The Use of Silver Oxynitrate Wound Dressings in the Treatment of Chronic Wounds: A Feasibility Pilot Study.

OBJECTIVE: To evaluate the feasibility and effectiveness of a silver oxynitrate (Ag 7 NO 11 ) dressing on wound healing in patients with stalled chronic wounds. METHODS: A prospective pilot study was conducted to determine the feasibility and effect of using silver oxynitrate dressings within an outpatient setting in Alberta, Canada. A total of 23 patients (12 women and 11 men; mean age, 66.1 ± 13.8 years) with a chronic wound that failed to heal with conventional treatment were included in the study. Wound assessments including the Bates-Jensen Wound Assessment Tool, wound-related pain, wound size, and patient quality of life (QoL) were conducted at baseline, after dressing application for 1 and 2 weeks, and during 4- and 12-week follow-ups. RESULTS: Dressing application at 1 and 2 weeks improved patients' wound healing progression as measured through significantly decreased Bates-Jensen Wound Assessment Tool scores with a more than 10% decrease at 4- and 12-week follow-up ( P < .001). Pain ( P = .004), and QoL psyche subscore ( P = .008) significantly improved at 4-week follow-ups, although wound area, perimeter, and QoL body and everyday subscores were not significantly affected. Wound size was not significantly affected. CONCLUSIONS: The silver oxynitrate dressing may improve healing progression in patients with chronic wounds, enhance patient experience by reducing wound-related pain, and improve patients' mental well-being. Further studies are warranted to elucidate the effect of silver oxynitrate dressings on wound area, perimeter, and volume measurements.

A Scoping Review of the Use of Silver-impregnated Dressings for the Treatment of Chronic Wounds.

Topical silver agents and dressings are used to control infection and promote healing in chronic wounds, but reviews published from 2006 to 2011 found heterogeneous results regarding their effectiveness. A scoping review was conducted to examine the extent, range, and nature of research activity surrounding chronic wound care that employed silver-impregnated dressings; identify research gaps in the existing literature; and summarize the evidence to provide recommendations for future clinical studies. Ten (10) electronic databases and additional sources were screened from their inception to May 2016; search terms for the different databases included but were not limited to silver, chronic, complications, wound, ulcer, and sore. English-language articles that compared silver dressings with an alternate treatment in adults with chronic wounds and that reported clinical outcome measures were included. Of 222 full-text reviewed studies, 27 were included for qualitative analysis. Qualitative analysis was guided by key findings identified among the included studies that were analyzed in aggregate form where appropriate. In comparative analyses of the 26 studies that investigated wound healing, 15 revealed significantly positive wound healing outcomes with silver treatments versus 9 that did not; the remaining 2 failed to provide statistical values of significance. Of 17 studies that presented data on microbiology, 3 reported significant microbial load improvement for silver dressings, 9 noted nonsignificant findings, and 4 provided no statistical values. Pain, adverse events, and treatment cost were included in 5, 7, and 3 studies, respectively, with heterogeneous findings. The heterogeneous evidence regarding the impact of silver dressings on clinical outcomes may be related to differences in the silver treatments themselves, heterogeneous intervention strategies, study designs, outcomes, and measures. Well-designed clinical studies with multiple outcome parameters are necessary to determine the optimal type and use of silver-dressings in chronic wounds.

Older adults show higher increases in lower-limb muscle activity during whole-body vibration exercise.

The purpose of this study was to compare lower limb muscle activity during whole-body vibration (WBV) exercise between a young and an older study population. Thirty young (25.9±4.3yrs) and thirty older (64.2±5.3yrs) individuals stood on a side-alternating WBV platform while surface electromyography (sEMG) was measured for the tibialis anterior (TA), gastrocnemius medialis (GM), soleus (SOL), vastus lateralis (VL), vastus medialis (VM), and biceps femoris (BF). The WBV protocol included nine vibration settings consisting of three frequencies (6, 11, 16Hz) x three amplitudes (0.9, 2.5, 4.0mm), and three control trials without vibration (narrow, medium, wide stance). The vertical platform acceleration (peak values of maximal displacement from equilibrium) was quantified during each vibration exercise using an accelerometer. The outcomes of this study showed that WBV significantly increased muscle activity in both groups for most vibration conditions in the TA (averaged absolute increase: young: +3.9%, older: +18.4%), GM (young: +4.1%, older: +9.5%), VL (young: +6.3%, older: +12.6%) and VM (young: +5.4%, older: +8.0%), and for the high frequency-amplitude combinations in the SOL (young: +7.5%, older: +12.6%) and BF (young: +1.9%, older: +7.5%). The increases in sEMG activity were significantly higher in the older than the young adults for all muscles, i.e., TA (absolute difference: 13.8%, P<0.001), GM (4.6%, P=0.034), VL (7.6%, P=0.001), VM (6.7%, P=0.042), BF (6.4%, P<0.001), except for the SOL (0.3%, P=0.248). Finally, the vertical platform acceleration was a significant predictor of the averaged lower limb muscle activity in the young (r=0.917, P<0.001) and older adults (r=0.931, P<0.001). In conclusion, the older population showed greater increases in lower limb muscle activity during WBV exercise than their young counterparts, meaning that they might benefit more from WBV exercises. Additionally, training intensity can be increased by increasing the vertical acceleration load.

