Nitric oxide is a small free radical generated by family of enzymes, the nitric oxide synthases. In a series of experiments performed over the last 15 years we showed that nitric oxide is induced by all three isoforms of nitric oxide synthase during tendon healing and that it plays a crucial beneficial role in restoring tendon function. In normal tendon we found very little nitric oxide synthase activity while in injured rat and human tendons nitric oxide synthase activity was expressed in healing fibroblasts in a temporal fashion. In healing rat Achilles tendon fibroblasts the first isoform to be expressed was endothelial nitric oxide synthase (eNOS), followed by inducible nitric oxide synthase (iNOS), and then brain or neuronal nitric oxide synthase (bNOS). Systemic inhibition of nitric oxide synthase activity decreased the cross sectional area and mechanical properties of the healing rodent Achilles tendons. Addition of nitric oxide via NO-flurbiprofen or NO-paracetamol enhanced rat Achilles tendon healing. Addition of nitric oxide to cultured human tendon cells via chemical means and via adenoviral transfection enhanced collagen synthesis, suggesting that one mechanism for the beneficial of nitric oxide on tendon healing might be via matrix synthesis. The final part of the work involved three randomized, double-blind clinical trials which evaluated the efficacy of nitric oxide donation via a patch in the management of the tendinopathy. In all three clinical trials there was a significant positive beneficial effect of nitric oxide donation to the clinical symptoms and function of patients with Achilles tendinopathy, tennis elbow and Achilles tendonitis.

This thesis describes a series of studies in which ultrasound was used to measure muscle activity around the shoulder. The preliminary studies used professional musicians as subjects because the chronic nature of their problems with shoulder muscles offered an opportunity to test the usefulness of ultrasound in a changing physical environment. Once protocols, reliability, validity and sensitivity to change were established, the main study focused on ?normal? subjects in order to explore ?normal? variability.

The supraspinatus tendon is an important structure of the rotator cuff. Subacromial impingement is a common reason for shoulder pain. Despite extensive scientific work in this field, the cause of impingement syndrome is still not fully understood. The general aim of the present thesis was to generate new knowledge with respect to pathogenesis and treatment of impingement syndrome. A combination of animal and clinical studies were performed. Different methods were used such as histology, immunohistochemistry, development and assessment of a novel measuring device and clinical and radiological assessment. Thirty rats were injected with triamcinolone or saline into the subacromial bursa. After five corticosteroid injections, we found focal inflammation, degradation and fragmentation of collagen bundles in the supraspinatus tendon, whereas the control specimens were normal (p=0.035). Subacromial bursitis was induced by injections of carrageenan into the subacromial space (n=28). Fibrocartilaginous metaplasia and bony metaplasia were found in the supraspinatus tendon. Even in specimens with no histologic changes of the collagen bundles the staining for fibronectin was significantly increased. The distance between the anterolateral acromion and the supraspinatus tendon was measured in patients with impingement syndrome intraoperatively (n=30) and in controls (instability, n=15). The mean value of the subacromial distance in controls was 16 mm, the 95% mean confidence limits between 14 and 18 mm. The mean value in the group of patients with impingement syndrome was 8 mm before and 16 mm after the decompression. Fifty patients were reviewed after arthroscopic subacromial decompression. Twenty-five showed calcific deposits in the rotator cuff on radiographs preoperatively. In 13 patients the calcific deposits totally disappeared postoperatively. In another six patients the calcifications had decreased in size. Four patients still showed calcifications, which were 5 mm or greater in size. The postoperative results measured by the Constant score were almost identical in the calcific and the non-calcific groups. Tillander 010916 8 Human surgical supraspinatus tendon specimens were studied from patients with impingement (n=16), ruptured supraspinatus tendons (n=7) and controls (n=10). Degradation of tendinous tissue and fibrin were found only in some specimens from ruptures. The difference in fibronectin staining was significant between controls and patients with a rupture (p=0.002). Fibrosis and thinning of fascicles seemed to be a more non-specific finding, appearing in control, impingement and rupture specimens. In conclusion, subacromial corticosteroid injections may cause rupture of the supraspinatus tendon. Metaplasia of the supraspinatus tendon may play a role in the pathogenesis of impingement and rupture of the supraspinatus tendon. The subacromial distance can be measured intraoperatively and was shown to be lower in patients with impingement than in patients with instability. Calcifications disappear or decrease in size after arthroscopic subacromial decompression and do not seem to influence the postoperative outcome in patients with impingement. Degradation of tendon tissue, fibrin and fibronectin appear to be signs of tendon degeneration, whereas fibrosis and thinning of fascicles were found also in controls.

