Standalone titanium/polyetheretherketone interbody cage for anterior lumbar interbody fusion: Clinical and radiological results at 24 months.

Context: Anterior lumbar interbody fusion (ALIF) is a common procedure for patients suffering degenerative, deformity, or posttraumatic pathologies of the lumbar spine. Aims: The aim of this study is to evaluate the clinical and radiological outcomes of a combination Titanium/Polyetheretherketone (Ti/PEEK) 3-screw fixation ALIF cage. Settings and Design: This was a prospective multisurgeon series of 87 patients (105 implants), with a minimum 24-month follow-up. Twelve patients (12/87) were supplemented with posterior percutaneous pedicle screw fixation for additional stability for pars defect spondylolisthesis correction. Radiological follow-up with fine-cut computed tomography (CT) scan occurred at 4-6 months, and again at 18-24 months if no fusion observed on initial CT, was performed to evaluate early and final fusion rates, and integration of the Ti/PEEK cage at the end-plate junction. Clinical follow-up included the subjective measures of pain and functional status and objective wearable device monitoring. Results: The fusion rate was 85% (97/105 implants) 6 months postoperatively, with no implant-related complications, and 95% at 24 months, based on independent radiological assessment. Patients experienced statistically significant improvement in subjective pain and functional outcomes compared to preoperative status. The objective measures revealed a daily step count with a 27% improvement, and gait velocity with a mean increase from 0.97 m/s to 1.18 m/s, at 3 months postoperatively. Conclusions: A Ti/PEEK cage, with allograft and bone morphogenetic protein-2 (BMP-2), achieved rapid interbody progression to fusion and is an effective implant for use in anterior lumbar surgery with high early fusion rates and no peri-endplate lucency. Supercritical CO2 allograft provided an osteoconductive scaffold and combined well with BMP-2 to facilitate fusion.

Intrathecal morphine injection in anterior lumbar and lateral lumbar spine surgery: technical note.

Intrathecal morphine (ITM) is routinely used in many surgical specialties as an adjunct to postoperative analgesia. Patients undergoing lumbar spinal surgery commonly experience early postoperative pain. There have been multiple reports of the benefits of ITM in lumbar spine surgery where it has been shown to significantly reduce the need for intravenous opioid analgesia, improve time to mobilization, and shorten length of hospital stay. ITM is yet to become standard of care in Lumbar Spine Surgery likely due to concerns of it causing a cerebrospinal fluid (CSF) leak. In recent times anterior lumbar spine surgery (ALSS) and lateral lumbar spine surgery (LLSS) have increased in popularity although they are still performed in fewer numbers in comparison to the posterior [posterior lumbar interbody fusion (PLIF)] or transformational [transforaminal lumbar interbody fusion (TLIF)] approaches. Although the number of ALSS and LLSS procedures are increasing, to our knowledge there have been no reports of ITM administered via either approach reported in the literature. Herein we describe an intra-operative technique for injection of morphine into the dural sac via the Anterior and Lateral approaches to the lumbar spine. We propose that this technique can be performed easily and quickly with standard surgical equipment that is commonly available. Through use of this technique, patients undergoing spine surgery may benefit from ITM with minimal risk of iatrogenic CSF leak.

The Case of the Disappearing Colloid Cyst.

BACKGROUND: The natural history of colloid cysts is imperfectly understood, and controversies remain in defining broad management strategies for incidental colloid cysts. The gradual asymptomatic regression of a colloid cyst has not been reported. CASE DESCRIPTION: We present a unique case demonstrating the clinically silent, gradual regression of a colloid cyst over many years. CONCLUSIONS: Gradual regression of a colloid cyst is possible. The philosophical and practical implications of this case on the neurosurgeon's approach to managing patients with colloid cysts are discussed.

Minor Trauma in Ankylosing Spondylitis Causing Combined Cervical Spine Fracture and Esophageal Injury.

BACKGROUND: We illustrate the case of an unstable fracture of the cervical spine in ankylosing spondylitis with associated esophageal injury after minor trauma. CASE DESCRIPTION: A 66-year-old man fell backwards from the first rung of a ladder, sustaining a transverse fracture of the C6 vertebral body and a new diagnosis of ankylosing spondylitis. He was taken for surgical fixation; however, his esophagus was discovered entrapped within the fracture at the time of surgery. Despite the severity of the injury, with surgical reduction, fixation, and esophageal exclusion this patient made a full recovery. CONCLUSION: This case demonstrates the severity of injury after minor trauma in the context of ankylosing spondylitis, the capacity for full recovery in esophageal perforations in spinal trauma, and that clinical suspicion of such injuries allows early diagnosis, treatment, and reduced complications.

