Anterior Cervical Approach Research Articles

A New Porcine Animal Model of Cervical Disc Degeneration

Introduction Previous in vivo animal model for disc degeneration was predominantly smaller animals. But such small discs were inappropriate to investigate the cell transplantation therapy highlighted recently. A porcine disc degeneration model in lumbar spine was introduced; however, the lumbar spine was not influenced by the gravity. Hence, the authors performed porcine animal model of disc degeneration in cervical spine. Materials and Methods Three domestic minipigs (aged, 5 months; weight, 40-50 kg) were used. After anesthesia, right transverse 5 cm-sized incision was made over the three fingers above the clavicle on the anterior neck. Similar to a standard anterior cervical approach of Smith-Robinson method, anatomic dissection was performed to expose anterior surface of the cervical spine. The partial nucleotomy by a Jamshidi bone marrow biopsy needle was performed in one intervertebral disc, and the other disc spaces served as control. Radiologic study using lateral plain radiograph (X-ray) and magnetic resonance image (MRI) was evaluated at preoperation and postoperative 4 and 8 weeks. Results Two of three minipigs were confirmed disc degeneration at C4-5 and C6-7, respectively. The disc height was reduced by 20% at nucleotomy level. And these discs with previous Pfirrmann grade I were changed to grade IV degeneration at postoperative 4 and 8 weeks. The other disc spaces were maintained previous disc height and Pfirrmann grade I condition. Conclusion This was a pilot study to introduce a new disc degeneration model with relatively large animal at cervical spine. The authors will conduct a further experiment to confirm the cervical disc degeneration and plan the cell therapy for treatment of disc degeneration. Disclosure of Interest None declared

A case series on the technical use of three-dimensional image guidance in subaxial anterior cervical surgery

Three dimensional (3D) image guidance has been used to improve the safety of complex spine surgeries, but its use has been limited in anterior cervical spine approaches. Twenty-two patients underwent complex anterior cervical spine surgeries in which 3D image guidance provided intraoperative assistance with the dissection, decompression and implant placement. One of two paired systems, the BrainLAB (BrainLAB, Westchester, Illinois) system, or Stealth (Medtronic Inc., Littleton, Massachusetts) system was used for 3D image guidance in this study. Image guidance was able to reliably locate pertinent anatomical structures in complex anterior cervical spine surgery involving re-exploration, dissection around vertebral arteries or deformity correction. No complications occurred, and no patients required a revision anterior surgery. This technical note describes the setup and technique for the use of cone beam computed tomography (cbCT)-based, 3D image guidance in subaxial anterior cervical surgery. The authors have found this technique to be a useful adjunct in revision anterior cervical procedures, as well as anterior cervical procedures involving corpectomy or tumor removal.

Surgical Planning and Neurological Outcome After Anterior Approach to Remove a Disc Herniation at the C7–T1 Level in 19 Patients

Retrospective cohort study. The purpose of this study was to report the neurological presentation, outcome and surgical planning in a series of patients with a symptomatic single-level C7-T1 disc herniation who underwent anterior surgical discectomy and fusion. Disc herniations at C7-T1 are uncommon, and there are few large series in the literature describing anterior treatment of such herniations. We performed a retrospective study of patients who underwent surgery for a C7-T1 disc herniation and reviewed the medical records, operative reports, and imaging studies. The surgeons' view line was drawn and its relation to the manubrium and the great vessels was determined on T1 sagittal magnetic resonance imaging. The location of the herniated disc in the spinal canal was determined using a T2 axial magnetic resonance imaging and classified as central, foraminal, and central/foraminal. Loss of muscle strength was evaluated preoperatively and at the last follow-up according to the classification of the Medical Research Council. The disc space was approached anteriorly by a standard cervical supramanubrial Smith-Robinson approach. We identified 19 patients who had undergone C7-T1 discectomy and fusion. The mean age of the sample was 54.26 ± 8.65 years. There was a higher proportion of male patients (57.9%, 11/19). The clinical presentation was predominantly motor deficit in 15/19 cases (78.9%) in intrinsic hand muscles, and usually improved after surgery. The mean follow-up period was 27.05 ± 15.10 months. All the patients underwent an anterior cervical supramanubrial approach with microdiscectomy and fusion. Anterior cervical plate fixation was used in 9/19 cases (47.3%). In the rest of the cases, a stand-alone intervertebral device was placed. An anterior cervical supramanubrial approach was easily accomplished in all patients. Motor deficit was the most common surgical indication. 4.

