Failure of Surgical Equipoise in Posterior Cord Syndrome Myelopathy.

We suggest that a clinical diagnosis of posterior cord syndrome indicates primary posterior decompression in cervical spondylotic myelopathy cases. We present two unique cases of failed anterior decompression in neutrally aligned necks with compressive myelopathy and a literature review. Two recent cases of cervical spondylotic myelopathy that failed to respond after anterior surgical decompression and fusion surgery were observed at our institution. Both patients had motor strength preservation but were unable to stand and walk independently and had other clinical findings consistent with posterior cord syndrome rather than the more common anterior or central cord syndromes, and both responded well to staged posterior decompression. Posterior cervical decompression successfully relieved posterior cord syndrome symptoms after a failed anterior decompression in both of our cases. Posterior cord syndrome is a rare syndrome best diagnosed clinically and should be considered in cases of cervical spondylotic myelopathy in which motor strength testing is preserved.

Internal lumbar disc derangement with instability catch from monosegmental discopathy. The forgotten mechanical and kinetic surgical back pain syndrome.

STUDY DESIGN: This is a retrospective cohort experience reported with concurrent survey PROM outcomes. OBJECTIVE: To describe the results of open PLIF reconstruction for a select group of mechanical back pain patients who have mono- or bi-segmental discopathy on MRI imaging, a clinical history of repeated severe and disabling acute mechanical back pain symptoms, and the irregular lumbar motion pattern in returning erect from the flexed position known as the "instability catch". SUMMARY OF BACKGROUND DATA: The literature of fusion surgery for back pain relief in "mechanical" back pain reveals inconsistent results and in the majority presents only a vague description of these syndromes. Internal Lumbar Disc Degeneration with Instability catch "ILDDIC" may be one subset of these patients who are uniquely benefitted from spine stabilization. METHODS: The senior author (DAB) in midsummer 2015 began to offer smaller fusion procedures to selected patients on an overnight-stay basis using a standard perioperative care protocol. For practice audit, in December 2020 a mailed survey questionnaire requesting VAS pain scores and SF-36 physical function scores was sent out to all 111 patients who had been treated this way, which group included 30 cases of ILDDIC. We report here on the success of open PLIF reconstruction in achieving back pain relief for these patients. RESULTS: Some 24 of 30 patients returned the mailed survey questionnaire, and the remaining six could not be reached. All 24 responders reported significant relief of back pain and improved physical function, at a mean of 30 months from surgery. Review of the available clinical records (LFU < 1 year) from the six nonresponders also recorded positive early benefit. CONCLUSION: The diagnosis of ILDDIC requires both imaging and clinical correlates and may define a subgroup of the mechanical back pain population uniquely suited to achieve pain relief through lumbar fusion.

Normal Anatomy of the Lumbar Sublaminar Ridge in the Lateral Recess with Potential Implications to Surgical Technique in Degenerative Spinal Stenosis: A Cadaveric Study.

STUDY DESIGN: This is an anatomic study using cadaveric material. OBJECTIVE: To provide anatomic descriptions of the normal lumbar sublaminar ridge in the lateral recess and its potential to impact on the exiting nerve root there, with implications to surgical technique in lumbar spinal stenosis. SUMMARY OF BACKGROUND DATA: The lateral extent of the sublaminar ridge-the bony, superior insertion site of the ligamenta flava-and its topological relationship to the nerve root are not described in the literature. In the setting of degenerative lumbar stenosis this structure can hypertrophy and impinge the nerve root within the lateral recess even after excision of the corresponding ligamentum flavum. Failure to address this may contribute to failed lateral recess decompression. METHODS: Fifteen lumbar vertebrae, not obviously degenerated, were resected en bloc from three fixed adult human cadavers and then transected through the pedicles, leaving the posterior column and neural elements intact and articulated. The shape of the sublaminar ridge in the lateral recess and its relationship to the exiting nerve root were carefully examined. RESULTS: The exiting nerve root consistently crosses the sublami- nar ridge immediately inferior to the mid-pedicle, lateral to the subarticular gutter, and on the medial aspect of the true intervertebral foramen. A hypertrophic ridge can compress the exiting root by elevating the nerve root superiorly against the bony underside of the pedicle or displacing it anteriorly against the disc or vertebral body. CONCLUSION: The sublaminar ridge in the lateral recess may contribute to degenerative lumbar stenosis. Comprehensive appreciation of this anatomy may facilitate thorough lateral recess decompression.Level of Evidence: 4.

