Lumbar reconstruction with hyperlordotic cages: Prediction of neuroforaminal height in comparison to established age and sex dependent reference values.

Interbody cages are routinely used in lumbar reconstruction surgery of deformity cases for restoration of lordosis and sagittal balance of the spine. However, if hyperlordotic implants are inserted into the intervertebral space, special consideration has to be taken concerning the height of the neural foramen during cage implantation. The greater the lordotic angle of the cage is, the higher the posterior size of the cage needs to be in order to avoid neuroforaminal nerve root impingement. In this technical communication, we propose and clinically validate a stepwise mathematic model to predict neuroforaminal height in patients undergoing lumbar reconstruction with hyperlordotic cages. The length of the superior and inferior vertebral end plates including the height of the neural foramen are measured before implantation of the cage in standing sagittal view x-rays. By assumption of an isosceles triangle in combination with the posterior height and the lordotic angle of the cage, the neuroforaminal height after cage implantation can be estimated. By comparison of the predicted neuroforaminal height with age and sex dependent reference values, nerve root impingement can be avoided by selection of the necessary posterior height of the hyperlordotic cage while still gaining sufficient lumbar lordosis.

Multi-rod fixation in spinal neuroarthropathy: a novel surgical technique.

Spinal cord injury (SCI) leads to compromised biomechanical stability due to impaired neuroprotection. This may trigger deformity and destruction of multiple segments of the spine which is known as spinal neuroarthropathy (SNA) or Charcot arthropathy. Surgical treatment of SNA is highly demanding in terms of reconstruction, realignment, and stabilization. In particular, construct failure due to the combination of high shear forces and reduced bone mineral density in the lumbosacral transition zone is a frequent complication in SNA. Notably, up to 75% of SNA patients need multiple revisions within the first year after surgery in order to achieve successful bony fusion. The purpose of this technical report is to present a novel surgical approach with higher overall construct stability to efficiently treat SNA and avoiding repetitive revisions. The new technique of triple rod stabilisation of the lumbosacral transition zone in combination with the introduction of tricortical laminovertebral (TLV) screws is demonstrated in three patients with complete SCI of the thoracic spinal cord. After surgery all patients reported an improvement of the Spinal Cord Independence Measure III (SCIM III) and none of the reported cases showed construct failure within an at least 9 months follow up period. Although TLV screws violate the integrity of the spinal canal, there were no complications with regard to cerebral spinal fluid fistulas and/or arachnopathies so far. The new concept of triple rod stabilization in combination with TLV screws provides improved construct stability in patients with SNA and thus could help to reduce revision and complications rates and improve patient outcome in this disabling degenerative disease.

Spinal cord tethering and syringomyelia after trauma: impact of age and surgical outcome.

Posttraumatic spinal cord tethering and syringomyelia frequently lead to progressive neurological loss. Although several studies demonstrated favourable outcome following spinal cord detethering with/without shunting, additional research is required as no clear consensus exists over the ideal treatment strategy and knowledge about prognostic demographic determinants is currently limited. In this investigation, we retrospectively investigated 67 patients (56 men, 11 women) who were surgically treated and followed for symptomatic spinal cord tethering and syringomyelia from 2012 to 2022 at our center. Age (B-coefficient 0.396) and severity of trauma to the spinal cord (B-coefficient - 0.462) have been identified as independent predictors for the rate of development of symptomatic spinal cord tethering and syringomyelia (p < 0.001). Following untethering surgery including expansion duraplasty with/without shunting, 65.9% of patients demonstrated an improvement of neurological loss (p < 0.001) whereas 50.0% of patients displayed amelioration of spasticity and/or neuropathic pain (p < 0.001). Conclusively, active screening for symptomatic spinal cord tethering and syringomyelia, particularly in younger patients with severe spinal trauma, is crucial as surgical untethering with/without shunting is able to achieve favourable clinical outcomes. This knowledge may enable clinicians to tailor treatment strategies in spinal cord injury patients suffering from progressive neurological loss towards a more optimal and personalized patient care.

Pros and Cons of Early and Very Early Surgery for Traumatic Central Cord Syndrome with Spinal Stenosis: Literature Review and Case Report.

