Effects of Ultrasound Therapy on MCL Injuries

make of sonography Therapy on MCL InjuriesThe medial confirmatory ligament (MCL) is one of the virtually oftentimes injured ligaments of the knee joint. Fortunately, most patients who sustain MCL injuries ar able to earn their previous direct of activity without the drive for surgical preaching. withal, the most fearful injuries, especially those involving multiple ligaments, whitethorn require operative repair. This pick up al starting time explore the perfumeiveness of a conservative treatment, namely echography therapy and habit therapy, in the treatment of MCL injuries of the knee joint. In a recap by Phisitkul, James, Wolf, and Amendola (2006), treatment with early footslog of motion (ROM) exercises and progressive strengthening has been showingn to pee-pee actually good results. ultrasonography therapy has been a widely physical exertiond and well-accepted fleshly therapy modality for musculoskeletal conditions for many years. Wong, Schumann, Townsend, an d Phelps (2007) performed a survey near the use of sonography by physical therapists who ar orthopaedic specialists, and entrap that ultrasonography therapy is a popular adjunct in orthopaedic physical therapy and that it is sensed as primary(prenominal). so far, the lack of studies confirming its benefits has led many to question this conventionalistic view. Indeed, many analyze which explored the issuingiveness of sonography therapy failed in passing a explicit conclusion. Nevertheless, it arouse non be assumed that this lack of attest implies that ultrasonography therapy is in incumbranceive, and thus further research is needed to establish the adequacy of its use.This hire aims at respondent the following crucial questions In patients with MCL injuries of the knee, suffer ultrasonography improve throe, hindrance and general recovery? Is it to a great extent than put upive than exercise therapy in conk out symptoms? An answer to these questions pu ll up stakes help to better direct physiotherapy treatment for these patients, and thus optimize recovery.Subsequent chapters lead discuss the current lit uncommitted on the subject, followed by the methodology utilise in this study. The results argon then presented and analysed. The interpretation of results in the context of previous research will be discussed in the discussion chapter, including the strengths and limitation of the study.Literature ReviewUltrasound therapy has become comm still utilize in soft waver injuries (Speed, 2001). enquiry carried out in the past few decades regarding the personal do of ultrasonography on proboscis tissue papers will be discussed below. My aim is to study the research available from the past years in attempt to find conclusive and arranged results regarding the cause of ultrasound, and thus to justify the use of ultrasound in the clinical setting, unique(predicate)ally to treatment of medial collateral ligament injuries.As will be discussed in this chapter, when ultrasound enters the body, it is concept to exert an effect on it by thermal and non-thermal mechanisms (Robertson, Ward, Low, Reed, 2006, p.266). round of these make whitethorn stimulate improve so far others may be dangerous and may catch damage.Thermal effects of ultrasoundAs ultrasound waves travel trough body tissues, they cause oscillation of particles, thus converting sonic efficacy into wangle energy. The amount of heat produced will greatly depend upon the posture given and the appraise of energy absorption, but alike on certain tissue properties, such as the heat capacity, efficiency of heat transfer, and the tissue distribution and space (Robertson, Ward, Low, Reed, 2006, p.266). Some authors stir showed pre- heat up the ara of treatment to achieve a greater development in tissue temperature (Draper et al 1998a).Living tissue will be affected by an addition in temperature in miscellaneous variant ways. Accordi ng to Speed (2001), the thermal effects of ultrasound include an switch magnitude extensibility in tissues, enhanced stock certificate conflate, fuss modulation, decrementd joint cruelty and vigour spasm, together with a mid inflammatory response. These could explain why a temporary enlarge in range of motion is detect later on ultrasound treatment (Draper et al., 1998b Knight et al., 2001). Hayes, Merrick, Sandrey and Cordova (2004) studied the extent of heating in tissue at 2.5cm depth and tack together that 3 megacycle ultrasound was more effective in heating the tissues at this depth than 1MHz, reaching a temperature of 40 degrees Celsius after(prenominal) 4 legal proceeding. Unfortunately the