trials, the IS was shifted in small steps from a location on the thorax towards a location on the sacrum. Optimal IS location was defined as the IS location with minimum root-mean-square (RMS) error between the gold standard TI and the IS TI. Averaged over subjects, the optimal IS location for symmetric and asymmetric lifting was at about 25% of the distance from the midpoint between the posterior superior iliac spines (MPSIS) to the C7 spinous process. The RMS error at this location, averaged over subjects, was 4.6±2.9°. For the left–right lateral flexion task, the optimal IS location was at about 30% of the MPSIS to C7 distance. Because in most activities of daily living, pure lateral flexion does not occur often, it is recommended place the IS at 25% of the distance from the MPSIS to C7.

Modification of Wright’s technique for C2 translaminar screw fixation: technical note

To describe a modification of Wright's technique for C2 translaminar screw fixation. Bilateral crossing C2 laminar screws have recently become popular as an alternative technique for C2 fixation. This technique is particularly useful in patients with anomalous anatomy, as a salvage technique where other modes of fixation have failed or as a primary procedure. However, reported disadvantages of this technique include breach of the dorsal lamina and spinal canal, early hardware failure and difficulty in bone graft placement due to the position of the polyaxial screw heads. To address some of these issues, a modified technique was used in six patients. In this technique, the upper part of the spinous process of C2 was removed and the entry point of the screw was in the base of this removed spinous process. The screw position was satisfactory in all patients. There were no intraoperative or early postoperative complications. Our modification enables placement of a bone graft on the C2 lamina and is also less likely to cause inadvertent cortical breach. Because of these advantages, it is especially suitable for patients with advanced rheumatoid arthritis with destruction of the lateral masses of C2 or as part of a hybrid construct in patients with a unilateral high-riding vertebral artery. This technique is not suitable for bilateral translaminar screw placement.

Characterization of a novel C8 phasic muscle stretch reflex

Muscle stretch reflexes (MSRs) are fundamental to the neurologic examination. Although the fifth, sixth, and seventh cervical roots have appropriate and easily elicited MSRs, the C8 level does not. The C8 reflex is obtained by tapping the thenar eminence, which produces flexion at the interphalyngeal joints of the fingers. To confirm that finger flexion represented an MSR, an externally triggered hammer-skin contact set-up was employed. Surface recording electrodes were placed at one third of the distance between the medial epicondyle and ulnar styloid. This montage produced distinct T-waves with latencies compatible with a reflex arc. Normative data were collected for 75 healthy subjects (150 arms), including 15 from each of five age groups (20-29, 30-39, 40-49, 50-59, > or =60 years). Distance 1 (D1) was measured from the FPL to the C7 spinous process and distance 2 (D2) from C7 to the G1 electrode. A high median neuropathy abolished the T-wave. A distal median nerve block at the carpal tunnel had no effect. Mean latencies (+/- SD) from the respective age groups were as follows: 21.73 +/- 1.16 ms; 22.50 +/- 1.70 ms; 22.19 +/- 1.52 ms; 22.66 +/- 2.13 ms; and 23.97 +/- 1.91 ms. Reflex latencies significantly correlated with age (r = 0.33, P = 0.004), height (r = 0.51, P < 0.0001), and D1 + D2 or arc length (r = 0.74, P < 0.0001). This novel MSR is generated from the FPL tendon and stimulates contraction of the long finger flexors. It therefore represents a clinically useful C8 MSR.

Transcutaneous electrical nerve stimulation and transcutaneous spinal electroanalgesia: A preliminary efficacy and mechanisms-based investigation