Anterior transarticular screw fixation as a conventional operation for rigid stabilization.

Background:Anterior transarticular screw (ATS) fixation is a useful surgical option for atlantoaxial (AA) stabilization. This report presents a revised ATS method for AA fusion.Methods:A 79-year-old male presented with AA instability attributed both to an old odontoid fracture and severe degeneration of the lateral atlantoaxial joints (LAAJs). ATS fixation was performed through the conventional anterior cervical approach. The longest screw trajectories were planned preoperatively using multiplanar reconstruction computed tomography (CT) scans, with entry points of the screws situated at the midpoint on the inferior border of the axial body. The surgical exposure was limited to opening at the entry points alone. Our retractor of choice was the Cusco speculum; it sufficiently secured space for utilizing the required instruments for screw placement while offering sufficient protection of soft tissues. Cannulated full-threaded bicortical screws stabilized the LAAJs. Screw insertion required a significant amount of coronal angulation up to the superior articular process of the atlas under open-mouth and lateral fluoroscopy image guidance. After ATS fixation, bone grafting was performed between the posterior laminae of the axis and the atlas through a conventional posterior approach.Results:Bony fusion between the atlas and the axis was confirmed radiographically. Arthrodesis of the LAAJs occurred despite no bone grafting.Conclusions:Rigid fixation of the LAAJs was obtained by our ATS technique, indicating that it is an alternative method for AA fixation when posterior rigid internal fixation is not applicable.

Biomechanics of an integrated interbody device versus ACDF anterior locking plate in a single-level cervical spine fusion construct

Background contextNo profile, integrated interbody cages are designed to act as implants for cervical spine fusion, which obviates the need for additional internal fixation, combining the functionality of an interbody device and the stabilizing benefits of an anterior cervical plate. Biomechanical data are needed to determine if integrated interbody constructs afford similar stability to anterior plating in single-level cervical spine fusion constructs. PurposeThe purpose of this study was to biomechanically quantify the acute stabilizing effect conferred by a single low-profile device design with three integrated screws (“anchored cage”), and compare the range of motion reductions to those conferred by a standard four-hole rigid anterior plate following instrumentation at the C5–C6 level. We hypothesized that the anchored cage would confer comparable postoperative segmental rigidity to the cage and anterior plate construct. Study designBiomechanical laboratory study of human cadaveric spines. MethodsSeven human cadaveric cervical spines (C3–C7) were biomechanically evaluated using a nondestructive, nonconstraining, pure-moment loading protocol with loads applied in flexion, extension, lateral bending (right+left), and axial rotation (left+right) for the intact and instrumented conditions. Range of motion (ROM) at the instrumented level was the primary biomechanical outcome. Spines were loaded quasi-statically up to 1.5 N-m in 0.5 N-m increments and ROM at the C5–C6 index level was recorded. Each specimen was tested in the following conditions:1. Intact2. Discectomy+anchored cage (STA)3. Anchored cage (screws removed)+anterior locking plate (ALP)4. Anchored cage only, without screws or plates (CO) ResultsROM at the C5–C6 level was not statistically different in any motion plane between the STA and ALP treatment conditions (p>.407). STA demonstrated significant reductions in flexion/extension, lateral bending, and axial rotation ROM when compared with the CO condition (p<.022). ConclusionsIn this in vitro biomechanical study, the anchored cage with three integrated screws afforded biomechanical stability comparable to that of the standard interbody cage+anterior plate cervical spine fusion approach. Due to its low profile design, this anchored cage device may avoid morbidities associated with standard anterior plating, such as dysphagia.

Long-Term Evaluation of Dysphasia (Bazaz) with the PCM Cervical Disc Compared to ACDF in a Prospective Randomized Clinical Trial: Five-Year Results from the US IDE Study

The PCM® Cervical Disc is a recently FDA-approved non-constrained cervical disc arthroplasty device with a low-profile design. The investigational device exemption (IDE) clinical trial conducted in the United States is the largest reported multicenter prospective randomized clinical trial explicitly evaluating dysphagia in patients treated with anterior cervical approaches.

