Bakgrund: En akut akillesseneruptur (ATR) resulterar i begränsning av funktion som kan kvarstå under lång tid. I litteraturen finns ett flertal reliabla och valida utvärderingsinstrument som används vid funktionsbedömningar efter ATR. Då osäkerhet angående lämpligt val av tester inför återgång i aktivitet/idrott föreligger finns ett behov av tydliga riktlinjer i fråga om kliniskt relevanta utvärderingsinstrument. Syfte: Syftet med studien var att identifiera kliniskt relevanta fysioterapeutiska utvärderingsinstrument för bedömning av funktion hos personer med akillesseneruptur samt kartlägga dessa utifrån ett validitets och reliabilitetperspektiv. Metod: En kartläggande litteraturstudie. Litteratursökningen genomfördes i databaserna PubMed, Cinahl och PEDro mellan 2023-02-07 – 2023-02-15 utifrån inklusionskriterierna: vuxna individer med akut ATR, artiklar publicerade 2013-2023, observations- och randomiserade kontrollerade studier. Av identifierade utvärderingsinstrument valdes 15 ut, baserat på kriterierna: frekvens, klinisk användbarhet samt kategorisering enligt ramverket International Classification of Functioning, Disability and Health (ICF). Valda utvärderingsinstrument kategoriserades enligt ICF samt granskades avseende reliabilitet och validitet om denna data fanns tillgänglig. Resultat: Totalt inkluderades 15 olika utvärderingsinstrument, såväl objektiva som subjektiva, för granskning utifrån reliabilitet och validitet. Fem av dessa visade både god reliabilitet och validitet samt klinisk användbarhet. Inga diagnosspecifika utvärderingsinstrument inom ICF-kategorierna personlighetsfaktorer och omgivningsfaktorer identifierades. Slutsats: Achilles Tendon Resting Angle (ATRA), Achilles Tendon Total Rupture Score (ATRS), Foot and Ankle Outcomes Score (FAOS), Heel-Rise Endurence och Heel-Rise Height är fem tillförlitliga utvärderingsinstrumnet att använda i klinik. Inför återgång till aktivitet/idrott är det nödvändigt att komplettera med idrottsspecifika utvärderingsinstrument samt instrument som utvärderar psykologiska faktorer. / Background: An acute achilles tendon rupture (ATR) results in limitations of function that remains for a long time. There are several reliabel and valid outcome measures used in functional evaluation after ATR presented in the litterature. Due to uncertainties regarding which appropriate outcome measures to use for return to activities/sports there is a need for clinical guidelines. Purpose: The purpose was to identify physiotherapeutic outcome measures for the evaluation of function in people with achilles tendon ruptures and to chart these from a perspecive of reliability and validity. Method: A scoping review. A litterature search were performed in the databases PubMed, Cinahl and PEDro between 2023-02-07 – 2023-02-15 based on the inclusion criteria: adults with acute ATR, articles published between 2013-2023, clinical trials and randomized controlled trials. From identified outcome measures 15 were selected based on the criteria frequency, clinical usability and categorized by the theoretical framework International Classification of Functioning, Disability and Health (ICF). Selected outcome measures were categorized according to ICF and reviewed for republicity of results, if this data was available. Results: 15 outcome measures, both objective and subjective, were included for evaluation regarding reliability and validity. Five of these proved good reliability, validity and clinical usability. In the ICF categories, personal factors and environmental factors, no diagnose specific outcome measures were identified. Conclusion: Achilles Tendon Resting Angle (ATRA), Achilles Tendon Total Rupture Score (ATRS), Foot and Ankle Outcomes Score (FAOS), Heel-Rise Endurence och Heel-Rise Height are five reliable outcome measures to use in clinical practice. Before return to activities/sports it is necessary to add sportspecific outcome measures and evaluation of psychological factors.