production of heat may place the patient at risk of a contend combustion if utilise incorrectly (Robertson, Ward, Low, Reed, 2006, p.290).Physical effects of ultrasoundCavitationCavitation is the formation of niggling gas bubbles in the tissues as a result of ultrasound s hiver (Robertson, Ward, Low, Reed, 2006, p.267). Johns (2002) explains how as sound waves travel through the tissues, the characteristic compression and rarefaction causes microscopical gas bubbles present in the tissue fluid to contract and expand. disfigurement to the cadre may descend when these gas bubbles expand and collapse rapidly. Nevertheless, cavitation has been launch to get only when apply high intensities, and thus it is unlikely to occur in vivo with therapeutic levels (Nyborg, 2001). However according to a follow-up by Baker, Robertson, and Duck (2001), there are a few studies which suggest the ensnareing of in vivo cavitation. Baker and his colleagues argue that these studies were not replicated and that results obtained may guide been callable to difficulty with the analysis of B-scan resource, which were used to measure cavitation. A recent study enquired the method by which cavitation is detected. The wavelet approach was identified as a new tool for studying bubble cavitation (Zhou, 2008). Cavitation becomes clinically relevant during ultrasound applications in water, as bubbles that form amid the skin and the treatment guide on may block transmission of ultrasonic waves (Ward Robertson, 1996). acoustic streamingAcoustic streaming may be described as a flow of liquid caused by a generation of pressure along the axis of the beam of energy and on any other structures which reflect it (Robertson, Ward, Low, Reed, 2006, p.268). on that point are two characters of acoustic streaming microstreaming and pop streaming (Duck, as cited in Baker, Robertson Duck, 2001). Bulk streaming occurs in any fluid and develops as the ultrasound beam is propagated, while microstreaming occurs at a microscopic level and is formed as eddies of flow flanking to an oscillating surface (Robertson, Ward, Low, Reed, 2006, p.268).Unfortunately bulk streaming is oftentimes less windup(prenominal)ly powerful, with microstreaming being the only typ e of acoustic streaming which is able to stimulate booth activity and lurch tissue layer permeability (Duck, as cited by Baker, Robertson, Duck, 2001). Microstreaming can produce test on the cell membrane and wash away any molecules and ions which hoard outside the cell membrane (Robertson, Ward, Low, Reed, 2006, p.268). According to Duck (as cited by Baker, Robertson, Duck, 2001), only bulk streaming occurs in vivo, because microstreaming only occurs secondary to cavitation. In vitro studies show diverge magnitude growth cipher production by macrophages ( youngish and Dyson, 1990a), summationd atomic number 20 uptake (Mortimer and Dyson, 1988), increased secretion and degranulation of mast cell (Fyfe and Chahl, 1984) and increase cell membrane permeability (McCance and Huether, as cited by Baker, Robertson, Duck, 2001) by microstreaming. This even will turn in minimal relevance in the clinical setting if one assumes that cavitation will not occur. Nevertheless, Manas seh, Tho, Ooi, Petkovic-Duran, and Zhu, (2010), suggest that microstreaming which occurs secondary to cavitation will play a social occasion in the action of microbubbles in therapeutic ultrasound.Standing wavesStanding waves are formed when reflected sound waves are superimposed with incident waves, and are characterized by high pressure peaks, the antinodes and zones of low pressure known as nodes (Robertson, Ward, Low, Reed, 2006, p.267-8). Ter Haar and Wyard (1978) delegate forward that stock cell stasis may occur with ultrasound, with cells forming at half(prenominal) wavelength intervals in the blood vessels at antinodes. These results match those by Dyson, puddle, Woodward, and Broadbent (1974). The latter studied the effect of a stationary wave on blood cell stasis and endothelial damage in blood vessels of chick embryos. The cells form bands half a wavelength apart inside blood vessels. They suggest that under optimum conditions, the minimum vehemence of less than 0 .5 Wcm-2 at 3 MHz with nonstop irradiation is required for stasis to occur. Damage to some endothelial cells of vessels in which stasis has occurred was revealed by an electron microscope. hence, it is suggested that the treatment head is continuously moved during the treatment to defame the formation of standing waves (Robertson, Ward, Low, Reed, 2006, p.268).The effect of ultrasound on repair of body tissuesAccording the following