The Postoperative Airway Compromise Score-First Steps to Developing a Postoperative Tool for the Assessment of Upper Airway-Related Complications Following Anterior Cervical Spine Surgery.

BACKGROUND: Acute upper airway compromise is a rare but catastrophic complication after anterior cervical discectomy and fusion. This study aims to develop a score to identify patients at risk of acute postoperative airway compromise (PAC). METHODS: Potential risk factors for acute PAC were selected by a modified Delphi process. Ten patients with acute PAC were identified of 1466 patients who underwent elective anterior cervical discectomy and fusion between July 2014 and May 2019. A comparison group was created by a randomized selection process (non-PAC group). Factors associated with PAC and a P value of < 0.10 were entered into a logistic regression model and coefficients contributed to each risk factor's overall score. Calibration of the model was evaluated using the Hosmer-Lemeshow goodness-of-fit test. Quantitative discrimination was calculated, and the final model was internally validated with bootstrap sampling. RESULTS: We identified 18 potential risk factors from our Delphi process, of which 6 factors demonstrated a significant association with airway compromise: age >65 years, current smoking status, American Society of Anesthesiologists class >2, history of a bleeding disorder, surgery of upper subaxial cervical spine (above C4), and duration of surgery >179 minutes. The final prediction model included 5 predictors with very strong performance characteristics. These 5 factors formed the PAC score, with a range from 0 to 100. A score of 20 yielded the greatest balance of sensitivity (80%) and specificity (88%). CONCLUSIONS: The acute PAC score demonstrates strong performance characteristics. The PAC score might help identify patients at risk of upper airway compromise caused by surgical site abnormalities.

The Effect of Warfarin Use on Postoperative Outcomes after Femoral Neck Surgery.

Introduction: Anticoagulation use in the elderly is common for patients undergoing femoral neck hip surgery. However, its use presents a challenge to balance it with associated comorbidities and benefits for the patients. As such, we attempted to compare the risk factors, perioperative outcomes, and postoperative outcomes of patients who used warfarin preoperatively and patients who used therapeutic enoxaparin. Methods: From 2003 through 2014, we queried our database to determine the cohorts of patients who used warfarin preoperatively and the patients who used therapeutic enoxaparin. Risk factors included age, gender, Body Mass Index (BMI) > 30, Atrial Fibrillation (AF), Chronic Heart Failure (CHF), and Chronic Renal Failure (CRF). Postoperative outcomes were also collected at each of the patients' follow-up visits, including number of hospitalization days, delays to theatre, and mortality rate. Results: The minimum follow-up was 24 months and the average follow-up was 39 months (range: 24-60 months). In the warfarin cohort, there were 140 patients and 2055 patients in the therapeutic enoxaparin cohort. Number of hospitalization days (8.7 vs. 9.8, p = 0.02), mortality rate (58.7% vs. 71.4%, p = 0.003), and delays to theatre (1.70 vs. 2.86, p < 0.0001) were significantly longer for the anticoagulant cohort than the therapeutic enoxaparin cohort. Warfarin use best predicted number of hospitalization days (p = 0.00) and delays to theatre (p = 0.01), while CHF was the best predictor of mortality rate (p = 0.00). Postoperative complications, such as Pulmonary Embolism (PE) (p = 0.90), Deep Vein Thrombosis (DVT) (p = 0.31), and Cerebrovascular Accidents (CVA) (p = 0.72), pain levels (p = 0.95), full weight-bearing status (p = 0.08), and rehabilitation use (p = 0.34) were similar between the cohorts. Conclusion: Warfarin use is associated with increased number of hospitalization days and delays to theatre, but does not affect the postoperative outcome, including DVT, CVA, and pain levels compared to therapeutic enoxaparin use. Warfarin use proved to be the best predictor of hospitalization days and delays to theatre while CHF predicted mortality rate.

Who Needs Surgical Stabilization for Pyogenic Spondylodiscitis? Retrospective Analysis of Non-Surgically Treated Patients.