In der Präadoleszenz verbessert sportliches Training die Muskelkraftkapazität, die Belege für Auswirkungen auf Muskel- und Sehnenplastizität sind jedoch begrenzt. Jedoch könnte es, ähnlich wie bei jugendlichen Sportler:innen, bei präadoleszenten Athlet:innen zu Dysbalancen zwischen Muskelkraft und Sehnensteifigkeit kommen, insbesondere bei häufigen plyometrischen Belastungen. Dadurch wird die Sehne stärker mechanisch beansprucht, was zu einem erhöhten Verletzungsrisiko der Sehne führen kann. Aufgrund des Forschungsmangels über die Auswirkungen sportlichen Trainings auf die Muskel- und Sehnenplastizität in der Präadoleszenz untersucht die vorliegende Arbeit die Entwicklung der morphologischen und mechanischen Eigenschaften der Plantarflexoren und der Achillessehne bei präadoleszenten Athlet:innen mittels Ultraschall- und Dynamometrie. Es wurden zwei Vergleichsstudien zwischen Turner:innen mit mehrjähriger Trainingserfahrung und untrainierten Personen ähnlichen Alters durchgeführt. Die Studien zeigten eine höhere Muskelkraft der Plantarflexoren bei den Athlet:innen, jedoch keine Anpassungen der Achillessehnensteifigkeit, was zu einem höheren Anteil von Athlet:innen mit stark erhöhter Sehnendehnung führte. Zudem gab es keine Hinweise auf eine trainingsbedingte Muskelhypertrophie der Plantarflexoren. Die Auswirkungen von Training und Reifung auf die Muskel-Sehnen-Einheit wurden zusätzlich über ein Jahr untersucht. Die Muskelkraft der Athlet:innen entwickelte sich im Vergleich zu Nichtathlet:innen ähnlich, war jedoch durch größere Schwankungen und eine unausgewogene Adaptation zwischen Muskelkraft und Sehnensteifigkeit gekennzeichnet. Dies führte zu einer höheren Häufigkeit von Sportler:innen mit erhöhter Sehnendehnung und größeren Schwankungen der Sehnendehnung über die Zeit. Die Ergebnisse deuten auf eine erhöhte mechanische Beanspruchung der Sehne bei präadoleszenten Athlet:innen hin, was Auswirkungen auf das Risiko von Überlastungsbeschwerden der Sehne haben könnte. / In preadolescence, physical exercise and athletic training improve muscle strength capacity, yet the evidence on the effects of long-term athletic training on muscle-tendon plasticity is limited. Similar to adolescent athletes, preadolescents might develop imbalances between muscle strength and tendon stiffness, particularly with high-frequency plyometric loading. This imbalance exposes the tendon to an increased mechanical demand, potentially leading to an increased risk of tendon injury. Despite limited evidence on preadolescence research about the effects of athletic training on muscle-tendon plasticity, the thesis investigates the development of morphological and mechanical properties of the plantar flexors and Achilles tendon in preadolescent athletes via ultrasonography and dynamometry procedures. Two comparison studies were initially performed between artistic gymnastic athletes, with extensive training history, against untrained peers of similar age. The studies demonstrated higher plantar flexor muscle strength in the athletes, yet the gymnastic-specific training did not cause adaptations of Achilles tendon stiffness, resulting in a higher percentage of athletes with high-level tendon strain. Moreover, there was no evidence of training-induced muscle hypertrophy in the plantar flexors. The effects of athletic training and maturation on the triceps surae muscle-tendon unit were investigated over one year during preadolescence. The development of muscle strength in athletes, even though it was similar compared to non-athletes, was characterised by significantly greater fluctuations and a non-uniform adaptation between muscle strength and tendon stiffness. These two facts together resulted in a higher frequency of athletes with a high level of tendon strain and greater strain fluctuations over time. The findings indicate an increased mechanical demand for the tendon in preadolescent athletes that could have implications for the risk of tendon overuse injury.