Objectives To determine the effects of transcutaneous electrical nerve stimulation (TENS) and transcutaneous spinal electroanalgesia (TSE) on mechanical pain threshold (MPT) and vibration threshold (VT). Design A prospective, single-blind, randomised, placebo-controlled trial. Setting Laboratory based. Participants Thirty-four healthy volunteers (12 men and 22 women; mean age ± standard deviation 30 ± 8 years). Exclusion criteria were conditions affecting upper limb sensation and contraindications to electrical stimulation. Interventions Participants were allocated at random to receive TENS ( n = 8), TSE ( n = 8), placebo ( n = 9) or control ( n = 9). Electrical stimulation was applied for 30 minutes (from time 18 minutes to 48 minutes) via electrodes (5 cm × 5 cm) placed centrally above and below the space between the C6 and C7 spinous processes, with 5 cm between electrodes. Main outcome measures MPT (using an algometer) and VT (using a vibrameter) were recorded on seven occasions from the first dorsal interosseous muscle of the right hand – at baseline (0 minutes) and then at 10-minute intervals until the end of the 60-minute testing period. Results There were no statistically significant group differences in MPT (all p > 0.05). Significant group differences in VT were found at 20, 30 and 40 minutes (all p < 0.05). Post-hoc tests showed that the TENS group had significantly greater VT than both the placebo [median difference 0.30 μm, 95% confidence interval (CI) −0.05 to 0.66] and control (0.51 μm, 95% CI 0.05 to 0.97) groups at 20 minutes, and significantly greater VT than the control group (0.69 μm, 95% CI 0.20 to 1.17) at 30 minutes (all p < 0.008). Conclusions Electrical stimulation did not alter MPT. The increase in VT during TENS may be due to distraction or antidromic block of large-diameter nerve fibres. TSE failed to alter either outcome measure significantly.

Direct posterior reduction and fixation for the treatment of idiopathic atlantoaxial dislocation

Objective To report our surgical technique and results in the treatment of idiopathic atlantoaxial dislocation (IAAD) by using direct posterior reduction and fixation, without odontoidectomy and cervical traction. Methods Twenty patients of IAAD were operated on during May 2004 to December 2007. Before and after the operation, CT and MRI were used to measure and evaluate the degree of dislocation and neural compression. Two different screw fixation techniques were used depending on whether there was C1 assimilation; C1 lateral mass - C2 pedicle screws fixation was used for patients without C1 assimilation, otherwise, C2 pedicle -Occiput scews fixation was used. Intraoperative reduction was achieved by compressing the C2 spinous process anteriorly, or by distraction between C2 pedicle and occiput screws. Results All 20 patients were followed up from 6 to 48 months, among them, there was one death due to basilar artery thrombosis one week after the operation; in all the other 19 patients, symptoms were relieved markedly. All the postoperative radiological measurements were improved significantly (paired t test, in all groups, P < 0. 01 ). MRI showed good decompression of spinal cord and oblongata medulla in all 19 cases (CMA, P < 0.01 ); in 5 patients associated with Chiari's malformation and syringomyelia, syrinx was significantly shrinked in all patients. Conclusion Using posterior approach and intraoperative reduction and fixation technique, rather than anterior decompression through transoral odontoidectomy, for the treatment of IAAD is an effective, simple and relatively safe method. Key words: Atlantoaxial dislocation; Basilar invagination; Reduction; Fixation

Preserving the C7 spinous process with its muscles attached: effect on axial symptoms after cervical laminoplasty

BackgroundMany efforts to reduce axial symptoms after cervical laminoplasty have been tried and reported; nevertheless, avoiding the axial symptoms has not yet been solved. There have been some reports that preserving the muscles attached to the C7 spinous process could reduce axial symptoms. The purpose of this study was to investigate whether axial symptoms can be reduced by preserving the C7 spinous process with its muscles attached during cervical laminoplasty. MethodsA series of 21 patients (group A) with C4-6 lami-noplasty, preserving the C7 spinous process and its attached muscles, were compared with 22 patients (group B) with C4-7 laminoplasty. The axial symptoms (incidence, intensity, severity), cervical mobility, cervical curvature morphology, crosssectional area of posterior cervical muscles, and Japanese Orthopaedic Association (JOA) score were evaluated. ResultsThere were no significant differences in incidence, intensity, or severity of axial symptoms 1 year after operation, in addition, there were no significant differences in the cervical mobility or curvature morphology, the cross-sectional area of the posterior cervical muscles, or the JoA score. ConclusionsThese results suggest that both preserving and not preserving the C7 spinous process with its muscles attached during cervical laminoplasty are acceptable in the long term.