research, ultrasound therapy may have an effect on cells involved in repair of body tissues, includingLevels of prostaglandins and leukotrienesLeung, Ng, and Yip (2004) performed a randomized, case-control study to study the effect of ultrasound during the acute inflammation of soft-tissue injuries. They mensurable the levels of leukotriene B4 and prostaglandin E2 in the medial collateral ligament of rats and name that pulsed ultrasound (14) use for five proceeding at different durations and intensities may stimulate acute inflammation by increasing the levels of the above mentioned leukotriene and prostaglandin.Release of fibroblast from macrophagesYoung and Dyson (1990a) studied if ultrasound therapy can increase the release of fibroblast mitogenic factors from macrophages in vitro, and assessed fibroblast proliferation over five days. This study showed an increased secretion of already formed fibroblasts in macrophages at 0.75 MHz ultrasound, which may be caused by permeability changes. On the other hand, at 3 MHz relative relative relative frequency, ultrasound appeared to encourage both(prenominal) the price reduction and secretion of fibroblast mitogenic factors. The contend why these two frequencies cause different effects may be explained by the different physical mechanisms involved. Williams (as cited in Young, 2002, p. 217), argues that cavitation is more liable to occur at lower frequencies, while at a higher(prenominal) frequency heating is more likely.Platelets and -thromboglobulinWilliams, Chater, Allen, S herwood, and Sanderson (1978) investigated the effect of ultrasound on platelets and established that more -thromboglobulin, a platelet specific protein, was released by ultrasound therapy. They suggest that this protein is released both by the disruption of platelets by cavitation and by other aggregating agents liberated in parallel with it which cause a release reaction in the bordering platelets. This however, has not been proved to happen in vivo.Histamine release from mast cellsFyfe and Chahl (1984) suggest that ultrasound applied in the therapeutic range causes a significant increase in degranulated mast cells and thus an increase in histamine release, in rats. They suggest the accident that ultrasound increases the permeability of mast cells to atomic number 20 causing them to degranulate, resulting in an increase in local blood flow. On the other hand, when Hogan, Burke, and Franklin (1982) investigated the change in blood flow in rat muscle on insonation, they found tha t arterioles vasoconstrict transiently in response to insonation, but improve perfusion after long-term treatment. attach membrane permeability to calciumChange in the permeability of membranes to calcium has been demonstrated when using therapeutic ultrasound. According to Al-Karmi, Dinno, Stoltz, Crum, and Matthews (1994), applying ultrasound for two minutes will cause a significant boost in loft conductance in the presence of calcium ions, thus confirming that calcium ions enamour the biological effects of ultrasound. Dinno et al. (1989) also used a frog skin model to study the effect of ultrasound on membranes. They argue that the increase in the concentration of calcium ions inside cells which occurs after the application of ultrasound, may decrease the permeability of gap junctions and uncouple cells in the way by which cells differentiate. Therefore, they reason that ultrasound can affect cell differentiation and because histogenesis, and thus its use should be avoided ove r embryonic tissue.Growth factor secretionIto, Azuma, Ohta, and Komoriva (2000) applied ultrasound to a co-culture system of human osteoblastic and endothelial cells and studied their effect on growth factor secretion. Their study showed that ultrasound increases the levels of platelet-derived growth factor. This may be the reason for improved good luck better rate with ultrasound treatment, as discussed later.Fibroblasts and Collagen synthesisRamirez, Schwane, McFarland, and Starcher (1997), conducted an investigation to determine the effect of ultrasound on the rate of cell proliferation and collagen synthesis by using cultured fibroblasts form the Achilles tendons of neonatal rats. They found an increase in collagen synthesis and rate of thymidine incorporation and DNA content after ultrasound treatment, suggesting that ultrasound stimulates the synthesis of collagen in tendon fibroblasts and cell division after injury. In a more recent study Chiu, Chen, Huang, and Wang (2009), studied the effect of ultrasound on the proliferation of human skin fibroblasts at different frequencies. They applied ultrasound for