Do Hounsfield Units From Intraoperative CT Scans Correlate With Preoperative Values?

BACKGROUND

There is increasing interest in forecasting postoperative complications using bone density metrics. Vertebral Hounsfield unit measurements obtained from CT scans performed for surgical planning or other purposes, known as opportunistic CTs, have shown promise for their ease of measurement and the ability to target density measurement to a particular region of interest. Concomitant with the rising interest in prognostic bone density measurement use has been the increasing adoption of intraoperative advanced imaging techniques. Despite the interest in both outcome prognostication and intraoperative advanced imaging, there is little information regarding the use of CT-based intraoperative imaging as a means to measure bone density.

QUESTIONS/PURPOSES

(1) Can vertebral Hounsfield units be reliably measured by physician reviewers from CT scans obtained intraoperatively? (2) Do Hounsfield units measured from intraoperative studies correlate with values measured from preoperative CT scans?

METHODS

To be eligible for this retrospective study, patients had to have been treated with the use of an intraoperative CT scan for instrumented spinal fusion for either degenerative conditions or traumatic injuries between January 2015 and December 2022. Importantly, patients without a preoperative CT scan of the fused levels within 180 days before surgery or who were indicated for surgery because of infection, metastatic disease, or who were having revision surgery after prior instrumentation were excluded from the query. Of the 285 patients meeting these inclusion criteria, 53% (151) were initially excluded for the following reasons: 36% (102) had intraoperative CT scans obtained after placement of instrumentation, 16% (47) had undergone intraoperative CT scans but the studies were not accessible for Hounsfield unit measurement, and 0.7% (2) had prior kyphoplasty wherein the cement prevented Hounsfield unit measurement. Finally, an additional 19% (53) of patients were excluded because the preoperative CT and intraoperative CT were obtained at different peak voltages, which can influence Hounsfield unit measurement. This yielded a final population of 81 patients from whom 276 preoperative and 276 intraoperative vertebral Hounsfield unit measurements were taken. Hounsfield unit data were abstracted from the same vertebra(e) from both preoperative and intraoperative studies by two physician reviewers (one PGY3 and one PGY5 orthopaedic surgery resident, both pursuing spine surgery fellowships). For a small, representative subset of patients, measurements were taken by both reviewers. The feasibility and reliability of Hounsfield unit measurement were then assessed with interrater reliability of values measured from the same vertebra by the two different reviewers. To compare Hounsfield unit values from intraoperative CT scans with preoperative CT studies, an intraclass correlation using a two-way random effects, absolute agreement testing technique was employed. Because the data were formatted as multiple measurements from the same vertebra at different times, a repeated measures correlation was used to assess the relationship between preoperative and intraoperative Hounsfield unit values. Finally, a linear mixed model with patients handled as a random effect was used to control for different patient and clinical factors (age, BMI, use of bone density modifying agents, American Society of Anesthesiologists [ASA] classification, smoking status, and total Charlson comorbidity index [CCI] score).

RESULTS

We found that Hounsfield units can be reliably measured from intraoperative CT scans by human raters with good concordance. Hounsfield unit measurements of 31 vertebrae from a representative sample of 10 patients, measured by both reviewers, demonstrated a correlation value of 0.82 (95% CI 0.66 to 0.91), indicating good correlation. With regard to the relationship between preoperative and intraoperative measurements of the same vertebra, repeated measures correlation testing demonstrated no correlation between preoperative and intraoperative measurements (r = 0.01 [95% CI -0.13 to 0.15]; p = 0.84). When controlling for patient and clinical factors, we continued to observe no relationship between preoperative and intraoperative Hounsfield unit measurements.

CONCLUSION

As intraoperative CT and measurement of vertebral Hounsfield units both become increasingly popular, it would be a natural extension for spine surgeons to try to extract Hounsfield unit data from intraoperative CTs. However, we found that although it is feasible to measure Hounsfield data from intraoperative CT scans, the obtained values do not have any predictable relationship with values obtained from preoperative studies, and thus, these values should not be used interchangeably. With this knowledge, future studies should explore the prognostic value of intraoperative Hounsfield unit measurements as a distinct entity from preoperative measurements.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Primary Care Physician Preferences Regarding Communication from Orthopaedic Surgeons

BACKGROUND

Musculoskeletal consultations constitute a growing portion of primary care physician (PCP) referrals. Optimizing communication between PCPs and orthopaedists can potentially reduce time spent in the electronic medical record (EMR) as well as physician burnout. Little is known about the preferences of PCPs regarding communication from orthopaedic surgeons. Hence, the present study investigated, across a large health network, the preferences of PCPs regarding communication from orthopaedists.

METHODS

A total of 175 PCPs across 15 practices within our health network were surveyed. These providers universally utilized Epic as their EMR platform. Five-point, labeled Likert scales were utilized to assess the PCP-perceived importance of communication from orthopaedists in specific clinical scenarios. PCPs were further asked to report their preferred method of communication in each scenario and their overall interest in communication from orthopaedists. Logistic regression analyses were performed to determine whether any PCP characteristics were associated with the preferred method of communication and the overall PCP interest in communication from orthopaedists.

RESULTS

A total of 107 PCPs (61.1%) responded to the survey. PCPs most commonly rated communication from orthopaedists as highly important in the scenario of an orthopaedist needing information from the PCP. In this scenario, PCPs preferred to receive an Epic Staff Message. Scenarios involving a recommendation for surgery, hospitalization, or a major clinical change were also rated as highly important. In these scenarios, an Epic CC'd Chart rather than a Staff Message was preferred. Increased after-hours EMR use was associated with diminished odds of having a high interest in communication from orthopaedists (odds ratio, 0.65; 95% confidence interval, 0.48 to 0.88; p = 0.005). Ninety-three PCPs (86.9%) reported spending 1 to 1.5 hours or more per day in Epic after normal clinical hours, and 27 (25.2%) spent >3 hours per day. Forty-six PCPs (43.0%) reported experiencing ≥1 symptom of burnout.

CONCLUSIONS

There were distinct preferences among PCPs regarding clinical communication from orthopaedic surgeons. There was also evidence of substantial burnout and after-hours work effort by PCPs. These results may help to optimize communication between PCPs and orthopaedists while reducing the amount of time that PCPs spend in the EMR.

The utility of vertebral Hounsfield units as a prognostic indicator of adverse events following treatment of spinal epidural abscess

Background

Spinal epidural abscesses (SEAs) are a devastating condition with high levels of associated morbidity and mortality. Hounsfield units (HUs), a marker of radiodensity on CT scans, have previously been correlated with adverse events following spinal interventions. We evaluated whether HUs might also be associated with all-cause complications and/or mortality in this high-risk population.

Methods

This retrospective cohort study was carried out within an academic health system in the United States. Adults diagnosed with a SEA between 2006 and 2021 and who also had a CT scan characterizing their SEA within 6 months of diagnosis were considered. HUs were abstracted from the 4 vertebral bodies nearest to, but not including, the infected levels. Our primary outcome was the presence of composite 90-day complications and HUs represented the primary predictor. A multivariable logistic regression analysis was conducted adjusting for demographic and disease-specific confounders. In sensitivity testing, separate logistic regression analyses were conducted (1) in patients aged 65 and older and (2) with mortality as the primary outcome.

Results

Our cohort consisted of 399 patients. The overall incidence of 90-day complications was 61.2% (n=244), with a 7.8% (n=31) 90-day mortality rate. Those experiencing complications were more likely to have undergone surgery to treat their SEA (58.6% vs. 46.5%; p=.018) but otherwise the cohorts were similar. HUs were not associated with composite 90-day complications (Odds ratio [OR] 1.00 [95% CI 1.00-1.00]; p=.842). Similar findings were noted in sensitivity testing.

Conclusions

While HUs have previously been correlated with adverse events in certain clinical contexts, we found no evidence to suggest that HUs are associated with all-cause complications or mortality in patients with SEAs. Future research hoping to leverage 3-dimensional imaging as a prognostic measure in this patient population should focus on alternative targets.

Level of Evidence

Level III; Observational Cohort study.

Intraoperative navigation increases the projected lifetime cancer risk in patients undergoing surgery for adolescent idiopathic scoliosis

BACKGROUND CONTEXT

Adolescent idiopathic scoliosis (AIS) is a common condition, often requiring surgical correction. Computed tomography (CT) based navigation technologies, which rely on ionizing radiation, are increasingly being utilized for surgical treatment. Although this population is highly vulnerable to radiation, given their age and female predominance, there is little available information elucidating modeled iatrogenic cancer risk.

PURPOSE

To model lifetime cancer risk associated with the use of intraoperative CT-based navigation for surgical treatment of AIS.

STUDY DESIGN/SETTING

This retrospective cross-sectional study took place in a quaternary care academic pediatric hospital in the United States.

PATIENT SAMPLE

Adolescents aged 10-18 who underwent posterior spinal fusion for a diagnosis of AIS between July 2014 and December 2019.

OUTCOMES MEASURES

Effective radiation dose and projected lifetime cancer risk associated with intraoperative doses of ionizing radiation.

METHODS

Clinical and radiographic parameters were abstracted, including total radiation dose during surgery from flat plate radiographs, fluoroscopy, and intraoperative CT scans. Multivariable regression analysis was used to assess differences in radiation exposure between patients treated with conventional radiography versus intraoperative navigation. Radiation exposure was translated into lifetime cancer risk using well-established algorithms.

RESULTS

In total, 245 patients were included, 119 of whom were treated with navigation. The cohort was 82.9% female and 14.4 years of age. The median radiation exposure (in millisieverts, mSv) for fluoroscopy, radiography, and navigation was 0.05, 4.14, and 8.19 mSv, respectively. When accounting for clinical and radiographic differences, patients treated with intraoperative navigation received 8.18 mSv more radiation (95%CI: 7.22-9.15, p<.001). This increase in radiation projects to 0.90 iatrogenic malignancies per 1,000 patients (95%CI 0.79-1.01).

CONCLUSIONS

Ours is the first work to define cancer risk in the setting of radiation exposure for navigated AIS surgery. We project that intraoperative navigation will generate approximately one iatrogenic malignancy for every 1,000 patients treated. Given that spine surgery for AIS is common and occurs in the context of a multitude of other radiation sources, these data highlight the need for radiation budgeting protocols and continued development of lower radiation dose technologies.

