D Samartzis

Is autograft the gold standard in achieving radiographic fusion in one-level anterior cervical discectomy and fusion with rigid anterior plate fixation?

Study Design. A review of 66 consecutive patients at a single institution who underwent one-level anterior cervical discectomy and fusion (ACDF) with rigid anterior plate fixation with allograft or autograft. Objectives. To address the efficacy of allograft to autograft with primary respect to fusion rate and secondary attention to risk factors and clinical outcome in patients undergoing one-level ACDF with rigid anterior plate fixation. Summary of Background Data. Although autograft is considered the gold standard in achieving optimal fusion, when compared with allograft in noninstrumented one-level ACDF and in plated and nonplated multilevel ACDF, the efficacy of allograft to autograft in one-level ACDF with rigid anterior plate fixation is not thoroughly understood. Methods. Sixty-six consecutive patients (mean age, 45 years) at a single institution who underwent one-level ACDF with rigid anterior plate fixation with allograft (n = 35) or autograft (n = 31) were reviewed for radiographic fusion (mean, 12 months), risk factors, and clinical outcome (mean, 17 months). Smokers entailed 33.3% of the patients, and 45.5% of all patients presented with a work-related injury. An independent blinded observer reviewed at last follow-up lateral neutral and flexion/extension plain radiographs for radiographic fusion and instrumentation integrity. Clinical outcome was assessed on last follow-up and rated according to the Odom criteria. The threshold for statistical significance was established at P < 0.05. Results. Solid fusion was achieved in 63 patients (95.5%). Fusion was noted in 100% of the allograft patients, whereas 90.3% of the autograft cases achieved fusion. No statistically significant difference was noted between allograft to autograft with regard to fusion rate (P > 0.05). Three patients developed nonunions (1 smoker; 2 nonsmokers) and entailed Orion instrumentation. In the one patient who was a nonsmoker with a nonunion, slight screw penetration into the involved and uninvolved interbody spaces was noted. No other intraoperative, postoperative, or radiographic complication was noted. All of the nonunions occurred early in the series. Postoperatively, excellent results were reported in 19.7%, good results in 71.2%, and fair results in 9.1% of the patients. Satisfactory clinical outcome was noted in all nonunion patients. A nonstatistically significant difference was noted with regard to clinical outcome of fused and nonfused patients, demographics, and the presence of a work-related injury (P > 0.05). The impact of smoking was not a factor influencing fusion or clinical outcome in this series (P > 0.05). A statistically significant difference was noted in plate-type on fusion rate (P < 0.05). Conclusion. A 100% and 90.3% radiographic fusion rate was obtained for allograft and autograft in one-level ACDF procedures with rigid anterior plate fixation, respectively. Although autograft achieved a higher incidence of nonunion than allograft, this may be attributed to the use of autograft early in the experience of plate application and fixation in this series. The effects of smoking were not found to be a significant factor influencing fusion in these plated patients. In 90.9% of the patients, excellent and good clinical outcome results were reported. The use of allograft in one-level ACDF with rigid plate fixation yields similar and high fusion rates as autograft. The use of allograft bone eliminates complications and pitfalls associated with autologous donor site harvesting. However, the use of autograft is a viable alternative to avoid the risk of infection, disease transmission, and histocompatibility differences associated with allograft. The use of allograft or autograft bone in properly selected patients for one-level ACDF with rigid anterior plate fixation can result in high fusion rates with excellent and good clinical outcomes.

Comparison of allograft to autograft in multilevelanterior cervical discectomy and fusion with rigid plate fixation

