Composite psychosocial risk based on the fear avoidance model in patients undergoing anterior cruciate ligament reconstruction: Cluster-based analysis.

OBJECTIVES: To examine associations between preoperative fear-avoidance model (FAM) risk subgroup status and patient expectation of surgical success with postoperative outcomes at 6 and 12 months after anterior cruciate ligament reconstruction (ACLR). DESIGN: Cohort study. SETTING: Academic medical center. PARTICIPANTS: 54 patients (25 females) undergoing unilateral ACLR. MAIN OUTCOME MEASURES: Cluster analysis distinguished FAM risk subgroups based on preoperative fear of movement/reinjury, self-efficacy, and pain catastrophizing. Preoperative expectation for surgical success was assessed with a numeric rating scale. Six and 12-month outcomes included Subjective Patient Outcomes for Return to Sport, Knee Injury and Osteoarthritis Outcome Score (KOOS) sports/recreation and quality of life, and International Knee Documentation Committee (IKDC) Subjective Knee Form. RESULTS: Thirteen (24%) patients were "moderate-to-high FAM risk." Moderate-to-high FAM risk patients had lower odds of return to sport at 12 months (OR = 0.3, p = .05) and lower KOOS sports/recreation at 6 months (st. beta = -0.27, p = .05), KOOS quality of life at 12 months (st. beta = -0.42, p = .007), and IKDC at 6 (st. beta = -0.29, p = .04) and 12 months (st. beta = -0.47, p = .001). Higher expectation was associated with lower 6-month IKDC (st. beta = -0.36, p = .008) and 12-month KOOS quality of life (st. beta = -0.29, p = .05). CONCLUSIONS: Preoperative FAM risk influences patient-reported outcomes and return to sport at 6 and 12 months.

Effects of flight altitude on the lift generation of monarch butterflies: from sea level to overwintering mountain.

Aerodynamic efficiency behind the annual migration of monarch butterflies, the longest among insects, is an unsolved mystery. Monarchs migrate 4000 km at high-altitudes to their overwintering mountains in Central Mexico. The air is thinner at higher altitudes, yielding reduced aerodynamic drag and enhanced range. However, the lift is also expected to reduce in lower density conditions. To investigate the ability of monarchs to produce sufficient lift to fly in thinner air, we measured the climbing motion of freely flying monarchs in high-altitude conditions. An optical method was used to track the flapping wing and body motions inside a large pressure chamber. The air density inside the chamber was reduced to recreate the higher altitude densities. The lift coefficient generated by monarchs increased from 1.7 at the sea-level to 9.4 at 3000 m. The correlation between this increase and the flapping amplitude and frequency was insignificant. However, it strongly correlated to the effective angle of attack, which measures the wing to body velocity ratio. These results support the hypothesis that monarchs produce sufficiently high lift coefficients at high altitudes despite a lower dynamic pressure.

Salt and water balance after sweat loss: A study of Bikram yoga.

Bikram yoga is practiced in a room heated to 105°F with 40% humidity for 90 min. During the class a large volume of water and electrolytes are lost in the sweat, specifically, sodium is lost, the main cation of the extracellular fluid. There is little known about the volume of sweat and the amount of sodium lost in sweat during Bikram yoga or the optimum quantity of fluid required to replace these losses. The participants who took part in this small feasibility study were five females with a mean age of 47.4 ± 4.7 years and 2.6 ± 1.6 years of experience at Bikram yoga. The total body weight, water consumed, serum sodium concentration, serum osmolality, and serum aldosterone levels were all measured before and after a Bikram yoga practice. Sweat sodium chloride concentration and osmolality were measured at the end of the practice. The mean estimated sweat loss was 1.54 ± 0.65 L, while the amount of water consumed during Bikram yoga was 0.38 ± 0.22 L. Even though only 25% of the sweat loss was replenished with water intake during the Bikram yoga class, we did not observe a change in serum sodium levels or serum osmolality. The sweat contained 82 ± 16 mmol/L of sodium chloride for an estimated total of 6.8 ± 2.1 g of sodium chloride lost in the sweat. The serum aldosterone increased 3.5-fold from before to after Bikram yoga. There was a decrease in the extracellular body fluid compartment of 9.7%. Sweat loss in Bikram yoga predominately produced a volume depletion rather than the dehydration of body fluids. The sweating-stimulated rise in serum aldosterone levels will lead to increased sodium reabsorption from the kidney tubules and restore the extracellular fluid volume over the next 24 hr.

