Perspective: How can risks to patients be limited during spine surgeons' learning curves?

Background: Learning curves (LC) are typically defined by the number of different spinal procedures surgeons must perform before becoming "proficient," as demonstrated by reductions in operative times, estimated blood loss (EBL), length of hospital stay (LOS), adverse events (AE), fewer conversions to open procedures, along with improved outcomes. Reviewing 12 studies revealed LC varied widely from 10-44 cases for open vs. minimally invasive (MI) lumbar diskectomy, laminectomy, transforaminal lumbar interbody fusion (TLIF), anterior lumbar interbody fusion (ALIF), and oblique/extreme lateral interbody fusions (OLIF/XLIF). We asked whether the risks of harm occurring during these LC could be limited if surgeons routinely utilized in-person/intraoperative mentoring (i.e., via industry, academia, or well-trained colleagues). Methods: We evaluated LC for multiple lumbar operations in 12 studies. Results: These studies revealed no LC for open vs. MI lumbar diskectomy. LC required 29 cases for MI laminectomy, 10-44 cases for MI TLIF, 24-30 cases for MI OLIF, and 30 cases for XLIF. Additionally, the LC for MI ALIF was 30 cases; one study showed that 32% of major vascular injuries occurred in the first 25 vs. 0% for the next 25 cases. Shouldn't the risks of harm to patients occurring during these LC be limited if surgeons routinely utilized in-person/intraoperative mentoring? Conclusions: Twelve studies showed that the LC for at different MI lumbar spine operations varied markedly (i.e., 10-44 cases). Wouldn't and shouldn't spine surgeons avail themselves of routine in-person/intraoperative mentoring to limit patients' risks of injury during their respective LC for these varied spine procedures ?

Perspective: Cervical laminoforaminotomy (CLF) is safer than anterior cervical diskectomy/fusion (ACDF) for lateral cervical disease.

Background: The literature documents that laminoforaminotomy (CLF), whether performed open, minimally invasively, or microendoscopically, is safer than anterior cervical diskectomy/fusion (ACDF) for lateral cervical disease. Methods: ACDF for lateral cervical disc disease and/or spondylosis exposes patients to multiple major surgical risk factors not encountered with CLF. These include; carotid artery or jugular vein injuries, esophageal tears, dysphagia, recurrent laryngeal nerve injuries, tracheal injuries, and dysphagia. CLF also exposes patients to lower rates of vertebral artery injury, dural tears (DT)/cerebrospinal fluid fistulas, instability warranting fusion, adjacent segment disease (ASD), plus cord and/or nerve root injuries. Results: Further, CLF vs. ACDF for lateral cervical pathology offer reduced tissue damage, operative time, estimated blood loss (EBL), length of stay (LOS), and cost. Conclusion: CLFs', whether performed open, minimally invasively, or microendoscopically, offer greater safety, major pros with few cons, and decreased costs vs. ACDF for lateral cervical disease.

Perspective: Operate on lumbar synovial cysts and avoid ineffective percutaneous techniques.

Background: Lumbar synovial cysts (LSC), best diagnosed on MR studies, may cause symptoms/signs ranging from unilateral radiculopathy to cauda equina compressive syndromes. Attempts at percutaneous treatment of LSC typically fail. Rather, greater safety/efficacy is associated with direct surgical resection with/without fusion. Methods: Treatment of LSC with percutaneous techniques, including cyst aspiration/perforation, injection (i.e., with/without steroids, saline/other), dilatation, and/or disruption/bursting, classically fail. This is because LSCs' tough, thickened, and adherent fibrous capsules cause extensive thecal sac/nerve root compression, and contain minimal central "fluid" (i.e., "crank-case" and non-aspirable). Multiple percutaneous attempts at decompression, therefore, typically cause several needle puncture sites risking dural tears (DT)/cerebrospinal fluid (CSF) leaks, direct root injuries, failure to decompress the thecal sac/nerve roots, infections, hematomas, and over the longer-term, adhesive arachnoiditis. Results: Alternatively, many studies document the success of direct or even partial resection of LSC (i.e., partial removal with marked cyst/dural adhesions with shrinking down the remnant of capsular tissue). Surgical decompressions of LSC, ranging from focal laminotomies to laminectomies, may or may not warrant additional fusions. Conclusions: Symptomatic LSC are best managed with direct or even partial operative resection/decompression with/without fusion. The use of varying percutaneous techniques classically fails, and increases multiple perioperative risks.