STUDY DESIGN: Retrospective case series analysis. OBJECTIVE: To identify relevant clinical and radiographic markers for patients presenting with infectious spondylo-discitis associated with spinal instability directly related to the infectious process. METHODS: We evaluated patients presenting with de-novo intervertebral discitis or vertebral osteomyelitis /discitis (VOD) who initiated non-surgical treatment. Patients who failed conservative treatment and required stabilization surgery within 90 days were defined as "failed treatment group" (FTG). Patients who experienced an uneventful course served as controls and were labeled as "nonsurgical group" (NSG). A wide array of baseline clinical and radiographic parameters was retrieved and compared between 2 groups. RESULTS: Overall 35 patients had initiated non-surgical treatment for VOD. 25 patients had an uneventful course (NSG), while 10 patients failed conservative treatment ("FTG") within 90 days. Factors found to be associated with poorer outcome were intra-venous drug abuse (IVDA) as well as the presence of fever upon initial presentation. Radiographically, involvement of the same-level facets and the extent of caudal and rostral VB involvement in both MRI and CT were found to be significantly associated with poorer clinical and radiographic outcome. CONCLUSIONS: We show that clinical factors such as IVDA status and fever as well as the extent of osseous and posterior element involvement may prove to be helpful in favoring surgical treatment early on in the management of spinal infections.

Iliac Screw Fixation Revisited: Improved Clinical and Radiologic Outcomes Using a Modified Iliac Screw Fixation Technique.

STUDY DESIGN: A retrospective study. OBJECTIVE: To describe the modified iliac screw (mILS) technique and compare it to other spinopelvic fixation techniques in terms of wound healing complications, hardware prominence, and failure. SUMMARY OF BACKGROUND DATA: The traditional entry point of an iliac screw often causes postoperative gluteal pain from the prominent screw head. The use of an offset connector also adds a point of weakness to the construct. By choosing a different screw entry point offset connectors can be avoided, and the screw head itself is less prominent, thereby reducing postoperative discomfort. MATERIALS AND METHODS: A retrospective analysis was performed of adult patients undergoing lumbopelvic fixation (LPF) between January 2014 and June 2019. Patients were grouped into 1 of 3 groups based on the technique of pelvic fixation: S2 alar-iliac (S2AI) screw, traditional iliac screw (tILS), and mILS. The primary outcome parameter was the minimal distance from screw head to skin. Secondary outcome parameters were instrumentation loosening/failure, adjacent level fractures, pseudoarthrosis, and medial or lateral iliac screw perforation. RESULTS: A total of 190 patients undergoing LPF were included in the following 3 groups: mILS group (n=113), tILS group (n=40), and S2AI group (n=37). The mean minimal distance from screw head to skin in the mILS group was 31.3 mm compared with 23.7 mm in the tILS group (P<0.00199). No statistically significant differences were found when comparing the 3 groups with respect to complications. The mILS group did not show any cases of prominent instrumentation and had the lowest rate of instrumentation failure. CONCLUSIONS: The mILS technique is an acceptable alternative for LPF, offering the benefits of iliac screw fixation while avoiding offset connectors and screw prominence complications associated with tILS. LEVEL OF EVIDENCE: Level III.

What Are Risk Factors for an Ileus After Posterior Spine Surgery?-A Case Control Study.

