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Robert P. Nirschl - One of the best experts on this subject based on the ideXlab platform.
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Mini-open Surgery for Lateral and Medial Epicondylitis (Tendinosis)
Tennis Elbow, 2015Co-Authors: Robert P. NirschlAbstract:The term Tendinosis is preferred to epicondylitis as this is more descriptive of the true pathology. Epicondylitis (Tendinosis) occurs at least five times more commonly on the lateral than on the medial aspect of the joint. The selection factors to determine the candidates for surgery are similar for each process, yet there are some distinct features with regard to the surgical technique. Thus, medial epicondylitis is discussed separately in this chapter.
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nirschl surgical technique for concomitant lateral and medial elbow Tendinosis a retrospective review of 53 elbows with a mean follow up of 11 7 years
American Journal of Sports Medicine, 2011Co-Authors: Oliver N Schipper, Jonathan H Dunn, Derek Ochiai, Skye J Donovan, Robert P. NirschlAbstract:Background: Combined lateral elbow Tendinosis (tennis elbow) and medial elbow Tendinosis (golfer’s elbow) can be a disabling condition that, if unresponsive to nonoperative treatments, may be effectively treated surgically. The authors are not aware of any study that reports the outcome of a combined operation for lateral and medial elbow Tendinosis (country club elbow) performed in the same operative setting.Hypothesis: Combined surgical treatment of country club elbow in the same operative setting has similar outcomes to those seen in the literature for single operative procedures.Study Design: Case series; Level of evidence 4.Methods: Outcome measurements included the Numeric Pain Intensity Scale, the Nirschl tennis elbow scoring system, and the American Shoulder and Elbow Surgeons elbow form. Forty-eight patients (53 clinical elbows) were available by telephone, with a minimum time to follow-up of 5 years (range, 5-19 years; mean, 11.7 years).Results: The average Nirschl tennis elbow score improved fr...
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Tennis elbow Tendinosis (epicondylitis).
Instructional course lectures, 2004Co-Authors: Robert P. Nirschl, Edward S AshmanAbstract:Tennis elbow Tendinosis (epicondylitis) is most commonly caused by tendon overuse and failed tendon healing. The pathoanatomy of overuse tendinopathy is noninflammatory "angiofibroblastic Tendinosis." The specific areas of elbow abnormality include the extensor carpi radialis brevis-extensor digitorum communis complex laterally, the pronator teres, flexor carpi radialis medially, and triceps posteriorly. The primary goal of nonsurgical treatment is to revitalize the unhealthy tissue that produces pain. Successful nonsurgical treatment comprises rehabilitative resistance exercise and progression of the exercise program. If rehabilitation fails, surgical treatment can be quite successful.
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elbow tendinopathy tennis elbow
Clinics in Sports Medicine, 2003Co-Authors: Robert P. Nirschl, Edward S AshmanAbstract:The pathoanatomy of overuse tendinopathy is noninflammatory angiofibroblastic Tendinosis. The areas of elbow abnormality are specific, including the extensor carpi radialis brevis (ECRB) and extensor digitorum communis (EDC) complex laterally, the pronator teres, flexor carpi radialis medially, and triceps posteriorly. The goals of nonoperative treatment are to revitalize the unhealthy, pain-producing Tendinosis tissue. The key to nonoperative treatment is rehabilitative resistance exercise with progression of the exercise program. If rehabilitation fails, the surgical interventions as described are highly successful.
