Randomized Clinical Trials and Observational Tribulations: Providing Clinical Evidence for Personalized Surgical Pain Management Care Models.

Proving clinical superiority of personalized care models in interventional and surgical pain management is challenging. The apparent difficulties may arise from the inability to standardize complex surgical procedures that often involve multiple steps. Ensuring the surgery is performed the same way every time is nearly impossible. Confounding factors, such as the variability of the patient population and selection bias regarding comorbidities and anatomical variations are also difficult to control for. Small sample sizes in study groups comparing iterations of a surgical protocol may amplify bias. It is essentially impossible to conceal the surgical treatment from the surgeon and the operating team. Restrictive inclusion and exclusion criteria may distort the study population to no longer reflect patients seen in daily practice. Hindsight bias is introduced by the inability to effectively blind patient group allocation, which affects clinical result interpretation, particularly if the outcome is already known to the investigators when the outcome analysis is performed (often a long time after the intervention). Randomization is equally problematic, as many patients want to avoid being randomly assigned to a study group, particularly if they perceive their surgeon to be unsure of which treatment will likely render the best clinical outcome for them. Ethical concerns may also exist if the study involves additional and unnecessary risks. Lastly, surgical trials are costly, especially if the tested interventions are complex and require long-term follow-up to assess their benefit. Traditional clinical testing of personalized surgical pain management treatments may be more challenging because individualized solutions tailored to each patient's pain generator can vary extensively. However, high-grade evidence is needed to prompt a protocol change and break with traditional image-based criteria for treatment. In this article, the authors review issues in surgical trials and offer practical solutions.

Microendoscopic Surgery for Degenerative Disorders of the Cervical and Lumbar Spine: The Influence of the Tubular Workspace on Instrument Angulation, Clinical Outcome, Complications, and Reoperation Rates.

BACKGROUND: Long-term clinical outcomes with microendoscopic spine surgery (MESS) are poorly investigated. The effect of instrument angulation on clinical outcomes has yet to be assessed. METHODS: A total of 229 consecutive patients operated on via two MESS systems were analyzed. Instrument angulation for both MESS systems, which differ from each other regarding the working space for instruments, was assessed using a computer model. Patients' charts and endoscopic video recordings were reviewed to determine clinical outcomes, complications, and revision surgery rates. At a minimum follow-up of two years, clinical outcomes were assessed employing the Neck Disability Index (NDI) and Oswestry Disability Index (ODI). RESULTS: A total of 52 posterior cervical foraminotomies (PCF) and 177 lumbar decompression procedures were performed. The mean follow-up was six years (range 2-9 years). At the final follow-up, 69% of cervical and 76% of lumbar patients had no radicular pain. The mean NDI was 10%, and the mean ODI was 12%. PCF resulted in excellent clinical outcomes in 80% of cases and 87% of lumbar procedures. Recurrent disc herniations occurred in 7.7% of patients. The surgical time and repeated procedure rate were significantly lower for the MESS system with increased working space, whereas the clinical outcome and rate of complication were similar. CONCLUSIONS: MESS achieves high success rates for treating degenerative spinal disorders in the long term. Increased instrument angulation improves access to the compressive pathology and lowers the surgical time and repeated procedure rate.

The Changing Environment in Postgraduate Education in Orthopedic Surgery and Neurosurgery and Its Impact on Technology-Driven Targeted Interventional and Surgical Pain Management: Perspectives from Europe, Latin America, Asia, and The United States.

