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In young healthy humans full expression of reflex cutaneous vasodilation is dependent on cyclooxygenase (COX)- and nitric oxide synthase (NOS)-dependent mechanisms. Chronic low-dose aspirin therapy attenuates reflex cutaneous vasodilation potentially through both platelet and vascular COX-dependent mechanisms. We hypothesized the contribution of COX-dependent vasodilators to reflex cutaneous vasodilation during localized acute COX inhibition would be attenuated in healthy middle-aged humans due to a shift toward COX-dependent vasoconstrictors. Four microdialysis fibers were placed in forearm skin of 13 middle-aged (53 +/- 2 yr) normotensive healthy humans, serving as control (Ringer), COX-inhibited (10 mM ketorolac), NOS-inhibited (10 mM N(G)-nitro-l-arginine methyl ester), and combined NOS- and COX-inhibited sites. Red blood cell flux was measured over each site by laser-Doppler flowmetry as reflex vasodilation was induced by increasing oral temperature (T(or)) 1.0 degrees C using a water-perfused suit. Cutaneous vascular conductance was calculated (CVC = flux/mean arterial pressure) and normalized to maximal CVC (CVC(max); 28 mM sodium nitroprusside). CVC(max) was not affected by localized microdialysis drug treatment (P > 0.05). Localized COX inhibition increased baseline (18 +/- 3%CVC(max); P < 0.001) compared with control (9 +/- 1%CVC(max)), NOS-inhibited (7 +/- 1%CVC(max)), and combined sites (10 +/- 1%CVC(max)). %CVC(max) in the COX-inhibited site remained greater than the control site with DeltaT(or) < or = 0.3 degrees C; however, there was no difference between these sites with DeltaT(or) > or = 0.4 degrees C. NOS inhibition and combined COX and NOS inhibition attenuated reflex vasodilation compared with control (P < 0.001), but there was no difference between these sites. Localized COX inhibition with ketorolac significantly augments baseline CVC but does not alter the subsequent skin blood flow response to hyperthermia, suggesting a limited role for COX-derived vasodilator prostanoids in reflex cutaneous vasodilation and a shift toward COX-derived vasoconstrictors in middle-aged human skin.

Background Previous work has established that physician attire influences patients' perceptions of their physicians. However, research from different specialties has disagreed regarding what kinds of physician attire might result in increased trust and confidence on the part of patients. Questions/Purposes The purpose of this study was to investigate how surgeon attire affects patients' perceptions of trust and confidence in an urban orthopaedic outpatient setting. Methods Eighty-five of 100 patients solicited completed a three-part questionnaire in the outpatient orthopaedic clinic at an urban teaching hospital. In the first section, participants viewed eight images, four of a male surgeon and four of a female surgeon wearing a white coat over formal attire, scrubs, business attire, and casual attire, and rated each image on a five-level Likert scale. Participants were asked how confident, trustworthy, safe, caring, and smart the surgeon appeared, how well the surgery would go, and how willing they would be to discuss personal information with the pictured surgeon. The participant ranked all images from most to least confident in the second part and the last section obtained demographic information from the patients. Surveys were scored using a five-level Likert scale and a Friedman test was used to detect statistical significance when comparing all attires. Similarly, the white coat was preferred to casual attire in all categories (confidence: MD, 0.810 ± 0.921; smart: MD, 0.493 ± 0.801; surgical skill: MD, 0.640 ± 0.880; ability to discuss: MD, 0.564 ± 0.988; trust: MD, 0.545 ± 0.836; safety: MD, 0.581 ± 0.860; caring: MD, 0.479 ± 0.852; p \ 0.001 for all comparisons). For the female surgeon, white coat and scrubs were not different, however the white coat was preferred to business attire in four of seven categories. Casual clothing was widely disliked in all categories for surgeons (men and women). When attire was compared for confidence on a scale, the white coat ranked Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research 1 editors and board members are on file with the publication and can be viewed on request. Each author certifies that his or her institution approved or waived approval for the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research. This study was performed at

