Cervical Intervertebral Disc Herniation Research Articles

Clinical and imaging findings in dogs with nerve root signature associated with cervical intervertebral disc herniation.

Intervertebral disc herniation (IVDH) is the most common spinal cord disease in dogs. Little information is available regarding the clinical presentation of nerve root signature (NRS) associated with cervical IVDH. To detail the clinical and magnetic resonance imaging (MRI) findings in dogs with NRS associated with cervical IVDH. Forty-seven client-owned dogs presenting with thoracic limb NRS and MRI confirmed IVDH. Medical records from 2010 to 2020 were retrospectively reviewed for dogs that met inclusion criteria. Imaging studies were evaluated by 2 individuals to characterize location and severity of neural tissue compression. Chondrodystrophoid dogs comprised the majority of the study cohort, with dachshund the most common breed (n = 10). Three-quarters of dogs were ≥7 years of age. Interobserver agreement was moderate or good for all of the imaging variables evaluated. The C6-C7 intervertebral disc space was significantly overrepresented (P = .01), comprising 32% (15/47) of the affected discs. However, 42% (20/47) of cases involved C2-C3 though C4-C5 disc sites. Disc material was more frequently located laterally compared to medially within the vertebral canal (P = .0005), and to be associated with compression of the nerve root at the level of the intervertebral foramen (P = .012). NRS is most commonly associated with lateralized or foraminal cervical disc herniations. It is most prevalent with C6-C7 intervertebral disc involvement, suggesting that there might be unique anatomic factors that contribute to development of NRS at this site, but can be a clinical manifestation of IVDH occurring anywhere along the cervical spine.

Examination of annulus fibrosus and nucleus pulposus in cervical and lumbar intervertebral disc herniation patients by scanning acoustic microscopy, scanning electron microscopy and energy dispersive spectroscopy.

Intervertebral disc herniation (IVDH) is observed in humans as a result of the alteration of annulus fibrous (AF) and nucleus pulposus (NP) tissue compositions in intervertebral discs. In this study, we studied the feasibility of scanning acoustic microscopy (SAM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) in characterizing the herniated segments of AF and NP tissues from male and female patients. SAM determined the acoustic property variations in AF and NP tissues by calculating the acoustic impedance values of samples of 15 patients. SEM obtained higher resolution images and EDS made elemental analysis of the specimen. Consequently, we suggest that these techniques have the potential to be combined for the investigation and removal of the disrupted AF and NP tissues with micrometer resolution in clinics.

Video telescope operating monitor-assisted surgery is equivalent to conventional surgery in treatment of cervical intervertebral disc herniation in dogs.

To compare the use of the video telescope operating monitor (VITOM) and use of a conventional unassisted surgical method for treatment of cervical intervertebral disc herniation in dogs. 39 dogs with cervical intervertebral disc disease. Prospective study. Dogs were prospectively nonrandomly assigned to either the VITOM (n = 19) or conventional surgery (20) group depending on VITOM system availability. Signalment and preoperative neurologic status were recorded for all dogs. Preoperative and postoperative CT myelography was performed to compare intervertebral space location, spinal cord dimensions at the decompression level, ventral slot dimensions, and residual disc material. Surgical complications and postoperative neurologic outcomes were recorded. Data were compared between the 2 groups using fixed-effects or mixed-effects models to consider double reading of CT myelography images. No significant differences were noted between the 2 groups regarding the decompression ratio (P = .85), vertebral length body ratio (P = .13), ventral slot width ratio (P = .39), residual disc material (P = .30), and sinus bleeding (P = .12). No significant differences were found between the 2 groups regarding postoperative neurologic grade (P = .17). VITOM-assisted ventral slot decompression is equivalent to conventional surgery in treatment of cervical intervertebral disc herniation in dogs. The use of VITOM remains a good alternative to the conventional surgical method.

Vertebral fixation does not affect recovery or recurrence of cervical intervertebral disc herniation in small dogs (< 15 kg).