Personalized care models are dominating modern medicine. These models are rooted in teaching future physicians the skill set to keep up with innovation. In orthopedic surgery and neurosurgery, education is increasingly influenced by augmented reality, simulation, navigation, robotics, and in some cases, artificial intelligence. The postpandemic learning environment has also changed, emphasizing online learning and skill- and competency-based teaching models incorporating clinical and bench-top research. Attempts to improve work-life balance and minimize physician burnout have led to work-hour restrictions in postgraduate training programs. These restrictions have made it particularly challenging for orthopedic and neurosurgery residents to acquire the knowledge and skill set to meet the requirements for certification. The fast-paced flow of information and the rapid implementation of innovation require higher efficiencies in the modern postgraduate training environment. However, what is taught typically lags several years behind. Examples include minimally invasive tissue-sparing techniques through tubular small-bladed retractor systems, robotic and navigation, endoscopic, patient-specific implants made possible by advances in imaging technology and 3D printing, and regenerative strategies. Currently, the traditional roles of mentee and mentor are being redefined. The future orthopedic surgeons and neurosurgeons involved in personalized surgical pain management will need to be versed in several disciplines ranging from bioengineering, basic research, computer, social and health sciences, clinical study, trial design, public health policy development, and economic accountability. Solutions to the fast-paced innovation cycle in orthopedic surgery and neurosurgery include adaptive learning skills to seize opportunities for innovation with execution and implementation by facilitating translational research and clinical program development across traditional boundaries between clinical and nonclinical specialties. Preparing the future generation of surgeons to have the aptitude to keep up with the rapid technological advances is challenging for postgraduate residency programs and accreditation agencies. However, implementing clinical protocol change when the entrepreneur-investigator surgeon substantiates it with high-grade clinical evidence is at the heart of personalized surgical pain management.

Long-term follow-up MRI shows no hastening of adjacent segment degeneration following cervical disc arthroplasty.

Cervical disc arthroplasty is an established procedure, but studies with data on long-term clinical outcome, reoperation for symptomatic adjacent segment degeneration (sASD), and degenerative changes based on MRI findings are rare. Thus, a file review was performed and patients with complete documentation of neurological status at preoperative, postoperative, 12 month, 3-4 years follow-up including surgical reports for reoperation with a minimum follow-up of 9 years were included. Final follow-up assessment included a physical examination, assessment of pain levels, Odoms criteria, Neck disability index. The degeneration of each cervical segment at preoperative and at final follow-up was assessed using an MRI. Forty-six out of 68 included patients participated, the mean follow-up was 11 (range 9-15) years, at which 71.7% of patients were free of arm pain, 52.2% of patients were free of neck pain, 63% of patients had no sensory dysfunction, and full motor strength was noted in 95.6% of patients. The clinical success rate was 76.1%, the mean NDI was 12%. Overall repeated procedure rate was 17%, the reoperation rate for sASD was 9%, and removal of CDA was performed in 4%. MRI showed progressive degeneration but no significant changes of SDI from preoperative to final follow-up.

Anterior cervical discectomy and fusion with a dynamic translational plating versus a rigid carbon fiber reinforced PEEK plating system - a comparison study of radiographic parameters.

PURPOSE: In this study the authors compare the radiographic findings of patients undergoing 1-3 level ACDF a rigid CFRP plate and a translational titanium plate system with a focus on radiographic alignment. MATERIAL AND METHODS: A retrospective review 70 consecutive patients undergoing a 1 to 3 level ACDF for cervical spondylosis was conducted. 2 groups depending on the cervical plating system were created including 38 patients in group 1 (dynamic plate) and 32 in group 2 (rigid CFRP plate). Plain neutral radiographs preoperatively, immediately after surgery and at most recent follow-up were used to assess parameters on sagittal alignment, fusion height, adjacent segment ossification (ASO), fusion rate and implant failure. RESULTS: There were no significant differences between groups preoperatively. Both groups had a more than 12 months follow-up (p = 0.327). Improvement of C2-7 lordosis was seen in both groups but only in group 1 it reached statistical significance at final follow-up. Significant improvement in sagittal segmental alignment was noted in both groups following surgery. A significant sagittal correction of 5.5 ± 9.1 degrees (p = 0.002) was maintained through follow-up only in group 2. No significantly different was seen for segmental fusion rates and loss of fusion height. There were no instances of implant failure within both groups. Worsening of ASO was 20% for both groups. CONCLUSION: ACDF allows for correction and maintenance of cervical alignment. Rigid rigid plate appears more effective at maintaining segmental lordotic correction. The fusion rate and implant failure was not different for both groups.

The Feasibility of C1-C2 Screw-rod Fixation in the Children 5 Years of Age and Younger.

