Microcirculation of the ankle after Cryo/Cuff application in healthy volunteers

Whole-body cryotherapy as a treatment for chronic medical conditions?

INTRODUCTION

Whole-body cryotherapy (WBC) is a controlled exposure of the whole body to cold to gain health benefits. In recent years, data on potential applications of WBC in multiple clinical settings have emerged.

SOURCES OF DATA

PubMed, EBSCO and Clinical Key search using keywords including terms 'whole body', 'cryotherapy' and 'cryostimulation'.

AREAS OF AGREEMENT

WBC could be applied as adjuvant therapy in multiple conditions involving chronic inflammation because of its potent anti-inflammatory effects. Those might include systemic inflammation as in rheumatoid arthritis. In addition, WBC could serve as adjuvant therapy for chronic inflammation in some patients with obesity.

AREAS OF CONTROVERSY

WBC probably might be applied as an adjuvant treatment in patients with chronic brain disorders including mild cognitive impairment and general anxiety disorder and in patients with depressive episodes and neuroinflammation reduction as in multiple sclerosis. WBC effects in metabolic disorder treatment are yet to be determined. WBC presumably exerts pleiotropic effects and therefore might serve as adjuvant therapy in multi-systemic disorders, including myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

GROWING POINTS

The quality of studies on the effects of WBC in the clinical setting is in general low; hence, randomized controlled trials with adequate sample size and longer follow-up periods are needed.

AREAS ARE TIMELY FOR DEVELOPING RESEARCH

Further studies should examine the mechanism underlying the clinical efficacy of WBC. Multiple conditions might involve chronic inflammation, which in turn could be a potential target of WBC. Further research on the application of WBC in neurodegenerative disorders, neuropsychiatric disorders and ME/CFS should be conducted.

Assessing the effects of Kampo medicine on human skin texture and microcirculation

In this study, we verified the effectiveness of Kampo medicine by evaluating the changes in the feature values of facial skin texture and microcirculation at two distinct tissue depths (subcutaneous 2 mm and 8 mm). A total of 80 patients who took the Kampo formula participated in this study, and the changes in the feature values of facial skin texture and microcirculation were measured before and after Kampo treatment. The treatment period lasted 6–18 months, according to the doctor’s judgment. The total area of the sulci cutis and the average thickness of the sulci cutis significantly decreased (P < 0.05), and the pixels of the grayscale image increased after Kampo treatment (P < 0.05). Moreover, the blood flow velocity at 8 mm depth significantly increased after Kampo treatment (P < 0.05). In this study, we specifically noted changes in the skin texture and microcirculation after Kampo treatment.

Muscle Oxygenation Level Might Trigger the Regulation of Capillary Venous Blood Filling during Fatiguing Isometric Muscle Actions

The regulation of oxygen and blood supply during isometric muscle actions is still unclear. Recently, two behavioral types of oxygen saturation (SvO2) and relative hemoglobin amount (rHb) in venous microvessels were described during a fatiguing holding isometric muscle action (HIMA) (type I: nearly parallel behavior of SvO2 and rHb; type II: partly inverse behavior). The study aimed to ascertain an explanation of these two regulative behaviors. Twelve subjects performed one fatiguing HIMA trial with each arm by weight holding at 60% of the maximal voluntary isometric contraction (MVIC) in a 90° elbow flexion. Six subjects additionally executed one fatiguing PIMA trial by pulling on an immovable resistance with 60% of the MVIC with each side and same position. Both regulative types mentioned were found during HIMA (I: n = 7, II: n = 17) and PIMA (I: n = 3, II: n = 9). During the fatiguing measurements, rHb decreased initially and started to increase in type II at an average SvO2-level of 58.75 ± 2.14%. In type I, SvO2 never reached that specific value during loading. This might indicate the existence of a threshold around 59% which seems to trigger the increase in rHb and could explain the two behavioral types. An approach is discussed to meet the apparent incompatibility of an increased capillary blood filling (rHb) despite high intramuscular pressures which were found by other research groups during isometric muscle actions.

Cryotherapy and compression in sports injury management: a scoping review

Background/Aims

For the management of sports injury, cryotherapy is commonly applied, yet modalities differ extensively in application including levels of compression. The aim of this study was to provide a comprehensive review of the current position in the literature on contemporary cryo-compression applications for musculoskeletal sports injury management.

Methods

A total of eight databases were searched: Sport Discus, Science Direct, CINHAL, Scopus, PubMed, Cochrane, ProQuest and MEDLINE. Publications were restricted to 30 years and had to be in the English language. Medical subject headings, free-text words, and limiting descriptors for concepts related to cryotherapy and compression for sports injury were applied. Inclusion criteria determined at least one modality of cryotherapy treatment applied simultaneous to compression or as a comparison, relevant to sports injury management. Modalities included cryo-compressive devices and gel/ice packs, in association with concomitant compression. Male, female, healthy and injured participants were included. Two reviewers independently selected eligible articles, resulting in 22 studies meeting the inclusion criteria following full-text appraisal.

Results

Inconsistent methodologies, low sample sizes and variability in outcome measures provided uncertainty over optimum protocols. A lack of previous understanding in the protocols in the available literature for isolated cryotherapy/compression applications prevents understanding of the therapeutic benefits of combined cryo-compression. No definitive agreement behind optimal cryo-compression applications were identified collectively from studies other than the consensus that compression aids the magnitude of cooling.