Biomechanical Assessment Of Canadian Military Soft Armor Systems

Due to the nature of the threat from Improvised Explosive Devices (IED), the pattern and probability of injury has changed for both mounted and dismounted military personnel. This work was performed for the Soldier System Integration Group at Defense Research and Development Canada (DRDC)-Toronto in support of the Counter Improvised Explosive Device (C-IED) Technical Demonstration Project (TDP). PURPOSE: 1) To quantitatively assess three different designs of military soft armour systems that provide the same level of ballistic protection, yet differ in stiffness, bulk and weight; 2) To compare subjective data from soldiers' preferences with electromyography (EMG) and range of motion (ROM) data. METHODS: Eight male Canadian Armed Forces personnel participated in this investigation. Surface EMG data were recorded from eight muscles on the subjects' dominant side including: the Biceps (bilaterally), Triceps, Anterior Deltoid, Pectoralis Major, Trapezius, External Oblique (bilaterally). Upper body kinematics were recorded using seven MTx inertial motion sensors (Xsens, Netherlands) placed on the head, the C7 spinous process, the sacrum (L5/S1), as well as the upper and lower arms (bilaterally). Muscle activity and joint range of motion were assessed for a total of three different soft armour systems across a battery of upper body & trunk range of motion tasks. In addition soldiers were asked to complete a questionnaire at the end of test session, requiring them to rank each of the armour systems from best to worst in terms of overall maneuverability. RESULTS: Results from this investigation indicate that this approach of combining EMG concurrently with ROM is able to provide an objective biomechanical assessment of personal protective equipment. The EMG and ROM objective measures were all positively correlated to soldiers' subjective responses using a Spearman's Ranked Correlation Test. These correlations were particularly strong for the shoulder region ROM tasks (RS =1.0 for all three comparisons). CONCLUSION: Results indicate that less stiff, less bulky, and lighter systems are deemed superior for dynamic tasks, whereas, stiffer, bulkier, and heavier systems may have advantages for static holding tasks. Research Funded by DRDC-Toronto.

The validity of Rehabilitative Ultrasound Imaging for measurement of trapezius muscle thickness

The purpose of the study was to establish the validity of Rehabilitative Ultrasound Imaging (RUSI) against Magnetic Resonance Imaging (MRI) for measuring trapezius muscle thickness. Participants were asymptomatic subjects recruited from Trinity College Dublin and associated teaching hospitals. Four MRI axial slices were made through each of the C6, T1, T5 and T8 spinous processes, with the subject supine. RUSI was performed immediately after MRI at the same vertebral levels, with the subject prone. Linear measurements of trapezius muscle thickness were made off-line on both the MRI and Ultrasound scans, in three regions: lower, middle and upper trapezius. Bland and Altman limits of agreement and Pearson's correlation coefficient were used to analyse the relationship between thickness measures taken from MRI and RUSI. Eighteen subjects (9 women) participated, (age-range 21–42 years). Results demonstrated good agreement between MRI and RUSI measurements of the lower trapezius muscle at T8 ( r = 0.77) and moderate agreement at T5, ( r = 0.62). Results were poor for the middle (T1) and upper (C6) trapezius muscles, ( r = −0.22 to 0.52) but may be explained by differences in both positioning and imaging planes between the 2 modalities. It was concluded that RUSI is a valid method of measuring lower trapezius muscle thickness.

Complete Aplasia of the Posterior Arch of the Atlas with Bifid C7 Spinous Process: A Case Report

Complete Aplasia of the Posterior Arch of the Atlas with Bifid C7 Spinous Process: A Case Report

Forces Applied to the Cervical Spine During Posteroanterior Mobilization

Objective There is little information on manual forces applied during cervical mobilization, a common treatment technique. Potential variability of applied forces between therapists and treatment occasions, and factors associated with different force applications are unknown. The purpose of this study is to establish the baseline mechanical properties of cervical spine mobilization and to determine if the applied forces are affected by the characteristics of therapists and mobilized subjects. Methods Physiotherapists (n = 116) applied 4 grades of posteroanterior mobilization to the premarked C2 and C7 spinous (central technique) and articular processes (unilateral technique, one right and one left) of 1 of 35 asymptomatic subjects. Techniques were performed in randomized order, and the first one was repeated after 20 minutes. Load cells attached to the treatment table recorded forces in 3 directions. Before mobilization, subjects' spinal stiffness at the C2 and C7 spinous processes was measured using a custom device. Analyses of variance with Bonferroni post hoc tests determined technique and grade differences, intraclass correlation coefficients the reliability between therapists, and linear regression the factors associated with forces. Results Therapists apply distinct manual forces for different techniques and grades ( P < .001). Variability between therapists is high, but intratherapist reliability is good (intraclass correlation coefficient [2,1] for different force parameters, 0.84-0.93). Mean peak forces increase from grades I to IV, ranging from 22 to 92 N for resultant forces. Greater vertical and caudad-cephalad forces are applied to C7 than C2 ( P < .01), with higher mediolateral forces during unilateral techniques ( P < .001). Male sex of the therapist or the mobilized subject is associated with higher forces, and C2 stiffness, thumb pain and postgraduate training with lower ( P < .05). Conclusions These results quantify cervical mobilization forces, which will inform future research aimed at improving its application and clinical effectiveness.