BACKGROUND: Atlantoaxial fixation is technically challenging in younger children. The C1-C2 screw-rod fixation technique is established for adults but limited data about the clinical and radiographical outcome for the treatment of children with 5 years of age or younger is available. METHODS: All files of children who were consecutively treated for spinal disorders were reviewed. Inclusion criteria for further evaluation were: 0 to 5 years of age at initial procedure; detailed surgical report of a posterior C1-C2 fusion with mass lateral and pedicle screw-rod fixation as described by Harms; a minimum clinical and radiographical follow-up of 24 months. The postoperative and last follow-up computed tomography scan and radiographs were used to assess the positioning and stability of the C1-C2 screw-rod construct. RESULTS: Eleven patients (3 boys) with a mean age of 46 months (range: 8 to 66 mo) fulfilled inclusion criteria and were evaluated retrospectively. The mean clinical and radiographical follow-up was 79 months (range: 24 mo to 170 mo). The diagnosis was atlantoaxial rotatory dislocation (4 cases), C1-C2 instability with subluxation (3 cases), atlantoaxial dislocation and os odontoideum (1 case), type II odontoid fracture (1 case), traumatic odontoid epiphysiolysis (1 case), and traumatic rupture of the transverse ligament with C1 subluxation (1 case). Intraoperatively and postoperatively no new neurovascular or vascular complication occurred. C1 lateral mass screws were placed correctly in all cases. Twenty-two C2 pedicle screws were placed correctly (85.7%), and 3 screws showed penetration of the pedicle wall (14.3%). No implant revision, implant failure, and pseudarthrosis were noted. Loss of correction was noted in 1 patient with unilateral C1-C2 fixation and a repeated dorsal fusion procedures were performed. A repeat procedure for implant removal and segmental release was performed in 3 patients to increase the axial rotation of the head. CONCLUSIONS: The C1-C2 screw-rod fixation is a safe technique that achieves solid fixation of the atlantoaxial complex in young children with various disorders. The technique preserves the joint and allows for segmental release via implant removal.

Is Decompression and Partial Discectomy Advantageous Over Decompression Alone in Microendoscopic Decompression Of Monosegmental Unilateral Lumbar Recess Stenosis?

BACKGROUND: Endoscopic techniques are well accepted as surgical technique for decompression of lumbar lateral recess stenosis (LRS). It is uncertain if there is a difference in clinical outcome for decompression alone (DA) or decompression with partial discectomy (DPD) for the treatment of LRS. METHODS: All files of patients who underwent an endoscopic procedure for lumbar LRS were identified from a prospectively collected database. Preoperative magnetic resonance imaging and endoscopic video were analyzed with special focus on the technique of nerve root decompression. Clinical outcome was assessed via a personal examination, a standardized questionnaire including the numeric rating scale (NRS) for leg and back pain, the Oswestry disability index (ODI), and the modified MacNab criteria to assess functional outcome and clinical success. RESULTS: Sixty-six patients were identified of which 57 attended for evaluation (86.4%). DA was performed in 15 (26.3%) patients and DPD in 42 patients (73.7%). The mean follow-up was 45.0 months (range: 16-82 months). Fifty-two patients reported to be free of leg pain (91.1%), 42 patients had no noticeable back pain (73.7%), 49 patients had full muscle strength (85.9%), and 48 patients had no sensory disturbance (84.2%). The mean NRS for leg pain was 1, the mean NRS for back pain was 2, mean ODI was 16% (range: 0%-60%). Clinical success was noted in 49 patients (85.9%) and it was significantly higher for patients following DPD (P = .024). The overall repeat procedure rate was 12% with reoperation rate at the index segment in 10.5% of cases. There were no significant differences with respect to leg and back pain, ODI, and reoperation between both groups. CONCLUSION: Microendoscopic DPD of LRS achieves a 92% clinical success rate which is significantly higher compared to 67% clinical success achieved by DA. There was no significant difference for the rate of reoperation, leg and back pain, and ODI. LEVEL OF EVIDENCE: 4.

The Surgical Treatment of Pyogenic Spondylodiscitis using Carbon-Fiber-Reinforced Polyether Ether Ketone Implants: Personal Experience of a Series of 81 Consecutive Patients.