BACKGROUND CONTEXT A relatively high pseudarthrosis rate is associated with multilevel anterior cervical discectomy and fusion (ACDF). Anterior plate fixation increases fusion rate in multilevel ACDF. A debate still exists between the effectiveness of allograft versus autograft in plated multilevel ACDF. PURPOSE To determine the efficacy of allograft versus autograft in fusion rate and clinical outcome in patients undergoing two- and three-level ACDFs with rigid anterior plate fixation. STUDY DESIGN A retrospective radiographic and clinical review to assess fusion, risk factors and clinical outcome of 80 consecutive patients who underwent ACDF with rigid anterior plate fixation involving two and three levels with either allograft or autograft. PATIENT SAMPLE There were 45 patients (56%) who had autogenous iliac crest tricortical grafts and 35 patients (44%) who received tricortical allograft with an average age of 49 years who were treated by multilevel ACDF with rigid anterior plate fixation at a single institution. Thirty-three Peak polyaxial (Depuy-Acromed, Rayham, MA), 26 Orion (Sofamor-Danek, Memphis, TN), 16 Atlantis (Sofamor-Danek, Memphis, TN) and 5 Synthes (Paoli, PA) anterior cervical plating systems were used. All patients underwent ACDF (61 two-level, 19 three-level) by a Smith Robinson technique. All patients had burring of the end plates, 2-mm distraction of the motion segment and graft countersunk 2 mm from the anterior vertebral border. Anterior cervical plate with unicortical screw purchase was used in all cases. Segmental screw fixation was performed in 46 patients. Soft collars were worn postoperatively for 3 to 4 weeks. OUTCOME MEASURES Follow-up lateral neutral, flexion and extension radiographs were used to assess fusion. The radiographs were reviewed by an independent blinded observer in assessing fusion grades between autograft versus allograft. Clinical outcomes were rated excellent, good, fair and poor based on Odoms criteria. METHODS Fusion rate and postoperative clinical outcome were assessed in 80 patients who underwent two- or three-level ACDF with rigid anterior plate fixation. Additional risk factors were also analyzed. RESULTS Radiographic fusion was assessed in all patients (mean, 16 months). Seventy-eight patients (97.5%) achieved solid arthrodesis. Pseudarthrosis occurred in two patients who had allograft for two-level and three-level fusions. Nonsegmental screws were used in the two-level nonunion case. Postoperative dysphagia developed in one two-level nonunion patient, and revision surgery was performed in the other nonunion three-level patient. Twenty-three patients were smokers, and 26 patients had work-related injuries. Clinical outcome (mean, 20 months) was excellent in 23, good in 48 and fair in 9 patients. No statistical significance was noted between demographics, history of tobacco use, graft-type, end plate preparation technique, intermediate segmental screws, plate-type, clinical outcome of fused and nonfused patients and presence of work-related injuries (p>.05). CONCLUSIONS A high fusion rate of 97.5% was obtained for multilevel ACDF with rigid plating with either autograft or allograft. In this study, nonunion occurred in patients with allograft but this difference was not statistically significant. Fusion was obtained in 97.8% of patients with segmental screw fixation and 97.1% with nonsegmental screw fixation. Nonsegmental screw fixation may contribute to less than adequate stability and contribute to a higher rate of nonunion, but such effects could not be discerned from this study. Excellent and good clinical outcome was noted in 88.8% of the patients. Proper patient selection and meticulous operative technique is essential to obtain high fusion rates and optimal clinical outcome, which is more important than graft type.

Classification of congenitally fused cervical patterns in Klippel-Feil patients: epidemiology and role in the development of cervical spine-related symptoms.

Study Design. A retrospective cohort and series review. Objectives. To determine the role of cervical spine fusion patterns on the development of cervical spine-related symptoms (CSS) in patients with Klippel-Feil syndrome (KFS) and evaluate age- and time-dependent factors that may contribute to fused cervical patterns and the development of the CSS. Summary of Background Data. Although the “hallmark” of KFS is the presence of congenitally fused cervical vertebrae, the epidemiology and role of specific cervical fused patterns are limited. In addition, the incidence of symptoms and various age- and time-dependent factors that are directly attributed to the congenitally fused cervical segments in KFS patients is unknown. Methods. A radiographic and clinical review of 28 KFS patients at a single institution. Radiographically, Type I patients were defined as having a single congenitally fused cervical segment. Type II patients demonstrated multiple noncontiguous, congenitally fused segments, and Type III patients had multiple contiguous, congenitally fused cervical segments. Clinical records were reviewed for patient demographics, presence and type of symptoms, and clinical course. Results. Twelve males and 16 females were reviewed for clinical follow-up (mean, 8.5 years) and radiographic assessment (mean, 8.0 years). The mean age at presentation was 7.1 years; mean age of onset of CSS was 11.9 years. Clinically, 64% had no complaints referable to their cervical spine. Radiographically, 25%, 50%, and 25% were Type I, Type II, and Type III, respectively. At final clinical follow-up, 2 patients were myelopathic (Type II and Type III) and 2 were radiculopathic (Type II and Type III). Type III patients were largely asymptomatic but were associated with the highest risk in developing radiculopathy or myelopathy than Type I or Type II patients. Axial symptoms were predominantly associated with Type I patients. Myelopathic patients developed initial CSS earlier (meanage, 10.6 years) than patients with predominant axial (mean age, 13.0 years) or radiculopathic symptoms (mean age, 18.6 years) (P > 0.05). Patients with radiculopathy or myelopathy were diagnosed at a mean age of 17.9 years. Type I patients were predominantly females, while males were largely Type III. Surgery entailed 11% of patients, composed of 2 myelopathic patients (Type II and Type III) and 1 radiculopathic patient (Type II). Conclusions. In our review, 36% of KFS patients had CSS and the majority had axial symptoms. Axial neck symptoms were highly associated with Type I patients, whereas predominant radicular and myelopathic symptoms occurred in Type II and Type III patients. This classification system has promise for early detection for CSS. Activity modification should be stressed in KFS patients at high risk for neurologic compromise.