STUDY DESIGN: Case-Control Study. OBJECTIVE: The purpose of this retrospective study is to evaluate risk factors for developing a postoperative ileus after posterior spine surgery. METHODS: Patient charts, including radiographs were evaluated retrospectively. Diagnosis of an ileus was confirmed radiographically by a CT scan in all cases. The control group was retrieved by selecting a random sample of patients undergoing posterior spine surgery who did not develop bowel dysfunction postoperatively. RESULTS: A total of 40 patients had a postoperative ileus. The control group consisted of 80 patients. Both groups did not differ significantly in age, gender, BMI, tobacco use, comorbidities or status of previous abdominal surgery. Significant differences between the 2 groups was the length of stay (5.9 vs. 11.2; p = 0.001), surgery in the lumbar spine (47.5% vs. 87.5%; p < 0.001) and major spine surgery involving > 3 levels (35.0% vs. 57.5%; p = 0.019). Patients who suffered from an ileus were more likely to be treated in ICU (23.8% vs. 37.5%; p = 0.115), being re-admitted (0.0% vs 5.0%; p = 0.044) and having a delayed discharge (32.5% vs. 57.5%; p = 0.009). Multivariable analysis demonstrated that lumbar spine surgery compared to thoracic and/or cervical spine surgery (p = 0.00, OR 8.7 CI 2.9-25.4) and major spine surgery involving > 3 levels (p = 0.012; OR 3.0, CI 1.3-7.2) are associated with developing an ileus postoperatively. CONCLUSION: Surgeries of the lumbar spine as well as those involving > 3 levels are associated with developing a postoperative ileus. Further studies are needed to expand on possible risk factors and to better understand the mechanism underlying postoperative ileus in spine surgery patients.

Rates of early complications and mortality in patients older than 80 years of age after surgical treatment of acute traumatic spinal fractures: ankylosing spondylitis versus osteoporosis.

OBJECTIVE: The purpose of this retrospective cohort study was to analyze the early complications and mortality associated with multilevel spine surgery for unstable fractures in patients older than 80 years of age with ankylosing spondylitis and to compare the results with an age- and sex-matched cohort of patients with unstable osteoporotic fractures. METHODS: A retrospective review of the electronic medical records at a single institution was conducted between January 2014 and December 2019. Patient demographics, surgical characteristics, complications, hospital course, and 90-day mortality were collected. Comorbidities were stratified using the age-adjusted Charlson Comorbidity Index (CCI). RESULTS: Among 11,361 surgically treated patients, 22 patients with ankylosing spondylitis (AS group) and 24 patients with osteoporosis (OS group) were identified. The mean ages were 83.1 ± 3.1 years and 83.2 ± 2.6 years, respectively. A significant difference in the mean CCI score was found (7.6 vs 5.6; p < 0.001). Multilevel posterior fusion procedures were conducted in all patients, with 6.7 ± 1.4 fused levels in the AS group and 7.1 ± 1.1 levels fused in the OS group (p > 0.05). Major complications developed in 10 patients (45%) in the AS group compared with 4 patients (17%) in the OS group (p < 0.05). The 90-day mortality was 36% in the AS group compared with 0% in the OS group (p < 0.001). CONCLUSIONS: Patients older than 80 years of age with AS bear a high risk of adverse events after multilevel spinal fusion procedures. The high morbidity and 90-day mortality should be clearly discussed and carefully weighed against surgical treatment.

Surgical Management of Charcot Spinal Arthropathy in the Face of Possible Infection.

BACKGROUND: The design is a retrospective cohort study. Charcot spinal arthropathy (CSA) is a rare and poorly understood progressive destructive spine condition that usually affects patients with preexisting spinal cord injury. The complexity of this condition, especially when additionally burdened by superimposed infection in the CSA zone, can potentially lead to suboptimal management such as protracted antibiotic therapy, predisposition to hardware failure, and pseudarthrosis. While in noninfected CSA primary stabilization is the major goal, staged surgical management has not been stratified based upon presence of a superinfected CSA. We compare clinical and radiological outcomes of surgical treatment in CSA patients with and without concurrent spinal infections. METHODS: Our single-institution database was reviewed for all patients diagnosed with CSA and surgically treated, who were subsequently divided into 2 cohorts: spinal arthropathy with superimposed infection and those without. Those were comparatively studied for complications and reoperation rate. RESULTS: Fifteen patients with CSA underwent surgical intervention; mean follow up of 15.3 months (range, 0-43). Eleven patients received stabilization with a quadruple-rod thoracolumbopelvic construct, while 4 patients with superinfected CSA underwent a staged procedure. Patients treated with a staged approach experienced fewer intraoperative complications (0% versus 18%) and fewer revision surgeries (25% versus 36%). Both cohorts had the same eventual healing. CONCLUSIONS: Surgical management in CSA patients with primary emphasis on stability and modified surgical treatment based on presence of an active infection in the zone of neuropathic destruction will lead to similar eventual successful results with relatively few and manageable complications in this challenging patient population. LEVEL OF EVIDENCE: 4. CLINICAL RELEVANCE: The proposed treatment algorithm including the use of a quadruple-rod construct with lumbopelivic fixation and a staged approach in patients with superinfected CSA represents a reasonable option in the surgical treatment of CSA.