C2 Vertebral Corpectomy for Kyphosis Malunion of Remote Dens Fracture with Atlantoaxial Ankylosis and Myelopathy: A Case Report at 15 Years of Follow-Up.

CASE: We report a unique case of compressive myelopathy caused by late kyphosis angulation of a previously operated dens base fracture nonunion challenged by age-related ankyloses of the lateral articulations C1 to C2 and a solid posterior fusion mass. CONCLUSIONS: Posterior column shortening such as commonly practiced for progressive kyphosis or myelopathy may be precluded at the atlantoaxial level for potential vascular risk to the vertebral artery. A standard anterior cervical approach and the application of basic surgical spine care principles lead to a simple solution in the unique and highly complex anatomy of our case.

Radiographic outcomes of transosseous intradiscal screw fixation in lumbar reconstruction-Imaging results of an experience with an alternative in fixation of the unexpectedly osteopenic spine.

OBJECTIVE: To present the results of a new alternative in the technique lumbar pedicle screw reconstruction in osteopenic bone. Pedicle screw fixation is compromised in osteopenic bone and adjunct fixation commonly requires incremental technology that can increase cost and risk, and which may not commonly be available. Readily available low cost techniques are desirable. PATIENTS AND METHODS: This is a retrospective review of a prospectively accumulated case series of all patients presenting to the senior author's (DAB) practice for elective lumbar reconstruction at a tertiary spine referral center. All consecutive patients treated by the senior author 2002-2012 who were unexpectedly found to be severely osteopenic at surgery are reported. RESULTS: In seventy-four cases with imaging and clinical information available at an average of five years after surgery there was no screw lucency or accelerated disc degeneration observed despite these screws purposefully projecting into the suprajacent disc space within the limits of the construct. No patient had presented for instrumentation-related revision surgery of any sort. CONCLUSION: Transosseous intradiscal screw fixation is a potentially viable alternative in surgical stabilization of the unexpectedly osteopenic lumbar spine.

Description and Results of a Comprehensive Care Protocol for Overnight-Stay Spine Surgery in Adults.

STUDY DESIGN: This is a prospective cohort study. OBJECTIVE: The aim of this study was to define the probability of successful morning-after discharge after adult spine surgery achieved with a standard care protocol as applied to patients with a large variety of common degenerative spine disorders. SUMMARY OF BACKGROUND DATA: Qualifying criteria for ambulatory or overnight-stay adult spine surgery are not well defined in either the spine or anesthesia literature. Most reports simply go to American Society of Anesthesiology risk classification or surgical technique alternatives and do not present a clearly defined patient care and case management protocol. METHODS: A standardized protocol of patient preparation, preoperative comorbidities optimization, and perioperative care was applied in a prospective cohort of 126 patients including 83 lumbar and 41 cervical procedures. Office and hospital chart records were reviewed for relevant outcomes. RESULTS: Fully 122 of 124 appropriately selected cases were able to successfully achieve uneventful same-day discharge without any need for readmission, unscheduled early emergency room or clinic visits, or other major complications. Both failures were for urinary retention in senior males and resolved after a single-day admission to the main hospital. CONCLUSION: A wide variety of common degenerative spinal pathology in adults can be routinely and safely managed on an overnight-stay basis without requirement for formal hospital inpatient admission in patients appropriately selected and pre-educated to the experience and whose major comorbidities are preoperatively optimized. LEVEL OF EVIDENCE: N/A.

Solitary C1 Posterior Fixation for Unstable Isolated Atlas Fractures: Case Report and Systematic Review of the Literature.