Isolated tuberculosis of C2 spinous process

Background context Isolated tuberculosis (TB) of posterior elements is extremely rare. Only few cases are reported in literature but none described isolated spinous process involvement in the absence of disease process in any other part of the body. Purpose The authors report a case of isolated tuberculous involvement of C2 spinous process, which to the best of our knowledge, is first such case report. Study design A case report of isolated C2 spinous process TB. Methods Sixteen-year-old girl presented with two-month history of slow growing, painless lump at the back of her neck without any other symptoms. X-ray showed erosion of C2 spinous process. MRI also suggested an abscess. Results Patient underwent incision and drainage of abscess and debridement of involved bone. Cultures and histopathology confirmed TB. Patient responded to antituberculous therapy. Conclusion Posterior element TB is a rare condition but in countries where TB is common, its possibility should always be considered. Isolated TB of parts of posterior elements can occur in absence of disease elsewhere.

Preservation of the Nuchal Ligament Plays an Important Role in Preventing Unfavorable Radiologic Changes After Laminoplasty

Prospective study. To examine whether preservation of the funicular section of the nuchal ligament attached to the C6 and C7 spinous processes could prevent unfavorable radiologic changes such as kyphotic deformity and destabilization at the C6/7 segment, and to investigate possible correlations between adverse radiologic changes and neurologic recovery or incidence of axial neck pain after laminoplasty in patients with cervical spondylotic myelopathy. Adverse radiologic changes after cervical laminoplasty have been reported to result from detachment of cervical extensor muscles. Subjects comprised 37 patients who underwent modified C3-6 laminoplasty. Our procedure preserves the funicular section of the nuchal ligament attached to the C6 and/or C7 spinous processes in addition to all muscles attached to the C2 and C7 spinous processes and the subaxial deep extensor muscles on the hinged side. The funicular section of the ligament attached only to the C7 spinous process was preserved in 18 patients (C7 group). This funicular section attaching both to the C7 and C6 spinous processes was preserved in 19 patients (C6+7 group). Radiologic and clinical data were prospectively collected. Postoperative loss of lordosis and destabilization at the C6/7 segment were significantly reduced in the C6+7 group compared with the C7 group. As of final follow-up, neurologic recovery was significantly poorer in the 3 patients with kyphosis than in the 34 patients with straight spinal alignment or lordosis. Frequencies of axial pain showed no significant differences between groups. This value did not vary with the differences in sagittal alignment. These results indicate that the preserved funicular section of the nuchal ligament attached both to the C6 and C7 spinous processes plays an important role in preventing undesirable radiologic changes after laminoplasty.

Effect of Preserving Paraspinal Muscles on Postoperative Axial Pain in the Selective Cervical Laminoplasty

A retrospective clinical study. To evaluate the effect of preservation of paraspinal muscles attached at the spinous process of C2 or C7 in selective laminoplasty on postoperative axial pain. Several methods of modified laminoplasty such as selective decompression and/or reconstruction of detached paraspinal muscles have been reported. It is still unclear, however, which posterior muscles need to be preserved to reduce postoperative problems. The study group consisted of 145 patients who underwent cervical laminoplasty. The level of decompression was decided based on preoperative cervical magnetic resonance imaging. The level of detachment of muscle from the spinous process was from 1 cranial to the decompression level and to the same level caudal to the level of decompression. Clinical outcome was evaluated based on improvement ratio of Japanese Orthopedic Association (JOA) score. In addition, the risk factors for postoperative axial pain were examined by multivariate logistic regression analysis. In 113 patients, C2 paraspinal muscles were detached, with elevation of the C3 lamina, and the improvement ratio of JOA score was 56.0%. In 32 patients, the muscles were preserved, without elevation of the C3 lamina, with corresponding ratio of 54.8%. In 112 patients, C7 paraspinal muscles were detached, with elevation of the C7 lamina, and in 33 patients the muscles were preserved; the improvement ratios of JOA score for these groups were 56.7% and 52.4%, respectively. There were no significant differences in clinical outcome among the groups. Older age (odds ratios: 0.17, 95% confidence intervals: 0.04-0.72) and preservation of muscles attached at the C2 spinous process (OR: 0.13, 95% CI: 0.02-0.98) decreased the risk of postoperative axial pain. Muscle-preserving selective laminoplasty yielded clinical outcomes equivalent to those of conventional C3-C7 laminoplasty in cervical compression my elopathy. Preservation of the muscles attached at C2 resulted in reduction of postoperative axial pain.