Surgical Treatment of Ossifications of the Cervical Anterior Longitudinal Ligament: A Retrospective Cohort Study.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The study aims to evaluate anterior cervical discectomy and fusion (ACDF) in the treatment of patients with ossification of the anterior longitudinal ligament (OALL). METHODS: We retrospectively reviewed cases performed at our institution between January 2015 and December 2018; adult (age ≥18 years) patients who underwent anterior cervical decompression and fusion in the presence of dysphagia and OALL. Ten patients (9 male, 1 female, mean age 64.4 years) with OALL who underwent ACDF were included. Charts were reviewed for demographics and comorbidities. Primary outcomes assessed were intra- and postoperative complications. Secondary outcomes were fusion rates, instrumentation failure, postsurgical instability/deformity, and readmission rates. RESULTS: The average duration of symptoms prior to surgery was 12.3 months. All patients presented with dysphagia (mean Bazaz score 2.0). The average number of levels with OALL was 4.7 (±1.67). All patients underwent ACDF and 3 patients underwent additional posterior cervical fusion for kyphotic deformity correction or when extensive laminectomy was required. We did not encounter any intraoperative complications. Eight patients (72%) had solid fusion demonstrated on the lateral x-rays and no evidence of progressive kyphotic deformity. We did not encounter any instrumentation failure or loosening. Two patients developed recurrence of dysphagia (Bazaz scores 2 and 3 respectively). CONCLUSION: ACDF for OALL with dysphagia and concomitant myelopathy in our small series of 10 patients demonstrate good fusion and clinical outcomes. Larger studies will be necessary to determine the optimal treatment for patients with dysphagia due to OALL.

Piezo2 expressed in proprioceptive neurons is essential for skeletal integrity.

In humans, mutations in the PIEZO2 gene, which encodes for a mechanosensitive ion channel, were found to result in skeletal abnormalities including scoliosis and hip dysplasia. Here, we show in mice that loss of Piezo2 expression in the proprioceptive system recapitulates several human skeletal abnormalities. While loss of Piezo2 in chondrogenic or osteogenic lineages does not lead to human-like skeletal abnormalities, its loss in proprioceptive neurons leads to spine malalignment and hip dysplasia. To validate the non-autonomous role of proprioception in hip joint morphogenesis, we studied this process in mice mutant for proprioceptive system regulators Runx3 or Egr3. Loss of Runx3 in the peripheral nervous system, but not in skeletal lineages, leads to similar joint abnormalities, as does Egr3 loss of function. These findings expand the range of known regulatory roles of the proprioception system on the skeleton and provide a central component of the underlying molecular mechanism, namely Piezo2.

The iliac pillar - Definition of an osseous fixation pathway for internal and external fixation.