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current concepts review Tendinosis of the elbow tennis elbow clinical features and findings of histological immunohistochemical and electron microscopy studies
Journal of Bone and Joint Surgery American Volume, 1999Co-Authors: Barry S Kraushaar, Robert P. NirschlAbstract:Tendon injuries can be divided into several categories on the basis of the nature of their onset and the tissues involved. Acute tendon injuries, such as laceration of the flexor tendons of the fingers, are traumatic in nature. Chronic overuse injuries are the result of multiple microtraumatic events that cause disruption of the internal structure of the tendon and degeneration of the cells and matrix, which fail to mature into normal tendon; at times, such injuries result in Tendinosis35. The healing of acute tendon injuries has been studied from the perspective of the body's response to lacerations of flexor tendons as well as after operative intervention35,67. Tendinosis is incompletely understood. Although the term tendinitis is used frequently and often indiscriminately, histopathological studies have shown that specimens of tendon obtained from areas of chronic overuse do not contain large numbers of macrophages, lymphocytes, or neutrophils26,35,59. Rather, Tendinosis appears to be a degenerative process that is characterized by the presence of dense populations of fibroblasts, vascular hyperplasia, and disorganized collagen. This constellation of findings has been termed angiofibroblastic hyperplasia48. It is not clear why Tendinosis is painful, given the absence of acute inflammatory cells, nor is it known why the collagen fails to mature. If it can be assumed that Tendinosis has essentially the same pathogenesis regardless of where it occurs in the body, then the examination of specimens from patients who have tennis elbow can serve as a model for the investigation of pain in other regions in which Tendinosis has been reported, such as the rotator cuff, the Achilles tendon, the patellar ligament, the adductors of the hip, the triceps, the flexors and extensors of the elbow, and the plantar fascia7,26,27 …
Sture Forsgren - One of the best experts on this subject based on the ideXlab platform.
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STUDIES ON ACHILLES Tendinosis: BILATERAL RECOVERY AFTER UNILATERAL SURGERY, AND SIMILAR HISTOPATHOLOGICAL APPEARANCES BILATERALLY
British Journal of Sports Medicine, 2013Co-Authors: Håkan Alfredson, Christoph Spang, Sture ForsgrenAbstract:It is frequently observed that midportion Achilles tendinopathy/Tendinosis occurs bilaterally. With this as a background, the outcome of unilateral operations was evaluated in 13 patients (seven males and six females) with chronic painful bilateral midportion Achilles tendinopathy (Tendinosis) (symptom duration: 6–12 months). Prolonged periods of rest did not have an effect. As surgical treatment, an ultrasound and Doppler-guided scraping procedure outside the ventral part of the tendon was performed in local anaesthesia, a method that recently has been found to be successful for patients with Achilles Tendinosis. Surgical treatment was performed only on one side, the other side being left untreated. The patients started walking on the first day after surgery, and were followed over time. In an additional part of the study, specimens from Achilles and plantaris tendons in 3 patients with bilateral Achilles Tendinosis were examined. Follow-ups showed postoperative improvement also on the non-operated side in 11/13 patients, and a final follow up after 37 (mean) months showed significant pain relief and patient satisfaction on both sides for these 11 patients. In 2/13 patients, operation on the other, initially non-operated side, was needed. Morphologically, it was found that there were similar morphological characteristics and similar immunohistochemical patterns concerning enzymes involved in signal substance production bilaterally, the microscopic findings being in line with previous information from Tendinosis tendons. It can be concluded that the structural affections are similar on both sides in bilateral Achilles Tendinosis. The study showed that unilateral operative treatment can also have benefits contra-laterally. A hypothesis is that unilateral influences on the sensory innervation in the peritendinous tissue in response to the scraping operation have secondary effects contralaterally, that is, influences on the pattern of primary-afferent activation on one side can have effects contra-laterally. The interpretation concerning a presumable cross-talk between right and left sides are in line with the results of recent experimental studies in animals showing that Tendinosis-like features occur bilaterally in the Achilles tendons in response to unilateral overuse, suggesting that there is an involvement of central neuronal mechanisms. The observations of bilateral effects in response to unilateral treatment have clinical implications.
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The plantaris tendon in association with mid-portion Achilles Tendinosis: Tendinosis-like morphological features and presence of a non-neuronal cholinergic system.
