Poly(N-isopropylacrylamide) based smart nanofibrous scaffolds for use as on-demand delivery systems for oral and dental tissue regeneration

Stimuli-responsive domains capable of releasing loaded molecules, "on-demand," have garnered increasing attention due to their enhanced delivery, precision targeting, and decreased adverse effects. The development of an on-demand delivery system that can be easily triggered by dental clinicians might have major roles in dental and oral tissue engineering. A series of random graft poly(NIPAm-co-HEMA-Lactate) copolymers were synthesized using 95:5, 85:5, 60:40, and 40:60 ratios of thermosensitive NIPAm and HEMA-poly lactate respectively then electrospun to produce nanofibrous scaffolds loaded with bovine serum albumin (BSA). Cumulative BSA release was assessed at 25C and 37°C. To appraise the use of scaffolds as on-demand delivery systems, they were subjected to thermal changes in the form cooling and warming cycles during which BSA release was monitored. To confirm the triggered releasing ability of the synthesized scaffolds, the copolymer made with 60% NIPAm was selected, based on the results of the release tests, and loaded with bone morphogenetic protein-2 (BMP-2). The loaded scaffolds were placed with mesenchymal-like stem cells (iMSCs) derived from induced pluripotent stem cells (iPSCs), and subjected to temperature alterations. Then, the osteogenic differentiation of iMSCs, which might have resulted from the released protein, was evaluated after 10 days by analyzing runt-related transcription factor 2 (RUNX-2) osteogenic gene expression by the cells using real-time quantitative polymerase chain reaction (qRT-PCR). BSA release profiles showed a burst release at the beginning followed by a more linear pattern at 25°C, and a much slower release at 37°C. The release also decreased when the PNIPAm content decreased in the scaffolds. Thermal triggering led to a step-like release pattern in which the highest release was reported 30 min through the warming cycles. The iMSCs cultivated with scaffolds loaded with BMP-2 and exposed to temperature alteration showed significantly higher RUNX-2 gene expression than cells in the other experimental groups. The synthesized scaffolds are thermo-responsive and could be triggered to deliver biological biomolecules to be used in oral and dental tissue engineering. Thermal stimuli could be simulated by dental clinicians using simple means of cold therapy, for example, cold packs in intraoral accessible sites for specified times.

Whole-Body Cryostimulation in Multiple Sclerosis: A Scoping Review

Multiple sclerosis (MS) is the most common cause of non-traumatic long-term disability in young adults. Whole-body cryostimulation (WBC) is a cold-based physical therapy known to induce physiological exercise-mimicking changes in the cardiovascular, neuromuscular, immune, and endocrine systems and to influence functional and psychological parameters by exposing the human body to cryogenic temperatures (≤-110 °C) for 2-3 min. The purpose of this scoping review is to present an overall view on the potential role of WBC as an adjuvant therapy in the treatment of MS. PubMed, ScienceDirect, Embase, and Web of Science were searched up to 30 November 2023, and a total of 13 articles were included. WBC may have beneficial antioxidant effects as a short-term adjuvant treatment in MS. There were no significant changes in antioxidant enzymes, nitric oxide levels, metalloproteinase levels, blood counts, rheology, and biochemistry. WBC can lead to a reduction in fatigue and an improvement in functional status, with a significant effect on both mental and physical well-being. There were no reported adverse effects. The results suggest that WBC may complement therapeutic options for patients with MS, as the effects of cryogenic cold stimulation have been shown to activate antioxidant processes and improve functional status, mood, anxiety, and fatigue.