Perspective: Efficacy and outcomes for different lumbar interspinous devices (ISD) vs. open surgery to treat lumbar spinal stenosis (LSS).

Background: Interspinous devices (ISD) constitute a minimally invasive (MI) alternative to open surgery (i.e., laminectomy/decompression with/without fusion (i.e., posterior lumbar interbody fusion (PLIF)/posterolateral instrumented fusion (PLF)) for treating lumbar spinal stenosis (LSS). Biomechanically, static and/or dynamic ISD "offload" pressure on the disc space, increase intervertebral foraminal/disc space heights, reverse/preserve lordosis, limit range of motion (ROM)/stabilize the surgical level, and reduce adjacent segment disease (ASD). Other benefits reported in the literature included; reduced operative time (OR Time), length of hospital stay (LOS), estimated blood loss (EBL), and improved outcomes (i.e., ODI (Oswestry Disability Index), VAS (Visual Analog Scale), and/or SF-36 (Short-Form 36)). Methods: Various studies documented the relative efficacy and outcomes of original (i.e., Wallis), current (i.e., X-STOP, Wallis, DIAM, Aperius PercLID), and new generation (i.e., Coflex, Superion Helifix, In-Space) ISD used to treat LSS vs. open surgery. Results: Although ISD overall resulted in comparable or improved outcomes vs. open surgery, the newer generation ISD provided the greatest reductions in critical cost-saving parameters (i.e., OR time, LOS, and lower reoperation rates of 3.7% for Coflex vs. 11.1% for original/current ISD) vs. original/current ISD and open surgery. Further, the 5-year postoperative study showed the average cost of new generation Coflex ISD/decompressions was $15,182, or $11,681 lower than the average $26,863 amount for PLF. Conclusion: Patients undergoing new generation ISD for LSS exhibited comparable or better outcomes, but greater reductions in OR times, EBL, LOS, ROM, and ASD vs. those receiving original/current ISD or undergoing open surgery.

Anterior cervical surgery for morbidly obese patients should be performed in-hospitals.

Background: Morbid obesity (MO) is defined by the World Health Organization (WHO) as Class II (i.e. Body Mass Index (BMI) >/= 35 kg/M2 + 2 comorbidities) or Class III (i.e. BMI >/= 40 kg/M2). Here, we reviewed the rates for adverse event/s (AE)/morbidity/mortality for MO patients undergoing anterior cervical surgery as inpatients/in-hospitals, and asked whether this should be considered the standard of care? Methods: We reviewed multiple studies to document the AE/morbidity/mortality rates for performing anterior cervical surgery (i.e., largely ACDF) for MO patients as inpatients/in-hospitals. Results: MO patients undergoing anterior cervical surgery may develop perioperative/postoperative AE, including postoperative epidural hematomas (PEH), that can lead to acute/delayed cardiorespiratory arrests. MO patients in-hospitals have 24/7 availability of anesthesiologists (i.e. to intubate/run codes) and surgeons (i.e. to evacuate anterior acute hematomas) who can best handle typically witnessed cardiorespiratory arrests. Alternatively, after average 4-7.5 hr. postoperative care unit (PACU) observation, Ambulatory Surgical Center (ASC) patients are sent to unmonitored floors for the remainder of their 23-hour stays, while those in Outpatient SurgiCenters (OSC) are discharged home. Either for ASC or OSC patients, cardiorespiratory arrests are usually unwitnessed, and, therefore, are more likely to lead to greater morbidity/mortality. Conclusion: Anterior cervical surgery for MO patients is best/most safely performed as inpatients/in-hospitals where significant postoperative AE, including cardiorespiratory arrests, are most likely to be witnessed events, and appropriately emergently treated with better outcomes. Alternatively, MO patients undergoing anterior cervical procedures in ASC/OSC will more probably have unwitnessed AE/cardiorespiratory arrests, resulting in poorer outcomes with higher mortality rates. Given these findings, isn't it safest for MO patients to undergo anterior cervical surgery as inpatients/in-hospitals, and shouldn't this be considered the standard of care?