Surgical Anatomy of the Nuchal Muscles in the Posterior Cervicothoracic Junction

An anatomic study investigated the attachment of the nuchal muscles to the spinous process. To investigate the anatomic details of the attachment of the nuchal muscles to the spinous process, and which muscles are spared, and to what extent, when the C7 spinous process is preserved in the cervical laminoplasty. In previous studies, it was reported that the incidence of postoperative axial pain was lower in C3-C6 laminoplasty than in C3-C7 laminoplasty, emphasizing the effectiveness of the former procedure where discission of the nuchal muscles that are attached to the C7 spinous process is avoided. However, there have been no detailed anatomic studies of the attachment of the nuchal muscles to the spinous process at the cervicothoracic junction. The anatomy of the speculum rhomboideum of the trapezius, rhomboideus minor, rhomboideus major, serratus posterior superior, splenius capitis, and splenius cervicis to the spinous processes of the cervicothoracic junction were studied using 50 cadavers. The possibility of total discission of the speculum rhomboideum of the trapezius was 0% with C3-C6 laminoplasty and 18% with C3-C7 laminoplasty. More than 50% preservation of the speculum rhomboideum of the trapezius is possible in 72% in C3-C6 laminoplasty and 16% in C3-C7 laminoplasty. In C3-C7 laminoplasty, the possibility of partial preservation of the rhomboideus minor, serratus posterior superior, and splenius capitis at the spinous process was 0%, 66%, and 29%, respectively. The rhomboideus major in 16% and the splenius cervicis in 56% could be completely preserved without partial discission of the muscle attachment. On the other hand, in C3-C6 laminoplasty, the muscles that were spared without complete discission of the muscular attachment at the spinous process were the rhomboideus minor in 35%, the serratus posterior superior in 100% and the splenius capitis in 67%. The rhomboideus major in 76% and the splenius cervicis in 80% were completely spared without partial discission of the muscular attachment. The current study confirmed that C3-C6 laminoplasty in which the C7 spinous process is preserved reduces invasion of the nuchal muscles.

Limitation of activities of daily living accompanying reduced neck mobility after laminoplasty preserving or reattaching the semispinalis cervicis into axis

Although difficulties with neck mobility often interfere with patients' activities of daily living (ADL) after cervical laminoplasty, there was no detailed study on the relation between the limitations of ADL accompanying postoperative reduced neck mobility and the cervical posterior approach. The aim of this study was to compare retrospectively the frequency of limitations of ADL accompanying neck mobility after laminoplasty preserving the semispinalis cervicis inserted into the C2 spinous process with that after laminoplasty reattaching the muscle to C2. Forty-nine patients after C4-C7 laminoplasty with C3 laminectomy preserving the semispinalis cervicis inserted into C2 (Group A) and 24 patients after C3-C7 laminoplasty reattaching the muscle (Group B) were evaluated. The frequency of postoperative limitations of ADL accompanying each of three neck movements of extension, flexion and rotation were investigated. The postoperative O-C7 angles at extension and flexion was measured on lateral extension and flexion radiographs of the cervical spine, respectively. The postoperative cervical range of motion in rotation was measured in the cranial view using a digital camera. Frequency of limitations of ADL accompanying extension was lower (P = 0.037) in Group A (2%) than in Group B (17%). Frequency of limitations of ADL accompanying flexion was similar in Group A (8%) and Group B (4%). Frequency of limitations of ADL accompanying rotation was lower (P = 0.031) in Group A (12%) than in Group B (33%). Average O-C7 angle at extension was significantly larger (P = 0.002) in Group A (147 degrees ) than in Group B (136 degrees ). Average O-C7 angle at flexion was similar in Group A (93 degrees ) and Group B (91 degrees ). Average range of motion in rotation was significantly larger (P = 0.004) in Group A (110 degrees ) than in Group B (91 degrees ). This retrospective study suggested that the frequency of limitations of ADL accompanying neck extension or rotation was lower after laminoplasty preserving the semispinalis cervicis inserted into C2 than after laminoplasty reattaching the muscle.