Conclusions

Although compression appears a useful adjunct to cooling modalities for the management of sports injury, no definitive agreement on optimum compression concurrent with cooling protocols were drawn from the studies. This was because of several methodological gaps in reporting throughout studies, highlighting a lack of studies that represent applications of compression and cryotherapy within a sporting context or applied nature within the available research.

Behavior of oxygen saturation and blood filling in the venous capillary system of the biceps brachii muscle during a fatiguing isometric action

The objective of the study was to develop a better understanding of the capillary circulation in contracting muscles. Ten subjects were measured during a submaximal fatiguing isometric muscle action by use of the O2C spectrophotometer. In all measurements the capillary-venous oxygen saturation of hemoglobin (SvO2) decreased immediately after the start of loading and leveled off into a steady state. However, two different patterns (type I and type II) emerged. They differed in the extent of deoxygenation (-10.37 ±2.59 percent points (pp) vs. -33.86 ±17.35 pp, p = .008) and the behavior of the relative hemoglobin amount (rHb). Type I revealed a positive rank correlation of SvO2 and rHb (ρ = 0.735, p <.001), whereas a negative rank correlation (ρ = -0.522, p <.001) occurred in type II, since rHb decreased until a reversal point, then increased averagely 13% above the baseline value and leveled off into a steady state. The results reveal that a homeostasis of oxygen delivery and consumption during isometric muscle actions is possible. A rough distinction in two types of regulation is suggested.

Arteriovenous Graft for Hemodialysis: Effect of Cryotherapy on Postoperative Pain and Edema

BACKGROUND

Arteriovenous grafting offers an alternative for patients whose vessels are unsuitable for arteriovenous fistula. However, as a result of subcutaneous tunnel dissection, postoperative pain and edema of the operated limb present early after surgery. As a traditional therapeutic approach, cryotherapy has the ability to suppress postoperative pain and edema.

AIMS

The purpose of the study was to investigate the feasibility of cryotherapy after arteriovenous graft surgery to decrease perioperative medication usage.

DESIGN

This study was a randomized controlled trial.

SETTING

A large integrated health care facility in South China.

PARTICIPANTS/SUBJECTS

A total of 85 hemodialysis patients who received arteriovenous graft surgery from March 2011 to February 2017 were enrolled.

METHODS

The participants were divided into an intervention group and a control group according to the postoperative management. Ice packs were applied covering the operative forearm for 120 minutes after wound closure in the intervention group. General information, pain score, analgesic consumption, wound inflammation, forearm edema, and participant satisfaction were compared between the two groups.

RESULTS

Cryotherapy-treated patients required less analgesia (26.19% vs. 48.84%, p < .05), reported lower pain score from 30 minutes to 48 hours postoperative (p < .05), less wound inflammation (11.90% vs. 25.58%, p < .05), and higher participant satisfaction (8.92 ± 0.57 vs. 6.52 ± 0.63, p < .05), whereas the incidence of forearm edema was equivalent (p > .05). No adverse events were reported in either group.

CONCLUSIONS

Cryotherapy is a preferable intervention for patients after arteriovenous graft implantation as a result of its favorable cost, convenience, and fewer side effects.

Cryotherapy Relieves Pain and Edema After Inguinal Hernioplasty in Males With End-Stage Renal Disease: A Prospective Randomized Study

CONTEXT

Tension-free hernioplasty under local anesthetic infiltration is a reasonable choice for end-stage renal disease patients with hernia.

OBJECTIVES

The purpose of the study was to investigate the feasibility of cryotherapy after hernioplasty surgery to relieve pain and scrotal edema.

METHODS

This was a prospective, randomized, and controlled trial held in a large integrated health care facility in South China. One hundred sixty-nine male patients on hemodialysis and scheduled for hernioplasty were enrolled between March 2013 and February 2017. The participants were divided into an intervention group and a control group. In the intervention group, ice packs were applied after surgery. Demographic information, vital signs, pain score, opioid consumption, wound inflammation, scrotal edema, and patient satisfaction were compared between the two groups. The primary outcome was pain score.

RESULTS

Cryotherapy-treated patients required less opioid consumption (5.95 vs. 15.29 mg; P < 0.05), reported lower pain scores from 30 minutes to 48 hours after operation (P < 0.05), less wound inflammation (11.90 vs. 32.94%; P < 0.05), lower incidence of scrotal edema in the first and second days (P < 0.05), and higher patient satisfaction (8.95 vs. 6.50 cm; P < 0.05), with stable vital signs throughout the monitoring period (P > 0.05).

CONCLUSION

Owing to its favorable cost, convenience, and low frequency of adverse effects, cryotherapy is useful for end-stage renal disease populations after hernioplasty to relieve pain and scrotal edema.