Abstract Achilles tendon rupture (ATR) conservative treatment result usually good clinical outcome, but despite the treatment method calf muscle strength deficit persist. Recent evidence suggests that surgery might surpass conservative treatment in restoring strength after ATR, but structural explanations for surgery-related improved strength remain uncertain. The purposes of this thesis were to compare calf muscle isokinetic strength recovery, calf muscle volume, fatty degeneration and AT elongation after conservative treatment or after open surgical repair of ATR. An additional aim was to assess the role of fascial augmentation in terms of calf muscle isokinetic strength recovery, AT elongation, calf muscle volume atrophy and fatty degeneration, and their relationship with calf muscle isokinetic strength in long-term follow-up after ATR surgery. Surgery resulted in 10% to 18% greater plantar flexion strength (P = 0.037) compared to conservative treatment. The mean differences between affected and healthy soleus muscle volumes were -18% after surgery and -25% after conservative treatment (P = 0.042). At 18 months, AT were, on average 19 mm longer in patients treated conservatively compared to surgery (P < 0.001). At 18 months, patients with greater (2–3) fatty degeneration had lower soleus muscle volumes and plantar flexion strength in the healthy leg. In long term, augmentation did not affect any of the strength variables, but the injured side showed 12% to 18% strength deficit compared with the healthy side (P < 0.001). The AT was, on average, 12 mm longer in the affected leg than in the healthy leg (P < 0.001). The mean soleus muscle volume was 13% lower in the affected leg than in the healthy leg (P < 0.001). The mean volumes of the medial- and lateral gastrocnemius muscles were 12% and 11% lower in the affected leg than in the healthy leg, respectively (P < 0.001). AT elongation correlated substantially with plantar strength deficit (ρ = 0.51, P < 0.001) and with both gastrocnemius (ρ = 0.46, P = 0.001) and soleus muscle atrophy (ρ = 0.42, P = 0.002). Calf muscle fatty degeneration was more common in the affected leg compared healthy leg (P ≤ 0.018). In conclusion, surgery of ATR restored calf muscle isokinetic strength earlier and more completely than conservative treatment. Conservative treatment resulted in greater soleus muscle atrophy and AT elongation compared surgery, which may partly explain the surgery related better strength results. Augmentation provided no long-term benefits compared with simple suturation, and a 12 to 18% plantar flexion strength deficit compared to the healthy side persisted. AT elongation may explain the smaller calf muscle volumes, greater fatty degeneration, and plantar flexion strength deficit observed in long-term follow-up after surgical repair of ATR. / Tiivistelmä Akillesjännerepeämän (ATR) konservatiivisella ja leikkaushoidolla hoidolla saavutetaan hyvät kliiniset tulokset. Viimeisimmät tutkimukset kuitenkin viittaavat leikkaushoidolla saavutettavan paremmat voimat kuin konservatiivisella hoidolla, mutta rakenteelliset selitykset leikkaushoidon paremmalle pohjelihaksen voimille ovat epäselviä. Työn tarkoituksena oli verrata pohjelihaksen isokineettisten voimien palautumista, pohjelihastilavuuksia, rasvadegeneraatiota ja akillesjänteen (AT) pidentymistä ATR:n konservatiivisen- ja leikkaushoidon jälkeen. Tarkoituksena oli arvioida lihaskalvovahvikkeen merkitystä pohjelihaksen isokineettisten voimien palautumisessa pitkäaikaisseurannassa. Lisäksi tutkimme AT pidentymisen, pohjelihastilavuuksien ja rasvadegeneraation suhdetta pohjelihaksen isokineettisiin voimiin ATR:n leikkaushoidon jälkeen 14 v seurannassa. Leikkaushoidolla saavutettiin 10–18 % paremmat pohjelihaksen voimat verrattuna konservatiiviseen hoitoon. Leikkaushoidon jälkeen soleuslihasten tilavuuksien puoliero terveen jalan hyväksi oli 18 % ja konservatiivisen hoidon jälkeen 25 %. 18 kk kohdalla konservatiivisesti hoidettujen AT oli 19 mm pidempi verrattuna leikkauksella hoidettuihin. 