Study Design A systematic review of the literature. Objectives To review the published results to date of motion-preserving direct reconstruction of C1 ring fractures with combined coronal plane displacement of at least 7 mm (rule of Spence) and so at risk for Dickman type I or II disruption of the transverse atlantal ligament (TAL). Methods A structured literature review prompted by successful management of a typical case. Results To date only 65 such cases are reported and follow-up is almost uniformly short. Although reported clinical success is uniform, the case mix is heterogenous and confirmation/classification of ligamentous injury at baseline is often lacking. Conclusions Direct C1 stabilization shows promise as a "more selective" option in managing displaced atlas fractures with probable TAL disruption but cannot yet be recommended as a practice standard. Prospective clinical studies are indicated and should be structured so as to differentiate between Dickman type I and type II injuries of the TAL.

Sacral Stress Fracture Mimicking Lumbar Radiculopathy in a Mounted Police Officer: Case Report and Literature Review.

Study Design Case report and review of the literature. Objective To present a unique case of L5 radiculopathy caused by a sacral stress fracture without neurologic compression. Methods We present our case and its clinical evolution and review the available literature on similar pathologies. Results Relief of the unusual mechanical loading causing sacral stress fracture led to rapid resolution of radiculopathy. Conclusion L5 radiculopathy can be caused by a sacral stress fracture and can be relieved by simple mechanical treatment of the fracture.

Dexamethasone Perioperative Coanalgesia in Lumbar Spine Fusion: A Controlled Cohort Study of Efficacy and Safety.

PURPOSE: A 48-hour trial of dexamethasone coanalgesia became our standard practice in May 2008. This is our research Ethics Board-approved review of this experience to date with attention to perioperative narcotics use and pain scores for the first 48 hours after surgery as well as length of stay (LOS), wound healing complications, and infections in the first 6 months, compared with the historical precedent control cohort. METHODS: Surgical case logs identified cases of 1- and 2-level elective lumbar decompression and fusion surgery performed since protocol initiation (cases) and for a like period beforehand (controls). Minimum of 6 months follow-up (sufficient to identify acute and subacute wound healing problems and perioperative infections) information was required. Hospital, Pain Service, and office records were reviewed for the extraction of outcomes data. RESULTS: We identified 132 cases and 146 controls. In 41 additional cases records were deficient. Baseline characteristics were equivalent. Cases included 70 males (53%) and 62 females (47%) of mean age 54 years (range, 18-84 y). Seventy-five (57%) cases were narcotics dependant (mean of 79.5 mg-morphine-equivalent daily). Controls included 78 males (53%) and 68 females (47%) of mean age 55 years (range, 27-85 y). Eighty-nine (61%) controls were narcotics dependant (mean 101.2 mg-morphine-equivalents daily). Mean morphine-equivalents narcotic consumption for 48 hours after surgery was 262.9 mg in cases and 280.7 mg in controls. VAS pain scores at 48 hours after surgery averaged 4.4 and 6.9 during rest and activity in the cases, and 3.7 and 6.3 during rest and activity in the controls. LOS averaged 3.9 days in cases and 5.2 days in controls. Delayed wound healing and surgical site infections were not observed in either group. CONCLUSIONS: Systemic dexamethasone after 1- and 2-level lumbar fusion surgery demonstrated minimal impact on 48 hours perioperative narcotics use with no detriment to pain control, wound healing, or infections. LOS was shortened by 25%.

Teriparatide treatment of a glucocorticoid-associated resorbing nonunion of a type III odontoid process fracture: a case report.

STUDY DESIGN: This is a unique case report. OBJECTIVES: To describe a successful case of Teriparatide treatment of odontoid nonunion. SUMMARY OF BACKGROUND DATA: Animal models suggest that this drug may enhance fracture healing, and there are 3 similar cases previously published elsewhere. METHODS: We describe the evolution of our case over time with serial computed tomography scan imaging confirming the treatment success. RESULTS: Drug treatment of the odontoid nonunion was successful. CONCLUSION: Drug treatment of the odontoid nonunion may be an option and merits formal study.

Uncovertebral anatomic midline targeting for cervical disc arthroplasty.