BACKGROUND: Pyogenic spondylodiscitis (PSD) is a complex disorder that often required postoperative imaging. Carbon-fiber-reinforced polyether ether ketone (CFRP) is radiolucent and offers an optimal assessability of anatomic structures. METHODS: A retrospective file review of patients who were operated on for PSD using CFRP implants was performed to assess the clinical outcome, implant-associated complications, and revision surgery. A minimum follow-up of 3 months was required for evaluation of clinical and radiographic data, which included computed tomography and magnetic resonance imaging (MRI) assessment, to determine implant stability and assessability of soft tissue and nerve structures using a grading system. RESULTS: Eighty-one consecutive patients with a mean of 69.5 years were identified. Debridement and stabilization were performed in 8 cervical, 17 thoracic, and 57 lumbar procedures; 72 interbody fusion procedures using cages were performed. Intraoperatively, no implant-associated complication was noted. The mean follow-up was 7 months, at which 52 patients attended. Improved mobility and reduced pain levels were reported by 87%, and MRI assessability was graded ideal. Residual sign of infection was seen in 5 cases, which influenced antibiotic therapy. Asymptomatic radiolucent zones were identified in 13 patients (16%) and screw loosening in 2 (2.4%). In 1 patient, the pedicle screw tip broke and remained within the vertebral body. A repeated procedure because of progressive vertebral body destruction, implant loosening, or subsidence was performed in 5 patients (6.1%). CONCLUSIONS: The surgical treatment of PSD using CFRP is safe. The repeat procedure rate as a result of implant loosening is 6.1%. Minimal artifacts offer ideal assessability of soft tissue structures on an MRI.

Preoperative Navigated Transcranial Magnetic Stimulation Improves Gross Total Resection Rates in Patients with Motor-Eloquent High-Grade Gliomas: A Matched Cohort Study.

BACKGROUND: Navigated transcranial magnetic stimulation (nTMS) is an established, noninvasive tool to preoperatively map the motor cortex. Despite encouraging reports from few academic centers with vast nTMS experience, its value for motor-eloquent brain surgery still requires further exploration. OBJECTIVE: To further elucidate the role of preoperative nTMS in motor-eloquent brain surgery. METHODS: Patients who underwent surgery for a motor-eloquent supratentorial glioma or metastasis guided by preoperative nTMS were retrospectively reviewed. The nTMS group (n = 105) was pair-matched to controls (non-nTMS group, n = 105). Gross total resection (GTR) and motor outcome were evaluated. Subgroup analyses including survival analysis for WHO III/IV glioma were performed. RESULTS: GTR was significantly more frequently achieved in the entire nTMS group compared to the non-nTMS group (P = .02). Motor outcome did not differ (P = .344). Bootstrap analysis confirmed these findings. In the metastases subgroup, GTR rates and motor outcomes were equal. In the WHO III/IV glioma subgroup, however, GTR was achieved more frequently in the nTMS group (72.3%) compared to non-nTMS group (53.2%) (P = .049), whereas motor outcomes did not differ (P = .521). In multivariable Cox-regression analysis, prolonged survival in WHO III/IV glioma was significantly associated with achievement of GTR and younger patient age but not nTMS mapping. CONCLUSION: Preoperative nTMS improves GTR rates without jeopardizing neurological function. In WHO III/IV glioma surgery, nTMS increases GTR rates that might translate into a beneficial overall survival. The value of nTMS in the setting of a potential survival benefit remains to be determined.

Annular closure device breakage due to recurrent lumbar disc herniation: a case report.

Detailed surgical management, magnetic resonance imaging (MRI), and computer tomography (CT) images of a broken annular closure device (ACD) have not been reported yet. In this case, a 28-year-old male presented with a new onset of radiculopathy three years after lumbar discectomy and placement of an ACD. The CT-myelography and MRI revealed a recurrent disc herniation (RDH) and dislocation of a broken ACD. ACD removal was performed and confirmed breakage due to RDH with scarring around the RDH and displaced ACD. Implant-associated complications and management should be reported in detail in order to enhance knowledge on device-related complications.