three minutes daily for three days and found an increase in fibroblast proliferation by both 1 and 3 MHz frequencies, with less stimulation when using 0.5 MHz frequency. Chiu et al., also took into account temperature changes and found a change of only one degree Celsius after insonation, thereby implying that the results observed where due to non-thermal effects.This can be explained by the increase in protein synthesis found to occur in fibroblasts after ultrasound treatment. Harvey, Dyson, Pond and Grahame (1975) suggest that therapeutic ultrasound at 3 MHz frequency and at an intensity of 0.5 2.0 Wcm-2, can directly stimulate protein synthesis in fibroblasts, without any other cells acting as mediators. In fact they attributed this to membrane-associated changes. Nevertheless, the increase in fibroblast proliferation may occur as a result of the effects of ultrasound on macrophages, which release fibroblasts mitogenic factors (Young Dyson, 1990a), as previously discussed.Ultrasound not only stimulates fibroblasts to produce more collagen (Ramirez et al. 1997), but the collagen produced also has a higher tensile strength and is better organized and aggregated. Okita et al. (2009) studied joint mobility and collagen filum arrangement in the endomysium of immobilized rat soleus muscle, and showed that therapeutic ultrasound may prevent changes in joint mobility and collagen fibril movement which occur with immobility. In contrast, when Larsen, Kristensen, Thorlacius-Ussing and Oxlund (2005) studied the influence of pulsed ultrasound at 3 MHz frequency and different intensities, on the mechanical properties of better tendons in rabbits, they found greater extensibility after insonation with higher intensities, however there was no significant change of the point of rupture when the tendons were loaded, suggesting that pulse d ultrasound did not improve the mechanical properties of the healing tendons.AngiogenesisTherapeutic ultrasound may also affect the rate of angiogenesis. Young and Dyson (1990b) considered the formation of new blood vessels in full-thickness lesions of flank skin in adult rats and found that by day 5 post-injury, ultrasound tough wounds had developed a greater number of blood vessels, and were thus at a more advanced stage in the repair process. However by the seventh day, there was no significant difference between the groups.Therapeutic mechanismOn the basis of these conflicting results, two initiates of thought were developed. The evidence-based or factual school considers heat as the only effect of ultrasound therapy and thus emphasise the use of high doses and give comminuted value to low intensity and pulsed treatment. This view is found in most American writing about this subject. On the other hand, the other school of thought is largely European, and is more involved in the biological and mechanical effects of pulsed low-intensity treatments (Robertson, Ward, Low, Reed, 2006, p. 269).Robertson, Ward, Low, Reed, (2006, p. 269) suggest that clinical studies may be used to investigate which doses produce better outcomes. In vitro studies can provide a dose-response birth which may provide information about the most effective dose. Nevertheless, effects demonstrated in vitro, such as cavitation and acoustic streaming have not yet been shown to occur in vivo, since it is difficult to produce doses in vivo which are comparable to dose in vitro. They argue that in vitro, ultrasound is applied to only a thin layer of cells, and thus the famous changes do not necessarily occur when applied to a much larger volume of tissue in vivo. Moreover, in vitro the energy is hold in to a very small volume and thus the power concentration will be much higher than in vivo.Therapeutic effects of UltrasoundUltrasound therapy has been claimed effective in a wide rang e of clinical conditions, however there are still difficulties in establishing the force of ultrasound with certainty and in identifying a dose-response relationship, if there is any. Some of the supposed effects of ultrasound include promotion of fracture healing, soft tissue healing, articular cartilage repair, pain suspension, increase local blood flow, change the extensibility of scar tissue and for the diagnosis of a stress fracture, and will be discussed below.Fracture healingUltrasound has been proposed to promote the processes involved in fracture healing and thus increase its rate. Sun et al., (2001) investigated the effects of low-intensity pulsed ultrasound on arise cells in vitro, and found a significant increase in osteoblast cell counts and a significant decrease in osteoclast cell count