✓ Intramedullary spinal tuberculosis infection remains an extremely rare disease entity. In the most recent reviews only 148 cases have been reported in the world literature, although numerous recent reports from developing countries and on human immunodeficiency virus (HIV)—positive patients have increased this number. The authors present an unusual case of intramedullary tuberculoma in an HIV—negative patient from the southern United States who demonstrated no other signs or symptoms of tuberculosis infection. The authors believe that this is the first case of its kind to be presented in recent literature. The presentation of miliary disease via an isolated intramedullary spinal mass in a patient with no evident risk factors for tuberculosis infection emphasizes the importance of including tuberculosis in the differential diagnosis of spinal cord masses.
Intramedullary tuberculoma of the spinal cord
Case report and review of the literature
John K. Ratliff and Edward S. Connolly
Cervical laminoplasty: a critical review
John K. Ratliff and Paul R. Cooper
Object. The technique of cervical laminoplasty was developed to decompress the spinal canal in patients with multilevel anterior compression caused by ossification of the posterior longitudinal ligament or cervical spondylosis. There is a paucity of data confirming its superiority to laminectomy with regard to neurological outcome, preserving spinal stability, preventing postlaminectomy kyphosis, and the development of the “postlaminectomy membrane.”
Methods. The authors conducted a metaanalysis of the English-language laminoplasty literature, assessing neurological outcome, change in range of motion (ROM), development of spinal deformity, and complications. Seventy-one series were reviewed, comprising more than 2000 patients.
All studies were retrospective, uncontrolled, nonrandomized case series. Forty-one series provided postoperative recovery rate data in which the Japanese Orthopaedic Association Scale was used for assessing myelopathy. The mean recovery rate was 55% (range 20–80%). The authors of 23 papers provided data on the percentage of patients improving (mean ∼80%). There was no difference in neurological outcome based on the different laminoplasty techniques or when laminoplasty was compared with laminectomy. There was postlaminoplasty worsening of cervical alignment in approximately 35% and with development of postoperative kyphosis in approximately 10% of patients who underwent long-term follow-up review. Cervical ROM decreased substantially after laminoplasty (mean decrease 50%, range 17–80%). The authors of studies with long-term follow up found that there was progressive loss of cervical ROM, and final ROM similar to that seen in patients who had undergone laminectomy and fusion. In their review of the laminectomy literature the authors could not confirm the occurrence of postlaminectomy membrane causing clinically significant deterioration of neurological function. Postoperative complications differed substantially among series. In only seven articles did the writers quantify the rates of postoperative axial neck pain, noting an incidence between 6 and 60%. In approximately 8% of patients, C-5 nerve root dysfunction developed based on the 12 articles in which this complication was reported.
Conclusions. The literature has yet to support the purported benefits of laminoplasty. Neurological outcome and change in spinal alignment are similar after laminectomy and laminoplasty. Patients treated with laminoplasty develop progressive limitation of cervical ROM similar to that seen after laminectomy and fusion.
Multiple pituitary adenomas in Cushing's disease
John K. Ratliff and Edward H. Oldfield
Object. Clinically evident multiple pituitary adenomas rarely occur. The authors assess the incidence and clinical relevance of multiple adenomas in Cushing's disease.
Methods. A prospective clinical database of 660 pituitary surgeries was analyzed to assess the incidence of multiple pituitary adenomas in Cushing's disease. Relevant radiographic scans, medical records, and histopathological reports were reviewed.
Thirteen patients with at least two separate histopathologically confirmed pituitary adenomas were identified. Prolactinomas (nine patients) were the most common incidental tumors. Other incidental tumors included secretors of growth hormone ([GH], one patient) and GH and prolactin (two patients), and a null-cell tumor (one patient). In two patients, early repeated surgery was performed because the initial operation failed to correct hypercortisolism, in one instance because the tumor excised at the initial surgery was a prolactinoma, not an adrenocorticotropic hormone—secreting tumor. One patient had three distinct tumors.
Conclusions. Multiple pituitary adenomas are rare, but may complicate management of patients with pituitary disease.