Study Design Prospective observational cohort. Objective To document the accuracy of uncovertebral anatomic targeting in positioning cervical disc arthroplasty. Summary of Background Data Disc arthroplasty implants depend on midline placement for optimum mechanical function. Fluoroscopy is used to delineate the midline. Anatomic targeting from the uncovertebral joints in the neck may be adequate. We have investigated the efficacy of uncovertebral anatomic targeting for cervical disc arthroplasty. Methods Anatomic uncovertebral midline targeting for disc arthroplasty insertion was performed in 18 male (mean age 51 years, range 27 to 67) and 22 female (mean age 50, range 35 to 70) patients receiving a total of 59 implants over a 5-year period. Device insertion was under only lateral imaging control. Postinsertion operative fluoroscopy with optimized centering was used to record implant position in the anteroposterior plane, and centerline analysis was performed using cursor measurement technology from the GE PACS™ imaging system (GE Medical Systems, Mt. Prospect, IL). Results Analysis found a mean deviation from the ideal midline placement of only 0.7 mm (range, 0 to 2.9 mm). Only three devices were more than 2 mm off the anatomic midline. Conclusion This anatomic technique is effective, safely minimizing imaging resource needs and X-ray exposure to the patient and operating team.

Spinal epidural hematoma.

Spinal epidural hematoma is a rare condition that usually presents with acute, severe pain at the location of the hemorrhage, with radiation to the extremities. It can rapidly develop to include progressive and severe neurologic deficit. The pathophysiology often remains unclear. However, epidural hematoma in the lumbar spine is best described as the result of internal rupture of the Batson vertebral venous plexus. Clinical evaluation of pain control and neurologic deficit is the most important tool in early diagnosis. Currently, MRI is the diagnostic method of choice. Regardless of the setting, symptomatic spinal epidural hematoma is typically managed with urgent surgical decompression of the spinal canal.

Tranexamic acid for hemostasis in the surgical treatment of metastatic tumors of the spine.

STUDY DESIGN: This is a retrospective study of sequential cohorts. OBJECTIVE: To assess the efficacy of tranexamic acid in decreasing operative blood loss and the need for intraoperative transfusion in metastatic spine surgery. SUMMARY OF BACKGROUND DATA: Significant published data have established the efficacy of antifibrinolytic drugs in limiting surgical bleeding during heart surgery and total joint replacement. One study in scoliosis suggested benefit in spine surgery as well. METHODS: During a 6-month trial period, 14 patients with spine cancer undergoing palliative intralesional tumor excision and concomitant instrumentation to stabilize the spine in the hands of a single surgeon were administered tranexamic acid intraoperatively in the attempt to minimize operative blood loss. They were then compared to the immediately preceding 14 patients. RESULTS: Estimated operative blood loss was 1385 mL in the study group treated with tranexamic acid and 1815 mL in controls not receiving the drug, and was not found to be significantly decreased in this study. CONCLUSIONS: Control of operative bleeding in metastatic spine surgery can be problematical. Optimum protocol might include routine preoperative angiographic tumor embolization to decrease lesion vascularity in all cases, but angiography is not without risk. Noninvasive prophylaxis of tumor bleeding would have obvious desirable advantages but was, unfortunately, not achieved in this study.

Failure of reconstitution of open-section, posterior iliac-wing bone graft donor sites after lumbar spinal fusion. Observations with implications for the etiology of donor site pain.

The objective of this cohort study--conducted at a regional trauma unit in southern Ontario, Canada--was to review the imaging history of open-section, iliac-wing bone graft donor sites in lumbar fusion patients. Intervention entailed review of available X-ray and CT scan images for all patients undergoing lumbar fusion with iliac autograft in the senior author's practice over a 4-year period. Outcome was radiographic confirmation of the absence of bony reconstitution at the iliac harvest site. Of 239 primary fusions performed, 209 complete imaging records were available for review. The images of a further 20 patients who had surgery with the senior author prior to the study period and who presented at the office in the first half of 2000 were also assessed. All cases showed persistence of the iliac donor harvest site defect. Only minimal marginal sclerosis to suggest attempted remodeling was observed. We conclude that iliac-wing bone graft donor sites do not remodel. Given that iliac harvesting is known to increase strain in the pelvis, and that lumbosacral stabilization increases stress in the pelvis, permanent deficiency of iliac bone stock at donor harvest site may be a factor in both primary donor site pain and the observed high frequency of this problem in lumbosacral fusion patients.