Safety and success of parathyroidectomy under local anaesthesia with the classical anterior cervical approach

أهداف البحث استئصال الدريقات (جنيب الدرقية) هو إجراء شائع إلى حد ما، ويؤدى في معظم المراكز المرجعية في أنحاء العالم. في هذه الورقة العلمية عملنا على تقييم جدوى إجراء هذه العملية تحت التخدير الموضعي بدلا من التخدير العام وذلك من حيث السلامة، ونجاح الاستئصال، ومضاعفات ما بعد العملية. طرق البحث أجريت الدراسة في الفترة بين عامي 2006م و 2008م، حيث خضع 22 من المرضى لاستئصال الدريقات تحت التخدير الموضعي في مستشفانا، وكان قد خضع كل المرضى لمسح الدريقات النووي (السيستاميبي) كوسيلة رئيسة لتحديد موقع الدريقة مفرطة الإفراز كما تأكد التشخيص باستخدام مستوى هرمون الدريقات قبل وبعد العملية واعتمد التشخيص النهائي على الفحص التشريحي المرضى (الباثولوجي). النتائج كان الإجراء ناجحا في 21 حالة من أصل 22 حالة وأعمار المرضى تراوحت بين 22 و 74عاما بمتوسط 55.3 ± 11.3 عاما، واحتاج مريض واحد إعادة الاستكشاف تحت تخدير عام في أعقاب العملية الأولى، وكان عدد الدريقات التي أزيلت هو (دريقة واحدة) من 20 مريضا وثلاث من مريض واحد فقط. كان التشريح المرضي (ورم غدي) عند 15 من 22 مريضا، وتضخم وفرط الإفراز عند مريضين، وعند أربع حالات كان التشخيص النهائي مشكوك فيه بين الحالتين. استغرق إجراء العملية ما بين 20 – 60 دقيقة بمتوسط 32.5 دقيقة. ولم تسجل أي مضاعفات للعمليات الجراحية كالقيلة أو إصابة العصب الحنجري بين مرضانا. كما تقبل جميع المرضى التخدير الموضعي، والألم, وتعاونوا بشكل كامل. الاستنتاجات : يمكن إجراء استئصال الدريقات بأمان تحت التخدير الموضعي، مع نسبة نجاح عالية، وانخفاض الوقت اللازم للإجراء الجراحي، وكذلك انخفاض مضاعفات ما بعد الجراحة. الكلمات المفتاحية استئصال الدريقات; التخدير الموضعي; فرط إفراز الدريقات الأولي. Parathyroidectomy is a fairly common procedure in referral centres all over the world. We evaluated the feasibility of performing parathyroidectomy under local anaesthesia instead of general anaesthesia, from the point of view of safety, success and postoperative complications. Between 2006 and 2008, 22 patients aged 22–74 years (mean, 55.3 ± 11.3 years) underwent parathyroidectomy for primary hyperparathyroidism under local anaesthesia at Notre-Dame Hospital, Montreal, Canada. All the patients had a Sestamibi parathyroid scan to localize the hypersecreting gland(s). Diagnosis was confirmed by a rapid test for parathyroid hormone and the final histopathological findings. The procedure was successful in 21 of the 22 cases. One patient required re-exploration under general anaesthesia in subsequent surgery. One gland was removed from 20 patients and three from only one patient. The diagnosis was an adenoma in 15/22 patients, hyperplasia in 2/22 and undetermined in 4/22. The operating time was 20–60 min (mean, 32.5 min). No post-operative haematomas or recurrent laryngeal nerve injury was reported. Pain control and patient tolerance and cooperation were achieved in all cases. Parathyroidectomy can be performed safely under local anaesthesia, with a high success rate and reduced operative time as well as fewer postoperative complications.

Spontaneous cervical intradural disc herniation

Cervical intradural disc herniation (IDH) is a rare condition with very few case reports in the literature. We report a 64-year-old man who presented with sudden onset neck pain and rapidly progressing weakness in the left upper and lower limb. There was no history of trauma. MRI of the cervical spine showed a C6–C7 disc prolapse, for which he underwent a C6–C7 discectomy and fusion with bone graft through an anterior cervical approach. To our knowledge, all patients with a cervical IDH reported in the literature have a traumatic etiology. To the best of our knowledge, we report the first patient with a spontaneous cervical IDH.

