CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Estabelecer em cadÃveres, dois portais, atravÃs da delimitaÃÃo de pontos anatÃmicos e linhas geomÃtricas, que permitam o acesso ao TÃnel do Tarso pela tÃcnica videoendoscÃpica e comparar a abordagem no sentido proximal para distal com a reversa. Fizeram parte do estudo 18 cadÃveres, com um total de 36 tornozelos. Partindo da tÃcnica endoscÃpica bi-portal inicialmente descrita, e modificada neste estudo atravÃs da padronizaÃÃo de pontos anatÃmicos e linhas geomÃtricas, o TÃnel do Tarso foi liberado nos tornozelos esquerdos com a inserÃÃo do instrumental no sentido proximal para distal e o inverso nos direitos. Nos tornozelos direitos, houve secÃÃo completa do retinÃculo flexor em 15 casos (83,3%) e parcial em 3 casos (16,67%). Nos esquerdos, a secÃÃo foi completa em 16 casos (88,89%) e parcial em 2 casos (11,11%). O tempo operatÃrio no lado direito foi em mÃdia 19,44 minutos e no esquerdo 18,33 minutos. Em nenhum caso foi observada lesÃo de estruturas neurovasculares. Com a tÃcnica proposta a secÃÃo total do retinÃculo dos flexores foi obtida em todos os casos apÃs a curva do aprendizado, sem lesÃo de estruturas anatÃmicas do tÃnel do Tarso, independente do sentido utilizado na via de acesso / Establish two portals in cadaver specimens, using anatomical delimitation points and geometrical lines, which allow the access to the tarsal tunnel by the video-endoscopic technique and the comparison between the proximal-distal direction approach with the reverse one. This trial has included 18 cadavers and 36 ankles were the total amount that was studied. Starting with the biportal endoscopic technique, initially described and modified in this trial through geometrical lines and anatomical points delimitation, the tarsal tunnel was released in left ankles with the insertion of instruments using proximal-distal direction and the opposite to the right ankles. There were, in the right ankles, complete section of flexor retinaculum in 15 cases (83,3%) and partial section in 3 cases (16,67%). In the left ankles there were complete section of flexor retinaculum in 16 (88,89%) and partial section in 2 cases (11,11%). The average operative time was 19,44 minutes for the right limb and 18,33 minutes for the left limb. No damage to neurovascular structures has been observed in any case. According to the suggested technique, the total section of flexors retinaculum was obtained in all the cases after learning curve period without lesion of anatomical structures in the tarsal tunnel, independent of whatever be the direction chosen in the access way

Plantar heel pain is commonly encountered by clinicians. Various conditions, such as plantar fasciopathy, myofascial syndrome and entrapment of the tibial, plantar and calcaneal nerves at the tarsal tunnel can cause plantar heel pain. This diversity in aetiology makes the diagnosis and treatment challenging. There are limited studies on pain mechanisms in patients with planter heel pain. There is no gold criterion standard for the diagnosis. Although various interventions have been reported, no specific treatment approach has yet been identified as being most effective. The first aim of this thesis was to critically appraise the literature on plantar heel pain of neural origin. Various databases were searched for peer-reviewed articles that predominantly focused on neurogenic plantar heel pain or that discussed relevant biomechanics of the tibial, plantar and calcaneal nerves. This review revealed inconsistency in the literature regarding the diagnosis and treatment of neurogenic plantar heel pain. There also was a lack of evidence for treatment approaches although the majority of patients with plantar heel pain are reported to improve with conservative treatment. The second aim of this thesis was to examine the biomechanical effects of clinical tests and combination of movements on various structures associated with plantar heel pain. This aim was achieved through cadaver studies (Study 1–3), in which strain in the plantar fascia and the nerves of the lower limb, and excursion of the nerves were measured during various movements and positions of the lower