Radiographic Union Assessment in Surgically Treated Distal Femur Fractures: A Systematic Review

BACKGROUND

Distal femur fractures are known to have challenging nonunion rates. Despite various available treatment methods aimed to improve union, optimal interventions are yet to be determined. Importantly, there remains no standard agreement on what defines radiographic union. Although various proposed criteria of defining radiographic union exist in the literature, there is no clear consensus on which criteria provide the most precise measurement. The use of inconsistent measures of fracture healing between studies can be problematic and limits their generalizability. Therefore, this systematic review aims to identify how fracture union is defined based on radiographic parameters for surgically treated distal femur fractures in current literature.

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Medline, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science Core Collection databases were searched from inception to October 2022. Studies that addressed surgically treated distal femur fractures with reported radiographic union assessment were included. Outcomes extracted included radiographic definition of union; any testing of validity, reliability, or responsiveness; reported union rate; reported time to fracture union; and any functional outcomes correlated with radiographic union.

RESULTS

Sixty articles with 3,050 operatively treated distal femur fractures were included. Operative interventions included lateral locked plate (42 studies), intramedullary nail (15 studies), dynamic condylar screw or blade plate (7 studies), dual plate or plate and nail construct (5 studies), distal anterior-posterior/posterior-anterior screws (1 study), and external fixation with a circular frame (1 study). The range of mean follow-up time reported was 4.3 to 44 months. The most common definitions of fracture union included "bridging or callus formation across 3 of 4 cortices" in 26 (43%) studies, "bony bridging of cortices" in 21 (35%) studies, and "complete bridging of cortices" in 9 (15%) studies. Two studies included additional assessment of radiographic union using the Radiographic Union Scale in Tibial fracture (RUST) or modified Radiographic Union Scale in Tibial fracture (mRUST) scores. One study included description of validity, and the other study included reliability testing. The reported mean union rate of distal femur fractures was 89% (range 58%-100%). The mean time to fracture union was documented in 49 studies and found to be 18 weeks (range 12-36 weeks) in 2,441 cases. No studies reported correlations between functional outcomes and radiographic parameters.

CONCLUSION

The current literature evaluating surgically treated distal femur fractures lacks consistent definition of radiographic fracture union, and the appropriate time point to make this judgement is unclear. To advance surgical optimization, it is necessary that future research uses validated, reliable, and continuous measures of radiographic bone healing and correlation with functional outcomes.

LEVEL OF EVIDENCE

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

Evaluation of the trajectory of recovery following surgically treated acetabular fractures

Aims

Acetabular fractures are associated with long-term morbidity. Our prospective cohort study sought to understand the recovery trajectory of this injury over five years.

Methods

Eligible patients at a level I trauma centre were recruited into a longitudinal registry of surgical acetabular fractures between June 2004 and August 2019. Patient-reported outcome measures (PROMs), including the 36-Item Short Form Health Survey (SF-36) physical component summary (PCS), were recorded at baseline pre-injury recall and six months, one year, two years, and five years postoperatively. Comparative analyses were performed for elementary and associated fracture patterns. The proportion of patients achieving minimal clinically important difference (MCID) was determined. The rate of, and time to, conversion to total hip arthroplasty (THA) was also established.

Results

We recruited 251 patients (253 fractures), with a 4:1 male to female ratio and mean age of 46.1 years (SD 16.4). Associated fracture patterns accounted for 56.5% of fractures (n = 143). Trajectory analysis showed all timepoints had significant disability versus baseline, including final follow-up (p < 0.001). Elementary fractures had higher SF-36 PCS at six months (p = 0.023) and one year (p = 0.007) compared to associated fractures, but not at two years (p = 0.135) or five years (p = 0.631). The MCID in SF-36 PCS was observed in 37.3% of patients (69/185) between six months and one year, 26.9% of patients (39/145) between one and two years, and 23.3% of patients (20/86) between two and five years, highlighting the long recovery potential of these injuries. A significant proportion of patients failed to attain the MCID after five years (38.1%; 40/105). Conversion to THA occurred in 13.1% of patients (11/110 elementary and 22/143 associated fractures). Approximately two-thirds of THAs (21/33 patients; 63.6%) were performed within two years of index surgery.

Conclusion

Acetabular fractures significantly impact physical function. Recovery trajectory is often elongated beyond one year, with two-thirds of our patients displaying persistent clinically relevant long-term disability.

Effect of humeral rotation on the reliability of radiographic measurements for proximal humerus fractures

BACKGROUND

There are concerns as to the reliability of proximal humerus radiographic measurements, particularly regarding the rotational position of the humerus when obtaining radiographs.

METHODS

Twenty-four patients with proximal humerus fractures fixed surgically with locked plates received postoperative anteroposterior radiographs with the humerus in neutral rotation and in 30° of internal and external rotation. Radiographic measurements for head shaft angle, humeral offset and humeral head height were performed in each humeral rotation position. Intra-class correlation coefficient was used to assess inter-rater and intra-rater reliability. Mean differences (md) in measurements between humeral positions was evaluated using one-way ANOVA.

RESULTS

Head shaft angle demonstrated good-to-excellent reliability; the highest estimates for inter-rater reliability (ICC: 0.85; 95% CI: 0.76, 0.94) and intra-rater reliability (ICC: 0.96; 95% CI: 0.93, 0.98) were achieved in neutral rotation. There were significant differences in measurement values between each rotational position, with mean head shaft angle of 133.1° in external rotation, and increasingly valgus measurements in neutral (md: 7.6°; 95% CI: 5.0, 10.3°; p < 0.001) and internal rotation (md: 26.4°; 95% CI: 21.8, 30.9°; p < 0.001). Humeral head height and humeral offset showed good-to-excellent reliability in neutral and external rotation, but poor inter-rater reliability in internal rotation. Humeral head height was significantly greater using internal compared to external rotation (md: 4.5 mm; 95% CI: 1.7, 7.3 mm; p = 0.002). Humeral offset was significantly greater in external compared to internal rotation (md: 4.6 mm; 95% CI: 2.6, 6.6 mm; p < 0.001).

CONCLUSIONS

Views of the humerus in neutral rotation and 30° of external rotation displayed superior reliability. Differences in radiographic measurement values, depending on humeral rotation views, can make for problematic correlations with patient outcome measures. Studies assessing radiographic outcomes following proximal humerus fractures should ensure standardized humeral rotation for obtaining anteroposterior shoulder radiographs, with neutral rotation and external rotation views likely yielding the most reliable results.

LEVEL OF EVIDENCE

Level IV.

If at first you don't succeed, should you try again? The efficacy of repeated closed reductions of distal radius fractures

INTRODUCTION

A repeated closed reduction ("re-reduction") of a displaced distal radius fracture is a common procedure performed to obtain satisfactory alignment and avoid surgery when the initial reduction is deemed unsatisfactory. However, the efficacy of re-reduction is unclear. Compared to a single closed reduction, does a re-reduction of a displaced distal radius fracture: (1) improve radiographic alignment at the time of fracture union and, (2) decrease the rate of operative intervention?

MATERIALS AND METHODS

Retrospective cohort analysis of 99 adults aged 20-99 years with extra-articular or minimally displaced intra-articular, dorsally angulated, displaced distal radius fracture with or without an associated ulnar styloid fracture who underwent a re-reduction, compared against 99 adults matched for age and sex who were managed with a single reduction. Exclusion criteria were skeletal immaturity, fracture-dislocation and articular displacement greater than 2 mm. Outcome measures included radiographic alignment at fracture union and rate of surgical intervention.

RESULTS

At 6-8 weeks follow-up, the single reduction group had greater radial height (p = 0.045, CI 0.04 to 3.57), and less ulnar variance (p < 0.001, CI - 3.08 to - 1.00) compared to the re-reduction group. Immediately following re-reduction, 49.5% of patients met radiographic non-operative criteria, but by 6-8 weeks follow-up, only 17.5% of patients continued to meet these criteria. Patients in the re-reduction group were treated with surgery 34.3% of the time, compared to 14.1% of the time for patients in the single reduction group (p = 0.001). In patients aged under 65 years, 49.0% of those who underwent a re-reduction were managed with surgery, compared to 21.0% of those who had a single reduction (p = 0.004).

CONCLUSION

A re-reduction performed to improve radiographic alignment and avoid surgical management in this subset of distal radius fractures had minimal value. Alternative treatment options should be considered before attempting a re-reduction.

Assessing the Change in Operative Treatment Rates for Acute Midshaft Clavicle Fractures: Incorporation of Evidence-Based Surgery Results in Orthopaedic Practice

In 2007, a randomized controlled trial (RCT) by the Canadian Orthopaedic Trauma Society (COTS) demonstrated better functional outcomes and a lower proportion of patients who developed malunion or nonunion following operative, compared with nonoperative, treatment of midshaft clavicle fractures. The primary aim of the present study was to compare the proportion of midshaft clavicle fractures treated operatively prior to and following the publication of the COTS RCT. An additional exploratory aim was to assess whether the proportion of midshaft clavicle fractures that were treated with surgery for malunion or nonunion decreased.

Methods

This retrospective cohort analysis used population-level administrative health data on the residents of British Columbia, Canada. Cases were identified by International Classification of Diseases, Ninth Revision (ICD-9) diagnostic codes and procedure fee codes. Adult patients (≥18 years) with closed middle-third clavicle fractures between 1997 and 2018 were included. Multivariable logistic regression modeling compared the proportion of clavicle fractures treated operatively before and after January 1, 2007, controlling for patient factors. The Pearson chi-square test compared the proportion of fractures treated operatively for malunion or nonunion in the cohorts.