Places for Healthy Play: A Multi-Pronged Evaluation of Context, Design, and Perceptions for Play Space Improvements.

Community design interventions have prioritized the creation of quality play space, especially in easy to access public places, to improve health outcomes and to reduce health inequities. Evaluations of health-relevant play interventions often fail to assess essential context, design, and perceptions. The Play Everywhere Philadelphia Challenge, led by KABOOM!, funded 16 play spaces to support child health and development and literacy skills for low-income neighborhoods across Philadelphia. In June-October 2022, our interdisciplinary team conducted a process evaluation of completed play space installations (k=9) to identify site aspects that facilitated greater use. We mapped neighborhood context (e.g., child amenities, sociodemographics, pedestrian and bike accessibility), and conducted direct and systematic observations of play space design (e.g., signage, shade), visitation (i.e., number of visitors/hour), and engagement. We summarized visitation and engagement across contextual and design data. While many visitors passed through sites, over half of the children we observed engaged with the installation. Installations with poor condition (i.e., cleanliness and maintenance) had the lowest visitation and engagement. More active/kinetic installations drew more children and engagement. This process evaluation comprehensively analyzed play space design elements and neighborhood context and provides evidence to inform recommendations to increase use of urban play spaces.

Perspective: Postoperative spinal epidural hematomas (pSEH) should be treated, not ignored.

Background: Patients with postoperative spinal epidural hematomas (pSEH) typically require emergency treatment to avoid paralysis; these hematomas should not be ignored. pSEH patients need to undergo immediate MR studies to document the location/extent of their hematomas, and emergent surgical decompression with/ without fusion if warranted. Methods: The frequencies of symptomatic pSEH ranged in various series from 0.1%-4.46%. Major predisposing factors included; perioperative/postoperative coagulation abnormalities/disorders, multilevel spine surgeries, previous spine surgery, and intraoperative cerebrospinal fluid (CSF) leaks. For surgery at all spinal levels, one study observed pSEH developed within an average of 2.7 postoperative hours. Another series found 100% of cervical/thoracic, and 50% of lumbar pSEH were symptomatic within 24 postoperative hrs., while a third series noted a 24-48 postoperative window for pSEH to develop. Results: Early recognition of postoperative symptoms/signs of pSEH, warrant immediate MR examinations to diagnose the local/extent of hemorrhages. Subsequent emergent spinal decompressions/fusions are critical to limit/avert permanent postoperative neurological deficits. Additionally, patients undergoing open or minimally invasive spinal procedures where pSEH are suspected, warrant immediate postoperative MR studies. Conclusion: Patients undergoing spinal surgery at any level typically become symptomatic from pSEH within 2.7 to 24 postoperative hours. Early recognition of new neurological deficits, immediate MR studies, and emergent surgery (i.e., if indicated) should limit/minimize postoperative neurological sequelae. Thus, pSEH should be treated, not ignored.

Perspective; high frequency of intraoperative errors due to extreme, oblique, and lateral lumbar interbody fusions (XLIF, OLIF, LLIF): Are they "safe"?

