Management and avoidance of lumbar pseudarthrosis are among the most common and challenging tasks faced by reconstructive spine surgeons. The risks of peudarthrosis can be broadly divided into two categories: those within a surgeon's control and those not within his/her control. These include biological factors, graft choices, site preparation, and surgical design. The authors review the biological factors that affect fusion and how they can be manipulated to avoid or manage lumbar pseudarthrosis. Surgical planning and construct design to prevent or treat pseudarthrosis will also be discussed. Additionally, the importance of restoring sagittal balance will be reviewed.
Stephen L. Ondra and Shaden Marzouk
Gregory C. Wiggins, Stephen L. Ondra and Christopher I. Shaffrey
Iatrogenic loss of lordosis is now frequently recognized as a complication following placement of thoracolumbar instrumentation, especially with distraction instrumentation. Flat-back syndrome is characterized by forward inclination of the trunk, inability to stand upright, and back pain. Evaluation of the deformity should include a full-length lateral radiograph obtained with the patient's knees and hips fully extended. The most common cause of the deformity includes the use of distraction instrumentation in the lumbar spine and pseudarthrosis.
Surgical treatment described in the literature includes opening (Smith-Petersen) osteotomy, polysegmental osteotomy, and closing wedge osteotomy. The authors will review the literature, cause, clinical presentation, prevention, and surgical management of flat-back syndrome.
Sean A. Salehi, Randall R. McCafferty, Dean Karahalios and Stephen L. Ondra
✓ The management of tumors that metastasize to the sacrum remains controversial. Typically, resection of such tumors and reconstruction of the lumbopelvic junction requires sacrifice of neural elements resulting in neurological dysfunction and prolonged periods of bed rest. This severely affects the quality of life in patients in whom there is frequently a limited life expectancy.
The authors describe three patients who underwent subtotal resection of metastatic sacral tumors. Postoperatively, good outcome was demonstrated in all patients.
The authors present a technique for debulking and reconstruction that provides immediate spinopelvic junction stability and allows for early mobilization. Quality of life is significantly improved compared with that resulting from either medical treatment or traditional surgery.
Stephen L. Ondra, Henry Troupp, Eugene D. George and Karen Schwab
✓ The authors have updated a series of 166 prospectively followed unoperated symptomatic patients with arteriovenous malformations (AVM's) of the brain. Follow-up data were obtained for 160 (96%) of the original population, with a mean follow-up period of 23.7 years. The rate of major rebleeding was 4.0% per year, and the mortality rate was 1.0% per year. At follow-up review, 23% of the series were dead from AVM hemorrhage. The combined rate of major morbidity and mortality was 2.7% per year. These annual rates remained essentially constant over the entire period of the study. There was no difference in the incidence of rebleeding or death regardless of presentation with or without evidence of hemorrhage. The mean interval between initial presentation and subsequent hemorrhage was 7.7 years.
Harel Deutsch, Praveen V. Mummaneni, Regis W. Haid, Gerald E. Rodts and Stephen L. Ondra
Primary tumors of the sacrum are rare. In adults, the most common sacral tumors are metastases. The most common primary sacral tumor is a chordoma. Chordomas along as well as tumors such as chondrosarcomas, osteosarcomas, myxopapillary ependymomas, myelomas, and Ewing sarcomas are considered malignant. In this article the authors focus on benign sacral tumors.
Michael K. Rosner, Timothy R. Kuklo, Rabih Tawk, Ross Moquin and Stephen L. Ondra
The purpose of this study was to evaluate the safety and efficacy of prophylactic inferior vena cava (IVC) filter placement in high-risk patients who undergo major spine reconstruction.
In the pilot study, 22 patients undergoing major spine reconstruction received prophylactic IVC filters. These patients were prospectively followed to evaluate complications related to the filter, the rate of deep venous thrombosis (DVT) formation, and the rate of pulmonary embolism (PE). These data were compared with those obtained in a retrospective review for PE in a matched cohort treated at the same institution. At a second institution the treatment guidelines were implemented in 17 patients undergoing complex spine surgery with the same follow-up criteria.