BACKGROUND: Increasing numbers of unstable pelvic ring fractures, due to the ongoing demographic change and improvements in the rescue of high-energy traumatic events, are challenging trauma and orthopedic surgeons. While initial installation of an external fixation device is often necessary, placement of iliac crest pins can be difficult due to the complex osteology of the ilium. HYPOTHESIS: We aim to analyze (1) the length, localization and angulation of the iliac pillar and (2) to define the dimensions of the surgical corridor for a better understanding of pin entry point and trajectory, thus preventing shortcomings in anterior external fixation of pelvic ring injuries. METHODS: Twenty hemipelvises from 10 fresh-frozen cadaveric torsos (3 female, 7 males; mean age 80.2 years) were harvested. The following measurements were taken with digital calipers: Location of the iliac pillar in relation to the anterior superior iliac spine and to the acetabulum roof, mean length and diameter of the iliac pillar, maximum diameter of the iliac pillar. In addition we measured the width of the different bone layers. RESULTS: The mean length of the hourglass shaped iliac pillar was 107.04mm with a mean width of 17.0mm (min. 15.1; max. 19.2). The mean distance to the anterior superior iliac spine was 69.00mm (min. 64.8; max. 73.4). The mean maximum width of the iliac pillar was 12.16mm (min. 9.4; max. 13.8). Caudally the line describing the iliac pillar intercepts the cranial acetabular rim at 12 o'clock. The smallest mean diameter of the cancellous bone was 7.5mm±2.0. CONCLUSION: The iliac pillar is part of the complex osteology of the human pelvis. A cohesive description of its location and dimensions has been lacking. Successful treatment of pelvic fracture depends on an optimal preoperative planning, accurate overall reduction, and stable fixation. We described the origin and angulation to provide a good bone stock for external fixation pin and the width of the different bone layers. This study therefore contributes by facilitating a thorough understanding of pelvic osteology and describing the location and dimensions of an optimal osseous pathway. LEVEL OF EVIDENCE: Anatomical descriptive study.

Antibiotic-impregnated polymethylmethacrylate strut graft as a treatment of spinal osteomyelitis: case series and description of novel technique.

OBJECTIVE: The surgical treatment of osteomyelitis and discitis of the spine often represents a challenging clinical entity for a multitude of reasons, including progression of infection despite debridement, development of spinal deformity and instability, bony destruction, and seeding of hardware. Despite advancement in spinal hardware and implantation techniques, these aforementioned challenges not uncommonly result in treatment failure, especially in instances of heavy disease burden with enough bony endplate destruction as to not allow support of a modern titanium cage implant. While antibiotic-infused polymethylmethacrylate (aPMMA) has been used in orthopedic surgery in joints of the extremities, its use has not been extensively described in the spine literature. Herein, the authors describe for the first time a series of patients treated with a novel surgical technique for the treatment of spinal osteomyelitis and discitis using aPMMA strut grafts with posterior segmental fusion. METHODS: Over the course of 3 years, all patients with spinal osteomyelitis and discitis at a single institution were identified and included in the retrospective cohort if they were surgically treated with spinal fusion and implantation of an aPMMA strut graft at the nidus of infection. Basic demographics, surgical techniques, levels treated, complications, and return to the operating room for removal of the aPMMA strut graft and placement of a traditional cage were examined. The surgical technique consisted of performing a discectomy and/or corpectomy at the level of osteomyelitis and discitis followed by placement of aPMMA impregnated with vancomycin and/or tobramycin into the cavity. Depending on the patient's condition during follow-up and other deciding clinical and radiographic factors, the patient may return to the operating room nonurgently for removal of the PMMA spacer and implantation of a permanent cage with allograft to ultimately promote fusion. RESULTS: Fifteen patients were identified who were treated with an aPMMA strut graft for spinal osteomyelitis and discitis. Of these, 9 patients returned to the operating room for aPMMA strut graft removal and insertion of a cage with allograft at an average of 19 weeks following the index procedure. The most common infections were methicillin-sensitive Staphylococcus aureus (n = 6) and methicillin-resistant S. aureus (n = 5). There were 13 lumbosacral infections and 1 each of cervical and thoracic infection. Eleven patients were cured of their infection, while 2 had recurrence of their infection; 2 patients were lost to follow-up. Three patients required unplanned return trips to the operating room, two of which were for wound complications, with the third being for recurrent infection. CONCLUSIONS: In cases of severe infection with considerable bony destruction, insertion of an aPMMA strut graft is a novel technique that should be considered in order to provide strong anterior-column support while directly delivering antibiotics to the infection bed. While the active infection is being treated medically, this structural aPMMA support bridges the time it takes for the patient to be converted from a catabolic to an anabolic state, when it is ultimately safe to perform a definitive, curative fusion surgery.

Intraoperative Ischemic Stroke in Elective Spine Surgery: A Retrospective Study of Incidence and Risk.