Convection-enhanced delivery in intact and lesioned peripheral nerve
John K. Ratliff and Edward H. Oldfield
Object. Although the use of multiple agents is efficacious in animal models of peripheral nerve injury, translation to clinical applications remains wanting. Previous agents used in trials in humans either engendered severe side effects or were ineffective. Because the blood—central nervous system barrier exists in nerves as it does in the brain, limited drug delivery poses a problem for translation of basic science advances into clinical applications. Convection-enhanced delivery (CED) is a promising adjunct to current therapies for peripheral nerve injury. In the present study the authors assessed the capacity of convection to ferry macromolecules across sites of nerve injury in rat and primate models, examined the functional effects of convection on the intact nerve, and investigated the possibility of delivering a macromolecule to the spinal cord via retrograde convection from a peripherally introduced catheter.
Methods. The authors developed a rodent model of convective delivery to lesioned sciatic nerves (injury due to crush or laceration in 76 nerves) and compared the results to a smaller series of five primates with similar injuries. In the intact nerve, convective delivery of vehicle generated only a transient neurapraxic deficit. Early after injury (postinjury Days 1, 3, 7, and 10), infusion failed to cross the site of injury in crushed or lacerated nerves. Fourteen days after crush injury, CED of radioactively-labeled albumin resulted in perfusion through the site of injury to distal growing neurites. In primates, successful convection through the site of crush injury occurred by postinjury Day 28. In contrast, in laceration models there was complete occlusion of the extracellular space to convective distribution at the site of laceration and repair, and convective distribution in the extracellular space crossed the site of injury only after there was histological evidence of completion of nerve regeneration. Finally, in two primates, retrograde infusion into the spinal cord through a peripheral nerve was achieved.
Conclusions. Convection provides a safe and effective means to deliver macromolecules to regenerating neurites in crush-injured peripheral nerves. Convection block in lacerated and suture-repaired nerves indicates a significant intraneural obstruction of the extracellular space, a disruption that suggests an anatomical obstruction to extracellular and, possibly, intraaxonal flow, which may impair nerve regeneration. Through peripheral retrograde infusion, convection can be used for delivery to spinal cord gray matter. Convection-enhanced delivery provides a promising approach to distribute therapeutic agents to targeted sites for treatment of disorders of the nerve and spinal cord.
Cervical laminoplasty developments and trends, 2003–2013: a systematic review
Stephan Duetzmann, Tyler Cole, and John K. Ratliff
Despite extensive clinical experience with laminoplasty, the efficacy of the procedure and its advantages over laminectomy remain unclear. Specific clinical elements, such as incidence or progression of kyphosis, incidence of axial neck pain, postoperative cervical range of motion, and incidence of postoperative C-5 palsies, are of concern. The authors sought to comprehensively review the laminoplasty literature over the past 10 years while focusing on these clinical elements.
The authors conducted a literature search of articles in the Medline database published between 2003 and 2013, in which the terms “laminoplasty,” “laminectomy,” and “posterior cervical spine procedures” were used as key words. Included was every single case series in which patient outcomes after a laminoplasty procedure were reported. Excluded were studies that did not report on at least one of the above-mentioned items.
