Development and Validation of a Prediction Model for Pain and Functional Outcomes After Lumbar Spine Surgery.

Importance: Functional impairment and pain are common indications for the initiation of lumbar spine surgery, but information about expected improvement in these patient-reported outcome (PRO) domains is not readily available to most patients and clinicians considering this type of surgery. Objective: To assess population-level PRO response after lumbar spine surgery, and develop/validate a prediction tool for PRO improvement. Design, Setting, and Participants: This statewide multicenter cohort was based at 15 Washington state hospitals representing approximately 75% of the state's spine fusion procedures. The Spine Surgical Care and Outcomes Assessment Program and the survey center at the Comparative Effectiveness Translational Network prospectively collected clinical and PRO data from adult candidates for lumbar surgery, preoperatively and postoperatively, between 2012 and 2016. Prediction models were derived for PRO improvement 1 year after lumbar fusion surgeries on a random sample of 85% of the data and were validated in the remaining 15%. Surgical candidates from 2012 through 2015 were included; follow-up surveying continued until December 31, 2016, and data analysis was completed from July 2016 to April 2017. Main Outcomes and Measures: Functional improvement, defined as a reduction in Oswestry Disability Index score of 15 points or more; and back pain and leg pain improvement, defined a reduction in Numeric Rating Scale score of 2 points or more. Results: A total of 1965 adult lumbar surgical candidates (mean [SD] age, 61.3 [12.5] years; 944 [59.6%] female) completed baseline surveys before surgery and at least 1 postoperative follow-up survey within 3 years. Of these, 1583 (80.6%) underwent elective lumbar fusion procedures; 1223 (77.3%) had stenosis, and 1033 (65.3%) had spondylolisthesis. Twelve-month follow-up participation rates for each outcome were between 66% and 70%. Improvements were reported in function, back pain, and leg pain at 12 months by 306 of 528 surgical patients (58.0%), 616 of 899 patients (68.5%), and 355 of 464 patients (76.5%), respectively, whose baseline scores indicated moderate to severe symptoms. Among nonoperative patients, 35 (43.8%), 47 (53.4%), and 53 (63.9%) reported improvements in function, back pain, and leg pain, respectively. Demographic and clinical characteristics included in the final prediction models were age, sex, race, insurance status, American Society of Anesthesiologists score, smoking status, diagnoses, prior surgery, prescription opioid use, asthma, and baseline PRO scores. The models had good predictive performance in the validation cohort (concordance statistic, 0.66-0.79) and were incorporated into a patient-facing, web-based interactive tool (https://becertain.shinyapps.io/lumbar_fusion_calculator). Conclusions and Relevance: The PRO response prediction tool, informed by population-level data, explained most of the variability in pain reduction and functional improvement after surgery. Giving patients accurate information about their likelihood of outcomes may be a helpful component in surgery decision making.

Cellular Events and Pathophysiology of SCI.

Spinal cord injury (SCI) has occurred in 2.5 million people worldwide, and 130,000 new cases are reported each year. SCI most commonly consists of a compression injury with hemorrhage into gray matter and loss of neurons, oligodendroglia, and astrocytes, followed by invasion of lymphocytes and macrophages; cavitation of the cord follows, then Wallerian degeneration of ascending and descending tracts and loss of neuronal circuitry, culminating in glial scar perpendicular to the direction of the axon. Onset of necrosis occurs within 24 hours. Spontaneous repair is incomplete and involves limited sprouting of axons and new spinal circuits that bypass the lesion and move into descending tracts, resulting in indirect connections with lumbar motor neurons.

Inferior vena cava thrombosis causing acute cauda equina syndrome. Case report.

The authors report a case of a 16-year-old girl who presented with a 1-week history of progressive low-back pain, buttock paresthesias, and bilateral lower extremity pain and weakness. Magnetic resonance (MR) imaging and MR venography studies of her lumbar spine revealed engorgement of the epidural venous plexus and mild compression of the cauda equina. A lower extremity and pelvic venogram revealed occlusive thrombosis of the femoral and iliac veins as well as of the inferior vena cava (IVC). The patient required an IVC thrombectomy due to progressive symptoms, after which she improved and returned to baseline status in 1 week. Imaging studies afterwards showed resolution of the venous engorgement and decompression of the cauda equina. This is the second published report of an association between IVC thrombosis and cauda equina syndrome.

Charcot arthropathy in relation to autonomic dysreflexia in spinal cord injury: case report and review of the literature.

Charcot spinal arthropathy has been described as a late complication of spinal cord injury. In patients with these injuries in whom the spine below the level of injury is insensate, joint trauma can progress until spinal instability ensues. The authors describe the case of a 50-year-old man with complete C-8 tetraplegia who experienced a 4-month history of episodic severe headaches, profuse sweating over his face and arms, and episodic severe hypertension in addition to a "grinding" sensation in the lower back. Charcot arthropathy at the T11-12 levels with pathological mobility was demonstrated on neuroimaging. Intraoperatively, a complete spinal cord transection was identified. Anterior and posterior thoracolumbar fusion across the mobile segment resulted in complete amelioration of signs and symptoms of autonomic dysreflexia. This entity, a common condition in the setting of spinal cord injury, has many triggers. Definitive treatment is targeted at the removal of the underlying cause. As demonstrated here, Charcot spinal arthropathy can act as a powerful trigger for induction of autonomic dysreflexia. Treatment of the associated spinal instability resulted in eradication of all signs and symptoms of the dysreflexia.

Aneurysmal bone cyst of the atlas: successful treatment through selective arterial embolization: case report.

OBJECTIVE AND IMPORTANCE: Aneurysmal bone cysts (ABCs) are benign and expansile osteolytic lesions that can occur in any location in the spine, including the craniovertebral junction. Aggressive resection followed by bone grafting has been the mainstay of treatment, with selective arterial embolization as a presurgical adjunct. Complete excision of these lesions at the craniovertebral junction is associated with high surgical morbidity. We report a case of successful treatment of an ABC of the atlas in a child with selective arterial embolization alone. CLINICAL PRESENTATION: A 10-year-old girl presented with persistent neck pain after a snowboarding accident. Computed tomography and magnetic resonance imaging of the cervical spine revealed an expansile cystic mass involving the right lateral mass of C1. Digital subtraction angiography revealed a tumor blush, which, along with the cystic appearance of the lesion, was consistent with an ABC. INTERVENTION: The arterial feeders to the lesion were selectively embolized with polyvinyl alcohol particles. Three sessions of embolization were required to eradicate the blood supply to the lesion completely. CONCLUSION: Complete surgical resection of ABCs at the craniovertebral junction can be associated with high morbidity secondary to the highly vascular and destructive nature of these lesions. The case discussed here demonstrates the viability of selective arterial embolization as a primary and stand-alone modality of treatment.