The effects of ultrasound treatment on flexor tendon healing in the chicken limb

Effects of Low-Intensity Pulsed Ultrasound in Tendon Injuries

Tendon injuries are the most common soft tissue injuries, caused by tissue overuse and age-related degeneration. However, the tendon repair process is slow and inefficient due to the lack of cellular structure and blood vessels in the tendon. Low-intensity pulsed ultrasound (LIPUS) has received increasing attention as a non-invasive, simple, and safe way to promote tendon healing. This review summarizes the effects and underlying mechanisms of LIPUS on tendon injury by comprehensively examining the published literature, including in vitro, in vivo, and clinical studies. This review reviewed 24 studies, with 87.5% showing improvement. The application of LIPUS in tendon diseases is a promising field worthy of further study.

System and method for applying physiotherapeutic focused ultrasound

Despite many years of clinical use of ultrasound, the results of different reviews of controlled trials on the efficacy of ultrasound physical therapy for different musculoskeletal injuries continue to question its efficacy. However, "in vitro" experiments with well-controlled cell cultures and experiments with animal models show positive results. The question is whether the commercial systems used by physiotherapists can deliver the required ultrasonic dose to the exact location on the body. The object of this work is the design, realization and testing of a new concept of ultrasound system for Physiotherapy capable of focusing the ultrasound beam to apply the required ultrasonic energy dose at the point targeted by the physiotherapist. The system is designed for non-thermal effects Physiotherapy. The system consists of conceptually new piezocomposite arrays with a metallic delay line, multi-pulser electronics for emission focusing, parallel robots for mechanical steering and positioning of the array transducers, and linear and angular encoders to allow the physiotherapist to direct the focus to the target. The multi-pulser and parallel robot angulation are controlled by the computer, using a graphical interface software.

Extracorporeal shock wave therapy vs cryoultrasound therapy in the treatment of chronic lateral epicondylitis. One year follow up study

BACKGROUND

the purpose of this study is to compare the therapeutic effects of extracorporeal shock wave therapy (ESWT) to those of cryoultrasound (Cryo-US) therapy in chronic lateral epicondylitis during a 12-month period.

METHODS

single-blinded, randomized, controlled study of 80 participants treated for chronic LE with 3 ESWT sessions at 48/72-hours intervals (n=40) or 12 Cryo-US therapy sessions (4 sessions per week) (n=40). VAS and satisfactory results, considered as the sum of excellent and good scores in the Roles and Maudsley score, were used as outcome measures at baseline and 3, 6 and 12 months post-treatment.

RESULTS

the results show statistically significant differences in VAS between the two groups at 6 (p<0.001) and 12 months (p<0.001) in favour of the ESWT Group. At 12 months, a difference of more than 2 points in the VAS between the two groups is demonstrated in favour of the ESWT Group. Considering satisfactory results, significant differences between the two groups are observed at 6 (p=0.003) and 12 months (p <0.001) in favour of the ESWT Group where patients achieve a satisfactory rate over 50%.

CONCLUSIONS

ESWT has better clinical therapeutic results at 6- and 12-month follow-up as compared to Cryo-US therapy.

LEVEL OF EVIDENCE

1B.

Outcome of low level lasers versus ultrasonic therapy in de Quervain's tenosynovitis

BACKGROUND

de Quervain's tenosynovitis is an inflammation of abductor pollicis longus (APL) and extensor pollicis brevis (EPB) muscle tendon sheaths at the level of radial styloid process. Its conservative management includes nonsteroidal anti-inflammatory drugs, wrist and thumb immobilization, ultrasonic therapy (US Th.) and low level laser therapy (LLLT). Literature is scanty on comparative efficacy of US Th. and LLLT for its management. This prospective study evaluates outcome of US Th. versus LLLT in de Quervain's disease.

MATERIALS AND METHODS

Thirty patients clinically diagnosed de Quervains tenosynovitis were included in the study and randomly assigned to two groups. The average age was 36 years (range: 21-45 years). One group was given LLLT and the other US Th. for a total of 7 exposures on alternate days. The clinical criteria used were Finkelstein's test, tenderness over radial styloid (Ritchie's tenderness scale), grip strength, pain (visual analog scale [VAS]) and radiological criteria was ultrasonographic assessment of change in thickness of APL and EPB tendon sheath. They were measured before commencement and at the end of seven sessions of therapy, as per standard procedure.

RESULTS

Significant improvement was seen within both groups in the following outcome measures assessed: Ritchie's tenderness scale, grip strength and VAS. Finkelstein's test was not significantly improved in either groups. Ultrasonographic measurement of tendon sheath diameters, the mediolateral (ML), and anteroposterior (AP) diameters was not found to be significantly different in the US Th. group and the laser therapy group after treatment. On comparing both the groups, no statistically significant difference was found. However, looking at the mean values, the grip strength and VAS showed better improvement in the US Th. group as compared to the laser therapy group.