LEVEL OF EVIDENCE

Therapeutic, III.

The Use of the Lateral Tibial Line to Assess Ankle Alignment: A Preliminary Investigation

BACKGROUND

Although the medial clear space (MCS) is commonly used to assess talar alignment and ankle stability, its measurement is variable with multiple reported normal values. We have observed that the lateral tibial shaft is a reliable landmark to assess talar alignment. The objective of the current investigation was to determine the normal relationship of the lateral tibia to the superolateral talus using a tangent drawn inferiorly from the lateral tibial shaft, which we refer to as the "lateral tibial line" (LTL).

METHODS

The relationship of the LTL to the superolateral talus was assessed by three reviewers on 99 standing ankle mortise radiographs in uninjured patients. This relationship was quantified by measuring the distance (in millimeters) between the LTL and the superolateral talus. In addition, the interobserver reliability of the LTL measurement was recorded and compared with that of the MCS.

RESULTS

The median value for the distance between the superolateral talus and LTL was -0.50 mm with an interquartile range of -1.4 to 0.0 mm. The LTL was within 1 mm of the lateral talus in 176 of 297 reviewer measurements (59.3%). Moreover, it was either lateral to or at most 1 mm medial to the lateral talus in 90.9% of cases. The LTL measurement also demonstrated good interobserver reliability (0.764, 95% confidence interval, 0.670 to 0.834), similar to the measurement of MCS (0.742, 95% confidence interval, 0.539 to 0.846).

CONCLUSIONS

The relationship between the LTL and superolateral talus is easily measured with good reliability for assessing the anatomic relationship of the tibia and talus. The LTL uncommonly fell more than 1 mm medial to the superolateral talus, as might be seen with displaced ankle fractures. These findings will hopefully serve as a basis for future studies evaluating its role in assessing lateral displacement and stability of isolated fibula fractures.

LEVEL OF EVIDENCE

Level III, retrospective review.

Does the Stopping Opioids After Surgery Score Perform Well Among Racial and Socioeconomic Subgroups?

BACKGROUND

The Stopping Opioids After Surgery (SOS) score is a validated tool that was developed to determine the risk of sustained opioid use after surgical interventions, including orthopaedic procedures. Despite prior investigations validating the SOS score in diverse contexts, its performance across racial, ethnic, and socioeconomic subgroups has not been assessed.

QUESTIONS/PURPOSES

In a large, urban, academic health network, did the performance of the SOS score differ depending on (1) race and ethnicity or (2) socioeconomic status?

METHODS

This retrospective investigation was conducted using data from an internal, longitudinally maintained registry of a large, urban, academic health system in the Northeastern United States. Between January 1, 2018, and March 31, 2022, we treated 26,732 adult patients via rotator cuff repair, lumbar discectomy, lumbar fusion, TKA, THA, ankle or distal radius open reduction and internal fixation, or ACL reconstruction. We excluded 1% of patients (274 of 26,732) because of missing length of stay information, 0.06% (15) for missing discharge information, 1% (310) for missing medication information related to loss to follow-up, and 0.07% (19) who died during their hospital stay. Based on these inclusion and exclusion criteria, 26,114 adult patients were left for analysis. The median age in our cohort was 63 years (IQR 52 to 71), and most patients were women (52% [13,462 of 26,114]). Most patients self-reported their race and ethnicity as non-Hispanic White (78% [20,408 of 26,114]), but the cohort also included non-Hispanic Black (4% [939]), non-Hispanic Asian (2% [638]), and Hispanic (1% [365]) patients. Five percent (1295) of patients were of low socioeconomic status, defined by prior SOS score investigations as patients with Medicaid insurance. Components of the SOS score and the observed frequency of sustained postoperative opioid prescriptions were abstracted. The performance of the SOS score was compared across racial, ethnic, and socioeconomic subgroups using the c-statistic, which measures the capacity of the model to differentiate between patients with and without sustained opioid use. This measure should be interpreted on a scale between 0 and 1, where 0 represents a model that perfectly predicts the wrong classification, 0.5 represents performance no better than chance, and 1.0 represents perfect discrimination. Scores less than 0.7 are generally considered poor. The baseline performance of the SOS score in past investigations has ranged from 0.76 to 0.80.

RESULTS

The c-statistic for non-Hispanic White patients was 0.79 (95% CI 0.78 to 0.81), which fell within the range of past investigations. The SOS score performed worse for Hispanic patients (c-statistic 0.66 [95% CI 0.52 to 0.79]; p < 0.001), where it tended to overestimate patients' risks of sustained opioid use. The SOS score for non-Hispanic Asian patients did not perform worse than in the White patient population (c-statistic 0.79 [95% CI 0.67 to 0.90]; p = 0.65). Similarly, the degree of overlapping CIs suggests that the SOS score did not perform worse in the non-Hispanic Black population (c-statistic 0.75 [95% CI 0.69 to 0.81]; p = 0.003). There was no difference in score performance among socioeconomic groups (c-statistic 0.79 [95% CI 0.74 to 0.83] for socioeconomically disadvantaged patients; 0.78 [95% CI 0.77 to 0.80] for patients who were not socioeconomically disadvantaged; p = 0.92).

CONCLUSION

The SOS score performed adequately for non-Hispanic White patients but performed worse for Hispanic patients, where the 95% CI nearly included an area under the curve value of 0.5, suggesting that the tool is no better than chance at predicting sustained opioid use for Hispanic patients. In the Hispanic population, it commonly overestimated the risk of opioid dependence. Its performance did not differ among patients of different sociodemographic backgrounds. Future studies might seek to contextualize why the SOS score overestimates expected opioid prescriptions for Hispanic patients and how the utility performs among more specific Hispanic subgroups.

CLINICAL RELEVANCE

The SOS score is a valuable tool in ongoing efforts to combat the opioid epidemic; however, disparities exist in terms of its clinical applicability. Based on this analysis, the SOS score should not be used for Hispanic patients. Additionally, we provide a framework for how other predictive models should be tested in various lesser-represented populations before implementation.

Validation of the Stopping Opioids After Surgery (SOS) Score for the Sustained Use of Prescription Opioids Following Orthopaedic Surgery

BACKGROUND

The Stopping Opioids after Surgery (SOS) score was developed to identify patients at risk for sustained opioid use following surgery. The SOS score has not been specifically validated for patients in a general orthopaedic context. Our primary objective was to validate the SOS score within this context.

METHODS

In this retrospective cohort study, we considered a broad array of representative orthopaedic procedures performed between January 1, 2018, and March 31, 2022. These procedures included rotator cuff repair, lumbar discectomy, lumbar fusion, total knee and total hip arthroplasty, open reduction and internal fixation (ORIF) of ankle fracture, ORIF of distal radial fracture, and anterior cruciate ligament reconstruction. The performance of the SOS score was evaluated by calculating the c-statistic, receiver operating characteristic curve, and the observed rates of sustained prescription opioid use (defined as uninterrupted prescriptions of opioids for ≥90 days) following surgery. For our sensitivity analysis, we compared these metrics among various time epochs related to the COVID-19 pandemic.

RESULTS

A total of 26,114 patients were included, of whom 51.6% were female and 78.1% were White. The median age was 63 years. The observed prevalence of sustained opioid use was 1.3% (95% confidence interval [CI], 1.2% to 1.5%) in the low-risk group (SOS score of <30), 7.4% (95% CI, 6.9% to 8.0%) in the medium-risk group (SOS score of 30 to 60), and 20.8% (95% CI, 17.7% to 24.2%) in the high-risk group (SOS score of >60). The performance of the SOS score in the overall group was strong, with a c-statistic of 0.82. The performance of the SOS score showed no evidence of worsening over time. The c-statistic was 0.79 before the COVID-19 pandemic and ranged from 0.77 to 0.80 throughout the waves of the pandemic.

CONCLUSIONS

We validated the use of the SOS score for sustained prescription opioid use following a diverse array of orthopaedic procedures across subspecialties. This tool is easy to implement for the purpose of prospectively identifying patients in musculoskeletal service lines who are at higher risk for sustained opioid use, thereby enabling the future implementation of upstream interventions and modifications to avert opioid abuse and to combat the opioid epidemic.

LEVEL OF EVIDENCE

Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Neurologic Outcomes After Radiation Therapy for Severe Spinal Cord Compression in Multiple Myeloma: A Study of 162 Patients

BACKGROUND

Bone destruction is the most frequent disease-defining clinical feature of multiple myeloma (MM), resulting in skeletal-related events such as back pain, pathological fractures, or neurologic compromise including epidural spinal cord compression (ESCC). Up to 24% of patients with MM will be affected by ESCC. Radiation therapy has been proven to be highly effective in pain relief in patients with MM. However, a critical knowledge gap remains with regard to neurologic outcomes in patients with high-grade ESCC treated with radiation.

METHODS

We retrospectively included 162 patients with MM and high-grade ESCC (grade 2 or 3) who underwent radiation therapy of the spine between January 2010 and July 2021. The primary outcome was the American Spinal Injury Association (ASIA) score after 12 to 24 months, or the last known ASIA score if the patient had had a repeat treatment or died. Multivariable logistic regression was used to assess factors associated with poor neurologic outcomes after radiation, defined as neurologic deterioration or lack of improvement.

RESULTS

After radiation therapy, 34 patients (21%) had no improvement in their impaired neurologic function and 27 (17%) deteriorated neurologically. Thirty-six patients (22%) underwent either surgery or repeat irradiation after the initial radiation therapy. There were 100 patients who were neurologically intact at baseline (ASIA score of E), of whom 16 (16%) had neurologic deterioration. Four variables were independently associated with poor neurologic outcomes: baseline ASIA (odds ratio [OR] = 6.50; 95% confidence interval [CI] = 2.70 to 17.38; p < 0.001), Eastern Cooperative Oncology Group (ECOG) performance status (OR = 6.19; 95% CI = 1.49 to 29.49; p = 0.015), number of levels affected by ESCC (OR = 4.02; 95% CI = 1.19 to 14.18; p = 0.026), and receiving steroids prior to radiation (OR = 4.42; 95% CI = 1.41 to 16.10; p = 0.015).