STUDY DESIGN: . Retrospective study. OBJECTIVE: . To determine incidence, risk factors, complications, and early postoperative outcome in patients with intraoperative ischemic stroke during elective spine surgery. SUMMARY OF BACKGROUND DATA: . Overall, stroke is the fifth leading cause of death in the United States and the second leading cause of death worldwide. It can be a catastrophic event and the main cause of neurological disability in adults. METHODS: . A retrospective review of the electronic medical records of patients who underwent elective spine surgery between January 2016 and November 2018 at a larger tertiary referral center was conducted. Patients with infection and neoplastic disease were excluded. Patient demographics, pre- and postoperative neurological status, surgical treatment, surgical time, blood loss, intraoperative abnormalities, risk factors, history of stroke, medical treatment, diagnostics, hospital stay, complications, and mortality were collected. RESULTS: . Out of 5029 surgically treated patients receiving elective spine surgery, a total of seven patients (0.15%) were identified who developed an ischemic stroke during the surgical procedure. Patients were predominantly females (n = 6). Ischemic pontine stroke occurred in two patients. Further distributions of ischemic stroke were: left caudate nucleus, left posterior inferior cerebellar artery, left external capsule, left middle cerebral artery, and acute ischemic supratentorial spots. The main risk factors identified for intraoperative ischemic stroke include hypertension, diabetes, smoking, dyslipidemia, and possibly major intraoperative CSF leak. Three patients (43%) had neurological deficits which did not improve during hospital stay. Two patients recovered fully and two patients died. Therefore, in-hospital mortality rate of this subset of patients was 29%. CONCLUSION: . With the increase of spinal procedures, it is important to identify patients at risk for having an ischemic stroke and to optimize their comorbidities preoperatively. Patients with intraoperative ischemic stroke carry a higher risk for morbidity and mortality during the index hospitalization. LEVEL OF EVIDENCE: 4.

Disaster Scenarios in Spine Surgery: A Survey Analysis.

STUDY DESIGN: Survey analysis among spine surgeons. OBJECTIVE: To identify current consensus and discrepancies in managing adverse intraoperative events among spine surgeons. SUMMARY OF BACKGROUND DATA: Major intraoperative events are not commonly the subject of formal medical training, in part due to the relative paucity of their occurrence and in part due to an insufficient evidence base. Given the clinical impact of appropriate complication management, it is important to identify where surgeons may be able to improve decision making when choosing interventions. METHODS: A survey was created including five hypothetical unpredicted scenarios affecting different organ systems to assess the respondents' preferred reactions. The five clinical vignettes that were selected by the researchers involved: 1) loss of spinal signals in neuro-monitoring, 2) prone position cardiac arrest, 3) prone position hypoxia during thoracic corpectomy and instrumentation, 4) supine cervical vertebral artery injury, and 5) sudden onset hypotension in major prone position reconstructive spine surgery. Twenty-eight surveys (Spine Fellows n = 11; Spine surgeon Faculty n = 17) were completed and returned to the investigators. Results were sorted and ranked according to the frequency each action was identified as a top five choice. RESULTS: Following formal statistical evaluation loss of signals in neuro-monitoring had the statistically significantly most uniform response while the scenario involving cardiac compromise had the most heterogeneous. Many "best" responses had near or complete consensus while some "distractor" possibilities that could harm a patient were also selected by the respondents. CONCLUSION: The heterogeneity of responses in the face of "disaster scenario" intraoperative events shows there is room for more thorough and directed education of spine surgeons during training. As surgical teaching moves toward increased use of patient simulation and situational learning, these vignettes hopefully serve to provide direction for training future spine surgeons on how best to approach difficult situations. LEVEL OF EVIDENCE: 4.

Is There an Optimal Wound Closure Technique for Major Posterior Spine Surgery? A Systematic Review.