Alterations in axial curvature of the cervical spine with a combination of rotation and extension in the conventional anterior cervical approach

Alterations of three-dimensional cervical curvature in conventional anterior cervical approach position are not well understood. The purpose of this study was to evaluate alignment changes of the cervical spine in the position. In addition, simulated corpectomy was evaluated with regard to sufficiency of decompression and perforation of the vertebral artery canal. Fifty patients with cervical spinal disorders participated. Cervical CT scanning was performed in the neutral and supine position (N-position) and in extension and right rotation simulating the conventional anterior approach position (ER-position). Rotation at each vertebral level was measured. With simulation of anterior corpectomy in a vertical direction with a width of 17 mm, decompression width at the posterior wall of the vertebrae and the distance from each foramen of the vertebral artery (VA) were measured. In the ER-position, the cervical spine was rotated rightward by 37.2° ± 6.2° between the occipital bone and C7. While the cervical spine was mainly rotated at C1/2, the subaxial vertebrae were also rotated by several degrees. Due to the subaxial rotation, the simulated corpectomy resulted in smaller decompression width on the left side and came closer to the VA canal on the right side. In the ER-position, the degrees of right rotation of subaxial vertebrae were small but significant. Therefore, preoperative understanding of this alteration of cervical alignment is essential for performing safe and sufficient anterior corpectomy of the cervical spine.

The medial loop of the V2 segment of the vertebral artery and the importance of this variation in correlation with the resection safe zone and technical characteristics of spinal cages during anterior cervical approaches

Dear Editor, Reviewing the literature, the incidence of anatomic variations of the V2 segment of the vertebral artery (VA), is relatively high. Furthermore, ignoring a medial loop of the V2 segment can potentially lead to severe complications during anterior approaches to the cervical spine. We studied the course of 400 vertebral arteries on 190 magnetic resonance imaging and ten contrast-enhanced computed tomography scans from our archive between May 2011 and June 2012. In our study, patients with MRI or CT axial sections from C3 to C7 were included regardless of the underlying pathology. In nine patients (4, 5 %), the V2 segment of the vertebral artery formed a medial loop with distance to the midline 8 mm and 8 mm except in one level (one in 360 cervical levels) [4]. Furthermore, anterior cervical diskectomy 8–10 mm from the midline and width of cervical corpectomy 16–18 mm centered on the midline have been suggested in the literature as safe resection zones [3]. The width and adequacy of cervical corpectomy remains a controversial topic, especially in cases of an unusual medial loop of the V2 segment. It could be technically challenging to avoid the injury of VA and achieve an adequate anterior decompression. Careful choice of cages regarding their width is a prerequisite for anterior cervical diskectomy and corpectomy procedures. According to our study, during drilling for anterior cervical approaches, this variation is likely to be encountered at 7–11 mm depth of vertebral body or intervertebral disk space. In such cases, the application of intraoperative Doppler could be invaluable. Knowledge of the aforementioned anatomic variation of the V2 segment is important for the avoidance of inadvertent injury of the vertebral artery during anterior cervical spine approaches [2], with potentially catastrophic complications for the patient. Given the relatively high incidence of a V2 N. Gkekas (*) :N. Georgakoulias Department of Neurosurgery, Athens General Hospital, G. Gennimatas, Mesogeion 154, Athens, Greece 11526 e-mail: nikolaosgkekasdr@yahoo.gr

Anterior surgical approaches to the cervicothoracic junction: when to use the manubriotomy?

Background contextThe cervicothoracic junction (CTJ) is always a difficult area for anterior approaches. Among them, low anterior cervical approach alone or combined with manubriotomy is the most frequently used. PurposeTo study the need of manubriotomy. Study design/settingComparison of last guidelines proposed in literature. Patient sampleSeven patients treated between March 2010 and March 2011. MethodsAll the patients were scanned on with computed tomography and magnetic resonance of the spinal column before surgery. Measurements by Teng and Karikari were applied in all the cases. An illustrative case is showed. ResultsThe anterior approaches to the CTJ are reviewed. The most recent guidelines by Teng and Karikari are easy to apply and careful. The results obtained were the same in all the cases with good outcome. ConclusionsManubriotomy permits a good exposure of the CTJ area with a low rate of complications. Either Teng and Karikari's guidelines can be used to estabilish the need of manubriotomy.