limb. Study 1 examined the Dorsiflexion-eversion test used to diagnose tarsal tunnel syndrome (TTS) and the Windlass test for plantar fasciopathy given the similarity between both tests. Both the Dorsiflexion-eversion and Windlass tests significantly increased strain in the structures that are commonly associated with plantar heel pain (the tibial and plantar nerves and plantar fascia). This suggests that the usefulness of the Dorsiflexion-eversion and Windlass tests in the differential diagnosis of plantar heel pain might be limited. Study 2 investigated the influence of different positions in adjacent joints on nerve biomechanics during ankle and toe movement. Increased strain in the tibial nerve at the ankle and plantar nerves associated with ankle and toe movement was significantly higher when the nervous system was pre-tensioned at a more proximal joint. Strain was even higher when the nerve bed was pre-tensioned at two joints. Study 3 examined a modified straight leg raising (SLR) test in which ankle dorsiflexion is performed before hip flexion. This test has been suggested to diagnose distal neuropathies such as TTS. During the modified SLR, the excursion and strain in the sciatic nerve associated with hip flexion were transmitted distally along the nerve from the hip to the foot. As a result, the strain in the nerves around the foot and ankle increased significantly during hip flexion. This movement did not affect plantar fascia strain. Consequently, the modified SLR may be a useful test to differentially diagnose plantar heel pain. This test warrants future research to evaluate its clinical use in patients with neurogenic plantar heel pain. The third aim of this thesis was to determine the reliability of high-resolution ultrasound for measuring the cross-sectional area of the tibial nerve at the tarsal tunnel and to compare the tibial nerve size between people with and without plantar heel pain. Study 4 investigated intra and intertester reliability in 10 participants without plantar heel pain by calculating intraclass correlation coefficients, measurement error and smallest detectable difference (SDD). Intra and intertester reliability were excellent, with very small measurement error and SDD. Tibial nerve enlargement in an individual patient by as little as 1.8 mm2 can be detected reliably with high-resolution ultrasound. The use of average value of three scans is recommended to compare between the involved and uninvolved side. Differences in the nerve size between 26 patients with plantar heel pain and 20 control participants were also analysed. There was no significant difference in tibial nerve size between both groups. Future research is needed to investigate the tibial nerve size in patients with proven TTS using ultrasonography. The fourth aim of this thesis was to investigate the characteristics of plantar heel pain through Study 5 for the same group of patients and control participants as in Study 4. Several self-report measures on pain and quality of life were used. Clinical tests and quantitative sensory tests (QST) were performed at local and remote sites on the involved and uninvolved side in the patients and on one side in the control participants. In the patients, mechanical hyperalgesia was the main finding as demonstrated by changes in palpation and pressure pain threshold. Other findings were changes in current thresholds, vibration threshold and thermal perception thresholds. These results suggest the existence of sensory changes that likely indicates change in peripheral and central pain processing. It is recommended to utilise a multidimensional pain assessment for patients with plantar heel pain. The findings in this thesis are important for the diagnosis and treatment of plantar heel pain. For future research, the results suggest to use fresh cadavers when investigating biomechanics of the clinical tests and nerve gliding exercises that are used for patients with plantar heel pain. It is also suggested to evaluate the cross-sectional area of the tibial nerve at the tarsal tunnel, the QSTs and all other diagnostic measurements in this thesis in patients with neurogenic plantar heel pain or patients with TTS.