Development and evaluation of thoracic kyphosis and lumbar lordosis during growth

The aim of this study was to establish ranges of angular variation in lordotic and kyphotic curves in normal male and female children and adolescents. We developed a pantograph to measure dorsal curves. It consisted of a tripod-supported vertical strut to which an articulated bar was fixed and which had an arm that was able to follow the dorsal surface while moving up and down. This arm was positioned over the C7 spinous process and followed spinous processes to L5 at constant speed. A laser beam was used to ensure the proper positioning of the pantograph and the subject. The motion was recorded using software so that the dorsal outline was represented on a computer screen, and lordotic and kyphotic curves were automatically measured. Before performing the population study, the pantograph was validated in 20 normal subjects by comparing the pantograph measurements with lateral spine radiographs. There were no statistically significant differences in the measurements. There were 718 subjects with no race selection, of whom 350 were males and 368 females ranging in age from 5 to 20 years and presenting normal weight and height. Individuals with generalized ligament laxity, trunk asymmetry, muscle retraction, or any orthopedic anomaly were excluded from the study. Data were analyzed according to age and gender. Student's t tests and regression analysis were performed. Kyphotic curves increased linearly from 25 degrees at 7 years of age to 38 degrees at 19 years of age (kyphotic angle = 25 degrees + 0.58 x age). Lordotic curves increased linearly from 22 degrees at 5 years of age to 32 degrees at 20 years of age (lordotic angle = 24 degrees + 0.51 x age). There were no differences between males and females. The pantograph that was developed for this study was successfully used to establish the normal ranges and progression of thoracic kyphosis and lumbar lordosis in the studied population. Both curves increased linearly with age, with no differences between males and females.

A Case of Vertebral Metastasis With Pathologic C2 Fracture

Objective This report discusses a patient with a pathologic fracture of the C2 vertebra secondary to osteolytic metastasis from squamous cell carcinoma of the lung. Clinical Features The patient was a 68-year-old man with a chief complaint of neck pain who was referred by his physician to a chiropractic office. The initial onset of neck pain began after a forceful sneeze that resulted in a sensation of “a twig snapping” in the neck. Radiographs revealed osteolytic destruction and pathologic fracture of the C2 spinous process. Intervention and Outcome The patient was referred back to his primary care physician, who then referred him to an oncologist, who immediately initiated a course of radiation therapy and pain medication. Palliative care by the chiropractor consisted of soft tissue massage of the cervical spine musculature to treat associated muscle spasms and pain. The patient responded well to gentle myofascial therapy. However, the osteolytic destruction of the C2 posterior elements progressed, resulting in an unstable subluxation of C2 and associated cord compression. The spine was stabilized with a rigid collar, but the metastatic destruction progressed, eventually resulting in quadriplegia and subsequent death from respiratory distress. Conclusion Patients with a history of cancer complaining of new onset of back or neck pain should be assumed to have vertebral metastasis until proven otherwise. Trivial trauma should be taken seriously in these cases and investigated with appropriate clinical, laboratory, and imaging examinations. Vertebral malignancies may be a contraindication to spinal manipulation; however, the chiropractic physician plays a significant role in early detection and diagnosis.

Importance of preserving the C7 spinous process and attached nuchal ligament in French-door laminoplasty to reduce postoperative axial symptoms