3D-exoscopic visualization using the VITOM-3D in cranial and spinal neurosurgery. What are the limitations?

OBJECTIVE: 3D exoscopic visualization in neurosurgical procedures is of interest for several reasons. The VITOM-3D exoscopic system is cheaper compared to the operating microscope (OM) and offers each person involved in the procedure the same image of the operative field. Little is known of limitations of this visualization technique. PATIENTS AND METHODS: Prospectively, a consecutive series 34 procedures were assessed with focus on the following aspects: intraoperative limitation and the cause for a switch to the OM or endoscopy. A standardized questionnaire was answered by each individual involved in the procedure to assess the image quality, illumination, and magnification of the operative field. Intraoperative video recording and pre- and postoperative MRI and CT-scan were analyzed to assess the dimensions of the surgical approach. RESULTS: Sixteen cranial and 18 spinal procedures (10 intra-axial, 6 extra-axial, 6 cervical, and 12 lumbar) were performed by seven neurosurgical attendings, twelve residents and twelve scrub nurses who all completed a standardized questionnaire after each procedure. Handling and identification of anatomical structures was rated equal or superior to the OM in 62 % and over 80 % of cases, respectively. The illumination and magnification of the operative field on the surface was rate in equal od superior in all cases and on the depth it was rated inferior to the OM over 60 % of cases. In one spinal and five cranial procedures a switch to the OM or endoscope were performed for the following reasons: poor illumination (4 cases), tissue identification (1 case), need for fluorescence imaging (1 case). CONCLUSION: 3D exoscopic visualization using the VITOM-3D is best suited for spinal procedures and for extra-axial cranial procedures. In case of small approach dimensions, the illumination and magnification of the depth of the operative field is rated inferior to the OM which resulted in difficulty of tissue identification and a switch to the OM.

Adjacent segment disease following anterior cervical fusion and the presence of surgery for lumbar disc herniation and surgery at the musculoskeletal joints: are they related?

BACKGROUND CONTEXT: A potential correlation between surgery for symptomatic adjacent segment degeneration (sASD) and the development of degenerative disease of the lumbar spine or osteoarthritis of the musculoskeletal joints remains to be determined. PURPOSE: To assess the rate of sASD following anterior cervical discectomy and fusion (ACDF), the rate of lumbar discectomy (LD), and rate of surgery performed for osteoarthritis at the joints of the musculoskeletal in a long term follow-up. STUDY DESIGN/SETTING: Cohort study OUTCOME MEASURES: Repeat procedure for sASD, microsurgical LD (MSD), and/or the musculoskeletal joints (shoulder, knee, hip). PATIENT SAMPLE: Retrospectively, a total of 833 consecutive patients who underwent ACDF for degenerative disorders ≥20 years ago were identified. Charts were reviewed for preoperative neurological status, smoking status, physical labor, and repeat procedures. Missing data lead to exclusion from follow-up assessment. METHODS: At final follow-up the need for pain medication, Neck disability index (NDI), and Odoms criteria were evaluated. An MRI was performed to assess the grade of degeneration of the cervical spine via the segmental degeneration index (SDI). Patients without (group 1) and with (group 2) repeat procedure for sASD were compared. RESULTS: Collectively, 313 patients met inclusion criteria and 136 patients were evaluated. The mean follow-up was 26 years. Clinical success rate according to Odoms was 85.3%, mean NDI was 14.4%, the rate of regular intake of pain medication was 14.7%, the rate of repeated procedure for sASD was 10.3%. MSD was performed in 23.5%, surgery for osteoarthritis of the shoulder, the hip, and the knee were performed in 11.8%, 6.9%, and 27.7%, respectively. The rate of MSD (p=.018) was significantly higher in group 2 compared to group 1. Gender, smoking status, surgery of the musculoskeletal joints, and the grade of degeneration of the cranial and caudal adjacent segments were similar between group 1 and group 2. CONCLUSION: The overall clinical success following ACDF was 85.3%. The rate of repeat procedure for sASD was 10.3% within 26 years. Patients with sASD had a significantly higher rate of MSD and poorer clinical outcome compared to patients without sASD.