Early ultrasound therapy for rehabilitation after zone II flexor tendon repair

BACKGROUND

In our Institute, most of the patients treated for hand injuries were industrial workers with poor compliance. For rehabilitation after zone II flexor tendon repair, we had tried various early mobilization protocols. As these protocols demanded a degree of commitment from the patients, our results were suboptimal. Hence, to improve the results, we implemented a new rehabilitation protocol by administering the pulsed ultrasound therapy during the early phase of tendon healing.

MATERIALS AND METHODS

This is a prospective study done over a period of five years from January 2008 to January 2013. A total of 100 patients and 139 digits with zone II flexor tendon injuries were studied. After randomization, we administered pulsed ultrasound therapy of different frequencies and intensities for a total of 72 patients and 99 digits and formulated three groups. The results of ultrasound treated cases were compared with each other and with the results of cases treated by immobilization protocol. The results were analyzed using 'Original Strickland' criteria.

RESULTS

72% excellent-good results in ultrasound (Group 1) protocol, 75% excellent-good results in ultrasound (Group 2) protocol, and 77% excellent-good results in ultrasound (Group 3) protocol were achieved. There was no case of rupture in the first two groups. The rupture rate was 7% in ultrasound (Group 3) protocol. Only 25% excellent-good results were obtained in the immobilization protocol.

CONCLUSION

After zone II flexor tendon repair, pulsed ultrasound therapy during the early rehabilitation phase is safe and effective. The results are comparable to early mobilization protocols.

A prospective series of patients with chronic Achilles tendinopathy treated with autologous-conditioned plasma injections combined with exercise and therapeutic ultrasonography

Chronic Achilles tendinopathy is a difficult problem to manage, because it can result in significant patient morbidity. We conducted a prospective case series involving 26 patients (2 bilateral cases) with painful and ultrasound-confirmed Achilles tendinopathy for a minimum duration of 6 months. Our objective was to assess whether this condition can be effectively treated with a treatment protocol combining an intratendinous autologous-conditioned plasma injection followed by a standardized rehabilitation protocol. The rehabilitation protocol consisted of full weightbearing in a pneumatic cast boot for 6 weeks, therapeutic ultrasound treatment, and an eccentric exercise program. Our results showed statistically significant improvements in terms of pain (p < .0001), other symptoms (p = .0003), activities of daily living (p = .0002), sports activities (p = .0001), and quality of life (p = .0002). We believe that the use of autologous-conditioned plasma can provide a potential treatment solution for chronic Achilles tendinopathy.

[Flexor tendon surgery: advances in the field of hand surgery]

Reconstruction of the flexor tendon injuries is one of the most difficult problems in hand surgery, because the postoperative end-results are often unfavorable. The author discusses the history of the flexor tendon surgery, and then he describes the development of the knowledge regarding the anatomy, the blood supply and the tendon healing of the flexor tendons from the beginning until now. After that he describes the development in suture materials, suture techniques, primary and secondary tendon reconstruction operations, postoperative treatment and rehabilitation programmes. The author describes what kind of progress to be expected in this field in the near future, and then he expresses his viewpoint about the development in the international and national hand surgical societies. He encloses a detailed list of literature for those who are interested in the field.

Low-intensity pulsed ultrasound accelerates healing in rat calcaneus tendon injuries

STUDY DESIGN

Controlled laboratory study.

OBJECTIVE

To evaluate the effect of low-intensity therapeutic ultrasound on the murine calcaneus tendon healing process.

BACKGROUND

Therapeutic ultrasound promotes formation and maturation of scar tissue.

METHODS

Calcaneus tendon tenotomy and tenorrhaphy was performed on 28 Wistar rats. After the procedure, the animals were randomly divided into 2 groups. The animals in the experimental group received a 5-minute ultrasound application, once a day, at a frequency of 1 MHz, a spatial average temporal average intensity of 0.1 W/cm2, and a spatial average intensity of 0.52 W/cm2 at a 16-Hz frequency pulse mode (duty cycle, 20%). Data for the injured side were normalized in relation to the data from the contralateral healthy calcaneus tendon (relative values). The animals in the control group received sham treatment. After a 28-day treatment period, the animals were sacrificed and their tendons surgically removed and subjected to mechanical stress testing. The parameters analyzed were cross-sectional area (mm2), ultimate load (N), tensile strength (MPa), and energy absorption (mJ).

RESULTS

A significant difference between groups was found for the relative values of ultimate load and tensile strength. The mean ± SD ultimate load of the control group was -3.5% ± 32.2% compared to 33.3% ± 26.8% for the experimental group (P = .005). The mean tensile strength of the control group was -47.7% ± 19.5% compared to -28.1% ± 24.1% for the experimental group (P = .019). No significant difference was found in cross-sectional area and energy absorption.

CONCLUSION

Low-intensity pulsed ultrasound produced by a conventional therapeutic ultrasound unit can positively influence the calcaneus tendon healing process in rats.