Results

A total of 52,916 patients were included (mean age, 47.5 years; 65.6% male). More clavicle fractures were treated operatively from 2007 onward: 6.9% compared with 2.2% prior to 2007 (odds ratio [OR] = 3.35, 95% confidence interval [CI] = 3.03 to 3.70, p < 0.001). Male sex, moderate-to-high income, and younger age were associated with a greater proportion of operative fixation. The rate of surgery for clavicle malunion or nonunion also increased over this time period (to 4.1% from 3.4%, OR = 1.26, 95% CI = 1.15 to 1.38, p < 0.001).

Conclusions

We found a significant change in surgeon practice regarding operative management of clavicle fractures following the publication of a Level-I RCT. With limited high-quality trials comparing operative and nonoperative management, it is important that clinicians, health-care institutions, and health-authority administrations determine what steps can be taken to increase responsiveness to new clinical studies and evidence-based guidelines.

Level of Evidence

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

Beneficial Effects of Preoperative Exercise on the Outcomes of Lumbar Fusion Spinal Surgery

Purpose: To determine whether there was an association between self-reported preoperative exercise and postoperative outcomes after lumbar fusion spinal surgery. Method: We performed a retrospective multivariable analysis of the prospective Canadian Spine Outcomes and Research Network (CSORN) database of 2,203 patients who had elective single-level lumbar fusion spinal surgeries. We compared adverse events and hospital length of stay between patients who reported regular exercise (twice or more per week) prior to surgery ("Regular Exercise") to those exercising infrequently (once or less per week) ("Infrequent Exercise") or those who did no exercise ("No Exercise"). For all final analyses, we compared the Regular Exercise group to the combined Infrequent Exercise or No Exercise group. Results: After making adjustments for known confounding factors, we demonstrated that patients in the Regular Exercise group had fewer adverse events (adjusted odds ratio 0.72; 95% CI: 0.57, 0.91; p = 0.006) and significantly shorter lengths of stay (adjusted mean 2.2 vs. 2.5 d, p = 0.029) than the combined Infrequent Exercise or No Exercise group. Conclusions: Patients who exercised regularly twice or more per week prior to surgery had fewer postoperative adverse events and significantly shorter hospital lengths of stay compared to patients that exercised infrequently or did no exercise. Further study is required to determine effectiveness of a targeted prehabilitation programme.

Fragility Fractures of the Pelvis: Current Practices and Future Directions

PURPOSE OF REVIEW

To summarise the current evidence and clinical practices for patients with fragility fractures of the pelvis (FFP).

RECENT FINDINGS

FFPs are an increasingly prevalent and recognised problem in the elderly population. Recent evidence indicates they have a significant impact on function, morbidity and mortality. While traditional management of FFPs was predominantly non-surgical, surgical options have been increasingly used, with a range of surgical methods available. To date, limited consensus exists on the optimal strategy for suitable patient selection, and clinical trials in this population have proved problematic. The management of FFPs requires a multi-faceted approach to enhance patient care, including adequate pain control, minimisation of complications and optimisation of medical management. Early return to mobilisation should be a key treatment goal to maintain functional independence. The selection of patients who will maximally benefit from surgical treatment, and the most appropriate surgical strategy to employ, remains contentious.

Long-Term Trajectory of Recovery Following Pilon Fracture Fixation

OBJECTIVES

To describe the trajectory of recovery following fixation of pilon fractures from baseline to 5-year follow-up.

DESIGN

Prospective cohort study.

SETTING

Level-1 trauma center.

PATIENTS/PARTICIPANTS

Patients with pilon fractures (OTA/AO 43.C) treated with open reduction and internal fixation.

INTERVENTION

None.

MAIN OUTCOMES MEASURES

Patient-reported outcome measures were measured at baseline, 6 months, 1 year, and 5 years using the Short-Form 36 Health Survey (SF-36) Physical Component Score and Mental Component Score, Short Musculoskeletal Functional Assessment, and the Foot and Ankle Outcome Score.

RESULTS

One hundred two patients were enrolled: mean age was 42.6 years; 69% were males; 88% had an injury severity score of 9; 74 patients (73%) completed 1-year follow-up; 40 patients (39%) completed 5-year follow-up. Trajectory of recovery of physical function showed a significant decline between baseline and 6 months, with significant improvement between 6 months and 1 year and then ongoing but slower improvement between 1 year and 5 years. Sixty-four patients returned to baseline SF-36 Physical Component Score at 5 years. Pain was a persistent issue and remained significantly worse at 5 years when compared with baseline. Psychological well-being (SF-36 Mental Component Score) did not significantly change from baseline at 5 years.

CONCLUSION

Functional recovery following open reduction and internal fixation for pilon fractures was characterized by an initial decrease in function from baseline, followed by an increase between 6 months and 1 year, and then slower but continued increases from 1 year to 5 years. Function did not return to baseline levels, pain was a persistent issue, and mental well-being showed no change from baseline at 5 years. This information may be useful when counselling patients.

LEVEL OF EVIDENCE

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

Responsiveness of the PROMIS physical function measure in orthopaedic trauma patients

OBJECTIVES

To compare the responsiveness of the Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF) to the 36-Item Short Form Survey Physical Component Score (SF36-PCS) in orthopaedic trauma patients from pre-injury to one year recovery.

DESIGN AND SETTING

Prospective cohort study at a Level 1 trauma centre.

PARTICIPANTS

Patients over the age of 18 with orthopaedic trauma injuries to the pelvis, lower extremity or upper extremity between 2017 and 2018.

MAIN OUTCOMES MEASUREMENTS

The PROMIS-PF and SF36-PCS assessments were conducted at baseline, 3 months, 6 months and 12 months. Responsiveness of each measure was assessed between time points by calculating the standardized response mean (SRM), the proportions of patients exceeding minimal clinically important difference (MCID), and the floor and ceiling effects.

RESULTS

Sixty-eight patients with completed assessments at every timepoint were included: mean age 44.7 years, 39 were male and mean Injury Severity Score (ISS) was 7.4 (range: 4-16). Mean time of completion for the SF-36 at all the time points was 5.6 min vs 1.7 min for the PROMIS-PF (p<0.01). The SRM was comparable between measures at all the time points. Although a greater proportion of patients achieved MCID for SF36-PCS between all the time points, this only approached statistical significance between the 6- and 12-month assessments (47.1% vs 33.8%; p = 0.15). There was a significant ceiling effect demonstrated with the PROMIS-PF at baseline and 12-month assessments, with 34 (50.0%) patients and 7 (10.3%) patients achieving the maximum scores at each time point, respectively.

DISCUSSION AND CONCLUSIONS

PROMIS-PF has a more favourable responder burden based on lower time to completion and comparable responsiveness to the SF-36 PCS. However, there are limitations in responsiveness with the PROMIS-PF in patients who are higher functioning as demonstrated by the ceiling effects in patients at baseline pre-injury and at 12 months post-injury timepoints.

Allogeneic blood transfusions and infection risk in lumbar spine surgery: An American College of Surgeons National Surgery Quality Improvement Program Study

BACKGROUND

Allogenic blood transfusions can lead to immunomodulation. Our purpose was to investigate whether perioperative transfusions were associated with postoperative infections and any other adverse events (AEs), after adjusting for potential confounding factors, following common elective lumbar spinal surgery procedures.

STUDY DESIGN AND METHODS

We performed a multivariate, propensity-score matched, regression-adjusted retrospective analysis of the American College of Surgeons National Surgical Quality Improvement Program database between 2012 and 2016. All lumbar spinal surgery procedures were identified (n = 174,891). A transfusion group (perioperative transfusion within 72 h before, during, or after principal surgery; n = 1992) and a control group (no transfusion; n = 1992) were formed. Following adjustment for between-group baseline features, adjusted odds ratios (aOR) and 95% confidence intervals (95% CI) were calculated using a multivariate logistic regression model for any surgical site infection (SSI), superficial SSI, deep SSI, wound dehiscence, pneumonia, urinary tract infection, sepsis, any infection, mortality, and any AEs.

RESULTS

Transfusion was associated with an increased risk of each specific infection, mortality, and any AEs. Statistically significant between-group differences were demonstrated with respect to any SSI (aOR: 1.48; 95% CI: 1.01-2.16), deep SSI (aOR: 1.66; 95% CI: 0.98-2.85), sepsis (aOR: 2.69; 95% CI: 1.43-5.03), wound dehiscence (aOR: 2.27; 95% CI: 0.86-6.01), any infection (aOR: 1.46; 95% CI: 1.13-1.88), any AEs (aOR: 1.80; 95% CI: 1.48-2.18), and mortality (aOR: 2.17; 95% CI: 0.77-6.36).

CONCLUSION

We showed an association between transfusion and infection in lumbar spine surgery after adjustment for various applicable covariates. Sepsis had the highest association with transfusion. Our results reinforce a growing trend toward minimizing perioperative transfusions, which may lead to reduced infections following lumbar spine surgery.

Quantifying Urinary and Sexual Dysfunction After Pelvic Fracture

OBJECTIVES

To quantify the severity of urinary and sexual dysfunction and to evaluate the relationship between urinary and sexual dysfunction, injury, and treatment factors in patients with pelvic fracture.

DESIGN

Prospective cohort study.

SETTING

Level 1 trauma center.