Cryotherapy in Postoperative Shoulder Surgery: A Systematic Review

Cryotherapy, a therapeutic technique involving localized cooling of the body, has gained popularity for postsurgical rehabilitation. It induces a reduction in cellular metabolism, vasoconstriction, and pain relief, making it an attractive option for managing postoperative (PO) shoulder pain. This systematic review aimed to assess the effectiveness of cryotherapy in PO shoulder patients, focusing on pain, range of motion, functionality, and temperature changes. The review included six randomized clinical trials, involving a total of 233 patients who underwent various shoulder surgeries. Cryotherapy was applied using different methods, including Cryo/Cuff, Cryoton®, Polar Care 300, and ice packs. Results indicated that cryotherapy was generally effective in reducing PO shoulder pain. However, one study found no significant difference in pain outcomes between the cryotherapy group and control group. Furthermore, three studies demonstrated a decrease in intra-articular and skin temperatures with cryotherapy application. A risk of bias analysis revealed some concerns in the overall risk of bias for five studies, with one study considered to have a high risk of bias. Although publication bias assessment was not conducted due to the limited number of included studies, it was noted that the studies exhibited heterogeneity in terms of population, intervention methods, and outcome measures. In conclusion, cryotherapy appears to be a promising adjunctive treatment for PO shoulder pain, although the existing evidence has some limitations, including small sample sizes and methodological concerns. More high-quality studies are needed to establish the full extent of cryotherapy's effectiveness in PO shoulder rehabilitation, especially regarding its impact on functionality and range of motion.

The effectiveness and safety of heat/cold therapy in adults with lymphoedema: systematic review

PURPOSE

The aim of this review is to assess the efficacy and safety of using heat and cold therapy for adults with lymphoedema.

METHODS

A multi-database search was undertaken. Only studies which included adults with lymphoedema who were treated with heat or cold therapy reporting any outcome were included. Screening, data extraction, and assessment of bias were undertaken by a single reviewer and verified by a second. Due to the substantial heterogeneity, a descriptive synthesis was undertaken.

RESULTS

Eighteen studies were included. All nine studies which assessed the effects of heat-therapy on changes in limb circumference reported a point estimate indicating some reduction from baseline to end of study. Similarly, the five studies evaluating the use of heat-therapy on limb volume demonstrated a reduction in limb volume from baseline to end-of-study. Only four studies reported adverse events of which all were deemed to be minor. Only two studies explored the effects of cold therapy on lymphoedema.

CONCLUSIONS

Tentative evidence suggests heat-therapy may have some benefit in treating lymphoedema with minimal side effects. However, further high-quality randomised controlled trials are required, with a particular focus on moderating factors and assessment of adverse events.

Comparative Effectiveness of Gua Sha, Cryostretch, and Positional Release Technique on Tenderness and Function in Subjects with Plantar Fasciitis: a Randomized Clinical Trial

Background

Plantar fasciitis (PF) can be treated effectively with manual techniques like cryostretch (CS) and the positional release technique (PRT). Although Gua Sha (GS) has been suggested in the literature for PF, its efficacy has not been studied in the research.

Objective

To determine and compare the effectiveness of GS, CS, and PRT in subjects with PF in terms of pain intensity, pain pressure threshold, and foot function.

Methods/Design

Thirty-six patients with PF (n=36) were randomly allocated to three study groups (12 in each group)-group GS, group CS, and group PRT, respectively.

Settings

A randomized clinical trial was conducted at physiotherapy OPD in a tertiary health center.

Participants

Subjects of all genders with plantar fasciitis of the age group 20-60 years. Thirty-six subjects with plantar fasciitis out of whom 12 were males and 24 females. There were no dropouts in this study.

Intervention

The interventions included the Gua Sha technique (1 session), the cryostretch technique with a frozen tennis ball (3 sessions), and the positional release technique (7 sessions), along with common exercises for all three groups.

Outcome Measures

Pain intensity, foot functions, and pain pressure threshold were assessed using the Numerical Pain Rating Scale, Foot Function Index, and pressure algometer, respectively, on day 1 (pre-intervention) and day 7 (post-intervention).

Results

Between-group analyses showed that group GS was more effective than CS and PRT for pain (p=.0001), group CS was more effective than GS and PRT for foot function (p=.0001) whereas group PRT was more effective than GS and CS for pain pressure threshold (p=.0001).

Conclusion

Although all three groups showed improvement, Gua Sha was superior in terms of reducing pain, cryostretch for improving foot functions, and PRT for reducing tenderness. The interventions used in this study are cost-effective and have proved to be simple and safe techniques.