CONCLUSIONS

Our study showed that 38% of patients deteriorated or did not improve neurologically after radiation therapy for high-grade ESCC. The results highlight the need for multidisciplinary input and efforts in the treatment of high-grade ESCC in patients with MM. Future studies will help to improve patient selection for specific and standardized treatments and to clearly delineate which patients are likely to benefit from radiation therapy.

LEVEL OF EVIDENCE

Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Neurological Outcomes and the Need for Retreatments Among Multiple Myeloma Patients With High-Grade Spinal Cord Compression: Radiotherapy vs Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Up to 30% of Multiple Myeloma (MM) patients are expected to experience Epidural Spinal Cord Compression (ESCC) during the course of their disease. To prevent irreversible neurological damage, timely diagnosis and treatment are important. However, debate remains regarding the optimal treatment regimen. The aim of this study was to investigate the neurological outcomes and frequency of retreatments for MM patients undergoing isolated radiotherapy and surgical interventions for high-grade (grade 2-3) ESCC.

METHODS

This study included patients with MM and high-grade ESCC treated with isolated radiotherapy or surgery. Pre- and post-treatment American Spinal Injury Association (ASIA) impairment scale and retreatment rate were compared between the 2 groups. Adjusted multivariable logistic regression was utilized to examine differences in neurologic compromise, pain, and retreatments.

RESULTS

A total of 247 patients were included (Radiotherapy: n = 154; Surgery: n = 93). After radiotherapy, 82 patients (53%) achieved full neurologic function (ASIA E) at the end of follow-up. Of the surgically treated patients, 67 (64%) achieved full neurologic function. In adjusted analyses, patients treated with surgery were less likely to experience neurologic deterioration within 2 years (OR = .15; 95%CI .05-.44; P = .001) and had less pain (OR = .29; 95%CI .11-.74; P = .010). Surgical treatment was not associated with an increased risk of retreatments (OR = .64; 95%CI .28-1.47; P = .29) or death (HR = .62, 95%CI .28-1.38; P = .24).

CONCLUSIONS

After adjusting for baseline differences, surgically treated patients with high-grade ESCC showed better neurologic outcomes compared to patients treated with radiotherapy. There were no differences in risk of retreatment or death.

Projected Lifetime Cancer Risk Associated With Intraoperative Computed Tomography for Lumbar Spine Surgery

STUDY DESIGN

Retrospective cross-sectional study.

OBJECTIVE

(1) To determine the incremental increase in intraoperative ionizing radiation conferred by computed tomography (CT) as compared with conventional radiography; and (2) to model different lifetime cancer risks contextualized by the intersection between age, sex, and intraoperative imaging modality.

SUMMARY OF BACKGROUND DATA

Emerging technologies in spine surgery, like navigation, automation, and augmented reality, commonly utilize intraoperative CT. Although much has been written about the benefits of such imaging modalities, the inherent risk profile of increasing intraoperative CT has not been well evaluated.

MATERIALS AND METHODS

Effective doses of intraoperative ionizing radiation were extracted from 610 adult patients who underwent single-level instrumented fusion for lumbar degenerative or isthmic spondylolisthesis from January 2015 through January 2022. Patients were divided into those who received intraoperative CT (n=138) and those who underwent conventional intraoperative radiography (n=472). Generalized linear modeling was utilized with intraoperative CT use as a primary predictor and patient demographics, disease characteristics, and preference-sensitive intraoperative considerations ( e.g. surgical approach and surgical invasiveness) as covariates. The adjusted risk difference in radiation dose calculated from our regression analysis was used to prognosticate the associated cancer risk across age and sex strata.

RESULTS

(1) After adjusting for covariates, intraoperative CT was associated with 7.6 mSv (interquartile range: 6.8-8.4 mSv; P <0.001) more radiation than conventional radiography. (2) For the median patient in our population (a 62-year-old female), intraoperative CT use increased lifetime cancer risk by 2.3 incidents (interquartile range: 2.1-2.6) per 10,000. Similar projections for other age and sex strata were also appreciated.

CONCLUSIONS

Intraoperative CT use significantly increases cancer risk compared with conventional intraoperative radiography for patients undergoing lumbar spinal fusions. As emerging technologies in spine surgery continue to proliferate and leverage intraoperative CT for cross-sectional imaging data, strategies must be developed by surgeons, institutions, and medical technology companies to mitigate long-term cancer risks.

Spinal artery syndrome following kyphoplasty in the setting of a non-compressive extradural cement extravasation: a case report

INTRODUCTION

Cement extravasation (CE) during vertebroplasty or kyphoplasty for vertebral compression fracture (VCF) is not uncommon, though neurological deficits occur rarely and when paraparesis occurs severe cord compression has been described. We report a case of progressive paraparesis in the setting of non-compressive extradural CE during kyphoplasty with evidence for spinal artery syndrome and neurological recovery after treatment.

CASE PRESENTATION

A 77-year-old female with T12 VCF failed conservative treatment and underwent kyphoplasty. In the recovery room, the patient was noted to have bilateral leg weakness, left worse than right, and had urgent CT scan that showed right paracentral CE without cord compression or arterial cement embolization. The patient was transferred to a tertiary hospital and had MRI of the spine that confirmed extradural CE and no cord compression. Because the patient had progression of lower extremity deficits despite medical management, she underwent surgical decompression, cement excision, and spinal fusion with instrumentation. Post op MRI showed T2 hyperintensities in the spinal cord consistent with spinal artery syndrome. One month post op, she had almost complete recovery of her neurological function.

DISCUSSION

Spinal artery syndrome may be considered in patients with neurological deficit s/p kyphoplasty even if the extravasated cement does not compress the spinal cord and even if the deficits are worse contralateral to the cement extravasation. If spinal artery syndrome is present and medical management does not improve the deficits, surgery may be indicated even if there is no cord compression.

Thoracolumbar Injury Classification Systems: The Importance of Concepts and Language in the Move Toward Standardization

STUDY DESIGN

Narrative review.

OBJECTIVE

To describe the evolution of acute traumatic thoracolumbar (TL) injury classification systems; to promote standardization of concepts and vocabulary with respect to TL injuries.

SUMMARY OF BACKGROUND DATA

Over the past century, numerous TL classification systems have been proposed and implemented, each influenced by the thought, imaging modalities, and surgical techniques available at the time. While much progress has been made in our understanding and management of these injuries, concepts, and terms are often intermixed, leading to potential confusion and miscommunication.

METHODS

We present a narrative review of the current state of the literature regarding classification systems for TL trauma.

RESULTS

The evolution of TL classification systems has broadly been characterized by a transition away from descriptive categorizations of fracture patterns to schema incorporating morphology, stability, and neurological function. In addition to these features, more recent systems have demonstrated the importance of predictive/prognostic capability, reliability, validity, and generalizability. The Arbeitsgemeinschaft fur Osteosynthesenfragen Spine Thoracolumbar Injury Classification System/Thoracolumbar Arbeitsgemeinschaft fur Osteosynthesenfragen Spine Injury Score represents the most modern and recently updated system, retiring past concepts and terminology in favor of clear, internationally agreed upon descriptors.

CONCLUSIONS

Advancements in our understanding of blunt TL trauma injuries have led to changes in management. Such advances are reflected in modern, dedicated classification systems. Over time, various key factors have been acknowledged and incorporated. In an effort to promote standardization of thought and language, past ideas and terminology should be retired.

Intraoperative CT for Lumbar Fusion Is Not Associated with Improved Short- or Long-Term Complication Profiles

BACKGROUND CONTEXT

The use of intraoperative CT has continued to grow in recent years, as various techniques leverage the promise of improved instrumentation accuracy and the hope for decreased complications. Nonetheless, the literature regarding the short- and long-term complications associated with such techniques remains scant and/or confounded by indication and selection bias.

PURPOSE

To use causal inference techniques to determine whether intraoperative CT use is associated with an improved complication profile as compared to conventional radiography for single-level lumbar fusions, an increasingly commonplace application for this technology.

STUDY DESIGN/SETTING

Inverse probability weighted retrospective cohort study carried out within a large integrated healthcare network PATIENT SAMPLE: Adult patients who underwent surgical treatment of spondylolisthesis via lumbar fusion from January 2016 through December 2021 OUTCOME MEASURES: Our primary outcome was the incidence rate of revision surgery. Our secondary outcome was the incidence of composite 90-day complications (deep and superficial surgical site infection, venous thromboembolic events, and unplanned readmissions).

METHODS

Demographics, intraoperative information, and postoperative complications were abstracted from electronic health records. A propensity score was developed utilizing a parsimonious model to account for covariate interaction with our primary predictor, intraoperative imaging technique. This propensity score was utilized in the creation of inverse probability weights to adjust for indication and selection bias. The rate of revisions within 3 years as well as the rate of revisions at any time-point were compared between cohorts using Cox regression analysis. The incidence of composite 90-day complications were compared using negative binomial regression.

RESULTS

Our patient population consisted of 583 patients, with 132 who underwent intraoperative CT and 451 who underwent conventional radiographic techniques. There were no significant differences between cohorts following inverse probability weighting. No significant differences were detected in 3-year revision rates (HR 0.74 [95% CI 0.29, 1.92]; p=0.5), overall revision rates (HR 0.54 [95% CI 0.20, 1.46]; p=0.2), or 90-day complications (RC -0.24 [95% CI -1.35, 0.87]; p=0.7).

CONCLUSIONS

Intraoperative CT use was not associated with an improved complication profile in either the short- or long-term for patients undergoing single-level instrumented fusion. This observed clinical equipoise should be weighed against resource and radiation-related costs when considering intraoperative CT for low complexity fusions.

Projected lifetime cancer risk for patients undergoing spine surgery for isthmic spondylolisthesis

BACKGROUND CONTEXT

Radiographs, fluoroscopy, and computed tomography (CT) are increasingly utilized in the diagnosis and management of various spine pathologies. Such modalities utilize ionizing radiation, a known cause of carcinogenesis. While the radiation doses such studies confer has been investigated previously, it is less clear how such doses translate to projected cancer risks, which may be a more interpretable metric.

PURPOSE

(1) Calculate the lifetime cancer risk and the relative contributions of preference-sensitive selection of imaging modalities associated with the surgical management of a common spine pathology, isthmic spondylolisthesis (IS); (2) Investigate whether the use of intraoperative CT, which is being more pervasively adopted, increases the risk of cancer.