18 kk kohdalla potilaat, joilla vamma jalan soleuslihaksen rasva-degeneraatio oli korkea (2–3), kärsivät suuremmasta soleuslihaksen atrofiasta ja pohjelihaksen voima puolierosta. Voimat eivät muuttuneet 12 kk ja 14 v kontrollien välillä. Lihaskalvovahvikkeella ei ollut merkitystä voimien palautumisessa pelkkään suoraan ompeluun verrattuna, mutta vammapuoli jäi 10–18 % heikommaksi verrattuna terveeseen jalkaan. Vammajalan akillesjänne oli 12 mm pidempi terveeseen jalkaan verrattuna. Vammajalan kolmipäisen pohjelihaksen tilavuus oli 11–13 % pienempi verrattuna terveeseen jalkaan. Akillesjänteen pituus korreloi pohjelihaksen voimapuolieron sekä pohjelihasatrofian kanssa. Akillesjännerepeämän leikkaushoidolla pohjelihaksen isokineettiset voimat palautuvat nopeammin ja täydellisemmin kuin konservatiivisella hoidolla. Leikkaushoitoon verrattuna konservatiivinen hoito johtaa suurempaan soleuslihaksen atrofiaan ja akillesjänteen pidentymään, mikä selittää osittain leikkaushoidon paremmat voimatulokset. 14 v seurannassa lihaskalvovahvikkeesta ei ole etua akillesjännerepeämän leikkaushoidossa. Akillesjännerepeämän leikkaushoidosta huolimatta potilaalle jää terveeseen jalkaan verrattuna 10–18 % pohjelihasten voimapuoliero. Akillesjänteen pidentyminen mahdollisesti selittää pohjelihasten atrofian, rasvadegeneraation ja pysyvän pohjelihasten voimapuolieron akillesjännerepeämän leikkaushoidon jälkeen 14 v seurannassa.

Indiana University-Purdue University Indianapolis (IUPUI) / Tendinopathy is a common degenerative pathology that is characterized by activity related pain, focal tendon tenderness, intratendinous imaging changes, and typically results in changes in the histological, mechanical, and molecular properties of the tendon. Tendinopathy is difficult to study in humans, which has contributed to limited knowledge of the pathology, and thus a lack of appropriate treatment options. However, most believe that the pathology is degenerative as a result of a combination of both extrinsic and intrinsic factors. In order to gain understanding of this pathology, animal models are required. Because each tendon is naturally exposed to different conditions, a universal model is not feasible; therefore, an appropriate animal model must be established for each tendon susceptible to degenerative changes. While acceptable models have been developed for several tendons, a reliable model for the Achilles tendon remains elusive. The purpose of this dissertation was to develop an animal model of Achilles tendinopathy by investigating the individual and combined effects of an intrinsic and extrinsic factor on the rodent Achilles tendon. Rats selectively bred for high capacity running and Sprague Dawley rats underwent uphill treadmill running (an extrinsic factor) to mechanically overload the Achilles tendon or served as cage controls. Collagenase (intrinsic factor) was injected into one Achilles tendon in each animal to intrinsically break down the tendon. There were no interactions between uphill running and collagenase injection, indicating that the influence of the two factors was independent. Uphill treadmill running alone failed to produce any pathological changes in the histological or mechanical characteristics of the Achilles tendon, but did modify molecular activity. Intratendinous collagenase injection had negative effects on the histological, mechanical, and molecular properties of the tendon. The results of this dissertation demonstrated that the combined introduction of uphill treadmill running and collagenase injection did not lead to degenerative changes consistent with human Achilles tendinopathy. Intratendiouns collagenase injection negatively influenced the tendon; however, these changes were generally transient and not influenced by mechanical overload. Future studies should consider combinations of other intrinsic and extrinsic factors in an effort to develop an animal model that replicates human Achilles tendinopathy.