Background: Extreme Lateral Lumbar Interbody Fusions (XLIF), Oblique Lateral Interbody Fusion (OLIF,) and Lateral Lumbar Interbody Fusion (LLIF) were largely developed to provide indirect lumbar decompressions for spinal stenosis, deformity, and/or instability. Methods: Here, we have reviewed and updated the incidence of intraoperative errors attributed to XLIF, OLIF, and LLIF. Specifically, we focused on how often these procedures caused new neurological deficits, major vessel, visceral, and other injuries, including those warranting secondary surgery. Results: Performing XLIF, OLIF, and LLIF can lead to significant intraoperative surgical errors that include varying rates of; new neurological injuries (i.e. iliopsoas motor deficits (4.3-19.7-33.6-40%), proximal hip/upper thigh sensory loss/dysesthesias (5.1% to 21.7% to 40%)), life-threatneing vascular injuries (i.e., XLIF (0% - 0.4%-1.8%), OLIF (3.2%), and LLIF (2%) involving the aorta, iliac artery, inferior vena cava, iliac vein, and segmental arteries), and bowel/viscarl injuries (0.03%-0.4%) leading to reoperations (i.e., XLIF (1.8%) vs. LLIF (3.8%) vs. XLIF/LLIF/OLIF 2.2%)). Conclusion: Varying reports documented that XLIF, OLIF and LLIF caused up to a 40% incidence of new sensory/motor deficits, up to a 3.2% incidence of major vascular insults, a 0.4% frequency of visceral/bowel perforations, and a 3.8% need for reoperations. These high frequencies of intraoperative surgical errors attributed to XLIF, OLIF, and LLIF should prompt reconsideration of whether these procedures are "safe."

Perspective: Triple intraoperative neurophysiological monitoring (IONM) should be considered the standard of care (SOC) for performing cervical surgery for ossification of the posterior longitudinal ligament (OPLL).

Background: Triple Intraoperative Neurophysiological Monitoring (IONM) should be considered the standard of care (SOC) for performing cervical surgery for Ossification of the Posterior Longitudinal Ligament (OPLL). IONM's three modalities and their alerts include; Somatosensory Evoked Potentials (SEP: =/> 50% amplitude loss; =/>10% latency loss), Motor Evoked Potentials (MEP: =/> 70% amplitude loss; =/>10-15% latency loss), and Electromyography (loss of EMG, including active triggered EMG (t-EMG)). Methods: During cervical OPLL operations, the 3 IONM alerts together better detect intraoperative surgical errors, enabling spine surgeons to immediately institute appropriate resuscitative measures and minimize/avoid permanent neurological deficits/injuries. Results: This focused review of the literature regarding cervical OPLL surgery showed that SEP, MEP, and EMG monitoring used together better reduced the incidence of new nerve root (e.g., mostly C5 but including other root palsies), brachial plexus injuries (i.e., usually occurring during operative positioning), and/or spinal cord injuries (i.e., one study of OPLL patients documented a reduced 3.79% incidence of cord deficits utilizing triple IONM vs. a higher 14.06% frequency of neurological injuries occurring without IONM). Conclusions: Triple IONM (i.e., SEP, MEP, and EMG) should be considered the standard of care (SOC) for performing cervical OPLL surgery. However, the positive impact of IONM on OPLL surgical outcomes critically relies on spinal surgeons' immediate response to SEP, MEP, and/or EMG alerts/significant deterioration with appropriate resuscitative measures to limit/avert permanent neurological deficits.

Perspective: Can intraoperative neurophysiological monitoring (IONM) limit errors associated with lumbar pedicle screw fusions/transforaminal lumbar interbody fusions (TLIF)?

Background: We evaluated whether intraoperative neural monitoring (IONM), including somatosensory evoked potential monitoring (SEP), motor evoked potential monitoring (MEP), and electrophysiological monitoring (EMG), could reduce operative errors attributed to lumbar instrumented fusions, including minimally invasive (MI) transforaminal lumbar interbody fusion (TLIF)/open TLIF. Methods: Operative errors included retraction/stretch or cauda equina neural/cauda equina injuries that typically occurred during misplacement of interbody devices (IBD) and/or malpositioning of pedicle screws (PS). Results: IONM decreased the incidence of intraoperative errors occurring during instrumented lumbar fusions (MI-TLIF/TLIF). In one series, significant loss of intraoperative SEP in 5 (4.3%) of 115 patients occurred after placing IBD; immediate removal of all IBD left just 2 patients with new neural deficits. In other series, firing of trigger EMG's (t-EMG) detected intraoperative PS malpositioning, prompted the immediate redirection of these screws, and reduced the need for reoperations. One t-EMG study required a reoperation in just 1 of 296 patients, while 6 reoperations were warranted out of 222 unmonitored patients. In another series, t-EMG reduced the pedicle screw breech rate to 7.78% (1723 PS) from a higher 11.25% for 1680 PS placed without t-EMG. A further study confirmed that MEP's picked up new motor deficits in 5 of 275 TLIF. Conclusion: SEP/MEP/EMG intraoperative monitoring appears to reduce the risk of surgical errors when placing interbody devices and PS during the performance of lumbar instrumented fusions (MI-TLIF/TLIF).However, IONM is only effective if spine surgeons use it, and immediately address significant intraoperative changes.