Early postoperative physical activity and function: a descriptive case series study of 53 patients after lumbar spine surgery.

BACKGROUND: The purpose of this prospective case series study was to compare changes in early postoperative physical activity and physical function between 6 weeks and 3 and 6 months after lumbar spine surgery. METHODS: Fifty-three patients (mean [95% confidence interval; CI] age = 59.2 [56.2, 62.3] years, 64% female) who underwent spine surgery for a degenerative lumbar condition were assessed at 6 weeks and 3- and 6-months after surgery. The outcomes were objectively-measured physical activity (accelerometry) and patient-reported and objective physical function. Physical activity was assessed using mean steps/day and time spent in moderate to vigorous physical activity (MVPA) over a week. Physical function measures included Oswestry Disability Index (ODI), 12-item Short Form Health Survey (SF-12), Timed Up and Go (TUG), and 10-Meter Walk (10 MW). We compared changes over time in physical activity and function using generalized estimating equations with robust estimator and first-order autoregressive covariance structure. Proportion of patients who engaged in meaningful physical activity (e.g., walked at least 4400 and 6000 steps/day or engaged in at least 150 min/week in MVPA) and achieved clinically meaningful changes in physical function were compared at 3 and 6 months. RESULTS: After surgery, 72% of patients initiated physical therapy (mean [95%CI] sessions =8.5 [6.6, 10.4]) between 6 weeks and 3 months. Compared to 6 weeks post-surgery, no change in steps/day or time in MVPA/week was observed at 3 or 6 months. From 21 to 23% and 9 to 11% of participants walked at least 4400 and 6000 steps/day at 3 and 6 months, respectively, while none of the participants spent at least 150 min/week in MVPA at these same time points. Significant improvements were observed on ODI, SF-12, TUG and 10 MW (p <  0.05), with over 43 to 68% and 62 to 87% achieving clinically meaningful improvements on these measures at 3 and 6 months, respectively. CONCLUSION: Limited improvement was observed in objectively-measured physical activity from 6 weeks to 6 months after spine surgery, despite moderate to large function gains. Early postoperative physical therapy interventions targeting physical activity may be needed.

Calcium loss in sweat does not stimulate PTH release: A study of Bikram hot yoga.

It has been hypothesized that sweat loss during exercise causes a disruption in calcium homeostasis that activates bone resorption and over time leads to low bone mineral density. The purpose of this small pilot study was to determine whether dermal calcium loss from a bout of excessive sweating during light intensity physical activity triggers an increase in biomarkers of bone resorption. Biochemical markers related to bone homeostasis were measured before and after a 90 min Bikram hot yoga practice performed in a room heated to 105 °F with 40 % humidity. Participants were five females with a mean age of 47.4 ± 4.7 years. Nude body weight, serum total calcium (Ca2+), free ionized calcium, albumin, parathyroid hormone (PTH) and CTX-I were measured before and after a Bikram hot yoga practice. Mean estimated sweat loss was 1.54 ± 0.65 L, which elicited a 1.9 ± 0.9 % decrease in participant's body weight. Mean Ca2+ concentration in sweat was 2.9 ± 1.7 mg/dl and the estimated mean total calcium lost was 41.3 ± 16.4 mg. Serum ionized Ca2+ increased from 4.76 ± 0.29 mg/dl to 5.35 ± 0.36 mg/dl after the Bikram hot yoga practice (p = 0.0118). Serum PTH decreased from pre- 33.9 ± 3.3 pg/ml to post- 29.9 ± 2.1 pg/ml yoga practice (p = 0.0015) when adjusted for hemoconcentration (PTHADJ), implying a decrease in PTH secretion. We conclude that calcium loss in sweat during 90 min of Bikram hot yoga did not trigger an increase in PTH secretion and did not initiate bone resorption.