To compare the prognosis of small dogs with cervical intervertebral disc herniation (C-IVDH) when treated with ventral slot decompression (VSD) alone or with concomitant vertebral fixation (VF). Small dogs (n = 303) weighing < 15 kg diagnosed with C-IVDH and treated with VSD. We recorded signalment, cervical myelopathy grade, surgical site, use of VF, degree of adjacent disc degeneration, recovery, recurrence, recurrence site, and postoperative course, including the time elapsed from recovery to recurrence. We examined factors associated with recovery and recurrence during the 30-month postoperative period using multivariate logistic regression analysis. VF did not affect recovery (P = .79). However, nonchondrodystrophic breeds had poorer recovery (OR, 5.89; P = .023) than chondrodystrophic breeds, and a higher preoperative cervical myelopathy grade (grade 3 or 4) was associated with poorer recovery (OR, 7.09 or 3.46, respectively; P = .019 or .042, respectively), compared with grade 1. VF did not affect recurrence (P = .79); however, increasing age was associated with recurrence (OR, 1.79; P = .001). In small dogs weighing < 15 kg, there was no difference in postoperative recovery and recurrence rates after VSD with or without concomitant VF. Therefore, in small dogs with C-IVDH, even if the slot volume is increased to remove sufficient disc material during VSD, a good prognosis can be achieved with or without VF.

Cervical spine and muscle adaptation after spaceflight and relationship to herniation risk: protocol from ‘Cervical in Space’ trial

BackgroundAstronauts have a higher risk of cervical intervertebral disc herniation. Several mechanisms have been attributed as causative factors for this increased risk. However, most of the previous studies have examined potential causal factors for lumbar intervertebral disc herniation only. Hence, we aim to conduct a study to identify the various changes in the cervical spine that lead to an increased risk of cervical disc herniation after spaceflight.MethodsA cohort study with astronauts will be conducted. The data collection will involve four main components: a) Magnetic resonance imaging (MRI); b) cervical 3D kinematics; c) an Integrated Protocol consisting of maximal and submaximal voluntary contractions of the neck muscles, endurance testing of the neck muscles, neck muscle fatigue testing and questionnaires; and d) dual energy X-ray absorptiometry (DXA) examination. Measurements will be conducted at several time points before and after astronauts visit the International Space Station. The main outcomes of interest are adaptations in the cervical discs, muscles and bones.DiscussionAstronauts are at higher risk of cervical disc herniation, but contributing factors remain unclear. The results of this study will inform future preventive measures for astronauts and will also contribute to the understanding of intervertebral disc herniation risk in the cervical spine for people on Earth. In addition, we anticipate deeper insight into the aetiology of neck pain with this research project.Trial registrationGerman Clinical Trials Register, DRKS00026777. Registered on 08 October 2021.

Dysphagia as a Postoperative Complication of Anterior Cervical Discectomy and Fusion.

Anterior cervical discectomy and fusion (ACDF), despite its possible complications, remains the gold standard for the surgical treatment of patients with radiculopathy and/or myelopathy caused by cervical intervertebral disc herniation or spondylosis. Despite its high rate of incidence, postoperative dysphagia following ACDF is still poorly understood; its pathogenesis remains relatively unknown, and its risk factors are still a subject of debate.The aim of this study is to review the incidence, pathogenesis, diagnosis, and methods of prevention of dysphagia in ACDF patients. To this end, a literature review was conducted based on the PubMed internet database. Article titles were searched by using the following keywords: “dysphagia” and “anterior cervical discectomy and fusion” or “ACDF”. The search was limited to prospective clinical studies evaluating dysphagia after ACDF surgery. Studies published in non-English languages, retrospective studies, cadaveric studies, reviews, case reports, study protocols, and commentary studies were excluded.Initially, 335 studies were identified after a primary search. After the application of the exclusion criteria, 73 studies remained for the final analysis. This literature review focused on identifying the rate of dysphagia and the various risk factors leading to this complication by comparing and evaluating the current literature with a wide spectrum of heterogeneity concerning patients, surgeons, and surgical techniques. A mean dysphagia rate of 19.4% (95% CI: 9.6%-29.1%) based on the findings of the included studies correlating dysphagia directly with ACDF procedures was calculated. Various established risk factors leading to dysphagia include the female sex, smoking, the surgical approach, rhBMP-2 use, and multilevel surgery, while zero-profile devices seem to reduce dysphagia risk. The diagnosis is based on clinical and radiological findings, especially prevertebral soft-tissue swelling. However, videofluoroscopic and endoscopic studies have been recently used for the evaluation of dysphagia. The role of local administration of steroids in the prevention of dysphagia has not yet been clarified. This review underscores the prevailing rudimentary understanding of the problem of dysphagia after ACDF procedures and highlights the need for more sensitive, factor-specific studies for understanding the impact of various risk factors on the incidence rate of dysphagia.