Cryotherapy in Anterior Cruciate Ligamentoplasty Pain: A Scoping Review

Cryotherapy is used in individuals in the postoperative period (PO) of anterior cruciate ligament (ACL) repair, owing to its effects such as increased pain threshold, decreased cellular activity, and vasoconstriction. The aim of this study was to analyze the effect of cryotherapy on pain intensity in the immediate PO of ACL reconstruction. A scoping review was performed in the databases: Cochrane, Embase, Lilacs, LIVIVO, PEDro, PubMed, Scopus, and Web of Science; and gray literature: Google Scholar, CAPES Thesis Database, and Open Grey. PRISMA recommendation was followed. Two blinded reviewers performed the selection of studies: Phase 1-reading of titles and abstracts and Phase 2-Reading of the full texts and disagreements resolved in consensus. The references of 701 studies were identified, 603 from the main databases and 98 from the gray literature. After removal of duplicates, 387 studies were left for Phase 1-reading of titles and abstracts according to eligibility criteria and for Phase 2-28 studies for reading of full texts. Two studies were excluded: one randomized clinical trial and another sandwich study. Finally, 15 studies were included in this review. Cryotherapy is effective in reducing pain intensity because there were reductions in the scores of subjective pain scales in the immediate PO of ACL reconstruction. Cryocompression was shown to be superior to conventional cryotherapy.

Cryostimulation for Post-exercise Recovery in Athletes: A Consensus and Position Paper

Recovery after exercise is a crucial key in preventing muscle injuries and in speeding up the processes to return to homeostasis level. There are several ways of developing a recovery strategy with the use of different kinds of traditional and up-to-date techniques. The use of cold has traditionally been used after physical exercise for recovery purposes. In recent years, the use of whole-body cryotherapy/cryostimulation (WBC; an extreme cold stimulation lasting 1-4 min and given in a cold room at a temperature comprised from -60 to -195°C) has been tremendously increased for such purposes. However, there are controversies about the benefits that the use of this technique may provide. Therefore, the main objectives of this paper are to describe what is whole body cryotherapy/cryostimulation, review and debate the benefits that its use may provide, present practical considerations and applications, and emphasize the need of customization depending on the context, the purpose, and the subject's characteristics. This review is written by international experts from the working group on WBC from the International Institute of Refrigeration.

Is Intracanal Cryotherapy Effective in Reducing Postoperative Endodontic Pain? An Updated Systematic Review and Meta-Analysis of Randomized Clinical Trials

This research aimed to assess the potency of intracanal cold therapy in diminishing postoperative endodontic pain. PubMed, Scopus, the Cochrane Library, EMBASE, the Web of Science, grey literature, and endodontic journals were used to identify randomized controlled clinical trials evaluating postoperative pain after a final irrigation with a cold irrigant (as an experimental group) and a room temperature irrigant (as a control group). The risk of bias was rated according to the Cochrane Collaboration's tool and the Grading Recommendation Assessment, Development, and Evaluation (GRADE) system was used to estimate the evidence quality. For the meta-analysis, a random effects model was utilized. The qualitative analysis contained 16 studies and the quantitative analysis contained 9 studies. The experimental groups showed a reduction in postoperative pain at 6 h (mean difference (MD) = -1.11; p = 0.0004; I2 = 72%; low quality evidence), 24 h (MD = -1.08; p = 0.003; I2 = 92%; low quality evidence), 48 h (MD = -0.38; p = 0.04; I2 = 81%; low quality evidence), and 72 h (MD = -0.69; p = 0.04; I2 = 90%; low quality evidence). A higher quality of evidence from more clinical trials is needed.