Histology and histopathology, 2013Co-Authors: Christoph Spang, Håkan Alfredson, Mark Ferguson, Beverley Roos, Johan Bagge, Sture ForsgrenAbstract:The plantaris tendon is often neglected in morphological/clinical studies on the lower extremity. There is, however, clinical evidence that the plantaris tendon is involved in cases with Achilles midportion tendinopathy/Tendinosis. It is nevertheless unclear if the plantaris tendon exhibits Tendinosis-like features in this situation. We therefore investigated the plantaris tendon of patients with midportion Achilles Tendinosis when the plantaris tendon was found to be located very close to or invaginated into the Achilles tendon, a situation which very often has been found to be the case. There was a very large number of tenocytes in the tendon tissue and the tenocytes showed abnormal and irregular appearances, exhibiting widened/rounded and wavy appearances, and were frequently lined up in rows. These features are characteristic features in Achilles Tendinosis tendons. The tendon cells showed a distinct immunoreaction for the acetylcholine (ACh) -producing enzyme choline acetyltransferase (ChAT). Frequent fibroblasts were found in the loose connective tissue and these cells also showed a marked ChAT immunoreaction. The study shows that the plantaris tendon is morphologically affected in a similar way to the Achilles tendon in cases with midportion Achilles Tendinosis and medial pain. The plantaris tendon may accordingly be a co-factor in these cases. The results also favour that there is a local ACh production both within the tendon tissue of the plantaris tendon and in the loose connective tissue. In conclusion, it is evident that plantaris tendons lying invaginated into or very close to the Achilles tendon in cases with midportion Achilles Tendinosis show similar Tendinosis features, as previously shown for the Achilles tendon itself in these cases.
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In mid-portion Achilles Tendinosis the plantaris tendon shows the same Tendinosis-like morphological features and expression of the non-neuronal cholinergic system as the Achilles tendon itself
Experimental pathology, 2013Co-Authors: Sture Forsgren, Christoph Spang, Håkan AlfredsonAbstract:In mid-portion Achilles Tendinosis the plantaris tendon shows the same Tendinosis-like morphological features and expression of the non-neuronal cholinergic system as the Achilles tendon itself
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unexpected presence of the neurotrophins ngf and bdnf and the neurotrophin receptor p75 in the tendon cells of the human achilles tendon
Histology and Histopathology, 2009Co-Authors: Johan Bagge, Håkan Alfredson, Ronny Lorentzon, Sture ForsgrenAbstract:Neurotrophins are substances that have been shown to be important in growth and remodelling phases in different types of tissue. There is no information concerning the possible occurrences of neurotrophins and their receptors in tendons. In this study, sections of both chronic painful (Tendinosis) and pain-free (non-Tendinosis) human Achilles tendons were immunohistochemically stained with antibodies against the neurotrophins NGF and BDNF, and their receptors TrkA, TrkB and p75. There were marked immunoreactions for NGF and BDNF in the tendon cells (tenocytes) of both Tendinosis and non-Tendinosis specimens. The tenocytes were also reactive for the receptor p75, but not for the receptors TrkA and TrkB. In addition, p75 immunoreactions were seen in nerve fascicles and in the walls of arterioles. This is the first study to identify neurotrophins in the tenocytes of human tendon. It is clear from this study that the local cells of tendons are sources of neurotrophins. The neurotrophins may play an important role in the tendon through their interaction with the receptor p75 in the tenocytes. These interactions may regulate tropic modulatory, and apoptotic effects. In conclusion, the observations show a new concept concerning production and function of neurotrophins, namely in the tenocytes of tendons.
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Presence of a non-neuronal cholinergic system and occurrence of up- and down-regulation in expression of M2 muscarinic acetylcholine receptors: new aspects of importance regarding Achilles tendon Tendinosis (tendinopathy)
Cell and Tissue Research, 2008Co-Authors: Dennis Bjur, Håkan Alfredson, Patrik Danielson, Sture ForsgrenAbstract:Limited information is available concerning the existence of a cholinergic system in the human Achilles tendon. We have studied pain-free normal Achilles tendons and chronically painful Achilles Tendinosis tendons with regard to immunohistochemical expression patterns of the M_2 muscarinic acetylcholine receptor (M_2R), choline acetyltransferase (ChAT), and vesicular acetylcholine transporter (VAChT). M_2R immunoreactivity was detected in the walls of blood vessels. As evidenced via parallel staining for CD31 and alpha-smooth muscle actin, most M_2R immunoreactivity was present in the endothelium. M_2R immunoreactivity also occured in tenocytes, which regularly immunoreact for vimentin. The degree of M_2R immunoreactivity was highly variable, Tendinosis tendons that exhibit hypercellularity and hypervascularity showing the highest levels of immunostaining. Immunoreaction for ChAT and VAChT was detected in tenocytes in Tendinosis specimens, particularly in aberrant cells. In situ hybridization revealed that mRNA for ChAT is present in tenocytes in Tendinosis specimens. Our results suggest that autocrine/paracrine effects occur concerning the tenocytes in Tendinosis. Up-regulation/down-regulation in the levels of M_2R immunoreactivity possibly take place in tenocytes and blood vessel cells during the various stages of Tendinosis. The presumed local production of acetylcholine (ACh), as evidenced by immunoreactivity for ChAT and VAChT and the detection of ChAT mRNA, appears to evolve in response to Tendinosis. These observations are of importance because of the well-known vasoactive, trophic, and pain-modulating effects that ACh is known to have and do unexpectedly establish the presence of a non-neuronal cholinergic system in the Achilles tendon.
