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: 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: 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: 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.

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.

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.

Cervical disc arthroplasty (CDA)/total disc replacement (TDR) vs. anterior cervical diskectomy/fusion (ACDF): A review

Background

We performed a focused review to determine the "non-inferiority", potential superiority, and relative safety/efficacy for performing cervical disc arthroplasty (CDA)/total disc replacement (TDR) in carefully selected patients vs. anterior cervical diskectomy/fusion (ACDF). Notably, CDA/TDR were devised to preserve adjacent level range of motion (ROM), reduce the incidence of adjacent segment degeneration (ASD), and the need for secondary ASD surgery.

Methods

We compared the incidence of ASD, reoperations for ASD, safety/efficacy, and outcomes for cervical CDA/TDR vs. ACDF. Indications, based upon the North American Spine Society (NASS) Coverage Policy Recommendations (Cervical Artificial Disc Replacement Revised 11/2015 and other studies) included the presence of radiculopathy or myelopathy/myeloradiculopathy at 1-2 levels between C3-C7 with/without neck pain. Contraindications for CDA/TDR procedures as quoted from the NASS Recommendations (i.e. cited above) included the presence of; "Infection…", "Osteoporosis and Osteopenia", "Instability…", "Sensitivity or Allergy to Implant Materials", "Severe Spondylosis…", "Severe Facet Joint Arthropathy…", "Ankylosing Spondylitis" (AS), "Rheumatoid Arthritis (RA), Previous Fracture…", "Ossification of the Posterior Longitudinal Ligament (OPLL)", and "Malignancy…". Other sources also included spinal stenosis and scoliosis.

Results

Cervical CDA/TDR studies in the appropriately selected patient population showed no inferiority/ occasionally superiority, reduced the incidence of ASD/need for secondary ASD surgery, and demonstrated comparable safety/efficacy vs. ACDF.

Conclusion

Cervical CDA/TDR studies performed in appropriately selected patients showed a "lack of inferiority", occasional superiority, a reduction in the incidence of ASD, and ASD reoperation rates, plus comparable safety/efficacy vs. ACDF.

Review of anterior cervical diskectomy/fusion (ACDF) using different polyetheretherketone (PEEK) cages

Background

Multiple anterior cervical diskectomy/fusion (ACDF) techniques now use a variety of Polyehteretherketone (PEEK) cages; stand-alone (SA) and zero-profile (ZP) with/without screws, cages filled with demineralized bone matrix/autograft, and cages coated with hydroxyapatite or titanium. We compared the safety/ efficacy between different PEEK ACDF cage constructs in 17 studies, and in some cases, additionally contrasted results with "routine" ACDF (i.e. series/historical data performed with combinations of iliac autograft/allograft and plates).

Methods

We focused on the clinical outcomes, fusion rates, postoperative radiographic changes/lordosis/ subsidence, and/or reoperation rates for various PEEK ACDF constructs vs. "routine" ACDF.

Results

One to 3 and 4-level PEEK ACDF cages demonstrated high fusion rates, few cage failures, and low reoperation rates. Subsidence for PEEK ACDF cages did not reduce fusion rates or diminish the quality of postoperative outcomes. Further, titanium-coated (T-C) PEEK cages lowered fusion rates in one study (i.e. 44.1% fusions vs. 88.2% for routine PEEK ACDF) while ACDF PEEK cages coated with hydroxyapatite (HA) showed only a "trend" toward enhanced arthrodesis.

Conclusion

One to 3-4 multilevel ACDF PEEK cage constructs demonstrated comparable safety/efficacy when compared with each other, or in select cases, with "routine" ACDF (i.e. using autograft/allograft and plates).

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.

Review/perspective on hysterical paralysis: A diagnosis of exclusion for spinal surgeons

Background:

Hysterical paralysis (HP) and/or conversion disorders (CD) are diagnoses of exclusion for spine surgeons. Before assigning this diagnosis to a patient, they must first undergo a full neurodiagnostic evaluation (i.e., X-rays, MR, CT/Myelo-CT) to rule out organic spinal pathology. Here, we reviewed select articles highlighting how to differentiate HP/CD patients from those with spinal disease.

Methods:

Several case studies and small series of patients with HP/CD were included in our analysis. Notably, prior to being assigned the diagnoses of HP/CD, patients had to first undergo X-ray, MR, CT, and/or Myelo-CT evaluations to rule out spinal disorders; typically, their neurodiagnostic studies were normal.

Results:

Patients with HP/CD often presented with varying clinical complaints of motor paralysis despite intact reflexes, normal sensory examinations, and lack of sphincter disturbance (i.e. intact rectal tone). Further, go and nogo functional MRI (fMRI) examinations demonstrated inconsistencies in areas of brain activation for patients with HP/CD complaints.

Conclusions:

HP/CD are diagnoses of exclusion, and patients should first undergo a full panel of neurodiagnostic studies to rule out organic spinal disease. While those with HP/CD should not have unnecessary operations, those with real “surgical pathology” should have appropriate spine surgery performed in a timely fashion.

Review/Perspective: Operations for Cauda Equina Syndromes - “The Sooner the Better”

Background:

Although most studies recommended that early surgery for cauda equina syndromes (CES) be performed within <48 h., the largest and most comprehensive Nationwide Inpatient Sample Database (NISC) series, involving over 25,000 CES patients recommended that time be shortened to 0–<24 h. In short, CES surgery performed “the sooner the better,” was best.

Methods:

The 2 major variants of CES include; incomplete/partial ICES, and those with urinary retention/bowel incontinence (RCES). Those with ICES often exhibit varying combinations of motor weakness, sensory loss (i.e. including perineal numbness), and urinary dysfunction, while RCES patients typically exhibit more severe paraparesis, sensory loss including saddle anesthesia, and urinary/bowel incontinence. The pathology responsible for ICES/RCES syndromes may include; acute disc herniations/stenosis, trauma (i.e. including iatrogenic/ surgical hematomas etc.), infections, abscesses, and other pathology. Surgery for either ICES/RCES may include decompressions to multilevel laminectomies/fusions.