Topographical anatomy of the anterior cervical approach for c2-3 level

To develop a clinically relevant anterior cervical approach (ACA) to the C2-3 level. Frequently encountered nerves [hypoglossal (HyN), internal (ISLN) and external superior laryngeal nerves (ESLN)] and vessels [lingual (LiA), superior laryngeal (SLA) and superior thyroid arteries (STA)] in the field of high ACA and the anatomic spatial markers [submandibular gland (SMG); sling for digastrics muscle (SDG); hyoid bone (HyB), and thyroid cartilage (ThC)] were evaluated using 18 fresh cadavers. The vertical distance of each structure at the carotid sheath and larynx and each disc for cervical level were measured from the suprasternal notch. The cervical levels of SDG, SMG and HyB were mostly C3 and that of ThC was C5. The vertical locations of HyN and LiA were not significantly different and the levels corresponded to C2. The levels for ISLN and ESLN were C3 at carotid and C4 and C5 at larynx sides, respectively. The vertical locations of ISLN and HyN were significantly different at carotid (p = 0.001) and larynx (p < 0.001) sides. The vertical locations and cervical levels of SLA and STA at carotid and larynx sides were not significantly different with those of ISLN and ESLN, respectively. The HyN traversed C2 with accompanying LiA. The ISLN passed C3 and C4 from carotid to larynx sides and accompanied SLA. The C2-3 level can be exposed through the space between the HyN and the ISLN by retracting the LiA superiorly, the SLA inferiorly, the HyB medially, and the carotid sheath laterally.

Total spondylectomy of C2 and circumferential reconstruction via combined anterior and posterior approach to cervical spine for axis tumor surgery

As a result of the complex anatomy in upper cervical spine, the operative treatment of axis neoplasms is always complicated. Although the procedure for the second cervical vertebra (C2) surgery had been described previously in diverse approaches and reconstruction forms, each has its own limitations and restrictions that usually result in less satisfactory conclusions. The purpose of this study was to evaluate the operation efficacy for axis tumors by using a combined anterior (retropharyngeal) cervical and posterior approach in achieving total resection of C2 and circumferential reconstruction. Eight consecutive C2 tumor patients with mean age of 47.6 years in our institute sequentially underwent vertebra resection and fixation through aforementioned approach from Jan. 2006 to Dec. 2010. No surgical mortality or severe morbidity occurred in our group. In terms of complications, 2 cases developed transient difficulty in swallowing liquids (one of them experienced dysphonia) and 1 developed cerebrospinal fluid leakage (CSFL) that was resolved later. During a mean follow-up period of 31.9 months, the visual analogue scale (VAS) and Japanese orthopedic association (JOA) score revealed that the pain level and neurological function in all patients were improved postoperatively, and there was no evidence of fixation failure and local recurrence. It is concluded that the anterior cervical retropharyngeal approach permits a visible exposure to facilitate the C2 vertebra resection and perform an effective anterior reconstruction at the same time. The custom-made mesh cage applied in our cases can be acted as a firm and convenient implant in circumferential fixation.

Large Perforation of Hypopharynx Secondary to Anterior Cervical Approach : A Complicated Case

Perforation of the hypopharynx, which can occur after anterior cervical approach, is a very rare type of complication. If diagnosed late, it can lead to very fatal course, such as mediastinitis and hematosepsis. Therefore, a precise and prompt diagnosis is crucial. When conservative treatment alone is not expected to heal the perforated site or is likely to lead to serious complications, surgical treatment becomes necessary. This report demonstrates that surgical intervention performed immediately after an early diagnosis can lead to the successful treatment of a large perforation in the hypopharynx on a 58-year-old male patient.

The Efficacy of Carotid Tubercle as an Anatomical Landmark for Identification of Cervical Spinal Level in the Anterior Cervical Surgery: Comparison with Preoperative C-arm Fluoroscopy