Comparison of sEMG processing methods during whole-body vibration exercise.

The objective was to investigate the influence of surface electromyography (sEMG) processing methods on the quantification of muscle activity during whole-body vibration (WBV) exercises. sEMG activity was recorded while the participants performed squats on the platform with and without WBV. The spikes observed in the sEMG spectrum at the vibration frequency and its harmonics were deleted using state-of-the-art methods, i.e. (1) a band-stop filter, (2) a band-pass filter, and (3) spectral linear interpolation. The same filtering methods were applied on the sEMG during the no-vibration trial. The linear interpolation method showed the highest intraclass correlation coefficients (no vibration: 0.999, WBV: 0.757-0.979) with the comparison measure (unfiltered sEMG during the no-vibration trial), followed by the band-stop filter (no vibration: 0.929-0.975, WBV: 0.661-0.938). While both methods introduced a systematic bias (P < 0.001), the error increased with increasing mean values to a higher degree for the band-stop filter. After adjusting the sEMG(RMS) during WBV for the bias, the performance of the interpolation method and the band-stop filter was comparable. The band-pass filter was in poor agreement with the other methods (ICC: 0.207-0.697), unless the sEMG(RMS) was corrected for the bias (ICC ⩾ 0.931, %LOA ⩽ 32.3). In conclusion, spectral linear interpolation or a band-stop filter centered at the vibration frequency and its multiple harmonics should be applied to delete the artifacts in the sEMG signals during WBV. With the use of a band-stop filter it is recommended to correct the sEMG(RMS) for the bias as this procedure improved its performance.

sEMG during Whole-Body Vibration Contains Motion Artifacts and Reflex Activity.

The purpose of this study was to determine whether the excessive spikes observed in the surface electromyography (sEMG) spectrum recorded during whole-body vibration (WBV) exercises contain motion artifacts and/or reflex activity. The occurrence of motion artifacts was tested by electrical recordings of the patella. The involvement of reflex activity was investigated by analyzing the magnitude of the isolated spikes during changes in voluntary background muscle activity. Eighteen physically active volunteers performed static squats while the sEMG was measured of five lower limb muscles during vertical WBV using no load and an additional load of 33 kg. In order to record motion artifacts during WBV, a pair of electrodes was positioned on the patella with several layers of tape between skin and electrodes. Spectral analysis of the patella signal revealed recordings of motion artifacts as high peaks at the vibration frequency (fundamental) and marginal peaks at the multiple harmonics were observed. For the sEMG recordings, the root mean square of the spikes increased with increasing additional loads (p < 0.05), and was significantly correlated to the sEMG signal without the spikes of the respective muscle (r range: 0.54 - 0.92, p < 0.05). This finding indicates that reflex activity might be contained in the isolated spikes, as identical behavior has been found for stretch reflex responses evoked during direct vibration. In conclusion, the spikes visible in the sEMG spectrum during WBV exercises contain motion artifacts and possibly reflex activity. Key pointsThe spikes observed in the sEMG spectrum during WBV exercises contain motion artifacts and possibly reflex activityThe motion artifacts are more pronounced in the first spike than the following spikes in the sEMG spectrumReflex activity during WBV exercises is enhanced with an additional load of approximately 50% of the body mass.

Relationship Between Lower Limb Muscle Activity and Platform Acceleration During Whole-Body Vibration Exercise.

The purpose of this study was to identify the influence of different magnitudes and directions of the vibration platform acceleration on surface electromyography (sEMG) during whole-body vibration (WBV) exercises. Therefore, a WBV platform was used that delivers vertical vibrations by a side-alternating mode, horizontal vibrations by a circular mode, and vibrations in all 3 planes by a dual mode. Surface electromyography signals of selected lower limb muscles were measured in 30 individuals while they performed a static squat on a vibration platform. The WBV trials included 2 side-alternating trials (Side-L: 6 Hz, 2.5 mm; Side-H: 16 Hz, 4 mm), 2 circular trials (Circ-L: 14 Hz, 0.8 mm; Circ-H: 43 Hz, 0.8 mm), and 4 dual-mode trials that were the combinations of the single-mode trials (Side-L/Circ-L, Side-L/Circ-H, Side-H/Circ-L, Side-H/Circ-H). Furthermore, control trials without vibration were assessed, and 3-dimensional platform acceleration was quantified during the vibration. Significant increases in the root mean square of the sEMG (sEMGRMS) compared with the control trial were found in most muscles for Side-L/Circ-H (+17 to +63%, p ≤ 0.05), Side-H/Circ-L (+7 to +227%, p ≤ 0.05), and Side-H/Circ-H (+21 to +207%, p < 0.01) and in the lower leg muscles for Side-H (+35 to +138%, p ≤ 0.05). Furthermore, only the vertical platform acceleration showed a linear relationship (r = 0.970, p < 0.001) with the averaged sEMGRMS of the lower limb muscles. Significant increases in sEMGRMS were found with a vertical acceleration threshold of 18 m·s(-2) and higher. The present results emphasize that WBV exercises should be performed on a platform that induces vertical accelerations of 18 m·s(-2) and higher.