PATIENTS/PARTICIPANTS

One hundred thirteen patients with surgically treated pelvic fracture (65.5% OTA/AO 61B fractures; 7 open fractures; 74 men).

INTERVENTIONS

Surgical pelvic stabilization.

MAIN OUTCOME MEASURES

The 36-Item Short Form Health Survey and International Consultation Incontinence Questionnaire responses were collected at baseline, 6 months, and 1, 2, and 5 years. Patients were scored on symptoms of voiding and incontinence, and filling (for women), to derive urinary function. Sexual function was scored as a single domain. Both genders reported urinary and sexual bothersome symptoms. Regression analysis was used to isolate the importance of predictive factors on urinary and sexual function, urinary and sexual bother, and their impact on quality of life.

RESULTS

Patients with pelvic fracture have significant urinary and sexual dysfunction, which is sustained or worsens over time. Male urinary function was predicted by Injury Severity Score (P = 0.03) and 61C fracture (odds ratio: 3.23, P = 0.04). Female urinary function was predicted by urinary tract injury at admission (odds ratio: 7.57, P = 0.03). Neurologic injury and anterior fixation were identified as significant predictors for male sexual function and sexual bother, whereas urological injuries were important in predicting female urinary and sexual bother (P < 0.01). Sexual function (P = 0.02) and sexual bother (P < 0.001) were important predictors of overall mental well-being in men.

CONCLUSIONS

Urinary and sexual dysfunction are prevalent and sustained in men and women and do not follow the prolonged slow recovery trajectory seen in physical function. Male urinary and sexual dysfunction was closely tied to neurologic injury, whereas female urinary and sexual dysfunction was predicted by the presence of a urinary tract injury. Urinary and sexual dysfunction were important to overall mental well-being in men.

LEVEL OF EVIDENCE

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

Effect of orthopaedic resident education on screening for intimate partner violence

BACKGROUND

Intimate Partner Violence (IPV) is prevalent in women presenting to orthopaedic fracture clinics. Rates of IPV have increased during the COVID-19 global pandemic. Our aim was to determine the effect of educational experiences on IPV knowledge and IPV screening to inform best-practices in resident education.

METHODS

Cross-sectional online survey of orthopaedic surgery residency programs in Canada. Demographics, IPV educational experiences, IPV knowledge, and frequency of IPV screening were collected via a modified version of the Physician Readiness to Manage Intimate Partner Violence Survey (PREMIS). Descriptive statistics and regression modeling identified predictors of IPV knowledge and frequency of IPV screening.

RESULTS

Responses were obtained from 105 orthopaedic residents; 84% participated in classroom training, 39% underwent mentorship training, 32% received both classroom training and mentorship, and 10% reported neither. Classroom training had no statistically significant association with IPV knowledge or frequency of IPV screening. Residents who received mentorship were 4.1 times more likely to screen for IPV (95% CI: 1.72-10.05), older residents were more likely to screen for IPV (OR: 8.3, 95% CI: 2.64-29.84), and senior residents were less likely to screen for IPV than junior residents (OR: 0.29, 95% CI: 0.09-0.82).

CONCLUSIONS

Classroom training was not associated with any effect on IPV knowledge nor the frequency of IPV screening. Educational efforts should be targeted at increasing mentorship opportunities in order to improve IPV screening practices in Canadian orthopaedic residents.

Effect of omega-3 fatty acids supplementation on adipokines: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Although a large body of literature reported the beneficial effects of omega-3 fatty acids (omega-3 FAs) consumption on adipokines levels, but recent findings from clinical trials are not univocal. The aim of this systematic review and meta-analysis was to evaluate the effect of omega-3 FAs supplements on adipokines.

METHODS

We searched Medline, Web of Science, Scopus, Embase, and Cochrane Library from inception to August 2020 without any particular language limitations. Outcomes were summarized as standardized mean difference (SMD) with 95% confidence intervals (CIs) estimated from Hedge's g and random effects modeling.

RESULTS

Fifty-two trials involving 4,568 participants were included. Omega-3 FAs intake was associated with a significant increase in plasma adiponectin levels (n = 43; 3,434 participants; SMD: 0.21, 95% CI: 0.04, 0.37; p = 0.01; I²= 80.14%). This meta-analysis indicates that supplementing participants with omega-3 fatty acids more than 2000 mg daily and more than 10 weeks resulted in a significant and more favorable improvement in plasma adiponectin levels. However, omega-3 FAs intake had no significant effect on leptin levels (SMD: -0.02, 95% CI: -0.20, 0.17, I²= 54.13%).

CONCLUSION

The evidence supports a beneficial effect of omega-3 FAs intake on serum adiponectin levels but does not appear to impact on leptin concentrations. Larger well-designed RCTs are still required to evaluate the effect of omega-3 FAs on leptin in specific diseases.

Capturing adverse events in elective orthopedic surgery: comparison of administrative, surgeon and reviewer reporting

Summary

Ensuring adverse event (AE) recording is standardized and accurate is paramount for patient safety. In this discussion, we outline our comparison of AE data collected by orthopedic surgeons and independent clinical reviewers using the Spine Adverse Events Severity System (SAVES) and Orthopedic Surgical Adverse Events Severity System (OrthoSAVES) against AE data recorded by hospital administrative discharge abstract coders. In 164 spine, hip, knee and shoulder patients, reviewers recorded significantly more AEs than coders, and coders recorded significantly more AEs than surgeons. The AEs were recorded similarly by reviewers using SAVES and OrthoSAVES in 48 spine patients. Despite our small sample size and use of different AE tools, we believe it is important to highlight that coders, surgeons and reviewers recorded AEs differently. While further investigations on its utility and cost-effectiveness are necessary, we assert that it is feasible to use Ortho-SAVES to prospectively record AEs across all orthopedic subspecialties.

Management of cervical spine epidural abscess: a systematic review

Background:

Cervical spinal epidural abscess (CSEA) is a localized infection between the thecal sac and cervical spinal column which may result in neurological deficit and death if inadequately treated. Two treatment options exist: medical management and surgical intervention. Our objective was to analyze CSEA patient outcomes in order to determine the optimal method of treatment.

Methods:

An electronic literature search for relevant case series and retrospective reviews was conducted through June 2016. Data abstraction and study quality assessment were performed by two independent reviewers. A lack of available data led to a post hoc decision not to perform meta-analysis of the results; study findings were synthesized qualitatively.

Results:

927 studies were identified, of which 11 were included. Four studies were ranked as good quality, and seven ranked as fair quality. In total, data from 173 patients were included. Mean age was 55 years; 61.3% were male. Intravenous drug use was the most common risk factor for CSEA development. Staphylococcus aureus was the most commonly cultured pathogen. 140 patients underwent initial surgery, an additional 18 patients were surgically treated upon failure of medical management, and 15 patients were treated with antibiotics alone.

Conclusion:

The rates of medical management failure described in our review were much higher than those reported in the literature for thoracolumbar spinal epidural abscess patients, suggesting that CSEA patients may be at a greater risk for poor outcomes following nonoperative treatment. Thus, early surgery appears most viable for optimizing CSEA patient outcomes. Further research is needed in order to corroborate these recommendations.

Highlighting discrepancies in walking prediction accuracy for patients with traumatic spinal cord injury: an evaluation of validated prediction models using a Canadian Multicenter Spinal Cord Injury Registry

BACKGROUND CONTEXT

Models for predicting recovery in traumatic spinal cord injury (tSCI) patients have been developed to optimize care. Several models predicting tSCI recovery have been previously validated, yet recent findings question their accuracy, particularly in patients whose prognoses are the least predictable.

PURPOSE

To compare independent ambulatory outcomes in AIS (ASIA [American Spinal Injury Association] Impairment Scale) A, B, C, and D patients, as well as in AIS B+C and AIS A+D patients by applying two existing logistic regression prediction models.

STUDY DESIGN

A prospective cohort study.

PARTICIPANT SAMPLE

Individuals with tSCI enrolled in the pan-Canadian Rick Hansen SCI Registry (RHSCIR) between 2004 and 2016 with complete neurologic examination and Functional Independence Measure (FIM) outcome data.

OUTCOME MEASURES

The FIM locomotor score was used to assess independent walking ability at 1-year follow-up.

METHODS

Two validated prediction models were evaluated for their ability to predict walking 1-year postinjury. Relative prognostic performance was compared with the area under the receiver operating curve (AUC).

RESULTS

In total, 675 tSCI patients were identified for analysis. In model 1, predictive accuracies for 675 AIS A, B, C, and D patients as measured by AUC were 0.730 (95% confidence interval [CI] 0.622-0.838), 0.691 (0.533-0.849), 0.850 (0.771-0.928), and 0.516 (0.320-0.711), respectively. In 160 AIS B+C patients, model 1 generated an AUC of 0.833 (95% CI 0.771-0.895), whereas model 2 generated an AUC of 0.821 (95% CI 0.754-0.887). The AUC for 515 AIS A+D patients was 0.954 (95% CI 0.933-0.975) with model 1 and 0.950 (0.928-0.971) with model 2. The difference in prediction accuracy between the AIS B+C cohort and the AIS A+D cohort was statistically significant using both models (p=.00034; p=.00038). The models were not statistically different in individual or subgroup analyses.

CONCLUSIONS

Previously tested prediction models demonstrated a lower predictive accuracy for AIS B+C than AIS A+D patients. These models were unable to effectively prognosticate AIS A+D patients separately; a failure that was masked when amalgamating the two patient populations. This suggests that former prediction models achieved strong prognostic accuracy by combining AIS classifications coupled with a disproportionately high proportion of AIS A+D patients.