Cryotherapy-Induced Persistent Vasoconstriction After Cutaneous Cooling: Hysteresis Between Skin Temperature and Blood Perfusion

The goal of this study was to investigate the persistence of cold-induced vasoconstriction following cessation of active skin-surface cooling. This study demonstrates a hysteresis effect that develops between skin temperature and blood perfusion during the cooling and subsequent rewarming period. An Arctic Ice cryotherapy unit (CTU) was applied to the knee region of six healthy subjects for 60 min of active cooling followed by 120 min of passive rewarming. Multiple laser Doppler flowmetry perfusion probes were used to measure skin blood flow (expressed as cutaneous vascular conductance (CVC)). Skin surface cooling produced a significant reduction in CVC (P < 0.001) that persisted throughout the duration of the rewarming period. In addition, there was a hysteresis effect between CVC and skin temperature during the cooling and subsequent rewarming cycle (P < 0.01). Mixed model regression (MMR) showed a significant difference in the slopes of the CVC-skin temperature curves during cooling and rewarming (P < 0.001). Piecewise regression was used to investigate the temperature thresholds for acceleration of CVC during the cooling and rewarming periods. The two thresholds were shown to be significantly different (P = 0.003). The results show that localized cooling causes significant vasoconstriction that continues beyond the active cooling period despite skin temperatures returning toward baseline values. The significant and persistent reduction in skin perfusion may contribute to nonfreezing cold injury (NFCI) associated with cryotherapy.

Effects of cryotherapy methods on circulatory, metabolic, inflammatory and neural properties: a systematic review

Abstract Introduction: The cooling therapy (cryotherapy) is commonly used in clinical environmental for the injuries treatment according to its beneficial effects on pain, local inflammation and the recovery time of patients. However, there is no consensus in the literature about the effects of cryotherapy in the physiological reactions of affected tissues after an injury. Objective: To realize a systematic review to analyze the cryotherapy effects on circulatory, metabolic, inflammatory and neural parameters. Materials and methods: A search was performed in PubMed, SciELO, PEDro and Scopus databases following the eligibility criteria. Included studies were methodologically assessed by PEDro scale. Results: 13 original studies were selected and presented high methodological quality. Discussion: The cryotherapy promotes a significant decrease in blood flow, in venous capillary pressure, oxygen saturation and hemoglobin (only for superficial tissues) and nerve conduction velocity. However, the effect of cryotherapy on the concentration of inflammatory substances induced by exercise, as the creatine kinase enzyme and myoglobin, remains unclear. Conclusion: The physiological reactions to the cryotherapy application are favorable to the use of this therapeutic tool in inflammatory treatment and pain decrease, and demonstrate its importance in the neuromuscular system injuries rehabilitation.

Cold-induced vasoconstriction may persist long after cooling ends: an evaluation of multiple cryotherapy units

PURPOSE

Localized cooling is widely used in treating soft tissue injuries by modulating swelling, pain, and inflammation. One of the primary outcomes of localized cooling is vasoconstriction within the underlying skin. It is thought that in some instances, cryotherapy may be causative of tissue necrosis and neuropathy via cold-induced ischaemia leading to nonfreezing cold injury (NFCI). The purpose of this study is to quantify the magnitude and persistence of vasoconstriction associated with cryotherapy.

METHODS

Data are presented from testing with four different FDA approved cryotherapy devices. Blood perfusion and skin temperature were measured at multiple anatomical sites during baseline, active cooling, and passive rewarming periods.

RESULTS

Local cutaneous blood perfusion was depressed in response to cooling the skin surface with all devices, including the DonJoy (DJO, p = 2.6 × 10(-8)), Polar Care 300 (PC300, p = 1.1 × 10(-3)), Polar Care 500 Lite (PC500L, p = 0.010), and DeRoyal T505 (DR505, p = 0.016). During the rewarming period, parasitic heat gain from the underlying tissues and the environment resulted in increased temperatures of the skin and pad for all devices, but blood perfusion did not change significantly, DJO (n.s.), PC300 (n.s.), PC500L (n.s.), and DR505 (n.s.).

CONCLUSIONS

The results demonstrate that cryotherapy can create a deep state of vasoconstriction in the local area of treatment. In the absence of independent stimulation, the condition of reduced blood flow persists long after cooling is stopped and local temperatures have rewarmed towards the normal range, indicating that the maintenance of vasoconstriction is not directly dependent on the continuing existence of a cold state. The depressed blood flow may dispose tissue to NFCI.

The influence of dry needling of the trapezius muscle on muscle blood flow and oxygenation

OBJECTIVE

The purpose of this study was to investigate the effect of dry needling on the blood flow and oxygen saturation of the trapezius muscle.

METHODS

Twenty healthy participants participated in this study. One single dry needling procedure was performed in the right upper trapezius, at a point located midway between the acromion edge and the seventh cervical vertebrae. Using the oxygen to see device, blood flow and oxygen saturation were evaluated at the treated point and 3 distant points (similar point in the left upper trapezius and 30 mm laterally from this midpoint). Measurements were taken at baseline and in the recovery period (0, 5, and 15 minutes posttreatment).

RESULTS

After removal of the needle, the blood flow and oxygen saturation increased significantly from the pretreatment level in the treated point (P ≤ .001), and these values remained high throughout the 15-minute recovery period. There were only minor changes in the distant points.

CONCLUSIONS

These results suggest that dry needling enhances the blood flow in the stimulated region of the trapezius muscle but not in a distant region used in this study.

Compartmental and muscular response to closed soft tissue injury in rats investigated by oxygen-to-see and intravital fluorescence microscopy

BACKGROUND

Closed soft tissue injury (CSTI) induces local inflammation and progressive microvascular dysfunction. The aim of the study was to evaluate and compare the microvascular changes systematically in a precompartmental tissue injury by oxygen-to-see (O2C), a combined laser Doppler flowmetry and spectrophotometry system, and intravital fluorescence microscopy (IVM).

