Tophaceous gout of the atlantoaxial joint: a case report.

BACKGROUND: To report the occurrence of tophaceous gout in the cervical spine and to review the literature on spinal gout. CASE PRESENTATION: This report details the occurrence of a large and clinically significant finding of tophaceous gout in the atlantoaxial joint of the cervical spine in an 82-year-old Caucasian man with a 40-year history of crystal-proven gout and a 3-month history of new-onset progressive myelopathy. The patient's American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) criteria score was 15.0. CONCLUSION: Spinal gout is more common than previously thought, and it should be considered in patients who present with symptoms of myelopathy. Diagnosis can be made without a tissue sample of the affected joint(s) with tools like the ACR/EULAR criteria and the use of the "diagnostic clinical rule" for determining the likelihood of gout. Early conservative management with neck immobilization and medical management can avoid the need for surgical intervention.

Neuropathic Arthropathy of the Shoulder: A Systematic Review of Classifications and Treatments.

BACKGROUND: Neuropathic arthropathy of the shoulder is a chronic progressive process characterized by joint destruction in the presence of a neurosensory deficit. Causes include syringomyelia, syphilis, diabetes, chronic alcoholism, and leprosy, with syringomyelia accounting for the vast majority of upper-extremity Charcot joints. Early presentation of this rare condition includes nonspecific symptoms such as swelling, erythema, sensory symptoms, and decreased functionality, making diagnosis challenging. METHODS: We systematically reviewed 32 case reports published between 1924 and 2016. A total of 59 shoulders from 56 patients are included in this analysis. Variables include patient demographic characteristics, presentation, etiology, diagnostic techniques, treatment, outcome, and follow-up of Charcot shoulder. RESULTS: We compiled a total of 25 right shoulders (42%), 24 left shoulders (41%), and 10 shoulders (17%) with unspecified laterality. The mean patient age (and standard deviation) was 49 ± 11 years, and the median age was 47 years. There was a higher prevalence in men (37 shoulders [63%]) compared with women (22 shoulders [37%]). Presenting symptoms included reduced range of motion (53 shoulders [90%]), paresthesia or hypoesthesia (45 [76%]), swelling (44 [75%]), weakness (40 [68%]), pain (31 [53%]), and reduction in deep tendon reflexes (22 [37%]). Shoulder radiographs were made in all cases. The presence of a syrinx was detected in 45 shoulders (76%) with magnetic resonance imaging, myelography, or clinical diagnosis. Sixteen shoulders (27%) reported exposure to trauma, with a 69% decrease in time from presentation to diagnosis compared with non-traumatic cases. Treatment was categorized as solely nonoperative management (14 [24%]), operative management (13 [22%]), combined therapy (20 [34%]), and no treatment listed (10 [17%]). Two surgical cases (3%) were excluded from our treatment group analysis as they were treated for unrelated or misdiagnosed conditions. CONCLUSIONS: Our study increases awareness and understanding of this complex, progressive disease to reduce delay and misdiagnosis and to contribute to the standard-of-care recommendations. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A comparison C1-C2 transarticular screw placement after self-education and mentored education of orthopaedic residents.

STUDY DESIGN: Prospective randomized trial. OBJECTIVE: This study will provide preliminary data on whether residents can be "self-taught" and to what extent a lecture, demonstration, and coaching can improve skills and knowledge. BACKGROUND DATA: Practice-based learning is an essential competency in Accreditation Council for graduate Medical Education-accredited residencies. Little has been done to demonstrate whether residents can be self-taught or benefit from mentoring in understanding and performing difficult surgical tasks. METHODS: A written test was given to orthopedic residents on C1-C2 transarticular screw placement. They were then provided reading on C1-C2 transarticular screw placement. Residents were then divided into a "self-directed learning" group and a "mentored learning" group. All residents then performed the technique on models, with the "mentored" group receiving a lecture and coaching from the mentor. The models were analyzed for technique errors and the previous test was administered again as a posttest. The test and screw placement were repeated 4 months later. RESULTS: Residents without mentoring had an average improvement of 4.5 points, those with mentoring had average improvement of 8.6 points (P=0.0068). The screw placement technique error rate for the nonmentored group (n=8) was 2.55, and for the mentored group (n=9) was 1.47 (P=0.004). Sixteen residents completed the delayed test, 7 from the nonmentored groups and 8 from the mentored group. Nine residents were able to repeat the screw placement technique 4 months after the initial test and screw placement, 3 nonentored, and 6 mentored. Although there were some trends toward the mentored group having better retention, neither knowledge nor skill was statistically different. CONCLUSIONS: This preliminary trial seems to indicate that residents provided a lecture and guided technical instruction will obtain knowledge and perform procedures better than those that do not. Conclusions based upon Post Graduate year, motivation, and interest in spine surgery could not be made.

Bone void fillers.