STUDY DESIGN/SETTING

Retrospective cross-sectional study carried out within a large integrated health care network.

PATIENT SAMPLE

Adult patients who underwent surgical treatment of IS via lumbar fusion from January 2016 through December 2021.

OUTCOME MEASURES

(1) Effective radiation dose and lifetime cancer risk associated with each exposure to ionizing radiation; (2) Difference in effective radiation dose (and lifetime cancer risk) among patients who received intraoperative CT compared to other intraoperative imaging techniques.

METHODS

Baseline demographics and differences in surgical techniques were characterized. Radiation exposure data were collected from the 2-year period centered on the operative date. Projected risk of cancer from this radiation was calculated utilizing each patient's effective radiation dose in combination with age and sex. Generalized linear modeling was used to adjust for covariates when determining the comparative risk of intraoperative CT as compared to alternative imaging modalities.

RESULTS

We included 151 patients in this cohort. The range in calculated cancer risk exclusively from IS management was 1.3-13 cases of cancer per 1,000 patients. During the intraoperative period, CT imaging was found to significantly increase radiation exposure as compared to alternate imaging modalities (adjusted risk difference (ARD) 12.33mSv; IQR 10.04, 14.63mSv; p<.001). For a standardized 40 to 49-year-old female, this projects to an additional 0.72 cases of cancer per 1,000. For the entire 2-year perioperative care episode, intraoperative CT as compared to other intraoperative imaging techniques was not found to increase total ionizing radiation exposure (ARD 9.49mSv; IQR -0.83, 19.81mSv; p=.072). The effect of intraoperative imaging choice was mitigated in part due to preoperative (ARD 13.1mSv, p<.001) and postoperative CTs (ARD 22.7mSv, p<.001).

CONCLUSIONS

Preference-sensitive imaging decisions in the treatment of IS impart substantial cancer risk. Important drivers of radiation exposure exist in each phase of care, including intraoperative CT and/or CT scans during the perioperative period. Knowledge of these data warrant re-evaluation of current imaging protocols and suggest a need for the development of radiation-sensitive approaches to perioperative imaging.

The epidemiology and management of iliopsoas hematoma with femoral nerve palsy: A descriptive systematic review of 174 cases

INTRODUCTION

Iliopsoas hematoma with femoral nerve palsy is a rare phenomenon with no consensus treatment algorithm. The objective of this study was to perform a systematic review of all reported cases of femoral nerve palsy secondary to iliopsoas hematoma to better elucidate it's optimal treatment.

MATERIALS AND METHODS

Queries of the PubMed, Embase, and Cochrane databases were performed for reports available in English of femoral nerve palsy secondary to iliopsoas, psoas, or iliacus hematoma. 1491 articles were identified. After removal of duplicated publications and review of abstract titles via a majority reviewer consensus, 217 articles remained for consideration. Dedicated review of the remaining articles (including their reference sections) yielded 122 articles representing 174 distinct cases. Clinical data including patient age, sex, medical history, use of pharmacologic anticoagulation, sensory and motor examination at presentation and follow-up, hematoma etiology and location, time to intervention, and type of intervention were collected. Descriptive statistics were generated for each variable.

RESULTS

Femoral nerve palsy secondary to iliopsoas hematoma occurred at a mean age of 44.5 years old. A majority of patients (60%) were male, and a majority of hematomas (54%) occurred due to pharmacologic anticoagulation. Most hematomas (57%) were treated conservatively, and almost half (49%) - regardless of treatment modality - resulted in persistent motor deficits at final follow-up. A minority of patients treated surgically (34%) had residual motor deficit at final follow-up, while 66% of those treated medically had resultant motor deficits, although no direct statistical comparison was able to be performed.

DISCUSSION AND CONCLUSIONS

The disparate available data on iliopsoas hematoma with femoral nerve palsy precludes the completion of a true metanalysis, and therefore any conclusions on an optimal treatment algorithm. Based on review of the literature, small to moderate hematomas are often treated conservatively, while larger hematomas with progressive neurological symptoms are usually managed with a percutaneous decompression or surgery.

LEVEL OF EVIDENCE

IV.

Surgical Intervention is Associated With Improvements in the ASIA Impairment Scale in Gunshot-induced Spinal Injuries of the Thoracic and Lumbar Spine

STUDY DESIGN

Retrospective cohort study of patients from the National Spinal Cord Injury Statistical Center (NSCISC).

OBJECTIVE

The aim was to compare the outcomes of patients with gunshot-induced spinal injuries (GSIs) treated operatively and nonoperatively.

SUMMARY OF BACKGROUND DATA

The treatment of neurological deficits associated with gunshot wounds to the spine has been controversial. Treatment has varied widely, ranging from nonoperative to aggressive surgery.

METHODS

Patient demographics, clinical information, and outcomes were extracted. Surgical intervention was defined as a "laminectomy, neural canal restoration, open reduction, spinal fusion, or internal fixation of the spine." The primary outcome was the American Spinal Injury Association (ASIA) Impairment Scale. Statistical comparisons of baseline demographics and neurological outcomes between operative and nonoperative cohorts were performed.

RESULTS

In total, 961 patients with GSI and at least 1-year follow-up were identified from 1975 to 2015. The majority of patients were Black/African American (55.6%), male (89.7%), and 15-29 years old (73.8%). Of those treated surgically (19.7% of all patients), 34.2% had improvement in their ASIA Impairment Scale score at 1 year, compared with 20.6% treated nonoperatively. Overall, surgery was associated with a 2.0 [95% confidence interval (CI): 1.4-2.8] times greater likelihood of ASIA Impairment Scale improvement at 1 year. Specifically, benefit was seen in thoracic (odds ratio: 2.5; 95% CI: 1.4-4.6) and lumbar injuries (odds ratio: 1.7; 95% CI: 1.1-3.1), but not cervical injuries.

CONCLUSIONS

While surgical indications are always determined on an individualized basis, in our review of GSIs, surgical intervention was associated with a greater likelihood of neurological recovery. Specifically, patients with thoracic and lumbar GSIs had a 2.5 and 1.7-times greater likelihood of improvement in their ASIA Impairment Scale score 1 year after injury, respectively, if they underwent surgical intervention.

ALIF Versus TLIF for L5-S1 Isthmic Spondylolisthesis: ALIF Demonstrates Superior Segmental and Regional Radiographic Outcomes and Clinical Improvements Across More Patient-reported Outcome Measures Domains

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of this study was to compare segmental and regional radiographic parameters between anterior interbody fusion (ALIF) and posterior interbody fusion (TLIF) for treatment of L5-S1 isthmic spondylolisthesis, and to assess for changes in these parameters over time. Secondarily, we sought to compare clinical outcomes via patient-reported outcome measures (PROMs) between techniques and within groups over time.

SUMMARY OF BACKGROUND DATA

Isthmic spondylolistheses are frequently treated with interbody fusion via ALIF or TLIF approaches. Robust comparisons of radiographic and clinical outcomes are lacking.

METHODS

We reviewed pre- and postoperative radiographs as well as Patient-Reported Outcomes Measurement Information System (PROMIS) elements for patients who received L5-S1 interbody fusions for isthmic spondylolisthesis in the Mass General Brigham (MGB) health system (2016-2020). Intraclass correlation testing was used for reliability assessments; Mann-Whitney U tests and Sign tests were employed for intercohort and intracohort comparative analyses, respectively.

RESULTS

ALIFs generated greater segmental and L4-S1 lordosis than TLIF, both at first postoperative visit (mean 26 days [SE = 4]; 11.3° vs. 1.3°, P  < 0.001; 6.2° vs. 0.3°, P  = 0.005) and at final follow-up (mean 410days [SE = 45]; 9.6° vs. 0.2°, P < 0.001; 7.9° vs. 2.1°, P = 0.005). ALIF also demonstrated greater increase in disc height than TLIF at first (9.6 vs. 5.5 mm, P < 0.001) and final follow-up (8.7 vs. 3.6 mm, P < 0.001). Disc height was maintained in the ALIF group but decreased over time in the TLIF cohort (ALIF 9.6 vs. 8.7 mm, P = 0.1; TLIF 5.5 vs. 3.6 mm, P < 0.001). Both groups demonstrated improvements in Pain Intensity and Pain Interference scores; ALIF patients also improved in Physical Function and Global Health - Physical domains.

CONCLUSION

ALIF generates greater segmental lordosis, regional lordosis, and restoration of disc height compared to TLIF for treatment of isthmic spondylolisthesis. Additionally, ALIF patients demonstrate significant improvements across more PROMs domains relative to TLIF patients.Level of Evidence: 3.

A Clinical Risk Model for Surgical Site Infection Following Pediatric Spine Deformity Surgery

BACKGROUND

Despite tremendous efforts, the incidence of surgical site infection (SSI) following the surgical treatment of pediatric spinal deformity remains a concern. Although previous studies have reported some risk factors for SSI, these studies have been limited by not being able to investigate multiple risk factors at the same time. The aim of the present study was to evaluate a wide range of preoperative and intraoperative factors in predicting SSI and to develop and validate a prediction model that quantifies the risk of SSI for individual pediatric spinal deformity patients.

METHODS

Pediatric patients with spinal deformity who underwent primary, revision, or definitive spinal fusion at 1 of 7 institutions were included. Candidate predictors were known preoperatively and were not modifiable in most cases; these included 31 patient, 12 surgical, and 4 hospital factors. The Centers for Disease Control and Prevention definition of SSI within 90 days of surgery was utilized. Following multiple imputation and multicollinearity testing, predictor selection was conducted with use of logistic regression to develop multiple models. The data set was randomly split into training and testing sets, and fivefold cross-validation was performed to compare discrimination, calibration, and overfitting of each model and to determine the final model. A risk probability calculator and a mobile device application were developed from the model in order to calculate the probability of SSI in individual patients.

RESULTS

A total of 3,092 spinal deformity surgeries were included, in which there were 132 cases of SSI (4.3%). The final model achieved adequate discrimination (area under the receiver operating characteristic curve: 0.76), as well as calibration and no overfitting. Predictors included in the model were nonambulatory status, neuromuscular etiology, pelvic instrumentation, procedure time ≥7 hours, American Society of Anesthesiologists grade >2, revision procedure, hospital spine surgical cases <100/year, abnormal hemoglobin level, and overweight or obese body mass index.