STUDY DESIGN: Systematic review. OBJECTIVES: In patients undergoing posterior spinal fusion: (1) What are the types and risks of wound complications in major (≥3 levels) surgery, and does the risk vary by number of levels fused? (2) What types of fascial closure result in the fewest wound complications? (3) What subcutaneous closure technique is more effective in preventing wound complications for obese patients (body mass index >30 kg/m2)? (4) What type of skin closure results in the fewest wound complications? (5) What type of dressing results in the fewest wound complications? METHODS: Electronic databases and reference lists of key articles were searched from January 1, 2000 to December 4, 2017 to identify studies meeting inclusion criteria. RESULTS: Six lower quality retrospective studies (evidence level III) met the inclusion criteria. The risk of wound complications in patients with ≥3 level posterior spine fusion ranges from 1.5% to 3.7% depending on the definition of wound complications. Skin closure with sutures resulted in fewer wound infections compared with staples (0.0% vs 8.0%, P = .023). We were unable to demonstrate an association between the number of levels fused and infection risk. Wound infections, primarily superficial, occurred less frequently with Silverlon dressing versus routine dressing. CONCLUSIONS: We were unable to determine if infection risk changed with increasing number of levels fused. There is a lack of evidence for optimal wound closure technique in posterior spine surgery. Several questions still remain unanswered, such as the optimal fascial closure technique or the optimal subcutaneous closure technique in obese patients.

Extreme Lateral Interbody Fusion Complicated by Fungal Osteomyelitis: Case Report and Quick Review of the Literature.

The authors describe a 67-year-old man with a prior history of alcohol abuse who presented with a complaint of worsening low back pain. Four months prior to his presentation, the patient had undergone extreme lateral interbody fusion (XLIF) of his lumbar 3-4 segment for the treatment of his chronic low back and legs pain. Imaging revealed a loosening of his interbody fusion implant on top of his prior lumbar spine instrumentation. In surgery, the removal of his loose implant was followed by decompression, the stabilization of the collapsed segment, and the implant of antibiotic-impregnated polymethyl-methacrylate (PMMA) spacer and beads. At a later stage, the patient underwent an interbody fusion of the affected segment as well as a segmental fusion from T10 to his pelvis. Whereas all aerobes and anaerobes stains were negative for organisms, multiple fungal smears from the failed segment were positive for yeast, and the patient was placed on oral fluconazole. Infections complicating the surgical site of interbody fusions performed by minimally invasive techniques are rare. To the best of our knowledge and after reviewing the literature, this is the first report of an extreme lateral interbody fusion implant complicated by fungal osteomyelitis.

Risks of Colon Injuries in Extreme Lateral Approaches to the Lumbar Spine: An Anatomical Study.

Introduction The extreme lateral interbody fusion technique (XLIF) is a modification of the retroperitoneal approach to the lumbar spine. This is a minimally invasive technique allowing direct access to the disc space without peritoneal or posterior paraspinal musculature damage. Nevertheless, the retroperitoneal part of the colon can be injured in this operative technique. To our knowledge, a study analyzing the anatomical considerations of the extreme lateral interbody fusion technique with regards to potential colon injuries has not been previously performed. Therefore, the aim of this study was to evaluate the potential risk of colon injuries during the extreme lateral approach to the lumbar spine. Materials and Methods The extreme lateral approach to the lumbar spine was performed on four fresh-frozen cadaveric sides. K-wires were placed into the intervertebral discs and positioned at L1/L2, L2/L3, L3/L4, and L4/L5 levels. Next, the distances from the wires to the most posterior aspect of the adjacent ascending or descending colon were measured. Results The mean distance from the intervertebral disc space to the ascending or descending colon was 23.2 mm at the L2/L3 level, 29.5 mm at the L3/L4 level, and 40.3 mm at the L4/L5 level. The L1/L2 level was above the colon on both sides. Conclusion Our study quantified the relationship of the retroperitoneal colon during an extreme lateral interbody fusion approach. Our results, as well as previously described cases of bowel perforations, suggest a greater risk for colon injuries at the L2/3 and L3/4 levels.​​​​​​​.

S2 Alar-Iliac Screw Insertion: Technical Note with Pictorial Guide.