Efeitos do ultra-som terapêutico sobre o crescimento longitudinal do fêmur e da tíbia em ratos

OBJETIVO: Estudar efeitos do ultra-som terapêutico sobre o crescimento do fêmur e da tíbia, em ratos jovens. MÉTODO: Ratus norvegicus com quatro semanas de vida, machos, totalizando 115 animais, divididos em quatro grupos, foram submetidos ao ultra-som terapêutico (0,8 MHz, cabeçote fixo, pulso contínuo, por dez minutos, durante dez dias), na face medial do joelho direito, nas potências de 0,0 W/cm2 (grupo controle), 0,5 W/cm2 (grupo G2), 1,0 W/cm2 (grupo G3), e 1,5 W/cm2 (grupo G4). Lâminas histológicas da epífise, placa de crescimento e metáfise e as medidas dos comprimentos do fêmur e da tíbia foram estudadas na sexta, décima terceira e vigésima sexta semanas de vida. Os dados foram submetidos à análise de variância - fatorial inteiramente aleatorizado. RESULTADO: Nenhuma alteração estatística do crescimento ósseo foi estabelecida entre quaisquer dos três grupos tratados e o grupo controle. Entretanto, alterações sugestivas de diminuição do crescimento do fêmur e da tíbia de G4 em relação a G2 e G3, foram evidenciadas. No grupo G4 alterações histopatológicas como necroses celulares e neoformação óssea, pós-necrose, foram encontradas. CONCLUSÃO: Quando comparados os grupos tratados com o grupo controle, não há evidência estatística de estímulo ou inibição ao crescimento ósseo pela aplicação do ultra-som terapêutico. Nível de Evidência: Nível II, estudo coorte transversal.

Comparative study of the topical application of Aloe vera gel, therapeutic ultrasound and phonophoresis on the tissue repair in collagenase-induced rat tendinitis

The aim of our study was to compare topical use of Aloe vera gel, pulsed mode ultrasound (US) and Aloe vera phonophoresis on rat paw with collagenase-induced tendinitis. Edema size, tensile tendon strength, tendon elasticity, number of inflammatory cells and tissue histology were studied at 7 and 14 days after tendinitis induction. Pulse mode US parameters were: 1 MHz frequency, 100 Hz repetition rate, 10% duty cycle, and 0.5 W/cm(2) intensity, applied for 2 min each session. A 0.5 mL of Aloe vera gel at 2% concentration was applied for 2 min per session, topically and by phonophoresis. Topical application of Aloe vera gel did not show any statistically significant improvement in the inflammatory process, whereas phonophoresis enhanced the gel action reducing edema and number of inflammatory cells, promoting the rearrangement of collagen fibers and promoting also the recovery of the tensile strength and elasticity of the inflamed tendon to recover their normal pre-injury status. Results seem to indicate that Aloe vera phonophoresis is a promising technique for tendinitis treatment, without the adverse effect provoked by systemic anti-inflammatory drugs.

Eletroacupuntura no reparo do tendão calcanear comum em coelhos após enxertia com peritônio bovino

Avaliou-se o efeito da eletroacupuntura (EA) sobre os aspectos macroscópicos e microscópicos em 36 coelhos que tiveram o tendão calcanear comum seccionado e que, após 30 dias, receberam enxerto de peritônio bovino conservado em solução saturada de sal. Após a cirurgia, os animais foram distribuídos em três grupos de igual número: os do grupo E10 foram estimulados pela EA do segundo ao 11º dia de pós-operatório, os do grupo E20 do 11º ao 31º dia de pós-operatório e os do grupo C não foram estimulados. Posteriormente, os animais foram redistribuídos em três subgrupos de igual número, os quais foram observados no pós-operatório por 11, 31 e 91 dias. Nos coelhos do E10 e E20, ocorreu diminuição de aderência da área enxertada aos tecidos circunvizinhos. Aos 31 dias de pós-operatório, observou-se nos do E10 tecido conjuntivo. Verificou-se intensa neovascularização no local enxertado em todos os animais que receberam estímulo pela EA. Nos coelhos do E10, aos 91 dias, verificou-se intensa quantidade de tecido conjuntivo, com fibras colágenas organizadas e paralelas ao eixo do tendão. O estímulo pela EA na fase precoce do pós-operatório estimulou a maturação cicatricial com mínima reação inflamatória.

O ultra-som terapêutico não aumentou as propriedades mecânicas de tendões flexores após reparo

OBJETIVO: Estudo experimental idealizado para investigar as propriedades mecânicas de tendões flexores profundos de coelhos submetidos à tenotomia seguida de tenorrafia e aplicação precoce de ultra-som terapêutico com diferentes intensidades, em comparação com tendões submetidos somente à tenorrafia. MATERIAL E MÉTODOS: Quarenta e quatro coelhos foram divididos em quatro grupos experimentais de acordo com a aplicação do ultra-som. Todos foram submetidos a uma secção do tendão flexor profundo na zona 2 e imobilizados com uma órtese mantida durante todo o experimento. O grupo A recebeu tratamento ultra-sônico com uma intensidade de 1,4 W/cm², o grupo B com 0,6 W/cm², ambos no modo contínuo, o grupo C com 0,6 W/cm² SATA, no modo pulsado à 50% e o grupo D não recebeu tratamento ultra-sônico algum. A frequência ultra-sônica empregada foi de 1 MHz. Após a eutanásia os tendões foram dissecados e submetidos ao ensaio mecânico de tração e análise histológica qualitativa. As propriedades mecânicas avaliadas foram: força máxima, deformação na força máxima e rigidez. RESULTADO: Não houve diferença estatisticamente significante entre os grupos experimentais. CONCLUSÃO: O ultra-som terapêutico não melhorou as propriedades mecânicas dos tendões flexores após reparo.