Results:

Following early surgery, most studies showed that ICES and RCES patients exhibited improvement in motor weakness and sensory loss. However, recovery of sphincter function was more variable, being poorer for RCES patients with preoperative urinary retention/bowel incontinence.

Conclusions:

Although early CES surgery was defined in most studies as <48 h., two large NISC series involving over 25, 000 CES patients showed that CES surgery performed within 0 -< 24 h resulted in the best outcomes.

Review/Perspective On the Diagnosis and Surgical Management of Spinal Arachnoid Cysts

Background:

Spinal arachnoid cysts (SAC) are typically congenital, spontaneous, traumatic (i.e., including iatrogenic/surgical), or inflammatory in origin. In descending order, they occur in the thoracic, lumbar, and cervical spine, and originate from focal entrapment of the arachnoid membrane. Arachnoid cysts represent 1–2% of all cystic spinal masses/tumors. The majority are extradural arachnoid cysts (EDAC) while 10% of all arachnoid cysts are intradural (IDAC) including subarachnoid, or extra-arachnoidal/subdural. Only rarely are they intramedullary in location. The clinical symptoms/signs of IDAC/EDAC include; intracranial hypotension (i.e., due to continued cerebrospinal fluid drainage), radiculopathy, and/or myelopathy.

Methods:

Magnetic Resonance Images (MR) and Myelo-Computed Tomography (Myelo-CT) studies classically document the predominant dorsal location of IDAC/EDAC. They also show their extent and severity contributing to root, cord, and/or cauda equina compression. In the cervical/thoracic spine, MR/Myelo-CT studies classically show the “double cord” or “windsock” signs, while the “fake arachnoiditis sign” may be seen in the lumbar spine. The latter sign signals the presence of a circumferential extra-arachnoidal-subdural cyst that centrally “traps” the cauda equina. Note, that this resembles and is often misinterpreted as adhesive archnoiditis.

Results:

Patients with significant SAC-related neurological deficits typically warrant early surgery. That surgery includes; partial/total resection/fenestration of cyst walls, and occlusion of communicating fistulas with or without accompanying shunts.

Conclusion:

It is critical to recognize the clinical (i.e., intracranial hypotension, radiculopathy, and/or myelopathy) and radiographic MR/Myelo-CT signs (i.e., “double cord,” “windsock signs”, or “fake arachnoiditis sign”) of IDAC, EDAC, or intramedullary spinal arachnoid cysts to appropriately offer treatment. For those with significant neurological deficits, early surgery (i.e. optimally 0-< 24 hours after the onset of symptoms/signs consisting of laminectomies, partial/total cyst resection/fenestration, and ligation/occlusion of the subarachnoid-cyst fistula with or without shunt placement), is essential to avoid significant permanent neurological sequelae.

Perspective on the true incidence of bowel perforations occurring with extreme lateral lumbar interbody fusions. How should they be treated?

Background

What is the risk of bowel perforation (BP) with open or minimally invasive (MI) extreme lateral lumbar interbody fusion (XLIF)? What is the truth? Further, if peritoneal symptoms/signs arise following XLIF/MI XLIF, it is critical to obtain an emergent consultation with general surgery who can diagnose and treat a potential BP.

Literature Review

In multiple series, the frequency of BP ranged markedly from 0.03% (i.e. 1 of 2998 patients), to 0.08% (11/13,004), to 0.5%, to 8.3% (1 in 12 patients), up to 12.5% (1 in 8 patients). BPs attributed to different causes carry high mortality rates varying from 11.1% to 23%. For the 11 (0.08%) BP occurring out of 13,004 patients undergoing XLIF in one series, there was one (9.09%) death due to uncontrolled sepsis. In another series, where 31 BP were identified for multiple lumbar surgical procedures identified through PubMed (1960-2016), including 10 (32.2%) for lateral lumbar surgery including XLIF, the overall mortality rate was 12.9% (4/31).

Conclusion

The incidence of BPs occurring following XLIF/MI XLIF procedures ranged from 0.03% to 12.5% in various reports. What is the true incidence of these errors? Certainly, it is more critical that when spine surgeons' patients develop acute peritoneal symptoms/signs following these procedures, they immediately consult general surgery to both diagnose, and treat potential BP in a timely fashion to avoid the high morbidity (87.1%) and mortality rates (12.9%) attributed to these perforations.

Perspective on robotic spine surgery: Who's doing the thinking?

Background

Robotic assisted (RA) spine surgery was developed to reduce the morbidity for misplaced thoracolumbar (TL) pedicle screws (PS) resulting in neurovascular injuries, dural fistulas, and/or visceral/other injuries. RA is gaining the attention of spine surgeons to optimize the placement of TL PSs, and to do this more safely/effectively versus utilizing stereotactic navigation alone, or predominantly free hand (FH) techniques. However, little attention is being focused on whether a significant number of these TL RA instrumented fusions are necessary.

Methods

RA spine surgery has been developed to improve the safety, efficacy, and accuracy of minimally invasive TL versus open FH PS placement.

Results

Theoretical benefits of RA spine surgery include; enhanced accuracy of screw placement, fewer complications, less radiation exposure, smaller incisions, to minimize blood loss, reduce infection rates, shorten operative times, reduce postoperative recovery periods, and shorten lengths of stay. Cons of RA include; increased cost, increased morbidity with steep learning curves, robotic failures of registration, more soft tissue injuries, lateral skiving of drill guides, displacement of robotic arms impacting accurate PS placement, higher reoperation rates, and potential loss of accuracy with motion versus FH techniques. Notably, insufficient attention has been focused on the necessity for performing many of these TL PS instrumented fusions in the first place.

