Christopher M. Bono

A New Classification of Thoracolumbar Injuries: The Importance of Injury Morphology, the Integrity of the Posterior Ligamentous Complex, and Neurologic Status

Study Design. A new proposed classification system for thoracolumbar (TL) spine injuries, including injury severity assessment, designed to assist in clinical management. Objective. To devise a practical, yet comprehensive, classification system for TL injuries that assists in clinical decision-making in terms of the need for operative versus nonoperative care and surgical treatment approach in unstable injury patterns. Summary of Background Data. The most appropriate classification of traumatic TL spine injuries remains controversial. Systems currently in use can be cumbersome and difficult to apply. None of the published classification schemata is constructed to aid with decisions in clinical management. Methods. Clinical spine trauma specialists from a variety of institutions around the world were canvassed with respect to information they deemed pivotal in the communication of TL spine trauma and the clinical decision-making process. Traditional injury patterns were reviewed and reconsidered in light of these essential characteristics. An initial validation process to determine the reliability and validity of an earlier version of this system was also undertaken. Results. A new classification system called the Thoracolumbar Injury Classification and Severity Score (TLICS) was devised based on three injury characteristics: 1) morphology of injury determined by radiographic appearance, 2) integrity of the posterior ligamentous complex, and 3) neurologic status of the patient. A composite injury severity score was calculated from these characteristics stratifying patients into surgical and nonsurgical treatment groups. Finally, a methodology was developed to determine the optimum operative approach for surgical injury patterns. Conclusions. Although there will always be limitations to any cataloging system, the TLICS reflects accepted features cited in the literature important in predicting spinal stability, future deformity, and progressive neurologic compromise. This classification system is intended to be easy to apply and to facilitate clinical decision-making as a practical alternative to cumbersome classification systems already in use. The TLICS may improve communication between spine trauma physicians and the education of residents and fellows. Further studies are underway to determine the reliability and validity of this tool.

Low-Back Pain in Athletes

While most occurrences of low-back pain in athletes are self-limited sprains or strains, persistent, chronic, or recurrent symptoms are frequently associated with degenerative lumbar disc disease or spondylolytic stress lesions. The prevalence of radiographic evidence of disc degeneration is higher in athletes than it is in nonathletes; however, it remains unclear whether this correlates with a higher rate of back pain. Although there is little peer-reviewed clinical information on the subject, it is possible that chronic pain from degenerative disc disease that is recalcitrant after intensive and continuous nonoperative care can be successfully treated with interbody fusion in selected athletes. In general, the prevalence of spondylolysis is not higher in athletes than it is in nonathletes, although participation in sports involving repetitive hyperextension maneuvers, such as gymnastics, wrestling, and diving, appears to be associated with disproportionately higher rates of spondylolysis. Nonoperative treatment of spondylolysis results in successful pain relief in approximately 80% of athletes, independent of radiographic evidence of defect healing. In recalcitrant cases, direct surgical repair of the pars interarticularis with internal fixation and bone-grafting can yield high rates of pain relief in competitive athletes and allow a high percentage to return to play. Sacral stress fractures occur almost exclusively in individuals participating in high-level running sports, such as track or marathon. Treatment includes a brief period of limited weight-bearing followed by progressive mobilization, physical therapy, and return to sports in one to two months, when the pain has resolved.

Critical analysis of trends in fusion for degenerative disc disease over the past 20 years: influence of technique on fusion rate and clinical outcome.

Study Design. Critical analysis of the results reported in published literature. Objectives. The purpose of this study was to evaluate whether various technical advancements have affected the outcome of lumbar spinal fusion for degenerative disease by critically analyzing the available literature from the past two decades. Summary of Background Data. To improve fusion rate and clinical outcome, various surgical options for lumbar spinal fusion for degenerative disc disorders have been introduced over the past 20 years. However, an important fundamental question still remains: What has been the impact of these new techniques and innovations on surgical results? Methods. A comprehensive computer search of the English literature from 1979 to 2000 concerning lumbar/lumbosacral spinal fusion was performed using the keywords degenerative, lumbar, and fusion. Results. Numerous deficiencies were noted in the reviewed literature. Nearly half of the studies failed to specify methodologic design, and documentation of brace use, graft source, fusion location, and fusion rate was missing in 38, 10, 2, and 4 of the 84 articles reviewed, respectively. From the data gathered, a noticeable trend toward the increasing use of internal fixation was noted, accounting for 23% of fusions in the 1980s versus 41% in the 1990s. Despite this trend, an improvement in overall fusion rate or clinical outcome could not be demonstrated. Conclusions. Numerous technologic advancements in lumbar spine fusion have been made over the past 20 years. Future advances in care are dependent on review of reported results. The numerous deficiencies detected in the analyzed literature herald the necessity for a uniform system of outcomes reporting containing a core of critical demographic, perioperative, and postsurgical information. Although a shift toward a greater use of technology was noted in the published literature, the clinical benefit of this trend remains unclear.