For this technology overview, the tools of evidence-based medicine were used to summarize information on the effectiveness and clinical outcomes related to the usage of bone void fillers- specifically, synthetic graft materials. Comprehensive literature searches were conducted to address five key questions, which the task force that prepared the report posed as follows. Question 1 addressed the use of synthetic bone void fillers alone. Question 2 was designed to determine whether synthetic bone void fillers could successfully serve as graft extenders and eliminate the need for iliac crest bone graft. Questions 3, 4, and 5 addressed the use of allografts as a comparison with synthetic fillers because clinical results with allografts are perceived as being much closer to autografts in these areas of the spine.

Debating the value of spine surgery.

Lumbar arthrodesis is a commonly performed operative procedure for the treatment of low back pain. Recently, total disc arthroplasty has gained some acceptance among surgeons and patients. However, the indications for and results of back pain surgery remain controversial and confusing. Available information suggests that meaningful functional improvement from these procedures is debatable and that the cost of such elective operations is high. Currently, lumbar disc replacement has gained minimal support from governmental and private payers. Among those attending this symposium at the 2009 Annual Meeting of the AOA, the vast majority concurred that Medicare and private insurance should not necessarily pay for disc replacement surgery. Interestingly, among this skeptical group of orthopaedic surgeons, only 23% believed that degeneration of the intervertebral disc is the major cause of low back pain. When asked the hypothetical question, "If you experienced chronic low back pain with degenerative changes at one level, what course of treatment would you opt for?" 61% responded that they would choose nonoperative treatment and 38%, that they would choose no treatment. Of more than 100 respondents, only one responded that he or she would undergo fusion and one admitted a willingness to undergo disc replacement in this hypothetical scenario.

Measurement of a posterior occipitocervical fusion angle.

STUDY DESIGN: A method for evaluating occipitocervical neutral position is described. OBJECTIVE: To describe and measure a posterior occipitocervical angle (POCA) in normal subjects that can be used to guide contouring of fusion implants to achieve occipitocervical neutral fusion and for use in standardized testing of occipitocervical constructs. SUMMARY OF BACKGROUND DATA: The goal of occipitocervical fusion is to fuse the head in an ideal functional position. Several methods of estimating occipitocervical neutral position have been described and tested, yet none has been proven superior. An ideal method would easily and reproducibly aid in evaluating occipitocervical position intraoperatively and potentially aid in the design and testing of implant constructs. METHODS: Fifteen adult lateral cervical spine radiographs taken in occipitocervical neutral position and interpreted as normal by an experienced radiologist were studied. Analysis consisted of measurement of the POCA. The POCA is defined as the angle formed by the intersection of a line drawn tangential to the posterior aspect of the occipital protuberance and a line determined by the posterior aspect of the facets of the third and fourth cervical vertebrae. RESULTS: The mean POCA was 109.7 degrees with a SD of 5.7 degrees. Compilation of the data revealed a normal distribution of measurements where 80% of the POCA values were between 101 and 119 degrees. CONCLUSIONS: POCA is a simple measurement that may be valuable as an intraoperative tool during occipitocervical fusion and may aid the design and testing of fusion implants and their application in the operating room.

The FDA process for the evaluation and approval of orthopaedic devices.

The US Food and Drug Administration (FDA) is a scientific, regulatory, and public health agency whose authority includes overseeing the marketing of products relevant to medical practice. Devices are classified based on the extent of oversight needed to ensure public safety. Divisions within the FDA provide specific expertise regarding drugs, devices, biologic products, and combinations thereof. Various pathways exist to apply for marketing through the FDA, depending on the nature of the product and its intended use. Expert panels advise the agency on issues related to product safety and efficacy, and clinical studies may be required to provide data based on these parameters. Clinical data are monitored postapproval for potential adverse events not evident in earlier trials. Orthopaedic surgeons are involved in all aspects of the FDA as employees, consultants, product advocates, participants in clinical trials and advisory panels, and experts involved in the appropriate reporting of adverse events.

The ability of MRI to predict failure of nonoperative treatment of pyogenic vertebral osteomyelitis.

Pyogenic vertebral osteomyelitis (PVO) can be treated most often by medical management. For those failing with medical management, surgical delay can result in increased morbidity. Therefore, the ability to predict failure of medical management on presentation would greatly improve the outcome. This study determines the ability of the presenting magnetic resonance imaging scan to predict failure of nonoperative management at the onset of treatment. A cohort of patients with PVO, initially treated medically, was reviewed. Imaging, demographics, and clinical data of patients successfully treated medically were compared with those ultimately requiring surgical treatment. The extent of signal change on the T1-weighted sagittal images of the affected motion segment was determined for each group. Twenty-two patients were included in the study. Patients successfully treated medically averaged 57%+/-19% of motion segment involvement, whereas those failing conservative treatment averaged 89%+/-18%. Using 90% involvement as an indication for initial surgery would have a sensitivity of 78% and specificity of 93%. Patients with thoracolumbar PVO who have 90% or higher involvement of an affected motion segment should be considered for early operative management.

Short segment fixation of thoracolumbar burst fractures.