Håkan Alfredson - One of the best experts on this subject based on the ideXlab platform.
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alpha 2 adrenergic stimulation triggers achilles tenocyte hypercellularity comparison between two model systems
Scandinavian Journal of Medicine & Science in Sports, 2013Co-Authors: Ludvig J Backman, Alex Scott, Håkan Alfredson, Gloria Fong, Gustav Andersson, Patrik DanielsonAbstract:The histopathology of tendons with painful tendinopathy is often Tendinosis, a fibrosis-like condition of unclear pathogenesis characterized by tissue changes including hypercellularity. The primary tendon cells (tenocytes) have been shown to express adrenoreceptors (mainly alpha-2A) as well as markers of catecholamine production, particularly in Tendinosis. It is known that adrenergic stimulation can induce proliferation in other cells. The present study investigated the effects of an exogenously administered alpha-2 adrenergic agonist in an established in vivo Achilles Tendinosis model (rabbit) and also in an in vitro human tendon cell culture model. The catecholamine producing enzyme tyrosine hydroxylase and the alpha-2A-adrenoreceptor (α2A AR) were expressed by tenocytes, and alpha-2 adrenergic stimulation had a proliferative effect on these cells, in both models. The proliferation was inhibited by administration of an α2A AR antagonist, and the in vitro model further showed that the proliferative alpha-2A effect was mediated via a mitogenic cell signaling pathway involving phosphorylation of extracellular-signal-regulated kinases 1 and 2. The results indicate that catecholamines produced by tenocytes in Tendinosis might contribute to the proliferative nature of the pathology through stimulation of the α2A AR, pointing to a novel target for future therapies. The study furthermore shows that animal models are not necessarily required for all aspects of this research.
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STUDIES ON ACHILLES Tendinosis: BILATERAL RECOVERY AFTER UNILATERAL SURGERY, AND SIMILAR HISTOPATHOLOGICAL APPEARANCES BILATERALLY
British Journal of Sports Medicine, 2013Co-Authors: Håkan Alfredson, Christoph Spang, Sture ForsgrenAbstract:It is frequently observed that midportion Achilles tendinopathy/Tendinosis occurs bilaterally. With this as a background, the outcome of unilateral operations was evaluated in 13 patients (seven males and six females) with chronic painful bilateral midportion Achilles tendinopathy (Tendinosis) (symptom duration: 6–12 months). Prolonged periods of rest did not have an effect. As surgical treatment, an ultrasound and Doppler-guided scraping procedure outside the ventral part of the tendon was performed in local anaesthesia, a method that recently has been found to be successful for patients with Achilles Tendinosis. Surgical treatment was performed only on one side, the other side being left untreated. The patients started walking on the first day after surgery, and were followed over time. In an additional part of the study, specimens from Achilles and plantaris tendons in 3 patients with bilateral Achilles Tendinosis were examined. Follow-ups showed postoperative improvement also on the non-operated side in 11/13 patients, and a final follow up after 37 (mean) months showed significant pain relief and patient satisfaction on both sides for these 11 patients. In 2/13 patients, operation on the other, initially non-operated side, was needed. Morphologically, it was found that there were similar morphological characteristics and similar immunohistochemical patterns concerning enzymes involved in signal substance production bilaterally, the microscopic findings being in line with previous information from Tendinosis tendons. It can be concluded that the structural affections are similar on both sides in bilateral Achilles Tendinosis. The study showed that unilateral operative treatment can also have benefits contra-laterally. A hypothesis is that unilateral influences on the sensory innervation in the peritendinous tissue in response to the scraping operation have secondary effects contralaterally, that is, influences on the pattern of primary-afferent activation on one side can have effects contra-laterally. The interpretation concerning a presumable cross-talk between right and left sides are in line with the results of recent experimental studies in animals showing that Tendinosis-like features occur bilaterally in the Achilles tendons in response to unilateral overuse, suggesting that there is an involvement of central neuronal mechanisms. The observations of bilateral effects in response to unilateral treatment have clinical implications.