In the pilot study, no patient experienced PE (0%), whereas two had DVT (9%). Bilateral DVT developed postoperatively in one patient (associated morbidity rate 4.5%), who required thrombolytic therapy. One patient died of unrelated surgical complications. The PE rate in the matched cohort at the same institution was 12%. At the second institution, no patient had PE, and no complications were noted.
In this patient population, prophylactic IVC filter placement appears to decrease the PE rate substantially, from 12 to 0%. The placement of IVC filters appears to be a safe and efficacious intervention for prevention of PE in high-risk patients.
Michael K. Rosner, David W. Polly Jr., Timothy R. Kuklo and Stephen L. Ondra
Techniques to improve segmental fixation have advanced the ability to correct complex spinal deformity. The purpose of instrumentation is to correct spinal deformity or to stabilize the spine to enhance the long-term biological fusion. The ultimate goal of spinal deformity surgery is the creation of a stable, balanced, pain-free spine centered over the pelvis in the coronal and sagittal planes. The minimum number of segments should be fused. These concepts remain challenging in the setting of deformity and instability. Successful results can be obtained if the surgeon understands the technology available, its capabilities, biological limitations, and the desired solution.
The authors prefer to use thoracic pedicle screws when treating patients with spinal deformity because they provide greater corrective forces for realignment. This allows shorter-segment constructs and the possibility of true derotation in correction. In this article the authors focus on the use of thoracic transpedicular screw fixation in the management of complex spinal disorders and deformity.
Patrick C. Hsieh, Stephen L. Ondra, Robert J. Wienecke, Brian A. O'Shaughnessy and Tyler R. Koski
✓The authors describe the use of sacral pedicle subtraction osteotomy (PSO) with multiple sacral alar osteotomies for the correction of sacral kyphosis and pelvic incidence and for achieving sagittal balance correction in cases of fixed sagittal deformity after a sacral fracture.
In this paper, the authors report on a novel technique using a series of sacral osteotomies and a sacral PSO to correct a fixed sagittal deformity in a patient with a sacral fracture that had healed in a kyphotic position. The patient sustained this fracture after a previous surgery for multilevel instrumented fusion. Preoperative and postoperative radiographic studies are reviewed and the clinical course and outcome are presented.
Experts agree that the pelvic incidence is a fixed parameter that dictates the morphological characteristics of the pelvis and affects spinopelvic orientation and sagittal spinal alignment. An increased pelvic incidence is associated with a higher degree of spondylolisthesis in the lumbosacral junction, and increased shear forces across this junction. The authors demonstrate that the pelvic incidence can be altered and corrected with a series of sacral osteotomies to improve sacral kyphosis, compensatory lumbar hyperlordosis, and sagittal balance.
Russell R. Reid, José Dutra, David B. Conley, Stephen L. Ondra and Gregory A. Dumanian
✓ Esophageal injury is a serious complication of anterior cervical fusion. A team approach to the management of these cases is described. The authors performed spinal assessment, control of the fistula, and interposition of a vascularized flap between the spine and the esophagus. They compared the overall efficacy of the pectoralis major flap (pedicled; two cases) and omental flap (free; two cases).
Patrick C. Hsieh, Robert J. Wienecke, Brian A. O'Shaughnessy, Tyler R. Koski and Stephen L. Ondra
Pyogenic vertebral discitis and osteomyelitis (PVDO) has become an increasing problem for the spine surgeon. Despite recent advances in medical care and improved diagnostic neuroimaging, PVDO remains a major cause of illness and death in the elderly population. Infection of the spinal column often presents insidiously; however, if not treated appropriately and in a timely manner it can lead to severe neurological impairment, systemic septicemia, and progressive spinal deformity. In this paper the authors review the epidemiological and pathophysiological features and the clinical presentation of PVDO. Conventional medical therapy is described, with a particular focus on the methods of diagnosis. Surgical strategies for PVDO are then presented based on the literature and according to the practice of the senior author (S.L.O.), with an emphasis placed on structural considerations, implant selection, and techniques for augmenting vascular tissue to the site of infection.