Tendinopathies are painful tendon conditions of presumably multifactorial genesis. In tendinosis, as in Achilles tendinosis, there is apart from pain also morphological changes which are described as degenerative with no signs of inflammation. The exact mechanisms behind these conditions are still, to a large extent, unknown. Pain, being the foremost impairing symptom, leads us to the hypothesis that nerves are deeply involved in the symptoms and processes of Achilles tendinosis. Locally produced nerve signal substances may also be involved in the processes. Knowledge of the innervation patterns within the tendon and knowledge on a possible local nerve signal substance production are therefore of utmost importance. There is a lack of information on these aspects. The specific aims of this thesis were 1) to investigate the innervation patterns regarding general, sensory, cholinergic and sympathetic innervations, and 2) to examine for the possible occurrence of a production of nerve signal substances and a presence of receptors related to these in the tendon cells, the tenocytes. Painfree normal and tendinosis Achilles tendons were examined. Immunohistochemistry, using antibodies against the general nerve marker PGP9.5, the synthesizing enzymes for acetylcholine (choline acetyltransferase; ChAT), and catecholamines (tyrosine hydroxylase; TH), the vesicular acetylcholine transporter (VAChT), neuropeptide Y (NPY), substance P and calcitonin gene-related peptide, was applied. Immunohistochemistry was also used for the delineation of muscarinic (M2R), adrenergic (α1-AR) and NPY-ergic (Y1 and Y2) receptors. To detect mRNA for TH and ChAT, in situ hybridization was used. In normal Achilles tendons, as well as in the tendinosis tendons, there was a very scanty innervation within the tendon tissue proper, the main general, sensory and sympathetic innervations being found in the paratendinous loose connective tissue. Interestingly, the tenocytes showed immunoreactions for ChAT, VAChT, TH, M2R, α1-AR and Y1R. The reactions were clearly more observable in tendons of tendinosis patients than in those of controls. The tenocytes of tendinosis patients also displayed mRNA reactions for ChAT and TH. Nevertheless, all tenocytes in the tendinosis specimens did not show these reactions. Immunoreactions for α1-AR, M2R and Y1R were also seen for blood vessel walls. The present thesis shows that there is a very limited innervation within tendon tissue proper, whilst there is a substantial innervation in the paratendinous loose connective tissue. It also gives evidence for an occurrence of production of catecholamines and acetylcholine in tenocytes, especially for tendinosis tendons. Furthermore, that ACh, catecholamines and NPY can have effects on these, as well as on blood vessels, via the receptors observed. The observations suggest that Achilles tendon tissue, whilst containing a very scarce innervation, exhibits autocrine/paracrine cholinergic/catecholaminergic/NPY-ergic effects that are upregulated in tendinosis. These findings are of great importance as the results of such effects may mimic processes that are known to occur in tendinosis. That includes effects related to proliferation and angiogenesis, and blood vessel and collagen regulating effects. In conclusion, within the Achilles tendon there is a very scarce innervation, whilst there appears to be a marked local production of nerve signal substances in Achilles tendinosis, namely in the tenocytes, the cells also harbouring receptors for these substances. The observations give a new insight into how the tendon tissue of the Achilles tendon is influenced by signal substances and may give options for new treatments of Achilles tendinosis.