BACKGROUND: The case of a 69-year-old patient with an acute traumatic central cord syndrome (ATCCS) with preexisting spinal stenosis raised a discussion over the question of conservative versus surgical treatment in the acute setting. We provide a literature overview on the management (conservative vs. surgical treatment) of ATCCS with preexisting spinal stenosis. METHODS: We reviewed the literature concerning essential concepts for the management of ATCCS with spinal stenosis and cervical spinal cord injury. The data retrieved from these studies were applied to the potential management of an illustrative case report. RESULTS: Not rarely has ATCCS an unpredictable neurologic course because of its dynamic character with secondary injury mechanisms within the cervical spinal cord in the early phase, the possibility of functional deterioration, and the appearance of a neuropathic pain syndrome during late follow-up. The result of the literature review favors early surgical treatment in ATCCS patients with preexisting cervical stenosis. CONCLUSION: Reluctance toward aggressive and timely surgical treatment of ATCCS should at least be questioned in patients with preexisting spinal stenosis.

Management and outcome of spinal implant-associated surgical site infections in patients with posterior instrumentation: analysis of 176 cases.

PURPOSE: The management of implant-associated surgical site infections (SSI) in patients with posterior instrumentation is challenging. Evidence regarding the most appropriate treatment and the need for removal of implants is equivocal. We sought to evaluate the management and outcome of such patients at our institution. METHODS: We searched our prospectively documented databases for eligible patients with posterior spinal instrumentation, excluding the cervical spine (January 2008-June 2018). Patient files were reviewed, demographic data and treatment details were recorded. Patient-reported outcome (PRO) was assessed with the Core Outcome Measures Index (COMI) preoperatively and postoperatively at 3 and 12 months. RESULTS: A total of 170 patients underwent 210 revisions for 176 SSIs. Two-thirds presented within four weeks (105/176, 59.7%, median 22.5d, 7d-11.1y). The most common pathogens were Staphylococcus aureus (n = 79/210, 37.6%) and Staphylococcus epidermidis (n = 56/210, 26.7%). Debridement and implant retention was performed in 135/210 (64.3%) revisions and partial replacement in 62/210 (29.5%). In 28/176 SSI (15.9%), persistent infection required multiple revisions (≤ 4). Surgery was followed by intravenous and oral antimicrobial treatment (10-12w). In 139/176 SSIs (79%) with ≥ 1y follow-up, infection was cured in 115/139 (82.7%); relapse occurred in 9 (relapse rate: 5.1%). Two patients (1.4%) died. COMI decreased significantly (8.2 ± 1.5 vs. 4.8 ± 2.9, p < 0.0001) over 12 months. 72.7% of patients were (very) satisfied with their care. CONCLUSION: Patients with SSI after posterior (thoraco-)lumbo(-sacral) instrumentation can be successfully treated in most cases with surgical and specific antibiotic treatment. An interdisciplinary approach is recommended. Loose implants should be replaced. In some cases, multiple revisions may be necessary. Patient outcomes were satisfactory.

The debate on apraxia and the supplementary motor area in the twentieth century.

Hand function and apraxia are equally relevant to neurosurgeons: as a symptom, as well as through the functional anatomy of "praxis" which underlies the dexterity needed for neurosurgical practice. The supplementary motor area is crucial for its understanding. Historically, Hugo Liepmann dominated the apraxia debate at the beginning of the twentieth century, a debate that has remained influential until today. Kurt Goldstein, a contemporary of Liepmann, is regularly mentioned as the first to have described the alien hand syndrome in 1909. Wilder Penfield was a key figure in exploring the role of the fronto-mesial cortex in human motor control and coined the term "supplementary motor area". It was Goldstein who not only contributed substantially to the apraxia debate more than 100 years ago; he also established the link between the dysfunction of the fronto-mesial cortex and abnormal higher motor control in humans.

Awake Craniotomy: First-Year Experiences and Patient Perception.

BACKGROUND: Awake craniotomy for brain lesions in or near eloquent brain regions enables neurosurgeons to assess neurologic functions of patients intraoperatively, reducing the risk of permanent neurologic deficits and increasing the extent of resection. METHODS: A retrospective review was performed of a consecutive series of patients with awake craniotomies in the first year of their introduction to our tertiary non-university-affiliated neurosurgery department. Operation time, complications, and neurologic outcome were assessed, and patient perception of awake craniotomy was surveyed using a mailed questionnaire. RESULTS: There were 24 awake craniotomies performed in 22 patients for low-grade/high-grade gliomas, cavernomas, and metastases (average 2 cases per month). Mean operation time was 205 minutes. Failure of awake craniotomy because of intraoperative seizures with subsequent postictal impaired testing or limited cooperation occurred in 2 patients. Transient neurologic deficits occurred in 29% of patients; 1 patient sustained a permanent neurologic deficit. Of the 18 patients (82%) who returned the questionnaire, only 2 patients recalled significant fear during surgery. CONCLUSIONS: Introducing awake craniotomy to a tertiary non-university-affiliated neurosurgery department is feasible and resulted in reasonable operation times and complication rates and high patient satisfaction.