BackgroundIn cervical anterior approach, transverse skin incision is preferred due to cosmetic reasons. Precise skin incision is required to reach the surgery segment while minimizing soft tissue injury. Skin incision site is frequently identified using C-arm fluoroscopy or the carotid tubercle. Accordingly, this study was conducted to investigate the efficacy of skin incision using the carotid tubercle as a marker.MethodsThis study was retrospectively conducted on 114 patients who underwent anterior cervical surgery by the same surgeon from April 2004 to June 2012. The rate of the appropriate insertion of K-wire, which was inserted into the disc after anterior approach, into the surgery segment was compared between 62 patients where skin incision site was identified using C-arm fluoroscopy before skin incision and 52 patients where skin incision site was identified using carotid tubercle palpitation before surgery.ResultsThe needle was shown to have been inserted into the planned site in 106 patients out of the total 114 patients. The appropriate insertion of the needle was shown in 59 patients of group I (95.2%) and in 47 patients of group II (90.4%). Although the success rate was higher in group I than group II, it was statistically insignificant. The success rate of one-segment surgery was shown to be 89.7% in group I and 82.6% in group II. Although the success rate was higher in group I than group II, it was statistically insignificant. The success rate of two-segment surgery was shown to be 100% in group I, and 96.4% in group II due to one case of the failure at C3-4 and C5-6. The success rate of three- and four-segment surgeries was shown to be 100% in both groups.ConclusionsThe identification of skin incision site via carotid tubercle palpation was useful for surgeries involving two or more segments. Furthermore, it could be useful for one-segment surgery if surgical site is identified using vertebral body or soft tissues such as longus collis rather than insertion into the disc.

Outcomes Following Cervical Disc Arthroplasty in an Active Duty Military Population

Symptomatic cervical radiculopathy is a common problem in the active duty military population and can cause significant disability leading to limited duty status and loss of operational readiness and strength. Based on their increasing experience with cervical disc arthroplasty (CDA) in this unique patient population, the authors set out to further evaluate the outcomes and complications of CDA in active duty military patients. A retrospective review of a single military tertiary medical center was performed between August 2008 and August 2012 and the clinical outcomes of patients who underwent cervical disc arthroplasty were evaluated. There were 37 active duty military patients, with a total of 41 CDA. The study found good relief of preoperative symptoms (92%) and the ability to maintain operational readiness with a high rate of return to full unrestricted duty (95%) with an average follow-up of 6 months. There was a low rate of complications related to the anterior cervical approach (5%-8%), with no device- or implant-related complications.

Incidence and Risk Factors of the Retropharyngeal Carotid Artery on Cervical Magnetic Resonance Imaging

Retrospective cohort. Define incidence of anomalous carotid vasculature and associated risk factors as pertains to the anterior approach. The carotid artery system, including the common, internal, and external branches, is lateral to the foramen transversarium. If unrecognized, aberrancies in carotid vessel anatomy can lead to devastating complications. A total of 1000 cervical magnetic resonance imagings were screened to localize the carotid artery respective to medial/lateral location of the vessel at each segment from C2-C3 to C6-C7 bilaterally. Vessel location was classified in 3 zones: lateral to the vertebral foramen (type I) (normal); between the lateral foramen and uncoverterbral joint (type II); and medial to the uncovertebral joint (type III). Type III locations were compared with age-matched controls for assessment of cervical alignment via the Ishihara index, C2-C7 angle, and degree of spondylosis. A total of 123 patients demonstrated carotid artery anomalies (type II and III) (12.3%). Twenty-six patients had type III aberrancy (2.6%). Patients with anomalies were significantly older and more likely to be female (60 vs. 51 yr of age, 74% vs. 57% female, respectively, P < 0.05). The type III group average age was 66.1 years and 88% were female. Aberrancies were more likely right-sided and at C3-C4 or cranial. C2-C7 angle showed significantly greater kyphosis in patients with anomalies compared with controls (6.2 vs. 14.4, P = 0.03). The number of severely spondolytic segments was significantly greater in patients with Type III locations than controls (2.0 vs. 1.1 P < 0.05). Carotid arterial anomalies occurred in 12.3% of cases; severe aberrancy was present in 2.6% of patients. In elderly females with kyphotic alignment, a high index of suspicion must be raised for aberrancy. Preoperative assessment of the vasculature in the anterior neck may avoid catastrophic complications.