Vibration transmission to lower extremity soft tissues during whole-body vibration.

In order to evaluate potential risks of whole-body vibration (WBV) training, it is important to understand the transfer of vibrations from the WBV platform to the muscles. Therefore, the purpose of this study was to quantify the transmissibility of vibrations from the WBV platform to the triceps surae and quadriceps soft tissue compartments. Sixteen healthy, male participants were exposed to side-altering WBV at 2.5mm amplitude and frequencies of 10, 17 and 28 Hz. Acceleration signals were measured at the platform and at the soft tissue compartments using tri-axial accelerometers. Transmissibility of peak acceleration and peak amplitude for both tested soft tissue compartments was high at 10 Hz (2.1-2.3), moderate at 17 Hz (1.1-1.9) and low at 28 Hz (0.5-1.2). The average peak acceleration was 125.4 ms(-2) and 46.5 ms(-2) for the triceps surae and quadriceps at 28 Hz, respectively. The muscles' vibration frequency was equal to the input frequency of the WBV platform (p<0.05). The transfer of vibrations to the muscles is strongly dependent on the platform frequency and the particular muscle of interest. The acceleration measured at the triceps surae was higher than the corresponding accelerations related to soft tissue injury in animal studies but neither existing regulations nor the comparison to available animal studies seem appropriate to make inferences on injury risk. More realistic animal or computational muscle models may use the current data to evaluate potentially unwanted side effects of WBV training.

Determination of the optimal parameters maximizing muscle activity of the lower limbs during vertical synchronous whole-body vibration.

PURPOSE: To describe the most effective parameters maximizing muscle activity during whole-body vibration (WBV) exercises on a vertically vibrating (VV) platform. METHODS: The influence of (1) WBV vs. no vibration, (2) vibration frequency (25, 30, 35, 40 Hz), (3) platform peak-to-peak displacement (1.2, 2 mm), and (4) additional loading (no load, 17, 33 kg) on surface electromyographic (sEMG) activity of five lower limb muscles was investigated in eighteen participants. RESULTS: (1) Comparing WBV to no vibration, sEMGRMS of the calf muscles was significantly higher with an additional load of 33 kg independently of the displacement and the frequency (P < 0.05). During WBV, (2) muscle activity at 40 Hz WBV was significantly higher than at 25 Hz for the gastrocnemius lateralis (GL) for all loads, and for the vastii medialis and lateralis using the 33 kg load (P < 0.05); (3) sEMGRMS of all lower limb muscles was significantly increased with the 2 mm compared to the 1.2 mm peak-to-peak displacement (P < 0.05); (4) an effect of additional load was found in the GL, with significantly higher neuromuscular activation for the 33 kg load than no load (P < 0.05). CONCLUSIONS: On a VV platform, we recommend the use of a high platform displacement in combination with a high vibration frequency to provoke the highest muscle activity enhancement. Without maxing out the acceleration stimuli, calf muscles' sEMG can be enhanced with an additional load of 33 kg which corresponded to 50 % of the body mass.

Validity of the Optogait photoelectric system for the assessment of spatiotemporal gait parameters.

The purpose of this study was to evaluate the discriminant and concurrent (criterion-related) validity of a recently introduced floor-based photocell system (Optogait, Microgate, Bolzano, Italy) with a validated electronic walkway for the assessment of spatiotemporal gait parameters. Fifteen patients (mean age±standard deviation: 65±7 years) with total knee arthroplasty and 15 healthy matched control subjects were asked to walk at different velocities while gait variables were recorded simultaneously by the two instruments. The Optogait and the criterion instrument detected the same differences in walking parameters between patients and controls. Intraclass correlation coefficients ranged between 0.933 (swing time) and 0.999 (cycle time, cadence and walking speed). Cycle time and stance time were significantly longer, while swing time, step length, cadence and walking speed were significantly lower for Optogait (p<0.001) compared to the criterion instrument. The Optogait system demonstrated high discriminant and concurrent validity with an electronic walkway for the assessment of spatiotemporal gait parameters in orthopedic patients and healthy controls. However, the two measuring instruments cannot be used interchangeably for quantitative gait analysis, and further validation of floor-based photocell technology is warranted.