Lumbar Adjacent Segment Degeneration and Disease After Arthrodesis and Total Disc Arthroplasty

Study Design. Systematic review of published incidence of radiographic adjacent segment degeneration (ASDeg) and symptomatic adjacent segment disease (ASDis) after arthrodesis or total disc replacement. Objective. Assess impact of surgery method and other factors on the incidence of ASDeg and ASDis. Summary of Background Data. Twenty-seven articles, none of which were class I or II, met the inclusion criteria. Twenty involved arthrodesis (1732 patients) and 7 involved arthroplasty (758 patients). Nineteen detailed ASDeg and 16 detailed ASDis. Methods. Data were established for number of patients, gender, average patient age, incidence of ASDeg and ASDis, average time to follow-up, and level and type of surgery. Multivariate logistic regression was used to identify which parameters had a significant effect on the incidence of ASDeg and ASDis. Results. Three hundred fourteen of 926 patients in the arthrodesis group (34%) and 31 out of 313 patients in the total disc replacement group (9%) developed ASDeg. (P < 0.0001) Multivariate logistic regression indicated that higher odds of ASDeg were associated with: older patients (P < 0.001); arthodesis (P = 0.0008); and longer follow-up (P = 0.0025). For ASDis, 173/1216 (14%) arthrodesis patients developed ASDis compared to 7/595 (1%) of arthroplasty patients (P < 0.0001). Using multivariate logistic regression, higher odds of ASDis were seen in studies with fusion (P < 0.0001), higher percentages of male patients (P = 0.0019), and shorter follow-up (P < 0.05). Conclusion. Analysis of the literature suggests a correlation between fusion and the development of ASDeg compared to arthroplasty, but this association is dampened by the influence of patient age. There is a stronger correlation between fusion and ASDis compared to arthroplasty. The data supports only a class C recommendation (lowest tier) for the use of arthroplasty to reduce ASDis and disc degeneration compared to arthrodesis.

Operative compared with nonoperative treatment of a thoracolumbar burst fracture without neurological deficit: a prospective randomized study with follow-up at sixteen to twenty-two years.

Background: To our knowledge, a prospective, randomized study comparing operative and nonoperative treatment of a thoracolumbar burst fracture in patients without a neurological deficit has never been performed. Our hypothesis was that operative treatment would lead to superior long-term clinical outcomes. Methods: From 1994 to 1998, forty-seven consecutive patients (thirty-two men and fifteen women) with a stable thoracolumbar burst fracture and no neurological deficit were randomized to one of two treatment groups: operative (posterior or anterior arthrodesis and instrumentation) or nonoperative treatment (application of a body cast or orthosis). Radiographs and computed tomography scans were analyzed for sagittal alignment and canal compromise. All patients completed a questionnaire to assess any disability they may have had before the injury, and they indicated the degree of pain at the time of presentation with use of a visual analog scale. The average duration of follow-up was forty-four months (minimum, twenty-four months). After treatment, patients indicated the degree of pain with use of the visual analog scale and they completed the Roland and Morris disability questionnaire, the Oswestry back-pain questionnaire, and the Short Form-36 (SF-36) health survey. Results: In the operative group (twenty-four patients), the average fracture kyphosis was 10.1° at the time of admission and 13° at the final follow-up evaluation. The average canal compromise was 39% on admission, and it improved to 22% at the final follow-up examination. In the nonoperative group (twenty-three patients), the average kyphosis was 11.3° at the time of admission and 13.8° at the final follow-up examination after treatment. The average canal compromise was 34% at the time of admission and improved to 19% at the final follow-up examination. On the basis of the numbers available, no significant difference was found between the two groups with respect to return to work. The average pain scores at the time of the latest follow-up were similar for both groups. The preinjury scores were similar for both groups; however, at the time of the final follow-up, those who were treated nonoperatively reported less disability. Final scores on the SF-36 and Oswestry questionnaires were similar for the two groups, although certain trends favored those treated without surgery. Complications were more frequent in the operative group. Conclusion: We found that operative treatment of patients with a stable thoracolumbar burst fracture and normal findings on the neurological examination provided no major long-term advantage compared with nonoperative treatment. Level of Evidence: Therapeutic study, Level II-2 (poor-quality randomized controlled trial [e.g., <80% follow-up]). See Instructions to Authors for a complete description of levels of evidence.