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The plantaris tendon in association with mid-portion Achilles Tendinosis: Tendinosis-like morphological features and presence of a non-neuronal cholinergic system.
Histology and histopathology, 2013Co-Authors: Christoph Spang, Håkan Alfredson, Mark Ferguson, Beverley Roos, Johan Bagge, Sture ForsgrenAbstract:The plantaris tendon is often neglected in morphological/clinical studies on the lower extremity. There is, however, clinical evidence that the plantaris tendon is involved in cases with Achilles midportion tendinopathy/Tendinosis. It is nevertheless unclear if the plantaris tendon exhibits Tendinosis-like features in this situation. We therefore investigated the plantaris tendon of patients with midportion Achilles Tendinosis when the plantaris tendon was found to be located very close to or invaginated into the Achilles tendon, a situation which very often has been found to be the case. There was a very large number of tenocytes in the tendon tissue and the tenocytes showed abnormal and irregular appearances, exhibiting widened/rounded and wavy appearances, and were frequently lined up in rows. These features are characteristic features in Achilles Tendinosis tendons. The tendon cells showed a distinct immunoreaction for the acetylcholine (ACh) -producing enzyme choline acetyltransferase (ChAT). Frequent fibroblasts were found in the loose connective tissue and these cells also showed a marked ChAT immunoreaction. The study shows that the plantaris tendon is morphologically affected in a similar way to the Achilles tendon in cases with midportion Achilles Tendinosis and medial pain. The plantaris tendon may accordingly be a co-factor in these cases. The results also favour that there is a local ACh production both within the tendon tissue of the plantaris tendon and in the loose connective tissue. In conclusion, it is evident that plantaris tendons lying invaginated into or very close to the Achilles tendon in cases with midportion Achilles Tendinosis show similar Tendinosis features, as previously shown for the Achilles tendon itself in these cases.
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In mid-portion Achilles Tendinosis the plantaris tendon shows the same Tendinosis-like morphological features and expression of the non-neuronal cholinergic system as the Achilles tendon itself
Experimental pathology, 2013Co-Authors: Sture Forsgren, Christoph Spang, Håkan AlfredsonAbstract:In mid-portion Achilles Tendinosis the plantaris tendon shows the same Tendinosis-like morphological features and expression of the non-neuronal cholinergic system as the Achilles tendon itself
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unexpected presence of the neurotrophins ngf and bdnf and the neurotrophin receptor p75 in the tendon cells of the human achilles tendon
Histology and Histopathology, 2009Co-Authors: Johan Bagge, Håkan Alfredson, Ronny Lorentzon, Sture ForsgrenAbstract:Neurotrophins are substances that have been shown to be important in growth and remodelling phases in different types of tissue. There is no information concerning the possible occurrences of neurotrophins and their receptors in tendons. In this study, sections of both chronic painful (Tendinosis) and pain-free (non-Tendinosis) human Achilles tendons were immunohistochemically stained with antibodies against the neurotrophins NGF and BDNF, and their receptors TrkA, TrkB and p75. There were marked immunoreactions for NGF and BDNF in the tendon cells (tenocytes) of both Tendinosis and non-Tendinosis specimens. The tenocytes were also reactive for the receptor p75, but not for the receptors TrkA and TrkB. In addition, p75 immunoreactions were seen in nerve fascicles and in the walls of arterioles. This is the first study to identify neurotrophins in the tenocytes of human tendon. It is clear from this study that the local cells of tendons are sources of neurotrophins. The neurotrophins may play an important role in the tendon through their interaction with the receptor p75 in the tenocytes. These interactions may regulate tropic modulatory, and apoptotic effects. In conclusion, the observations show a new concept concerning production and function of neurotrophins, namely in the tenocytes of tendons.
Per Aspenberg - One of the best experts on this subject based on the ideXlab platform.