Effects of phonophoresis with Arnica montana onto acute inflammatory process in rat skeletal muscles: an experimental study

This study aimed at verifying the effects of phonophoresis associated with Arnica montana on the acute phase of an inflammatory muscle lesion. Forty Wistar male rats (300+/-50 g), of which the Tibialis Anterior muscle was surgically lesioned, were divided into four groups (n=10 each): control group received no treatment; the ultrasound group (US) was treated in pulsed mode with 1-MHz frequency, 0.5 W/cm(2) intensity (spatial and temporal average - SATA), duty cycle of 1:2 (2 ms on, 4 ms off, 50%), time of application 3 min per session, one session per day, for 3 days; the phonophoresis or ultrasound plus arnica (US+A) group was treated with arnica with the same US parameters plus arnica gel; and the arnica group (A) was submitted to massage with arnica gel, also for 3 min, once a day, for 3 days. Treatment started 24h after the surgical lesion. On the 4th day after lesion creation, animals were sacrificed and sections of the lesioned, inflamed muscle were removed for quantitative (mononuclear and polymorphonuclear cell count) and qualitative histological analysis. Collected data from the 4 groups were statistically analyzed and the significance level set at p<0.05. Results show higher mononuclear cell density in all three treated groups with no significant difference between them, but values were significantly different (p<0.0001) when compared to control group's. As to polymorphonuclear cell density, significant differences were found between control group (p=0.0134) and US, US+A and A groups; the arnica group presented lesser density of polymorphonuclear cells when compared (p=0.0134) to the other groups. No significant difference was found between US and US+A groups. While the massage with arnica gel proved to be an effective anti-inflammatory on acute muscle lesion in topic use, these results point to ineffectiveness of Arnica montana phonophoresis, US having seemingly checked or minimized its anti-inflammatory effect.

The effects of LIPUS on soft-tissue healing: a review of literature

INTRODUCTION

Ultrasound is widely used for imaging purposes and as an adjunct to physiotherapy. Low-intensity pulsed ultrasound (LIPUS), having removed the thermal component found at higher intensities, is used to improve bone healing. However, its potential role in soft-tissue healing is still under investigation.

MATERIAL AND METHODS

We searched on Medline using the keywords: low-intensity pulsed ultrasound, LIPUS and LIPUS and soft-tissue healing. Thirty-two suitable articles were identified.

RESULTS

Research, mainly pre-clinical, so far has shown encouraging result, with LIPUS able to promote healing in various soft tissues such as cartilage, inter-vertebral disc, etc. The effect on the bone-tendon junction, however, is primarily on bone. The role of LIPUS in treating tendinopathies is questionable. Adequately powered human studies with standardisation of intensities and dosages of LIPUS for each target tissue are needed.

Prevention of adhesions in surgery of the flexor tendons of the hand: what is the evidence?

INTRODUCTION

Despite advances in knowledge and refinements of technique, the management of flexor tendon injuries within the digital sheath continues to present a formidable challenge. This in turn has led to a massive expansion in search of modified surgical therapies and various adjuvant therapies, which could prevent adhesion formation without compromising digital function.

SOURCES OF DATA

A search of PubMed, Medline, CINAHL and Embase databases was performed using the keywords 'tendon adhesion prevention', 'tendon healing', 'adhesion prevention in tendons' and 'adjuvants for adhesion prevention'. Studies detailing the use of surgical, pharmacological and non-pharmacological agents for adhesion prevention in digital flexor tendons were identified, and their bibliographies were thoroughly reviewed to identify further related articles. This search identified 41 studies, which investigated the use of various pharmacological agents in adhesion prevention in digital tendons.

AREAS OF AGREEMENT

There is a need to develop and utilize an optimal method for the prevention of adhesions in the flexor tendons of the hand, due to post-surgical complications.

AREAS OF CONTROVERSY

Even though there have been significant advances in the prevention of adhesions in flexor tendons, it remains to be proved which, if any, of the current methods are the most beneficial.

GROWING POINTS

The only thing that appears clinically justified in adhesion prevention is the need for early post-operative mobilization of digits after tendon injury or repair but the best method of mobilization remains controversial.

AREAS TIMELY FOR DEVELOPING RESEARCH

Suggested changes in surgical techniques and various proposed pharmacological and non-pharmacological modalities need to withstand the test of adequately powered human trials, before their justification for potential benefit in clinical practice is accepted.

