Quantifying Patient Expectations for Total Knee Arthroplasty: Expectations for Improvement Are Greater Than Minimal Clinically Important Difference.

BACKGROUND: Achieving a minimal clinically important difference (MCID) in patient-reported outcomes following total knee arthroplasty (TKA) is common, yet up to 20% patient dissatisfaction persists. Unmet expectations may explain post-TKA dissatisfaction. No prior studies have quantified patient expectations using the same patient-reported outcome metric as used for MCID to allow direct comparison. METHODS: This was a prospective study of patients undergoing TKA with 5 fellowship-trained arthroplasty surgeons at one academic center. Baseline Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference (PI) domains were assessed. Expected PROMIS scores were determined by asking patients to indicate the outcomes they were expecting at 12 months postoperatively. Predicted scores were generated from a predictive model validated in the Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement (FORCE-TJR) dataset. T-tests were used to compare baseline, expected, and predicted PROMIS scores. Expected scores were compared to PROMIS MCID values obtained from the literature. Regression models were used to identify patient characteristics associated with high expectations. RESULTS: There were 93 patients included. Mean age was 67 years (range, 30 to 85) and 55% were women. Mean baseline PROMIS PF and PI was 34.4 ± 6.7 and 62.2 ± 6.4, respectively. Patients expected significant improvement for PF of 1.9 times the MCID (MCID = 11.3; mean expected improvement = 21.6, 95% confidence interval [CI] 19.6 to 23.5, P < .001) and for PI of 2.3 times the MCID (MCID = 8.9; mean expected improvement = 20.6, 95% CI 19.1-22.2, P < .001). Predicted scores were significantly lower than expected scores (mean difference = 9.5, 95% CI 7.7 to 11.3, P < .001). No unique patient characteristics were associated with high expectations (P > .05). CONCLUSIONS: To our knowledge, this study is the first to quantify preoperative patient expectations using the same metric as MCID to allow for direct comparison. Patient expectations for improvement following TKA are ∼2× greater than MCID and are significantly greater than predicted outcome scores. This discrepancy challenges currently accepted standards of success after TKA and indicates a need for improved expectation setting prior to surgery.

The role of intense athletic activity on structural lumbar abnormalities in adolescent patients with symptomatic low back pain.

PURPOSE: To determine if adolescent athletics increases the risk of structural abnormalities in the lumbar spine. METHODS: A retrospective review of patients (ages 10-18) between 2004 and 2012 was performed. Pediatric patients with symptomatic low back pain, a lumbar spine MRI, and reported weekly athletic activity were included. Patients were stratified to an "athlete" and "non-athlete" group. Lumbar magnetic resonance and plain radiographic imaging was randomized, blinded, and evaluated by two authors for a Pfirrmann grade, herniated disc, and/or pars fracture. RESULTS: A total of 114 patients met the inclusion criteria and were stratified into 66 athletes and 48 non-athletes. Athletes were more likely to have abnormal findings compared to non-athletes (67 vs. 40 %, respectively, p = 0.01). Specifically, the prevalence of a spondylolysis with or without a slip was higher in athletes vs. non-athletes (32 vs. 2 %, respectively, p = 0.0003); however, there was no difference in the average Pfirrmann grade (1.19 vs. 1.14, p = 0.41), percentage of patients with at least one degenerative disc (39 vs. 31 %, p = 0.41), or disc herniation (27 vs. 33 %, p = 0.43). Body mass index, smoking history, and pelvic incidence (51.5° vs. 48.7°, respectively, p = 0.41) were similar between the groups. CONCLUSION: Adolescents with low back pain have a higher-than-expected prevalence of structural pathology regardless of athletic activity. Independent of pelvic incidence, adolescent athletes with low back pain had a higher prevalence of spondylolysis compared to adolescent non-athletes with back pain, but there was no difference in associated disc degenerative changes or herniation.

What are the Risk Factors for Cerebrovascular Accidents After Elective Orthopaedic Surgery?