Psychosocial Mechanisms of Cognitive-Behavioral-Based Physical Therapy Outcomes After Spine Surgery: Preliminary Findings From Mediation Analyses.

OBJECTIVE: Changing Behavior through Physical Therapy (CBPT), a cognitive-behavioral-based program, has been shown to improve outcomes after lumbar spine surgery in patients with a high psychosocial risk profile; however, little is known about potential mechanisms associated with CBPT treatment effects. The purpose of this study was to explore potential mediators underlying CBPT efficacy after spine surgery. METHODS: In this secondary analysis, 86 participants were enrolled in a randomized trial comparing a postoperative CBPT (n = 43) and education program (n = 43). Participants completed validated questionnaires at 6 weeks (baseline) and 3 and 6 months following surgery for back pain (Brief Pain Inventory), disability (Oswestry Disability Index), physical health (12-Item Short-Form Health Survey), fear of movement (Tampa Scale for Kinesiophobia), pain catastrophizing (Pain Catastrophizing Scale), and pain self-efficacy (Pain Self-Efficacy Questionnaire). Parallel multiple mediation analyses using Statistical Package for the Social Sciences (SPSS) were conducted to examine whether 3- and 6-month changes in fear of movement, pain catastrophizing, and pain self-efficacy mediate treatment outcome effects at 6 months. RESULTS: Six-month changes, but not 3-month changes, in fear of movement and pain self-efficacy mediated postoperative outcomes at 6 months. Specifically, changes in fear of movement mediated the effects of CBPT treatment on disability (indirect effect = -2.0 [95% CI = -4.3 to 0.3]), whereas changes in pain self-efficacy mediated the effects of CBPT treatment on physical health (indirect effect = 3.5 [95% CI = 1.2 to 6.1]). CONCLUSIONS: This study advances evidence on potential mechanisms underlying cognitive-behavioral strategies. Future work with larger samples is needed to establish whether these factors are a definitive causal mechanism. IMPACT: Fear of movement and pain self-efficacy may be important mechanisms to consider when developing and testing psychologically informed physical therapy programs.

Factors associated with mobility apprehension in persons with lower limb amputation.

BACKGROUND: Factors that are related to mobility apprehension were measured in a sample of persons with lower-limb amputation. OBJECTIVES: The purpose was to determine whether intensity, interference, or catastrophizing are associated with mobility apprehension. STUDY DESIGN: Cross-sectional study. METHODS: Persons with amputation of a lower limb who were attending a national limb loss conference were recruited to complete a survey. Subjects were administered the Tampa Scale for Kinesiophobia to measure mobility apprehension. The Brief Pain Inventory was administered to quantify the affect of pain on general activity, walking ability, and enjoyment of life. The Pain Catastrophizing Scale was administered to assess the tendency to ruminate and magnify pain sensations. A multivariable linear regression was performed to determine factors associated with mobility apprehension. RESULTS: Fifty-three people with lower-limb amputation participated in the study. The mean (standard deviation) score for mobility apprehension was 34.2 (6.0). Mean (standard deviation) pain intensity and interference scores were 1.6 (1.7) and 2.5 (2.6), respectively. The mean (standard deviation) pain catastrophizing score was 9.1 (10). Pain catastrophizing was the only variable associated with higher mobility apprehension (ß = 0.31, p < 0.001, R2 = 0.32). Results suggest that for every one-point increase in the pain catastrophizing score, mobility apprehension will increase by 0.3 of a point. CONCLUSION: These preliminary results suggest that pain catastrophizing was related to mobility apprehension in this cohort of persons with lower-limb amputation. This relationship indicates that the exploration of avoidance behaviors, such as pain catastrophizing, may be useful when developing a program for physical rehabilitation. CLINICAL RELEVANCE: Pain catastrophizing, an avoidance behavior, may be associated with higher levels of mobility apprehension in persons with major lower-limb amputation. Understanding the impact of fear-avoidance behavior will allow clinicians to identify individuals at risk for poor outcomes following amputation surgery and to develop psychological strategies to complement treatment.