A Randomised Controlled Trial of Ice to Reduce the Pain of Immunisation-The ICE Trial

Background and objectives: vaccine injections are a common cause of iatrogenic pain and anxiety, contributing to non-compliance with scheduled vaccinations. With injection-related pain being recognised as a barrier to vaccination uptake in both adults and children, it is important to investigate strategies to effectively reduce immunisation pain. This prospective randomised controlled trial investigated the effects of applying an ice pack on vaccine-related pain in adults. Methods: medical students receiving the flu vaccination were randomised to receive an ice pack (intervention) or placebo cold pack (control) at the injection site for 30 s prior to needle insertion. Immediate post-vaccination pain (VAS) and adverse reactions in the proceeding 24 h were recorded. Results: pain scores between the intervention (n = 19) and control groups (n = 16) were not statistically significant (intervention: median pain VAS = 7.00, IQR = 18; control: median pain VAS = 11, IQR = 14 (p = 0.26). There were no significant differences in the number of adverse events between the two groups (site pain p = 0.18; localised swelling (p = 0.67); bruising p = 0.09; erythema p = 0.46). Discussion: ice did not reduce vaccination-related pain compared to cold packs. COVID-19 related restrictions impacted participant recruitment, rendering the study insufficiently powered to draw conclusions about the results.

Changes in the Allostatic Response to Whole-Body Cryotherapy and Static-Stretching Exercises in Chronic Fatigue Syndrome Patients vs. Healthy Individuals

This study represents a comparison of the functional interrelation of fatigue and cognitive, cardiovascular and autonomic nervous systems in a group of Chronic Fatigue Syndrome (CFS) patients compared with those in healthy individuals at different stages of analysis: at baseline and after changes induced by whole-body cryotherapy (WBC) combined with a static-stretching (SS) program. The study included 32 patients (Fukuda criteria) and 18 healthy controls. Fatigue, cognitive, cardiovascular and autonomic function and arterial stiffness were measured before and after 10 sessions of WBC with SS. In the patients, a disturbance in homeostasis was observed. The network relationship based on differences before and after intervention showed comparatively higher stress and eccentricity in the CFS group: 50.9 ± 56.1 vs. 6.35 ± 8.72, p = 0.002, r = 0.28; and 4.8 ± 0.7 vs. 2.4 ± 1, p < 0.001, r = 0.46, respectively. Before and after intervention, in the CFS group increased fatigue was related to baroreceptor function, and baroreceptor function was in turn related to aortic stiffness, but no such relationships were observed in the control group. Differences in the network structure underlying the interrelation among the four measured criteria were observed in both groups, before the intervention and after ten sessions of whole cryotherapy with a static stretching exercise.

Partial-Body Cryostimulation Increases Resting Energy Expenditure in Lean and Obese Women

Cryostimulation is currently seen as a potential adjuvant strategy to tackle obesity and dysmetabolism by triggering cold-induced thermogenesis. Although suggestive, the underlying mechanisms are still poorly elucidated. We tested whether single or repeated applications of partial-body cryostimulation (PBC) could influence resting energy expenditure (REE) in exposed individuals. Fifteen middle-aged obese and sixteen control lean women (body mass index 31 ± 1.6 kg/m² and 22 ± 1.7 kg/m²) underwent a daily PBC (−130 °C × 150 s) for five consecutive days. Resting energy metabolism (REE) was assessed by indirect calorimetry pre- and post-PBC on day 1 and day 5. As concerns REE, the linear mixed model revealed that REE changes were explained by session and time (F_1,29 = 5.58; p = 0.02; ƞ_p² = 0.16) independent of the group (F_1,29 = 2.9; p = 0.09; ƞ_p² = 0.09). REE pre-PBC increased from day 1 to day 5 either in leans (by 8.2%, from 1538 ± 111 to 1665 ± 106 kcal/day) or in obese women (by 5.5%, from 1610 ± 110 to 1698 ± 142 vs kcal/day). Respiratory quotient was significantly affected by the time (F_1,29 = 51.61; p < 0.000001, ƞ_p² = 0.64), as it increased from pre- to post-PBC, suggesting a shift in substrate oxidation. According to these preliminary data, cold-induced thermogenesis could be explored as a strategy to elevate REE in obese subjects. Longitudinal studies could test whether chronic PBC effects may entail favorable metabolic adaptations.