BACKGROUND: Perioperative cerebrovascular accidents (CVAs) are one of the leading causes of patient morbidity, mortality, and medical costs. However, little is known regarding the rates of these events and risk factors for CVA after elective orthopaedic surgery. QUESTIONS/PURPOSES: Our goals were to (1) establish the national, baseline proportion of patients experiencing a 30-day CVA and the timing of CVA; and (2) determine independent risk factors for 30-day CVA rates after common elective orthopaedic procedures. METHODS: Patients undergoing elective TKA, THA, posterior or posterolateral lumbar fusion, anterior cervical discectomy and fusion, and total shoulder arthroplasty, from 2006 to 2012, were identified from the American College of Surgeons National Surgical Quality Improvement Program(®) database. A total of 42,150 patients met inclusion criteria. Thirty-day CVA rates were recorded for each procedure, and patients were assessed for characteristics associated with CVA through univariate analysis. Multivariate regression models were created to identify independent risk factors for CVA. RESULTS: A total of 55 (0.13%) patients experienced a CVA within 30 days of the procedure, occurring a median of 2 days after surgery (range, 1-30 days) with 0.08% of patients experiencing a CVA after TKA, 0.15% after THA, 0.00% after single-level anterior cervical discectomy and fusion, 0.38% after multilevel anterior cervical discectomy and fusions, 0.20% after single-level posterior or posterolateral lumbar fusion, 0.70% after multilevel posterior or posterolateral lumbar fusion, and 0.22% after total shoulder arthroplasty. Independent risk factors for CVA included age of 75 years or older (odds ratio [OR], 2.50; 95% CI, 1.44-4.35; p = 0.001), insulin-dependent diabetes mellitus (OR, 3.08; CI, 1.47-6.45; p = 0.003), hypertension (OR, 2.71; CI, 1.19-6.13; p = 0.017), history of transient ischemic attack (OR, 2.83; CI, 1.24-6.45; p = 0.013), dyspnea (OR, 2.51; CI, 1.30-4.86; p = 0.006), chronic obstructive pulmonary disease (OR, 2.33; CI, 1.06-5.13; p = 0.036), and operative time of 180 minutes or greater (OR, 3.25; CI 1.60-6.60; p = 0.001). CONCLUSIONS: Numerous nonmodifiable patient comorbidities and increased operative time were associated with CVA after elective orthopaedic procedures. However, the American College of Surgeons National Surgical Quality Improvement Program(®) database does not code for cardiac arrhythmia or atrial fibrillation, which other studies have suggested may be important predictor variables; those may be important risk factors, although we were unable to evaluate them in our study. Surgeons should counsel patients with these risk factors and limit their operative time to reduce the risk of these adverse events, and future studies should examine other patient characteristics such as arrhythmia and noncoronary heart disease and assess the role of pharmacologic prophylaxis in patients with these risk factors. LEVEL OF EVIDENCE: Level III, prognostic study.

Cervical spine surgery in professional athletes: a systematic review.

Cervical surgery is one of the most common surgical spinal procedures performed around the world. The authors performed a systematic review of the literature reporting the outcomes of cervical spine surgery in high-level athletes in order to better understand the nuances of cervical spine pathology in this population. A search of the MEDLINE database using the search terms "cervical spine" AND "surgery" AND "athletes" yielded 54 abstracts. After exclusion of publications that did not meet the criteria for inclusion, a total of 8 papers reporting the outcome of cervical spine surgery in professional or elite athletes treated for symptoms secondary to cervical spine pathology (focusing in degenerative conditions) remained for analysis. Five of these involved the management of cervical disc herniation, 3 were specifically about traumatic neurapraxia. The majority of the patients included in this review were American football players. Anterior cervical discectomy and fusion (ACDF) was commonly performed in high-level athletes for the treatment of cervical disc herniation. Most of the studies suggested that return to play is safe for athletes who are asymptomatic after ACDF for cervical radiculopathy due to disc herniation. Surgical treatment may provide a higher rate of return to play for these athletes than nonsurgical treatment. Return to play after cervical spinal cord contusion may be possible in asymptomatic patients. Cervical cord signal changes on MRI may not be an absolute contraindication for return to play in neurologically intact patients, according to some authors. Cervical contusions secondary to cervical stenosis may be associated with a worse outcome and a higher recurrence rate than those those secondary to disc herniation. The evidence is low (Level IV) and individualized treatment must be recommended.