Combined Aerobic and Resistance Training Increases Stretch- Shortening Cycle Potentiation and Walking Economy in Postmenopausal Women.

PURPOSE: Secondary analyses were performed to test whether combined aerobic and resistance training altered walking economy (i.e., net oxygen uptake) and/or stretch-shortening cycle potentiation (SSCP). A further objective was to determine if walking economy and SSCP were related before or after training. METHODS: Ninety-two postmenopausal women were enrolled wherein 76 completed 16 weeks of supervised aerobic and resistance training. Participants were randomized to one of three training groups based on frequencies: (a) 1 d⋅wk-1 (n = 23); (b) 2 d⋅wk-1 (n = 30) or; (c) 3 d⋅wk-1 (n = 23). Following assessments were performed at baseline and post-training. Indirect calorimetry was used to measure maximal oxygen uptake () and walking economy (submaximal - resting = net ) during a graded exercise test and steady-state treadmill task, respectively. SSCP was determined by measuring the difference between a concentric (CO) and counter-movement (CM) leg press throw. RESULTS: , walking economy, CO and CM velocity were significantly improved (p < 0.05) for all training groups, however; no time by group interactions were observed. Paired t-tests revealed participants exercise training 2 d⋅wk-1 exhibited a significant time effect for SSCP (+0.04 ± 0.09 ms-1; p = 0.03). At baseline, multiple linear regression showed a negative relationship between walking net and SSCP (r = -0.22; p < 0.04) adjusted for relative proportion of . No such relationship was found post-training. CONCLUSION: Among older postmenopausal women, our results indicate that irrespective of frequency of training, 16 weeks of combined aerobic and resistance exercise training increased ease of walking and economy. Additionally, only participants exercising 2 d⋅wk-1 exhibited significant improvement in SSCP.

Relationship between V̇o2peak, cycle economy, and mitochondrial respiration in untrained/trained.

Aerobic capacity is negatively related to locomotion economy. The purpose of this paper is to determine what effect aerobic exercise training has on the relationship between net cycling oxygen uptake (inverse of economy) and aerobic capacity [peak oxygen uptake (V̇o2peak)], as well as what role mitochondrial coupled and uncoupled respiration may play in whole body aerobic capacity and cycling economy. Cycling net oxygen uptake and V̇o2peak were evaluated on 31 premenopausal women before exercise training (baseline) and after 8-16 wk of aerobic training. Muscle tissue was collected from 15 subjects at baseline and post-training. Mitochondrial respiration assays were performed using high-resolution respirometry. Pre- (r = 0.46, P < 0.01) and postexercise training (r = 0.62, P < 0.01) V̇o2peak and cycling net oxygen uptake were related. In addition, uncoupled and coupled fat respiration were related both at baseline (r = 0.62, P < 0.01) and post-training (r = 0.89, P < 01). Post-training coupled (r = 0.74, P < 0.01) and uncoupled carbohydrate respiration (r = 0.52, P < 05) were related to cycle net oxygen uptake. In addition, correlations between V̇o2peak and cycle net oxygen uptake persist both at baseline and after training, even after adjusting for submaximal cycle respiratory quotient (an index of fat oxidation). These results suggest that the negative relationship between locomotion economy and aerobic capacity is increased following exercise training. In addition, it is proposed that at least one of the primary factors influencing this relationship has its foundation within the mitochondria. Strong relationships between coupled and uncoupled respiration appear to be contributing factors for this relationship.NEW & NOTEWORTHY The negative relationship between cycle economy and aerobic capacity is increased following exercise training. The strong relationship between coupled and uncoupled respiration, especially after training, appears to be contributing to this negative relationship between aerobic capacity and cycling economy, suggesting that mitochondrial economy is not increased following aerobic exercise training. These results are suggestive that training programs designed to improve locomotion economy should focus on changing biomechanics.

Resistance Training Is Associated With Higher Lumbar Spine and Hip Bone Mineral Density in Competitive Male Cyclists.