Ozone disc nucleolysis in cervical intervertebral disc herniation: A nonrandomized prospective analysis in 246 patients

ABSTRACTBackground:Inherent complications associated with surgery and limited success of percutaneous minimally invasive procedures make researches wanting for an ideal treatment for cervical disc herniation.Objective:We prospectively study the role of ozone disc nucleolysis in cervical intervertebral disc herniation.Patients and Methods:From January 2008 to December 2020, we prospectively study 246 consecutive patients of cervical disc herniation treated by a single session of intradiscal injection of ozone–oxygen mixture (ozone disc nucleolysis). There were 55% of females and 45% of males. Age ranged from 28 to 68 years with a mean of 47. The outcome was measured on visual analog scale (VAS) scale and neck disability index (NDI) along with Mcnab method.Results:The mean baseline VAS score was 7.87 which became 3.09 at 1 month, 1.42 at 3 months, 1.40 at 6 months, and 1.35 at 1 year. The mean NDI was 36.27 at baseline which improved to 9.24 at 1 month, 6.25 at 3 months, 6.20 at 6 months, and 6.22 at 1 year. This was found to be significant with P < 0.05. Modified McNab criterion showed excellent recovery in 138 (56.10%), good recovery in 50 (20.32%), and fair recovery in 22 (8.94%), resulting in a successful rate of 85.36%. Mediocre recovery was seen in the remaining 36 patients amounting to a 14.64% failure rate.Conclusion:This study showed that ozone disc nucleolysis significantly reduces the pain related to cervical disc herniation along with a significant reduction in disability.

Midshaft clavicle fracture with hypertrophy of the fractured end

Abstract Introduction: Midshaft clavicle fractures are common fractures, but clavicle fractures with hypertrophy of the fractured end are rare. To the best of our knowledge, there are no reports describing this peculiar form of fracture. Patient concerns: A 68-year-old woman was admitted to the orthopedic department for treatment of left shoulder joint swelling and pain with limited mobility for 1 day duration She had a history of falls and an old left distal radius fracture, but no history of left shoulder joint swelling, pain, and limited mobility. Diagnosis: 1. Midshaft fracture of the left clavicle 2. Motor neuron injury 3. Multilevel cervical intervertebral disc herniation. 4. Brain atrophy 5. Old left distal radius fracture. Interventions: Surgical treatment was performed after detailed preoperative evaluation. During surgery, the clavicle fracture was anatomically reduced under direct vision (unusually, the fracture end was displaced during intraoperative fluoroscopy). After fracture reduction, one eight-hole locking plate was fixed with three locking screws at each end of the fracture. After the surgery, the patient was instructed to perform rehabilitation training. Outcomes: The sutures were removed on the 12th postoperative day, and the incision wound healing was good. Follow-up at one month after surgery revealed no swelling or pain at the left clavicle fracture site and both active and passive ranges of motion of the left shoulder joint were good. Conclusion: For clavicle fractures with hypertrophy of the fractured ends in the elderly, after excluding pathological fractures caused by tumors, satisfactory results can be obtained as long as strong internal fixation is achieved. In the midshaft clavicle fracture with hypertrophy of the fractured end, whether to achieve the reduction criteria under direct vision or intraoperative fluoroscopy imaging should be determined on the basis of the patient's actual condition. Motor neuron injury may promote the healing of clavicle fractures due to restricted motor function that promotes fracture healing.

脱出した椎間板物質によって内椎骨静脈叢が背外側に変位した頸部椎間板ヘルニアの犬の1例

脱出した椎間板物質によって内椎骨静脈叢が背外側に変位した頸部椎間板ヘルニアの犬の1例

Non-ambulatory dogs with cervical intervertebral disc herniation: single versus multiple ventral slot decompression.