Surgical treatment of Type II odontoid fractures: anterior odontoid screw fixation or posterior cervical instrumented fusion?

Odontoid fractures comprise as many as 20% of all cervical spine fractures. Fractures at the dens base, classified by the Anderson and D'Alonzo system as Type II injuries, are the most common pattern of all odontoid fractures and are also the most common cervical injuries in patients older than 70 years of age. Surgical treatment is recommended for patients older than 50 years with Type II odontoid fractures, as well as in patients at a high risk for nonunion. Anterior odontoid screw fixation (AOSF) and posterior cervical instrumented fusion (PCIF) are both well-accepted techniques for surgical treatment but with unique indications and contraindications as well as varied reported outcomes. In this paper, the authors review the literature about specific patients and fracture characteristics that may guide treatment toward one technique over the other. AOSF can preserve atlantoaxial motion, but requires a reduced odontoid, an intact transverse ligament, and a favorable fracture line to achieve adequate fracture compression. Additionally, older patients may have a higher rate of pseudarthrosis using this technique, as well as postoperative dysphagia. PCIF has a higher rate of fusion and is indicated in patients with severe atlantoaxial misalignment and with poor bone quality. PCIF allows direct open reduction of displaced fragments and can reduce any atlantoaxial subluxation. It is also used as a salvage procedure after failed AOSF. However, this technique results in loss of atlantoaxial motion, requires prone positioning, and demands a longer operative duration than AOSF, factors that can be a challenge in patients with severe medical conditions. Although both anterior and posterior approaches are acceptable, many clinical and radiological factors should be taken into account when choosing the best surgical approach. Surgeons must be prepared to perform both procedures to adequately treat these injuries.

Surgical Site Infections in Spinal Surgery.

Surgical site infections (SSIs) are a potentially devastating complication of spine surgery. SSIs are defined by the Centers for Disease Control and Prevention as occurring within 30 days of surgery or within 12 months of placement of foreign bodies, such as spinal instrumentation. SSIs are commonly categorized by the depth of surgical tissue involvement (ie, superficial, deep incisional, or organ and surrounding space). Postoperative infections result in increased costs and postoperative morbidity. Because continued research has improved the evaluation and management of spinal infections, spine surgeons must be aware of these modalities. The controversies in evaluation and management of SSIs in spine surgery will be reviewed.

Vertebral Osteomyelitis and Spinal Epidural Abscess: An Evidence-based Review.

Spinal infections have historically been associated with significant morbidity and mortality. Current treatment protocols have improved patient outcomes through prompt and accurate infection identification, medical treatment, and surgical interventions. Medical and surgical management, however, remains controversial because of a paucity of high-level evidence to guide decision making. Despite this, an awareness of presenting symptoms, pertinent risk factors, and common imaging findings are critical for treating spine infections. The purpose of this article is to review the recent literature and present the latest evidence-based recommendations for the most commonly encountered primary spinal infections: vertebral osteomyelitis and epidural abscess.

The effect of aging on posterior intertransverse lumbar fusion: a New Zealand white rabbit model.

STUDY DESIGN: In vivo assessment of lumbar spinal fusion between a younger and older cohort of New Zealand white rabbits. OBJECTIVE: Directly compare fusion within young and aged New Zealand white rabbits to establish an aged spinal fusion model translational research. SUMMARY OF BACKGROUND DATA: Prior studies have utilized skeletally mature young rabbits (6-12 mo old) that may not be appropriate as an analog for studying the aging human spine. METHODS: Ten aged (>36 mo old) and 10 young (12 mo old) New Zealand white rabbits underwent a single-level, bilateral, L5-6 posterolateral intertransverse fusion using autogenous iliac crest bone graft. The animals were killed at 6 weeks postoperatively, and the specimens were then evaluated with quantitative microcomputerized tomography and manual palpation by 6 orthopedic surgeons. The fusions were graded as either fused or not fused by each examiner. The spines were then embedded in poly(methyl methacrylate) and cut into 2-mm-thick sections for histologic analysis. RESULTS: A higher percentage of young rabbits were determined to be successfully fused through manual palpation testing compared with the aged rabbits. Micro-computed tomography (CT) analysis revealed a significantly greater fusion mass volume in the younger rabbits than in the older cohort. In addition, the fusion density of the younger rabbits was found to be significantly lower than that of the older rabbits when normalized to the bone density in the nonfused portion of the spine. Histologic analysis showed that the quality of the bone within the fusion mass was consistent between the young and old rabbits. A greater number of young animals had bilateral continuous bone graft compared with the aged animals. CONCLUSIONS: The aged (>36 mo) New Zealand white rabbit model appears to be a valid model to evaluate the effect of aging on lumbar fusion and has the potential to more accurately model conditions that are present in the older human spine.