ISSLS prize winner: prevalence, determinants, and association of Schmorl nodes of the lumbar spine with disc degeneration: a population-based study of 2449 individuals.

Study Design. A cross-sectional population-based magnetic resonance imaging study of Schmorl nodes (SN) in the lumbar spine. Objective. To determine the prevalence and potential determinants of SN, and their association with intervertebral disc degeneration. Summary of Background Data. SN represent intravertebral disc herniation and are commonly seen in the spine. Their reported prevalence and determinants vary, and their association with disc degeneration remains uncertain. Data based on this large scale population-based study of intervertebral disc degeneration would provide important information for understanding SN and their pathomechanism. Methods. Sagittal T2-weighted magnetic resonance imagings of the lumbar spine were analyzed in 2449 volunteers. Two independent observers assessed the images for the presence of SN, and scored for additional radiologic features (e.g., severity of degeneration, presence of disc bulge/extrusion). Subject demographics were assessed by standardized questionnaire. Results. SN were found in 16.4% (n = 401; 219 males, 182 females; mean age = 42.3) of our study population (981 males, 1468 females; mean age = 40.4), being most common at L1/2 and L2/3 (54.1%). Multivariate logistic regression revealed that males, taller and heavier individuals had an increased likelihood of SN (P < 0.005), but association between SN and age were not discerned. Overall presence of SN was associated with disc degeneration (P < 0.001), and linearly correlated (R2 = 0.97) with increase in severity of degeneration. SN were particularly associated with severe disc degeneration at L1/2 and L2/3 with 22- to 15-fold increased odds, respectively (P < 0.0001), but less than 5-fold increased odds (P < 0.001) were noted in the lower lumbar spine. Conclusion. In a population-based cohort, 16.4% of Southern Chinese subjects had SN at 1 or more lumbar levels. Males, taller and heavier individuals had increased likelihood of SN. Interestingly, SN were highly associated with severity of disc degeneration.

Nonsurgical management of acute and chronic low back pain.

Abstract A variety of nonsurgical treatment alternatives exists for acute and chronic low back pain. Patients should receive appropriate education about the favorable natural history of low back pain, basic body mechanics, and methods (eg, exercises, activity modification, behavioral modification) that can reduce symptoms. Nonprescription medication is efficacious for mild to moderate pain. Nonsteroidal anti‐inflammatory drugs, alone or in combination with muscle relaxants, relieve pain and improve overall symptoms of acute low back pain. Exercise therapy has limited value for acute low back pain, but strong evidence supports exercise therapy in the management of chronic low back pain. Moderately strong evidence supports the use of manipulation in acute back pain. Evidence is weak for the use of epidural corticosteroid injections in patients with acute low back pain, strong for short‐term relief of chronic low back pain, and limited for long‐term relief of chronic low back pain. The use of facet injections in the management of acute low back pain is not supported by evidence, nor is the effectiveness of orthoses, traction, magnets, or acupuncture. Trigger point injections are not indicated for nonspecific acute or chronic low back pain, and sacroiliac joint injections are not indicated in the routine management of low back pain. Conflicting evidence exists regarding the use of transcutaneous electrical nerve stimulation.