Tendinosis is a condition of chronic pain that afflicts several human tendons, not least the patellar tendon, in which case it is often clinically referred to as ‘jumper’s knee’. The exact mechanisms behind tendinosis are yet not fully understood. One draw-back in the case of patellar tendinosis has been the lack of knowledge of the innervation patterns of the human patellar tendon. It cannot be excluded that the processes of tendinosis are influenced by nerve mediators, released from nerve endings or from stimulated cells inside the tendon. Thus, the studies of the present thesis aimed to 1) map the general, sensory, cholinergic and sympathetic innervation patterns of the human patellar tendon, in both the tendon tissue proper and the loose paratendinous connective tissue surrounding the tendon, and 2) investigate the possible existence of a production of signal substances, traditionally associated with neurons, in non-neuronal tendon cells, and to see if there are signs of local cholinergic and catecholaminergic signaling pathways. Biopsies of both normal pain-free patellar tendons and patellar tendons from patients with chronic painful tendinosis were collected and investigated. The main method utilized was immunohistochemistry, using antibodies directed against synthesizing enzymes for acetylcholine and catecholamines, against muscarinic and adrenergic receptors, and against markers of general and sensory innervation. In situ hybridization (ISH) to detect mRNA for the cholinergic/catecholaminergic synthesizing enzymes was also used. It was found that the loose paratendinous connective tissue of the patellar tendon was rather richly innervated by nerve structures. These consisted of large nerve fascicles, as well as perivascular innervation in the walls of some of the larger arteries and smaller blood vessels. It was found that part of the nerve structures corresponded to sensory afferents, and that some conformed to cholinergic and, especially, sympathetic nerve fibers. The tendon tissue proper was strikingly less innervated than the paratendinous tissue. The sparse innervation that was found in the tendon tissue proper was seen in narrow zones of loose connective tissue and blood vessels, interspersed between the collagen bundles. The overall impression was that the patterns of distribution of the general, sensory, and autonomic innervations of tendinosis tendon tissue were similar to those of normal tendon tissue proper. The most pioneering findings were the immunohistochemical observations of an expression of enzymes related to production of both acetylcholine and catecholamines within the tendon cells (tenocytes) themselves, as well as of a presence of the receptors for these substances on the same cells; features that were predominantly seen in tendinosis tendons. The observations of the synthesizing enzymes for acetylcholine and catecholamines in tenocytes were confirmed by ISH findings of mRNA for these enzymes in the tenocytes. Immunoreactions for muscarinic and adrenergic receptors were also found in blood vessel walls and in some of the nerve fascicles. In summary, this thesis presents novel information on the innervation patterns of the human patellar tendon, in healthy individuals with pain-free tendons as well as in patients with chronic painful tendinosis. Furthermore, it gives the first evidence of the presence of a local, non-neuronal production in the tendon tissue of signal substances normally seen in neurons, and a basis for these substances to affect the tenocytes as these cells also display muscarinic and adrenergic receptors. Thus, the results indicate an existence of autocrine and/or paracrine cholinergic/catecholaminergic systems in the tendon tissue; systems that seem to be up-regulated in tendinosis. This is of great interest as it is known that stimulation of receptors for both catecholamines and acetylcholine can lead to cell proliferation, interfere with pain sensation, influence collagen production, and take part in vasoregulation, as well as, in the case of adrenergic receptors, promote cell degeneration and apotosis. All these processes represent biological functions/events that are reported to be affected in tendinosis. In conclusion, despite the fact that there is very limited innervation within the patellar tendon tissue proper, it is here shown that effects of signal substances traditionally associated with neurons seem to occur in the tissue, via a local production of these substances in tenocytes.

Flexor tendon injuries in zone II of the hand (i.e. between the distal volar crease and the distal interphalangeal joint) can be costly for both the afflicted individual and society because of the high cost of a long rehabilitation period, complicated by tendon ruptures or scarring with adhesion formation, causing impaired range of motion. The aim of the present thesis was to characterize more fully the deep flexor tendon, the tendon sheath and their response to injury in a rabbit model in order to find potential targets to improve the outcome of repair. The intrasynovial rabbit deep flexor tendon differed from the extrasynovial peroneus tendon in the expression of collagens and transforming growth factor-β1 gene expression. Differences were also found in collagen III and proteoglycans between regions of the flexor tendon subjected to either compressive or tensile load. After laceration and subsequent repair of the flexor tendon, a shift in collagen gene expression from type I to type III occurred. Proteoglycans were generally increased with the notable exception of decorin, a potential inhibitor of the profibrotic transforming growth factor-β1 which was markedly increased during the first two weeks after repair in tendon tissue but remained unaltered in the sheaths. Both vascular endothelial growth factor and basic fibroblast growth factor mRNA levels remained essentially unaltered, whereas insulin-like growth factor-1 increased later in the healing process, suggesting potential beneficial effects of exogenous addition, increasing tendon strength through stimulating tenocyte proliferation and collagen synthesis. Matrix metalloproteinase-13 mRNA levels increased and remained high in both tendon and sheath, whereas there was only a transient increase of matrix metalloproteinase-3 mRNA in tendon. We could also demonstrate a significant increase of the proportion of myofibroblasts, mast cells and neuropeptide containing nerve fibers in the healing tendon tissue, all components of the profibrotic myofibroblast-mast cell-neuropeptide pathway. / Biomolecular aspects of flexor tendon healing