METHODS

Fourteen Wistar rats were subjected to a trauma and a control group (both n = 7). CSTI was performed on the left lower limb by means of a standardized impact device. Controls received a sham CSTI. Capillary blood flow (QRBC), oxygen saturation (sO2), and postcapillary filling pressure (rHb) were measured noninvasively by O2C assessed in 2-mm and 8-mm depth underneath the skin. Measurements were done before and after trauma and hourly up to 24 hours. IVM of the soleus muscle was performed after 24 hours.

RESULTS

Before CSTI, O2C parameters did not reveal a difference between both groups. Up to 2 hours after trauma, QRBC was significantly increased in 8-mm tissue depth. No significant changes of sO2 and rHb were noted compared with controls. In 2-mm depth, significantly reduced QRBC and rHb levels were observed compared with 8 mm but with no significant changes after CSTI. IVM showed a significant increase of postcapillary blood flow with decreased functional capillary density, increased macromolecular leakage, and increased nicotinamide adenine dinucleotide hydride.

CONCLUSIONS

After CSTI in rats, there was an immediate increase of compartmental capillary blood flow with a slight increase of muscle oxygen saturation and unchanged postcapillary venous filling pressures as sign of a redistribution of blood between soft and muscle tissue. The severity of pathologic changes in the compartment was not reflected by O2C but by IVM.

Standardized combined cryotherapy and compression using Cryo/Cuff after wrist arthroscopy

PURPOSE

cryotherapy and compression as integral part of the RICE regimen are thought to improve treatment outcome after sport injuries. Using standardized cryotherapy and compression perioperatively has been reported with conflicting clinical results. The impact of combined cryotherapy and compression is compared to standard care among patients undergoing wrist arthroscopy.

METHODS

fifty-six patients undergoing wrist arthroscopy were assessed, 54 patients were randomized to either Cryo/Cuff (3 × 10 min twice daily) or standard care over 3 weeks. Follow-up clinical visits were at postoperative days 1, 8, and 21. One patient in each group was lost during follow-up. Fifty-two patients were analyzed. Statistics were performed as Intention-to-treat analysis. Outcome parameters were pain, three-dimensional volume of the wrist, range of motion, and DASH score.

RESULTS

the Cryo/Cuffgroup had a 49% reduction in pain level (VAS 3.5 ± 0.4 vs. VAS 1.8 ± 0.2 on the 21st postoperative day) when compared to a reduction of 41% in the control group (VAS 5.1 ± 0.6 preoperatively vs. VAS 3.0 ± 0.5 on the 21st postoperative day). Swelling and range of motion were not as significantly different between the two groups as were DASH scores (DASH-score Cryo/Cuff group preoperatively 37.3 ± 3.5 and postoperatively 36.9 ± 3.5; DASH-score control group preoperatively 42.8 ± 4.3 and postoperatively 41.9 ± 4.9). The CONSORT score reached 17 out of 22.

CONCLUSION

there was no significant effect of additional home-based combined cryotherapy and compression using the Cryo/Cuff wrist bandage, following wrist arthroscopy regarding pain, swelling, range of motion, and subjective impairment assessed using the DASH score over 3 weeks in comparison with the control group.

Gender and eccentric training in Achilles mid-portion tendinopathy

The role of gender in Achilles tendinopathy is yet to be determined. We hypothesized that female patients respond the same as males to 12 weeks of painful eccentric training. A total number of 75 consecutive mid-portion patients with Achilles tendinopathy (25 females, 38 males) were enrolled in a cohort study with 63 being analyzed after 12 weeks according to their gender for tendon and paratendon microcirculatory mapping. Outcome was determined by pain on visual analogue scale, VISA-A score, Foot Ankle Outcome Score (FAOS), tendon and paratendon capillary blood flow, oxygen saturation, and postcapillary venous filling pressures. Eccentric training resulted in a morning resting pain reduction by 44% in males (P = 0.001) and by 27% in females (P = 0.08). VISA-A score improved in males by 27% from 63 +/- 12 to 86 +/- 13 (P = 0.036) and by 20% in females from 60 +/- 14 to 75 +/- 11 (P = 0.043, P < 0.05 for gender difference). Among females, only one out of five FAOS items was increased (sport 72 +/- 21 to 82 +/- 15, P = 0.045), while in males, four out of five items were increased (symptoms, pain, all-day-life, and sport, all P < 0.01). The microcirculatory gender-specific response to eccentric training revealed a greater postcapillary venous filling pressure reduction among symptomatic females and inconclusive capillary blood flow changes. No change in tendon oxygenation was noted in both genders. Symptomatic females suffering Achilles tendinopathy do not benefit as much as symptomatic males from 12 weeks of eccentric training. The pain reduction is significantly lower among symptomatic females in contrast to males, and the improvement in the FAOS and VISA-A scores is significantly lower among females in contrast to males. Additional treatment options warrant scrutiny to symptomatic females suffering Achilles tendinopathy beyond eccentric training.

Achilles tendon suture deteriorates tendon capillary blood flow with sustained tissue oxygen saturation - an animal study

BACKGROUND

Treatment of ruptured Achilles tendons currently constitutes of conservative early functional treatment or surgical treatment either by open or minimal invasive techniques. We hypothesize that an experimental Achilles tendon suture in an animal model significantly deteriorates Achilles tendon microcirculation immediately following suturing.