Short segment instrumentation for thoracolumbar fractures or fracture dislocations continues to be controversial. Recently, a load-sharing classification score was developed to help predict failure of posterior instrumented fusion alone used for highly comminuted and kyphotic fractures. Twenty-two patients treated with short-segment posterior instrumentation for thoracolumbar fractures were retrospectively reviewed. Although posterior instrumented fusion was used for fractures with a relatively high load sharing classification score, the load-sharing classification score was not predictive of posterior instrumentation failure. Single-level cephalad instrumentation failed at a higher rate than two-level cephalad instrumentation.

Corrosion on spinal implants.

OBJECTIVE: Modular spine implants are used as an aid to obtaining fusion, but fretting and corrosion occur between modular components in a biologic environment. METHODS: Forty-eight spinal implant constructs manufactured by a variety of companies were retrieved from 47 patients and were subjected to surface analysis stereomicroscopy. RESULTS: Stainless-steel implants (n = 23) had either semirigid constructs with mild or no surface alteration (n = 7) or rigid constructs with moderate or severe alteration (n = 16). Surface damage was consistent with previously observed mechanically assisted crevice corrosion phenomena. Titanium alloy implants (n = 25) showed no significant corrosion but had three constructs with fatigue failure of anchoring screws. One cobalt alloy construct showed no evidence of corrosion. CONCLUSIONS: Long-term effects of fretting and corrosion are unclear, and minimization of these phenomena seems justified. Selection of modular components with similar materials and surface finish may help the surgeon minimize localized changes over time. Stainless-steel implants with rigid interconnections and those with different surface finishes between rods and connectors are most susceptible to corrosion.

Cervical spine injury and restraint system use in motor vehicle collisions.

CONTEXT: Cervical spine injury related to motor vehicle collision (MVC) is a severe and often permanently disabling injury. Although advances in automobile crashworthiness have reduced both fatalities and some severe injuries, the impact of varying occupant restraint systems (seatbelts and airbags) on cervical spine injury is unknown. OBJECTIVE: To investigate the relationship between the occurrence of cervical spine injury and occupant restraint systems among front seat occupants involved in frontal MVCs. DESIGN, SETTING, AND PATIENTS: A case-control study among subjects obtained from the 1995 to 2001 National Automotive Sampling System (NASS). Cases were identified based on having sustained a cervical spine injury score of 2 or more on the Abbreviated Injury Scale, 1990 Revision. RESULTS: Approximately half (44.7%) of 8,412 cases of cervical spine injury were unrestrained occupants while belted only, airbag only, and both restraint systems represented 38.2%, 8.8%, and 8.4% of cases, respectively. Overall, the combined use of airbag and seatbelt had the greatest protective effect, relative to unrestrained occupants, with an odds ratio (OR) of 0.19 and a 95% confidence interval (CI) of 0.12 to 0.30. Use of a seatbelt only also had a protective effect (OR: 0.40; 95% CI: 0.23-0.70). Occupant use of an airbag only neither increased nor decreased the risk of cervical spine injuries relative to unrestrained occupants (OR: 1.02; 95% CI: 0.57-2.13). CONCLUSIONS: The results of this study suggest that there is an increase in overall protection against cervical spine injury by combining airbag and seatbelt restraint systems relative to seatbelt alone.

Thoracolumbar fracture management: anterior approach.

The surgeon who treats patients with spine trauma must be able to apply a variety of management techniques to achieve optimal care of the patient. The anterior surgical approach is appropriate for some thoracolumbar burst fractures in patients with neurologic deficit and without posterior ligamentous injury. Surgery is most often indicated for patients with incomplete deficit, especially those with a large retropulsed fragment, marked canal compromise, severe anterior comminution, or kyphosis <30 degrees. This approach provides excellent visualization of the anterior aspect of the dura mater for decompression. Reconstruction of the anterior body defect can be done with autograft, allograft, or a cage. Supplementation of the graft with anterior internal fixation helps prevent kyphosis. Clinical results demonstrate improved neurologic function in most patients as well as low pseudarthrosis rates. In patients with incomplete deficit, improvement in neurologic function usually can be expected with few complications.

The acute effects of posterior fusion instrumentation on kinematics and intradiscal pressure of the human lumbar spine.

Nine cadaver lumbar spines were analyzed by applying nonconstraining nondestructive bending moments while measuring global range of motion, mechanical reaction at the sacrum, applied moment at the top of the specimen, segmental range of motion at L1-L5, and IDP at L1-L4. Each specimen was examined in an intact and instrumented state (with L3-L4 posterior instrumentation) using range of motion-based biomechanical testing, while achieving a similar global ROM in the sagittal, frontal, and transverse planes. An increase in applied moment was required during instrumented testing when compared with intact, and a significant increase in segmental range of motion during instrumented testing was found at all uninstrumented levels. Significant decreases in segmental range of motion were measured at the instrumented level when compared with intact testing. The most significant decreases and increases in IDP occurred at the instrumented level during sagittal and transverse plane testing.