Pain of the musculoskeletal system is one of the most common reasons for people seeking medical attention, and is also one of the major factors that prevent patients from working. Chronic tendon pain, tendinopathy, affects millions of workers world-wide, and the Achilles tendon is an important structure often afflicted by this condition. The pathogenesis of tendinopathy is poorly understood, but it is thought to be of multifactoral aetiology. It is known that tendon pain is often accompanied not only by impaired function but also by structural tissue changes, like vascular proliferation, irregular collagen organisation, and hypercellularity, whereby the condition is called tendinosis. In light of the poor knowledge of tendinosis pathophysiology and recent findings of a non-neuronal signalling system in tendon tissue, the contributory role of neuropeptides such as substance P (SP) has gained increased interest. SP, known for afferent pain signalling in the nervous system, also has multiple efferent functions and has been described to be expressed by non-neuronal cells. As pain is the most prominent symptom of tendinopathy, the focus of the studies in this thesis was the innervation patterns of the tissue ventral to the Achilles tendon (i.e. the tissue targeted in many contemporary treatment methods) as well as the distribution of SP and its preferred receptor, the neurokinin-1 receptor (NK-1R), in the tendon tissue itself. It was hereby hypothesised that the source of SP affecting the Achilles tendon might be the main cells of the tendon tissue (the tenocytes) as well as paratendinous nerves, and that SP might be involved in tendinosis- development. The studies were conducted, via morphological staining methods including immunohistochemistry and in situ hybridisation, on tendon biopsies from patients suffering from Achilles tendinosis and on those from healthy volunteers. The hypothesis of the thesis was furthermore tested using an experimental animal model (rabbit) of Achilles tendinopathy, which was first validated. The model was based on a previously established overuse protocol of repetitive exercise. In the human biopsies of the tissue ventral to the Achilles tendon, there was a marked occurrence of sympathetic innervation, but also sensory, SP-containing, nerve fibres. NK-1R was expressed on blood vessels and nerve fascicles of the paratendinous tissue, but also on the tenocytes of the tendon tissue proper itself, and notably more so in patients suffering from tendinosis. Furthermore, the human tenocytes displayed not only NK-1R mRNA but also mRNA for SP. The animal model was shown to produce objectively verified tendinosis-like changes, such as hypercellularity and increased vascularity, in the rabbit Achilles tendons, after a minimum of three weeks of the exercise protocol. The contralateral leg of the animals in the model was found to be an unreliable control, as bilateral changes occured. The model furthermore demonstrated that exogenously administered SP triggers an inflammatory response in the paratendinous tissue and accelerates the intratendinous tendinosis-like changes such that they now occur after only one week of the protocol. Injections of saline as a control showed similar results as SP concerning hypercellularity, but did not lead to vascular changes or pronounced paratendinous inflammation. In summary, this thesis concludes that interactions between the peripheral sympathetic and sensory nervous systems may occur in Achilles tendinosis at the level of the ventral paratendinous tissue, a region thought to be of great importance in chronic tendon pain since many successful treatments are directed toward it. Furthermore, the distribution of NK-1R:s in the Achilles tendon described in these studies gives a basis for SP, whether produced by nerves mainly outside the tendon or by tenocytes within the tendon, to affect blood vessels, nerve structures, and/or tendon cells, especially in tendinosis patients. In light of this and of previously known SP-effects, such as stimulation of angiogenesis, pain signalling, and cell proliferation, the proposed involvement of SP in tendinosis development seems likely. Indeed, the animal model of Achilles tendon overuse confirms that SP does induce vascular proliferation and hypercellularity in tendon tissue, thus strengthening theories of SP playing a role in tendinosis pathology.