CONCLUSIONS

The risk probability calculator encompassing patient, surgical, and hospital factors developed in the present study predicts the probability of 90-day SSI in pediatric spinal deformity surgery. This validated calculator can be utilized to improve informed consent and shared decision-making and may allow the deployment of additional resources and strategies selectively in high-risk patients.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Does Operative Management of Epidural Abscesses Increase Healthcare Expenditures up to 1 Year After Treatment?

BACKGROUND

The incidence of spinal epidural abscesses is increasing. What is more, they are associated with high rates of morbidity and mortality. Advances in diagnostic imaging and antibiotic therapies have made earlier diagnosis and nonoperative management feasible in appropriately selected patients. Nonoperative treatment also has the advantage of lower immediate healthcare charges; however, it is unknown whether initial nonoperative care leads to higher healthcare charges long term.

QUESTIONS/PURPOSES

(1) Does operative intervention generate higher charges than nonoperative treatment over the course of 1 year after the initial treatment of spinal epidural abscesses? (2) Does the treatment of spinal epidural abscesses in people who actively use intravenous drugs generate higher charges than management in people who do not?

METHODS

This retrospective comparative study at two tertiary academic centers compared adult patients with spinal epidural abscesses treated operatively and nonoperatively from January 2016 through December 2017. Ninety-five patients were identified, with four excluded for lack of billing data and one excluded for concomitant intracranial abscess. Indications for operative management included new or progressive motor deficit, lack of response to nonoperative treatment including persistent or progressive systemic illness, or initial sepsis requiring urgent source control. Of the included patients, 52% (47 of 90) received operative treatment with no differences in age, gender, BMI, and Charlson comorbidity index between groups, nor any difference in 30-day all-cause readmission rate, 1-year reoperation rate, or 2-year mortality. Furthermore, 29% (26 of 90) of patients actively used intravenous drugs and were younger, with a lower BMI and lower Charlson comorbidity index, with no differences in 30-day all-cause readmission rate, 1-year reoperation rate, or 2-year mortality. Cumulative charges at the index hospital discharge and 90 days and 1 year after discharge were compared based on operative or nonoperative management and secondarily by intravenous drug use status. Medical records, laboratory results, and hospital billing data were reviewed for data extraction. Demographic factors including age, gender, region of abscess, intravenous drug use, and comorbidities were extracted, along with clinical factors such as symptoms and ambulatory function at presentation, spinal instability, intensive care unit admission, and complications. The primary outcome was charges associated with care at the index hospital discharge and 90 days and 1 year after discharge. All covariates extracted were included in this analysis using negative binomial regression that accounted for confounders and the nonparametric nature of charge data. Results are presented as an incidence rate ratio with 95% confidence intervals.

RESULTS

After adjusting for demographic and clinical variables such as age, gender, BMI, ambulatory status, presence of mechanical instability, and intensive care unit admission among others, we found higher charges for the group treated with surgery compared with those treated nonoperatively at the index admission (incidence rate ratio [IRR] 1.62 [95% CI 1.35 to 1.94]; p < 0.001) and at 1 year (IRR 1.36 [95% CI 1.10 to 1.68]; p = 0.004). Adjusted analysis also showed that active intravenous drug use was also associated with higher charges at the index admission (IRR 1.57 [95% CI 1.16 to 2.14]; p = 0.004) but no difference at 1 year (IRR 1.11 [95% CI 0.79 to 1.57]; p = 0.55).

CONCLUSION

Multidisciplinary teams caring for patients with spinal epidural abscesses should understand that the decreased charges associated with selecting nonoperative management during the index admission persist at 1 year with no difference in 30-day readmission rates, 1-year reoperation rates, or 2-year mortality. On the other hand, patients with active intravenous drug use have higher index admission charges that do not persist at 1 year, with no difference in 30-day readmission rates, 1-year reoperation rates, or 2-year mortality. These results suggest possible economic benefit to nonoperative management of epidural abscesses without increases in readmission or mortality rates, further tipping the scale in an evolving framework of clinical decision-making. Future studies should investigate if these economic implications are mirrored on the patient-facing side to determine whether any financial burden is shifted onto patients and their families in nonoperative management.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Early Weight Bearing after Distal Femur Fracture Fixation

Objectives

To assess outcomes following early weight bearing after distal femur fracture fixation with locked lateral plating.

Design

Retrospective cohort study

Setting

Two Level 1 Academic Trauma Centers.

Patients/Participants

Patients 18 years and older with distal femur fractures treated with locked lateral plating

Intervention

Early full weight bearing (defined as less than 30 days from date of surgery) versus restricted post-operative weight bearing

Main Outcome Measurements

Composite complication comprising malunion, nonunion, surgical site infection, re-admission, or death

Results

270 distal femur fractures were reviewed, with 165 meeting inclusion criteria. 21 patients had been allowed early full weight bearing. Fractures were divided into two groups based on when full weight bearing was allowed post-operatively. The two groups had similar fractures as determined by the distribution of AO distal femur fracture and Su periprosthetic femur fracture classifications. The early weight bearing group was significantly older and more comorbid. Despite being older, more comorbid, and allowed early full weight bearing on their fracture fixation construct, there was no difference in the rate of composite complications between groups.

Conclusion

Our data contributes to the small, but growing body of literature that has found no increased rate of fracture related complications in surgically treated distal femur fractures allowed early post-operative weight bearing.

Level of Evidence

Therapeutic Level III Study.

Telemedicine visits generate accurate surgical plans across orthopaedic subspecialties

INTRODUCTION

The role of telemedicine is rapidly evolving across medical specialties and orthopaedics. The utility of telemedicine to identify operative candidates and determine surgical plans has yet to be demonstrated. We sought to assess whether surgical plans proposed following telemedicine visits changed after subsequent in-person interaction across orthopaedic subspecialties.

MATERIALS AND METHODS

We identified all elective telemedicine encounters across two academic institutions from March 1, 2020 to July 31, 2020. We identified patients indicated for surgery with a specific surgical plan during the virtual visit. The surgical plans delineated during the telemedicine encounter were then compared to final pre-operative plans documented following subsequent in-person evaluation. Changes in the surgical plan between telemedicine and in-person encounters were defined using a standardised schema. Regression analysis was used to evaluate factors associated with a change in surgical plan between visits across specialties, including the number of virtual examination manoeuvres performed.

RESULTS

We identified 303 instances of a patient being indicated for orthopaedic surgery during a telemedicine encounter. In 11 cases (4%), the plan was changed between telemedicine and subsequent in-person encounter. No plans were changed amongst patients indicated for joint arthroplasty and foot and ankle surgery, whilst 4% of plans were changed amongst sports surgery and upper extremity/shoulder surgery. Surgical plans had the highest rate of change amongst spine surgery patients (8%). There was notable variability in the conduct of virtual examinations across subspecialties.

CONCLUSION

Our results demonstrate the capability of telemedicine to support development of accurate surgical plans for orthopaedic patients across several subspecialties. Our findings also highlight the substantial variation in the utilisation of physical examination manoeuvres conducted via telemedicine across institutions, subspecialties, and providers.

DESCRIPTION OF STUDY TYPE

Level IV, retrospective cohort study.

Comparison of Radiation Exposure Between Anterior, Lateral, and Posterior Interbody Fusion Techniques and the Influence of Patient and Procedural Factors

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The aim of this study was to elucidate the relative influence of multiple factors on radiation usage for anterior, lateral, and posterior based lumbar interbody fusion techniques.

SUMMARY OF BACKGROUND DATA

There has been substantial global growth in the performance of lumbar interbody fusions, due to evolution of techniques and approaches and increased attention to sagittal alignment. Utilization of intraoperative imaging guidance has similarly expanded, with a predominance of fluoroscopy and consequent increased radiation exposure. There have been no larger-scale studies examining the role of patient and procedural factors in driving radiation exposure across different interbody techniques.

METHODS

We used a clinical registry to review all single-level lumbar interbody fusions performed between January 2016 and October 2020. Operative records were reviewed for the amount of radiation exposure during the procedure. Patient age, biologic sex, body mass index (BMI), operative surgeon, surgical level, surgical time, and fusion technique were recorded. Multivariable adjusted analyses using negative binomial regression were used to account for confounding.

RESULTS

We included 134 interbody fusions; 80 performed with a posterior approach (TLIF/PLIF), 43 via an anterior approach (ALIF) with posterior pedicle fixation, and 9 performed with a lateral approach (LLIF/XLIF). Average radiation per case was 136.4 mGy (SE 17.3) for ALIF, 108.6 mGy (16.9) for LLIF/XLIF, and 60.5 mGy (7.4) for TLIF/PLIF. We identified lateral approaches, increased BMI, minimally invasive techniques, and more caudal operative levels as significantly associated with increased radiation exposure.

CONCLUSION

We identified several novel drivers of radiation exposure during interbody fusion procedures, including the relative importance of technique and the level at which the fusion is performed. More caudal levels of intervention and lateral based techniques had significantly greater radiation exposure.Level of Evidence: 4.

A Novel Shorthand Approach to Knee Bone Age Using MRI: A Validation and Reliability Study

Background:

Bone-age determination remains a difficult process. An atlas for bone age has been created from knee-ossification patterns on magnetic resonance imaging (MRI), thereby avoiding the need for radiographs and associated costs, radiation exposure, and clinical inefficiency. Shorthand methods for bone age can be less time-consuming and require less extensive training as compared with conventional methods.

Purpose:

To create and validate a novel shorthand algorithm for bone age based on knee MRIs that could correlate with conventional hand bone age and demonstrate reliability across medical trainees.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

Included in this study were adolescent patients who underwent both knee MRI and hand bone age radiographs within 90 days between 2009 and 2018. A stepwise algorithm for predicting bone age using knee MRI was developed separately for male and female patients, and 7 raters at varying levels of training used the algorithm to determine the bone age for each MRI. The shorthand algorithm was validated using Spearman rho (r_S) to correlate each rater’s predicted MRI bone age with the recorded Greulich and Pyle (G&P) hand bone age. Interrater and intrarater reliability were also calculated using intraclass correlation coefficients (ICCs).