Mathis, SL, and Caputo, JL. Resistance training is associated with higher lumbar spine and hip bone mineral density in competitive male cyclists. J Strength Cond Res 32(1): 274-279, 2018-In contrast to other athletic activities, competitive cycling is associated with low areal bone mineral density (BMD). This investigation evaluated training and dietary factors associated with BMD in a sample of competitive male cyclists. Lumbar spine, total hip, femoral neck, and femoral trochanter BMD were measured with dual X-ray absorptiometry in 40 cyclists at the start of a cycling season. Participants reported weekly hours of cycling and weight training, years of competitive cycling experience, and completed a 1-day dietary recall to allow estimation of dietary calcium intake. Multivariable linear regression analyses revealed that weight training was associated with higher BMD of the lumbar spine (ß = 0.001, t = 2.88, p = 0.01), hip (ß = 0.002, t = 4.95, p < 0.001), femoral neck (ß = 0.002, t = 5.31, p < 0.001), and femoral trochanter (ß = 0.002, t = 4.31, p < 0.001). No other factor was a predictor of preseason BMD in this sample. These data emphasize the need for competitive male cyclists to participate in weight training to maintain or increase bone mass of the lumbar spine and hip.

Cognitive-Behavioral-Based Physical Therapy for Patients With Chronic Pain Undergoing Lumbar Spine Surgery: A Randomized Controlled Trial.

UNLABELLED: The purpose of this study was to determine the efficacy of a cognitive-behavioral-based physical therapy (CBPT) program for improving outcomes in patients after lumbar spine surgery. A randomized controlled trial was conducted on 86 adults undergoing a laminectomy with or without arthrodesis for a lumbar degenerative condition. Patients were screened preoperatively for high fear of movement using the Tampa Scale for Kinesiophobia. Randomization to either CBPT or an education program occurred at 6 weeks after surgery. Assessments were completed pretreatment, posttreatment and at 3-month follow-up. The primary outcomes were pain and disability measured by the Brief Pain Inventory and Oswestry Disability Index. Secondary outcomes included general health (SF-12) and performance-based tests (5-Chair Stand, Timed Up and Go, 10-Meter Walk). Multivariable linear regression analyses found that CBPT participants had significantly greater decreases in pain and disability and increases in general health and physical performance compared with the education group at the 3-month follow-up. Results suggest a targeted CBPT program may result in significant and clinically meaningful improvement in postoperative outcomes. CBPT has the potential to be an evidence-based program that clinicians can recommend for patients at risk for poor recovery after spine surgery. PERSPECTIVE: This study investigated a targeted cognitive-behavioral-based physical therapy program for patients after lumbar spine surgery. Findings lend support to the hypothesis that incorporating cognitive-behavioral strategies into postoperative physical therapy may address psychosocial risk factors and improve pain, disability, general health, and physical performance outcomes.

Early postoperative fear of movement predicts pain, disability, and physical health six months after spinal surgery for degenerative conditions.

BACKGROUND CONTEXT: The fear-avoidance model offers a promising framework for understanding the development of chronic postoperative pain and disability. However, limited research has examined this model in patients undergoing spinal surgery. PURPOSE: To determine whether preoperative and early postoperative fear of movement predicts pain, disability, and physical health at 6 months following spinal surgery for degenerative conditions, after controlling for depressive symptoms and other potential confounding variables. STUDY DESIGN/SETTING: A prospective cohort study conducted at an academic outpatient clinic. PATIENT SAMPLE: One hundred forty-one patients undergoing surgery for lumbar or cervical degenerative conditions. OUTCOME MEASURES: Self-reported pain and disability were measured with the Brief Pain Inventory and the Oswestry Disability Index/Neck Disability Index, respectively. The physical composite scale of the 12-Item Short-Form Health Survey (SF-12) measured physical health. METHODS: Data collection occurred preoperatively and at 6 weeks and 6 months following surgery. Fear of movement was measured with the Tampa Scale for Kinesiophobia and depression with the Prime-MD PHQ-9. RESULTS: One hundred and twenty patients (85% follow-up) completed the 6-month postoperative assessment. Multivariable mixed-method linear regression analyses found that early postoperative fear of movement (6 weeks) predicted pain intensity, pain interference, disability, and physical health at 6-month follow-up (p<.05). Preoperative and early postoperative depression predicted pain interference, disability, and physical health. CONCLUSION: Results provide support for the fear-avoidance model in a postsurgical spine population. Early postoperative screening for fear of movement and depressive symptoms that do not acutely improve following surgical intervention appears warranted. Cognitive and behavioral strategies may be beneficial for postsurgical patients with high fear of movement and/or depressive symptoms.