Syfte: Sammanställa och granska studier gällande postoperativ behandling vid ruptur av ligament patella. Detta för att beskriva effekt och kvalitet på studier om postoperativ behandling. Metod: En beskrivande litteraturstudie valdes som design, med sökorden: patellar ligament, patellar tendon, rupture, knee injuries, surgery. Av totalt 1240 träffar valdes 13 relevanta artiklar publicerade mellan 1999-2013 efter sökningar i databaserna PubMed, PEDro, COCHRANE, SCOPUS, CINAHL, SPORTDiscus och AMED. Artiklarna kvalitetsgranskades enligt PEDro scale. Resultat: Två postoperativa behandlingar beskrevs, tidig och sen mobilisering. Antingen placeras knäleden i ett stabiliserande knäskydd som till en början låser knäleden i full extension eller så påbörjas tidig mobilisering av den opererade knäleden. Ingen signifikant skillnad påvisades mellan tidig och sen mobilisering vad gäller effekten på muskelstyrka, rörelseomfång och återgång till tidigare aktivitetsnivå. Vidare var kvaliteten på de granskade artiklarna genomgående låg (PEDro scale ≤ 5). Konklusion: Ytterligare forskning krävs för att fastställa vilken postoperativ behandling som ger bäst effekt. / Objective: Summarize and examine studies regarding postoperative treatment following rupture of the patellar ligament. Further the aim was to evaluate the effect of the postoperative treatment and the quality of the studies. Method: As design, a descriptive review was chosen, keywords: patellar ligament, patellar tendon, rupture, knee injuries, surgery. From a total of 1240 items, 13 relevant articles published 1999-2013 were selected after search in the databases PubMed, PEDro, COCHRANE, SCOPUS, CINAHL, SPORTDiscus and AMED. The articles were quality-graded according to PEDro scale. Results: Two postoperative treatments were described, early and delayed mobilization. There was no significant difference between them regarding the effect on muscle strength, range of motion and return to preinjury level of activity. The quality-graded articles had overall low quality (PEDro scale ≤ 5). Conclusion: Further researches are required to determine which postoperative treatment has the best effect.

Augmented Soft Tissue Mobilization, a massage therapy which uses a solid instrument rather than human fingers to treat musculoskeletal injuries, has been successful in treating tendinitis. Davidson et al. studied the functional and morphological affects of ASTM on collagenase induced Achilles tendinitis in Sprague-Dawley rats. Morphological observations showed a significant increase in the number and activation of fibroblasts in the ASTM treated Groups. The authors suggested that the physical force of ASTM may promote tendon healing via increased fibroblast recruitment. An important, but unexplained, question is how ASTM would affect the fibroblasts of native, noncollagenase injured, tendons. Studies have shown that mechanical forces can alter cellular functions. The purpose of this study was to examine the morphological changes in native Sprague-Dawley rat Achilles tendons after ASTM therapy using different application pressures.Three animal Groups were randomly established: A) control Group with no ASTM; B) light ASTM with 1 Newton of pressure; and C) heavy ASTM with 3 Newtons of pressure. Upon completion of the therapy, the Achilles tendons of each Group were examined with light and electron microscopy techniques to assess fibroblast number, tendon morphology, and the presence of type I and type III collagen. Fibroblast counts from each Group were compared using a two-way ANOVA, multiple regression, and curvilinear regression analysis. Morphological differences were shown between the three Groups, especially between the non force Group and the two force Groups. The ASTM Group treated with one Newton demonstrated the greatest mean fibroblast count (165.1+/-55.8&160.7+/-49.8). Electron microscopy revealed the presence of activated fibroblasts in the tendons of the two force Groups, ASTM Groups. Polarizing microscopy showed a dramatic increase in the amount of Type III collagen in the two force Groups compared to the non force Group.Ball State UniversityMuncie, IN 47306

Thesis (M.S.)--Mississippi State University. College of Veterinary Medicine. / Title from title screen. Includes bibliographical references.