The effects of Mulligan's mobilization with movement technique in patients with lateral epicondylitis

BACKGROUND

Lateral epicondylitis (LE) is a common problem of the arm. Mulligan has proposed the use of mobilization with movement for LE.

OBJECTIVES

To investigate the effects of Mulligan's mobilization with movement (MWM) in LE.

METHODS

Forty patients were included in the study and randomly assigned to group 1 (n= 20), who received MWM, exercise and cold therapy, or group 2 (n= 20), who received exercise and cold therapy. The sessions were conducted five times a week for two weeks. All measures were conducted at baseline, after treatment, at 1st and 3rd months follow-ups. Mann-Whitney U test, a visual analogue scale (VAS) for pain intensity, Patient-rated Tennis Elbow Evaluation (PRTEE) Questionnaire for pain intensity and functional disability and a dynamometer for hand grip strength were applied.

RESULTS

VAS activity pain significantly decreased in group 1 after treatment (p= 0.001), at the 1st (p< 0.001) and 3rd months (p= 0.040). There was a significant decrease in VAS night pain in group 1 (p= 0.024), and a significant increase in pain-free grip strength (p= 0.002) after treatment. PRTEE-Pain scores decreased in group 1 after treatment (p< 0.001), 1st (p< 0.001) and 3rd months (p= 0.001).

CONCLUSIONS

MWM plus exercise and cold therapy is a safe and effective alternative with positive effects on elbow pain, functional capacity, and pain-free, maximum grip strength.

No Effect of Partial-Body Cryotherapy on Restoration of Countermovement Jump or Well-Being Performance in Elite Rugby Union Players During the Competitive Phase of the Season

PURPOSE

Partial body cryotherapy (PBC) has been shown to be beneficial for postexercise recovery; however, no study has demonstrated the effectiveness of PBC for recovery following elite rugby union training. Rugby union is a unique sport that involves high-velocity collisions and may induce greater performance decrements than other sports; thus, PBC could be beneficial. The application of PBC in "real world" has rarely been investigated during the competitive phase of a playing season and warranted investigation.

METHODS

In a counterbalanced sequential research design, professional rugby athletes (n = 18; age 25.4 [4.0] y; training age 7.2 [4.0] y; mass 99.8 [10.6] kg; height 188.3 [6.0] cm) were assigned to a 12-week PBC intervention, washout period (4 wk), and reassessed as their own controls. Self-reported well-being, muscle soreness, sleep quality, and countermovement jump height were assessed before and 40 hours after "real-world" training. Wilcoxon signed-rank tests and Cohen d were used for statistical analysis.

RESULTS

No differences were observed between PBC and control conditions (P > .05; d = 0.00-0.14) for well-being (-0.02% [0.08%] vs 0.01% [0.06%]), muscle soreness (-0.01% [0.11%] vs 0.01% [0.16%]), sleep quality (-0.03% [0.14%] vs 0.10% [0.29%]), or countermovement jump height (36.48-36.59 vs 38.13-37.52 cm; P = .54).

CONCLUSIONS

These results suggest PBC is ineffective for the restoration of selected performance parameters during the performance maintenance phase of the competitive season. To ascertain the appropriation of its use, future investigations should seek to assess the use of cryotherapies at various phases of the elite rugby union competitive season.

Exploring the Efficacy of a Safe Cryotherapy Alternative: Physiological Temperature Changes From Cold-Water Immersion Versus Prolonged Cooling of Phase-Change Material

PURPOSE

To evaluate the effectiveness between cold-water immersion (CWI) and phase-change-material (PCM) cooling on intramuscular, core, and skin-temperature and cardiovascular responses.

METHODS

In a randomized, crossover design, 11 men completed 15 min of 15°C CWI to the umbilicus and 2-h recovery or 3 h of 15°C PCM covering the quadriceps and 1 h of recovery, separated by 24 h. Vastus lateralis intramuscular temperature at 1 and 3 cm, core and skin temperature, heart-rate variability, and thermal comfort were recorded at baseline and 15-min intervals throughout treatment and recovery.