Measuring the impact of the Thoracolumbar Injury Classification and Severity Score among 458 consecutively treated patients.

CONTEXT: The Thoracolumbar Injury Classification and Severity Score (TLICS) was proposed to improve injury classification and guide surgical decision-making of thoracolumbar spinal trauma (TLST), but its impact on the care of patients has not been quantified. STUDY DESIGN: Retrospective study. PATIENT SAMPLE: Analysis of 458 patients treated for TLST trauma from 2000 through 2010 at a single center. Outcome measures Neurological status - ASIA Impairment Scale (AIS), failure of conservative treatment, and surgical complications. METHODS: Clinical and radiological data were evaluated. Patients were grouped according to the period before (2000-2006) and after (2007-2010) utilization of the TLICS. RESULTS: From 2000 to 2006, 148 patients were initially treated conservatively (C) and 66 were surgically (S) treated. In the C group, the TLICS ranged from 1 to 7 (median 1; mean 1.57). In the S group, the TLICS ranged from 2 to 10 (median 2; mean 4.14). The TLICS matched treatment in 97.9% of conservatively treated patients. From 2007 to 2010, 162 patients were initially treated C and 82 were treated S. In the C group, the TLICS ranged from 1 to 4 (median 1; mean 1.48). In the S group, the TLICS ranged from 2-10 (median 4; mean 4.4). The TLICS matched treatment in 98.8% of C-treated patients. Overall, failure of C treatment occurred in nine patients; most failures (7/9) and all three missed distractive injuries occurred prior to use of the TLICS. CONCLUSIONS: After introduction of the TLICS, there was a trend towards more successful conservative treatment with fewer conversions to surgical treatment.

Clinical results of patients with subaxial cervical spine trauma treated according to the SLIC score.

OBJECTIVE: The Subaxial Injury Classification (SLIC) system has been developed to improve injury classification and guide surgical decision making yet clinical validation remains necessary. METHODS: We evaluated the validity and safety of the SLIC system prospectively in patients treated for subaxial cervical spine trauma (SCST) between 2009 and 2012. Patients with four or more points were surgically treated, whereas patients with less than 4 points were conservatively managed. OUTCOME MEASURES: Neurological status was assessed as the primary outcome of successful treatment. RESULTS: Non-surgical group - Twenty-three patients were treated non-surgically, 14 (61%) of them with some follow-up at our institution. Follow-up ranged from 3 to 5 months (mean of 4.42; median 4). The SLIC score ranged from 0 to 6 points (mean and median of 1). One patient with a SLIC of 6 points refused surgery. Surgical group: Twenty-five patients were operated, but follow-up after hospital discharge was obtained in 23 (92%) patients (range from 1 to 24 months, mean of 5.82 months). The SLIC score in this group ranged from 4 to 9 points (mean and median of 7). No patients had neurological worsening. Eight of 13 patients with incomplete deficits had some improvement in American Spinal Injury Association score. CONCLUSIONS: This is the first prospective application of the SLIC system. With regard to our primary outcome, neurological status, the SLIC system was found to be a safe and effective guide in the surgical treatment of SCST.

Upper cervical injuries - a rational approach to guide surgical management.