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Trigger finger, Tendinosis, and intratendinous gene expression
Scandinavian journal of medicine & science in sports, 2012Co-Authors: Anna-carin Lundin, Per Aspenberg, Pernilla EliassonAbstract:The pathogenesis of trigger finger has generally been ascribed to primary changes in the first annular ligament. In contrast, we recently found histological changes in the tendons, similar to the findings in Achilles Tendinosis or tendinopathy. We therefore hypothesized that trigger finger tendons would show differences in gene expression in comparison to normal tendons in a pattern similar to what is published for Achilles Tendinosis. We performed quantitative real-time polymerase chain reaction on biopsies from finger flexor tendons, 13 trigger fingers and 13 apparently healthy control tendons, to assess the expression of 10 genes which have been described to be differently expressed in Tendinosis (collagen type 1a1, collagen 3a1, MMP-2, MMP-3, ADAMTS-5, TIMP-3, aggrecan, biglycan, decorin, and versican). In trigger finger tendons, collagen types 1a1 and 3a1, aggrecan and biglycan were all up-regulated, and MMP-3and TIMP-3 were down-regulated. These changes were statistically significant and have been previously described for Achilles Tendinosis. The remaining four genes were not significantly altered. The changes in gene expression support the hypothesis that trigger finger is a form of Tendinosis. Because trigger finger is a common condition, often treated surgically, it could provide opportunities for clinical research on Tendinosis.
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Trigger finger and Tendinosis.
The Journal of hand surgery European volume, 2011Co-Authors: Anna-carin Lundin, Pernilla Eliasson, Per AspenbergAbstract:The pathogenesis of trigger finger has generally been ascribed to primary changes in the pulley. Histological examination of the affected tendons has rarely been done. We studied biopsies from tendons of trigger fingers from 29 patients and compared these to biopsies from six intact tendons. We used a modified Movin score, which describes the Tendinosis of the Achilles tendon. Trigger finger tendons had a high score (14.2; SD, 2.2) consistent with Tendinosis, while the controls were almost normal (2.5; SD, 1.9). This suggests that the tendon is also affected, and that trigger finger is a form of Tendinosis.
Pernilla Eliasson - One of the best experts on this subject based on the ideXlab platform.
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Trigger finger, Tendinosis, and intratendinous gene expression
Scandinavian journal of medicine & science in sports, 2012Co-Authors: Anna-carin Lundin, Per Aspenberg, Pernilla EliassonAbstract:The pathogenesis of trigger finger has generally been ascribed to primary changes in the first annular ligament. In contrast, we recently found histological changes in the tendons, similar to the findings in Achilles Tendinosis or tendinopathy. We therefore hypothesized that trigger finger tendons would show differences in gene expression in comparison to normal tendons in a pattern similar to what is published for Achilles Tendinosis. We performed quantitative real-time polymerase chain reaction on biopsies from finger flexor tendons, 13 trigger fingers and 13 apparently healthy control tendons, to assess the expression of 10 genes which have been described to be differently expressed in Tendinosis (collagen type 1a1, collagen 3a1, MMP-2, MMP-3, ADAMTS-5, TIMP-3, aggrecan, biglycan, decorin, and versican). In trigger finger tendons, collagen types 1a1 and 3a1, aggrecan and biglycan were all up-regulated, and MMP-3and TIMP-3 were down-regulated. These changes were statistically significant and have been previously described for Achilles Tendinosis. The remaining four genes were not significantly altered. The changes in gene expression support the hypothesis that trigger finger is a form of Tendinosis. Because trigger finger is a common condition, often treated surgically, it could provide opportunities for clinical research on Tendinosis.
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Trigger finger and Tendinosis.
The Journal of hand surgery European volume, 2011Co-Authors: Anna-carin Lundin, Pernilla Eliasson, Per AspenbergAbstract:The pathogenesis of trigger finger has generally been ascribed to primary changes in the pulley. Histological examination of the affected tendons has rarely been done. We studied biopsies from tendons of trigger fingers from 29 patients and compared these to biopsies from six intact tendons. We used a modified Movin score, which describes the Tendinosis of the Achilles tendon. Trigger finger tendons had a high score (14.2; SD, 2.2) consistent with Tendinosis, while the controls were almost normal (2.5; SD, 1.9). This suggests that the tendon is also affected, and that trigger finger is a form of Tendinosis.