RESULTS

Intramuscular temperature decreased (P < .001) during and after both treatments. A faster initial effect was observed from 15 min of CWI (Δ: 4.3°C [1.7°C] 1 cm; 5.5°C [2.1°C] 3 cm; P = .01). However, over time (2 h 15 min), greater effects were observed from prolonged PCM treatment (Δ: 4.2°C [1.9°C] 1 cm; 2.2°C [2.2°C] 3 cm; treatment × time, P = .0001). During the first hour of recovery from both treatments, intramuscular temperature was higher from CWI at 1 cm (P = .013) but not 3 cm. Core temperature deceased 0.25° (0.32°) from CWI (P = .001) and 0.28°C (0.27°C) from PCM (P = .0001), whereas heart-rate variability increased during both treatments (P = .001), with no differences between treatments.

CONCLUSIONS

The magnitude of temperature reduction from CWI was comparable with PCM, but intramuscular temperature was decreased for longer during PCM. PCM cooling packs offer an alternative for delivering prolonged cooling whenever application of CWI is impractical while also exerting a central effect on core temperature and heart rate.

Cryotherapy reduces muscle hypertonia, but does not affect lower limb strength or gait kinematics post-stroke: a randomized controlled crossover study

BACKGROUND

Based on the premise that spasticity might affect gait post-stroke, cryotherapy is among the techniques used to temporarily reduce spasticity in neurological patients. This effective technique would enhance muscle performance, and ultimately, functional training, such as walking. However, understanding whether a decrease in spasticity level, if any, would lead to improving muscle performance and gait parameters is not based on evidence and needs to be clarified.

OBJECTIVES

to investigate the immediate effects of cryotherapy, applied to spastic plantarflexor muscles of subjects post-stroke, on tonus level, torque generation capacity of plantarflexors and dorsiflexors, and angular/spatiotemporal gait parameters.

METHODS

Sixteen chronic hemiparetic subjects participated in this randomized controlled crossover study. Cryotherapy (ice pack) or Control (room temperature sand pack) were applied to the calf muscles of the paretic limb. The measurements taken (before and immediately after intervention) were: 1) Tonus according to the Modified Ashworth Scale; 2) Torque assessments were performed using an isokinetic dynamometer; and 3) Spatiotemporal and angular kinematics of the hip, knee, and ankle (flexion/extension), obtained using a tridimensional movement analysis system (Qualisys).

RESULTS

Cryotherapy decreased plantarflexor tonus but did not change muscle torque generation capacity and did not affect spatiotemporal or angular parameters during gait compared to control application. These findings contribute to the evidence-based approach to clinical rehabilitation post-stroke.

CONCLUSIONS

The findings of this study suggest that cryotherapy applied to the calf muscles of subjects with chronic hemiparesis reduces muscle hypertonia but does not improve dorsiflexors and plantarflexors performance and gait parameters.

The Effectiveness of the Cold Therapy (cryotherapy) in the Management of Inflammatory Parameters after Removal of Mandibular Third Molars: A Meta-Analysis

Introduction  Cold therapy (cryotherapy) is a common procedure recommended by dental surgeons after surgical removal of third molars, which is an invasive intervention that often deals with an expressive inflammatory response.

Objective  To investigate whether cryotherapy interferes with clinical outcomes such as pain, edema, and trismus in the postoperative period of mandibular third molar surgeries.

Data Synthesis  An electronic search was conducted in the OVID, PubMed, VHL, Science Direct, Cochrane Library, and Web of Science databases, through March 2018. The eligibility criteria included clinical trials that evaluated the effect of cryotherapy in at least one of the following variables: pain, swelling, and trismus.