BACKGROUND: The S2 alar-iliac (S2AI) screw is a modification of the iliac fixation technique using the space between the neuroforamina of S1 and S2 as an insertion point to fix the sacrum to the ilium. To our knowledge, an anatomic review of the S2AI technique has not been described and the insertion point is vague and angles differ in reports from the literature. The purpose of the current anatomic illustration is to provide step-by-step techniques with fluoroscopic imaging to help confirm the safe placement of S2AI screws. METHODS: The procedure was performed on the left and rights sides of a fresh, frozen, and thawed predissected male cadaver in a surgical training facility through a standard posterior midline exposure for placement of the S2AI screws. All screws were placed by a fellowship-trained spine surgeon and an attending spine surgeon. RESULTS: The specimen was placed prone, and a midline incision begun at the L4 or L5 spinous process. Using the anteroposterior and inlet views, the S1 dorsal sacral foramen, the S1 endplate, and the sacroiliac joint can be identified. The insertion point is 10 mm laterally between the S1 and S2 foramina and near to the sacroiliac joint. Aim toward the anterior inferior iliac spine is ensured by using a 30°-40° lateral angulation in the transverse plane and 20°-30° caudal angulation in the sagittal plane depending on the sacral angulation. Using lateral fluoroscopy, the acetabulum and greater sciatic notch can be identified and screw misplacement can be avoided. The screw length is measured and is usually between 60 and 90 mm (8- to 9-mm diameter). An elevator is used to identify the outer sacral cortex. Anteroposterior, obturator-outlet, and teardrop views are used to ensure correct screw insertion. CONCLUSIONS: Fluoroscopic guidance is crucial for optimal S2AI screw placement. Using the described technique allows a safe and correct insertion of the S2AI screw.

Wound Closure After Posterior Multi-level Lumbar Spine Surgery: An Anatomical Cadaver Study and Technical Note.

Meticulous attention to wound closure in posterior lumbar spine surgery is an important principle in reducing surgical site infections. We detail standardized wound closure used for posterior lumbar spine surgery at a tertiary care referral center and illustrate this as a step-by-step cadaveric dissection. The lumbar spine of a cadaveric specimen (male, 73 years at death) was used for dissection. Standardizing wound closure in posterior lumbar spine surgery may help limit wound complications and infection. Some key points of our technique, as demonstrated on a cadaveric specimen, include separating fascial compartments, avoiding suture abscesses, and creating a tension-free wound.

The Proprioceptive System Masterminds Spinal Alignment: Insight into the Mechanism of Scoliosis.

Maintaining posture requires tight regulation of the position and orientation of numerous spinal components. Yet, surprisingly little is known about this regulatory mechanism, whose failure may result in spinal deformity as in adolescent idiopathic scoliosis. Here, we use genetic mouse models to demonstrate the involvement of proprioception in regulating spine alignment. Null mutants for Runx3 transcription factor, which lack TrkC neurons connecting between proprioceptive mechanoreceptors and spinal cord, developed peripubertal scoliosis not preceded by vertebral dysplasia or muscle asymmetry. Deletion of Runx3 in the peripheral nervous system or specifically in peripheral sensory neurons, or of enhancer elements driving Runx3 expression in proprioceptive neurons, induced a similar phenotype. Egr3 knockout mice, lacking muscle spindles, but not Golgi tendon organs, displayed a less severe phenotype, suggesting that both receptor types may be required for this regulatory mechanism. These findings uncover a central role for the proprioceptive system in maintaining spinal alignment.

Cervico-thoracic Interspinous Bursitis Associated with Bilateral Upper-extremity Numbness: A Case Report.

The authors describe a 48-year-old woman suffering from bilateral upper-extremity numbness and axial radiating pain. Magnetic resonance imaging revealed soft-tissue edema and enhancement surrounding the dorsal tip of the C7 spinous process. Excisional biopsy of the lesion revealed a mildly inflamed bursa, with no evidence of an active infection. Removal of the inflamed bursa resulted in complete resolution of the upper-extremity numbness and improvement in her neck pain. Although similar cases have been reported to be associated with rheumatologic conditions, most notably polymyalgia rheumatica (PMR), the current report underlines the presentation of radicular-like complaints associated with interspinous bursitis in the absence of other conditions affecting the musculoskeleton.