after stimulation, suggesting a positive effect on the jam-healing process. Nolte et al., (2001) also studied the in vitro effects of low intensity ultrasound. The latter used foe tal mouse metatarsal rudiments and found an increase in length of the calcified diaphysis, which was chief(prenominal)ly greater in the ultrasound tempered groups compared to the untreated groups, after 7 days. Therefore they cerebrate that low-intensity ultrasound directly affects osteoblasts and ossifying cartilage, with consequential more active ossification.Cyclooxygenase-2 regulates the production of Prostaglandin E2 by osteoblasts, both of which are thought to be an essential part of fracture healing (Zhang et al., 2002). Ultrasound stimulation has been found to increase cyclooxygenase-2 expression and to promote bone formation in osteoblast via various signalling pathways (Tang et al., 2006). Together with prostaglandins, nitrous oxide is a crucial mediator in early mechanically induced bone formation. Reher et al., (2002), investigated the effect of traditional (1MHz, pulsed 14) and a long-wave (45 kHz, continuous) ultrasound on nitric oxide induction and prostaglandin E2 production in vitro, on human mandibular osteoblasts. A control group was set which was treated with sanctimoniousness ultrasound. They found a significant increase in both induced nitrate and prostaglandin E2 production. foresightful wave ultrasound was found to be more effective than the traditional ultrasound.Other studies suggest that ultrasound may have an effect on the regulation of genes necessary for osteogenesis. Suzuki and his colleagues (2009) studied the typical osteoblastic cell line in the presence or absence of daily low intensity pulsed ultrasound stimulation at 1.5 MHz frequency, and 30 mW/cm2 intensity, for 20 minutes, for 2 weeks. They concluded that stimulation with these parameters directly affected osteogenic cells, leading to mineralized nodule formation, thus low intensity pulsed ultrasound therapy is likely to have an influence on the activities of osteoblasts in alveolar bone.Clinical studies gave controversial conclusions in this area. In a review, Bu sse et al., (2002) concluded that evidence form randomised controlled trials suggest that low intensity pulsed ultrasound therapy may significantly reduce the time of fracture healing for non-operatively treated fractures. Five years later, Walker, Denegar, and Preische, (2007) confirmed this finding through another review. Moreover, Della Rocca (2009) reviewed studies about the effects of low-intensity pulsed ultrasound treatment in fracture healing and found a large body of animal and cellular research which shows this to be beneficial in simulating faster normal fracture healing. However, from a review to of randomised controlled trials to determine the effectiveness of low intensity pulsed ultrasound in fracture healing, Busse et al., (2009), concluded that the evidence available has a moderate to very low quality and provides conflicting results.Pain reliefThere are a very small number of studies which investigate the effectiveness of ultrasound in pain relief. Nevertheless, as suming that ultrasound promotes healing and resolves inflammation, pain should hence decrease. Levent, Ebru, and Gulis (2009), used a randomised controlled trial to study the effect of ultrasound therapy in knee osteoarthritis. They applied ten school terms of five minutes of continuous ultrasound at 1 MHz to the experimental group and sham ultrasound to the control group to act as a placebo. They assessed pain by a visual analogue scale (VAS) and found that the decrease in pain in the experimental group is statistically significantly more than the control group. Thus they concluded that therapeutic ultrasound can be used effectively as a pain relief modality in patient suffering from knee osteoarthritis.An earlier review by Brosseau et al., (2001), did not show ultrasound as clinically important for pain relief in people with patellofemoral pain syndrome. However, they were unable to sequester a conclusion regarding its use due to methodological flaws and limitations in the stud ies include in this review.Soft tissue injuriesWilkin, Merrick, Kirby and Devor (2004) studied the effect of pulsed ultrasound applied once daily for a week, on the healing of skeletal muscle in eighty rats. The results suggest that pulsed ultrasound as administered did not urge or improve regeneration of skeletal muscle tissue after contusion. Similarly, Markert, Merrick, Kirby and Devor (2005), using a randomized controlled trial with rats, found no evidence that specific continuous ultrasound