Two independent reviewers assessed the studies. The methodological quality of each article was analyzed. The search strategy resulted in 1,088 articles. Following the selection process, 11 studies were included in the systematic review and 4 of them in the meta-analysis. High risk of bias was found in most of the studies according to the Cochrane Handbook assessment. Patients receiving cryotherapy had less edema than patients in the control group at second day follow-up (mean difference [MD]: -0.94; 95%CI [-1.49; -0.39]). There were no statistically significant results when comparing trismus between experimental and control group (MD: 0.43; 95%CI [-0.34;1.20]). There were insufficient available data to support influences in postoperative pain.

Conclusions  Cryotherapy applied on the first day after mandibular third molar removal can manage edema in the patients. Well-designed randomized clinical trials to test the efficacy of cryotherapy after surgical removal of third molars are needed to justify its indication.

The Effectiveness of Photobiomodulation Therapy Versus Cryotherapy for Skeletal Muscle Recovery: A Critically Appraised Topic

Clinical Scenario: Cryotherapy is one of the most commonly used modalities for postexercise muscle recovery despite inconsistencies in the literature validating its effectiveness. With the need to find a more effective modality, photobiomodulation therapy (PBMT) has gained popularity because of recent research demonstrating its ability to accelerate the muscle recovery process. Focused Clinical Question: Is PBMT more effective than cryotherapy at reducing recovery time and decreasing delayed onset muscle soreness after strenuous exercise? Summary of Key Findings: Three moderate- to high-quality double-blinded, randomized, placebo-controlled trials and 2 low- to moderate-quality translational studies performed on rats were included in this critically appraised topic. All 5 studies supported the use of PBMT over cryotherapy as a treatment for postexercise muscle recovery following exercise. PBMT was superior in reducing creatine kinase, inflammation markers, and blood lactate compared with cryotherapy, following strenuous/high intensity aerobic or strength muscular exercise. PBMT was also shown to improve postexercise muscle performance and function more than cryotherapy. Clinical Bottom Line: There is moderate evidence to suggest the use of PBMT over cryotherapy postexercise to enhance muscle recovery in trained and untrained athletes. Shorter recovery times and increased muscle performance can be seen 24 to 96 hours following PBMT application. Strength of Recommendation: Based on consistent findings from all 5 studies, there is grade B evidence to support the use of PBMT over cryotherapy for more effective postexercise recovery of skeletal muscle performance.

Termination of Atrial Fibrillation With Epicardial Cooling in the Oblique Sinus

OBJECTIVES

This study aimed to determine if epicardial cooling could repeatedly terminate induced atrial fibrillation (AF) in a canine heart.

BACKGROUND

Rapid termination of AF could control symptoms and prevent atrial remodeling; however, defibrillation by internal electrical cardioversion is not tolerable to most patients. Cooling of the epicardium slows atrial conduction and may provide a less painful method to quickly terminate AF.

METHODS

AF was induced with atrial myocardial epinephrine injections and rapid atrial pacing in an open-chest canine. Attempts at termination were performed with a small metal device that was either cooled to 5°C or kept at body temperature (control module). The device was placed on the epicardial surface in the oblique sinus. The time from device contact to termination of AF was recorded.

RESULTS

In 5 different canine studies, there were 57 attempts at AF termination with either a 5°C module (34 attempts) or a control module (23 attempts). The median (interquartile range [IQR]) time to AF termination was 24 s (IQR: 15 to 35 s) for the 5°C therapy and 100 s (IQR: 47 to 240 s) for the body temperature treatments (p < 0.001). In the control group, there were 8 AF episodes that continued up to 4 min. Subsequent application of the 5°C cooling module terminated AF in all cases.

CONCLUSIONS

Epicardial cooling in the oblique sinus is effective for repeated termination of AF in a canine heart. If reproduced in human studies, epicardial cooling with an implantable device may provide a method for management of patients with AF.