The Effect of Cervicodorsal Hemivertebra Resection on Head Tilt and Trunk Shift in Children With Congenital Scoliosis.

BACKGROUND: Congenital scoliosis due to hemivertebra of the cervicodorsal spine is a rare disorder. It might be accompanied by impaired cosmetic appearances such as head tilt and trunk shift. Little is known about the effect of correction of the major curve on head tilt and trunk shift in children. The purpose of this study was to assess radiographic changes of head tilt and trunk shift following posterior hemivertebra resection (PHVR). METHODS: Retrospectively, all children who underwent PHVR at the cervicodorsal spine (C6-Th6) with pedicle screw fixation with a minimum radiographic follow-up of 1 year were identified for further assessment. A total of 5 radiographic parameters were assessed on preoperative, postoperative, and final follow-up radiographs. (1) Head tilt was defined as the angle between the horizontal line and the line through both molars of the maxillary, (2) trunk shift as the angle between the line of the center of C7 to the sacrum and the central sacral vertical line, (3) Cobb angle was used to assess the major curve, (4) cranial, and (5) caudal compensatory curvature. RESULTS: Seven boys and 10 girls with a mean age of 9.0 years at surgery were evaluated. The mean radiographic follow-up was 89.5 months (range: 12 to 166 mo). The mean head tilt reoriented from 6.9 to 1.9 degrees (P<0.001); trunk shift improved from 4.3 to 2.5 degrees after surgery (P=0.100). There was a significant correlation between head tilt and trunk shift on preoperative and postoperative radiographs (P=0.030/0.031). The major curve, and compensatory curvatures were all significantly corrected (P<0.001). Head reorientation was significantly influenced by patient age at surgery. Repeated procedures due to decompensation of the compensatory curvature were performed in 2 cases. CONCLUSIONS: PHVR and pedicle screw fixation is an effective treatment for patients with congenital scoliosis. Surgery achieves a significant correction of the major curve and reorientation of the head postoperatively, and till the last follow-up. LEVEL OF EVIDENCE: Level IV.

Loss of consciousness at onset of aneurysmal subarachnoid hemorrhage in good-grade patients.

Loss of consciousness (LOC) at presentation with aneurysmal subarachnoid hemorrhage (aSAH) has been associated with early brain injury and poor functional outcome. The impact of LOC on the clinical course after aSAH deserves further exploration. A retrospective analysis of 149 aSAH patients who were prospectively enrolled in the Cerebral Aneurysm Renin Angiotensin Study (CARAS) between 2012 and 2015 was performed. The impact of LOC was analyzed with emphasis on patients presenting in excellent or good neurological condition (Hunt and Hess 1 and 2). A total of 50/149 aSAH patients (33.6%) experienced LOC at presentation. Loss of consciousness was associated with severity of neurological condition upon admission (Hunt and Hess, World Federation of Neurosurgical Societies (WFNS), Glasgow Coma Scale (GCS) grade), hemorrhage burden on initial head CT (Fisher CT grade), acute hydrocephalus, cardiac instability, and nosocomial infection. Of Hunt and Hess grade 1 and 2 patients, 21/84 (25.0%) suffered LOC at presentation. Cardiac instability and nosocomial infection were significantly more frequent in these patients. In multivariable analysis, LOC was the predominant predictor of cardiac instability and nosocomial infection. Loss of consciousness at presentation with aSAH is associated with an increased rate of complications, even in good-grade patients. The presence of LOC may identify good-grade patients at risk for complications such as cardiac instability and nosocomial infection.

Endoscopic Posterior Cervical Foraminotomy: 2-Dimensional Operative Video.