Effect of ultrasound therapy on the repair of gastrocnemius muscle injury in rats

The aim of this study was to evaluate the effect of the pulsed ultrasound therapy (PUT) in stimulating myoregeneration and collagen deposition in an experimental model of lacerative gastrocnemius muscle lesion in 30 Wistar rats. Fifteen rats were treated (TG) daily with 1 MHz pulsed ultrasound (50%) at 0.57 W/cm(2) for 5 min, and 15 were control animals (CG). Muscle samples were analyzed on postoperative days 4, 7 and 14 through H&E, Picrosirius-polarization and immunohistochemistry for desmin. The lesions presented similar inflammatory responses in both treated and control groups. The areal fraction of fibrillar collagen was larger in the TG at 4 days post-operatively (17.53+/-6.2% vs 6.79+/-1.3%, p=0.0491), 7 days (31.07+/-7.45% vs 12.57+/-3.6%, p=0.0021) and 14 days (30.39+/-7.3% vs 19.13+/-3.51%, p=0.0118); the areal fraction of myoblasts and myotubes was larger in the TG at 14 days after surgery (41.66+/-2.97% vs 34.83+/-3.08%, p=0.025). Our data suggest that the PUT increases the differentiation of muscular lineage cells, what would favor tissue regeneration. On the other hand, it is also suggested that there is a larger deposition of collagenous fibers, what could mean worse functional performance. However, the percentage of fibers seems to have stabilized at day 7 in TG and kept increasing in CG. Furthermore, the collagen supramolecular organization achieved by the TG is also significant according to the Sirius red staining results.

Análise qualitativa dos efeitos da sonoforese com Arnica montana sobre o processo inflamatório agudo do músculo esquelético de ratos

Este estudo visou verificar o efeito da sonoforese com Arnica montana sobre a fase inflamatória aguda de uma lesão muscular. Para isso, 40 ratos Wistar machos, lesados cirurgicamente, foram divididos em 4 grupos: controle (C), 10 ratos lesados e não tratados; grupo ultra-som (US), 10 lesados, tratados com US; grupo ultra-som com arnica (US+A), 10 ratos lesados, tratados com sonoforese de gel de arnica; grupo arnica (A), 10 ratos lesados, tratados com massagem de gel de arnica. O tratamento dos três grupos foi iniciado 24h após a lesão, sendo aplicado uma vez ao dia durante 3 minutos, por três dias. Quatro dias após a lesão, os animais foram sacrificados e o terço médio do músculo tibial anterior lesado foi removido e tratado histologicamente. Os resultados da análise qualitativa mostram que, no grupo C, formou-se um intenso infiltrado de células inflamatórias no espaço intersticial e um processo de regeneração apenas iniciado. Nos grupos US e US+A foi detectado um avançado processo inflamatório, com tecido conjuntivo mais organizado e consistente. No grupo A foi detectada diminuição no número de células inflamatórias e uma desorganização em sua disposição, o que poderia levar a um atraso no processo de regeneração. Conclui-se que os grupos que receberam a aplicação do ultra-som e ultra-som com arnica apresentaram semelhante aceleração do processo inflamatório agudo, sugerindo ineficácia da sonoforese quando comparada à aplicação de apenas ultra-som.

Low-intensity pulsed ultrasound on tendon healing: a study of the effect of treatment duration and treatment initiation

BACKGROUND

Low-intensity pulsed ultrasound has been reported to be effective in promoting tendon healing. However, its optimal time and duration has not yet been determined.

HYPOTHESIS

Tendons at different stages of healing may respond differently to low-intensity pulsed ultrasound. In the present study, the timing effects of low-intensity pulsed ultrasound on tendon healing were investigated in a rat model with a patellar tendon graft harvest lesion.

STUDY DESIGN

Controlled laboratory study.

METHODS

Sixty Sprague-Dawley rats underwent central third patellar tendon donor site harvest. Low-intensity pulsed ultrasound sonication was then delivered to the injured knees at day 1, 14, or 28 after harvest for 2, 4, or 6 weeks. Tendon samples were harvested at day 14, 28, and 42 after lesion for histological examination and mechanical testing.

RESULTS

A 2-week session of low-intensity pulsed ultrasound applied from day 1 postlesion (D1-2W) significantly improved the ultimate mechanical strength of the healing tendons from 23.1 +/- 8.5 MPa to 36.6 +/- 9.0 MPa. Low-intensity pulsed ultrasound did not improve healing when it was given at later stages in D15-2W and D29-2W. When low-intensity pulsed ultrasound treatment was extended from 2 weeks (D1-2W) to 4 weeks (D1-4W) or 6 weeks (D1-6W), the beneficial effects on tendon healing became insignificant. Histological examination showed that low-intensity pulsed ultrasound sonication at late healing stages may disturb remodeling with a poor collagen fiber alignment.

CONCLUSION

Low-intensity pulsed ultrasound promoted restoration of mechanical strength and collagen alignment in healing tendons only when applied at early healing stages.

CLINICAL RELEVANCE

The present findings indicate that low-intensity pulsed ultrasound may be an effective treatment to reduce tendon donor site morbidity.