INTRODUÇÃO: Estudos experimentais e clínicos, realizados por diversos autores, demonstraram a susceptibilidade à compressão nervosa periférica na vigência da diabetes mellitus e modificações na evolução natural da doença após descompressões nervosas cirúrgicas dos sítios propícios a constrição neural. Em membros inferiores, a síndrome do túnel do tarso sobreposta às neuropatias vigentes ainda gera conflitos na literatura. A anatomia do nervo tibial e seus ramos ao nível do terço distal da perna e túnel do tarso apresentam variações importantes que não são contempladas nos livros texto e atlas de anatomia. OBJETIVO: Determinar, através de dissecção em cadáveres frescos, a anatomia topográfica do nervo tibial e seus ramos ao nível do tornozelo, em relação ao túnel do tarso. MATERIAL E MÉTODOS: O estudo foi realizado através da dissecção anatômica bilateral de 26 cadáveres frescos. Foi fixada, entre o cento do maléolo medial e o centro do calcâneo, uma linha de referência (eixo maleolar-calcaneal). Com base nesse eixo as localizações da bifurcação do nervo tibial e dos ramos calcâneos mediais e inferiores foram aferidas em milímetros. Para as bifurcações foi estabelecida uma classificação por tipos de I a V, baseada no posicionamento em relação ao túnel do tarso (definido como dois centímetros proximais e distais ao eixo). Para os ramos calcâneos, a quantidade e seus respectivos nervos de origens também foram analisados. Os resultados foram transformados em taxas (porcentagem) e comparados aos achados de outros estudos. RESULTADOS: Vinte e seis cadáveres (50 pernas) foram pesquisados. A bifurcação do nervo tibial ocorreu sob o túnel em 88% dos casos e proximalmente em 12%. Tivemos o tipo I em 52%, tipo II em 14%, tipo III em 22%, tipo IV em 12% e o tipo V não foi visualizado. Quanto ao ramo calcâneo medial encontramos: um (58%), dois (34%) e três (8%), com a origem mais comum ocorrendo do nervo tibial (90%). De um total de 75 ramos calcâneos mediais dissecados, 40 tiveram sua origem fora do túnel proximalmente (53,3%) e os demais dentro. Com referência ao ramo calcâneo inferior, constatou-se a presença de um único ramo por perna, com 92% emergindo sob o retináculo flexor, 4% proximalmente e 4% distalmente a ele. A origem mais comum foi do nervo plantar lateral (70%), seguida do nervo tibial (18%). CONCLUSÕES: 1- A bifurcação do nervo tibial nos ramos plantares medial e lateral ocorreu sob o retináculo flexor em 88% das pernas, localizando-se, em 70% das vezes, em uma área compreendida entre 10 mm proximais e distais ao EMC. 2- O ramo calcâneo medial apresentou grande variação tanto na sua origem e número de ramos quanto na sua localização em relação ao túnel do tarso. A apresentação de um ramo com origem do nervo tibial, no túnel ou proximalmente a ele, foi a mais observada (58%). 3- O ramo calcâneo inferior esteve sempre presente e com certo grau de variação quanto a sua origem. A apresentação de ramo único oriundo do nervo plantar lateral foi a mais constante (70%) / INTRODUCTION: Experimental and clinical studies developed by several authors displayed the susceptibility to peripheral nerve compression in the presence of diabetes mellitus and changes in the natural evolution of the disease after surgical nerve decompressions of the propitious sites of neural constriction. In lower members, the tarsal tunnel syndrome overlapped on neuropathies still generates conflicts in the available literature. The tibial nerve and its branches anatomy at the distal leg level present significant variations that are not contemplated in textbooks and anatomy atlas. OBJECTIVE: Determine through dissection in fresh cadavers, the topographic anatomy of the tibial nerve and its branches at the ankle, in relation to the tarsal tunnel. MATERIAL AND METHODS: The study was accomplished through bilateral anatomical dissection of 26 fresh cadavers. A reference line was fixed between the center of medial malleolus and the center of calcaneus (malleolarcalcaneal axis - MCA). Based on this axis, the locations of the tibial nerve bifurcation and its medial and lower calcaneal branches were measured in millimeters. For the bifurcations, it was established a classification by types I to V, based in positioning related to the tarsal tunnel (defined as two