Perspective: Transthoracic, posterolateral, or transpedicular approaches to thoracic disks, not laminectomy.

Background: Anterior transthoracic, posterolateral (i.e., costotransversectomy/lateral extracavitary), and transpedicular approaches are now utilized to address anterior, anterolateral, or lateral thoracic disk herniations (TDH). Notably, laminectomy has not been a viable option for treating TDH for decades due to the much lower rate of acceptable outcomes (i.e., 57% for decompressive laminectomy vs. over 80% for the posterolateral, lateral, and transthoracic procedures), and a higher risk of neurological morbidity/paralysis. Methods: Patients with TDH averaged 48-56.3 years of age, and presented with pain (76%), myelopathy (61%-99%), radiculopathy (30%-33%), and/or sphincter loss (16.7%-24%). Those with anterior/anterolateral TDH (30-74%) were usually myelopathic while those with more lateral disease (50-70%) exhibited radiculopathy. Magnetic resonance (MR) studies best defined soft-tissue/disk/cord pathology, CAT scan (CT)/Myelo-CT studies identified attendant discal calcification (i.e. fully calcified 38.9% -65% vs. partial calcification 27.8%), while both exams documented giant TDH filling > 30 to 40% of the canal (i.e., in 43% to 77% of cases). Results: Surgical options for anterior/anterolateral TDH largely included transthoracic or posterolateral approaches (i.e. costotransversectomy, lateral extracavitary procedures) with the occasional use of transfacet/transpedicular procedures mostly applied to lateral disks. Notably, patients undergoing transthoracic, lateral extracavitary/costotransversectomy/ transpedicular approaches may additionally warrant fusions. Good/excellent outcomes were quoted in from 45.5% to 87% of different series, with early postoperative adverse events reported in from 14 to 14.6% of patients. Conclusion: Anterior/anterolateral TDH are largely addressed with transthoracic or posterolateral procedures (i.e. costotransversectomy/extracavitary), with a subset also utilizing transfacet/transpedicular approaches typically adopted for lateral TDH. Laminectomy is essentially no longer considered a viable option for treating TDH.

Can anterior cervical diskectomy/fusion (ACDF) be safely performed in ambulatory surgical centers (ASC's)?

Background: Can anterior cervical diskectomy/fusion (ACDF) be safely performed in ambulatory surgical centers (ASC's: i.e. discharges 4-7.5 hr. postoperatively) that meet the following stringent "exclusion criteria"; elevated Body Mass Index (BMI), major comorbidities, age > 65, American Society of Anesthesiology (ASA) scores > II, and largely multilevel ACDF. Materials: Presently, most ACDF are still being performed in hospital-based outpatient surgical centers (HBSC: utilizing 23-hour stays), or as inpatients. Results: Notably, unreliable disparate study designs involving very different patient populations resulted in nearly comparable, but implausible outcomes for 1-level vs. multilevel ACDF series performed in ASC. A summary of these outcome data included the following rates of; i.e. postoperative hospital transfers (0-6%), 30-day (up to 2.2%), and up to 90 day (2.2%) emergency department (ED) visits, readmissions, and reoperations. Conclusion: Nevertheless, it is just common sense that "less should be less", that 1-level ACDF should involve less risk compared with multilevel ACDF procedures performed in ASC.

Perspective: Early direct repair of recurrent postoperative cerebrospinal (CSF) fluid leaks: No good evidence epidural blood patches (EBP) work.