Results:

A total of 38 patients (44.7% female) underwent imaging at a mean age of 12.8 years (range, 9.3-15.7 years). Shorthand knee MRI bone age scores were strongly correlated with G&P hand bone age (r_S = 0.83; P < .001). The shorthand algorithm was a valid predictor of G&P hand bone age regardless of level of training, as medical students (r_S = 0.75), residents (r_S = 0.81), and attending physicians (r_S = 0.84) performed similarly. The interrater reliability of our shorthand algorithm was 0.81 (95% CI, 0.73-0.88), indicating good to excellent interobserver agreement. Respondents also demonstrated consistency, with 6 of 7 raters demonstrating excellent intrarater reliability (median ICC, 0.86 [range, 0.68-0.96]).

Conclusion:

This shorthand algorithm is a consistent, reliable, and valid way to determine skeletal maturity using knee MRI in patients aged 9 to 16 years and can be utilized across different levels of orthopaedic and radiographic expertise. This method is readily applicable in a clinical setting and may reduce the need for routine hand bone age radiographs.

Telemedicine Use in Orthopaedic Surgery Varies by Race, Ethnicity, Primary Language, and Insurance Status

BACKGROUND

Healthcare disparities are well documented across multiple subspecialties in orthopaedics. The widespread implementation of telemedicine risks worsening these disparities if not carefully executed, despite original assumptions that telemedicine improves overall access to care. Telemedicine also poses unique challenges such as potential language or technological barriers that may alter previously described patterns in orthopaedic disparities.

QUESTIONS/PURPOSES

Are the proportions of patients who use telemedicine across orthopaedic services different among (1) racial and ethnic minorities, (2) non-English speakers, and (3) patients insured through Medicaid during a 10-week period after the implementation of telemedicine in our healthcare system compared with in-person visits during a similar time period in 2019?

METHODS

This was a retrospective comparative study using electronic medical record data to compare new patients establishing orthopaedic care via outpatient telemedicine at two academic urban medical centers between March 2020 and May 2020 with new orthopaedic patients during the same 10-week period in 2019. A total of 11,056 patients were included for analysis, with 1760 in the virtual group and 9296 in the control group. Unadjusted analyses demonstrated patients in the virtual group were younger (median age 57 years versus 59 years; p < 0.001), but there were no differences with regard to gender (56% female versus 56% female; p = 0.66). We used self-reported race or ethnicity as our primary independent variable, with primary language and insurance status considered secondarily. Unadjusted and multivariable adjusted analyses were performed for our primary and secondary predictors using logistic regression. We also assessed interactions between race or ethnicity, primary language, and insurance type.

RESULTS

After adjusting for age, gender, subspecialty, insurance, and median household income, we found that patients who were Hispanic (odds ratio 0.59 [95% confidence interval 0.39 to 0.91]; p = 0.02) or Asian were less likely (OR 0.73 [95% CI 0.53 to 0.99]; p = 0.04) to be seen through telemedicine than were patients who were white. After controlling for confounding variables, we also found that speakers of languages other than English or Spanish were less likely to have a telemedicine visit than were people whose primary language was English (OR 0.34 [95% CI 0.18 to 0.65]; p = 0.001), and that patients insured through Medicaid were less likely to be seen via telemedicine than were patients who were privately insured (OR 0.83 [95% CI 0.69 to 0.98]; p = 0.03).

CONCLUSION

Despite initial promises that telemedicine would help to bridge gaps in healthcare, our results demonstrate disparities in orthopaedic telemedicine use based on race or ethnicity, language, and insurance type. The telemedicine group was slightly younger, which we do not believe undermines the findings. As healthcare moves toward increased telemedicine use, we suggest several approaches to ensure that patients of certain racial, ethnic, or language groups do not experience disparate barriers to care. These might include individual patient- or provider-level approaches like expanded telemedicine schedules to accommodate weekends and evenings, institutional investment in culturally conscious outreach materials such as advertisements on community transport systems, or government-level provisions such as reimbursement for telephone-only encounters.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Variability and contributions to cost associated with anterior versus posterior approaches to lumbar interbody fusion

OBJECTIVE

Lumbar interbody fusions are being performed with increased frequency in the last decade. Anterior and posterior interbody techniques have demonstrated relatively similar success rates. Nonetheless, despite increased attention to cost-effective care delivery, approach-related differences in procedural cost and predictors for these differences remain poorly defined. The purpose of this investigation was to characterize the variability in cost for anterior versus posterior-based lumbar interbody fusions and to identify key predictors of procedural cost.

METHODS

We evaluated the records of all patients who underwent a primary anterior (ALIF) or posterior/transforaminal (PLIF/TLIF) lumbar interbody fusion with concomitant posterior fusion from 2016 to 2020 at four hospitals in a major metropolitan area. We reviewed the records of all included patients and abstracted demographics, insurance status, approach, operative time, diagnosis, surgeon, institution, open versus minimally invasive technique, and components of procedural costs. Costs based upon interbody approach were compared via multivariable adjusted analyses using negative binomial regression.

RESULTS

We included 139 interbody fusion procedures; 98 were performed via posterior approach (TLIF/PLIF) and 41 using an anterior approach. Anterior techniques were associated with significantly increased costs as compared to posterior procedures (anterior, $16316 [SE 556] vs. posterior, $9415 [SE 345]; p < 0.001). This determination remained significant following multivariable adjusted analysis (regression coefficient -0.22, 95% CI -0.34, -0.10, p < 0.001). Multivariable analysis also indicated that surgeon, invasiveness, and procedure time were significant predictors of total cost.

CONCLUSION

Our findings demonstrate that anterior interbody techniques are, on average, 173% (anterior, $16316 [SE 556] vs. posterior, $9415 [SE 345]; p < 0.001) more expensive than posterior-based procedures. Given the relative equipoise of these different approaches for many clinical applications, these findings should be considered in an ecosystem increasingly attentive to cost effective care delivery. This work has also provided specific procedural variables for surgeons and systems to target when optimizing procedural costs.

Interventional procedure plans generated by telemedicine visits in spine patients are rarely changed after in-person evaluation

BACKGROUND AND OBJECTIVES

The role of telemedicine in the evaluation and treatment of patients with spinal disorders is rapidly expanding, brought on largely by the COVID-19 pandemic. Within this context, the ability of pain specialists to accurately diagnose and plan appropriate interventional spine procedures based entirely on telemedicine visits, without an in-person evaluation, remains to be established. In this study, our primary objective was to assess the relevance of telemedicine to interventional spine procedure planning by determining whether procedure plans established solely from virtual visits changed following in-person evaluation.

METHODS

We reviewed virtual and in-person clinical encounters from our academic health system's 10 interventional spine specialists. We included patients who were seen exclusively via telemedicine encounters and indicated for an interventional procedure with documented procedural plans. Virtual plans were then compared with the actual procedures performed following in-person evaluation. Demographic data as well as the type and extent of physical examination performed by the interventional spine specialist were also recorded.

RESULTS

Of the 87 new patients included, the mean age was 60 years (SE 1.4 years) and the preprocedural plan established by telemedicine, primarily videoconferencing, did not change for 76 individuals (87%; 95% CI 0.79 to 0.94) following in-person evaluation. Based on the size of our sample, interventional procedures indicated solely during telemedicine encounters may be accurate in 79%-94% of cases in the broader population.

CONCLUSIONS

Our findings suggest that telemedicine evaluations are a generally accurate means of preprocedural assessment and development of interventional spine procedure plans. These findings clearly demonstrate the capabilities of telemedicine for evaluating spine patients and planning interventional spine procedures.

Spontaneous iliacus haematoma with femoral nerve palsy: an appeal to involve surgical teams early

We report the case of a 68-year-old man who was placed on heparin as bridge therapy and subsequently developed an iliacus haematoma with associated femoral nerve palsy. His team involved the orthopaedic surgery team in delayed fashion after his symptom onset. Due to his active medical conditions, he did not undergo surgical decompression of his haematoma until late into his hospital course. Unfortunately, this patient did not regain meaningful function from his femoral nerve deficit. We believe this case highlights the high index of suspicion necessary for making this diagnosis as well as the repercussions of an untimely decompression for this acute, compressive neuropathy. Although we are surgeons and this is a surgical case, we hope to publish this case in a medical journal to raise awareness that surgical decompression does have a role in this diagnosis and should ultimately be pursued early in its course for optimal patient benefit.

Complications and Controversies in the Management of 5 Common Pediatric Sports Injuries

Growing participation in sports among children, along with increasingly intense training regimens, has contributed to an increasing rate of sports-related injuries. Despite the similarities to adult sports injuries, pediatric patients have distinctive injury patterns because of the growing physis and therefore necessitate unique treatment algorithms. Caring for these injured children requires in-depth knowledge of not only pediatric injury patterns, but also the scope of age-specific treatments, the associated complications, and the controversies. When treating motivated pediatric athletes, one must be able to strike a delicate balance between patients' eagerness to return to sport and the need to ensure their long-term health and function. Knowledge of controversies and complications will help both patients and physicians make informed decisions about how best to restore pediatric athletes back to health.

Laminoplasty versus laminectomy and fusion for cervical spondylotic myelopathy: a cost analysis

BACKGROUND CONTEXT

Laminectomy with fusion (LF) and laminoplasty (LP) are commonly used to treat cervical spondylotic myelopathy (CSM). The decision regarding which procedure to perform is largely a matter of surgeon's preference, while financial implications are rarely considered.

PURPOSE

We aimed to better understand the financial considerations of LF compared to LP in the treatment of CSM.

STUDY DESIGN

Retrospective comparative study.

PATIENT SAMPLE

Adult patients, 18 years of age or older, who had undergone LF or LP for CSM from 2017 to 2019 at 2 large academic centers were included. Patients who had undergone previous cervical spine surgery or procedures that extended above C2 or below T2 were excluded.

OUTCOME MEASURES

The primary outcome was defined as the total cost of the procedure, which was calculated as the sum of the implant and non-implant supply costs.

