Christopher J. Dewald

Instrumentation-related complications of multilevel fusions for adult spinal deformity patients over age 65 : Surgical considerations and treatment options in patients with poor bone quality

Study Design. Retrospective follow-up of patients over the age of 65 with a minimum of five-level fusions. Objective. To determine the effect on outcomes of long constructs in patients with poor bone stock, and to review surgical techniques used in patients with poor bone stock. Summary of Background Data. Scoliotic deformities in patients with poor bone stock require alterations in both the surgical technique and preoperative planning. To our knowledge, complications of long constructs in poor bone stock have not been specifically reported. Methods. Patients over the age of 65 that underwent a minimum of five-level fusion over a 5-year period were reviewed. We reviewed both operative reports and clinic notes and recorded both early and late complications. Results. Early complications included pedicle fractures and compression fractures with an overall rate of 13%. Late complications included pseudarthroses with instrumentation failure, adjacent level disc degeneration with herniation, compression fractures, and progressive kyphosis. Progressive junctional kyphosis occurred in 26% of patients. Conclusions. Spinal stabilization surgery in patients with poor bone stock is associated with high complication rates. Complications such as progressive kyphosis adjacent to the fusion are difficult to address with instrumentation alone.

Evaluation and management of high-grade spondylolisthesis in adults.

Study Design. A retrospective review was performed on 21 adult patients surgically treated with high-grade spondylolisthesis (Grade III, IV, or V). Additionally, the natural history, classification, and surgical alternatives for high-grade spondylolisthesis in the adult are discussed through literature review. Objectives. The purpose of this article is to review the clinical and radiographic outcomes of surgical treatment of high-grade spondylolisthesis in the adult from a single institution. The natural history and treatment options for these adults are described in this review. Summary of Background Data. High-grade spondylolisthesis is typically diagnosed and treated in the child or adolescent. Most patients with high-grade spondylolisthesis received surgical treatment during their adolescence. Some patients, however, remain minimally symptomatic for life without surgery. Little has been written on the natural history or treatment of adults with high grades of spondylolisthesis. Most of the published reports on the surgical treatment of high-grade spondylolisthesis pertain to skeletally immature patients and maybe include a few adults in their series. Nonetheless, the different techniques of surgical treatment for high-grade spondylolisthesis that have been described in these studies can help the spinal surgeon in treatment options for this rare but difficult spinal deformity. Methods. A literature review of the published manuscripts on the treatment of high-grade spondylolisthesis was performed with particular attention to the natural history and surgical treatment involving adult patients. Adult patients (older than 21 years) with high-grade spondylolisthesis treated surgically were retrospectively reviewed. Patients’ clinical charts and radiographs were reviewed before and after surgery. Determination of fusion success, clinical outcome, and complications were performed. Results. Twenty-one consecutive adults with high-grade spondylolisthesis who underwent lumbar spinal surgery were review retrospectively between 1990 and 2004. There were 13 females and 8 males with an average age of 35 years (range, 21–68 years). The average follow-up was 6.6 years. There were 11 Grade III, 6 Grade IV, and 4 Grade V slips, including 4 acquired and 17 devel opmental spondylolistheses. There were no pseudarthroses or significant instrumentation failures. There was 1 case of a complete cauda equina syndrome on a patient with preoperative symptoms of an incomplete cauda equina syndrome. Conclusions. Adult patients with high-grade spondylolisthesis not responding to nonoperative treatment can be stabilized in situ with posterior instrumentation from L4 to S1. The use of adjunctive fixation with iliac screws and/or transvertebral screws is recommended for the adult patient, particularly in revision or unstable cases. Reduction of the slipped vertebrae remains controversial for all grades of spondylolisthesis and more so for the adult patient. Partial reduction of the slip angle, decreasing the lumbosacral kyphosis, should be considered if significant sagittal malalignment is present or to improve arthrodesis success. Anterior column support should be performed, particularly when reduction has been obtained. Anterior column support can be performed, anteriorly or posteriorly, either by using inter vertebral body structural strut support or with a transsacral fibular dowel to improve stability and success of arthrodesis.