To evaluate the proportion of non-ambulatory dogs with cervical intervertebral disc herniation (IVDH) in a private clinic and to compare signalment and outcome between those that underwent single or multiple ventral slot decompression (VSD). Retrospective cohort study. After screening 43,378 medical records (January 2010-September 2016), those of 185 dogs with non-ambulatory tetraparesis or tetraplegia along with cervical IVDH that had undergone single (123) or multiple (62) VSD were included in this study. Data on signalment, preoperative neurological status, location of affected intervertebral disc(s), time to ambulation and short-term outcome were compared between single and multiple VSD groups. The proportion of non-ambulatory dogs with IVDH was 35.3%. The prevalence of non-ambulation was higher in male dogs (0.56%) than in female dogs (0.26%; P < 0.001) and in neutered dogs than in unneutered dogs (0.51% and 0.27%, respectively, P < 0.001). After surgery, 96.2% of the dogs reached ambulatory status. Dogs with multiple IVDH were older than those with single IVDH. Sex, neutering status or size did not affect the outcome or ambulation status postsurgery. The Pekingese was the most commonly affected breed in both groups. There was no difference in the time to reach ambulation and the presence of neurological deficits after surgery between dogs that underwent single and multiple VSD. In this cohort, dogs undergoing multiple VSD had a good postoperative outcome, and their short-term functional recovery was equal to that of dogs undergoing single ventral slot compression.

Use of an Internal Retractor for Percutaneous Full-Endoscopic Resection in Cervical Intervertebral Disc Herniation with a Posterior Approach.

Study DesignA preliminary case series study.PurposeFor the safety of performing a posterior percutaneous full-endoscopic cervical discectomy.Overview of LiteratureBecause of the lack of space for inserting an outer sheath above the intervertebral disc in the spinal canal, grasping the herniated disc with forceps while retracting the nerves with the forceps itself was required. This procedure produces the risk of inadvertently injuring nerves because of inadequate visualization of the hernia and inadequate protection of the nerve.MethodsOur new internal retractor can be inserted into the working channel of a percutaneous full-endoscope, enabling the insertion of a second tool. After partial foraminotomy, the internal retractor and forceps were manipulated to reliably retract the nerve root. Finally, the herniated disc was resected under an endoscopic view.ResultsAll six cases had a good postoperative course, and postoperative neuropathy was not observed.ConclusionsThis internal retractor allows for the secure resection herniated cervical intervertebral discs.

A retrospective study of canine cervical disk herniation and the beneficial effects of rehabilitation therapy after ventral slot decompression

The objective of this study was to evaluate the clinical outcome of ventral slot decompression and rehabilitation therapy in dogs with cervical intervertebral disc herniation (IVDH). Surgical decompression was performed in dogs with IVDH using the ventral slot procedure. After surgery, physiotherapeutic rehabilitation consisted of a combination of electrotherapy, infrared therapy and mechanical massage; treadmill exercise was started when the animal could stand up. A total of 58 dogs were selected from the hospital and included in two groups: rehabilitated group (RG, n = 34) and non-rehabilitated group (NRG, n = 24). Dogs of each group were subdivided into five groups based on a pre-operative clinical grading system. Grade 1 designated spinal pain only, grade 2 designated ambulatory paraparesis, grade 3 designated non-ambulatory paraparesis, grade 4 designated paraplegia with deep-pain perception intact and grade 5 designated paraplegia without deep-pain perception. Post-operative changes of both groups were evaluated and compared, including time until unassisted standing and walking after surgery and the success rate. Overall, 79.41% (27/34) of dogs had a successful neurologic outcome in the RG group, which was significantly (P &amp;lt; 0.05) higher than the NRG group 62.50% (15/24). Interestingly, the success rate differed when the preoperative grading system was considered. The success rates of grades 1, 2, 3, 4 and 5 were 100% (9/9), 100% (7/7), 75% (3/4), 53.85% (7/13) and 100% (1/1), respectively, in the rehabilitated groups, whereas in the non-rehabilitated groups success rates were 100% (5/5), 83.33% (5/6), 60.00% (3/5), 28.57% (2/7) and 0% (0/1), respectively. The differences in success rates between the two groups according to grading were 0, 16.67, 15, 25.57 and 100%, respectively. The proposed rehabilitation therapy after surgical decompression of cervical IVDH can improve the success rate when the preoperative pathological condition is severe.