The Use of a Self-Administered Questionnaire to Reduce Consultation Wait Times for Potential Elective Lumbar Spinal Surgical Candidates: A Prospective, Pragmatic, Blinded, Randomized Controlled Quality Improvement Study

BACKGROUND

In a public health-care system, patients often experience lengthy wait times to see a spine surgeon for consultation, and most patients are found not to be surgical candidates, thereby prolonging the wait time for those who are. The aim of this study was to evaluate whether a self-administered 3-item questionnaire (3IQ) could reprioritize consultation appointments and reduce wait times for lumbar spinal surgical candidates.

METHODS

This prospective, pragmatic, blinded, randomized controlled quality improvement study was conducted at a single Canadian academic health-care center. This study enrolled 227 consecutive eligible participants with an elective lumbar condition who were referred for consultation with a spine surgeon. All participants were mailed the 3IQ after their referral was received. Patients were randomized into the intervention group, in which leg-dominant pain reported on the 3IQ resulted in an upgrade in priority to be seen, or into the control group, in which no change to wait-list priority occurred. The main outcome measured was time to consultation for participants who were deemed surgical candidates following consultation.

RESULTS

There were no significant differences between groups with regard to demographics, overall group wait times, proportion of surgical candidates, or disability. A total of 33 patients were deemed surgical candidates after consultation. The median wait from referral to consultation was shorter for the 16 surgical candidates in the intervention group (2.5 months; interquartile range [IQR]: 2.0 to 4.8 months) compared with the 17 surgical candidates in the control group (4.5 months; IQR: 3.4 to 6.9 months; p = 0.090). The odds of seeing a surgical candidate within the acceptable time frame of 3 months were 5.4 times greater (95% confidence interval: 1.2 to 24.5 times; p = 0.024) in the intervention group.

CONCLUSIONS

The use of a simple, self-administered questionnaire to reprioritize referrals resulted in shorter consultation wait times for patients who required a surgical procedure and significantly increased the number of surgical candidates seen within the acceptable time frame. It may be valuable to consider adding the 3IQ to clinical care practices to better triage these patients on waiting lists.

Increased Prevalence of Chronic Disease in Back Pain Patients Living in Car-dependent Neighbourhoods in Canada: A Cross-sectional Analysis

Objectives

Chronic diseases, including back pain, result in significant patient morbidity and societal burden. Overall improvement in physical fitness is recommended for prevention and treatment. Walking is a convenient modality for achieving initial gains. Our objective was to determine whether neighbourhood walkability, acting as a surrogate measure of physical fitness, was associated with the presence of chronic disease.

Methods

We conducted a cross-sectional study of prospectively collected data from a prior randomized cohort study of 227 patients referred for tertiary assessment of chronic back pain in Ottawa, ON, Canada. The Charlson Comorbidity Index (CCI) was calculated from patient-completed questionnaires and medical record review. Using patients’ postal codes, neighbourhood walkability was determined using the Walk Score, which awards points based on the distance to the closest amenities, yielding a score from 0 to 100 (0-50: car-dependent; 50-100: walkable).

Results

Based on the Walk Score, 134 patients lived in car-dependent neighborhoods and 93 lived in walkable neighborhoods. A multivariate logistic regression model, adjusted for age, gender, rural postal code, body mass index, smoking, median household income, percent employment, pain, and disability, demonstrated an adjusted odds ratio of 2.75 (95% confidence interval, 1.16 to 6.53) times higher prevalence for having a chronic disease for patients living in a car-dependent neighborhood. There was also a significant dose-related association (p=0.01; Mantel-Haenszel chi-square=6.4) between living in car-dependent neighbourhoods and more severe CCI scores.

Conclusions

Our findings suggest that advocating for improved neighbourhood planning to permit greater walkability may help offset the burden of chronic disease.

A comparison of outcomes between Canada and the United States in patients recovering from hip fracture repair: secondary analysis of the FOCUS trial

Objective

To determine if adjusted mortality, walking ability or return home differed after hip fracture surgery between Canada and the USA.

Design

Secondary analysis of the Functional Outcomes in Cardiovascular Patients Undergoing Surgical Hip Fracture Repair (FOCUS) trial data.

Setting

Data were collected from 47 American and Canadian hospitals.

Participants

Overall, 2016 subjects with a hip fracture (USA = 1222 (60.6%); Canada = 794 (39.4%)) were randomized to a liberal or restrictive transfusion strategy. Subjects were 50 years and older, with cardiovascular disease and/or risk factors and hemoglobin <100 g/L within 3 days post-surgery. The average age was 82 years and 1527(76%) subjects were females.

Intervention

Demographics, health status and health services data were collected up to 60 days post-surgery and mortality to a median of 3 years post-surgery.

Main outcomes

Mortality, inability to walk and return home.

Results

US subjects had higher adjusted mortality than Canadians at 30 days (odds ratio = 1.78; 95% confidence interval: 1.09-2.90), 60 days (1.53; 1.02-2.29) and up to 3 years (hazard ratio = 1.25; 1.07-1.45). There were no differences in adjusted outcomes for walking ability or return home at 30 or 60 days post-surgery. Median hospital length of stay was longer (P < 0.0001) in Canada (9 days; interquartile range: 5-18 days) than the US (3 days; 2-5 days). US subjects (52.9%) were more likely than Canadians (16.8%) to be discharged to nursing homes for rehabilitation (P < 0.001).

Conclusions

Adjusted survival favored Canadians post hip fracture while walking ability and return home were not different between countries. The reason(s) for mortality differences warrant further investigation.

Activities performed and treatments conducted before consultation with a spine surgeon: are patients and clinicians following evidence-based clinical practice guidelines?

BACKGROUND CONTEXT

Clinical practice guidelines (CPGs) are designed to ensure that evidence-based treatment is easily put into action. Whether patients and clinicians follow these guidelines is equivocal.

PURPOSE

The objectives of this study were to examine how many patients complaining of low back pain (LBP) underwent evidence-based medical interventional treatment in line with CPG recommendations before consultation with a spine surgeon, and to evaluate any associations between adherence to CPG recommendations and baseline factors.

STUDY DESIGN/SETTING

This is a cross-sectional cohort analysis at a tertiary care center.

PATIENT SAMPLE

A total of 229 patients were referred for surgical consultation for an elective lumbar spinal condition.

OUTCOME MEASURES

The outcome measures include the number of CPG-recommended treatments undertaken by patients at or before the time of referral, the validated pain score, the EuroQol-5D (EQ-5D) health status, and the Oswestry Disability Index (ODI) score.

METHODS

Questionnaires assessing demographic and functional characteristics as well as overall health care use were sent to patients immediately after their referral was received by the surgeon's office.

RESULTS

Medications were the most common modality before consultation (74.2% of patients), of which 46.3% received opioids. The number of medications taken was significantly related to a higher ODI score (R=0.23, p=.0004), a higher pain score (R=0.15, p=.026), and a lower EQ-5D health status (R=-0.15, p=.024). In contrast, a lower pain score (7.2 vs. 7.7, p=.037) and a lower ODI score (26.6 vs. 29.9, p=.0023) were associated with performing adequate amounts of exercise. There was a significant association between lower numbers of treatments received and higher numerical pain rating scores (R=-0.14, p=.035). The majority (61.1%) of patients received two or less forms of treatment.

CONCLUSIONS

Evidence-based medical interventional treatments for patients with LBP are not being taken advantage of before spine surgery consultation. If more patients were to undertake CPG-endorsed conservative modalities, it may result in fewer unnecessary referrals from primary care physicians, and patients might not deteriorate as much while lingering on long wait lists. Further studies incorporating knowledge translation or health system pathway changes are necessary.

A simplified clinical prediction rule for prognosticating independent walking after spinal cord injury: a prospective study from a Canadian multicenter spinal cord injury registry

BACKGROUND CONTEXT

Traumatic spinal cord injury (SCI) is a debilitating condition with limited treatment options for neurologic or functional recovery. The ability to predict the prognosis of walking post injury with emerging prediction models could aid in rehabilitation strategies and reintegration into the community.

PURPOSE

To revalidate an existing clinical prediction model for independent ambulation (van Middendorp et al., 2011) using acute and long-term post-injury follow-up data, and to investigatethe accuracy of a simplified model using prospectively collected data from a Canadian multicenter SCI database, the Rick Hansen Spinal Cord Injury Registry (RHSCIR).

STUDY DESIGN

Prospective cohort study.

PARTICIPANT SAMPLE

The analysis cohort consisted of 278 adult individuals with traumatic SCI enrolled in the RHSCIR for whom complete neurologic examination data and Functional Independence Measure (FIM) outcome data were available.

OUTCOME MEASURES

The FIM locomotor score was used to assess independent walking ability (defined as modified or complete independence in walk or combined walk and wheelchair modality) at 1-year follow-up for each participant.

