Anterior Retropharyngeal Cage Distraction and Fixation for Basilar Invagination: "The Wedge Technique".
ABSTRACT: OBJECTIVE:Surgery is indicated for basilar invagination (BI) in symptomatic patients. In many patients, symptoms and signs occur due to an upward-migrated and malaligned odontoid with fixed or mobile atlantoaxial instability. Posterior distraction and fixation of the atlantoaxial joints has evolved to become the standard of care, but has some inherent morbidity. In this study, we propose that the unilateral anterior submandibular retropharyngeal approach with customized wedge-shaped titanium cages inserted into both atlantoaxial joints and anterior atlantoaxial fixation with a plate screw construct is a safer and easier option in many cases of BI. METHODS:From February 2014 to February 2019, 52 patients (age range, 15-78 years; 40 males and 12 females) with symptomatic BI with atlantoaxial dislocation and minimal sagittal facetal inclination and only mild Chiari malformation without syringomyelia were offered anterior submandibular retropharyngeal atlantoaxial distraction and fixation surgery. RESULTS:Neurological improvement occurred in 80% of patients, while the neurological status of 20% remained unchanged. No patients worsened, and no major complications or mortality was observed. CONCLUSION:In properly selected cases of symptomatic BI, anterior wedge cage distraction with anterior atlantoaxial fixation is a safe and simple option.
Project description:OBJECTIVE:The technique of distraction, compression, extension, and reduction (DCER) is effective to reduce, realign, and relieve cranio-spinal compression through posterior only approach. METHODS:Study included all patients with atlantoaxial dislocation and basilar invagination (BI) with occipitalized C1 arch. Study techniques included Nurick grading, computed tomography scan to study atlanto-dental interval, BI, hyper-lordosis, and neck tilt. Sagittal inclination (SI), coronal inclination (CI), cranio-cervical tilt, presence of pseudo-joints, and anomalous vertebral artery were also noted. Patients underwent DCER with/without joint remodeling or extra-articular distraction (EAD) based on the SI being <100°, 100°-160°, or >160° respectively. In cases with pseudo-joints, joint remodeling was performed in type I and EAD in type II. Customized 'bullet shaped' PSC spacers (n=124) and prototype of the universal craniovertebral junction reducer (UCVJR, n=36) were useful. RESULTS:A total of 148 patients with average age 27.25±17.43 years, ranging from 3 to 71 years (87 males) were operated. Nurick's grading improved from 3.14±1.872 to 1.22±1.17 (p<0.0001). Fifty-two percent of total joints (n=154/296 joints) were either type I (19%)/type II (33%) pseudo-j oints. All traditional indices such as Chamberlein line, McRae line, atlanto-dental interval, and Ranawat line improved (p<at least 0.001). BI, SI, and CI values correlated with type of pseudo-joints (p<0.0001). Side of neck tilt correlated with the type of pseudo-joint (p<0.0001). Cervical hyperlordosis improved significantly (p<0.0001). CONCLUSION:Occipito-C2 pseudo-joints are important in determining the severity of BI. Asymmetrical pseudo-joint causes coronal/neck tilt. Type of pseudo-joint can strategize by DCER. Customized instruments and implants make technique safe, effective and easier.
Project description:Posterior transarticular screw fixation C1-2 with the Magerl technique is a challenging procedure for stabilization of atlantoaxial instabilities. Although its high primary stability favoured it to sublaminar wire-based techniques, the close merging of the vertebral artery (VA) and its violation during screw passage inside the axis emphasizes its potential risk. Also, posterior approach to the upper cervical spine produces extensive, as well as traumatic soft-tissue stripping. In comparison, anterior transarticular screw fixation C1-2 is an atraumatic technique, but has been neglected in the literature, even though promising results are published and lectured to date. In 2004, anterior screw fixation C1-2 was introduced in our department for the treatment of atlantoaxial instabilities. As it showed convincing results, its general anatomic feasibility was worked up. The distance between mid-sagittal line of C2 and medial border of the VA groove resembles the most important anatomic landmark in anterior transarticular screw fixation C1-2. Therefore, CT based measurements on 42 healthy specimens without pathology of the cervical spine were performed. Our data are compiled in an extended collection of anatomic landmarks relevant for anterior transarticular screw fixation C1-2. Based on anatomic findings, the technique and its feasibility in daily clinical work is depicted and discussed on our preliminary results in seven patients.