METHODS

Fifteen Achilles tendons of eight male Wistar rats (275-325 g) were included. After preparation of the Achilles tendon with a medial paratendinous approach, Achilles tendon microcirculation was assessed using combined Laser-Doppler and spectrophotometry (Oxygen-to-see) regarding:- tendinous capillary blood flow [arbitrary units AU]- tendinous tissue oxygen saturation [%]- tendinous venous filling pressure [rAU]The main body of the Achilles tendon was measured in the center of the suture with 50 Hz. 10 minutes after Achilles tendon suture (6-0 Prolene), a second assessment of microcirculatory parameters was performed.

RESULTS

Achilles tendon capillary blood flow decreased by 57% following the suture (70 +/- 30 AU vs. 31 +/- 16 AU; p < 0.001). Tendinous tissue oxygen saturation remained at the same level before and after suture (78 +/- 17% vs. 77 +/- 22%; p = 0.904). Tendinous venous filling pressure increased by 33% (54 +/- 16 AU vs. 72 +/- 20 AU; p = 0.019) after suture.

CONCLUSION

Achilles tendon suture in anaesthetised rats causes an acute loss of capillary perfusion and increases postcapillary venous filling pressures indicating venous stasis. The primary hypothesis of this study was confirmed. In contrast, tendinous tissue oxygen saturation remains unchanged excluding acute intratendinous hypoxia within the first 10 minutes after suture. Further changes of oxygen saturation remain unclear. Furthermore, it remains to be determined to what extent reduced capillary blood flow as well as increased postcapillary stasis might influence tendon healing from a microcirculatory point of view in this animal setting.

Frostbite of the feet after cryotherapy: a report of two cases

The use of cryotherapy for the reduction of postoperative swelling and pain has become commonplace in orthopedic, podiatric, and cosmetic surgery. Prolonged exposure to extreme cold may induce an injury nearly identical to that of frostbite. The authors report on 2 patients who underwent podiatric orthopedic surgery and were exposed to prolonged cold therapy, which resulted in limb-threatening problems. Both patients had prolonged and essentially uninterrupted application of cryotherapy for 4 to 7 days, resulting in rewarming injuries of tissue necrosis. A team of specialists used limb salvage therapy to successfully treat the patients. Because of the problems encountered with the cold therapy devices, the authors caution against unmonitored and prolonged cold exposure. Newer devices that prevent cold exposure below 65 degrees F for longer than 2 hours could be a better option in cases in which cryotherapy is used.

LEVEL OF EVIDENCE

4.

Midportion achilles tendon microcirculation after intermittent combined cryotherapy and compression compared with cryotherapy alone: a randomized trial

BACKGROUND

The effect of combined cryotherapy/compression versus cryotherapy alone on the Achilles tendon is undetermined.

HYPOTHESIS

Standardized combined cryotherapy/compression changes in midportion Achilles tendon microcirculation are superior to those with cryotherapy during intermittent application.

STUDY DESIGN

Controlled laboratory study.

METHODS

Sixty volunteers were randomized for either combined cryotherapy/compression (Cryo/Cuff, DJO Inc, Vista, California: n = 30; 32 +/- 11 years) or cryotherapy alone (KoldBlue, TLP Industries, Kent, United Kingdom: n = 30; 33 +/- 12 years) with intermittent 3 x 10-minute application. Midportion Achilles tendon microcirculation was determined (O2C, LEA Medizintechnik, Giessen, Germany).

RESULTS

Both Cryo/Cuff and KoldBlue significantly reduced superficial and deep capillary tendon blood flow within the first minute of application (43 +/- 46 arbitrary units [AU] vs 10 +/- 19 AU and 42 +/- 46 AU vs 12 +/- 10 AU; P = .0001) without a significant difference throughout all 3 applications. However, during recovery, superficial and deep capillary blood flow was reestablished significantly faster using Cryo/Cuff (P = .023). Tendon oxygen saturation was reduced in both groups significantly (3 minutes Cryo/Cuff: 36% +/- 20% vs 16% +/- 15%; KoldBlue: 42% +/- 19% vs 28% +/- 20%; P < .05) with significantly stronger effects using Cryo/Cuff (P = .014). Cryo/Cuff led to significantly higher tendon oxygenation (Cryo/Cuff: 62% +/- 28% vs baseline 36% +/- 20%; P = .0001) in superficial and deep tissue (Cryo/Cuff: 73% +/- 14% vs baseline 65% +/- 17%; P = .0001) compared with KoldBlue during all recoveries. Postcapillary venous filling pressures were significantly reduced in both groups during application; however, Cryo/Cuff led to significantly, but marginally, lower pressures (Cryo/Cuff: 41 +/- 7 AU vs baseline 51 +/- 13 AU; P = .0001 and KoldBlue: 46 +/- 7 AU vs baseline 56 +/- 11 AU; P = .026 for Cryo/Cuff vs KoldBlue).

CONCLUSION

Increased tendon oxygenation is achieved as tendon preconditioning by combined cryotherapy and compression with significantly increased tendon oxygen saturation during recovery in contrast to cryotherapy alone. Both regimens lead to a significant amelioration of tendinous venous outflow.