WL. Reflex vasoconstriction in aged human skin increasingly relies on Rho kinase-dependent mechanisms during whole body cooling. Am J Physiol Heart Circ Physiol 297: H1792-H1797, 2009. First published August 28, 2009 doi:10.1152/ajpheart.00509.2009.-Primary human aging may be associated with augmented Rho kinase (ROCK)-mediated contraction of vascular smooth muscle and ROCK-mediated inhibition of nitric oxide synthase (NOS). We hypothesized that the contribution of ROCK to reflex vasoconstriction (VC) is greater in aged skin. Cutaneous VC was elicited by 1) whole body cooling [mean skin temperature (Tsk) ϭ 30.5°C] and 2) local norepinephrine (NE) infusion (1 ϫ 10 Ϫ6 M). Four microdialysis fibers were placed in the forearm skin of eight young (Y) and eight older (O) subjects for infusion of 1) Ringer solution (control), 2) 3 mM fasudil (ROCK inhibition), 3) 20 mM N G -nitro-L-arginine methyl ester (NOS inhibition), and 4) both ROCK ϩ NOS inhibitors. Red cell flux was measured by laser-Doppler flowmetry over each site. Cutaneous vascular conductance (CVC) was calculated as flux/mean arterial pressure and normalized to baseline CVC (%⌬CVCbaseline). VC was reduced at the control site in O during cooling (Y, Ϫ34 Ϯ 3; and O, Ϫ18 Ϯ 3%⌬CVCbaseline; P Ͻ 0.001) and NE infusion (Y, Ϫ53 Ϯ 4, and O, Ϫ41 Ϯ 9%⌬CVCbaseline; P ϭ 0.006). Fasudil attenuated VC in both age groups during mild cooling; however, this reduction remained only in O but not in Y skin during moderate cooling (Y, Ϫ30 Ϯ 5; and O, Ϫ7 Ϯ 1%⌬CVCbaseline; P ϭ 0.016) and was not altered by NOS inhibition. Fasudil blunted NE-mediated VC in both age groups (Y, Ϫ23 Ϯ 4; and O, Ϫ7 Ϯ 3%⌬CVCbaseline; P Ͻ 0.01). Cumulatively, these data indicate that reflex VC is more reliant on ROCK in aged skin such that approximately half of the total VC response to whole body cooling is ROCK dependent. skin blood flow; aging; temperature regulation; norepinephrine PERIPHERAL CUTANEOUS VESSELS constrict in response to cold exposure through distinct reflex and locally regulated mechanisms. Localized cooling of skin induces vasoconstriction (VC) that is partly mediated by both stimulation of ␣ 2 -adrenoreceptors by norepinephrine (NE) (9, 11) and upregulation of the downstream intracellular messenger Rho kinase (ROCK) (30, 31), whereas reflex sympathetically mediated VC relies on NE (ϳ60% of the VC response) and other coreleased sympathetic neurotransmitters (ϳ40%) (29,34).In aged skin (Ͼ60 yr), the reflex VC response is not only blunted but relies entirely on an already compromised adrenergic mechanism (18,(32)(33)(34). Furthermore, the vascular signaling pathways that couple adrenoreceptor activation to VC may be altered (20,31). During localized cooling in aged skin, the magnitude of the VC response is not diminished but relies more on ROCK and less on other adrenergically stimulated protein kinase signaling cascades (31-33). ROCK can be stimulated by NE or mitochondrial superoxide generated in response to localized cooling (2, 28). Activated ROCK elicits VC through two distinct mec...

