Faculty Bibliography

Background/UNASSIGNED:The tethered cord syndrome (TCS) accompanying Chiari-1 (CM-1) malformations and the occult tethered cord syndrome (OTCS) syndrome accompanying the low lying cerebellar tonsil (LLCT) syndrome may be treated with sectioning of the filum terminale (SFT). Methods/UNASSIGNED:Utilizing PubMed, we reviewed the neurosurgical literature to determine how frequently spinal neurosurgeons diagnosed the TCS (e.g., conus terminating below the normal L1-L2 disc level) on lumbar magnetic resonance (MR) studies in patients with CM-1 malformations [e.g. tonsils >5-12 mm below the foramen magnum (FM) warranting SFT]. In addition, we assessed how frequently spinal neurosurgeons encountered the OTCS (e.g., conus normally located at L1-L2 on MR) accompanying the LLCT (e.g., tonsils herniated <5 mm below the FM) also requiring SFT. Results/UNASSIGNED:According to the neurosurgical literature, the incidence of TCS accompanying CM-1 requiring SFT ranged from 2.2% to < 6%, and up to 14%. Few studies additionally highly correlated the OCTS accompanying the LLCT syndrome warranting SFT. Conclusions/UNASSIGNED:Given the differences in the literature, more studies are needed to assess the risks (complications) vs. benefits (improved neurological outcomes) of SFT surgery for TCS with CM-1 and SFT for OCTS with LLCT.

Background/UNASSIGNED:The concept "standard of care" (SOC) is invoked in legal cases, as well as evidence-based, and professional/ethical discussions in medicine and surgery. Methods/UNASSIGNED:We reviewed key legal cases and relevant evidence-based medical articles, and then explored the implications for professional societies seeking to set guidelines for their members testifying as expert witnesses. Results/UNASSIGNED:First, the legal concept of SOC plays a role in malpractice cases in assessing whether a physician's behavior was "within the SOC." The concept of SOC has evolved from a "standard of a responsible body of medical opinion" (Bolam case), which implicitly did not allow for multiple SOC, to a more evidence-based approach. Second, according to the evidence-based medical literature, there is more than one SOC in medicine and surgery, including neurosurgery. Third, professional, medical, and surgical societies have evoked the concept of SOC to set ethical guidelines for how their members should behave when testifying as expert witnesses. Specifically, the literature argues societies should avoid abusing singular, self-serving definitions of the SOC to sanction members, typically plaintiff's experts, who offer alternative SOC in depositions or in court. Conclusions/UNASSIGNED:Recent legal decisions suggest that testimony should be based upon scientific evidence. The scientific evidence indicates that there is often more than one SOC. Thus, any subspecialty society, including the American Association of Neurological Surgeons, that ignores evidence-based medicine and the existence of multiple SOC, risks the appearance of fostering self-interest at the expense of patient care.

Background/UNASSIGNED:Reviewing the neurosurgical literature demonstrated that spinal neurosurgeons rarely (0.78%) diagnose chiari-1 malformation (CM-1) in adults on magnetic resonance (MR) studies defined by tonsillar descent >5 mm below the foramen magnum (FM). Children, averaging 10 years of age, exhibit CM-1 in 96/100,000 cases. According to the literature, fewer spinal neurosurgeons additionally recognize and treat the low lying cerebellar tonsil (LLCT) syndrome. Methods/UNASSIGNED:The normal location of the cerebellar tonsils on cranial/cervical MR averages 2.9 mm ± 3.4 mm above or up to 3 mm below the FM. The neurosurgical literature revealed that most neurosurgeons diagnose and treat CM-1 where the tonsils are >5 mm to an average of 12 mm below the FM. Fewer spinal neurosurgeons additionally diagnose and treat the LLCT syndrome defined by <5 mm of tonsillar descent below the FM. Results/UNASSIGNED:According to the neurosurgical literature, many neurosurgeons perform cranial/spinal decompression with/without fusion and/or duraplasty for CM-1. Fewer neurosurgeons perform these procedures for CM-1 and the LLCT syndrome, for which they additionally perform preoperative cervical traction under anesthesia, and the postoperative placement of occipital neurostimulators (ONS) for intractable headaches following chiari-1/LLCT surgery. Conclusion/UNASSIGNED:Reviewing the literature revealed that spinal neurosurgeons rarely diagnose CM-1, and treat them with decompressions with/without fusions and/or duraplasty. Fewer spinal neurosurgeons diagnose/treat both the CM-1 and LLCT syndromes, perform preoperative traction under anesthesia, and place ONS for persistent headaches following CM-1 surgery.