A total of 103 studies, the results of which contained at least 1 of the prespecified outcome variables, were identified. These studies reported 130 patient groups comprising 8949 patients. There were 3 prospective randomized studies, 1 prospective nonrandomized alternating study, 15 prospective nonrandomized data collections, and 84 retrospective reviews. The review revealed a trend for the use of miniplates or hydroxyapatite spacers on the open side in Hirabayashi-type laminoplasty or on the open side in a Kurokawa-type laminoplasty. Japanese Orthopaedic Association (JOA) scoring was reported most commonly; in the 4949 patients for whom a JOA score was reported, there was improvement from a mean (± SD) score of 9.91 (± 1.65) to a score of 13.68 (± 1.05) after a mean follow-up of 44.18 months (± 35.1 months). The mean preoperative and postoperative C2–7 angles (available for 2470 patients) remained stable from 14.17° (± 0.19°) to 13.98° (± 0.19°) of lordosis (average follow-up 39 months). The authors found significantly decreased kyphosis when muscle/posterior element–sparing techniques were used (p = 0.02). The use of hardware in the form of hydroxyapatite spacers or miniplates did not influence the progression of deformity (p = 0.889). An overall mean (calculated from 2390 patients) of 47.3% loss of range of motion was reported. For the studies that used a visual analog scale score (totaling 986 patients), the mean (cohort size–adjusted) postoperative pain level at a mean follow-up of 29 months was 2.78. For the studies that used percentages of patients who complained of postoperative axial neck pain (totaling 1249 patients), the mean patient number–adjusted percentage was 30% at a mean follow-up of 51 months. The authors found that 16% of the studies that were published in the last 10 years reported a C-5 palsy rate of more than 10% (534 patients), 41% of the studies reported a rate of 5%–10% (n = 1006), 23% of the studies reported a rate of 1%–5% (n = 857), and 12.5% reported a rate of 0% (n = 168).
Laminoplasty remains a valid option for decompression of the spinal cord. An understanding of the importance of the muscle-ligament complex, plus the introduction of hardware, has led to progress in this type of surgery. Reporting of outcome metrics remains variable, which makes comparisons among the techniques difficult.
Improved capture of adverse events after spinal surgery procedures with a longitudinal administrative database
Anand Veeravagu, Tyler S. Cole, Tej D. Azad, and John K. Ratliff
The significant medical and economic tolls of spinal disorders, increasing volume of spine surgeries, and focus on quality metrics have made it imperative to understand postoperative complications. This study demonstrates the utility of a longitudinal administrative database for capturing overall and procedure-specific complication rates after various spine surgery procedures.
The Thomson Reuters MarketScan Commercial Claims and Encounters and the Medicare Supplemental and Coordination of Benefits database was used to conduct a retrospective analysis of longitudinal administrative data from a sample of approximately 189,000 patients. Overall and procedure-specific complication rates at 5 time points ranging from immediately postoperatively (index) to 30 days postoperatively were computed.
The results indicated that the frequency of individual complication types increased at different rates. The overall complication rate including all spine surgeries was 13.6% at the index time point and increased to 22.8% at 30 days postoperatively. The frequencies of wound dehiscence, infection, and other wound complications exhibited large increases between 10 and 20 days postoperatively, while complication rates for new chronic pain, delirium, and dysrhythmia increased more gradually over the 30-day period studied. When specific surgical procedures were considered, 30-day complication rates ranged from 8.6% in single-level anterior cervical fusions to 27.3% in multilevel combined anterior and posterior lumbar spine fusions.
This study demonstrates the usefulness of a longitudinal administrative database in assessing postoperative complication rates after spine surgery. Use of this database gave results that were comparable to those in prospective studies and superior to those obtained with nonlongitudinal administrative databases. Longitudinal administrative data may improve the understanding of overall and procedure-specific complication rates after spine surgery.
Accurate identification of complications in spine surgery: an opportunity for excellence
Michael G. Fehlings and Sean R. Smith
Adult scoliosis surgery outcomes: a systematic review
Sanjay Yadla, Mitchell G. Maltenfort, John K. Ratliff, and James S. Harrop
Appreciation of the optimal management of skeletally mature patients with spinal deformities requires understanding of the natural history of the disease relative to expected outcomes of surgical intervention. Appropriate outcome measures are necessary to define the surgical treatment. Unfortunately, the literature lacks prospective randomized data. The majority of published series report outcomes of a particular surgical approach, procedure, or surgeon. The purpose of the current study was to systematically review the present spine deformity literature and assess the available data on clinical and radiographic outcome measurements.