The Superior Mesenteric Artery Syndrome in Patients with Spinal Deformity

Study Design. A retrospective review. Objective. To determine the incidence of the superior mesenteric artery syndrome (SMAS) after surgical correction for scoliosis and if it is influenced by newer derotation/translation surgical systems. Summary of Background Data. The SMAS is a known complication after surgery. Method. Of 2939 charts reviewed, 17 patients between 1960 and 2002 matched inclusion criteria. Results. Our incidence of the SMAS was 0.5%. Onset of symptoms was 7.2 days. Several scoliosis diagnoses were included in the study group. Instrumentation that was used included: nondistraction systems (n = 14), Harrington rod with body cast (n = 1), Luque rod with sublaminar wires (n = 1), and casted in situ posterior spinal fusion (n = 1). Before surgery, 10 of 17 patients weighed less than the 50th percentile. Mean preoperative BMI was 18.6 kg/cm/cm. Postoperative height gain averaged 3.175 cm, and weight loss at onset of symptoms averaged 4.5 kg. There were 14 patients who required nasogastric suction for an average duration of 10.2 days, 11 required hyperalimentation, and 5 concurrently received hyperalimentation with enteric feeding. The SMAS recurred in 2 patients. Conclusions. Postoperative weight loss appears to be more important for the development of the SMAS than asthenic body type. Newer derotation/translation corrective techniques have not eliminated the SMAS. Gastrointestinal imaging is indicated when nausea and vomiting occur 6−12 days after surgery, associated with early satiety and normal bowel sounds. Decompression and nutritional support remain the mainstays of treatment.

Traumatic posterior spondyloptosis at the lumbosacral junction. A case report.

Fracture-dislocations at the lumbosacral junction are invariably the consequence of high-energy trauma and occur more commonly in the anterior direction. Dislocations in the posterior direction are considered rare and have been reported infrequently. On review of the literature, we discovered only eight reported cases of traumatic lumbosacral retrolisthesis 1-8. Furthermore, anterior fracture-dislocations of the lumbosacral spine tend to occur as a result of flexion-distraction and shear forces, whereas it is postulated that posterior dislocations occur as a result of shear and hyperextension forces. We present the case of a patient with a traumatic posterior L5-S1 fracture-dislocation that resulted in severe neurological compromise with partial avulsion of the cauda equina. The purpose of this report is to discuss the proposed mechanism of injury and to detail the recommended treatment of such injuries. The patient was informed that data concerning the case would be submitted for publication. A fifteen-year-old girl was struck by a motor vehicle from behind and dragged approximately 15 m. Notable findings on examination included deep skin abrasions along a large portion of the back. The patient presented with severe paraparesis of both lower extremities below the L3 level and diminished sensation to light touch and pinprick below the L4 level. She had diminished perirectal sensation and loss of anal sphincter tone. The Achilles reflex was absent bilaterally. A lateral plain radiograph demonstrated a complete fracture-dislocation of the L5 vertebral body posterior to the sacrum ( Fig. 1 ). This finding was confirmed by a sagittal magnetic resonance image ( Fig. 2 ) that revealed a fracture line through the anteroinferior corner of the L5 vertebral body. Computed tomography revealed bilateral fracture of the pars interarticularis, complete displacement of the remaining L5 vertebral body posterior to the sacrum, and a sagittal fracture of the posterior part …

Long Structural Allografts in the Treatment of Anterior Spinal Column Defects

A retrospective study of 41 patients who had anterior spinal column reconstruction using long-segment allografts between 1983 and 1998 is reported. A long-segment allograft was defined as an allograft strut that replaces a vertebral body or approximates the height of the adjacent vertebral body for the thoracolumbar or lumbar spine, or more than two vertebral bodies for the cervical or cervicothoracic spine. Forty of the 41 patients had successful anterior strut grafting with radiographic evidence of allograft incorporation at the last followup with the majority of patients having radiographic evidence of incorporation by 6 months. There where three early complications related to the allograft (two end plate fractures and one repeated cervical spine allograft dislodgment) and one late complication associated with the posterior adjunct instrumentation unrelated to the allograft (degenerative lumbar stenosis). The only procedural complication was a deep venous thrombosis and a resultant nonfatal pulmonary embolus. No allografts fractured or collapsed. These data suggest that long-segment anterior allografts work exceptionally well in maintaining vertebral height and structural integrity in numerous pathologic deformities including traumatic and infectious etiologies.

Free Vascularized Fibular Strut Autografts to the Lumbar Spine in Complex Revision Surgery: A Report of Two Cases.

This case report presents two patients who underwent fibular strut grafting for complex revisions of previous lumbar spine arthrodeses. A case review of the Electronic Medical Record at the index institution was performed to evaluate the timeline of events of the two patients who underwent fibular strut grafting for complex revisions of previous lumbar spine arthrodesis, including imaging studies, progress notes, and laboratory results. One patient had developed chronic L3 vertebral body osteomyelitis from a prior fibular allograft and instrumentation placed for a traumatic burst fracture. The second patient had a severe scoliosis recalcitrant to prior arthrodeses in the context of Marfan syndrome and a persistent L4-5 pseudarthrosis. Both patients underwent free vascularized fibular autograft revision arthrodeses. At most recent long-term follow-up, both patients had improved clinically and neither had required further revision. The use of free vascularized fibular grafting is an excellent option for a variety of spinal indications, and these two reports indicate that the technology may have an indication for use after multiple failed surgeries for osteomyelitis or correction of a multi-level large spinal deformity secondary to Marfan syndrome.