Spontaneous Acute Arterial Subdural Hematoma.

BACKGROUND: Spontaneous acute arterial subdural hematoma (SDH) is a rare entity caused by hemorrhage from a cortical perisylvian artery without a known precipitant. CASE DESCRIPTION: A 53-year-old man presented with a 2-day history of acute-onset headache and dysphasia. He had a generalized seizure on arrival to hospital and no history of trauma. A computed tomography demonstrated an acute left-sided SDH. A computed tomography angiogram and a digital subtraction angiogram demonstrated active contrast extravasation into the SDH. A craniotomy was performed to evacuate the hematoma; the bleeding perisylvian artery was visualized and coagulated. CONCLUSIONS: We report a rare case of acute SDH and present a review of the literature. The etiology, investigation, and management of this rare neurosurgical emergency are discussed.

The contribution of the cortical shell to pedicle screw fixation.

BACKGROUND: A pedicle screw insertion technique known as "hubbing" involves the removal of cortical bone around the screw insertion with the aim of improving fixation and decreasing screw loosening. However, the efficacy of this procedure relative to bone density and early loading have not been fully explored. The purpose of this study is to establish the contribution of the cortical layer (hubbing), cancellous density, early loading (toggling) in an idealised model. This is an in vitro laboratory study. METHODS: Synthetic bone blocks with cancellous bulk and a simulated cortical shell were implanted with 6.5 mm pedicle screws. Three key variables were evaluated in this study; density of the simulated bone (10-20 lb/ft3), toggling (±0.5 mm for 10,000 cycles), and the presence or absence of the surrounding cortex (hubbing). Pullout testing after toggling was performed to determine maximum load, stiffness and energy. Results were analyzed to assess interaction and main effects. RESULTS: Removal of the cortex decreased the pullout loads by approximately 1,100 N after toggling. Toggling in the presence of the cortical shell had no effect. However, once the cortical shell is removed damage to the weaker cancellous bone accumulates and further compromises the fixation. CONCLUSIONS: The addition of a cortical layer in the Sawbone model is significant and provides a more realistic model of load sharing. The cortex plays a considerable role in the protection of underlying cancellous bone as well as contributing to initial pullout strength. The results of this study demonstrate a negative synergistic effect when both toggling and hubbing are applied to the weaker bone.

Extra-skeletal Ewing sarcoma of the lumbosacral region in an adult pregnant patient: a case report.

Extra-skeletal Ewing sarcoma in pregnancy is rare. There is thus limited scientific evidence to guide clinicians in its complicated management, particularly within the context of early gestation. We therefore share our successful outcome in a 32-year-old pregnant patient, following a unique management strategy of complete aggressive surgical resection prior to neo-adjuvant therapy. The case involved a 2-month history of right-sided back and gluteal pain, with associated paraesthesia. Lumbosacral magnetic resonance imaging (MRI) revealed an approximate 40×50 mm indeterminate mass in the lower right paraspinal musculature. The mass extended into the first right sacral foramen and the central canal; and also impinged on the S2 exiting nerve. After considering the patients' rapid deterioration, pregnant status and other clinical factors, it was elected to proceed with complete surgical resection prior to any other therapeutic modality. Following surgery, the patient experienced immediate resolution of her pain and by 6 weeks was able to cease the use of all analgesics. At 32-weeks' gestation she underwent an uncomplicated vaginal delivery. At 9 months follow up, she remains disease free and has experienced complete resolution of her back pain and radiculopathy.

Surgical treatment of far lateral lumbar disc herniation: a safe and simple approach.

Lumbar discectomy is one of the most commonly performed neurosurgical procedure. Far lateral disc herniations (FLDH) make up a minor portion of the total discectomy workload for spine surgeons. Due to their lower incidence, as well as their different anatomical positioning compared to the more common para-median disc herniation, the surgical procedures involved in releasing the neural compression caused by FLDHs are often challenging and at times frustrating to most spine surgeons, resulting in suboptimal outcomes for the patient related to the higher risk of spinal instability from facet joint disruption and may even be associated with nerve root injury. We discuss here a safe and simple approach to tackle FLDH.

Rare presentation of Rosai-Dorfman disease mimicking a cervical intramedullary spinal cord tumor.