Chronic systemic platelet cyclooxygenase (COX) inhibition with low-dose aspirin [acetylsalicylic acid (ASA)] significantly attenuates reflex cutaneous vasodilation in middle-aged humans, whereas acute, localized, nonisoform-specific inhibition of vascular COX with intradermal administration of ketorolac does not alter skin blood flow during hyperthermia. Taken together, these data suggest that platelets may be involved in reflex cutaneous vasodilation, and this response is inhibited with systemic pharmacological platelet inhibition. We hypothesized that, similar to ASA, specific platelet ADP receptor inhibition with clopidogrel would attenuate reflex vasodilation in middle-aged skin. In a double-blind crossover design, 10 subjects (53+/-2 yr) were instrumented with four microdialysis fibers for localized drug administration and heated to increase body core temperature [oral temperature (Tor)] 1 degrees C during no systemic drug (ND), and after 7 days of systemic ASA (81 mg) and clopidogrel (75 mg) treatment. Skin blood flow (SkBF) was measured using laser-Doppler flowmetry over each site assigned as 1) control, 2) nitric oxide synthase inhibited (NOS-I; 10 mM NG-nitro-L-arginine methyl ester), 3) COX inhibited (COX-I; 10 mM ketorolac), and 4) NOS-I+COX-I. Data were normalized and presented as a percentage of maximal cutaneous vascular conductance (%CVCmax; 28 mM sodium nitroprusside+local heating to 43 degrees C). During ND conditions, SkBF with change (Delta) in Tor=1.0 degrees C was 56+/-3% CVCmax. Systemic low-dose ASA and clopidogrel both attenuated reflex vasodilation (ASA: 43+/-3; clopidogrel: 32+/-3% CVCmax; both P<0.001). In all trials, localized COX-I did not alter SkBF during significant hyperthermia (ND: 56+/-7; ASA: 43+/-5; clopidogrel: 35+/-5% CVCmax; all P>0.05). NOS-I attenuated vasodilation in ND and ASA (ND: 28+/-6; ASA: 25+/-4% CVCmax; both P<0.001), but not with clopidogrel (27+/-4% CVCmax; P>0.05). NOS-I+COX-I was not different compared with NOS-I alone in either systemic treatment condition. Both systemic ASA and clopidogrel reduced the time required to increase Tor 1 degrees C (ND: 58+/-3 vs. ASA: 45+/-2; clopidogrel: 39+/-2 min; both P<0.001). ASA-induced COX and specific platelet ADP receptor inhibition attenuate reflex vasodilation, suggesting platelet involvement in reflex vasodilation through the release of vasodilating factors.

Septic arthritis of the wrist can result in permanent damage to the joint, making timely diagnosis crucial to initiate empiric antibiotics and surgical intervention. Although septic arthritis is routinely included in the differential diagnosis of atraumatic wrist pain, the incidence is unknown. Unlike large joints, there is no consensus on cell count values considered pathognomonic for wrist septic arthritis. The goal of this retrospective study was to determine the incidence of wrist septic arthritis and to identify the clinical, serum, and joint fluid values that predict infection. The records of patients who presented to a single urban hospital with a swollen, painful wrist without trauma during a 10-year period were reviewed. For patients who had a joint fluid analysis, the records were examined for history as well as demographic and laboratory data. Joint fluid analysis consisted of cell count, Gram stain, and cultures. Of 892 patients who met the inclusion criteria, 1.5% had wrist septic arthritis. Variables associated with septic arthritis included serum white blood cell count above 11,000/µL, core temperature above 100.4°F within 24 hours of aspiration, history of intravenous drug abuse, and smoking. No joint cell count analysis predicted septic arthritis, although patients with septic wrists had an elevated joint white blood cell count above 97,000/µL. Wrist septic arthritis is uncommon; however, objective factors can help identify patients at risk. Because joint cell count analysis cannot reliably predict a septic wrist, priority for joint aspirations with limited fluid should be given instead to Gram stain, culture, and crystal analysis. [Orthopedics. 2017; 40(3):e526-e531.].

The goal of this retrospective review was to determine whether fluoroscopic guidance improves acetabular cup abduction and anteversion alignment during anterior total hip arthroplasty. The authors retrospectively reviewed 199 patients (fluoroscopy group, 98; nonfluoroscopy group, 101) who underwent anterior total hip arthroplasty at a single center with and without C-arm fluoroscopy guidance. Included in the study were patients of any age who underwent primary anterior approach total hip arthroplasty performed by a single surgeon, with 6-month postoperative anteroposterior pelvis radiographs. Acetabular cup abduction and anteversion angles were measured and compared between groups. Mean acetabular cup abduction and anteversion angles were 43.4° (range, 26.0°-57.4°) and 23.1° (range, 17°-28°), respectively, in the fluoroscopy group. Mean abduction and anteversion angles were 45.9° (range, 29.7°-61.3°) and 23.1° (range, 17°-28°), respectively, after anterior total hip arthroplasty without the use of C-arm guidance (nonfluoroscopy group). The use of fluoroscopy was associated with a statistically significant difference in cup abduction (P=.002) but no statistically significant difference in anteversion angles. In the fluoroscopy group, 80% of implants were within the combined safe zone compared with 63% in the nonfluoroscopy group. A significantly higher percentage of both acetabular cup abduction angles and combined anteversion and abduction angles were in the safe zone in the fluoroscopy group. Fluoroscopy is not required for proper anteversion placement of acetabular components, but it may increase ideal safe zone placement of components.