Background/UNASSIGNED:Prior to spine surgery (SS), we ask whether and when to stop low-dose aspirin (LD-ASA), particularly in patients with significant cardiovascular disease (CAD). Although platelets typically regenerate in 10 days, it can take longer in older patients. Methods/UNASSIGNED:Here we reviewed several studies regarding the perioperative risks/complications [e.g. hemorrhagic complications, estimated blood loss (EBL), continued postoperative drainage] for continuing vs. stopping LD-ASA at various intervals prior to lumbar SS. Results/UNASSIGNED:Multiple studies confirmed the increased perioperative risks for continuing LD-ASA throughout SS, or when stopping it for just 3-7 preoperative days; however, there were no increased risks if stopped between 7 to 10 days postoperatively. Other studies documented no increased perioperative risk for continuing LD-ASA throughout SS, although some indicated increased morbidity (e.g., one patient developed a postoperative hematoma resulting in irreversible paralysis). Conclusions/UNASSIGNED:Several studies demonstrated more hemorrhagic complications if LD-ASA was continued throughout or stopped just 3 to up to 7 days prior to SS. However, there were no adverse bleeding events if stopped from 7-10 days preoperatively. As a spine surgeon who wishes to avoid a postoperative epidural hematoma/paralysis, I would recommend stopping LD-ASA 10 days or longer prior to SS. Nevertheless, each spine surgeon must determine what is in the "best interest" of their individual patient. Certainly, we need future randomized controlled trials to better answer: when and if to stop LD-ASA before spine surgery.

Background/UNASSIGNED:Multiple measures prior to spine surgery may reduce the risks of postoperative surgical site infections (SSIs). Methods/UNASSIGNED:The incidence of SSI following spinal surgery (including reoperations and readmissions) may be markedly reduced by performing less extensive procedures and avoiding fusion where feasible. Preoperative testing up to 3 weeks postoperatively should include other studies to limit the perioperative SSI risk; cardiac stress tests (e.g., older patients/cardiac comorbidities), starting tamsulosin in males over 60 (e.g. avoid urinary retention due to benign prostatic hypertrophy), albumin/prealbumin levels (e.g., low levels increase SSI risk), and HBA1C levels to identify new/treat known diabetics (normalize/reduce preoperative levels). Results/UNASSIGNED:(patients/health-care workers), and bathing 2 weeks preoperatively with chlorhexidine gluconate 4% (not just night before/morning of surgery). Additionally, prior to surgery, the following medications that increase the bleeding risk should be stopped (e.g. for varying periods); anticoagulants, antiplatelet therapies (e.g., aspirin for at least 7-10 days), nonsteroidal anti-inflammatories (NSAIDS: timing depends on the drug), vitamin E, and herbal supplements. Additionally, avoiding elective spinal surgery in morbidly obese patients and recognizing other major medical contraindications to spinal surgery should help reduce infection, morbidity, and mortality rates. Conclusions/UNASSIGNED:Appropriate preoperative and intraoperative prophylactic maneuvers may reduce the risk of postoperative spinal SSI. Specific attention to these details may avoid infections and improve outcomes.

BACKGROUND: Many spine surgeons rely on reports of radiological studies for patients seen routinely in consultation. However, "best practice" should include the spine surgeon's individual assessment of the images themselves to better determine whether the diagnoses rendered were/are correct. METHODS: A now 54-year-old male had an original enhanced magnetic resonance imaging (MR) scan of the cervical spine performed in 2012 that was read as showing mild spondylotic changes at multiple levels. RESULTS: In 2015, the patient presented with a severe spastic quadriparesis, right greater than left, which had markedly worsened over the prior 3 months. Review of the original enhanced MR from 2012 revealed a right-sided C5-C6 tumor (e.g., likely meningioma) filling the right neural foramen with extension into the spinal canal (7 mm x 8 mm x 11 mm): The tumor was originally "missed". The new 2015 enhanced MR scan documented the tumor had enlarged 6.7 fold (measuring 17 mm x 11 mm x 2.2 cm), and now filled 2/3 of the spinal canal, markedly compressing the cord and right C6 nerve root. Following a C4-C6 laminectomy, and a challenging tumor removal, and the patient was neurologically intact. CONCLUSION: This case underscores the need for spine surgeons to carefully review both images and reports of prior diagnostic studies that accompany patients. In this case, the original failure to recognize the tumor led to a 2.5-year delay in surgery that resulted in the patient's severe preoperative quadriparesis, and a much more challenging surgery.

BACKGROUND:Few patients with neurodegenerative disorders (ND) (e.g., Multiple Sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS), and Postpolio Syndrome (PPS)) require spinal surgery. Typically, their neurological symptoms and signs reflect their underlying neurologic disorders rather than structural spinal pathology reported on magnetic resonance images (MR) or computed tomographic scans (CT). METHODS:The first author, a neurosurgeon, reviewed 437 spinal consultations performed over a 20-month period. Of 254 patients seen in first opinion (e.g., had not been seen by a spinal surgeon), 9 had MS, while 2 had ALS. Of 183 patients seen in second opinion (e.g., prior spinal surgeons recommended surgery), 4 had MS, 2 had ALS, and 1 had PPS. We performed this study to establish how often patients with ND, seen in first or second opinion, require spinal surgery. We focused on whether second opinions from spinal surgeons would limit the number of operations offered to these patients. RESULTS:Two of 11 patients with ND seen in first opinion required surgery. The first patient required a C5-7 laminectomy/C2-T2 fusion, followed by a L2-S1 laminectomy/L5S1 fusion. The second patient required a L2-L3 laminectomy/diskectomy/fusion. However, none of the seven patients seen in second opinion, who were previously told by outside surgeons they needed spinal surgery, required operations. CONCLUSIONS:Few patients with neurodegenerative syndromes (MS, ALS, PPS) and reported "significant" spondyloitic spinal disease interpreted on MR/CT studies required surgery. Great caution should be exercised in offering patients with ND spinal surgery, and second opinions should be encouraged to limit "unnecessary" procedures.