Sternoclavicular joint arthropathy mimicking radiculopathy in a patient with concurrent C4-5 disc herniation

BackgroundPatients with sternoclavicular joint arthropathy, which can result from septic arthritis, often present with localized sternoclavicular pain as well as shoulder pain. Such pain may be similar to the presenting symptoms of cervical intervertebral disc herniation. Clinical presentationA 47-year-old female presented with 1 month of significant pain in the neck as well as right anterior chest and deltoid. The patient was found to have reduced strength in the right deltoid muscle on physical examination. MRI revealed a C4-C5 herniated nucleus pulposus. The patient underwent successful C4-C5 anterior cervical discectomy, but subsequently developed painful swelling in the region of the right sternoclavicular joint with limited motor strength in the right shoulder and arm. A needle biopsy of the mass yielded negative results, but her erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) numbers did respond to antibiotics, consistent with infection of the sternoclavicular joint. A follow-up CT scan (6.5 months postoperatively) revealed apparent resolution right sternoclavicular joint arthropathy, thought the patient continued to experience pain. 15 months postoperatively, the patient was prescribed methotrexate due to persistent pain and mild weakness arising from a possible rheumatologic inflammation. 19 months postoperatively, the patient had full strength of the right shoulder and arm and visible decrease in swelling at the sternoclavicular joint. More than three years postoperatively, the patient was diagnosed with multiple myeloma, which was appropriately treated. At follow-up four years postoperatively, the patient had an MRI showing new C6-C7 herniated nucleus pulposus, but no longer had any right shoulder or chest pain or associated weakness. ConclusionThis case demonstrates that sternoclavicular joint arthropathy results in symptoms that can mimic the presenting symptoms of shoulder or cervical spine pathology, such as shoulder and neck pain, necessitating careful diagnosis and management.

Chemonucleolysis with chondroitin sulfate ABC endolyase as a novel minimally invasive treatment for patients with lumbar intervertebral disc herniation.

Chemonucleolysis is a minimally invasive treatment for cervical and lumbar intervertebral disc herniation (IDH). While this procedure has existed for more than 50 years, it has yet to become an established practice. The main reason for this is the low specificity of enzymes targeting nucleus pulposus (NP). Although two enzymes (chymopapain and collagenase) have been used in clinical settings, severe adverse events have discouraged widespread use. The recently introduced enzyme Proteus vulgaris chondroitin sulfate ABC endolyase may allow a new era of chemonucleolysis because of its high specificity for NP.

Posterior percutaneous endoscopic cervical discectomy through lamina–hole approach for cervical intervertebral disc herniation

Background: The optimal PECD surgical approach for cervical intervertebral disc herniation (CIVDH) remains controversial. The conventional posterior K-hole approach for PECD leads to damage of facet joint.Objectives: This article is to first describe a novel posterior lamina–hole approach of percutaneous endoscopic cervical discectomy (PECD) for CIVDH. The objective of this study is to evaluate the feasibility and short-term clinical effect of this approach.Methods: Single-center retrospective observational study of all patients managed with posterior percutaneous endoscopic cervical discectomy (PPECD) using the lamina–hole approach for symptomatic single-level CIVDH between January 2015 and January 2016. The clinical outcomes were evaluated with the visual analog scale, modified MacNab criteria and radiographical results.Results: Twelve patients (seven women, five men) were enrolled in the study. Positive clinical response for pain relief was achieved in these patients receiving PPECD through lamina–hole approach for CIVDH. Postoperative MRI showed complete removal of the disc material in all the patients, no failure due to residual fragment was observed.Conclusion: As an alternative surgical approach of PPECD, PPECD through lamina–hole approach is a novel access for CIVDH and may be considered a valid and safe therapeutic option for CIVDH. The advantages of this approach are not only providing a valid and secure access to herniated cervical intervertebral fragment but also avoiding the iatrogenic damage to the facet joint and relevant functional spinal unit (FSU). Theoretically, the potential of secondary degeneration of FSU is low.