Conclusion

RA spinal surgery is still in its infancy, and comparison of RA versus FH techniques for TL PS placement demonstrates several potential pros, but also multiple cons. Further, more attention must be focused on whether many of these TL PS instrumented procedures are even warranted.

Medicolegal corner (spine): Contraindicated use of DuraSeal in anterior cervical spine led to quadriplegia

Background:

The package insert for DuraSeal (Integra LifeSciences, Princeton NJ) states it is Contraindicated for use in the anterior cervical spine (confined space): “Do not apply DuraSeal® hydrogel to confined bony structures where nerves are present since neural compression may result due to hydrogel swelling (…up to 12% of its size in any direction).” Further, it should not be used to treat massive unrepaired cerebrospinal fluid (CSF) leaks in any location; “…(it) is indicated as an adjunct to sutured dural repair during spine surgery to provide watertight closure,” but it is not to be used “...for a gap greater than 2 mm….”

Methods:

A spinal surgeon interpreted a geriatric patient’s MR as showing severe C3-C4 to C5-C6 anterior cord compression due to disc disease/spondylosis. However, he never reviewed the CT report/images that documented marked ossification of the posterior longitudinal ligament (OPLL) with multiple signs of dural penetrance.

Results:

The anterior C4, C5 corpectomy, and C3-C6 strut fusion/plating resulted in a massive, irreparable cerebrospinal fluid (CSF) leak. Despite the contraindications, the surgeon mistakenly applied DuraSeal which caused the patient’s postoperative quadriplegia (i.e., as documented on the delayed postoperative MR scan). Following a secondary surgery consisting of a laminectomy/posterior fusion, the patient was still quadriplegic. Further, as he requested no postoperative MR scan and performed no subsequent corrective surgery (i.e., anterior removal of DuraSeal), the patient remained permanently quadriplegic.

Conclusion:

DuraSeal is directly contraindicated for use in the anterior cervical spine, with/without a CSF leak. Here, utilizing DuraSeal for anterior cervical OPLL surgery resulted in permanent quadriplegia, and was below the standard of care.

Review: Perspective on ocular toxicity of presurgical skin preparations utilizing Chlorhexidine Gluconate/Hibiclens/Chloraprep

Background:

Chlorhexidine Gluconate (CHG), Hibiclens (4% CHG with 4% Isopropyl Alcohol Detergent), and Chloraprep (i.e. labeled CHG-based solutions), utilized as preoperative surgical preparatory solutions may all cause severe oculotoxicity and ototoxicity. Alternatively, 10% Povidone-Iodine (PI) solutions without detergent demonstrate minimal toxic effects on the eyes and ears.

Methods:

Based on studies from 1984 to 2021, we compared the safety/efficacy of CHG-based versus PI-based solutions utilized for presurgical skin preparation near the cornea/eyes and ears (i.e., predominantly for cranial or cervical spine surgery).

Results:

Some studies documented that even minimal exposure (i.e., “splash risk”) during face/neck skin preparation with CHG-based solutions could result in irreversible corneal injury and ototoxicity. Within minutes to hours, CHG-based non-detergent solutions posed the risks of; corneal epithelial edema, anterior stromal edema, conjunctival chemosis, bullous keratopathy, and de-epithelialization. Notably, even occlusive dressings like Tegaderm could not protect against CHG penetration. Alternatively, PI-based solutions posed no to minimal ocular and/or ototoxicity, while often demonstrating comparable protection against surgical site infections (SSI).

Conclusion:

Chlorhexidine Gluconate (CHG), Hibiclens, and Chloraprep (i.e. CHG-based solutions) are often used as skin preparations near the face/eyes/spine (i.e., particularly anterior/posterior cervical procedures). However, if these solutions come in contact with the eyes, corneal irritation, abrasions, and even blindness may result. Alternatively, PI non-detergent solutions demonstrate safety/minimal oculotoxicity/ototoxicity, while frequently showing comparable efficacy against SSI.

Perspective: Early diagnosis and treatment of postoperative recurrent cerebrospinal fluid fistulas/ dural tears to avoid adhesive arachnoiditis

Background:

Intraoperative traumatic cerebrospinal fluid (CSF) fistulas/dural tears (DT) occur in up to 8.7–9.5% of primary lumbar surgical procedures. Further, they recur secondarily in between 8.1% and 17% of cases. It is critical to diagnose and treat these recurrent lumbar DT early (i.e. within 3–4 weeks of the index surgery) to avoid the evolution of adhesive arachnoiditis (AA), and its’ permanent neurological sequelae.

Methods:

Postoperative lumbar CSF fistulas/DT should be diagnosed on postoperative MR scans, and confirmed on Myelo-CT studies if needed. They should be definitively treated/occluded early on (e.g. within 3–4 postoperative weeks) to avoid the evolution of AA which can be readily diagnosed on MR studies, and corroborated, if warranted, on Myelo-CT examinations. The most prominent MR/Myelo-CT findings include; nerve roots aggregated in the central thecal sac, nerve roots peripherally scarred/adherent to the surrrounding meningeal wall (“empty thecal sac sign”), soft tissue masses in the subarachnoid space, and/or multiple loculated/scarred compartments.

Results:

Percutaneous interventional procedures (i.e. epidural blood patches, injection of fibrin glue (FG)/fibrin sealants (FS)) are rarely effective for treating postoperative recurrent lumbar CSF fistulas. Rather, direct surgical occlusion is frequently warranted including the use of; an operating microscope, adequate surgical exposure, 7-0 Gore-Tex sutures, muscle/dural patch grafts or suture anchors, followed by the application of microfibrillar collagen, and fibrin sealant/glue.

Conclusion:

Lumbar AA most commonly results from the early failure to diagnose and treat recurrent postoperative CSF fistulas. Since the clinical course of lumbar AA is typically one of progressive neurological deterioration, avoiding its’ initial onset is key.