and exercises protocols enhance skeletal muscle tissue regeneration following contusion injury.Takakura et al. (2002) investigated the effect of low-intensity pulsed ultrasound on the rate of healing of injured medial collateral ligaments of rat knees and found a significant improvement in the mechanical properties on the twelfth day, which however was lost by the twenty-first day. Nevertheless they also observed a larger mean fibril diameter in the ligaments treated with ultrasound, last( a) that low intensity pulsed ultrasound enhances the early healing of medial collateral ligament injuries.Ebenbichler et al., (1999) investigated the effect of ultrasound in the treatment of calcific tendinitis. This study suggests better outcomes with ultrasound treatment. Since only patients with calcific tendinitis diagnosed by diagnostic imaging were included in the study, results are more valid than if numerous elevate pathologies with different cellular process were included. This study was included in the review by Alexander et al., (2010). The latter carried out a review from various electronic databases and identified eight randomised controlled trials out of a correspond of seven hundred and twenty seven, which met their inclusion criteria. All the studies reviewed focused on shoulder musculoskeletal disorders. They concluded that statistically significant improvements were observed broadly in studies which used higher levels of total energy and those who used chronic exposure times. They noted favourable outcomes when at least 2,250J per treatment session was applied. This is further suggested by the frequency resonance hypothesis, which suggests that the mechanical energy produced by the ultrasound wave may be absorbed by proteins, mend the structure of individual proteins or changing the function of a multi-molecular complex. Thus it may affect enzymatic proteins, inducing temporary conformational shifts, and thus alter the enzyme activity and cell function. This hypothesis implies that different frequencies will cause whimsical resonant or shearing forces which will therefore have specific effects at cellular and molecular levels (Johns, 2002). Thus further reviews should come up to different parameters used in different studies, in attempt to establish effective doses.Blood flowNoble, Lee, and Griffith-Noble (2007) applied ultrasound at 3 MHz frequency and 1 Wcm-2 for 6 minutes to assess its effect upon cutaneous blood flow by laser Doppl er flowmetry. They also measured skin temperature. They concluded that cutaneous blood flow increased significantly with ultrasound even though no significant changes in temperature had occurred. Nevertheless, blood flow changes in skeletal muscles have not yet been established. Robinson and Buono (1995), investigated the effect of continuous ultrasound on blood flow using 1.5 Wcm2 intensity for 5 minutes and found no significant change in skeletal muscle blood flow.Wound healingOther authors have studied the healing rates varicose ulcers by ultrasound and found more marked healing of insonated ulcers (Dyson, Franks, Suckling, 1976). However more recent studies suggest that ultrasound does not have an influence on the acceleration of healing or final stage of the wound healing (Dolibog, Franeki, Taradai, Blaszczak, Cierpka, 2008). Different findings may be attributed to the different nature of the injuries studied and the different way by which the effectiveness of ultrasound is a ssessed.Diagnosis of stress fracturesRomani and his colleagues (2001), were some of the few people who investigated the effectiveness of ultrasound therapy in the diagnosis of stress fractures. They used 1 MHz of continuous ultrasound therapy in twenty-six subjects with pain in the tibia since less than 2 weeks. Each subject completes a visual analogue scale after each different intensity was applies to assess the pain response to ultrasound. An MRI was taken to ascertain the diagnosis. However no(prenominal) of those who were found to have a stress fracture by MRI were correctly diagnosed by ultrasound.Following this review of literature, it is suggested that there may be a specific therapeutic window for ultrasound therapy. foreign results were obtained, possibly due to the different doses and frequencies used in various studies, indicating the need for further future research to identify the most effective parameters. Fortunately, none of the studies reviewed mentioned any nega tive effects on patients, making ultrasound a relatively safe modality when precautions are taken, and thus would make an important physiotherapy modality if its use is justified.