Efficacy and safety of surgical decompression in patients with cervical spondylotic myelopathy: results of the AOSpine North America prospective multi-center study.

BACKGROUND Cervical spondylotic myelopathy is the leading cause of spinal cord dysfunction worldwide. The objective of this study was to evaluate the impact of surgical decompression on functional, quality-of-life, and disability outcomes at one year after surgery in a large cohort of patients with this condition. METHODS Adult patients with symptomatic cervical spondylotic myelopathy and magnetic resonance imaging evidence of spinal cord compression were enrolled at twelve North American centers from 2005 to 2007. At enrollment, the myelopathy was categorized as mild (modified Japanese Orthopaedic Association [mJOA] score ≥ 15), moderate (mJOA = 12 to 14), or severe (mJOA < 12). Patients were followed prospectively for one year, at which point the outcomes of interest included the mJOA score, Nurick grade, Neck Disability Index (NDI), and Short Form-36 version 2 (SF-36v2). All outcomes at one year were compared with the preoperative values with use of univariate paired statistics. Outcomes were also compared among the severity classes with use of one-way analysis of variance. Finally, a multivariate analysis that adjusted for baseline differences among the severity groups was performed. Treatment-related complication data were collected and the overall complication rate was calculated. RESULTS Eighty-five (30.6%) of the 278 enrolled patients had mild cervical spondylotic myelopathy, 110 (39.6%) had moderate disease, and 83 (29.9%) had severe disease preoperatively. One-year follow-up data were available for 222 (85.4%) of 260 patients. There was a significant improvement from baseline to one year postoperatively (p < 0.05) in the mJOA score, Nurick grade, NDI score, and all SF-36v2 health dimensions (including the mental and physical health composite scores) except general health. With the exception of the change in the mJOA, the degree of improvement did not depend on the severity of the preoperative symptoms. These results remained unchanged after adjusting for relevant confounders in the multivariate analysis. Fifty-two patients experienced complications (prevalence, 18.7%), with no significant differences among the severity groups. CONCLUSIONS Surgical decompression for the treatment of cervical spondylotic myelopathy was associated with improvement in functional, disability-related, and quality-of-life outcomes at one year of follow-up for all disease severity categories. Furthermore, complication rates observed in the study were commensurate with those in previously reported cervical spondylotic myelopathy series.

Perioperative and delayed complications associated with the surgical treatment of cervical spondylotic myelopathy based on 302 patients from the AOSpine North America Cervical Spondylotic Myelopathy Study

OBJECT Rates of complications associated with the surgical treatment of cervical spondylotic myelopathy (CSM) are not clear. Appreciating these risks is important for patient counseling and quality improvement. The authors sought to assess the rates of and risk factors associated with perioperative and delayed complications associated with the surgical treatment of CSM. METHODS Data from the AOSpine North America Cervical Spondylotic Myelopathy Study, a prospective, multicenter study, were analyzed. Outcomes data, including adverse events, were collected in a standardized manner and externally monitored. Rates of perioperative complications (within 30 days of surgery) and delayed complications (31 days to 2 years following surgery) were tabulated and stratified based on clinical factors. RESULTS The study enrolled 302 patients (mean age 57 years, range 29-86) years. Of 332 reported adverse events, 73 were classified as perioperative complications (25 major and 48 minor) in 47 patients (overall perioperative complication rate of 15.6%). The most common perioperative complications included minor cardiopulmonary events (3.0%), dysphagia (3.0%), and superficial wound infection (2.3%). Perioperative worsening of myelopathy was reported in 4 patients (1.3%). Based on 275 patients who completed 2 years of follow-up, there were 14 delayed complications (8 minor, 6 major) in 12 patients, for an overall delayed complication rate of 4.4%. Of patients treated with anterior-only (n = 176), posterior-only (n = 107), and combined anterior-posterior (n = 19) procedures, 11%, 19%, and 37%, respectively, had 1 or more perioperative complications. Compared with anterior-only approaches, posterior-only approaches had a higher rate of wound infection (0.6% vs 4.7%, p = 0.030). Dysphagia was more common with combined anterior-posterior procedures (21.1%) compared with anterior-only procedures (2.3%) or posterior-only procedures (0.9%) (p < 0.001). The incidence of C-5 radiculopathy was not associated with the surgical approach (p = 0.8). The occurrence of perioperative complications was associated with increased age (p = 0.006), combined anterior-posterior procedures (p = 0.016), increased operative time (p = 0.009), and increased operative blood loss (p = 0.005), but it was not associated with comorbidity score, body mass index, modified Japanese Orthopaedic Association score, smoking status, anterior-only versus posterior-only approach, or specific procedures. Multivariate analysis of factors associated with minor or major complications identified age (OR 1.029, 95% CI 1.002-1.057, p = 0.035) and operative time (OR 1.005, 95% CI 1.002-1.008, p = 0.001). Multivariate analysis of factors associated with major complications identified age (OR 1.054, 95% CI 1.015-1.094, p = 0.006) and combined anterior-posterior procedures (OR 5.297, 95% CI 1.626-17.256, p = 0.006). CONCLUSIONS For the surgical treatment of CSM, the vast majority of complications were treatable and without long-term impact. Multivariate factors associated with an increased risk of complications include greater age, increased operative time, and use of combined anterior-posterior procedures.