CONTEXT: The complex anatomy and the importance of ligaments in providing stability at the upper cervical spine region (O-C1-C2) require the use of many imaging modalities to evaluate upper cervical injuries (UCI). While separate classifications have been developed for distinct injuries, a more practical treatment algorithm can be derived from the injury pattern in UCI. OBJECTIVE: To propose a practical treatment algorithm to guide treatment based on injuries characteristic of UCI. METHODS: A literature review was performed on the Pubmed database using the following keywords: (1) "occipital condyle injury"; (2) "craniocervical dislocation or atlanto-occipital dislocation or craniocervical dislocation"; (3) "atlas fractures"; and (4) "axis fractures". Just articles containing the diagnosis, classification, and treatment of specific UCI were included. The data obtained were analyzed by the authors, dividing the UCI into two groups: Group 1 - patients with clear ligamentous injury and Group 2 - patients with fractures without ligament disruption. RESULTS: Injuries with ligamentous disruption, suggesting surgical treatment, include: atlanto-occipital dislocation, mid-substance transverse ligament injury, and C1-2 and C2-3 ligamentous injuries. In contrast, condyle, atlas, and axis fractures without significant displacement/misalignment can be initially treated using external orthoses. Odontoid fractures with risk factors for non-union are an exception in Group 2 once they are better treated surgically. Patients with neurological deficits may have more unstable injuries. CONCLUSIONS: Ascertaining the status of relevant ligamentous structures, fracture patterns and alignment are important in determining surgical compared with non-surgical treatment for patients with UCI.

Preference Sensitive Care and Shared Decision-Making in Lumbar Spinal Stenosis: A Scoping Review.

STUDY DESIGN: Scoping review. OBJECTIVE: The objective of this study was to conduct a scoping review exploring the extent to which preference sensitivity has been studied in treatment decisions for lumbar spinal stenosis (LSS), utilizing shared decision-making (SDM) as a proxy. BACKGROUND: Preference-sensitive care involves situations where multiple treatment options exist with significant tradeoffs in cost, outcome, recovery time, and quality of life. LSS has gained research focus as a preference-sensitive care scenario. MATERIALS AND METHODS: A scoping review protocol in accordance with "Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews" regulations was registered with the Open Science Framework (ID: 9ewup) and conducted across multiple databases from January 2000 to October 2022. Study selection and characterization were performed by 3 independent reviewers and an unbiased moderator. RESULTS: The search resulted in the inclusion of 16 studies varying in design and sample size, with most published between 2016 and 2021. The studies examined variables related to SDM, patient preferences, surgeon preferences, and decision aids (DAs). The outcomes assessed included treatment choice, patient satisfaction, and patient understanding. Several studies reported that SDM influenced treatment choice and patient satisfaction, while the impact on patient understanding was less clear. DAs were used in some studies to facilitate SDM. CONCLUSION: The scoping review identified a gap in comprehensive studies analyzing the preference sensitivity of treatment for LSS and the role of DAs. Further research is needed to better understand the impact of patient preferences on treatment decisions and the effectiveness of DAs in LSS care. This review provides a foundation for future research in preference-sensitive care and SDM in the context of lumbar stenosis treatment.

Does Operative Level Impact Dysphagia Severity After Anterior Cervical Discectomy and Fusion?: A Multicenter Prospective Analysis.