Project description:The posterior screw fixation in atlas via posterior arch and lateral mass, also called C1 "pedicle" screw, combined with C2 pedicle screw fixiation has shown better biomechanical stability in unstable atlantoaxial fractures. However, its popularization has to fulfill the limitation imposed by anatomical characteristics. The aim of this study was to explore the manipulation, effect, and safety of the atlantoaxial transpedicular screw fixation under "direct vision" for the treatment of unstable atlantoaxial fracture.All the patients diagnosed with unstable atlantoaxial fracture, who received surgery treatment of C1,C2 internal fixation from January 2012 to December 2014 were reviewed. Only these patients that were diagnosed with atlantoaxial unstability secondary to trauma and were treated with atlantoaxial transpedicular screw fixation under "direct vision" and iliac autograft were included. The safety of transpedicular screw placement, postoperative outcome, atlantoaxial stability, autograft fusion, and complications was observed and analyzed retrospectively. The pain visual analog scale (VAS) and the Japanese Orthopedic Association (JOA) score were used as surgical curative effect evaluation standards.We reviewed a total of 92 patients diagnosed with unstable atlantoaxial fracture, who received surgery treatment of C1,C2 internal fixation from January 2012 to December 2014, and 87 patients were treated with atlantoaxial transpedicular screw fixation under "direct vision" and were included this analysis. A total of 306 transpedicular screws in atlas and axis were placed successfully. All cases were followed-up >12 months. The overall breach rate was 11.36%. None of the breaches resulted in new-onset neurological sequela. The neurological status in cases with bilateral upper extremities numbness and lower extremities weakness had improved after surgery. At the latest follow-up, the neck VAS and JOA scores were significantly improved (P?<?.01) than those preoperatively. No cases demonstrated implantation failure and bone graft absorption on the postoperative x-ray films and CT scans.Atlantoaxial transpedicular screw fixation under "direct vision" and iliac autograft for the treatment of unstable atlantoaxial fracture has shown simple manipulation and efficient performance. Thus, the technique of C1-C2 fixation is feasible in treating unstable atlantoaxial fracture.
Project description:INTRODUCTION:Recently, a novel hypothesis has been proposed concerning the origin of craniovertebral junction (CVJ) abnormalities. Commonly found in patients with these entities, atlantoaxial instability has been suspected to cause both Chiari malformation type I and basilar invagination, which renders the tried and tested surgical decompression strategy ineffective. In turn, C1-2 fusion is proposed as a single solution for all CVJ abnormalities, and a revised definition of atlantoaxial instability sees patients both with and without radiographic evidence of instability undergo fusion, instead relying on the intraoperative assessment of the atlantoaxial joints to confirm instability. METHODS:The authors conducted a comprehensive narrative review of literature and evidence covering this recently emerged hypothesis. The proposed pathomechanisms are discussed and contextualized with published literature. CONCLUSION:The existing evidence is evaluated for supporting or opposing sole posterior C1-2 fusion in patients with CVJ abnormalities and compared with reported outcomes for conventional surgical strategies such as posterior fossa decompression, occipitocervical fusion, and anterior decompression. At present, there is insufficient evidence supporting the hypothesis of atlantoaxial instability being the common progenitor for CVJ abnormalities. Abolishing tried and tested surgical procedures in favor of a single universal approach would thus be unwarranted.
Project description:The suprahyoid region extends from the base of the skull to the hyoid bone and includes the pharyngeal, parapharyngeal, parotid, carotid, masticator, retropharyngeal, and perivertebral spaces, as well as the oral cavity. The areas that can be explored by ultrasound include the parotid, carotid, and masticator spaces; the oral cavity; the submandibular and sublingual spaces; the floor of the mouth; and the root of the tongue. The parotid space contains the parotid gland and the excretory duct of Steno, the facial nerve, the external carotid artery, the retromandibular vein, and the intraparotid lymph nodes. The carotid space in the suprahyoid region of the neck contains the internal carotid artery, the internal jugular vein, cranial nerves IX to XII, and the sympathetic plexus. Only some parts of the masticator space can be explored sonographically: these include the masseter muscle, the zygomatic arch and the outer cortex of the ramus of the mandible, and the suprazygomatic portion of the temporalis muscle. The submandibular space houses the submandibular gland, the submental and submandibular lymph nodes, and the anterior belly of digastric muscle. The facial artery and vein and the lower loop of the hypoglossal nerve all pass through the submandibular space. The sublingual space includes the sublingual gland, the deep portion of the submandibular gland and its main excretory duct, the hypoglossal nerve (cranial nerve XII), the lingual nerve (branch of the mandibular branch of trigeminal), and the glossopharyngeal nerve (IX cranial nerve), and the lingual artery and vein. The mylohyoid muscle forms the floor of the mouth. The deepest portion of the oral tongue, the root, consists of the genioglossus and geniohyoid muscles and includes the septum of the tongue. In this article we present the ultrasound features of the structures located in the suprahyoid region of the neck.
Project description:OBJECTIVE:Conventional techniques for atlantoaxial fixation and fusion typically pass cables or wires underneath C1 lamina to secure the bone graft between the posterior elements of C1-2, which leads to complications such as cerebrospinal fluid (CSF) leak and neurological injury. With the evolution of fixation hardware, we propose a novel C1-2 fixation technique that avoids the morbidity and complications associated with sublaminar cables and wires. METHODS:This technique entails wedging and anchoring a structural iliac crest graft between C1 and C2 for interlaminar arthrodesis and securing it using a 0-Prolene suture at the time of C1 lateral mass and C2 pars interarticularis screw fixation. RESULTS:We identified 32 patients who underwent surgery for atlantoaxial with our technique. A 60% improvement in pain-related disability from preoperative baseline was demonstrated by Neck Disability Index (p < 0.001). There were no neurologic deficits. Complications included 2 patients CSF leaks related to presenting trauma, 1 patient with surgical site infection, and 1 patient with transient dysphagia. The rate of radiographic atlantoaxial fusion was 96.8% at 6 months, with no evidence of instrumentation failure, graft dislodgement, or graft related complications. CONCLUSION:We demonstrate a novel technique for C1-2 arthrodesis that is a safe and effective option for atlantoaxial fusion.