In the 1940s, the posterior cervical foraminotomy (PCF) was first described. At that time, this technique represented a big step ahead for the treatment of cervical radiculopathy. Rightly, a multitude of studies demonstrated that open microsurgical posterior foraminotomy is an effective treatment for cervical radiculopathy. Open posterior approaches have still the disadvantage of detaching the extensor cervical muscles from the laminae and the spinous processes, which can lead to severe collateral tissue and muscle damage, followed by postoperative complications, such as axial neck pain, shoulder pain, loss of lordosis, or even spinal instability. Minimally invasive techniques have been developed to reduce the approach related trauma. Initially, these techniques have been performed using endoscopic visualization and applied to the lumbar spine with great success. With this in mind, spine surgeons have extended the spectrum of indication and applied endoscopic techniques to treat degenerative cervical spine disorders. Indications for PCF are single-level or multilevel unilateral lateral disc herniation, osseous foraminal stenosis secondary to isolated facet hypertrophy, and persistent radicular symptoms following an anterior cervical spine procedure. Depending on the underlying pathology, clinical success rates from 75% to 96% for the treatment of cervical radiculopathy have been reported. Mainly, there are 2 different endoscopic techniques to perform PCF. The so-called full-endoscopic techniques are performed under continuous irrigation in single-handed technique. The endoscopic tubular assisted technique is performed in bimanual fashion with microsurgical instruments. The purpose of this video is to describe the endoscopic tubular assisted technique in detail. Patient consent was obtained prior to preparation of the video.

Olfactory dysfunction in patients undergoing supraorbital keyhole craniotomy for clipping of unruptured aneurysms.

Olfactory performance has rarely been assessed in the perioperative phase of elective aneurysm surgery. Here, we assessed the risk for olfactory deterioration following surgical treatment of unruptured cerebral aneurysm via the supraorbital keyhole craniotomy. A retrospective review of patients with electively treated cerebral aneurysms who underwent perioperative assessment of olfactory function using a sniffin' sticks odor identification test between January 2015 and January 2016 was performed. A subgroup of patients without history of subarachnoid hemorrhage, without prior aneurysm treatment, and confirmed olfactory function underwent supraorbital keyhole craniotomy for aneurysm clipping. Microscopic and endoscopic videos were reviewed for this subgroup. Sixty-four patients who underwent elective aneurysm treatment either via surgical clipping or endovascular aneurysm obliteration were identified. Prior to treatment, 4/64 (6.3%) demonstrated bilateral anosmia. Collectively, 14 patients (21.9%) met subgroup criteria of supraorbital keyhole craniotomy for aneurysm clipping. Here, olfactory performance significantly decreased postoperatively on the side of craniotomy (ipsilateral, P = 0.007), whereas contralateral and bilateral olfactory function remained unaltered (P = 0.301 and P = 0.582, respectively). Consequently, 4/14 patients (28.6%) demonstrated ipsilateral anosmia 3 months after surgery. One patient (1/14, 7.1%) also experienced contralateral anosmia resulting in bilateral anosmia. Intraoperative visualization of the olfactory tract and surgical maneuvers do not facilitate prediction of olfactory outcome. The supraorbital keyhole craniotomy harbors a specific risk for unilateral olfactory deterioration. Lack of perioperative olfactory assessment likely results in underestimation of the risk for olfactory decline. Despite uneventful surgery, prediction of postoperative olfactory function and dysfunction remain challenging. Clin. Anat. 33:316-323, 2020. © 2019 Wiley Periodicals, Inc.

Is there a difference in the grade of degeneration at the cervical spine following anterior cervical fusion with respect to clinical outcome, diagnosis, and repeat procedure? An MRI study of 102 patients with a mean follow-up of 25 years.