STUDY DESIGN: Prospective multicenter cohort study. OBJECTIVE: To explore the association between operative level and postoperative dysphagia after anterior cervical discectomy and fusion (ACDF). BACKGROUND: Dysphagia is common after ACDF and has several risk factors, including soft tissue edema. The degree of prevertebral soft tissue edema varies based on the operative cervical level. However, the operative level has not been evaluated as a source of postoperative dysphagia. PATIENTS AND METHODS: Adult patients undergoing elective ACDF were prospectively enrolled at 3 academic centers. Dysphagia was assessed using the Bazaz Questionnaire, Dysphagia Short Questionnaire, and Eating Assessment Tool-10 (EAT-10) preoperatively and at 2, 6, 12, and 24 weeks postoperatively. Patients were grouped based on the inclusion of specific surgical levels in the fusion construct. Multivariable regression analyses were performed to evaluate the independent effects of the number of surgical levels and the inclusion of each particular level on dysphagia symptoms. RESULTS: A total of 130 patients were included. Overall, 24 (18.5%) patients had persistent postoperative dysphagia at 24 weeks and these patients were older, female, and less likely to drink alcohol. There was no difference in operative duration or dexamethasone administration. Patients with persistent dysphagia were significantly more likely to have C4-C5 included in the fusion construct (62.5% vs . 34.9%, P = 0.024) but there were no differences based on the inclusion of other levels. On multivariable regression, the inclusion of C3-C4 or C6-C7 was associated with more severe EAT-10 (ß: 9.56, P = 0.016 and ß: 8.15, P = 0.040) and Dysphagia Short Questionnaire (ß: 4.44, P = 0.023 and (ß: 4.27, P = 0.030) at 6 weeks. At 12 weeks, C3-C4 fusion was also independently associated with more severe dysphagia (EAT-10 ß: 4.74, P = 0.024). CONCLUSION: The location of prevertebral soft tissue swelling may impact the duration and severity of patient-reported dysphagia outcomes at up to 24 weeks postoperatively. In particular, the inclusion of C3-C4 and C4-C5 into the fusion may be associated with dysphagia severity.

A Novel Method for Tracking Neck Motions Using a Skin-Conformable Wireless Accelerometer: A Pilot Study.

Introduction: Cervical spine disease is a leading cause of pain and disability. Degenerative conditions of the spine can result in neurologic compression of the cervical spinal cord or nerve roots and may be surgically treated with an anterior cervical discectomy and fusion (ACDF) in up to 137,000 people per year in the United States. A common sequelae of ACDF is reduced cervical range of motion (CROM) with patient-based complaints of stiffness and neck pain. Currently, tools for assessment of CROM are manual, subjective, and only intermittently utilized during doctor or physical therapy visits. We propose a skin-mountable acousto-mechanic sensor (ADvanced Acousto-Mechanic sensor; ADAM) as a tool for continuous neck motion monitoring in postoperative ACDF patients. We have developed and validated a machine learning neck motion classification algorithm to differentiate between eight neck motions (right/left rotation, right/left lateral bending, flexion, extension, retraction, protraction) in healthy normal subjects and patients. Methods: Sensor data from 12 healthy normal subjects and 5 patients were used to develop and validate a Convolutional Neural Network (CNN). Results: An average algorithm accuracy of 80.0 ± 3.8% was obtained for healthy normal subjects (94% for right rotation, 98% for left rotation, 65% for right lateral bending, 87% for left lateral bending, 89% for flexion, 77% for extension, 50% for retraction, 84% for protraction). An average accuracy of 67.5 ± 5.8% was obtained for patients. Discussion: ADAM, with our algorithm, may serve as a rehabilitation tool for neck motion monitoring in postoperative ACDF patients. Sensor-captured vital signs and other events (extubation, vocalization, physical therapy, walking) are potential metrics to be incorporated into our algorithm to offer more holistic monitoring of patients after cervical spine surgery.

The precision, accuracy and validity of detecting posterior ligamentous complex injuries of the thoracic and lumbar spine: a critical appraisal of the literature.

PURPOSE: The diagnostic assessment and prognostic value of the posterior ligamentous complex (PLC) remains a controversial topic in the management of patients with thoracolumbar spinal injury. The purpose of this review was to critically appraise the literature and present an overview of the: (1) precision, (2) accuracy, and (3) validity of detecting PLC injuries in patients with thoracic and lumbar spine trauma. METHODS: Studies evaluating the precision, accuracy and/or validity of detecting and managing PLC injuries in patients with thoracic and/or lumbar spine injuries were searched through the Medline database (1966 to September 2011). References were retrieved and evaluated individually and independently by two authors. RESULTS: Twenty-one eligible studies were identified. Few studies reported the use of countermeasures for sampling and measurement bias. In nine agreement studies, the PLC was assessed in various ways, ranging from use of booklets to a complete set of diagnostic imaging. Inter-rater and intra-rater kappa values ranged from 0.188 to 0.915 and 0.455 to 0.840, respectively. In nine accuracy studies, magnetic resonance (MR) imaging was most often (n = 6) compared with intra-operative findings. In general, MR imaging tended to demonstrate relatively high negative predictive values and relatively low positive predictive values for PLC injuries. CONCLUSIONS: A wide variety of methods have been applied in the evaluation of precision and accuracy of PLC injury detection, leaving spinal surgeons with a multitude of variable results. There is scant clinical evidence demonstrating the true prognostic value of detected PLC injuries in patients with thoracic and lumbar spine injuries. We recommend the conduct of longitudinal clinical follow-up studies on those cases assessed for precision and/or accuracy of PLC injuries.