METHODS

Patient demographics, surgical parameters, including estimated blood loss and operative time, and length of stay were collected. Operating room material - both implant and non-implant - cost data was also obtained. Variables were analyzed individually as well as after adjustment based on the number of operative levels involved. Statistical analysis was performed using either Student t test with unequal variance or Wilcoxon rank sum test for continuous variables and chi-squared analysis for categorical variables.

RESULTS

Two hundred fifty patients were identified who met inclusion criteria. There was no statistical difference in the mean age at time of surgery (p=.25), gender distribution (p=.33), or re-operation rate between the LF and LP groups (p=.39). Overall, operative time was similar between the LF (165.7 ± 61.9 min) and LP (173.8 ± 58.2 min) groups (p=.29), but the LP cohort had a shorter length of stay at 3.8 ± 2.7 days compared to the LF cohort at 4.8 ± 3.7 days. Implant costs in the LF group were significantly more at $6,204.94 ± $1426.41 compared to LP implant costs at $1994.39 ± $643.09. Mean total costs of LP were significantly less at $2,859.08 ± $784.19 compared to LF total costs of $6,983.16 ± $1,589.17. Furthermore, when adjusted for the number of operative levels, LP remained significantly less costly at $766.12 ± $213.64 per level while LF cost $1,789.05 ± $486.66 per operative level. Additional subgroup analysis limiting the cohorts to patients with either three or four involved vertebral levels demonstrated nearly identical cost savings with LP as compared to LF.

CONCLUSIONS

This study demonstrates that LF is on average at least 2.4 times the total operative supply cost of LP and at least 2.3 times the operative supply cost of LP when adjusted for the number of operative levels. In patients deemed appropriate for either LP or LF, these data may be incorporated into decision-making for the treatment of CSM.

Displaced Supracondylar Humerus Fractures in Toddlers

Gartland type III fracture is the most troublesome type of supracondylar humerus fracture. These injuries most often occur in school age children, but they are seen in pediatric patients of all ages. The goal of this study was to analyze toddlers with Gartland type III fractures to identify clinically significant differences compared with older children. A retrospective cohort study was conducted with 94 toddlers (<3 years) and 378 older children (3 to 12 years). Factors including demographics, mechanism of injury, additional injuries, location of trauma, pin configuration, postoperative complications, follow-up time, and compliance with the treatment plan were collected and compared. The study included 94 toddlers (59% girls, 2.11±0.64 years) and 378 older children (48% girls, 6.32±1.89 years), chosen at random, who were treated between 2000 and 2015. Among toddlers, fractures were more likely to occur at home (P<.001) and to be the result of suspected nonaccidental trauma (P<.001). Older children had more additional injuries (P<.001), but were no more likely to have an open fracture (P=.59) or a flexion-type fracture (P=.42). Older children were more likely to undergo open reduction (P=.03), whereas toddlers were more likely to be treated with a medial pin (P<.001). Toddlers experienced more cubitus varus (P<.001) and loss of reduction (P=.02). No difference was found in length of follow-up (P=.83) or compliance with the treatment plan (P=.11). This study provides novel insights into clinical differences between toddlers and older children with Gartland type III fractures. Knowledge of these differences can facilitate the delivery of targeted, age-specific care for patients with type III supracondylar humerus fractures. [Orthopedics. 2020;43(5);e421-e424.].

Bisphosphonates and parathyroid hormone analogs for improving bone quality in spinal fusion: State of evidence

Spinal fusion is among the most commonly performed surgical procedures for elderly patients with spinal disorders - including degenerative disc disease with spondylolisthesis, deformities, and trauma. With the large increase in the aging population and the prevalence of osteoporosis, the number of elderly osteoporotic patients needing spinal fusion has risen dramatically. Due to reduced bone quality, postoperative complications such as implant failures, fractures, post-junctional kyphosis, and pseudarthrosis are more commonly seen after spinal fusion in osteoporotic patients. Therefore, pharmacologic treatment strategies to improve bone quality are commonly pursued in osteoporotic cases before conducting spinal fusions. The two most commonly used pharmacotherapeutics are bisphosphonates and parathyroid hormone (PTH) analogs. Evidence indicates that using bisphosphonates and PTH analogs, alone or in combination, in osteoporotic patients undergoing spinal fusion, decreases complication rates and improves clinical outcomes. Further studies are needed to develop guidelines for the administration of bisphosphonates and PTH analogs in osteoporotic spinal fusion patients in terms of treatment duration, potential benefits of sequential use, and the selection of either therapeutic agents based on patient characteristics.

An In-Depth Analysis of Graft Rupture and Contralateral Anterior Cruciate Ligament Rupture Rates After Pediatric Anterior Cruciate Ligament Reconstruction

BACKGROUND

Reported rates of graft rupture and contralateral anterior cruciate ligament (ACL) rupture after ACL reconstruction (ACLR) are higher among pediatric patients than adults. Previous series may have underestimated postoperative event risk because of small sample sizes and high proportions of dropouts.

PURPOSE

To calculate rates of graft rupture and contralateral ACL rupture after ACLR in a large pediatric series.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

ACLRs performed in our tertiary care children's hospital system over a period of >7 years were identified through billing review. Cases were sorted based on operative technique, with all-epiphyseal ACLRs considered separately. Transphyseal ACLRs were divided into 2 groups based on patient age, with a cutoff of 16 years. Clinic follow-up data as well as prospectively collected survey data were used to note graft rupture and contralateral ACL rupture events. Rates of graft rupture and contralateral ACL rupture were calculated using Kaplan-Meier survival analysis.

RESULTS

The final data set included 996 patients. A total of 161 patients underwent all-epiphyseal ACLR. Of the remaining transphyseal surgeries, 504 patients were <16 years of age at the time of surgery and 331 were ≥16 years. The 4-year cumulative rate of graft rupture via Kaplan-Meier survival analysis was 19.7% among all patients. The rate was 18.2% among all-epiphyseal ACLRs, 21.6% among transphyseal ACLRs in patients <16 years, and 16.4% among transphyseal ACLRs in patients ≥16 years (P = .855). Survival analysis estimated the 4-year cumulative rate of contralateral ACL rupture at 12.0% among all patients: 6.63% among all-epiphyseal ACLRs, 15.7% among transphyseal ACLRs in patients <16 years, and 8.05% among transphyseal ACLRs in patients ≥16 years (P = .093).

CONCLUSION

This is the largest series of pediatric ACLRs yet reported, and it shows that the risks of another ACL injury after first-time ACLR are higher than previously reported. The risk of contralateral ACL rupture was lower than that for graft rupture. Our methods, including prospective follow-up surveys and survival analysis to generate cumulative rate estimates, provide a best-practice example for future case series calculations. Our results provide insight into the postoperative course of pediatric patients undergoing ACLR and are crucial for preoperative patient and family counseling. Understanding these risks may also influence return-to-play decisions.

Fate of Hardware in Spinal Infections

Background: Removal of hardware with irrigation and debridement in patients with surgical site infections (SSIs) is performed commonly. However, the removal of hardware from patients with SSIs after spinal procedures is controversial. Moreover, primary spinal infections such as spondylodiscitis may require instrumentation along with surgical debridement. The purpose of this article was to evaluate critically and summarize the available evidence related to retention of hardware in patients with deep SSIs, and the use of instrumentation in surgical treatment of primary spinal infections. Methods: A literature search utilizing PubMed database was performed. Studies reporting the management of deep SSIs after instrumented spinal procedures, and of primary spinal infections using instrumentation published in peer-reviewed journals were included. Identified publications were evaluated for relevance, and data were extracted from the studies deemed relevant. Results: Because SSIs occur typically during the early post-operative period before stable bony fusion has been achieved, the removal of instrumentation may be associated with instability of the spinal column, pseudarthrosis, progressive deformity, pain, loss of function, and deterioration in the activities of daily living (ADL). Hence, early SSIs after spinal instrumentation are usually treated without removal of hardware. Moreover, primary spinal infections such as spondylodiscitis may require surgical debridement and instrumentation in cases with associated instability. Conclusions: Retaining or using instrumentation in patients with SSIs after spinal procedures or in patients with primary spinal infections, respectively, are commonly practiced in the field of spine surgery. Further evidence is required for the development of definitive algorithms to guide spine surgeons in decision making regarding the fate of instrumentation in the treatment of spinal infections.

Site-specific Surgical Site Infection Rates for Rib-based Distraction

BACKGROUND

Implantable rib-based distraction devices have revolutionized the treatment of children with early onset scoliosis and thoracic insufficiency syndrome. Unfortunately, the need for multiple skin incisions and repeated surgeries in a fragile patient population creates considerable infection risk. In order to assess rates of infection for different incision locations and potential risk factors, we generated a prospectively collected database of patients treated with rib-based distraction devices.

METHODS

We analyzed a cohort of patients with thoracic insufficiency syndrome from various etiologies that our institution treated with rib-based distraction devices from 2013 to 2016. Surgery type (implantation, expansion, revision/removal), and surgeon adjudicated surgical site infection (SSI) were collected. For this study, we developed a novel, rib-based distraction device surgical site labeling system in which incisions could be labeled as either proximal or distal surgical exposure areas. Treating surgeons documented the operative site, procedure, and SSI site in real-time.

RESULTS

A total of 166 unique patients underwent 670 procedures during the study period, producing 1537 evaluable surgical sites; 1299 proximal and 238 distal. Patients were 6.81±4.0 years of age on average. Forty-seven procedures documented SSIs (7.0%), while 40 (24.1%) patients experienced an infection. Analysis showed significant variation in the rate of infection between implantation, and expansion, and revision procedures, with implantation procedures having the highest infection rate at 13.1% (P<0.01). Infections occurred more frequently at distal sites than proximal ones (P=0.02).

CONCLUSIONS

Our novel, surgeon-entered, prospective quality improvement database has identified distal surgical sites as being at higher risk for SSI than proximal ones. Further, rib-based distraction device implantation procedures were identified as being at a greater risk for SSI than expansion or revision procedures. We believe this data can lead to improved prevention measures, anticipatory guidance, and patient care.

LEVEL OF EVIDENCE

Level II-prognostic study.

