Tendinopathy—from basic science to treatment

Chronic tendon pathology (tendinopathy), although common, is difficult to treat. Tendons possess a highly organized fibrillar matrix, consisting of type I collagen and various 'minor' collagens, proteoglycans and glycoproteins. The tendon matrix is maintained by the resident tenocytes, and there is evidence of a continuous process of matrix remodeling, although the rate of turnover varies at different sites. A change in remodeling activity is associated with the onset of tendinopathy. Major molecular changes include increased expression of type III collagen, fibronectin, tenascin C, aggrecan and biglycan. These changes are consistent with repair, but they might also be an adaptive response to changes in mechanical loading. Repeated minor strain is thought to be the major precipitating factor in tendinopathy, although further work is required to determine whether it is mechanical overstimulation or understimulation that leads to the change in tenocyte activity. Metalloproteinase enzymes have an important role in the tendon matrix, being responsible for the degradation of collagen and proteoglycan in both healthy patients and those with disease. Metalloproteinases that show increased expression in painful tendinopathy include ADAM (a disintegrin and metalloproteinase)-12 and MMP (matrix metalloproteinase)-23. The role of these enzymes in tendon pathology is unknown, and further work is required to identify novel and specific molecular targets for therapy

A systematic review with procedural assessments and meta-analysis of Low Level Laser Therapy in lateral elbow tendinopathy (tennis elbow)

<p>Abstract</p> <p>Background</p> <p>Recent reviews have indicated that low level level laser therapy (LLLT) is ineffective in lateral elbow tendinopathy (LET) without assessing validity of treatment procedures and doses or the influence of prior steroid injections.</p> <p>Methods</p> <p>Systematic review with meta-analysis, with primary outcome measures of pain relief and/or global improvement and subgroup analyses of methodological quality, wavelengths and treatment procedures.</p> <p>Results</p> <p>18 randomised placebo-controlled trials (RCTs) were identified with 13 RCTs (730 patients) meeting the criteria for meta-analysis. 12 RCTs satisfied half or more of the methodological criteria. Publication bias was detected by Egger's graphical test, which showed a negative direction of bias. Ten of the trials included patients with poor prognosis caused by failed steroid injections or other treatment failures, or long symptom duration or severe baseline pain. The weighted mean difference (WMD) for pain relief was 10.2 mm [95% CI: 3.0 to 17.5] and the RR for global improvement was 1.36 [1.16 to 1.60]. Trials which targeted acupuncture points reported negative results, as did trials with wavelengths 820, 830 and 1064 nm. In a subgroup of five trials with 904 nm lasers and one trial with 632 nm wavelength where the lateral elbow tendon insertions were directly irradiated, WMD for pain relief was 17.2 mm [95% CI: 8.5 to 25.9] and 14.0 mm [95% CI: 7.4 to 20.6] respectively, while RR for global pain improvement was only reported for 904 nm at 1.53 [95% CI: 1.28 to 1.83]. LLLT doses in this subgroup ranged between 0.5 and 7.2 Joules. Secondary outcome measures of painfree grip strength, pain pressure threshold, sick leave and follow-up data from 3 to 8 weeks after the end of treatment, showed consistently significant results in favour of the same LLLT subgroup (p < 0.02). No serious side-effects were reported.</p> <p>Conclusion</p> <p>LLLT administered with optimal doses of 904 nm and possibly 632 nm wavelengths directly to the lateral elbow tendon insertions, seem to offer short-term pain relief and less disability in LET, both alone and in conjunction with an exercise regimen. This finding contradicts the conclusions of previous reviews which failed to assess treatment procedures, wavelengths and optimal doses.</p

Comparação do ultrassom pulsado e contínuo no reparo tendíneo de ratos Comparison of pulsed and continuous ultrasound on tendon repair in rats

No tratamento de lesões tendíneas, o uso do ultrassom surge como possibilidade terapêutica, apesar de lacunas sobre seus efeitos clínicos. O objetivo foi avaliar dois protocolos de ultrassom terapêutico sobre dor e edema após trauma tendíneo. Vinte e um ratos Wistar foram submetidos a trauma no tendão calcâneo e divididos em três grupos: sham (GS); ultrassom contínuo (GUC); e ultrassom pulsado (GUP). O trauma ocorreu sobre a face lateral do tendão calcâneo direito, com energia de 0,40 J. A dor foi avaliada pelo teste de incapacidade funcional e o edema, pelo diâmetro laterolateral. Foram realizadas avaliações previamente à lesão; após 1 hora da indução da lesão; após o 1º tratamento; 2, 8 e 24 horas após lesão; e após o 5º dia. O tratamento ocorreu em 5 dias, com transdutor de 1 MHz, durante 3 minutos, sobre o local do trauma, com dose de 0,4 W/cm² SATA. Os resultados da incapacidade funcional para GS mostraram aumento da nocicepção. Para GUC houve aumento ao comparar a avaliação 1 (AV1) com as avaliações 2 (AV2), 3 (AV3) e 4 (AV4); ao comparar AV2 com as avaliações 5 (AV5) e 6 (AV6) houve diminuição de valores. Para GUP houve aumento ao comparar AV1 com AV2 e AV3, mas ao comparar AV2 com as seguintes, houve diminuição significativa a partir de AV4. Para o edema, os grupos tratados produziram aumento inicial, com redução nas últimas avaliações. O ultrassom terapêutico produziu diminuição de dor e edema, mais precocemente para a forma pulsada.<br>In tendon injuries treatment, the use of ultrasound appears as a therapeutic option, despite the lack of their clinical effects. The aim was to evaluate two therapeutic ultrasound protocols, continuous or pulsed, on the pain and swelling after tendinous trauma. Twenty-one Wistar rats were subjected to traumatic injury in the tendon and divided in three groups: sham (GS), continuous ultrasound (GUC), and pulsed ultrasound (GUP). The injury occurred on right Achilles tendon lateral aspect, with energy of 0.40 J. The pain was assessed by the functional disability test and edema by latero-lateral diameter. The evaluations were performed before the injury; after 1 hour of the lesion induction; after the 1st treatment; 2, 8 and 24 hours after injury; and after the 5th day. The treatment was made for 5 consecutive days, with transductor of 1 MHz, for 3 minutes on the trauma site, with a dose of 0.4 W/cm² SATA. The results of functional disability for GS showed increased nociception. For GUC, there was increased when comparing evaluation 1 (EV1) with evaluations 2 (EV2), 3 (EV3) and 4 (EV4); comparing EV2 to evaluations 5 (AV5) and 6 (AV6), there was decreased values. To GUP there was increased when comparing EV1 with EV2 and EV3, but when comparing EV2 with the following, there was a significant decrease starting from EV4. Edema, treatment groups produced an initial increase with a reduction in recent evaluations. The therapeutic ultrasound produced pain and edema reduction in rats with tendon trauma, and early in the pulsed