METHODS

A logistic regression (LR) model based on age and four neurologic variables was applied to our cohort of 278 RHSCIR participants. Additionally, a simplified LR model was created. The Hosmer-Lemeshow goodness of fit test was used to check if the predictive model is applicable to our data set. The performance of the model was verified by calculating the area under the receiver operating characteristic curve (AUC). The accuracy of the model was tested using a cross-validation technique. This study was supported by a grant from The Ottawa Hospital Academic Medical Organization ($50,000 over 2 years). The RHSCIR is sponsored by the Rick Hansen Institute and is supported by funding from Health Canada, Western Economic Diversification Canada, and the provincial governments of Alberta, British Columbia, Manitoba, and Ontario. ET and JP report receiving grants from the Rick Hansen Institute (approximately $60,000 and $30,000 per year, respectively). DMR reports receiving remuneration for consulting services provided to Palladian Health, LLC and Pacira Pharmaceuticals, Inc ($20,000-$30,000 annually), although neither relationship presents a potential conflict of interest with the submitted work. KEH received a grant for involvement in the present study from the Government of Canada as part of the Canada Summer Jobs Program ($3,000). JP reports receiving an educational grant from Medtronic Canada outside of the submitted work ($75,000 annually). TM reports receiving educational fellowship support from AO Spine, AO Trauma, and Medtronic; however, none of these relationships are financial in nature. All remaining authors have no conflicts of interest to disclose.

RESULTS

The fitted prediction model generated 85% overall classification accuracy, 79% sensitivity, and 90% specificity. The prediction model was able to accurately classify independent walking ability (AUC 0.889, 95% confidence interval [CI] 0.846-0.933, p<.001) compared with the existing prediction model, despite the use of a different outcome measure (FIM vs. Spinal Cord Independence Measure) to qualify walking ability. A simplified, three-variable LR model based on age and two neurologic variables had an overall classification accuracy of 84%, with 76% sensitivity and 90% specificity, demonstrating comparable accuracy with its five-variable prediction model counterpart. The AUC was 0.866 (95% CI 0.816-0.916, p<.01), only marginally less than that of the existing prediction model.

CONCLUSIONS

A simplified predictive model with similar accuracy to a more complex model for predicting independent walking was created, which improves utility in a clinical setting. Such models will allow clinicians to better predict the prognosis of ambulation in individuals who have sustained a traumatic SCI.

Continuous Quality Improvement in Orthopaedic Surgery: Improving Patient Experience, Safety and Outcomes

As the demand for accountability and transparency surrounding the supply of increasingly expensive medical services grows, health- care providers have put continuous quality improvement (CQI) programs in place to optimize care and improve efficiencies. CQI pro- grams that rigorously evaluate healthcare services can lead to informed decisions about the direction of planned improvements through evolving knowledge translation. Successful end products may include better patient satisfaction, improved patient-reported outcomes, highly-efficient care pathways, and overall cost-savings. There are numerous steps involved in implementing CQI programs that require collaboration and cooperation from physicians, allied health care workers, support staff and hospital management in order to achieve desirable goals. The Division of Orthopaedic Surgery at The Ottawa Hospital (TOH) has initiated a CQI program which is designed as a classic Donabedian Construct with a triple aim framework of: 1. improving care, 2. improving patient experience, and 3. lowering cost. The development of our electronic CQI database will be a key component in the 5-year (2015-2020) Strategic Plan for the Division, and is in keeping with the goal of TOH becoming a top 10% performer in quality and safety of patient care in North America. The aim of this paper is to outline our compliance with the ongoing activities required to meet clearly delineated quality metrics, and the development of the many facets of our CQI program. RÉSUMÉ En réponse à la demande croissante de transparence et de responsabilité concernant les services de santé dispendieux, les fournis- seurs de soins de santé ont mis sur pied des programmes d’amélioration continue de la qualité (ACQ) pour optimiser les soins et l’efficience. Les programmes d’ACQ qui évaluent rigoureusement les services de santé permettent des décisions plus éclairées quant aux améliorations à apporter, grâce au transfert de connaissances. Parmi les résultats positifs de ces programmes, on peut compter une plus grande satisfaction et une amélioration des résultats rapportés par les patients, des plans d’intervention particulièrement efficients, et une réduction des coûts. De nombreuses étapes dans la mise en place des programmes d’ACQ nécessitent une collabora- tion entre les médecins, le personnel de soutien, les gestionnaires de l’hôpital et les autres professionnels de la santé afin d’atteindre les objectifs désirés. La Division de chirurgie orthopédique de l’Hôpital d’Ottawa a lancé un programme d’ACQ conçu selon le modèle classique Donabedian, qui poursuit un triple objectif : 1. améliorer les soins, 2. améliorer l’expérience des patients, et 3. minimiser les coûts. La création d’une base de données électronique pour l’ACQ sera une composante clé du plan stratégique de 5 ans (2015-2020) de la Division, et se conforme à l’objectif de l’Hôpital d’Ottawa de devenir l’un des plus performants en Amérique du Nord, sur le plan de la qualité et de la sécurité des soins aux patients. Le but de cet article est de décrire brièvement le développement de nombreuses facettes de notre programme d’ACQ, et notre conformité aux normes de la qualité. 

Can Surgeons Adequately Capture Adverse Events Using the Spinal Adverse Events Severity System (SAVES) and OrthoSAVES?

BACKGROUND

Physicians have consistently shown poor adverse-event reporting practices in the literature and yet they have the clinical acumen to properly stratify and appraise these events. The Spine Adverse Events Severity System (SAVES) and Orthopaedic Surgical Adverse Events Severity System (OrthoSAVES) are standardized assessment tools designed to record adverse events in orthopaedic patients. These tools provide a list of prespecified adverse events for users to choose from-an aid that may improve adverse-event reporting by physicians.

QUESTIONS/PURPOSES

The primary objective was to compare surgeons' adverse-event reporting with reporting by independent clinical reviewers using SAVES Version 2 (SAVES V2) and OrthoSAVES in elective orthopaedic procedures.

METHOD

This was a 10-week prospective study where SAVES V2 and OrthoSAVES were used by six orthopaedic surgeons and two independent, non-MD clinical reviewers to record adverse events after all elective procedures to the point of patient discharge. Neither surgeons nor reviewers received specific training on adverse-event reporting. Surgeons were aware of the ongoing study, and reported adverse events based on their clinical interactions with the patients. Reviewers recorded adverse events by reviewing clinical notes by surgeons and other healthcare professionals (such as nurses and physiotherapists). Adverse events were graded using the severity-grading system included in SAVES V2 and OrthoSAVES. At discharge, adverse events recorded by surgeons and reviewers were recorded in our database.

RESULTS

Adverse-event data for 164 patients were collected (48 patients who had spine surgery, 51 who had hip surgery, 34 who had knee surgery, and 31 who had shoulder surgery). Overall, 99 adverse events were captured by the reviewers, compared with 14 captured by the surgeons (p < 0.001). Surgeons adequately captured major adverse events, but failed to record minor events that were captured by the reviewers. A total of 93 of 99 (94%) adverse events reported by reviewers required only simple or minor treatment and had no long-term adverse effect. Three patients experienced adverse events that resulted in use of invasive or complex treatment that had a temporary adverse effect on outcome.

CONCLUSION

Using SAVES V2 and OrthoSAVES, independent reviewers reported more minor adverse events compared with surgeons. The value of third-party reviewers requires further investigation in a detailed cost-benefit analysis.

LEVEL OF EVIDENCE

Level II, therapeutic study.

A systematic review of preoperative predictors for postoperative clinical outcomes following lumbar discectomy

BACKGROUND CONTEXT

Sciatica is often caused by a herniated lumbar intervertebral disc. When conservative treatment fails, a lumbar discectomy can be performed. Surgical treatment via lumbar discectomy is not always successful and may depend on a variety of preoperative factors. It remains unclear which, if any, preoperative factors can predict postsurgical clinical outcomes.

PURPOSE

This review aimed to determine preoperative predictors that are associated with postsurgical clinical outcomes in patients undergoing lumbar discectomy.

STUDY DESIGN

This is a systematic review.

METHODS

This systematic review of the scientific literature followed the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. MEDLINE and PubMed were systematically searched through June 2014. Results were screened for relevance independently, and full-text studies were assessed for eligibility. Reporting quality was assessed using a modified Newcastle-Ottawa Scale. Quality of evidence was assessed using a modified version of Sackett's Criteria of Evidence Support. No financial support was provided for this study. No potential conflict of interest-associated biases were present from any of the authors.

RESULTS

The search strategy yielded 1,147 studies, of which a total of 40 high-quality studies were included. There were 17 positive predictors, 20 negative predictors, 43 non-significant predictors, and 15 conflicting predictors determined. Preoperative predictors associated with positive postoperative outcomes included more severe leg pain, better mental health status, shorter duration of symptoms, and younger age. Preoperative predictors associated with negative postoperative outcomes included intact annulus fibrosus, longer duration of sick leave, worker's compensation, and greater severity of baseline symptoms. Several preoperative factors including motor deficit, side and level of herniation, presence of type 1 Modic changes and degeneration, age, and gender had non-significant associations with postoperative clinical outcomes.

CONCLUSIONS

It may be possible for certain preoperative factors to be targeted for clinical evaluation by spine surgeons to assess the suitability of patients for lumbar discectomy surgery, the hope being to thereby improve postoperative clinical outcomes. Prospective cohort studies are required to increase the level of evidence with regard to significant predictive factors.

Reliability, validity, and responsiveness of the Western Ontario and McMaster Universities Osteoarthritis Index for elderly patients with a femoral neck fracture

BACKGROUND

The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) has been extensively evaluated in groups of patients with osteoarthritis, yet not in patients with a femoral neck fracture. This study aimed to determine the reliability, construct validity, and responsiveness of the WOMAC compared with the Short Form-12 (SF-12) and the EuroQol 5D (EQ-5D) questionnaires for the assessment of elderly patients with a femoral neck fracture.