MEDICOLEGAL CORNER. Failure to replace obstructed lumbar drain after thoracic-abdominal aortic aneurysm repair leads to paraplegia

Background

To avoid spinal cord ischemia following endovascular/open thoracic-abdominal aortic aneurysm (T-AAA) repair, lumbar drains (LDs) are placed to reduce intraspinal pressure, and increase spinal perfusion pressure. Here, we present a medicolegal case in which a critical care (CC) physician knew that the LD was obstructed following a T-AAA repair, but did not replace it until the patient became paraplegic. The patient was left with permanent sphincter loss, and a severe paraparesis.

Methods

A geriatric patient with multiple medical/cardiovascular comorbidities first underwent an endovascular T-AAA (Crawford Type II T-AAA) repair several years ago. Due to continued expansion of the aneurysm, the patient now required an open T-AAA repair.

Results

Prior to the open T-AAA surgery, a prophylactic LD was placed. Postoperatively, the patient required a second emergency operation to repair a leaking intercostal artery anastomosis. The next morning, the CC physician clearly documented the drain was obstructed, but chose to follow the patient; 3.5 hours later, the patient became paraplegic. The LD was replaced after the patient was first sent to MRI to rule out a spinal cord hematoma, resulting in a total delay of more than 6.5 h from when the CC physician first became aware of the non-functioning LD. The patient later regained only partial function, remaining significantly paraparetic with total loss of bowel/bladder function.

Conclusion

LD for endovascular/open T-AAA repairs reduce spinal fluid pressure, increase spinal cord perfusion pressures, and limits the frequency (i.e. 2.3-2.6%) of resultant spinal cord ischemia/paralysis. Here, despite the CC physician's failure to replace an obstructed LD after an open T-AAA, repair, the jury rendered a defense verdict.

Case of the week: Updating a cervical MR scan avoided unnecessary cervical surgery

Background:

As spinal surgeons, we have all likely seen cases in which lumbar disc herniations regressed/resolved on successive MR studies. Here, we present a patient whose original cervical MR showed a large C4-C5 cervical disc herniation that completely resolved on the follow-up MR obtained 9 months later, thus avoiding cervical surgery.

Case Description:

A young patient (e.g. <30 years old) sustained multiple prior traumatic events over the past 3 years. The last episode 9 months ago resulted in the performance of an MR scan that demonstrated a significant central C4-C5 disc herniation with cord/root compression. Despite pain and mild radiculopathy, the patient had no focal neurological deficit, and did not undergo surgery. When the patient recently consulted multiple spinal orthopedists and neurosurgeons, the uniform recommendation was for a C4-C5 anterior cervical discectomy/ fusion (ACDF). However, a telemedicine consultation with a spinal neurosurgeon resulted in a follow-up cervical MR scan that demonstrated cervical disc resorption, and, therefore, no need for cervical surgical intervention. When the new study showed full resolution of the C4-C5 disc, the telemedicine and local neurosurgeon agreed that cervical surgery was unnecessary.

Conclusion:

The spinal literature shows that predominantly lumbar disc herniations (LDH) spontaneously regress on MR studies 34.7–95% of the time over 6–17 month intervals, with full resolution being seen in 43–75% of cases. As cervical disc herniations likely demonstrate similar resorption/resolution on successive MR studies, old cervical MR examinations should probably be updated/repeated in patients who are being considered for cervical surgical intervention. If/when cervical discs have resorbed, cervical surgery may be avoided.

Case report (precis): Atypical delayed presentation of cervical spinal epidural abscess

Background

Older patients with spinal epidural abscesses (SEA) may present in an atypical fashion, failing to exhibit the classical triad of pain, fever, and a neurological deficit. Rather, they may be less aware of pain, fail to develop a fever, and attribute their neurological deficit to "old age." Further, their laboratory studies may not be abnormal, and critical findings on MR (i.e., more so than CT studies) may be overlooked. Here, we present an elderly patient with severe upper extremity monoparesis whose cervical SEA was overlooked for months.

Case Description

Over 10 months, and 6 months ago respectively, the patient had two successive MR scans ordered due to falls; both were interpreted as normal. Within the past few months, a third cervical MR, and an initial CT scan were performed; they both showed "questionable" changes (e.g. cortical irregularity/epidural air) that were largely ignored. When the patient presented to a spine surgeon with severe upper extremity monoparesis, the fourth MR clearly demonstrated a high cervical SEA. Of interest, laboratory findings were normal (e.g. white blood cell count (WBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP)). The patient successfully underwent an anterior cervical discectomy/and fusion (ACDF); cultures grew Staphylococcus aureus, and he was appropriately managed with intravenous antibiotic therapy.

Conclusion

This case report (precis) highlights three "teaching" points. First, elderly immunologically compromised patients may not develop the classical SEA triad of pain, fever, and a neurological deficit. Second, laboratory studies may remain normal. Third, it may take longer for abnormal findings to develop on MR/CT studies consistent with SEA in immunocompromised older patients, thus resulting in very delayed surgery.

Reconstruction of Shattered Lumbo-Sacral Junction/Pelvis Utilizing Bilateral L4-Sacrum Fibula Strut Allograft And Double Iliac Screws Plus Routine Lumbar Pedicle Screw Fixation

Background:

A traumatically shattered lumbosacral junction/pelvis may be difficult to repair. Here the authors offer a pelvic fixation technique utilizing routine pedicle screws, interbody lumbar fusions, bilateral iliac screws/ rods/crosslinks, and bilateral fibular strut allografts from the lumbar spine to the sacrum.

Methods:

A middle aged male sustained a multiple storey fall resulting in a left sacral fracture, and right sacroiliac joint (SI) dislocation. The patient had previously undergone attempted decompressions with routine pedicle screw L4-S1 fusions at outside institutions; these failed twice. When the patient was finally seen, he exhibited, on CT reconstructed images, MR, and X-rays, a left sacral fracture nonunion, and a right sacroiliac joint dislocation.