Late Fracture After Long Spinal Fusion for Idiopathic Scoliosis: A Case Report

STUDY DESIGN Case report. OBJECTIVES To report a case of late atraumatic fracture of a long spinal fusion for idiopathic scoliosis 37 years after removal of instrumentation and review the literature on this complication. SUMMARY OF BACKGROUND DATA Late fracture of a long spinal fusion performed for idiopathic scoliosis is rare, with only several cases reported in the literature. METHODS The authors report a case of atraumatic fracture of a long fusion mass in a 55-year-old woman who underwent spinal fusion with Harrington rods at age 14 years with Harrington rod removal at age 18 years. She subsequently developed flat-back syndrome at age 49 years and underwent L3-4, L4-5, and L5-S1 Smith-Peterson osteotomies and posterolateral segmental instrumentation fusion from T12 to pelvis. She developed acute-onset mid-thoracic pain after a minor twisting injury without radiation or neurologic deficit, and was found on magnetic resonance imaging to have a fracture through the fusion mass at T6-7 with increased activity at this location on bone scan. RESULTS The patient failed conservative treatment with a high custom-molded brace and underwent posterior segmental spinal instrumentation and fusion from T2 to the previous instrumentation at L2 with autograft and allograft. She had immediate improvement of back pain postoperatively and has recovered well from the surgery. CONCLUSIONS Late fracture through a long fusion mass is a rare long-term complication of spine fusion for idiopathic scoliosis. In this case report, we report successful treatment of a fracture with a long lever arm of a solid posterior fused spine with posterior instrumented fusion multiple levels above and below the fracture.

Traumatic sacral spondylolisthesis

Abstract Purpose of study: Increased fracture rates among osteoporotic patients in proximity to instrumentation and prosthetic joint replacements is well documented in the literature. The authors have recently described burst fractures of the caudal end-instrumented lumbar vertebrae in adult patients treated with an instrumented fusion for scoliosis. The purpose of this study was to describe traumatic sacral spondylolisthesis (TSS), which is a newly recognized complication resulting from the surgical management of adult deformity after instrumentation to the sacrum, and to suggest possible treatment options. Methods used: Review of four patients with symptomatic spinal deformities and osteoporosis who were treated with surgical intervention. Each patient subsequently developed an insufficiency fracture and olisthesis of S1. of findings: Four patients averaging 60 years of age (range, 36 to 78 years) underwent a combined anterior and posterior spinal fusion to the sacrum averaging 9 levels (range, 3 to 13). Preoperative diagnoses included degenerative spondylolisthesis (n=2), degenerative scoliosis (n=1) and Charcot spine (n=1). Insufficiency fractures of the sacrum resulting in a traumatic S1 spondylolisthesis was documented an average of 7 weeks postoperatively in these patients (range, 5 to 12). Minor trauma resulting from a fall was documented in two patients. Two patients did not have a clear history of significant trauma associated with the onset of symptoms. Anterior olisthesis of the proximal S1 fragment varied from 20% to 100%. Three patients did not progress, and one patient with a 40% olisthesis progressed to a spondyloptosis. Intermittent urinary incontinence with urgency as a result of high-grade stenosis was identified in a patient with traumatic spondyloptosis. All patients had significant pain. One patient presented with the hallmark clinical posture of a high-grade spondylolisthesis. The two patients with spondyloptosis elected surgical intervention. One of these patients developed incontinence and underwent decompression, partial reduction and extension of the fusion to the ilium. Another patient underwent extension of the fusion to the ilium without reduction. The remaining two patients were treated nonoperatively. All patients demonstrated clinical improvement at most recent follow-up. Relationship between findings and existing knowledge: Combined anterior and posterior fusion may create stress risers at adjacent levels. In the osteoporotic patient this may result in insufficiency fractures. Sacral insufficiency fractures as a consequence of spinal instrumentation have not been previously described. These fractures may present with painful instability and symptoms of neurologic compression similar to that seen in high-grade developmental spondyloptosis. Overall significance of findings: In the osteoporotic patient preoperative consideration should be given to constructs that are shorter and that preserve a distal buffer zone between the lowest instrumented vertebrae and the sacrum. In addition, decreasing the stiffness of the constructs may help to decrease the magnitude of stress transferred to the adjacent vertebral levels or the sacrum. Developing a plan of treatment for a patient with TSS of S1 must take into consideration the degree of displacement, neurologic symptoms and the general health and goals of the patient. Nonsurgical treatment is appropriate for patients who cannot tolerate a significant spinal reconstruction to the ilium or the potential significant blood loss that could result from disimpaction and realignment of the fracture. Nonoperative care consisting of an extended period of bedrest has resulted in acceptable outcome. However, the risks of prolonged bed rest in the elderly is not benign. Surgical intervention to perform reduction and stabilization is an attractive, definitive option for patients who are physiologically robust. The benefit of surgical repair is the ability to decompress the neural elements and achieve rapid mobilization. Disclosures: No disclosures. Conflict of interest: No conflicts.