CLINICAL RELEVANCE

Combined cryotherapy and compression is superior to cryotherapy alone regarding the Achilles tendon microcirculation. Further studies in tendinopathy and tendon rehabilitation are warranted to elucidate its value regarding functional issues.

Local inflammatory and metabolic response in the knee synovium after arthroscopy or arthroscopic anterior cruciate ligament reconstruction

PURPOSE

The aim of this study was to study local synovial metabolism and inflammation after arthroscopy and arthroscopic anterior cruciate ligament (ACL) reconstruction.

METHODS

Microdialysis in the synovial membrane was performed during 4 hours postoperatively in 20 patients undergoing a minor arthroscopy procedure (e.g., meniscus surgery and 10 patients undergoing ACL reconstruction with a quadruple hamstring graft). Contralateral thigh adipose tissue served as a reference. Lactate, glucose, glycerol, and prostaglandin E(2) (PGE(2)) were monitored. The ACL group received intra-articular morphine preoperatively, and a cooling and compression device was applied postoperatively according to local clinical routines.

RESULTS

The synovial lactate levels and the consumption of synovial glucose was increased postoperatively in the arthroscopy group compared to the reference adipose tissue. There were no significant differences regarding synovial levels of glycerol, lactate, or glucose compared to the reference tissue in the ACL group. PGE(2) levels were significantly lower in the ACL group compared to the arthroscopy group.

CONCLUSIONS

A major arthroscopic surgical procedure (ACL reconstruction) did not increase the local synovial metabolism or induce a detectable inflammatory response compared to a minor arthroscopic surgical procedure (e.g., meniscal surgery) in our clinical setting. Intra-articular injection of morphine and or the use of a combined cooling and compression device in the ACL group showed a modulation of the response in tissue chemistry as measured by synovial microdialysis.

LEVEL OF EVIDENCE

Level III, therapeutic case-control study.

The role of tendon microcirculation in Achilles and patellar tendinopathy

Tendinopathy is of distinct interest as it describes a painful tendon disease with local tenderness, swelling and pain associated with sonographic features such as hypoechogenic texture and diameter enlargement. Recent research elucidated microcirculatory changes in tendinopathy using laser Doppler flowmetry and spectrophotometry such as at the Achilles tendon, the patellar tendon as well as at the elbow and the wrist level. Tendon capillary blood flow is increased at the point of pain. Tendon oxygen saturation as well as tendon postcapillary venous filling pressures, determined non-invasively using combined Laser Doppler flowmetry and spectrophotometry, can quantify, in real-time, how tendon microcirculation changes over with pathology or in response to a given therapy. Tendon oxygen saturation can be increased by repetitive, intermittent short-term ice applications in Achilles tendons; this corresponds to 'ischemic preconditioning', a method used to train tissue to sustain ischemic damage. On the other hand, decreasing tendon oxygenation may reflect local acidosis and deteriorating tendon metabolism. Painful eccentric training, a common therapy for Achilles, patellar, supraspinatus and wrist tendinopathy decreases abnormal capillary tendon flow without compromising local tendon oxygenation. Combining an Achilles pneumatic wrap with eccentric training changes tendon microcirculation in a different way than does eccentric training alone; both approaches reduce pain in Achilles tendinopathy. The microcirculatory effects of measures such as extracorporeal shock wave therapy as well as topical nitroglycerine application are to be studied in tendinopathy as well as the critical question of dosage and maintenance. Interestingly it seems that injection therapy using color Doppler for targeting the area of neovascularisation yields to good clinical results with polidocanol sclerosing therapy, but also with a combination of epinephrine and lidocaine.

Eccentric training decreases paratendon capillary blood flow and preserves paratendon oxygen saturation in chronic achilles tendinopathy

STUDY DESIGN

A controlled, randomized, prospective study,

OBJECTIVE

To assess the changes in paratendon microcirculation after 12 weeks of daily painful eccentric training in individuals with chronic Achilles tendinopathy.

BACKGROUND

Changes in tendon and paratendon microcirculation are evident in insertional and midportion Achilles tendinopathy. Whether the paratendon is involved in eccentric training response is not known.

METHODS

Twenty patients with chronic Achilles tendinopathy were recruited for a prospective, controlled trial using eccentric exercise. A laser Doppler system assessed capillary blood flow (flow), tissue oxygen saturation (SO2), and postcapillary venous filling pressure (rHb) at 8 paratendon locations at depths of 2 and 8 mm.

RESULTS

Pain in the eccentric-training group was reduced by 48% (from a mean of 4.1 +/- 2.9 to 2.1 +/- 2.2, P<.05). Deep paratendon blood flow decreased at the midportion paratendon location (P<.05). Superficial blood flow at the medial distal midportion position (by 31%, P = .008) and the lateral proximal midportion location (by 45%, P = .016) were significantly decreased postintervention, No significant change of superficial or deep paratendon oxygenation was found after intervention as compared to baseline. Deep paratendon postcapillary venous filling pressures were significantly reduced following eccentric training (P<.05).

CONCLUSION

An eccentric-training program performed daily over 12 weeks reduced the increased paratendinous capillary blood flow in Achilles tendinopathy by as much as 45% and decreased pain level based on a visual analog scale. Local paratendon oxygenation was preserved while paratendinous postcapillary venous filling pressures were reduced after 12 weeks of eccentric training, which appears to be beneficial from the perspective of microcirculation.