Foreign body reaction to hydroxyapatite after anterior cervical discectomy with fusion

Dear Editor, The surgical management of cervical disc herniation has greatly evolved over the last century. Shortly after the anterior cervical approach and fusion with a horseshoe bone graft [5], the interbody fusion using autologous iliac bone was described [2], and recent studies have highlighted the morbidity associated with these autografts [3, 8, 9], mainly donor site morbidity and limited supply. Consequently, the use of allograft or synthetic materials for fusion has been increasing. Nevertheless, the fusion rates are similar for the three methods, with synthetic materials averting the pain of autograft bone sourcing and being less expensive than allograft bone use [1, 7]. We are reporting an unexpected complication following the use of phosphocalcic hydroxylapatite after anterior cervical discectomy with fusion. A 68-year-old man with type 2 diabetes mellitus, came to the out–patient clinic of our department complaining of decreased strength on the right limbs. He presented with a right hemiparesis (grade 2) and hemihyposthesia, with ipsilateral gait disturbance; no changes in muscle stretch reflexes were elicited and the Babinsky sign was present on the right side only. The cervical spine MRI revealed right paramedian C4-C5 cervical disc extrusion, with upward and downward migration, and compression of the spine cord. The patient was submitted to surgery: anterior cervical C4-C5 discectomy; fusion with cage filled with autologous bone and hydroxyapatite, and fixation with an anterior plate (over C4 and C5). He recovered motor function, being discharged 48 h later with grade 4 muscle strength and the ability to use the right hand in activities of daily living. However, he was readmitted at 15 days postoperatively with a paraparesis and paraesthesias in both forearms and hands. The MRI showed spinal cord compression at C4-C5 and upward migration of the cage into the C4 vertebral body. He was reoperated and the anterior plate and screws were removed. We did a C4 corpectomy, dissection and excision of epidural tissue and fusion with mesh filled with autologous bone and anterior plate between C3 and C5, with fixed screws over both vertebral bodies. The epidural tissue was sent for microbiology and for histopathology analysis. The patient was treated empirically with a high dose of flucloxacilin for an eventual empyema, and was discharged with partial recovery of autonomous gait with orthosthasis, and no paraesthesies. The microbiological evaluation was negative but neuropathology revealed a foreign body reaction with calcium-positive material surrounded by giant-multinucleated cells (Fig. 1). The patient was followed in the immunoallergy out-patient clinic in order to test hypersensivity to hydroxyapatite, which was negative. At 4 weeks after reoperation, the patient showed a J. P. Lavrador : S. Livraghi Department of Neurosurgery, Hospital de Santa Maria, CHLN, Lisbon, Portugal

A newly developed drill with a polished tip for the anterior cervical approach in spinal canal stenosis: a technical note

The goal of our efforts was to develop a modified drill that allows a safe milling of the dorsal osteophytes located close to the dura. Usually a normal high-speed drill is used for the resection of uncarthrotic and spondylophytic bone. In one patient, we used our new high-speed drill close to the dura in an area, which is not easy reachable with a normal drill or a rongeur. Employing the new drill with a polished tip, the spine surgeon is able to overcome the anatomical restrictions, which he has to face when the anterior approach to the cervical spine. The resection of dorsal osteophytes is easy and safe. The newly developed drill with the polished tip is a safe and high-quality alternative to conventional drills. Further investigations have to be done, to proof the advantages of the new drill.

The surgical approach for cervicothoracic masses in children

BackgroundThe surgical approach to masses located in the cervicothoracic juncton represents a challenge for surgeons. Many techniques have been described with good results. MethodsWe analyzed and compared the results obtained in 2 Italian pediatric surgery centers using 2 different techniques in patients with tumors of the thoracic inlet: center 1, using anterior cervical transsternal approach on 7 patients, and center 2, applying “trap-door” technique on 5 patients. ResultsExcision was incomplete in 5 patients and complete in 7 patients. Histologic examination revealed 5 patients with neuroblastoma; 3, ganglioneuroblastoma; 1, mixoid liposarcoma; 1, desmoid fibromatosis; 1, Castleman disease; and 1, Schwann cell tumor. The median duration of the procedure was 345 minutes in center 1 and 245 minutes in center 2. The median blood loss was 200 mL in both centers. The median hospital stay was 11 days in center 1 and 9 days in center 2. Globally, 5 patients developed postoperative complications. No significant differences were encountered comparing the main surgical outcome parameters between the 2 approaches. ConclusionsBoth techniques resulted in valid options to achieve a safe excision of thoracic inlet masses with a manageable complication rate and acceptable hospital stay. Surgical risk factors should be carefully investigated preoperatively. Postoperative pain control is important to guarantee early recovery.