Effectiveness of cold therapy in reducing pain, trismus, and oedema after impacted mandibular third molar surgery: a randomized, self-controlled, observer-blind, split-mouth clinical trial

Cold therapy is a conventional and widely used modality for reducing pain, trismus, and oedema after dentoalveolar surgeries. However, information reported in the literature on its effectiveness is insufficient and controversial. This study was performed to evaluate the effect of local cold application in reducing pain, trismus, and swelling after impacted mandibular third molar surgery. Thirty patients (seven males and 23 females) with bilateral symmetrical mandibular impacted third molars were enrolled in this randomized, self-controlled, observer-blind clinical trial. The patients were aged between 18 and 30 years. After surgical removal of the tooth on one side (intervention), ice pack therapy was given for 24h after surgery; for the other side (control), no cold therapy was given. The time interval between the two surgeries was at least 4 weeks. The amount of pain, trismus, and facial swelling was measured on days 2 and 7 postoperative, and patient satisfaction with the cold therapy vs. no cold therapy was assessed. The amount of pain, trismus, and facial swelling, and the extent of patient satisfaction were not significantly different between the intervention and control sides. Cold therapy had no beneficial effects on postoperative sequelae after impacted mandibular third molar surgery.

Cold-water immersion decreases cerebral oxygenation but improves recovery after intermittent-sprint exercise in the heat

This study examined the effects of post-exercise cooling on recovery of neuromuscular, physiological, and cerebral hemodynamic responses after intermittent-sprint exercise in the heat. Nine participants underwent three post-exercise recovery trials, including a control (CONT), mixed-method cooling (MIX), and cold-water immersion (10 °C; CWI). Voluntary force and activation were assessed simultaneously with cerebral oxygenation (near-infrared spectroscopy) pre- and post-exercise, post-intervention, and 1-h and 24-h post-exercise. Measures of heart rate, core temperature, skin temperature, muscle damage, and inflammation were also collected. Both cooling interventions reduced heart rate, core, and skin temperature post-intervention (P < 0.05). CWI hastened the recovery of voluntary force by 12.7 ± 11.7% (mean ± SD) and 16.3 ± 10.5% 1-h post-exercise compared to MIX and CONT, respectively (P < 0.01). Voluntary force remained elevated by 16.1 ± 20.5% 24-h post-exercise after CWI compared to CONT (P < 0.05). Central activation was increased post-intervention and 1-h post-exercise with CWI compared to CONT (P < 0.05), without differences between conditions 24-h post-exercise (P > 0.05). CWI reduced cerebral oxygenation compared to MIX and CONT post-intervention (P < 0.01). Furthermore, cooling interventions reduced cortisol 1-h post-exercise (P < 0.01), although only CWI blunted creatine kinase 24-h post-exercise compared to CONT (P < 0.05). Accordingly, improvements in neuromuscular recovery after post-exercise cooling appear to be disassociated with cerebral oxygenation, rather reflecting reductions in thermoregulatory demands to sustain force production.

Influence of Local Cooling on Proprioceptive Acuity in the Quadriceps Muscle

OBJECTIVE: To test the influence of cooling on proprioceptive acuity as reflected in the ability to discriminate weights. DESIGN AND SETTING: Participants were trained to perform a weight-discrimination task. Their ability to correctly report small increments in weight was compared before and after local cooling (a 20-minute application of a crushed-ice pack) of the quadriceps muscle group. Data were collected at a university research laboratory. SUBJECTS: Twenty young, physically active adults (undergraduate students; 14 men, 6 women; mean age, 22.1 +/- 2.6 years). MEASUREMENTS: We calculated overall performance in the weight-discrimination task (percentage of discrimination correct) for each participant to estimate the differential threshold (ie, minimal increment in weight that yields a probability of 75% correct responses). RESULTS: Before local cooling, participants discriminated increments in the order of 4% to 10% from the standard weight (mean threshold, 0.17 +/- 0.06 kg). After local cooling, the discriminative performance remained, on average, very similar to that seen before cooling (mean threshold, 0.17 +/- 0.08 kg; paired t test: t = 0.24, P =.81). Only a small group of participants (n = 5) showed evidence of a decreased ability to discriminate weight after cooling. CONCLUSIONS: The perception of force signals required for weight discrimination does not appear to be affected by local cooling of the quadriceps muscle group. This finding provides additional evidence for the relative safety of cold applications and their effect on proprioceptive perceptual abilities.