Interspinous Process Devices in the Lumbar Spine

A growing number of interspinous process devices have been introduced to the lumbar spine implant market. Implant designs vary from static spacers to dynamized devices. Furthermore, they are composed of a range of different materials including bone allograft, titanium, polyetheretherketone, and elastomeric compounds. The common link between them is the mechanical goal of distracting the spinous processes to affect the intervertebral relationship. In contrast, the purported clinical goals are more variable, ranging from treatment of degenerative spinal stenosis, discogenic low back pain, facet syndrome, disk herniations, and instability. Though some clinical data exist for some of these devices, defining the indications for these minimally invasive procedures will be crucial. Indications should emerge from thoughtful consideration of data from randomized controlled studies.

Radial and axillary nerves: Anatomic considerations for humeral fixation

Because the axillary and radial nerves can be injured during operative exposure and fixation of the humerus, accurate delineation of their location is vital to avoid complications. The authors investigated the relationship of the radial and axillary nerves for radiographically and surgically identifiable bony landmarks. Fifty fresh human cadaveric upper extremities were dissected to identify the nerves as they crossed the lateral intermuscular septum and the humeral surgical neck, respectively. Longitudinal distances between the nerves and the superior aspect of the humeral head, the surgical neck, the superior extent of the olecranon fossa, and the distal aspect of the trochlea were measured with calipers. The average distance from the axillary nerve to the proximal humerus was 6.1 ± 0.7 cm (range, 4.5-6.9 cm) and 1.7 ± 0.8 cm (range, 0.7-4.0 cm) from the surgical neck. The radial nerve traversed the lateral intermuscular septum 17 ± 2.3 cm (range, 13-22 cm) from the proximal humerus, 12 ± 2.3 cm (range, 7.4-16.6 cm) from the olecranon fossa, and 16 ± 0.4 cm (range, 9.0-20.5 cm) from the distal humerus, representing the approximate midpoint of the bone. Anteroposterior locking screws placed into the proximal humerus endanger the axillary nerve because it lies directly over the posterior cortex as little as 0.7 cm from the surgical neck. As the radial nerve crosses the lateral intermuscular septum more proximal than generally was thought, it is at risk during implant insertion in the distal half of the humerus. Using measurements calculated from preoperative and intraoperative imaging, the approximate position of the nerve could be determined to better plan fixation method and implant location.

Gunshot wounds to the spine

BACKGROUND CONTEXT The incidence of violent crimes has risen over the past decade. With it, gunshot injuries have become increasingly more common in the civilian population. Among the most devastating injuries are gunshot wounds to the spine. PURPOSE The purpose of this article is to provide a thorough review of the pathomechanics, diagnosis and treatment of gunshot wounds to the spine. STUDY DESIGN/SETTING Literature review article. CONCLUSIONS Treatment of gunshot spine fractures differs from other mechanisms. Fractures are usually inherently stable and rarely require stabilization. In neurologically intact patients, there are few indications for surgery. Evidence of acute lead intoxication, an intracanal copper bullet or new onset neurologic deficit can justify operative decompression and/or bullet removal. Overzealous laminectomy can destabilize the spine and lead to late postoperative deformity. For complete and incomplete neural deficits at the cervical and thoracic levels, operative decompression is of little benefit and can lead to higher complication rates than nonsurgically managed patients. With gunshots to the T12 to L5 levels, better motor recovery has been reported after intracanal bullet removal versus nonoperative treatment. The use of steroids for gunshot paralysis has not improved the neurologic outcome and has resulted in a greater frequency of nonspinal complications. Although numerous recommendations exist, 7 to 14 days of broad-spectrum antibiosis has lead to the lowest rates of infection after transcolonic gunshots to the spine.