Radiographic assessment of segmental motion at the atlantoaxial junction in the Klippel-Feil patient

Study Design. A retrospective review of 33 consecutive Klippel-Feil syndrome (KFS) patients at a single institution. Objectives. To assess in KFS patients the presence and degree of radiographic segmental motion at the atlantoaxial junction, factors contributing to such motion, and associated clinical manifestations. Summary of Background Data. Studies suggest that abnormal segmentation in KFS patients may result in cervical hypermobility, increasing the risk of developing neurologic compromise and the need for surgical intervention. The use of the anterior and posterior atlantodens interval (AADI/PADI) has gained interest as a method for assessing atlantoaxial instability and for space available for the cord. Although helpful for identifying instability after trauma, these measurements are not understood in KFS patients. In addition, the effects of the fusion process associated with KFS on atlantoaxial motion and associated clinical findings have not been properly addressed. Methods. Radiographs were analyzed for the presence of occipitalization, number/location of congenitally fused segments, and the AADI and PADI. Results. There were 15 males and 18 females (mean age, 13.9 years). Occipitalization occurred in 48.5% of patients. A fused C2–C3 segment was noted in 72.7% of cases. More motion with respect to AADI was evident on O–C1 and C2–C3 fusion only patients, which were all asymptomatic. Overall, 24.2% of patients were symptomatic. Mean AADI and PADI difference was 2.0 mm (symptomatic: mean, 1.5 mm; asymptomatic: mean, 2.1 mm) and −1.7 mm (symptomatic: mean, −1.0 mm; asymptomatic: mean, −2.0 mm), respectively (P > 0.05). Conclusions. Hypermobility of the atlantoaxial junction, as indicated by increased AADI on flexion-extension radiographs, is not necessarily associated with an increased risk for the development of symptoms or neurologic signs in the KFS patient. Occipitalization plays an integral role in the degree of motion at the atlantoaxial region. Greatest AADI values were in patients with occipitalization and a fused C2–C3 segment. The presence of symptoms was not related to the degree of AADI change. Evaluation of the PADI provides additional information for identifying patients at risk for developing symptoms. Nonetheless, KFS patients remain largely asymptomatic.

Current concepts in the management of metastatic spinal disease

The spine is the most frequent location for skeletal metastases[1][1] which occur in up to 40% of patients with cancer.[2][2],[3][3] The most common primary sites are the breast, prostate and lung, with involvement of 39.3%, 23.5%, and 19.9%, respectively[1][1] and with a slight male predominance.[4

Sprengel's deformity in Klippel-Feil syndrome.

Study Design. A retrospective study. Objectives. To address the role of congenitally fused cervical segments, the degree of cervical scoliosis, and other risk factors on the presence of Sprengels deformity (SD) in young patients with Klippel-Feil syndrome (KFS). Summary of Background Data. Numerous abnormalities are associated with KFS, one of the most common being SD. It has been postulated that more severe forms of KFS may be more associated with extraspinal manifestations, such as SD. Methods. Thirty KFS patients from a single institution were reviewed. Cervical neutral lateral/dynamic/ anteroposterior and thoracic anteroposterior plain radiographs were assessed. Radiographically, occipitalization (O-C1), number of congenitally fused segments (C1-T1), classification type (Types I–III), degree of cervical scoliosis, and the presence of SD was assessed. Clinical chart review entailed patient demographics and evidence of the clinical assessment of SD. The threshold for statistical significance was P < 0.05. Results. There were 11 males (36.7%) and 19 females (63.3%) with a mean age of 13.5 years (range, 2.7–26.3 years). Occipitalization was present in 10 (33.3%) individuals and C2–C3 was the most common level fused (70.0%). The mean number of congenitally fused segments was 3.3 (range, 1–6 levels). The mean degree of cervical scoliosis was 17.3° (range, 0°–67°). There were 6 (20%) Type I, 15 Type II (50.0%), and 9 Type III (30%) patients. SD was noted in 5 (16.7%) of the patients. Four patients had unilateral, whereas 1 patient had bilateral SD. There was 4.0 and 3.1 mean number of congenitally fused segments in patients with or without SD, respectively. SD did not occur in Type I patients (single fused block). The presence of SD was found to be nonsignificant regarding sex type (P = 0.327), presence of occipitalization (P = 0.300), number of congenitally fused segments (P = 0.246), specific congenitally fused segments (P > 0.05), classification type (P > 0.05), and scoliosis (P = 0.702). Conclusion. SD occurred in 16.7% of KFS patients. Sex type, number of congenitally fused segments, specific fused patterns, occipitalization, classification type, and the degree of cervical scoliosis did not seem to be significantly associated with the presence of SD in KFS patients in our series. Thorough examination for the presence and degree of SD in KFS is necessary, irrespective of the extent of cervical abnormalities. Alternatively, the treating physician should not dismiss a thorough cervical spine examination in patients with SD, evaluating factors that may predispose the KFS patient to an increased risk of neurologic injury.