Palmar microcirculation does not deteriorate 2 years after radial artery harvesting—implications for reconstructive free forearm flap transfer

BACKGROUND

The functional consequences after radial artery-based forearm flaps for hand microcirculation remain unclear. We hypothesized that palmar microcirculation is compromised after radial artery removal in arteriosclerotic patients.

MATERIALS AND METHODS

A total number of 114 patients were included undergoing elective coronary revascularization using the radial artery of the nondominant forearm with non-pathological Allen's test. Palmar microcirculatory mapping with 1596 measurements was applied 2 years after removal of the radial artery regarding capillary flow, finger tip oxygenation, as well as postcapillary venous filling pressures throughout both hands using combined noninvasive real-time laser Doppler flowmetry and spectrophotometry.

RESULTS

Only 2/56 positions revealed a difference beyond a 5% threshold 25 +/- 5 months after radial artery removal. Superficial capillary blood flow decreased by 13% at the hypothenar eminence (242.0 +/- 153.6 vs 275.6 +/- 169.2, p = 0.009). Deep postcapillary venous filling pressure (8 mm) was significantly increased by 9% only at the fingertip of the fifth finger (112.4 +/- 49.7 vs 103.0 +/- 25.0, p = 0.033). No clinical signs of malperfusion were found after radial artery removal, and no patient was impaired in his daily palmar motor activity.

CONCLUSIONS

Pedicled removal of the radial artery does not compromise superficial or deep palmar capillary blood flow, finger tip oxygenation, or postcapillary venous filling pressures in a long-term perspective in arteriosclerotic patients. No clinical relevant signs of malperfusion or any deterioration of palmar motor function was encountered. The blood flow via the ulnar artery and the interosseal artery compensates palmar perfusion without microcirculatory deterioration even more than 2 years after removal of the radial artery.

Changes of Achilles midportion tendon microcirculation after repetitive simultaneous cryotherapy and compression using a Cryo/Cuff

BACKGROUND

Cryotherapy and compression have been shown to decrease pain and improve function. The dosage and timing of these options remain unclear.

PURPOSE

To examine the effects of a standardized compression and cryotherapy device (Cryo/Cuff) on midportion Achilles tendon microcirculation during intermittent administration.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Twenty-six subjects were included (13 men and 13 women; age, 32.3 +/- 12 years; body mass index, 25.4 +/- 5 kg/m(2)). Each underwent three 10-minute applications of the device, followed by a 10-minute recovery period. A continuous real-time assessment of parameters of Achilles tendon midportion microcirculation was performed with a laser Doppler spectrophotometry system.

RESULTS

Superficial tendon oxygen saturation dropped significantly from 35.9 +/- 21 arbitrary units (AU) to 13.5 +/- 15, 15.9 +/- 16, and 11.1 +/- 11 AU (P = .0001) during each period of cryo-compression, respectively. There was significant increase during the recovery period (55.4 +/- 29, 65.2 +/- 26, and 65.7 +/- 27 AU; P = .003), up to +83% of the baseline level. At 8-mm tendon depth, cryo-compression preserved local oxygen with -4% (P = .001) of the baseline level and small but significant increased oxygen saturation of up to +13% (P = .0001). Relative postcapillary venous tendon filling pressures were favorably reduced both superficially (57% +/- 34%, 67% +/- 27%, and 64% +/- 38%, respectively; P = .0004) and deep (76% +/- 13%, 79% +/- 11%, and 78% +/- 18%, respectively; P = .0002). Superficial capillary blood flow was reduced from 48.4 +/- 48 to 5 +/- 7, 4 +/- 5, and 3 +/- 4 AU at each period, respectively (-94%, P = .0003), with increased flow during recovery periods of up to 58 +/- 64, 58 +/- 79, and 47 +/- 71 AU, respectively (+20%, P = .265). Deep flow was reduced from 197 +/- 147 to 66.7 +/- 64, 55 +/- 46, and 43 +/- 39 AU, respectively (-78%, P = .0002) without increase during recovery periods.

CONCLUSION

Cryo/Cuff exerts beneficial effects on the microcirculatory level of the midportion Achilles tendon with decreased capillary blood flow, preserved deep tendon oxygen saturation, and facilitated venous capillary outflow.

Intermittent KoldBlue cryotherapy of 3x10 min changes mid-portion Achilles tendon microcirculation

BACKGROUND

Neovascularisation and microcirculatory changes have been reported in Achilles tendinopathy. Cryotherapy and compression, as part of a rest, ice, compression and elevation regimen, are shown to decrease pain and improve function. However, the microcirculatory changes following a given dosage of cryotherapy on mid-portion Achilles tendon remain unclear.

STUDY DESIGN

Prospective clinical cohort study, level of evidence 2.

METHODS

30 people (12 males, 33 (SD 12) years, body mass index 25.6 (5.3) kg/m2) were included in the cohort. 3x10 min KoldBlue ankle-cooling bandages were applied and microcirculation of Achilles tendon mid-portion was real-time and continuously assessed using a laser-Doppler-spectrophotometry system (O2C, Germany).