METHODS

Reliability was tested by assessing the Cronbach alpha. Construct validity was determined with the Pearson correlation coefficient. Change scores were calculated from ten weeks to twelve months of follow-up. Standardized response means and floor and ceiling effects were determined. Analyses were performed to compare the results for patients less than eighty years old with those for patients eighty years of age or older.

RESULTS

The mean WOMAC total score was 89 points before the fracture in the younger patients and increased from 70 points at ten weeks to 81 points at two years postoperatively. In the older age group, these scores were 86, 75, and 78 points. The mean WOMAC pain scores before the fracture and at ten weeks and two years postoperatively were 92, 76, and 87 points, respectively, in the younger age group and 92, 84, and 93 points in the older age group. Function scores were 89, 68, and 79 points for the younger age group and 84, 71, and 73 points for the older age group. The Cronbach alpha for pain, stiffness, function, and the total scale ranged from 0.83 to 0.98 for the younger age group and from 0.79 to 0.97 for the older age group. Construct validity was good, with 82% and 79% of predefined hypotheses confirmed in the younger and older age groups, respectively. Responsiveness was moderate. No floor effects were found. Moderate to large ceiling effects were found for pain and stiffness scales at ten weeks and twelve months in younger patients (18% to 36%) and in the older age group (38% to 53%).

CONCLUSIONS

The WOMAC showed good reliability, construct validity, and responsiveness in both age groups of elderly patients with a femoral neck fracture who had been physically and mentally fit before the fracture. The instrument is suitable for use in future clinical studies in these populations.

CLINICAL RELEVANCE

The results are based on two clinical trials. The questionnaires used concern pure, clinically relevant issues (ability to walk, climb stairs, etc.). Moreover, the results can be used for future research comparing clinical outcomes (or treatments) for populations with a femoral neck fracture.

Stability of postoperative delirium psychomotor subtypes in individuals with hip fracture

OBJECTIVES

To determine the stability of psychomotor subtypes of delirium over time and identify characteristics associated with delirium psychomotor subtypes in individuals undergoing surgical repair of hip fracture.

DESIGN

Prospective cohort study.

SETTING

The Transfusion Trigger Trial for Functional Outcomes in Cardiovascular Patients Undergoing Surgical Hip Fracture Repair Cognitive Ancillary Study was conducted at 13 participating sites from 2008 to 2009.

PARTICIPANTS

Individuals who had undergone surgical repair of hip fracture (N=139).

MEASUREMENTS

Delirium was assessed up to four times postoperatively using the Confusion Assessment Method (CAM) and the Memorial Delirium Assessment Scale. Psychomotor subtypes of delirium were categorized as hypoactive, hyperactive, mixed, and normal psychomotor activity.

RESULTS

Incidence of postoperative delirium was 41% (n=57). Of 90 CAM-positive (CAM+) observations, 56% were hypoactive, 10% were hyperactive, 21% were mixed, and 14% had normal psychomotor symptoms. Of 26 participants with more than one CAM+ assessment, 50% maintained subtype stability over time. Participants with hypoactive or normal psychomotor symptoms (n=31) were less likely to have chart documentation of delirium than participants with any hyperactive symptoms (n=19) (22% vs 58%, P=.009).

CONCLUSION

Psychomotor subtypes of delirium often fluctuate from assessment to assessment, rather than representing fixed categories of delirium. Hypoactive delirium is the most common presentation of delirium but is the least likely to be documented by healthcare providers.

Association of rs11190870 near LBX1 with adolescent idiopathic scoliosis in East Asians: a systematic review and meta-analysis

BACKGROUND CONTEXT

The rs11190870 single nucleotide polymorphism in the 3'-flanking region of the LBX1 gene has been implicated in the etiology of adolescent idiopathic scoliosis (AIS). A thorough appraisal of the evidence supporting this association has not been previously attempted.

PURPOSE

To provide a comprehensive assessment and synthesis of the currently available evidence on the association between rs11190870 and AIS.

STUDY DESIGN

A systematic review and meta-analysis.

METHODS

This review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. PubMed (MEDLINE), EMBASE, Scopus, and HuGE Literature Finder databases were systematically searched through November 2013 to identify relevant studies following a sensitive strategy. Summary odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using the fixed-effect inverse variance model for allelic (T vs. C) and genotypic comparisons.

RESULTS

Meta-analysis of four studies conducted in East Asian populations (n=3,215 AIS cases and n=15,347 controls) found a highly statistically significant and robust association between rs11190870 and AIS. Comparison of summary ORs indicated a codominant model effect of the T allele. Carriers of the TC and TT genotypes were 69% (OR=1.69, 95% CI: 1.48-1.94, p<.001) and 162% (OR=2.62, 95% CI: 2.28-3.02, p<.001), respectively, more likely to have AIS compared with carriers of the CC genotype.

CONCLUSIONS

Based on a comprehensive analysis of the currently available evidence, rs11190870 is likely a susceptibility variant for AIS in East Asians. Further investigation of this association is necessary in other populations.

Delirium outcomes in a randomized trial of blood transfusion thresholds in hospitalized older adults with hip fracture

OBJECTIVES

To determine whether a higher blood transfusion threshold would prevent new or worsening delirium symptoms in the hospital after hip fracture surgery.

DESIGN

Ancillary study to a randomized clinical trial.

SETTING

Thirteen hospitals in the United States and Canada.

PARTICIPANTS

One hundred thirty-nine individuals hospitalized with hip fracture aged 50 and older (mean age 81.5 ± 9.1) with cardiovascular disease or risk factors and hemoglobin concentrations of less than 10 g/dL within 3 days of surgery recruited in an ancillary study of the Transfusion Trigger Trial for Functional Outcomes in Cardiovascular Patients Undergoing Surgical Hip Fracture Repair.

INTERVENTION

Individuals in the liberal treatment group received one unit of packed red blood cells and as much blood as needed to maintain hemoglobin concentrations at greater than 10 g/dL; those in the restrictive treatment group received transfusions if they developed symptoms of anemia or their hemoglobin fell below 8 g/dL.

MEASUREMENTS

Delirium assessments were performed before randomization and up to three times after randomization. The primary outcome was severity of delirium according to the Memorial Delirium Assessment Scale (MDAS). The secondary outcome was the presence or absence of delirium defined according to the Confusion Assessment Method (CAM).

RESULTS

The liberal group received a median two units of blood and the restrictive group zero units of blood. Hemoglobin concentration on Day 1 after randomization was 1.4 g/dL higher in the liberal group. Treatment groups did not differ significantly at any time point or over time on MDAS delirium severity (P = .28) or CAM delirium presence (P = .83).

CONCLUSION

Blood transfusion to maintain hemoglobin concentrations greater than 10 g/dL alone is unlikely to influence delirium severity or rate in individuals with hip fracture after surgery with a hemoglobin concentration less than 10 g/dL.

Delay in operative stabilization of spine fractures in multitrauma patients without neurologic injuries: effects on outcomes

BACKGROUND

Optimal timing for surgical stabilization of the fractured spine is controversial. Early stabilization facilitates mobilization and theoretically reduces associated complications.

METHODS

We identified consecutive patients without neurologic injury requiring stabilization surgery for a spinal fracture at an academic tertiary-care hospital over a 12-year period. Incidences of postoperative complications were prospectively evaluated. We analyzed results based on the time elapsed before the final surgical stabilization procedure. Multivariate analyses were performed to explore the effects of potential confounders.

RESULTS

A total of 83 patients (60 men, 23 women; mean age 39.4 yr) met the eligibility criteria and were enrolled. The mean Injury Severity Score (ISS) was 27.1 (range 12.0-57.0); 35% of patients had a cervical fracture and 65% had a thoraco-lumbar fracture. No statistically significant associations were uncovered between time to surgical stabilization and age, ISS or comorbidities. Comparing patients stabilized after 24 hours with those stabilized within 24 hours, there was an almost 8-fold greater risk of a complication related to prolonged recumbency (p = 0.007). We observed similar effects for other types of complications. Delays of more than 72 hours had a negative effect on complication rates; these effects remained significant after multivariate adjustments for age, comorbidity and ISS.

CONCLUSION

This study demonstrates a strong relation between timing of surgical stabilization of spinal fractures in multitrauma patients without neurologic injuries and complications. Further studies with larger samples may allow for better adjustment of potentially confounding factors and identify subgroups in which this effect is most pronounced.

Pilot evaluation of a multidisciplinary, medically supervised, nonsurgical weight loss program on the severity of low back pain in obese adults

BACKGROUND CONTEXT

Low back pain (LBP) is a prevalent and costly condition. Although its etiology is largely unknown, a link to obesity is suspected, and weight loss programs are often recommended to obese patients with LBP.

PURPOSE

To assess the efficacy of a pilot, multidisciplinary, medically supervised, nonsurgical weight loss program involving meal replacement, caloric restriction, education, exercise, and group therapy at reducing the severity of LBP in obese adults.

STUDY DESIGN

Pilot prospective cohort study.

PATIENT SAMPLE

A total of 46 obese adults (mean body mass index [BMI] 44.7±7.6 kg/m2) referred to an academic hospital for a multidisciplinary, medically supervised, nonsurgical weight loss program who reported LBP were enrolled.

OUTCOME MEASURES

The severity of LBP was measured using the Numerical Pain Scale (NPS) and modified Oswestry Disability Index (ODI) at baseline (Week 1), Week 14, and Week 53; weight, BMI, dietary adherence, and physical activity levels were also measured.