Results:

The patient underwent a bilateral pelvic reconstruction utilizing right L4, L5, S1 and left L4, L5 pedicle screws plus interbody fusions (L4-L5, and L5, S1), performed from the left. Unique to this fusion construct was the placement of bilateral double iliac screws plus the application of bilateral fibula allografts from L4-sacrum filled with bone morphogenetic protein (BMP). After rod/screw/connectors were applied, bone graft was placed over the fusion construct, including the decorticated edges of the left sacral fractures, and right SI joint dislocation. We additionally reviewed other pelvic fusion reconstruction methods.

Conclusions:

Here, we utilized a unique pelvic reconstruction technique utilizing pedicle screws/rods, double iliac screws/rods, and bilateral fibula strut grafts extending from the L4-sacrum filled with BMP.

Case Report (Precis): Patient with MR-Documented Large Lateral Cervical Disc Misdiagnosed as Neurodegenerative Disease

Background:

Patients who present to neurologists with cervical radiculopathy typically undergo initial MR scans. If reports show “abnormal” findings they, and other physicians, should review the studies with the interpreting radiologists/neuroradiologists. When patients’ neurological deficits progress, neurologists should review their electromyographic (EMG) findings (i.e. especially if documenting neurodegenerative disease), the initial “abnormal” MR scans/reports (i.e. review with radiologists/neuroradiologists), and obtain spinal surgical consultations to rule out “surgical” disease.

Case Description:

A middle aged patient presented several months previously to a neurologist with the chief complaint of unilateral neck/arm pain, accompanied by focal weakness, and numbness in a specific distal cervical nerve root distribution. The patient’s initial MR showed a large lateral disc herniation in the lower cervical spine on the symptomatic side. However, as the neurologist interpreted the EMG as consistent with a neurodegenerative syndrome, the patient was not referred to a spine specialist. Frustrated by progressive worsening, the patient ultimately referred himself for a spinal surgical consultation. By this time, he had developed severe unilateral upper extremity motor weakness (3/5), pin loss, atrophy, and fasciculations in the nerve root distribution that correlated with the location of the distal cervical disc seen on the original MR. When the repeat MR confirmed the same large distal lateral disc herniation, the patient successfully underwent an anterior cervical discectomy/fusion (ACDF).

Conclusion:

This Case Report (Precis) highlights two “teachable moments”. First, physicians, including neurologists and spinal surgeons, who order MR studies that show “abnormal” findings should review these studies with the interpreting radiologists/neuroradiologists. This is particuarly true if patients continue to demonstrate progressive neurological deterioration. Second, before patients are told that they have neurodegenerative syndormes, repeated review of the MR reports and/or repeating these studies, and obtaining spinal surgical consultations are warranted to rule out “surgical” disease.

Reperfusion Injury (RPI)/White Cord Syndrome (WCS) Due to Cervical Spine Surgery: A Diagnosis of Exclusion

Background:

Following acute cervical spinal cord decompression, a subset of patients may develop acute postoperative paralysis due to Reperfusion Injury (RPI)/White Cord Syndrome (WCS). Pathophysiologically, this occurs due to the immediate restoration of normal blood flow to previously markedly compressed, and under-perfused/ischemic cord tissues. On emergent postoperative MR scans, the classical findings for RPI/ WCS include new or expanded, and focal or diffuse intramedullary hyperintense cord signals consistent with edema/ischemia, swelling, and/or intrinsic hematoma. To confirm RPI/WCS, MR studies must exclude extrinsic cord pathology (e.g. extramedullary hematomas, new/residual compressive disease, new graft/vertebral fracture etc.) that may warrant additional cervical surgery to avoid permanent neurological sequelae.

Methods:

In the English literature (i.e. excluding 2 Japanese studies), 9 patients were identified with postoperative RPI/WCS following cervical surgical procedures. For 7 patients, new acute postoperative neurological deficits were appropriately attributed to MR-documented RPI/WCS syndromes (i.e. hyperintense cord signals). However, for 2 patients who neurologically worsened, MR studies demonstrated residual extrinsic disease (e.g. stenosis and OPLL) warranting additional surgery; therefore, these 2 patients did not meet the criteria for RPI/WCS.

Results:

The diagnosis of RPI/WCS is one of exclusion. It is critical to rule out residual extrinsic cord compression where secondary surgery may improve/resolve neurological deficits.

Conclusions:

Patients with acute postoperative neurological deficits following cervical spine surgery must undergo MR studies to rule out extrinsic cord pathology before being diagnosed with RPI/WCS. Notably, 2 of the 9 cases of RPI/WCS reported in the literature required additional surgery to address stenosis and OPLL, and therefore, did not have the RPI/WCS syndromes.

Case Report (Precis): Two Telemedicine Consultants Miss Foot Drop: When To See Patients in Person

Background

Telemedicine has been rapidly adopted due to COVID-19. In the earliest days, most screenings were performed by primary care/internal medicine consultants; referrals to subspecialists were minimized. Now, as the pandemic has evolved over 6 months, secondary telemedicine consultations should be limited, and earlier involvement of appropriate subspecialists should be reconsidered to optimize patient management.

Case Description

An older individual spoke to an on-call general medical physician with the chief complaint of the acute onset of low back pain after moderately strenuous activity, with severe unilateral radiculopathy. The telemedicine physician recommended a non-steroidal. anti-inflammatory agent without any specific recommendations regarding follow-up. A few days later, with progression of unilateral pain and numbness, a second telemedicine medical consultation was performed; a Medrol dose pack and muscle relaxant were now recommended, again without any follow-up recommendations. Days later, with increased unilateral pain/ near anesthesia in the foot, the patient was seen by a spinal surgeon who found; unilateral SLR positive at 20 degrees, a 0/5 foot drop, loss of the Achilles Response, and decreased pin appreciation in the L5 distribution. The patient's emergent lumbar MR showed a large unilateral disc herniation with inferior migration at the appropriate level, warranting surgical consideration.