Assessment of stability of the cervical spine in blunt trauma patients: review of the literature, with presentation and preliminary results of a modified traction test protocol.

OBJECTIVE: To review the reported efficacy of various imaging techniques in assessing stability of the neck in blunt trauma patients, and to present the protocol and preliminary results of a modified traction test protocol. DESIGN: This is a prospective cohort study. SETTING: A regional trauma unit in Southern Ontario. PATIENTS: People with blunt-trauma injuries who came to the author's consultant practice with "C-spine not cleared" status, from January 2001 through December 2003. INTERVENTIONS: A fluoroscopically controlled test of axial traction followed by flexion/extension stressing. OUTCOME MEASURES: Radiographic confirmation of the absence of pathological motion under load. RESULTS: In 51 cases studied to date, no instabilities have been found. Four cases of minor ligamentous hypermobility have been detected, with stability confirmed and no surgery required. There have been no failures to depict the neck completely, no missed instabilities and no complications of the procedure. CONCLUSIONS: Cervical stability can be reliably confirmed with this test without any requirement for advanced imaging technology.

Efficacy of orthotic immobilization of the unstable subaxial cervical spine of the elderly patient: investigation in a cadaver model.

OBJECTIVE: To assess the efficacy of soft, semirigid and hard cervical collars to immobilize the neck in a destabilized cadaver model. DESIGN: This is a laboratory experiment. SETTING: The anatomy research lab of McMaster University. PATIENTS: None. Fresh cadavers from elderly patients suffering terminal medical illness and free of cervical structural disease were studied. INTERVENTIONS: Destabilizing discoligamentous lesions of the neck were created in the cadavers. Radiographs were taken in maximum displacement in the prone, decubitus and side-bending positions, first unsupported and then with soft, semirigid and hard collars applied. Displacements in angulation and translation were measured from the radiographs. OUTCOME MEASURES: Radiographic displacement under gravity load. RESULTS: In all cases there was no effective limitation of pathological displacement, and in many cases displacement was increased after collar application. CONCLUSIONS: Cervical collars do not effectively support the unstable neck, and may be ineffective in preventing pathological displacements.

Tensile failure of C2 pedicles and of subsequent direct repair in a porcine model.

STUDY DESIGN: This repeated-measures biomechanical study evaluated the tensile force required to cause bipedicular (hangman's) fractures in isolated porcine C2 specimens, and the subsequent force to failure after direct fracture repair with bipedicular lag screws. OBJECTIVES: To assess the pullout strength of direct lag screw fixation of hangman's fracture, relative to the strength of the intact specimens. SUMMARY OF BACKGROUND DATA: Clinical studies have reported successful treatment of hangman's fractures by direct screw repair followed by a collar after surgery. However, to the authors' best knowledge, there has not yet been a biomechanical analysis of the force required for screw pullout after direct repair. METHODS: Of 60 mounted porcine C2 specimens subjected to tensile anteroposterior force, hangman's fracture occurred in 15 cases, 12 of which were fixed with bipedicular 4.0-mm lag screws. These fixed specimens were retested to failure in the same manner. RESULTS: Most specimens had laminar fractures after the application of tensile force, with 15 of 60 (25%) showing bipedicular fractures. The force to bipedicular failure was 3259.1 +/- 148.5 N (mean +/- standard error of the mean). After screw fixation, the force to failure of the same specimens was 882.0 +/- 108.5 N (mean +/- standard error of the mean), or 27.3% of the intact bone. CONCLUSIONS: The pullout strength was substantial (882 N), although the relative strength of fixation was only 27.3% of the fracture strength shown by the intact specimens. The findings are discussed in relation to previous studies. To the authors' best knowledge, this is the first study to examine screw pullout forces after direct repair of hangman's fracture.