The homeless orthopaedic trauma patient: follow-up, emergency room usage, and complications.

OBJECTIVES: To review homeless patients with orthopaedic trauma injuries and examine their emergency room (ER) usage, follow-up rates, and complication rates. DESIGN: Retrospective chart review. SETTING: Patients presenting to a level 1 trauma center with orthopaedic trauma injuries from 2001 to 2010. PATIENTS/PARTICIPANTS: Sixty-three uninsured homeless patients and 63 uninsured nonhomeless patients with orthopaedic trauma injuries were included. INTERVENTION: Homeless patients with orthopaedic trauma were identified through ER intake sheets and current procedural terminology code searches. MAIN OUTCOME MEASUREMENTS: ER usage, orthopaedic clinic follow-up, and complications. RESULTS: After the index visit to the ER for their orthopaedic trauma injuries, homeless patients demonstrated more ER visits and had fewer orthopaedic clinic follow-up visits than nonhomeless patients (P < 0.001). There were no significant differences among the type of complications (none, infection, hardware failure, and nonunion) between the homeless and the nonhomeless patients (P = 0.23). Operative homeless patients returned to the orthopaedic clinic for follow-up more than nonoperative homeless patients (mean = 5.4, SD = 7.6; and mean = 1.2, SD = 1.5, respectively; P < 0.001). CONCLUSIONS: Our data are the first to examine the problems associated with homelessness in the patient with orthopaedic trauma and demonstrate an increased challenge in the follow-up care. The orthopaedic surgeon must consider these issues in managing this complex patient population. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The financial burden of reexcising incompletely excised soft tissue sarcomas: a cost analysis.

BACKGROUND: Although survival outcomes have been evaluated between those undergoing a planned primary excision and those undergoing a reexcision following an unplanned resection, the financial implications associated with a reexcision have yet to be elucidated. METHODS: A query for financial data (professional, technical, indirect charges) for soft tissue sarcoma excisions from 2005 to 2008 was performed. A total of 304 patients (200 primary excisions and 104 reexcisions) were identified. Wilcoxon rank sum tests and χ2 or Fisher's exact tests were used to compare differences in demographics and tumor characteristics. Multivariable linear regression analyses were performed with bootstrapping techniques. RESULTS: The average professional charge for a primary excision was $9,694 and $12,896 for a reexcision (p<.001). After adjusting for tumor size, American Society of Anesthesiologists status, grade, and site, patients undergoing reexcision saw an increase of $3,699 in professional charges more than those with a primary excision (p<.001). Although every 1-cm increase in size of the tumor results in an increase of $148 for a primary excision (p=.006), size was not an independent factor in affecting reexcision charges. The grade of the tumor was positively associated with professional charges of both groups such that higher-grade tumors resulted in higher charges compared to lower-grade tumors (p<.05). CONCLUSIONS: Reexcision of an incompletely excised sarcoma results in significantly higher professional charges when compared to a single, planned complete excision. Additionally, when the cost of the primary unplanned surgery is considered, the financial burden nearly doubles.

Influence of resident education in correctly diagnosing extremity soft tissue sarcoma.