OBJECTIVE: There is currently no consensus on whether adjacent-segment degeneration (ASD), loss of disc height (DH), and loss of sagittal segmental angle (SSA) are due to anterior cervical discectomy and fusion (ACDF). The purpose of the present study was to assess the grade of segmental degeneration after ACDF and to analyze if there is a difference with respect to clinical outcome, diagnosis, and number of operated levels. METHODS: A total of 102 patients who underwent ACDF with a minimum follow-up of 18 years were retrospectively identified. At final follow-up, the clinical outcome according to Odom's criteria, the Neck Disability Index (NDI), and reoperation for symptomatic ASD (sASD) was assessed. MRI was performed, and DH, SSA, and the segmental degeneration index (SDI, a 5-step grading system that includes disc signal intensity, anterior and posterior disc protrusion, narrowing of the disc space, and foraminal stenosis) were assessed for evaluation of the 2 adjacent and 4 adjoining segments to the ACDF. MRI findings were compared with respect to clinical outcome (NDI: 0%-20% vs > 20%; Odom's criteria: success vs no success), reoperation for sASD, initial diagnosis (cervical disc herniation [CDH] vs cervical spondylotic myelopathy [CSM] and spondylosis), and the number of operated levels (1 vs 2-4 levels). RESULTS: The mean follow-up was 25 years (range 18-45 years), and the diagnosis was CDH in 74.5% of patients and CSM/spondylosis in 25.5%. At follow-up, the mean NDI was 12.4% (range 0%-36%), the clinical success rate was 87.3%, and the reoperation rate for sASD was 15.7%. For SDI, no significant differences were seen with respect to NDI, Odom's criteria, and sASD. Patients diagnosed with CDH had significantly more degeneration at the adjacent segments (cranial, p = 0.015; caudal, p = 0.017). Patients with a 2- to 4-level procedure had less degeneration at the caudal adjacent (p = 0.011) and proximal adjoining (p = 0.019) segments. Aside from a significantly lower DH at the proximal cranial adjoining segment in cases of CSM/spondylosis and without clinical success, no further differences were noted. The degree of SSA was not significantly different with respect to clinical outcome. CONCLUSIONS: No significant differences were seen in the SDI grade and SSA with respect to clinical outcome. The SDI is higher after single-level ACDF and with the diagnosis of CDH. The DH was negligibly different with respect to clinical outcome, diagnosis, and number of operated levels.

Comparison of radiographic parameters after anterior cervical discectomy and fusion with semiconstrained translational versus rotational plate systems.

OBJECTIVE: A plate is commonly applied after anterior cervical discectomy and fusion (ACDF); particularly in cases of multilevel fusion. Recent comparative studies have focused on constrained versus semiconstrained plates, however little data is available to assess differences between semiconstrained plates. PATIENTS AND METHODS: A retrospective review of 60 consecutive adult patients undergoing a 1, 2 or 3 level ACDF with a lordotic allograft for treatment of symptomatic cervical spondylosis was conducted at a single center. The cohort was separated into two groups depending on the cervical plating system used. Patients in the first group had a semiconstrained translational plate and those in the second group had a semiconstrained rotational plate. Plain neutral radiographs were assessed preoperatively, immediately after surgery and at most recent follow-up. The measured radiographic parameters focused on sagittal alignment, adjacent segment pathology, fusion rate and implant failure. RESULTS: There were 30 patients in each group. There were no significant differences in demographic characteristics or distribution of levels fused between groups. All patients had at least 6 months of follow-up and mean follow-up was 14.8 ±â€¯6.2 months in the translational plate group and 13.1 ±â€¯4.8 months in the rotational plate group (p = 0.227). Significant improvement in sagittal segmental alignment was noted in both groups following surgery. The translational plate group improved from 1.0 ±â€¯7.5 degrees to 4.8 ±â€¯7.6 degrees (p = 0.03) and the rotational group improved from 2.7 ±â€¯9.1 degrees to 8.4 ±â€¯7.8 degrees (p = 0.001). This significant sagittal correction was maintained through follow-up for those in the rotational plate group; 5.5 ±â€¯9.1 degrees (p = 0.002). However, a partial loss of segmental lordosis was observed in the translational plate group leading to a failure to maintain significance of the lordotic correction; 1.7 ±â€¯8.3 degrees (p = 0.280) over the follow-up period. Segmental fusion rates were not significantly different between groups. However, there was a higher rate of screw breakage within the rotational plate group (4 instances versus 0 instances in the translational plate group). CONCLUSION: This comparative cohort series suggests that performing an ACDF with a lordotic allograft using either semiconstrained translational or rotational plate system allows for correction and maintenance of cervical alignment, however the rotational plate appears more effective at maintaining segmental lordotic correction. Further prospective controlled study will be needed to determine if this may come at the expense of greater rates of instrumentation failure in the rotational plate group.