Peripheral therapeutic ultrasound stimulation alters the distribution of spinal C-fos immunoreactivity induced by early or late phase of inflammation

The purpose of this investigation was to examine the central modulated effects of therapeutic ultrasound (US) on neuronal activity in the spinal cord on early and late phases of inflammation. In this study, induction of c-Fos protein, which reflects neuronal activation (particularly inflammatory nociception), was investigated in the lumbar spinal cord with immunohistochemistry. Inflammatory monoarthritis was induced in 20 male Wistar rats (weighing 250-300 g) via intra-articular injection of complete Freund's adjuvant (CFA) into the tibiotarsal joint. Two phases of arthritis, early phase (18 h after adjuvant injection) and late phase (7 d after adjuvant injection), were studied in the rats. Pulsed-mode US (1 MHz, the spatial average temporal average intensity [I(SATA)] = 0.5 W/cm(2), 50% duty cycle) was applied for 5 min. The effects of US and sham treatments against these phases of arthritis were demonstrated by spinal c-Fos-like immunoreactivity (c-Fos-LI). All data were evaluated statistically with the paired t-test or analysis of variance with Bonferroni corrections. c-Fos-LI neurons were abundant (average 264.2 +/- 11.9) in the L3 and L4 neurons of the spinal cord in areas ipsilateral to the CFA-induced arthritic leg in the early phase, but few were present (average 40.4 +/- 4.5) in the late phase in sham-treated animals. Bonferroni corrections to the alpha level were used to check the group differences in spinal c-Fos expression, and significance was reached when p < 0.025. In the early inflammatory phase, US treatment significantly suppressed the increased number of c-Fos-LI neurons associated with CFA-induced arthritis in superficial laminae, nucleus proprius, deep laminae and ventral horn of the spinal cord. However, during the late inflammatory phase, US significantly triggered c-Fos expression in most laminae, particularly in the nucleus proprius, deep laminae and ventral horn of the spinal cord. The results of our study suggest that administration of US causes a reduction of early nociceptive inflammatory processing, as shown by a decrease in CFA-induced c-Fos-LI neurons at the level of the spinal cord. In contrast, the US did not suppress, but rather enhanced, the number of c-Fos-LI neurons during the late inflammatory phase. The peripheral influences of US on the central modulation of the spinal nociceptive processing system is suggested and may reflect the work being done through the neuroplasticity of spinal cord in response to peripheral stimulation of US. Therefore, we propose a difference in spinal expression of c-Fos-LI neurons between effects of peripheral US stimulation in arthritic models that underlie early and late inflammatory pain. (E-mail: sherrie@sunrise.hk.edu.tw).

Pulsed ultrasound treatment accelerates the repair of Achilles tendon rupture in rats

A rat tenotomy model was used to investigate the effect of combined conservative management and pulsed ultrasound (PUS) on the repair of tenotomized Achilles tendon. Hemitenotomy of right medial Achilles tendon was performed in 48 rats without suture, and patella tenotomy was performed to mimic immobilization and limb disuse of an injured limb. PUS and sham PUS were applied to the healing wound for the treatment group and control group for 5 min, 3 times per week for 2 or 4 weeks, respectively. Tensile tests showed that the ultimate tensile strength (UTS) and stiffness of the repaired tendon in the treatment group at 2 weeks reached 48.92+/-8.39% and 62.48+/-32.46% of the contralateral normal tendon strength, which were significantly higher than those of the control group (UTS, 30.36+/-15.46%; stiffness, 33.90+/-17.59; p<0.05). At 4 weeks, UTS increased to 77.09+/-15.31% and stiffness to 92.48+/-31.12% in the treatment group, significantly higher than those in the control group (UTS, 54.33+/-18.40%, p<0.01; stiffness, 65.02+/-25.48%, p<0.05). Light microscopy revealed more regular, denser, and better aligned collagen fibers in the healing scar of the PUS-treated healing tendons. The findings suggested that PUS were able to accelerate the healing of the ruptured tendons.

The effect of low-intensity pulsed ultrasound on repair of epithelial cell monolayers in vitro

Low intensity pulsed ultrasound (LIPUS) is widely used to accelerate tissue regeneration following injury, but the biological mechanisms of this effect are poorly understood. An in vitro model of epithelial wound healing was used to investigate the effect of LIPUS on the reepithelialization of scrape wounds in normal human urothelial (NHU) cell monolayers. The effects of clinical doses of ultrasound treatment on NHU cell growth and migration were investigated in cells grown under optimal conditions, without growth supplements and in media containing low vs. physiological calcium concentrations. No differences in cell growth or migration were observed. We conclude that there is no direct effect upon uro-epithelial regeneration by therapeutic ultrasound in vitro and suggest that any stimulation of epithelial wound repair in vivo may occur indirectly, for example by modulating the extracellular matrix composition and/or production of paracrine factors by the stroma.