A Novel Posterior Trench Approach Involving Percutaneous Endoscopic Cervical Discectomy for Central Cervical Intervertebral Disc Herniation.

This report describes a novel posterior trench approach involving percutaneous endoscopic cervical discectomy (PECD) for central cervical intervertebral disc herniation (CIVDH) and an evaluation of the feasibility, safety, and short-term clinical effect of this approach. Central CIVDH is considered the contraindication for posterior PECD. A single-center retrospective observational study was performed with 30 patients managed with posterior PECD using the trench approach for symptomatic single-level central CIVDH. Primary outcomes included the measures of bodily pain and physical function based on the SF-36 and modified MacNab criteria. Radiographical follow-up included the static and dynamic cervical plain radiographs, computed tomographic scans, and magnetic resonance images. A positive clinical response for symptom relief was achieved in all patients. The postoperative MRI showed total removal of the herniated disc. As a supplement to the described surgical techniques of PECD, this trench approach provides novel access for the treatment of CIVDH, especially for the central type. The advantages of this technique include the provision of access to decompress the ventral region of the thecal sac and the ability to avoid damage to the facet joint. The steep learning curve might be a major disadvantage, and the sample volume is a limitation of the study; the effectiveness and reliability of the trench approach should be further verified in a comparative cohort study with a large volume of patients.

Anterior Transcorporeal Approach to Percutaneous Endoscopic Cervical Diskectomy for Single-Level Cervical Intervertebral Disk Herniation: Case Series with 2-Year Follow-Up

To examine the effects of anterior transcorporeal percutaneous endoscopic cervical diskectomy (ATPECD) for the treatment of single-level cervical intervertebral disk herniation (CIDH) with a focus on its safety, feasibility, clinical efficacy, and specific possible complications. A series of 35 patients with symptomatic single-level CIDH were enrolled to be treated with ATPECD. Neck and arm pain was measured using the visual analog scale. Quality of life was measured using the bodily pain and physical function on the SF-36. The average disk height and vertical vertebral body height were recorded. Bone healing was evaluated on the basis of postoperative computed tomography. Successful removal of the herniated disk was confirmed in all 35 cases. At 2 years, the patients showed a significant treatment effect in the visual analog scale and body pain and physical function portions of the SF-36 (1.14 ± 0.60 vs. 7.62 ± 0.61, 63.92 ± 6.74 vs. 32.55 ± 6.80, and 82.14 ± 6.22 vs. 34.43 ± 4.50, respectively, P < 0.01). Mean preoperative disk height was 6.79 ± 0.37 mm, which decreased to 6.34 ± 0.46 mm 2 years post operation (6.6% decrease). Preoperative surgical vertebral body height also decreased from preoperation (15.79 ± 0.52 mm) to 2 years post operation (15.12 ± 0.38 mm) (4.2% decrease). Three surgery-related complications were observed (8.6%). Preliminary clinical experience with ATPECD shows that it is safe, effective, feasible, and minimally invasive. Although it has some disadvantages, such as the need for repeated fluoroscopy, some minor complications, and nonsymptomatic disk height decreases, ATPECD can supplement minimally invasive surgeries in selected cases of CIDH.

The indication selection of posterior percutaneous endoscopic cervical discectomy for cervical intervertebral disc herniation