BACKGROUND: Rosai-Dorfman disease, or sinus histiocytosis with massive lymphadenopathy, is a rare, benign, lymphoproliferative disorder that commonly manifests as a massive painless cervical lymphadenopathy with associated fever and weight loss. Central nervous system involvement is extremely rare, and cervical spinal cord manifestation has not been reported. METHODS: A 76-year-old man presented with a 10-week history of right hemiparesis. Magnetic resonance imaging identified an enhancing cervical intramedullary lesion consistent with a primary spinal cord tumor. RESULTS: Histopathology revealed intramedullary histiocytosis. CONCLUSIONS: This cervical presentation of Rosai-Dorfman disease with central nervous system involvement suggests variation in the clinical manifestations of the disease, necessitating greater surgical awareness.

A rare case of langerhans cell histiocytosis of the skull in an adult: a systematic review.

We report a 41-year old male who presented to the Emergency Department after falling while water-skiing. He had a previous medical history included chronic headaches, which had persisted for the last 2-3 months prior to presentation. Computed tomography of the head showed a small hypersensitivity with a small extra axial collection with a maximum thickness of 1mm. Differential diagnoses included an arachnoid cyst, haemangioma, meningioma or a secondary lesion. A diagnosis of Langerhans Cell Histiocytosis was made based on the histopathology examination and the immunoperoxidase staining.

Cerebral metastasis from malignant pleural mesothelioma.

Malignant mesothelioma is an uncommon, highly invasive tumor derived from the mesothelial cells of pleura or peritoneum characterized by poor outcome. Mesothelioma was thought to metastasize locally only via direct invasion and not have distant spread. Distant metastases were discovered mostly on post-mortem examination. The authors present a case of 62-year-old man with pleural mesothelioma and brain metastasis.

Spinal epidural lipomatosis--a brief review.

Spinal epidural lipomatosis (SEL) is a rare disorder characterized by overgrowth of fat in the extradural space, causing compression of the neural elements. It is frequently associated with the administration of exogenous steroids or elevation of endogenous steroids. We present two patients, both with epidural lipamotosis of idiopathic origin. One was 53-year-old man with progressive mid-thoracic and lower limb pain with associated weakness and neurogenic claudication due to thoracic epidural lipomatosis. The second was a 68-year-old male with lumbar epidural lipomatosis. Co-morbidities for the first patient included diabetes and obesity; however, there was no history of steroid administration. An MRI scan revealed thoracic cord compression, with significant stenosis at T4-T9. The second patient complained of progression of longstanding lumbar pain and claudicant symptoms. There was no history of steroid intake. An MRI revealed stenosis at L4-S1 and diffuse anterior lipomatosis. A literature review revealed 49 cases of idiopathic SEL and 62 of secondary SEL. We aimed to delineate the differences between these two relatively distinct entities including their anatomical distribution, clinical presentation and prognostic implications.

Primary calvarial meningioma.

Primary intraosseous meningioma of the skull is uncommon. We report upon a 50-year-old male patient who presented with a history of an expanding scalp mass over a few months, associated with headache. The mass was initially misdiagnosed as congenital encephalocele. It was observed for 2 months, but the headache increased in severity, and the mass increased in size. Imaging studies showed localized skull expansion at the vertex, and osteolysis of the inner and outer plates of the skull. There was brain tissue herniating through a defect in the inner plate. The patient underwent wide surgical excision, dural repair, and mesh cranioplasty, following which his headaches ceased. Histological examination showed WHO grade I meningioma.

Intracerebral hemorrhage after thrombolytic therapy managed with ventricular drainage.

Intracerebral hemorrhage (ICH) after thrombolytic treatment for acute myocardial infarction (AMI) is a serious complication causing significant morbidity and mortality. Drainage of the haematoma by craniotomy is associated with poor outcome. We present a patient who received tissue plasminogen activator (t-PA) for acute myocardial infarction; he subsequently developed an ICH with ventricular system extension. The patient was managed by insertion of an external ventricular drain. The hemorrhage was successfully evacuated by insertion of the external ventricular drain. This was unexpected as ICH are usually viscous and difficult to aspirate in the acute phase. This suggests that ICHs following thrombolytic therapy remain liquid for up to 10 h. External ventricular drains can be used in the management of patients with ICH complicating thrombolytic therapy for management of acute myocardial infarction or ischemic stroke. This reduces the need for craniotomy and associated morbidity and mortality.