Biomechanical evaluation of a low profile, anchored cervical interbody spacer device in the setting of progressive flexion-distraction injury of the cervical spine.

INTRODUCTION: Anterior cervical decompression and fusion is a well-established procedure for treatment of degenerative disc disease and cervical trauma including flexion-distraction injuries. Low-profile interbody devices incorporating fixation have been introduced to avoid potential issues associated with dissection and traditional instrumentation. While these devices have been assessed in traditional models, they have not been evaluated in the setting of traumatic spine injury. This study investigated the ability of these devices to stabilize the subaxial cervical spine in the presence of flexion-distraction injuries of increasing severity. METHODS: Thirteen human cadaveric subaxial cervical spines (C3-C7) were tested at C5-C6 in flexion-extension, lateral bending and axial rotation in the load-control mode under ±1.5 Nm moments. Six spines were tested with locked screw configuration and seven with variable angle screw configuration. After testing the range of motion (ROM) with implanted device, progressive posterior destabilization was performed in 3 stages at C5-C6. RESULTS: The anchored spacer device with locked screw configuration significantly reduced C5-C6 flexion-extension (FE) motion from 14.8 ± 4.2 to 3.9 ± 1.8°, lateral bending (LB) from 10.3 ± 2.0 to 1.6 ± 0.8, and axial rotation (AR) from 11.0 ± 2.4 to 2.5 ± 0.8 compared with intact under (p < 0.01). The anchored spacer device with variable angle screw configuration also significantly reduced C5-C6 FE motion from 10.7 ± 1.7 to 5.5 ± 2.5°, LB from 8.3 ± 1.4 to 2.7 ± 1.0, and AR from 8.8 ± 2.7 to 4.6 ± 1.3 compared with intact (p < 0.01). The ROM of the C5-C6 segment with locked screw configuration and grade-3 F-D injury was significantly reduced from intact, with residual motions of 5.1 ± 2.1 in FE, 2.0 ± 1.1 in LB, and 3.3 ± 1.4 in AR. Conversely, the ROM of the C5-C6 segment with variable-angle screw configuration and grade-3 F-D injury was not significantly reduced from intact, with residual motions of 8.7 ± 4.5 in FE, 5.0 ± 1.6 in LB, and 9.5 ± 4.6 in AR. CONCLUSIONS: The locked screw spacer showed significantly reduced motion compared with the intact spine even in the setting of progressive flexion-distraction injury. The variable angle screw spacer did not sufficiently stabilize flexion-distraction injuries. The resulting motion for both constructs was higher than that reported in previous studies using traditional plating. Locked screw spacers may be utilized with additional external immobilization while variable angle screw spacers should not be used in patients with flexion-distraction injuries.

Lumbar spinal stenosis.

Lumbar spinal stenosis affects many patients and is one of the most common reasons for spinal surgery in the elderly population. New research and surgical innovations have resulted in a better understanding of the disease and its diagnosis and treatment. To select the optimal treatment approach for each patient, it is helpful to review patient presentations, diagnostic workups, surgical and nonsurgical treatment options, evidence-based outcomes, and the pathophysiology of lumbar spinal stenosis.

Relationships between the Arbeitsgemeinschaft für Osteosynthesefragen Spine System and the Thoracolumbar Injury Classification System: an analysis of the literature.