Are patterns of lumbar disc degeneration associated with low back pain? New insights based on skipped level disc pathology

Study Design. A cross-sectional, population-based cohort study. Objective. The objective of this study was to evaluate the clinical relevance of skipped level disc degeneration (SLDD) to that of contiguous, multilevel disc degeneration (CMDD) of the lumbar spine. The study also aimed to identify patterns of SLDD, its classification, prevalence, and clinical relevance. Summary of Background Data. The association of disc degeneration on magnetic resonance imaging with low back pain (LBP) remains questionable. The occurrence of SLDD of the lumbar spine has recently been noted. To date, patterns of disc degeneration have been overlooked in the association with low back symptoms. Methods. A population-based radiographic and clinical study of 3099 Southern Chinese patients. Individuals with multilevel disc degeneration of the lumbar spine on sagittal T2-weighted magnetic resonance imaging (N = 1457) were stratified to SLDD (n = 301; 20.7%) or CMDD (n = 1156; 79.3%) groups. SLDD was further classified into 5 types by the relative location of nondegenerated normal disc(s) to degenerated disc levels. Subject demographics, presence of LBP, pain intensity, and functional disability were assessed. Results. In the multivariate analyses, CMDD increased the likelihood of historical LBP (odds ratio [OR]: 1.39; 95% confidence interval [CI]: 1.00–1.93; P = 0.047) and pain severity (OR: 1.83; 95% CI: 1.23–2.73; P = 0.003) in comparison with SLDD. A significant increasing trend of number of levels with disc degeneration, overall disc degeneration severity, and presence of disc bulges/extrusions was noted from SLDD type I (least severe) to SLDD type V (most severe) (P < 0.05). A higher prevalence of LBP and a higher pain intensity were observed in SLDD classification type V. Functional disability scores did not differ between CMDD and SLDD, nor within SLDD classification types (P > 0.05). Conclusion. Our large-scale study is the first to describe novel variants of SLDD types and their clinical relevance. More important, LBP and severity of pain were more pronounced in individuals with CMDD rather than those with SLDD. Our study suggests that subjects with a similar degree but different patterns of multilevel disc degeneration do differ with respect to low back symptoms. This finding may provide new evidence with regard to the mechanism of LBP.

Multiple and simultaneous spine fractures in ankylosing spondylitis: Case report

Study Design. A case report. Objective. To report the unique occurrence and treatment of multiple and simultaneous spine fractures in a patient with progressed ankylosing spondylitis and preexisting multilevel spine instrumentation. Summary of Background Data. Ankylosing spondylitis is a complex inflammatory arthritic condition that renders the spine more susceptible to fracture than individuals who do not have ankylosing spondylitis. To our knowledge, in the patient with ankylosing spondylitis, the occurrence of nonregion-specific multiple and simultaneous spine fractures, and the role of internal instrumentation in subsequent fracture development have not been addressed in the literature. Methods. An 81-year-old white male with ankylosing spondylitis had 2 low-energy falls, resulting in 3 spine fractures. During the first fall, he had a displaced fracture at the T11–T12 level without a spinal cord injury. Fracture treatment entailed posterior instrumentation with fusion at T8-L2 and immobilization after surgery with a thoracolumbosacral orthosis brace, which led to successful healing of the injury. Approximately 2 years later, the patient had a second fall, and presented with simultaneous displaced fractures at the C6–C7 and L2–L3 levels, and an American Spinal Injury Association-A spinal cord injury. The cervical and lumbar fractures were both treatedoperatively via a 2-staged approach with posterior segmental instrumentation and fusion at C3–T3 and at L2–L5, respectively. A soft cervical collar and a thoracolumbosacral orthosis brace were worn after surgery. There were no intraoperative complications. Results. Although anatomic reduction and stable fixation of the spinal injuries were achieved, the patient’s neurologic status following the second injury remained unchanged. His postoperative course was complicated by pulmonary failure that ultimately resulted in death by the 3-month postoperative time. Conclusions. Patients with ankylosing spondylitis have a strong susceptibility to spine fracture from minor trauma, which can have devastating outcomes. Nonregion-specific multiple and simultaneous spine fractures can occur, and require thorough radiographic evaluation with imaging of the entire spinal axis, appropriate operative planning, and meticulous perioperative treatment. Preexisting internal spine instrumentation may predispose the ankylosing spondylitis spine to multiple fractures, even following a minor traumatic event. As such, the clinician should be cognizant of the possible existence of multiple and simultaneous fractures in patients with ankylosing spondylitis with preexisting internal spine instrumentation.