Background: "Targeted" epidural blood patches (EBP)" successfully treat "focal dural tears (DT)" diagnosed on thin-cut MR or Myelo-CT studies. These DT are largely attributed to; epidural steroid injections (ESI), lumbar punctures (LP), spinal anesthesia (SA), or spontaneous intracranial hypotension (SICH). Here we asked whether "targeted EBP" could similarly treat MR/Myelo-CT documented recurrent post-surgical CSF leaks/DT that have classically been effectively managed with direct surgical repair. Methods: Utilizing ultrasound, fluoroscopy, or O-arm guidance, "targeted EBP" effectively manage "focal DT" attributed to ESI, LP, SA, or SICH. Here we reviewed the literature to determine whether similar "targeted EBP" could effectively manage recurrent postoperative CSF leaks/DT. Results: We were only able to identify 3 studies involving just 20 patients that attempted to utilize EBP to control postoperative CSF fistulas/DT. EBP controlled CSF fistulas/DT in 6 patients in the first study, and 9 of 10 patients (i.e. 90%: 2/2 cervical; 7/8 lumbar) in the second study. However, in the third study, 3 (60%) of 5 EBP failed to avert recurrent CSF leaks/DT in 4 patients (i.e. 1 cervical patient (2 EBP failed attempts), 3 lumbar patients (1 failed EBP)). Conclusion: Early direct surgical repair of recurrent postoperative spinal CSF leaks/DT remains the treatment of choice. Our literature review revealed 3 underpowered studies including just 20 patients where 20% of EBP failed to control recurrent postoperative fistulas (range of failure from 0-60% per study). Although there are likely other studies we failed to identify in this review, they too are likely insufficiently powered to document significant efficacy for performing EBP over direct surgical repair for recurrent postoperative CSF leaks/DT.

Why are spine surgeons sued, and with what outcomes?

Background: Why are spine surgeons sued, how successfully, and for how much? Typical bases for spinal medicolegal suits have included; the failure to timely diagnose and treat, surgical negligence, (i.e. especially resulting in significant neurological deficits), and the lack of informed consent. We reviewed 17 medicolegal spinal articles looking for additional reasons for suits, along with identifying other factors contributing to defense verdicts, plaintiffs' verdicts, or settlements. Methods: After confirming the same three most likely causes of medicolegal suits, other factors leading to such suits included; the lack of patient access to surgeons postoperatively, poor postoperative management (i.e. contributing to new postoperative neurological deficits), failure to communicate between specialists/surgeons perioperatively, and failure to brace. Results: Critical factors leading to more plaintiffs' verdicts and settlements along with higher payouts for both included new severe and/or catastrophic postoperative neurological deficits. Conversely, defense verdicts were more likely for those with less severe new and/or residual injuries. The total number of plaintiffs' verdicts ranged from 17-35.2%, settlements, from 8.3-37%, and defense verdicts from 27.7-75%. Conclusion: The three most frequent bases for spinal medicolegal suits continue to include; failure to timely diagnose/treat, surgical negligence, and lack of informed consent. Here, we identified the following additional causes of such suits; the lack of patient access to surgeons perioperatively, poor postoperative management, lack of specialist/surgeon communication, and failure to brace. Further, more plaintiffs' verdicts or settlements and greater respective payouts were observed for those with new and/or more severe/catastrophic deficits, while more defense verdicts were typically rendered for patients with lesser new neurological injuries.

Public Librarian Perceptions of Assisting Immigrant Patrons: Results from a Multi-State Survey.

Public libraries in the United States (U.S.) are important sources of health information. Immigrants comprise a large portion of the U.S. population, and research suggests that public libraries help immigrants adjust to life in a new country. Public libraries help immigrants access information directly related to health and provide programs that have indirect impacts on health outcomes, including learning a new language and forging social ties. The purpose of this paper was to examine perspectives from librarians related to interactions with immigrant patrons and how their library supports them in this role. Public librarians (n = 205) from two selected U.S. states completed an online survey focusing on how comfortable they were in helping immigrants with inquiries related to health and the role of the public library in supporting librarians in this endeavor. Respondents generally reported high levels of comfort interacting with immigrants, although there was limited interaction on potentially sensitive topics (i.e., immigration, health). Library staff perceived that libraries overall were not effective in meeting the needs of immigrant populations and that librarians were infrequently offered professional training related to cultural competency and diversity. The findings echo previous studies that demonstrate the need for professional development to ensure that librarians are aware of library resources available to assist immigrant patrons. Findings from this study suggest opportunities for public health professionals and public librarians to collaborate to ensure the provision of reliable resources, health information, and referrals to community-based services.