A comparative clinical trial was conducted to clarify the importance of preserving the C7 spinous process and attached nuchal ligament for the reduction of the axial symptoms after French-door laminoplasty in cervical spondylotic myelopathy patients. Forty-one cervical spondylotic myelopathy patients were enrolled. French-door laminoplasty from C3 to C7 in 22 patients (group 1), and from C3 to C6 in 19 patients (group 2) was performed. The whole structure of the C7 spinous process and the attached nuchal ligament were preserved in group 2. The pre- and post-operative evaluation regarding severity of clinical symptoms was assessed using the Japanese Orthopaedic Association (JOA) score. Pre-operative and subjective outcome regarding axial symptoms were also assessed using a visual analog pain scale questionnaire (VAS: 10-0, where a higher score indicates greater pain) at 1- and 2-year follow-up. Non-parametric testing (Mann-Whitney's U test) was used to establish differences between the two groups for categorical data (P < 0.05). There was no significant difference between the two groups in pre- and post-operative JOA score. The mean VAS was 5.6 +/- 1.4 in group 1, 5.4 +/- 1.7 in group 2 pre-operatively, and 6.4 +/- 1.7 in group 1 and 2.4 +/- 1.9 in group 2 at 1-year follow-up. The mean VAS score at 2-year follow-up exhibited 6.2 +/- 1.9 in Group 1, 2.3 +/- 1.8 in group 2. There was no significant difference in VAS between the two groups before surgery (P = 0.506), but significant differences were noticed at 1-year and 2-year follow-up (P < 0.05), indicating the presence of significantly fewer post-operative axial symptoms in group 2. Laminoplasty of the entire C7 structure is not necessary to obtain satisfactory recovery based on JOA score. Preservation of the C7 spinous process and the attached nuchal ligamentous structures is important to reduce post-laminoplasty axial symptoms.

The Middle Interscalene Block: Cadaver Study and Clinical Assessment

A variety of brachial plexus block techniques via the interscalene approach have been proposed. We describe here a new middle interscalene perivascular approach to the brachial plexus. To verify its effectiveness, we studied 719 patients scheduled for shoulder arthroscopy. Furthermore, to verify the accuracy of the proposed bony landmarks to use in the case of inability to palpate the subclavian artery pulse, we simulated the block on 10 cadavers. The aim of our technique is to cannulate the neurovascular bundle by inserting a 35-mm needle lateral to the subclavian arterial pulse near the midpoint of the upper edge of the clavicle in a horizontal or slightly cephalad direction while pointing toward the seventh cervical vertebra. If the pulse of the subclavian artery is not palpable, we localize the direction of the needle with reference to 3 bony landmarks (the middle point of the clavicle, the spinous process of C7, and the sternoclavicular joint). By connecting these 3 landmarks, we obtain an angle whose apex lies at the midpoint of the clavicle and its bisecting line points to the plexus. The needle is introduced in the transverse plane of C7. The block was performed successfully in 692 of 719 cases (96.2%). Horner's syndrome occurred in 93.5% of the cases, arterial puncture with hematoma occurred in <1%, phrenic nerve block without respiratory impairment in 60%, with transient respiratory failure in <1%, and laryngeal nerve block in <1%. The incidence of severe complications or permanent injuries was zero (upper limit 95% confidence interval = 0.4% or 1:250 patients). The technique performed on cadavers showed that the previously mentioned bony landmarks were reliable reference points in reaching the brachial plexus. Our technique via a middle interscalene approach is easy to perform and provides a high success rate. Even in the absence of a subclavian artery pulse, the easily recognizable bony landmarks reliably guide us in the insertion of the needle. Furthermore, this technique appears to avoid complications that are theoretically possible in other supraclavicular perivascular approaches (pneumothorax) and paravertebral approaches (injection into the vertebral artery and subarachnoidal injection). However, further comparative studies will be required to assess the clinical relevance of the block.

A Case Report of an Unstable Cervical Spine Fracture: Parallels to the Thoracolumbar Chance Fracture

Objective To discuss the case of a 40-year-old woman who had a cervical spine fracture similar in appearance to a Chance fracture and to discuss its radiographic appearance. Clinical Features A 40-year-old woman sought chiropractic care for neck pain and weakness in both arms after a motor vehicle accident. Neck flexion worsened the weakness in her upper extremities, her radiating neck pain, and upper extremity pain. A transverse fracture through the spinous process of C6 and narrowed C6 disk space was noted on plain film radiographs. Magnetic resonance imaging findings were consistent with a large midline extruded disk herniation at the C6-7 level with marked extrinsic compression on the cervical cord in addition to the fracture. These findings were similar to a lumbar spine Chance fracture. Intervention and Outcome The patient was referred for surgical consultation, and discectomy with fusion of C6-7 was performed. After the surgery, the upper extremity pain and weakness subsided. Postsurgical care included chiropractic adjustments with a handheld spring-loaded adjusting instrument and physiotherapy. Conclusion The radiographic features of an unusual cervical spine fracture with the characteristics of a Chance-type fracture are discussed.