Conclusion

Here, we emphasized several points. First, telemedicine may be adequate for the initial screening, but further complaints would be better evaluated in person by either a medical or surgical subspecialist; here, both could have recognized the very clear unilateral foot drop. Second, the patient should have had a scheduled follow-up in-person consultation. Third, appropriate diagnostic studies should have been ordered at the time of the second telemedicine consultation to establish the correct diagnosis and direct treatment.

Unique Bone Suture Anchor Repair of Complex Lumbar Cerebrospinal Fluid Fistulas

Background

Spine surgeons encounter occasional complex cerebrospinal fluid fistulas/dural tears (CSF/DT) during lumbar spinal surgery. In some cases, these leaks are found during the index procedure, but others may appear postoperatively, or in the course of successive procedures. Here we asked, whether these complex CSF fistulas/DT could be more readily repaired utilizing a "bone suture anchor" technique, particularly where there is no residual dural margin/remnant.

Methods

With the combined expertise of the orthopedist and neurosurgeon, mini/micro bone suture anchors, largely developed for hand surgery, facilitated repair of complex DT occurring during lumbar spine surgery. This technique was utilized to suture in place fascia, periosteal, or muscle grafts, and was followed by the application of microfibrillar collagen, and a fibrin sealant.

Results

This mini/micro suture anchor technique has now been utilized to repair multiple significant intraoperative and/or postoperative recurrent DT, largely avoiding the need to place lumbar drains and/or lumbo- peritoneal shunts.

Conclusions

Here, we reviewed how to directly suture dural grafts utilizing a mini/micro bone suture anchor technique to repair complex intraoperative primary/recurrent DT occurring during lumbar spine surgery. The major advantages of this technique, in addition to obtaining definitive occlusion of the DT, largely avoids the need to place lumbar drains and/or lumbo-peritoneal shunts with their attendant risks and complications.

Incidence of Major Vascular Injuries with Extreme Lateral Interbody Fusion (XLIF)

Background:

Extreme lateral interbody fusions (XLIF) and minimally invasive (MI) XLIF theoretically offer wide access to the lumbar disc space. The theoretical advantages of XLIF include; minimally disturbing surrounding structures (e.g. neural, vascular, soft-tissue), while offering stability. In addition to the well-known increased frequency of neurological deficits attributed to XLIF, here we explored how often major vascular injures occur with XLIF/MI XLIF procedures.

Methods:

In 13 XLIF/MI XLIF studies, we evaluated the frequency of major vascular injuries.

Results:

The studies citing the different frequencies of vascular injuries associated with XLIF/MI XLIF were broken down into three categories. Of the 5 small and larger case series, involving a total of 6,732 patients (e.g. range of 12 to 4,607 patients/study), the incidence of vascular injuries ranged from 0% (3 studies) up to 0.4%. Three case reports presented major vascular injuries attributed to XLIF/MI XLIF. Two involved the L4-L5 level. The three complications included: one fatal injury, one, a retroperitoneal hematoma with hemorrhagic shock, and one major vascular injury. For the 5 review articles, major vascular complications were just discussed in 2, one study cited 3 specific major vascular injuries (e.g. 1 fatal, 1 life threating, and 1 lumbar artery pseudoaneurysm requiring embolization), while 2 other studies stated the frequency of these injuries was 0.4% for XLIF, and 1.7 % for OLIF (Oblique Lumbar Interbody Fusion).

Conclusions:

According to 5 small and larger case series, 3 case reports, and 5 review articles, the incidence of major vascular injuries occurring during XLIF/MI XLIF ranges from 0 to 0.03% to 0.4%.

What Can Spine Surgeons Do to Improve Patient Care and Avoid Medical Negligence Suits?

Background:

Why do patients sue following spine surgery? Here we reviewed some of the most frequent reasons for medical negligence suits against surgeons, adjunctive medical personnel, and or institutions/hospitals.

Methods:

Summarizing the multiple reasons for suits against spine surgeons, their colleagues/consultants, and hospitals should help surgeons identify the problems leading to suits, and improve patient care.

Results:

Several of the most common reasons for medical negligence suits include: lack of informed consent, ghost surgery, failure to diagnose and treat (e.g. including preoperative, perioperative, and post-surgical complications), performing unnecessarily risky, excessive and/or unnecessary surgery; failure to provide adequate postoperative care; absent or inadequate intraoperative neural physiological monitoring; and spoliation (e.g. fraudulent surgical, office, and/or hospital notes/records).

Conclusions:

There are many reasons why patients sue their spine surgeons. Being aware of the factors that lead to suits, spine surgeons should learn to provide better preoperative, intraoperative, and postoperative care, and, thus, limit perioperative morbidity and mortality.

Diagnosis and Safe Excision of Lumbar Synovial Cysts and Accompanying Pathology: A Perspective

Background:

Lumbar synovial cysts are often not sufficiently diagnosed prior to spine surgery. Utilizing both MR and CT studies is critical for recognizing the full extent/severity of these lesions.

Methods:

In patients with chronic, acute, or subacute lumbar disease, obtaining both MR and CT studies is critical to correctly diagnose; disc disease, hypertrophy/ossification of the yellow ligament (OYL), stenosis, with/without degenerative spondylolisthesis, and/or synovial cysts (SC).

Results:

MR T2 weighted images directly demonstrate hyperintensity within a SC. They initially cause lateral recess/caudad nerve root and/foraminal compromise, with larger extrusions causing significant lateral thecal sac, and far lateral/superior cephalad root compromise. CT 2 mm cuts often better demonstrate mid-vertebral level compression of cephalad nerve roots with/without SC calcification, along with the extent of mid-vertebral stenosis, hypertrophy/OYL, and DS. When CT studies directly document SC calcification, it alerts the surgeon to the increased potential risk of creating a cerebrospinal fluid fistula with full SC excision, and should prompt the adoption of alternative measures such as decompression/partial removal. Most critically, surgery for synovial cysts often warrants a 2-level laminectomy for fuller visualization of the cephalad and caudad nerve roots, and clearer differentiation of neural tissues from the large fibrotic SC capsule, to effect safer removal.