CONTEXT: The Thoracolumbar Injury Classification System (TLICS) has been recently described to help surgeons in the decision-making process of thoracolumbar spinal trauma. OBJECTIVE: To analyze the potential relationships between the TLICS scores with the Arbeitsgemeinschaft für Osteosynthesefragen (AO) Spine System and patient's neurological status. METHODS: Literature analysis of the potential scored injuries in the TLICS system, based on its individual scores, its total score, and its suggested proposed treatment, correlating these with the AO system and neurological status. RESULTS: Findings are presented according to the TLICS score. Patients with a TLICS 1-3 points, receiving conservative treatment, are AO type A injuries, generally neurologically intact. TLICS 4 group also included AO type A fractures, neurologically ranging from intact to complete spinal cord injury. TLICS 5-10 points includes AO type B and C injuries, regarding their neurological status, and burst fractures (AO type A) with concomitant neurological injury and most of the patients with incomplete deficits and cauda equina syndrome. CONCLUSIONS: As a general overview, according to the TLICS, patients without neurological deficit and with AO type A injuries are conservatively treated. AO type B and C injuries are managed surgically, with regard to neurological status. Patients with cauda equina or incomplete injuries also received a higher severity score. Controversies still exist regarding the management of unstable burst fractures without neurological status. The role of the posterior ligamentous complex status and the magnetic resonance imaging in the decision-making process require more clinical evidence.

Spine Surgery and Ankylosing Spondylitis: Optimizing Perioperative Management.

Ankylosing spondylitis (AS) is a common form of axial spondyloarthritis, characterized by inflammatory back pain, radiographic sacroiliitis, excess spinal bone formation, and a high prevalence of HLA-B27. Commonly, AS patients require spinal surgery for kyphotic deformities, spinal trauma, and spinal infections. For preoperative management, proper interruption considering each specific half-lives of disease-modifying antirheumatic drugs are necessary to avoid complications, such as infections. When feasible, bone quality assessment before surgery is mandatory. For intraoperative measurements, airway management should be carefully evaluated, especially in patients with severe cervical deformities. Cardiac, renal, and pulmonary assessment should be made considering specific pathologic characteristics involved in AS patients, such as pulmonary restrictive disease and chronic anti-inflammatory drugs use. Multimodal neurophysiological intraoperative monitoring is recommended once these patients had a high risk for neurological deterioration. At the postoperative period, early oral intake, early mobilization, and aggressive pain control may decrease complications and enhance recovery. AS presents several unique challenges that require specific attention around spine surgery. This includes handling preoperative and postoperative pharmacotherapeutics, intraoperative airway management, and the mitigation of postoperative complications. In this paper, we provide a literature review of optimal strategies for the perioperative management for patients with AS.

AOA Critical Issues Symposium: Shaping the Impact of Artificial Intelligence within Orthopaedic Surgery.

ABSTRACT: Artificial intelligence (AI) is a broad term that is widely used but inconsistently understood. It refers to the ability of any machine to exhibit human-like intelligence by making decisions, solving problems, or learning from experience. With its ability to rapidly process large amounts of information, AI has already transformed many industries such as entertainment, transportation, and communications through consumer-facing products and business-to-business applications. Given its potential, AI is also anticipated to impact the practice of medicine and the delivery of health care. Interest in AI-based techniques has grown rapidly within the orthopaedic community, resulting in an increasing number of publications on this topic. Topics of interest have ranged from the use of AI for imaging interpretation to AI-based techniques for predicting postoperative outcomes.The highly technical and data-driven nature of orthopaedic surgery creates the potential for AI, and its subdisciplines machine learning (ML) and deep learning (DL), to fundamentally transform our understanding of musculoskeletal care. However, AI-based techniques are not well known to most orthopaedic surgeons, nor are they taught with the same level of insight and critical thinking as traditional statistical methodology. With a clear understanding of the science behind AI-based techniques, orthopaedic surgeons will be able to identify the potential pitfalls of the application of AI to musculoskeletal health. Additionally, with increased understanding of AI, surgeons and their patients may have more trust in the results of AI-based analytics, thereby expanding the potential use of AI in clinical care and amplifying the impact it could have in improving quality and value. The purpose of this American Orthopaedic Association (AOA) symposium was to facilitate understanding and development of AI and AI-based techniques within orthopaedic surgery by defining common terminology related to AI, demonstrating the existing clinical utility of AI, and presenting future applications of AI in surgical care.