RESULTS

Superficial capillary blood flow was reduced from 42 to 6, 5 and 3 relative units (rU) in the first, second and third cryotherapy periods, respectively (-65%, p = 0.001), with no significant capillary hyperaemia. Deep capillary tendon blood flow was reduced from 180 to 82, 53 and 52 rU (-71%, p = 0.001) within 6-9 min of application without hyperaemia. Superficial tendon oxygen saturation dropped significantly from 43% to 26%, 18% and 11% (p = 0.001) after repetitive cryotherapy, with persisting increase of tendon oxygenation during rewarming (51%, 49% and 54%, p = 0.077) up to 27% of the baseline level. At 8 mm tendon depth, cryotherapy preserved local oxygenation. Relative postcapillary venous tendon filling pressures were favourably reduced from 41 (11) to 31, 28 and 26 rU (-36%, p = 0.001) superficially and from 56 (11) to 45, 46 and 48 rU (-18%, p = 0.001) in deep capillary blood flow during cryotherapy, facilitating capillary venous clearance.

CONCLUSION

Intermittent cryotherapy of 3x10 min significantly decreases local Achilles tendon mid-portion capillary blood flow by 71%. Within 2 min of rewarming, tendon oxygen saturation is re-established following cryotherapy. Postcapillary venous filling pressures are reduced during cryotherapy, favouring capillary venous outflow of the healthy Achilles tendon.

Eccentric training in Achilles tendinopathy: is it harmful to tendon microcirculation?

BACKGROUND

Eccentric training has been shown to reduce pain and gain function in patients with chronic Achilles tendinopathy. However, currently no data are available regarding any potential adverse effects of an eccentric training intervention on Achilles tendon microcirculation.

METHODS

59 patients (49 (12) years; body mass index 27 (5); 49 mid-portion, 10 chronic insertional tendinopathy) with 64 symptomatic (54 mid-portion, 10 insertional) Achilles tendons were prospectively enrolled. Baseline tendon microcirculation at four distinct tendon positions from the insertion to the proximal mid-portion area was assessed using a laser Doppler system for capillary blood flow, tissue oxygen saturation and postcapillary venous filling pressure. A 12-week daily painful home-based eccentric training regimen was initiated (3x15 repetitions per tendon and day).

RESULTS

Achilles tendon capillary blood flow was significantly reduced at the insertion (by 35%, p = 0.008) and the distal mid-portion area (by 45%, p = 0.015) at 2 mm and by 22% (p = 0.007) and 13% (p = 0.122) at 8 mm tissue depths, respectively. Achilles tendon oxygen saturation was not decreased after the 12-week eccentric training regimen throughout the insertion to the proximal mid-portion area (insertion 72 (13) vs 73 (10), proximal mid-portion 63 (13) vs 62 (11), both NS). Achilles tendon postcapillary venous filling pressures were significantly reduced at the insertion (51 (16) vs 41 (19), p = 0.001) and the distal mid-portion (36 (13) vs 32 (12), p = 0.037) at 2 mm and at the insertion at 8 mm (63 (19) vs 51 (13), p = 0.0001). Pain was reduced from 5.4 (2.1) to 3.6 (2.4; p = 0.001) in the mid-portion and from 6 (2.5) to 3.2 (2.7; p = 0.002) in the insertional tendinopathy group. No Achilles tendon rupture or any interruption during the eccentric training was noted among the 59 patients.

CONCLUSION

Daily eccentric training for Achilles tendinopathy is a safe and easy measure, with beneficial effects on the microcirculatory tendon levels without any evident adverse effects in both mid-portion and insertional Achilles tendinopathy.

Long-term palmar microcirculation after radial artery harvesting: an observational study

BACKGROUND

The aim of this study was to assess palmar microcirculation in a long-term follow-up after radial artery harvesting for coronary revascularization.

METHODS

One hundred fourteen patients (100 male; aged 61.7 +/- 6.7 years; preoperative New York Heart Association 2.3 +/- 0.6, ejection fraction 61.4% +/- 13.9%) were included after undergoing elective coronary revascularization using the radial artery of the nondominant forearm with a nonpathologic Allen's test. Superficial and deep tissue oxygen saturation (SO2), postcapillary venous filling pressure (rHb), capillary blood flow, and capillary blood flow velocity were determined at a mean 25 +/- 5 months after surgery using a combined laser Doppler spectrophotometry system.

RESULTS

At 2-mm tissue depth, there was a small, but significant, decrease of 3% of superficial SO2 at the thumb and the thenar eminence (D1: 75.3% +/- 8.9% versus 77.6% +/- 9.7%, p = 0.003; thenar: 71.5% +/- 10.5% versus 73.2% +/- 8.2%, p = 0.027). Deep palmar SO2 was changed significantly at 5 of 7 positions by 3%. Deep postcapillary venous filling pressure (8 mm) was significantly increased by 9% only at the fingertip of the fifth finger (112.4 +/- 49.7 versus 103.0 +/- 25.0, p = 0.033), while superficial capillary blood flow decreased by 13% at only 1 of 7 positions at the hypothenar eminence (242.0 +/- 153.6 versus 275.6 +/- 169.2, p = 0.009). Overall, only 2 of 56 positions exceeded a given threshold of 5% change of microcirculation. No clinical signs of malperfusion were found (postoperative New York Heart Association 1.1 +/- 0.4, p < 0.05), and no patient was impaired in daily palmar motor activity.

CONCLUSIONS

Long-term objective evaluation of superficial and deep palmar microcirculation confirms that radial artery harvesting for coronary revascularization does not compromise palmar microcirculation.