Objective To reduce the risk of cervical spinal cord injury, the most medial point of the cervical intervertebral disc that the posterior percutaneous endoscopic sheath could reach was evaluated. And that could help to determine the indication of posterior percutaneous endoscopic cervical discectomy for cervical intervertebral disc herniation. Methods Cervical MRI images for 50 randomly selected patients, 21 males and 29 females with ages from 20 to 60(average 33.5±10.03 years), were analysed. All 50 patients underwent MRI examination at our institution between January 2014 and December 2017. As 50% of the zygapophyseal joint was preserved, on the cross-section T2-weighted MRI images, when the sheath just touched the spinal cord, the intersection point of the medial wall of sheath and cervical spinal cord (Point L) was the most medial point of the posterior percutaneous endoscopy could get. The distance between Point L and the line through and tangent to the most lateral point of cervical disc border was the length of the line section DL. The distance between the middle sagittal line of the cervical disc and the line through and tangent to the most lateral point of cervical disc border was the length of the line section D. DL/D was the most medial distance ratio of the posterior percutaneous endoscopic cervical discectomy when 50% of the lateral zygapophyseal joint was preserved. In the same way, D’L/D was the most medial distance ratio of the posterior percutaneous endoscopic cervical discectomy when 75% of the lateral zygapophyseal joint was preserved. Results When 50% of the lateral zygapophyseal joint was preserved, the upper limit of 95% confidence intervals of the most medial distance ratio that the posterior percutaneous endoscopy could get were 78%, 76%, 81%, 93% in C3, 4, C4, 5, C5, 6, C6, 7 respectively. This meant that the most medial distance the posterior percutaneous endoscopy could get were the 78%, 76%, 81%, 0.93% of the length of the line section D in C3, 4, C4, 5, C5, 6, C6, 7 respectively. The most medial distance the posterior percutaneous endoscopy could get in C5, 6 or C6, 7 was longer than that in C3, 4, C4, 5. Conclusion When 50% of the lateral zygapophyseal joint was preserved, the upper limit of the most medial distance ratio that the posterior percutaneous endoscopy should get were 78%, 76%, 81%, 93% in C3, 4, C4, 5, C5, 6, C6, 7 respectively. This meant that the most medial distance the posterior percutaneous endoscopy could get were the 78%, 76%, 81%, 93% of the length of line section D in C3, 4, C4, 5, C5, 6, C6, 7 respectively. If the resected disc was beyond this range, the cervical spinal cord should be in the risk of being injured. Key words: Cervical vertebrae; Intervertebral disc displacement; Endoscopy; Surgical procedures, minimally invasive

Usage of Bone Wax to Facilitate Percutaneous Endoscopic Cervical Discectomy Via Anterior Transcorporeal Approach for Cervical Intervertebral Disc Herniation

Currently, anterior transdiscal access and posterior interlaminar approach are the main approaches for percutaneous endoscopic cervical discectomy (PECD). To overcome access shortcomings, we previously described a novel anterior endoscopic transcorporeal approach on a migrated cervical disc. We innovatively introduced bone wax into endoscopic surgery to aid hemostasis and facilitate the process of drilling an intracorporeal tunnel. Five patients with cervical intervertebral disc herniation (CIDH) were treated by PECD via the anterior transcorporeal approach. During the operation, we marked the punctured tunnel with bone wax containing indigo carmine as a guide and smeared bone wax on the endoscopic burr to aid hemostasis. A satisfactory clinical outcome was observed in all 5 patients postoperatively; pain and neurologic condition were dramatically improved. Surgery-related complications, such as esophageal injury, vascular rupture, hematoma, intervertebral disc infection, or postoperative headache, were not encountered. A computed tomography scan was used to observe the process of bone healing. At 3-month postoperative follow-up, the bone defect within the drilling tunnel had partially shrank and was completely healed at 6 months postoperatively. The anterior endoscopic transcorporeal approach for PECD is a novel, valuable alternative for the treatment of CIDH. Bone wax could indeed facilitate the operation by guiding the drilling process and instantly controlling the bleeding without obvious interference with bone healing. Long-term follow-up is warranted in further clinical studies.

Effect of Cervical Spinal Decompression on the Cervical Muscle Tone and Disc Height in Patients with Cervical Intervertebral Disc Herniation

The purpose of this study was to investigate the effect of traction and decompression therapies on the cervical muscle tone and disc height. The decompression group (n=16) received decompression therapy and Mckenzie exercises once a day and four times a week respectively, for three weeks. The traction group (n=15) also received traction therapy and Mckenzie exercises for the same period. Muscle tone was measured with a myotonometer, and the disk height was measured using magnetic resonance imaging (MRI), before the interventions. Three weeks later, we investigated the therapeutic effect by repeating these measurements. The difference in disk height between the two groups was not significant. There was a significant difference in the disk herniation index (p<.05). A significant difference was found only in the upper trapezius muscle after comparison of muscle tone and stiffness between the groups (p<.05). Findings from this study suggest that the decompression therapy is a more effective intervention for patients with cervical intervertebral disc herniation.