Background. One-third of all extremity soft tissue sarcomas are misdiagnosed and inappropriately excised without proper preoperative diagnosis and planning. This study aimed at examining the clinical judgment of residents in both general and orthopaedic surgery and at determining whether resident education plays a role in appropriately managing unknown soft tissue masses. Methods. A case-based survey was used to assess clinical decisions, practice patterns, and demographics. Aggregate response for all of the clinical cases by each respondent was correlated with the selections made for practice patterns and demographic data. Results. A total of 381 responses were returned. A higher percentage of respondents from the orthopaedic group (84.2%) noted having a dedicated STS rotation as compared to the general surgery group (35.8%) P < 0.001. Depth, size, and location of the mass, rate of growth, and imaging characteristics were considered to be important factors. Each additional year of training resulted in 10% increased odds of selecting the correct clinical decision for both groups. Conclusion. Our study showed that current residents in both orthopaedic surgery and general surgery are able to appropriately identify patients with suspicious masses. Continuing education in sarcoma care should be implemented beyond the years of residency training.

Risk factors of infection after ORIF of bicondylar tibial plateau fractures.

OBJECTIVES: This study was designed to evaluate risk factors of infection after bicondylar tibial plateau fractures. We hypothesized that open fractures and smoking would be associated with deep infection requiring reoperation. DESIGN: We retrospectively identified all bicondylar (AO/OTA 41-C) tibial plateau fractures treated operatively over an 8-year period from 2002 to 2010. SETTING: Single, high-volume, level 1 trauma center. PATIENTS/PARTICIPANTS: A total of 302 patients aged 18 years and older were identified as undergoing operative fixation of bicondylar (AO/OTA 41-C) tibial plateau fractures during this time period. INTERVENTION: Open reduction internal fixation of bicondylar (AO/OTA 41-C) tibial plateau fractures. MAIN OUTCOME MEASUREMENTS: Bivariate and multivariable logistic regression analyses were used to assess the association between patient demographics and clinical characteristics and deep infection requiring reoperation. Variables that were significant at P < 0.05 in bivariate analyses were entered into a multivariable logistic regression model. RESULTS: Forty-three (14.2%) of 302 patients developed deep infection requiring reoperation. Methicillin-resistant Staphylococcus aureus (MRSA) was cultured in 20 (46.5%) of 43 patients with deep infections. An external fixator was initially placed before definitive fixation in 81.4% of patients and definitive surgical treatment was delayed by an average of 17.5 days. Eighty-five (28.1%) patients required a reoperation after definitive fixation.Open fracture (OR, 3.44; P = 0.003), smoking (OR, 2.40; P = 0.02), compartment syndrome requiring fasciotomies (OR, 3.81; P = 0.01), and fractures requiring 2 incisions and 2 plates (OR, 3.19; P = 0.01) were all risk factors for deep infection requiring reoperation. CONCLUSIONS: In spite of a staged protocol with temporizing external fixation and delayed fixation, deep infection rate remained high. A disproportionate amount of MRSA (47%) was cultured from deep infections in this population, and MRSA prophylaxis may be considered. Smoking was the only patient modifiable predictor identified of deep infection, and patients should be informed of the increased risk of deep infection associated with their choice to continue smoking. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

The Relationship between Cortisol and Bone Mineral Density in Competitive Male Cyclists.

Objective. The purpose of this study was to determine whether race day cortisol was related to bone mineral density (BMD) in competitive male cyclists. A secondary purpose was to determine additional factors associated with BMD in competitive male cyclists. Methods. Measurements of lumbar spine and hip BMD were performed in 35 male competitors in a state championship cycling time trial event. Salivary cortisol was measured 10 minutes prior to the start of the race and 5 minutes after race finished. Participants reported daily calcium intake, age, years of bike training, races per season, and average weekly minutes spent riding a bike, weight training, and running on a survey. Results. Cortisol level increased significantly from pre- to postcompetition but was not significantly associated with BMD. Increased weekly minutes of weight training was associated with higher BMD of the lumbar spine and the hip. The increased number of years of cycling experience was associated with lower BMD of the femoral neck. Increased daily calcium intake was associated with higher BMD of the lumbar spine and femoral neck. Conclusions. Findings indicate that cyclists should participate in weight training and increase calcium intake in order to increase or maintain BMD of the lumbar spine and hip.