METHODS

The 52-week weight loss program was administered by a team of physicians, dietitians, exercise specialists, and nurses and included liquid meal replacements for 12 weeks, followed by supervised caloric restriction diets for 13 weeks. Participants also attended weekly group therapy and educational meetings for the first 26 weeks, after which they were instructed to continue caloric restriction diets, engage in 60 to 90 minutes of daily physical activity, and attend monthly group meetings for an additional 26 weeks.

RESULTS

At baseline, NPS was mild in 61% (n=28), moderate in 30% (n=14), and severe in 9% (n=4), whereas ODI was moderate in 48% (n=22), severe in 17% (n=8), and crippling in 4% (n=2). At Week 14 (n=42; 92% follow-up), there were significant improvements in NPS (p=.001) and ODI (p=.0005), and significant weight loss (p<.0001). At Week 53 (n=28; 61% follow-up), there was a trend toward improvement in NPS (p=.07), significant improvement in ODI (p=.0009), and significant weight loss (p=.0005); reduction in BMI was significantly associated with clinically important improvements in ODI (p=.046).

CONCLUSIONS

This pilot prospective cohort study suggests that a 52-week multidisciplinary, medically supervised, nonsurgical weight loss program in obese patients with LBP improved both pain and function.

Causal assessment of workplace manual handling or assisting patients and low back pain: results of a systematic review

BACKGROUND CONTEXT

Low back pain (LBP) is a common musculoskeletal disorder associated with a considerable social and economic burden within the working-age population. Despite an unclear etiology, numerous physical activities are suspected of leading to LBP. Declaring a causal relationship between occupational activities and LBP remains challenging and requires a methodologically rigorous approach.

PURPOSE

To conduct a systematic review focused on assessing the potentially causal relationship between workplace manual handling or assisting patients and LBP.

STUDY DESIGN

Systematic review of the literature.

SAMPLES

Studies reporting an association between workplace manual handling or assisting patients and LBP.

OUTCOME MEASURES

Numerical association between different levels of exposure to manual handling or assisting patients, and the presence or severity of LBP.

METHODS

A systematic review was conducted using Medline, EMBASE, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and content experts. The methodological quality of each study was assessed using a modified Newcastle-Ottawa Scale (NOS) for observational studies. The overall level of evidence supporting various Bradford-Hill criteria for causality for each category of manual handling or assisting patients and type of LBP was then evaluated. Studies were deemed of higher quality if they received a score of five or more on the modified NOS and used appropriate statistical analysis methods.

RESULTS

This search yielded 2,766 citations, and 32 studies met the eligibility criteria. Three high-quality studies reported on manual handling and LBP, including two prospective cohorts and one cross-sectional design. None demonstrated a significant association in most of their multivariate risk estimates. One study was able to assess dose-response and temporality, but its results did not support these criteria. Only one study discussed the biological plausibility of this association. Four high-quality studies evaluated assisting patients and LBP, including two case-controls, one cross-sectional, and one prospective cohort design. These studies were consistent in reporting no significant association. Two studies demonstrated a nonsignificant dose-response trend, and two studies discussed the biological plausibility of this association. No studies were able to demonstrate the temporality or experiment criteria.

CONCLUSIONS

The studies reviewed did not support a causal association between workplace manual handling or assisting patients and LBP in a Bradford-Hill framework. Conflicting evidence in specific subcategories of assisting patients was identified, suggesting that tasks such as assisting patients with ambulation may possibly contribute to LBP. It appears unlikely that workplace manual handling or assisting patients is independently causative of LBP in the populations of workers studied.

Causal assessment of occupational carrying and low back pain: results of a systematic review

BACKGROUND CONTEXT

Occupational low back pain (LBP) is a common musculoskeletal disorder that results in high healthcare use and a heavy societal burden from morbidity and medical costs. The etiology of LBP is unclear, although numerous physical activities in the workplace have been implicated in its development. Determining the causal relationship between LBP and specific occupational activities requires a rigorous methodological approach.

PURPOSE

To conduct a systematic review of the scientific literature focused on establishing a causal relationship between occupational carrying and LBP.

STUDY DESIGN

Systematic review of the literature was performed.

SAMPLE

Studies reporting an association between occupational carrying and LBP.

OUTCOME MEASURES

Numerical association between different levels of exposure to occupational carrying and the presence or severity of LBP.

METHODS

A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship between occupational carrying and LBP by using the commonly used Bradford-Hill framework. The literature was searched using Medline, Embase, CINAHL, Cochrane Library, the Occupational Safety and Health (OSH-ROM) database, gray literature (eg, studies not published in peer-reviewed journals), hand-searching occupational health journals, reference lists of included studies, and content experts. Study quality was evaluated using a modified version of the Newcastle-Ottawa Scale. Levels of evidence supporting specific Bradford-Hill criteria were evaluated for different categories of carrying and types of LBP outcomes.

RESULTS

This search yielded 2,766 citations. A total of nine high-quality studies reported on occupational carrying and LBP, including four case-control studies and five prospective cohort studies. These nine studies reported strong and consistent evidence against a statistical association between carrying and LBP. Three studies assessed dose-response, of which only one reported a dose-response trend that was not statistically significant. Five studies were able to assess temporality, but none reported results fulfilling this aspect of causality. The biological plausibility of carrying and LBP was not discussed in any of the nine studies. None of these studies attempted to evaluate the experiment criterion by devising studies in which the exposure to carrying and level of LBP could be measured before and after implementing a strategy aimed at reducing carrying in the workplace to determine its effect on LBP.

CONCLUSIONS

This review failed to identify high-quality studies that supported any of the Bradford-Hill criteria to establish causality between occupational carrying and LBP. Based on these results, it is unlikely that occupational carrying is independently causative of LBP in the populations of workers studied.

Causal assessment of occupational lifting and low back pain: results of a systematic review

BACKGROUND CONTEXT

Low back pain (LBP) is a disorder that commonly affects the working population, resulting in disability, health-care utilization, and a heavy socioeconomic burden. Although the etiology of LBP remains uncertain, occupational activities have been implicated. Evaluating these potentially causal relationships requires a methodologically rigorous approach. Occupational repetitive and/or heavy lifting is widely thought to be a risk factor for the development of LBP.

PURPOSE

To conduct a systematic review of the scientific literature to evaluate the causal relationship between occupational lifting and LBP.

STUDY DESIGN

Systematic review of the literature.

SAMPLE

Studies reporting an association between occupational lifting and LBP.

OUTCOME MEASURES

Numerical association between different levels of exposure to occupational lifting and the presence or severity of LBP.

METHODS

A search was conducted using Medline, EMBASE, CINAHL, Cochrane Library, OSH-ROM, gray literature (eg, reports not published in scientific journals), hand-searching occupational health journals, reference lists of included studies, and content experts. Evaluation of study quality was performed using a modified version of the Newcastle-Ottawa Scale. Levels of evidence were evaluated for specific Bradford-Hill criteria (association, dose-response, temporality, experiment, and biological plausibility).

RESULTS

This search yielded 2,766 citations, of which 35 studies met eligibility criteria and 9 were considered high methodological quality studies, including four case-controls and five prospective cohorts. Among the high-quality studies, there was conflicting evidence for association with four studies reporting significant associations and five studies reporting nonsignificant results. Two of the three studies that assessed dose-response demonstrated a nonsignificant trend. There were no significant risk estimates that demonstrated temporality. No studies were identified that satisfied the experiment criterion. Subgroup analyses identified certain types of lifting and LBP that had statistically significant results, but there were none that satisfied more than two of the Bradford-Hill criteria.

CONCLUSIONS

This review uncovered several high-quality studies examining a relationship between occupational lifting and LBP, but these studies did not consistently support any of the Bradford-Hill criteria for causality. There was moderate evidence of an association for specific types of lifting and LBP. Based on these results, it is unlikely that occupational lifting is independently causative of LBP in the populations of workers studied. Further research in specific subcategories of lifting would further clarify the presence or absence of a causal relationship.

Causal assessment of occupational standing or walking and low back pain: results of a systematic review

BACKGROUND CONTEXT

Low back pain (LBP) is a widespread musculoskeletal condition that frequently occurs in the working-age population. Numerous occupational physical activities have been implicated in its etiology.

PURPOSE

To conduct a systematic review establishing a causal relationship between occupational standing or walking and LBP.

STUDY DESIGN

Systematic review of the literature.

SAMPLE

Studies reporting an association between occupational standing or walking and LBP.

OUTCOME MEASURES

Numerical association between exposure to standing or walking and the presence of LBP.

METHODS

A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford-Hill criteria for causality, between occupational standing or walking and LBP. A search was conducted using MEDLINE, Embase, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and expert knowledge. Evaluation of methodological quality was performed using a modified Newcastle-Ottawa Scale.

RESULTS

This search yielded 2,766 citations. Eighteen studies met the inclusion criteria. Five were high-quality studies related to standing, and two were high-quality studies related to walking. For occupational standing and LBP, there was moderate to strong evidence against the association criterion, the only study examining dose response did not support this criterion, four studies examining temporality failed to support this criterion, and only one study discussed the biological plausibility criterion. For occupational walking and LBP, there was moderate evidence against a causal relationship with respect to the association, temporality, dose response, and biological plausibility criteria. No studies assessed the experiment criterion for these activities.