A systematic review of MEDLINE and PubMed databases was performed to identify articles published from 1950 to the present using the following key words: “adult scoliosis surgery,” “adult spine deformity surgery,” “outcomes,” and “complications.” Exclusion criteria included follow-up shorter than 2 years and mean patient age younger than 18 years. Data on major curve (coronal scoliosis or lumbar lordosis Cobb angle as reported), major curve correction, Oswestry Disability Index (ODI) scores, Scoliosis Research Society (SRS) instrument scores, complications, and pseudarthroses were recorded.
Forty-nine articles were obtained and included in this review; 3299 patient data points were analyzed. The mean age was 47.7 years, and the mean follow-up period was 3.6 years. The average major curve correction was 26.6° (for 2188 patients); for 2129 patients, it was possible to calculate average curve reduction as a percentage (40.7%). The mean total ODI was 41.2 (for 1289 patients), and the mean postoperative reduction in ODI was 15.7 (for 911 patients). The mean SRS-30 equivalent score was 97.1 (for 1700 patients) with a mean postoperative decrease of 23.1 (for 999 patients). There were 897 reported complications for 2175 patients (41.2%) and 319 pseudarthroses for 2469 patients (12.9%).
Surgery for adult scoliosis is associated with improvement in radiographic and clinical outcomes at a minimum 2-year follow-up. Perioperative morbidity includes an approximately 13% risk of pseudarthrosis and a greater than 40% incidence of perioperative adverse events. Incidence of perioperative complications is substantial and must be considered when deciding optimal disease management. Although the quality of published studies in this area has improved, particularly in the last few years, the current review highlights the lack of routine use of standardized outcomes measures and assessment in the adult scoliosis literature.
Cranial neurosurgical 30-day readmissions by clinical indication
Nuriel Moghavem, Doug Morrison, John K. Ratliff, and Tina Hernandez-Boussard
Postsurgical readmissions are common and vary by procedure. They are significant drivers of increased expenditures in the health care system. Reducing readmissions is a national priority that has summoned significant effort and resources. Before the impact of quality improvement efforts can be measured, baseline procedure-related 30-day all-cause readmission rates are needed. The objects of this study were to determine population-level, 30-day, all-cause readmission rates for cranial neurosurgery and identify factors associated with readmission.
The authors identified patient discharge records for cranial neurosurgery and their 30-day all-cause readmissions using the Agency for Healthcare Research and Quality (AHRQ) State Inpatient Databases for California, Florida, and New York. Patients were categorized into 4 groups representing procedure indication based on ICD-9-CM diagnosis codes. Logistic regression models were developed to identify patient characteristics associated with readmissions. The main outcome measure was unplanned inpatient admission within 30 days of discharge.
A total of 43,356 patients underwent cranial neurosurgery for neoplasm (44.23%), seizure (2.80%), vascular conditions (26.04%), and trauma (26.93%). Inpatient mortality was highest for vascular admissions (19.30%) and lowest for neoplasm admissions (1.87%; p < 0.001). Thirty-day readmissions were 17.27% for the neoplasm group, 13.89% for the seizure group, 23.89% for the vascular group, and 19.82% for the trauma group (p < 0.001). Significant predictors of 30-day readmission for neoplasm were Medicaid payer (OR 1.33, 95% CI 1.15–1.54) and fluid/electrolyte disorder (OR 1.44, 95% CI 1.29–1.62); for seizure, male sex (OR 1.74, 95% CI 1.17–2.60) and index admission through the emergency department (OR 2.22, 95% CI 1.45–3.43); for vascular, Medicare payer (OR 1.21, 95% CI 1.05–1.39) and renal failure (OR 1.52, 95% CI 1.29–1.80); and for trauma, congestive heart failure (OR 1.44, 95% CI 1.16–1.80) and coagulopathy (OR 1.51, 95% CI 1.25–1.84). Many readmissions had primary diagnoses identified by the AHRQ as potentially preventable.
The frequency of 30-day readmission rates for patients undergoing cranial neurosurgery varied by diagnosis between 14% and 24%. Important patient characteristics and comorbidities that were associated with an increased readmission risk were identified. Some hospital-level characteristics appeared to be associated with a decreased readmission risk. These baseline readmission rates can be used to inform future efforts in quality improvement and readmission reduction.