Conclusions:

Preoperatively, establishing the full cephalad and cauda extent of lumbar synovial cysts with both MR and CT studies is critical. Anticipation and better visualization of the foraminal/far lateral and superior extent of these lesions often warrants more extensive multilevel laminectomies for thecal sac and both cephalad and caudad root decompression.

Review of Risks and Complications of Extreme Lateral Interbody Fusion (XLIF)

Background

Extreme lateral interbody fusions (XLIF) and Minimally Invasive (MIS) XLIF were developed to limit the vascular injuries associated with anterior lumbar interbody fusion (ALIF), and minimize the muscular/ soft tissue trauma attributed to transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF), and posterolateral lumbar fusion (PLF).

Methods

Nevertheless, XLIF/MIS XLIF pose significant additional risks and complications that include; multiple nerve injuries (e.g. lumbar plexus, ilioinguinal, iliohypogastric, genitofemoral, lateral femoral cutaneous, and subcostals (to the anterior abdominal muscles: abdominal oblique), and sympathectomy), major vascular injuries, bowel perforations/postoperative ileus, seromas, pseudarthrosis, subsidence, and reoperations.

Results

The risks of neural injury with XLIF/MIS XLIF (up to 30-40%) are substantially higher than for TLIF, PLIF, PLF, and ALIF. These neural injuries included: lumbar plexus injuries (13.28%); new sensory deficits (0-75% (21.7%-40%); permanent 62.5%); motor deficits (0.7-33.6%-40%); iliopsoas weakness (9%-31%: permanent 5%), anterior thigh/groin pain (12.5-34%), and sympathectomy (4%-12%). Additional non-neurological complications included; subsidence (10.3%-13.8%), major vascular injuries (0.4%), bowel perforations, recurrent seroma, malpositioning of the XLIF cages, a 45% risk of cage-overhang, pseudarthrosis (7.5%), and failure to adequately decompress stenosis. In one study, reviewing 20 publications and involving 1080 XLIF patients, the authors observed "Most (XLIF) studies are limited by study design, sample size, and potential conflicts of interest."

Conclusion

Many new neurological deficits and other adverse events/complications are attributed to MIS XLIF/ XLIF. Shouldn't these significant risk factors be carefully taken into consideration before choosing to perform MIS XLIF/XLIF?

Many Intraoperative Monitoring Modalities Have Been Developed To Limit Injury During Extreme Lateral Interbody Fusion (XLIF/MIS XLIF): Does That Mean XLIF/MIS XLIF Are Unsafe?

Background:

Extreme lateral interbody fusions (XLIF) and Minimally Invasive (MIS) XLIF pose significant risks of neural injury to the; lumbar plexus, ilioinguinal, iliohypogastric, genitofemoral, lateral femoral cutaneous, and subcostal nerves. To limit these injuries, many intraoperative neural monitoring (IONM) modalities have been proposed.

Methods:

Multiple studies document various frequencies of neural injuries occurring during MIS XLIF/XLIF: plexus injuries (13.28%); sensory deficits (0-75%; permanent 62.5%); motor deficits (0.7-33.6%; most typically iliopsoas weakness (14.3%-31%)), and anterior thigh/groin pain (12.5-25%.-34%). To avoid/limit these injuries, multiple IONM techniques have been proposed. These include; using finger electrodes during operative dissection, employing motor evoked potentials (MEP), eliminating (no) muscle relaxants (NMR), and using “triggered” EMGs.

Results:

In one study, finger electrodes for XLIF at L4-L5 level for degenerative spondylolisthesis reduced transient postoperative neurological symptoms from 7 [38%] of 18 cases (e.g. without IONM) to 5 [14%] of 36 cases (with IONM). Two series showed that motor evoked potential monitoring (MEP) for XLIF reduced postoperative motor deficits; they, therefore, recommended their routine use for XLIF. Another study demonstrated that eliminating muscle relaxants during XLIF markedly reduced postoperative neurological deficits/thigh pain by allowing for better continuous EMG monitoring (e.g. NMR no muscle relaxants). Finally, a “triggered” EMG study” reduced postoperative motor neuropraxia, largely by limiting retraction time.

Conclusion:

Multiple studies have offered different IONM techniques to avert neurological injuries following MIS XLIF/XLIF. Does this mean that these procedures (e.g. XLIF/MIS XLIF) are unsafe?

Unnecessary Cervical Epidural Injection in An Octogenarian

Background:

Epidural spine injections (ESI) have no documented long-term efficacy. Furthermore, cervical ESI uniquely risk intramedullary injections with resultant neurological deficits (e.g. monoplegia to quadriplegia), and intravascular vertebral injections (e.g. which potentially contribute to stroke, brain stem infarction).

Case Description:

A patient in his mid-eighties presented with 1 year’s duration of neck pain without any accompanying numbness, tingling or weakness in the upper or lower extremities. He had no radiculopathy, myelopathy, or neurological deficit. Two years earlier, the patient sustained a myocardial infarction (MI), requiring over 5 stents and a defibrillator. At the time of presentation, he was still on a baby ASA (81 mg/day), on anti-hypertensives, and cholesterol-lowering medications. His non-contrast cervical CT scan (patient had a pacemaker/defibrillator and could not have an MR) from the summer of 2018 showed no significant spinal cord or nerve root compression at any level. Nevertheless, he was subjected to two cervical epidural injections in the early fall; his baby ASA was stopped 5 days prior to each of these injections. Notably, this placed him at increased risk of MI and/or stroke. When he was seen by neurosurgery, without any neurological deficit or significant cervical radiographic findings, he was referred back to neurology for continued conservative management.