Project description:Study Design Retrospective case review. Objective Atlantoaxial instability with and without basilar invagination poses a considerable challenge in management regarding reduction, surgical approach, decompression, instrumentation choice, and extent of fusion. A variety of strategies have been described to reduce and stabilize cranial settling with basilar invagination. Modern instrumentation options included extension to the occiput, C1-C2 transarticular fixation, and C1 lateral mass-C2 pars among others. Since not all cases of cranial settling are the same, their treatment strategies also differ. Factors such as local vascular anatomy, amount of subluxation, need for distraction, and shape of occipital condyles will dictate level and type of instrumentation. The objective of this study was to outline treatment options and provide a rationale for the surgical plan. Methods Two cases of C1-C2 instability in patients with Down syndrome are described. Case 2 underwent C1-C2 instrumented fusion, whereas case 1 involved posterior instrumented fusion to the occiput. Results Both patients tolerated the procedures well. There were no complications. Minimum follow-up was 1 year. There was no loss of reduction. Solid arthrodesis was achieved in both cases. Conclusion Successful reduction can be achieved with both C1-C2 instrumented fusion as well as O-C instrument fusion. Factors such as local vascular anatomy, amount of subluxation, need for distraction, and shape of occipital condyles will dictate level and type of instrumentation.
Project description:Anterior cruciate ligament reconstruction after graft failure may need associated bone correction to ensure stability of the knee. This article presents a technique of posteromedial opening-wedge osteotomy using a custom cutting guide to correct increased tibial slope and metaphyseal varus deformity after recurrent graft failure. An autograft quadriceps tendon graft was selected for the revision anterior cruciate ligament graft. After exposure with an anteromedial incision a patient specific cutting guide was used to make the high tibial osteotomy. The final fixation of the posteromedial opening was achieved using a low-profile locking plate and a femoral head allograft bone wedge. The tibial tunnel was planned and included in the patient-specific cutting guide. The femoral tunnel was placed using an outside to in manner. Bioabsorbable screws were used as fixation devices.
Project description:An excessive posterior tibial slope has been identified as a potential risk factor for anterior cruciate ligament tears. Anterior closing-wedge osteotomy decreases the posterior slope and can eliminate this risk factor in patients with recurrent instability and greater than 12° posterior slope. We will describe an anterior closing-wedge osteotomy technique performed at the tibial tubercle (TT), in which the TT is not detached to preserve the extensor mechanism attachment. A vertical cut is performed in the sagittal plane just posterior to the TT, leaving a distal cortical hinge. Two proximal parallel K-wires and 2 distal parallel K-wires convergent to the proximal ones are inserted from the anterior cortex on both sides of the tubercle toward the tibial posterior cortex at the posterior cruciate ligament's tibial insertion. Proximal and distal cuts are performed to remove the bone wedge. Reduction is achieved by gentle knee extension. Fixation is completed with 2 staples placed medially and laterally to the TT.
Project description:Cervical myelopathy occurs in approximately 2.5% of patients suffering from rheumatoid arthritis (RA) and is associated with notable morbidity and mortality. However, the surgical management of patients affected by cervical involvement in the setting of RA remains challenging and not well studied. To address this, we conducted a retrospective analysis of our clinical database between May 2007 and April 2017, and report on nine patients suffering from cervical myelopathy due to RA. We included patients treated surgically for cervical myelopathy on the basis of diagnosed RA. Clinical findings, treatment and outcome were assessed and reported. In addition, we conducted a narrative review of the literature. Four patients were male. Mean age was 64.8 ± 20.5 years. Underlying cervical pathology was anterior atlantoaxial instability (AAI) associated with retrodental pannus in four cases, anterior atlantoaxial subluxation (AAS) in two cases and basilar invagination in three cases. All patients received surgical treatment via posterior fixation, and in addition two of these cases were combined with a transnasal approach. Preoperative modified Japanese orthopaedic association scale (mJOA) improved from 12 ± 2.4 to 14.6 ± 1.89 at a mean follow-up at 18.8 ± 23.3 months (range 3-60 months) in five patients. In four patients, no follow up was available, and the mJOA of these patients at time of discharge was stable compared to the preoperative score. One patient died two days after surgery, where a pulmonary embolism was assumed to be the cause of mortality, and one patient sustained a temporary worsening of his neurological deficit postoperatively. Surgery is generally an effective treatment method in patients with inflammatory arthropathies of the cervical spine. Given the nature of the RA and potential instability, fixation in addition to cord decompression is generally required.