Perspective: Lumbar adhesive arachnoiditis (AA)/ Chronic AA (CAA) are clinical diagnoses that do not require radiographic confirmation.

Background: Our hypothesis was that lumbar adhesive arachnoiditis (AA)/chronic lumbar AA (CAA) are clinical diagnoses that do not require radiographic confirmation. Therefore, patients with these syndromes do not necessarily have to demonstrate significant radiographic abnormalities on myelograms, MyeloCT studies, and/or MR examinations. When present, typical AA/CAA findings may include; central or peripheral nerve root/cauda equina thickening/clumping (i.e. latter empty sac sign), arachnoid cysts, soft tissue masses in the subarachnoid space, and/or failure of nerve roots to migrate ventrally on prone MR/Myelo-CT studies. Methods: We reviewed 3 articles and 7 clinical series that involved a total of 253 patients with AA/CAA to determine whether there was a significant correlation between these clinical syndromes, and myelographic, Myelo-CT, and/or MR imaging pathology. Results: We determined that patients with the clinical diagnoses of AA/CAA do not necessarily exhibit associated radiographic abnormalities. However, a subset of patients with AA/CAA may show the classical AA/CAA findings of; central or peripheral nerve root/cauda equina thickening/clumping (empty sac sign), arachnoid cysts, soft tissue masses in the subarachnoid space, and/or failure of nerve roots to migrate ventrally on prone MR/ Myelo-CT studies. Conclusion: Patients with clinical diagnoses of AA/CAA do not necessary show associated neuroradiagnostic abnormalities on myelograms, Myelo-CT studies, or MR. Rather, the clinical syndromes of AA/CAA may exist alone without the requirement for radiolographic confirmation.

Short Review/Perspective on Adjacent Segment Disease (ASD) Following Cervical Fusion Versus Arthroplasty.

Background: Although the incidence of radiographic Adjacent Segment Disease (ASD) following anterior cervical diskectomy/fusion (ACDF) or cervical disc arthroplasty (CDA) typically ranges from 2-4%/year, reportedly fewer patients are symptomatic, and even fewer require secondary surgery. Methods: Multiple studies have documented a 2-4% incidence of radiographic ASD following either ACDF or CDA per year. However, fewer are symptomatic from ASD, and even fewer require additional surgery/reoperations. Results: In a meta-analysis (2016) involving 83 papers, the incidence of radiographic ASD per year was 2.79%, but symptomatic disease was present in just 1.43% of patients with only 0.24% requiring secondary surgery. In another study (2019) involving 38,149 patients undergoing ACDF, 2.9% (1092 patients; 0.62% per year) had radiographic ASD within an average of 4.66 postoperative years; the younger the patient at the index surgery, the higher the reoperation rate (i.e. < 40 years of age 4.56 X reoperations vs. <70 at 2.1 X reoperations). In a meta-analysis of 32 articles focusing on ASD 12-24 months following CDA, adjacent segment degeneration (ASDeg) occurred in 5.15% of patients, but adjacent segment disease (AS Dis) was noted in just 0.2%/ year. Further, AS degeneration occurred in 7.4% of patients after 1-level vs. 15.6% following 2 level fusions, confirming that CDA's "motion-sparing" design did not produce the "anticipated" beneficial results. Conclusion: The incidence of radiographic ASD ranges from 2-4% per year for ACDF and CDA. Additionally, both demonstrate lesser frequencies of symptomatic ASD, and the need for secondary surgery. Further, doubling the frequency of ASD following 2 vs. 1-level CDA, should prompt surgeons to limit surgery to only essential levels.