Conclusions:

Patients are increasingly subjected to epidural cervical spinal injections that have no documented long-term efficacy, and expose them to significant risks/complications. This 80+ year-old patient, without a neurological deficit or significant cervical CT-documented pathology, underwent 2 cervical ESI that unnecessarily exposed him to potential cardiac-stent related thrombosis (e.g. stopping ASA for 5 days-a bona-fide requirement for ESI to avoid acute epidural hematomas).

When to stop anticoagulation, anti-platelet aggregates, and non-steroidal anti-inflammatories (NSAIDs) prior to spine surgery

Background

Based upon a select review of the literature, in my opinion, spine surgeons, not just our medical/cardiological colleagues, need to know when to stop anticoagulant, anti-platelet aggregates, and non-steroidal anti-inflammatory (NSAIDs) medications prior to spine surgery to avoid perioperative bleeding complications.

Methods

Typically, medical/cardiological consultants, who "clear our patients" are not as aware as we are of the increased risks of perioperative bleeding if anticoagulant, anti-platelet, and NSAIDs are not stopped in a timely fashion prior to spine surgery (e.g. excessive intraoperative hemorrhage, and postoperative seromas, hematomas, and wound dehiscence).

Results

Different medications need to be discontinued at varying intervals prior to spinal operations. The anticoagulants include; Warfarin (stop at least 5 preoperative days), and Xa inhibitors (Eliquis (Apixaban: stop for 2 days) and Xarelto (Rivaroxaban: stop for 3 days)); note presently data vary. The anti-platelet aggregates include: Aspirin/Clopidogrel (stop >7-10 days preoperatively). The multiple NSAIDs should be stopped for varying intervals ranging from 1-10 days prior to spine surgery, and increase bleeding risks when combined with any of the anticoagulants or anti-platelet aggregates. NSAIDs (generic name/commercial names should be stopped preoperatively for at least; 1 day- Diclofenac (Voltaran), Ibuprofen (Advil, Motrin), Ketorolac (Toradol); 2 days- Etodolac (Lodine), Indomethacin (Indocin); 4-days-Meloxicam (Mobic) and Naproxen (Aleve, Naprosyn, Anaprox); 4 days- Nabumetone (Relafen); 6 days - Oxaprozin (Daypro); and 10 days- Piroxicam (Feldene).

Conclusions

Spine surgeons need to know when anti-platelet, anticoagulant, and NSAIDs therapies should be stopped prior to spine surgery to avoid perioperative bleeding complications.

Case of the Week: Preoperative MR/CT Diagnosis of Left L2-L3 Disc Surgically Documented As Massive Synovial Cyst

Background:

The diagnosis of a lumbar herniated disc, stenosis, and other degenerative findings are typically established preoperatively with MR scans, supplemented with non-contrast CT studies. Here, a 77-year-old female, diagnosed as having L2-S1 stenosis and a large left-sided L2-L3 herniated disc was found at surgery to have a massive left-sided L2-L3 synovial cyst.

Case Description:

A 77-year-old female was followed by pain management for 6-months with proximal left lower extremity weakness. The lumbar MR at that time was read as demonstrating a large left L2-L3 disc herniation with inferior migration to the L3 mid pedicle level, accompanied by L2-S1 lumbar stenosis. When she finally consulted neurosurgery, she exhibited severe left iliopsoas and quadriceps weakness (2/5), absent lower extremity reflexes, and profound decreased pin appreciation in the left L2-L3 distributions. The repeat MR and new CT studies confimred a large left L2-L3 disc accompanied by moderate/marked L2-S1 stenosis. However, at surgery, consisting of a laminectomy L2-S1, the supposed left L2-L3 disc proved to be a massive synovial cyst. Postoperatively, the patient regained normal function, and remained neurologically intact 6 months later.

Conclusion:

In this 77 year-old female, the preoperative MR and CT scans were interpreted as showing a “typical” large left L2-L3 herniated disc. This proved at surgery to be a massive left L2-L3 synovial cyst. As demonstrated in this case, older patients with degenerative lumbar disease/stenosis, may have synovial cysts that mimic disc herniations both clinically and on preoperative diagnostic studies.

Review of Treatment Options for Smaller Benign Cranial Meningiomas: Observation, Stereotactic Radiosurgery, and Rarely, Open Surgery

Background:

MR/CT documented smaller cranial meningiomas in asymptomatic patients are often followed for years without requiring any intervention. Only a subset of patients who become symptomatic attributed to significant tumor growth, edema and/or mass effect may require stereotactic radiosurgery (SRS), and rarely, open surgery. Clearly, the decision for choosing any treatment modality must be made on a case by case basis and include an analysis of risks vs. benefits to the individual patient.

Methods:

Patients with smaller benign asymptomatic meningiomas are followed with sequential MR studies that typically document lack of tumor progression, edema, or mass effect. Those who become symptomatic with the typical triad (i.e. headaches, seizures, or visual loss) and other focal neurological deficits may warrant SRS, and only occasionally, open surgery. Surgery may indeed be warranted in the presence of certain mitigating factors, (e.g. young age, lesions located adjacent to by not yet invading critical structures etc.).

Results:

This review focused largely on smaller benign asymptomatic meningiomas. The non-operative/ conservative management vs. use of SRS vs. open surgery in select cases are discussed, along with a review of the morbidity/mortality of the respective interventions.

Conclusion:

There are multiple treatment options for patients with smaller asymptomatic cranial meningiomas. SRS may be warranted for those who exhibit tumor growth, increasing edema, and/or mass effect. Only rarely is open operative intervention necessary; this must include consideration of other factors that may warrant early surgery. Notably, the 5-year survival rates for SRS ranged from 95.2% - 97%, while the 10-year survival rates varied from 88.6% - 94%.