Operative Time and Cost Vary by Surgeon: An Analysis of Supracondylar Humerus Fractures in Children

Operative time is a critical driver of cost in orthopedics and an important target for improving value in health care. This study used an archetypal pediatric orthopedic procedure to identify surgeon-dependent variability in operative time. The authors reviewed patients 12 years or younger treated with closed reduction and percutaneous pinning for extension-type supracondylar humerus fractures. Variability in operative time across surgeons was assessed. Surgeon experience at the time of the procedure and case volume (quarterly) were evaluated to explain variations in operative time. A total of 1472 patients were reviewed (57% Gartland type II and 43% type III fractures). Procedures were performed by 12 fellowship-trained pediatric orthopedists with 2 weeks to 32.8 years of experience. For individual surgeons, the mean operative time ranged from 20.4 to 33.7 minutes for type II fractures and from 31.0 to 46.8 minutes for type III fractures. There was significant variation across surgeons in mean operative time and cost (P<.001). Analysis showed no significant effect of surgeon experience or quarterly case volume. Surgeons' mean operative time for type II fractures was strongly positively correlated with their mean operative time for type III fractures (r²=0.74). Mean operative time and cost for supracondylar humerus fracture closed reduction and percutaneous pinning vary significantly between surgeons, but this variation is not explained by experience or volume. Surgeons who required more time for type II fractures were also slower for type III fractures. Because of the high per minute cost of the operating room, surgeon variability significantly impacts cost. Identification and modification of sources of variation in surgeon behavior will allow for reduction in the cost of surgical care. [Orthopedics. 2019; 42(3):e317-e321.].

How Often Do You Lengthen? A Physician Survey on Lengthening Practice for Prosthetic Rib Devices

STUDY DESIGN

Physician survey.

OBJECTIVES

To identify physician practice patterns in use of prosthetic rib devices.

BACKGROUND

Management of scoliosis with prosthetic ribs involves repeated expansions. Despite this, there is a paucity of literature on expansion practice. We believe that despite minimal literature, there exist surgeon practice patterns.

METHODS

Thirty-seven surgeons from the Children's Spine Study Group, with prosthetic rib experience, were anonymously surveyed about their expansion practice.

RESULTS

There was strong consensus that elapsed time since previous surgery was the most important factor in choosing lengthening intervals, with 94.5% of responders agreeing. Surgeons indicated that they often apply a standard expansion interval. 97.3% reported using one in >25% of cases, with 70.3% using a standard interval in >80% of cases. Six months was the most commonly reported elapsed time interval, with 78.4% of responders in agreement. There was also consensus on non-time factors. Patient maturity was cited a major factor in choosing lengthening interval in >80% of cases by 59.5% of responders. Patient age was frequently cited as a factor, with 73% of surgeons using it in >25% of cases. Additionally, there was consensus on factors that were not utilized. More than three-fourths (75.7%) stated that they use patients' bone quality <25% of the time. Similarly, 70.3% used resistance encountered in the last lengthening <25% of the time, with 13.5% never considering.

CONCLUSION

Despite the lack of evidence-based guidelines regarding lengthening practice for prosthetic ribs, there is some consensus on the factors used to choose an appropriate expansion interval. The greatest consensus surrounded the use of a standard six-month elapsed time interval between expansions. From these data, we conclude that specialists have reached relative consensus on factors important for choosing an appropriate expansion interval. We believe these data are an important step toward developing best practice guidelines and identifying areas of equipoise amenable for future research.

LEVEL OF EVIDENCE

Level V.

Use of Continuous Passive Motion Reduces Rates of Arthrofibrosis After Anterior Cruciate Ligament Reconstruction in a Pediatric Population

Joint immobilization after anterior cruciate ligament (ACL) reconstruction may lead to intra-articular adhesions and range of motion deficits. Some practitioners thus advocate for the use of postoperative continuous passive motion (CPM) machine protocols. However, previous studies have failed to show CPM to be effective in increasing postoperative range of motion. Continuous passive motion has, however, been shown to reduce rates of arthrofibrosis requiring manipulation under anesthesia (MUA) in adult populations. To date, there has been no study of the efficacy of CPM after ACL reconstruction in a pediatric population. This was a retrospective cohort study of pediatric patients (age <20 years) who underwent primary ACL reconstruction at an urban tertiary care children's hospital. Clinically significant arthrofibrosis was defined as reduced knee flexion requiring MUA within 6 months of surgery. The final dataset included 163 patients. There was no significant difference between cohorts in range of motion at the 1-week, 1-month, 3-month, and 6-month time points (P=.137, .695, .897, and .339, respectively). The 2 cohorts also did not differ significantly in pain scores at these time points (P=.684, .623, .507, and 1.000, respectively). At 3 and 6 months, neither quadriceps nor hamstrings strength differed significantly between cohorts. Four patients (7.4%) in the no-CPM cohort required MUA for arthrofibrosis within 6 months of surgery, while no patients in the CPM cohort required MUA (P=.023). This suggests that CPM use reduces arthrofibrosis requiring MUA in pediatric patients after ACL reconstruction. Future work may better define the clinical utility and cost-effectiveness of CPM in rehabilitation after these surgeries. [Orthopedics. 2019; 42(1):e81-e85.].

A Dedicated Pediatric Spine Deformity Team Significantly Reduces Surgical Time and Cost

BACKGROUND

As high-quality health care becomes increasingly expensive, improvement projects are focused on reducing cost and increasing value. To increase value by reducing operating room (OR) utilization, we studied the effect of a dedicated team approach for posterior spinal fusion (PSF) for scoliosis.

METHODS

With institutional support, an interdisciplinary, dedicated team was assembled. Members developed standardized protocols for anesthetic management and patient transport, positioning, preparation, draping, imaging, and wake-up. These protocols were initially implemented with a small interdisciplinary team, including 1 surgeon (Phase 1), and then were expanded to include a second surgeon and additional anesthesiology staff (Phase 2). We compared procedures performed with a dedicated team (the Dedicated Team cases) and procedures performed without a such a team (the Casual Team cases). Because of the heterogeneous nature of PSF for scoliosis, we developed a case categorization system: Category 1 was relatively homogeneous and indicated patients with fusion of ≤12 levels, no osteotomies, and a body mass index (BMI) of <25 kg/m, and Category 2 was more heterogeneous and indicated patients with fusion of >12 levels and/or ≥1 osteotomy and/or a BMI of ≥25 kg/m.

RESULTS

In total, 89 Casual Team and 78 Dedicated Team cases were evaluated: 71 were in Category 1 and 96 were in Category 2. Dedicated Team cases used significantly less OR time for both Categories 1 and 2 (p < 0.001). In Category-1 cases, the average reduction was 111.4 minutes (29.7%); in Category-2 cases, it was 76.9 minutes (18.5%). The effect of the Dedicated Team was scalable: the reduction in OR time was significant in both Phase 1 and Phase 2 (p < 0.001). The Dedicated Team cases had no complications. Cost reduction averaged approximately $8,900 for Category-1 and $6,000 for Category-2 cases.

CONCLUSIONS

By creating a dedicated team and standardizing several aspects of PSFs for scoliosis, we achieved a large reduction in OR time. This increase in team efficiency was significant, consistent, and scalable. As a result, we can routinely complete 2 Category-1 PSFs in the same OR with the same team without exceeding standard block time.

Sensitivity to self-administered cocaine within the lateral preoptic-rostral lateral hypothalamic continuum

The lateral preoptic-rostral lateral hypothalamic continuum (LPH) receives projections from the nucleus accumbens and is believed to be one route by which nucleus accumbens signaling affects motivated behaviors. While accumbens firing patterns are known to be modulated by fluctuating levels of cocaine, studies of the LPH's drug-related firing are absent from the literature. The present study sought to electrophysiologically test whether drug-related tonic and slow-phasic patterns exist in the firing of LPH neurons during a free-access cocaine self-administration task. Results demonstrated that a majority of neurons in the LPH exhibited changes in both tonic and slow-phasic firing rates during fluctuating drug levels. During the maintenance phase of self-administration, 69.6% of neurons exhibited at least a twofold change in tonic firing rate when compared to their pre-drug firing rates. Moreover, 54.4% of LPH neurons demonstrated slow-phasic patterns, specifically "progressive reversal" patterns, which have been shown to be related to pharmacological changes across the inter-infusion interval. Firing rate was correlated with calculated drug level in 58.7% of recorded cells. Typically, a negative correlation between drug level and firing rate was observed, with a majority of neurons showing decreases in firing during cocaine self-administration. A small percentage of LPH neurons also exhibited correlations between locomotor behavior and firing rate; however, correlations with drug level in these same neurons were always stronger. Thus, the weak relationships between LPH firing and locomotor behaviors during cocaine self-administration do not account for the observed changes in firing. Overall, these findings suggest that a proportion of LPH neurons are sensitive to fluctuations in cocaine concentration and may contribute to neural activity that controls drug taking.

Differential roles of ventral pallidum subregions during cocaine self-administration behaviors

The ventral pallidum (VP) is necessary for drug-seeking behavior. VP contains ventromedial (VPvm) and dorsolateral (VPdl) subregions, which receive projections from the nucleus accumbens shell and core, respectively. To date no study has investigated the behavioral functions of the VPdl and VPvm subregions. To address this issue, we investigated whether changes in firing rate (FR) differed between VP subregions during four events: approaching toward, responding on, or retreating away from a cocaine-reinforced operandum and a cocaine-associated cue. Baseline FR and waveform characteristics did not differ between subregions. VPdl neurons exhibited a greater change in FR compared with VPvm neurons during approaches toward, as well as responses on, the cocaine-reinforced operandum. VPdl neurons were more likely to exhibit a similar change in FR (direction and magnitude) during approach and response than VPvm neurons. In contrast, VPvm firing patterns were heterogeneous, changing FRs during approach or response alone, or both. VP neurons did not discriminate cued behaviors from uncued behaviors. No differences were found between subregions during the retreat, and no VP neurons exhibited patterned changes in FR in response to the cocaine-associated cue. The stronger, sustained FR changes of VPdl neurons during approach and response may implicate VPdl in the processing of drug-seeking and drug-taking behavior via projections to subthalamic nucleus and substantia nigra pars reticulata. In contrast, the heterogeneous firing patterns of VPvm neurons may implicate VPvm in facilitating mesocortical structures with information related to the sequence of behaviors predicting cocaine self-infusions via projections to mediodorsal thalamus and ventral tegmental area.