CONCLUSIONS

A summary of existing studies was not able to find any high-quality studies that satisfied more than two of the Bradford-Hill causation criteria for occupational standing or walking and LBP. Based on the evidence reviewed, it is unlikely that occupational standing or walking is independently causative of LBP in the populations of workers studied.

Causal assessment of awkward occupational postures and low back pain: results of a systematic review

BACKGROUND CONTEXT

Low back pain (LBP) is a prevalent and costly musculoskeletal disorder that often occurs in the working-age population. Although numerous physical activities have been implicated in its complex etiology, determining causation remains challenging and requires a methodologically rigorous approach.

PURPOSE

To conduct a systematic review of the scientific literature focused on establishing a causal relationship between awkward occupational postures and LBP.

STUDY DESIGN

Systematic review of the literature using MEDLINE, EMBASE, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and experts. Evaluation of methodological quality using a modified Newcastle-Ottawa Scale for observational studies. Summary levels of evidence for each of the Bradford Hill criteria for causality for each category of awkward occupational posture and type of LBP.

SAMPLE

Studies reporting an association between awkward occupational postures and LBP.

OUTCOME MEASURES

Numerical association between different levels of exposure to awkward occupational postures and the presence or severity of LBP.

METHODS

A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford Hill criteria, between awkward occupational postures and LBP.

RESULTS

This search yielded 2,766 citations. Eight high-quality studies reported on awkward occupational postures and LBP. Three were case-control studies, one was cross-sectional, and four were prospective cohort studies. There was strong evidence for consistency of no association between awkward occupational postures and LBP, with only two studies demonstrating significant associations in most of their risk estimates compared with six studies reported mainly nonsignificant associations. Two studies assessed dose response, with one study demonstrating a nonsignificant dose-response trend. Three studies were able to assess temporality, but all demonstrated nonsignificant risk estimates. Biological plausibility was discussed by two studies. There was no available evidence to assess the experiment criterion for causality.

CONCLUSIONS

There was strong evidence from six high-quality studies that there was no association between awkward postures and LBP. Similarly, there was strong evidence from three high-quality studies that there was no temporal relationship. Moreover, subgroup analyses identified only a handful of studies that demonstrated only weak associations and no evidence for other aspects of causality in certain specific subcategories. It is therefore unlikely that awkward occupational postures are independently causative of LBP in the populations of workers studied.

Causal assessment of occupational bending or twisting and low back pain: results of a systematic review

BACKGROUND CONTEXT

Low back pain (LBP) is a common musculoskeletal disorder that often occurs in the working-age population. Although numerous physical activities have been implicated in its etiology, determining causation remains challenging and requires a methodologically rigorous approach.

PURPOSE

To conduct a systematic review focused on establishing a causal relationship between occupational bending or twisting and LBP.

STUDY DESIGN

A systematic review of the literature using Medline, Embase, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and experts. Evaluation of methodological quality using a modified Newcastle-Ottawa Scale for observational studies. Summary levels of evidence for each of the Bradford-Hill criteria for causality for each category of bending or twisting and type of LBP.

SAMPLE

Studies reporting an association between occupational bending or twisting and LBP.

OUTCOME MEASURES

Numerical association between different levels of exposure to bending or twisting and the presence or severity of LBP.

METHODS

A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford-Hill criteria, between occupational bending or twisting and LBP.

RESULTS

This search yielded 2,766 citations. Ten high-quality studies reported on bending and LBP. Five were case-control studies and five were prospective cohort studies. There was conflicting evidence for association, with five studies demonstrating significant associations in the majority of their risk estimates, but no evidence for consistency. Seven studies assessed dose response, with four studies demonstrating a nonsignificant dose-response trend. Four studies were able to assess temporality, but only one demonstrated significant risk estimates. Biological plausibility was discussed by two studies. There was no available evidence for experiment. Seven high-quality studies reported on twisting and LBP. Two were case-control studies and five were prospective cohort studies. Three studies reported significant associations in the majority of their risk estimates, with no evidence for consistency. Three studies demonstrated a nonsignificant dose-response trend. Two studies were able to assess temporality, but only one study was able to demonstrate significant risk estimates. Two studies discussed biological plausibility. There was no available evidence for experiment.

CONCLUSIONS

A summary of existing studies was not able to find high-quality studies that satisfied more than three of the Bradford-Hill criteria for causation for either occupational bending or twisting and LBP. Conflicting evidence in multiple criteria was identified. This suggests that specific subcategories could contribute to LBP. However, the evidence suggests that occupational bending or twisting in general is unlikely to be independently causative of LBP.

Effect of stage duration on physiological variables commonly used to determine maximum aerobic performance during cycle ergometry

In this study, we examined the effect of stage duration on physiological variables commonly used to determine maximum aerobic performance during cycle ergometry. Ten recreationally trained males (mean age 27.8 +/- 7.1 years; BMI 24.3 +/- 2.5 kg x m(-2); VO2max 52.5 +/- 5.9 ml x kg(-1) x min(-1)) performed three different stage duration protocols on two separate occasions. Each short stage (SS; 1-min stages), long stage (LS; 3-min stages), and constant load + short stage (CL + SS; 4-min constant load followed by 1-min stages) protocol started at 50 W with increments of 30 W. The physiological variables measured included: time to maximum, maximum workload, maximum oxygen consumption (VO2max), maximum heart rate, maximum rating of perceived exertion, maximum blood lactate concentration, and maximum respiratory exchange ratio. The ventilatory threshold was calculated for every trial of the three protocols. There was no difference in VO2max, but maximum heart rate was higher in the LS protocol (P<0.05). Maximum respiratory exchange ratio varied between the protocols (P<0.05), while maximum workload differed between the SS and LS protocols, and the LS and CL + SS protocols (P<0.0001). The physiological variables were comparable between trials for the SS and CL + SS protocols, but maximum workload and VO2max differed for the LS protocol (P<0.05). Workload at the ventilatory threshold was lower for the LS protocol (P<0.05). Heart rate at the ventilatory threshold was different between the LS and CL + SS protocols (P<0.05). Performing a test involving 1- or 3-min stage durations on a single occasion was appropriate for the determination of VO2max and the ventilatory threshold. However, the disparity in heart rate and workload could result in differences in mechanical and physiological work being undertaken. Consistent use of a protocol may alleviate errors during exercise prescription.

Day-to-day variance in measurement of resting metabolic rate using ventilated-hood and mouthpiece & nose-clip indirect calorimetry systems

BACKGROUND

To know if the magnitude of change in resting metabolic rate (RMR) observed during an intervention is meaningful, it is imperative to first identify the variability that occurs within individuals from day to day under normal conditions. The 2 most common systems used to measure RMR involve a ventilated hood or a mouthpiece & nose clip to collect expired gases. The variation in measurement using these 2 approaches has not been systematically compared.

METHODS

RMR was measured in 10 healthy adults during 5 separate testing sessions within a 2-week period where usual diet and physical activity were maintained. Each testing session consisted of one measurement of RMR using a ventilated hood system, followed by another using a mouthpiece & nose-clip system.

RESULTS

No significant difference in RMR was evident between measurement sessions using either indirect calorimeter. Oxygen consumption and RMR were significantly higher using the mouthpiece & nose-clip system. Average within-individual coefficient of variation for RMR was significantly lower for the ventilated-hood system. RMR measures were consistently lower using the ventilated-hood system by an average of 94.5 +/- 63.3 kcal. Day-to-day variance was between 2% and 4% for both systems.

CONCLUSIONS

The use of either system is appropriate for assessing RMR in clinical and research settings, but alternating between systems should be undertaken with caution. A change in RMR must be greater than approximately 6% (96 kcal/d; 1.2 kcal/kg/d) or approximately 8% (135 kcal/d; 1.7 kcal/kg/d) when using a ventilated-hood system or a mouthpiece & nose-clip system, respectively, to observe any meaningful intervention-related differences within individuals.

Use of [14C]-sodium bicarbonate/urea to measure physical activity induced increases in total energy expenditure in free-living healthy males

The aim of this study was to evaluate the utility of the [(14)C]-sodium bicarbonate/urea technique to detect physical activity-induced increases in total energy expenditure in free-living healthy men. Thirteen healthy males aged 34.1 +/- 11.7 yrs with body mass index 24.1 +/- 3.1 kg/m(2) were studied on three separate occasions, during which [(14)C]-bicarbonate was infused over 48-hours and urine was collected during the second 24-hours. On three separate occasions and in random order, subjects either remained sedentary, or performed a bout of physical activity on an electro-magnetically braked cycle ergometer sufficient to increase energy expenditure by 7% or 11% above predicted sedentary total energy expenditure. Urine samples were analyzed to evaluate the amount of [(14)C]-bicarbonate incorporated into urinary urea, thereby reflecting the amount of CO(2) produced per day, and upon conversion, the number of kilojoules of energy expended in 24-hours. All 13 subjects successfully completed the two physical activity treatments and there were no adverse events. As measured by the [(14)C]-urea assay, mean total energy expenditure values were not significantly different between sedentary activity (17902 +/- 905 kJ/day), the physical activity treatment designed to increase TEE by 7% (17701 +/- 594 kJ/day) and the physical activity treatment designed to increase TEE by 11% (18538 +/- 485 kJ/day) (P=0.668). In conclusion, although the [(14)C]-sodium bicarbonate/urea technique was well tolerated and did not interfere with normal daily activities, it was not able to accurately measure physical activity-induced increases in EE in the range of 7-11% above predicted sedentary total energy expenditure.