The scientific basis for advances in flexor tendon surgery

During the last 40 years, there has been an enormous amount of basic scientific research designed to improve our knowledge of the structure of tendons, the biomechanics of their action, their biologic response to injury and repair, the mechanical characteristics of various tendon suture methods, and the effect of postrepair motion stress on tendon strength and healing. These investigative efforts have given rise to improved methods of tendon repair and protocols for the early application of passive and active wrist and digital motion as a means to more rapidly increase the strength and gliding of repaired tendons. The surgical techniques of hand surgeons and the rehabilitation protocols of hand therapists have improved enormously from these scientific efforts and the results of flexor tendon repair have become much more reliable. This article attempts to review many of the important scientific reports dealing with flexor tendons that have been published during the last three-plus decades and indicate how those works have improved our management of these difficult injuries.

Diclofenac phonophoresis in human volunteers

A quantitative study of sodium diclofenac (Voltaren Emulgel, Novartis) phonophoresis was undertaken in humans. Fourteen healthy human volunteers were submitted to ultrasound irradiation on two 225-cm2 areas on the dorsum (group A), followed by the application of the medication gel, and the plasma diclofenac mass was measured at 1, 2 and 3 h later by high performance liquid chromatography. The same procedure was repeated one month later with the same volunteers but with the ultrasound equipment switched off for the control group (group B). The plasma diclofenac mass was significantly higher in group A than in group B at 1 h (0.0987 microg/mL as opposed to 0.0389 microg/mL; p=0.01) and 2 h (0.0724 microg/mL as opposed to 0.0529 microg/mL; p=0.01), but not at 3 h (0.0864 microg/mL as opposed to 0.0683 microg/mL; p=0.16). The authors conclude that previously applied therapeutic ultrasound irradiation enhances the percutaneous penetration of the topical diclofenac gel, although the mechanism remains unclear.

Comparison of the effects of laser, ultrasound, and combined laser + ultrasound treatments in experimental tendon healing

BACKGROUND AND OBJECTIVE

Therapeutic ultrasound (US) and laser (L) treatments accelerate and facilitate wound healing, and also have beneficial effects on tendon healing. This randomized control study was designed to evaluate the effects of low-intensity US and low-level laser therapy (LLLT) on tendon healing in rats.

STUDY DESIGN/MATERIALS AND METHODS

Eighty-four healthy male Swiss-Albino rats were divided into three groups consisting of 28 rats, the left Achilles tendons were used as treatment and the right Achilles tendons as controls. The right and left Achilles tendons of rats were traumatized longitudinally. The treatment was started on postinjury day one. We applied the treatment protocols including low-intensity US treatment in Group I (US Group), Sham US in Group II (SUS Group), LLLT in Group III (L Group), Sham L in Group IV (SL Group), US and LLLT in Group V (US + L Group), and Sham US and Sham L in Group VI (SUS + SL Group). The US treatment was applied with a power of 0.5 W/cm2, a frequency of 1 MHz, continuously, 5 minutes daily. A low-level Ga-As laser was applied with a 904 nm wavelength, 6 mW average power, 1 J/ cm2 dosage, 16 Hz frequency, for 1 minute duration, continuously. In the control groups, the similar procedures as in the corresponding treatment groups were applied with no current (Sham method). The treatment duration was planned for 9 days (sessions) in all groups, except the rats used for biochemical evaluation on the 4th day of treatment, which were treated for 4 days. We measured the levels of the tissue hydroxyproline for biochemical evaluation on the 4th, 10th, and 21st days following the beginning of treatment and the tendon breaking strength on the 21st day following the beginning of treatment for biomechanical evaluation. Seven rats in each group were killed on the 4th, 10th, and 21st days for biochemical evaluation and on the 21st day for biomechanical evaluation.

RESULTS

The hydroxyproline levels were found to be significantly increased in the treatment groups on the 10th and 21st days compared to their control groups (P < 0.05). In comparison of the treatment groups on the 4th, 10th, and 21st days of the treatment, the levels of tissue hydroxyproline were found to be more increased in combined US+L Group compared with US Group and L Group, but the difference was not significant (P > 0.05). In comparison of the tendon breaking strengths, it was found as significantly increased in the treatment groups compared with their control groups (P < 0.05), although there was no significant difference between the treatment groups.

CONCLUSIONS

Although US, L, and combined US + L treatments increased tendon healing biochemically and biomechanically more than the control groups, no statistically significant difference was found between them. Also we did not find significantly more cumulative positive effects of combined treatment. As a result, both of these physical modalities can be used successfully in the treatment of tendon healing.

Flexor tenolysis

Tenolysis is a well-established salvage procedure, which can be applied when non-gliding adhesions form along the surface of a tendon after injury or repair and prevent gliding of the tendon in the performance of its intended function.(8,15,17,29,30,39,40,44,49) Tendon adhesions will occur whenever the surface of a tendon is damaged either through the injury itself, be it laceration or crush, or by surgical manipulation.(18) At any point on the surface of a tendon where violation occurs, an adhesion will form in the healing period.(20,26) When these adhesions cannot be mobilised by an adequate course of hand therapy, tenolysis should be considered. This procedure is as difficult or more so than tendon repair itself and should not be undertaken lightly. It represents another surgical incursion into an area of previous trauma and surgery. If the procedure is not successful, the patient's hand may show no improvement or even be worse. The risk of further decreasing the circulatory supply and innervation to an already deprived finger is a real one. Rupture of the lysed tendon, a disastrous complication, is the major hazard of tenolysis.

Low-intensity pulsed ultrasound enhances early healing of medial collateral ligament injuries in rats

OBJECTIVE

To investigate the effect of low-intensity pulsed ultrasound exposure on the healing of injured medial collateral ligaments.

METHODS

Thirteen male Sprague Dawley rats were used in the study. After surgical transection of the bilateral medial collateral ligaments, the ligament of 1 knee received low-intensity pulsed ultrasound exposure (30 mW/cm2 for 20 minutes daily), whereas no ultrasound was applied to the contralateral knee (control side). Eight rats were killed at 12 days after surgery, and 5 rats were killed at 21 days. The bilateral knees of 5 rats were used for mechanical testing at each of the 2 periods, and 12-day specimens of the remaining 3 rats were prepared for the electron microscopic examination. The knees of 5 additional rats were used to obtain mechanical data of the normal uninjured medial collateral ligament.

RESULTS

On the 12th day, the low-intensity pulsed ultrasound-treated side exhibited significantly superior mechanical properties when compared with the control side in ultimate load, stiffness, and energy absorption (P < .05). However, the treatment did not afford any mechanical advantage when tested on the 21st day. The mean diameter of the fibril was significantly larger on the treatment side than on the control side (P < .05).

CONCLUSIONS

Low-intensity pulsed ultrasound exposure is effective for enhancing the early healing of medial collateral ligament injuries.

Continuous therapeutic ultrasound accelerates repair of contraction-induced skeletal muscle damage in rats

OBJECTIVE

To examine the effect of ultrasonography on the repair of muscle injured through repeated eccentric contractions.

DESIGN

Randomized, case-control study.

SETTING

Laboratory animal facility.

ANIMALS

Thirty-three Sprague-Dawley rats.

INTERVENTIONS

Specimens were anesthetized and each foot strapped, in turn, onto a motorized foot pedal, which moved the ankle repeatedly through a range of 110 degrees. Extensor digitorum longus muscles were injured by stimulating the peroneal nerve during foot plantarflexion. Continuous 1.0MHz ultrasound treatments at 0.5W/cm(2) were applied through water submersion technique to 1 limb daily for 3, 5, or 7 days postinjury. The contralateral limb served as an injured control.

MAIN OUTCOME MEASURES

Extensor digitorum longus maximum isometric tetanic force (P(o)) was measured in vitro from all extensor digitorum longus muscles and used as a functional index of muscle injury.

RESULTS

Analysis of variance and Tukey post hoc analysis showed no significant differences in P(o) between treated and untreated limbs at 3 and 5 days, but at 7 days postinjury, P(o) of ultrasound-treated muscle was significantly higher than was untreated muscle.

CONCLUSION

Seven days of continuous therapeutic ultrasound improved force production after contraction-induced muscle injury.

The effect of therapeutic ultrasound on repair of the achilles tendon (tendo calcaneus) of the rat

The purpose of this study was to evaluate the effects of therapeutic ultrasound (US) on the healing process in the Achilles tendon (Tendo calcaneus) of Wistar rats after tenotomy. Sonication was performed at a frequency of 1 MHz, an intensity of 0.5 W/cm(2) (SATA), for 5 min, over a period of 14 consecutive days in two modalities (n = 15); in both continuous and pulsed modes. The control group was divided into tenotomized, mock-sonicated and nontenotomized tendons (n = 15). On the 15th postoperative day, the tendons were removed and analyzed by using the polarized light microscopy, with the purpose of detecting and measuring the organization of collagen fibers through birefringence. The results showed a high birefringence for the tendons treated using the pulsed mode (p < 0.001), revealing the best organization and aggregation of collagen bundles. Sonication in the continuous mode induced a decrease (p = 0.047) in the ability to quicken the healing process. These findings suggest that US therapy is beneficial in the early healing process of tendons when the pulsed mode is used.

Therapeutic modalities in hand surgery

Therapeutic modalities are useful adjuncts in the rehabilitation of many patients commonly seen by hand surgeons. Therapeutic heat, cold, electrical stimulation, and laser and magnetic field treatments are evaluated for their respective mechanisms of action, indications, contraindications, and clinical results. The majority of therapeutic modalities have been extensively investigated and relevant basic science and randomized well-controlled clinical studies addressing the efficacy of therapeutic modalities are emphasized.

The effect of pulsed electromagnetic fields on flexor tendon healing in chickens

This study was designed as a pilot investigation of the effect of pulsed electromagnetic fields (PEMF) stimulation on early flexor tendon healing in a chicken model using a similar stimulus to that used clinically. The PEMF used caused a decrease in tensile strength and an increase in peritendinous adhesions.