centimeters proximal and distal to the axis). For the calcaneal branches, the amount and their respective nerves of origin were also analyzed. The results were transformed in rates (percentages) and compared with findings of other studies. RESULTS: Twenty six cadavers (50 legs) were investigated. The tibial nerve bifurcation occurred under the tunnel in 88% of the cases and proximally in 12%. The study had the type I in 52%, type II in 14%, type III in 22%, type IV in 12% and type V was not visualized. As for the medial calcaneal branch it was found: one (58%), two (34%) and three (8%), with the most common source occurring in the tibial nerve (90%). A total of 75 medial calcaneal branches dissected, 40 had their origin outside the tunnel proximally (53.3%) and others had within. With reference to the lower calcaneal branch, it was detected the presence of a single branch per leg, with 92% emerging under the flexor retinaculum, 4% proximally and 4% distally to it. The most common origin was the plantar lateral nerve (70%) followed by the tibial nerve (18%). CONCLUSIONS: 1- The bifurcation of the tibial nerve in the medial and lateral plantar branches occurred under the flexor retinaculum in 88% of the legs, locating, 70% of the time, in an area between 10 mm proximal and distal to the MCA. 2- The medial calcaneal branch presented wide variation as much in its origin as in its location in relation to the tarsal tunnel. The presentation of one branch originating from the tibial nerve in the tunnel or proximally to it was the most observed (58%). 3- The lower calcaneal branch was always present and with a certain degree of variation related to its origin. The presentation of a single branch from the lateral plantar nerve was the most constant (70%)

INTRODUÇÃO: Estudos experimentais e clínicos, realizados por diversos autores, demonstraram a susceptibilidade à compressão nervosa periférica na vigência da diabetes mellitus e modificações na evolução natural da doença após descompressões nervosas cirúrgicas dos sítios propícios a constrição neural. Em membros inferiores, a síndrome do túnel do tarso sobreposta às neuropatias vigentes ainda gera conflitos na literatura. A anatomia do nervo tibial e seus ramos ao nível do terço distal da perna e túnel do tarso apresentam variações importantes que não são contempladas nos livros texto e atlas de anatomia. OBJETIVO: Determinar, através de dissecção em cadáveres frescos, a anatomia topográfica do nervo tibial e seus ramos ao nível do tornozelo, em relação ao túnel do tarso. MATERIAL E MÉTODOS: O estudo foi realizado através da dissecção anatômica bilateral de 26 cadáveres frescos. Foi fixada, entre o cento do maléolo medial e o centro do calcâneo, uma linha de referência (eixo maleolar-calcaneal). Com base nesse eixo as localizações da bifurcação do nervo tibial e dos ramos calcâneos mediais e inferiores foram aferidas em milímetros. Para as bifurcações foi estabelecida uma classificação por tipos de I a V, baseada no posicionamento em relação ao túnel do tarso (definido como dois centímetros proximais e distais ao eixo). Para os ramos calcâneos, a quantidade e seus respectivos nervos de origens também foram analisados. Os resultados foram transformados em taxas (porcentagem) e comparados aos achados de outros estudos. RESULTADOS: Vinte e seis cadáveres (50 pernas) foram pesquisados. A bifurcação do nervo tibial ocorreu sob o túnel em 88% dos casos e proximalmente em 12%. Tivemos o tipo I em 52%, tipo II em 14%, tipo III em 22%, tipo IV em 12% e o tipo V não foi visualizado. Quanto ao ramo calcâneo medial encontramos: um (58%), dois (34%) e três (8%), com a origem mais comum ocorrendo do nervo tibial (90%). De um total de 75 ramos calcâneos mediais dissecados, 40 tiveram sua origem fora do túnel proximalmente (53,3%) e os demais dentro. Com referência ao ramo calcâneo inferior, constatou-se a presença de um único ramo por perna, com 92% emergindo sob o retináculo flexor, 4% proximalmente e 4% distalmente a ele. A origem mais comum foi do nervo plantar lateral (70%), seguida do nervo tibial (18%). CONCLUSÕES: 1- A bifurcação do nervo tibial nos ramos plantares medial e lateral ocorreu sob o retináculo flexor em 88% das pernas, localizando-se, em 70% das vezes, em uma área compreendida entre 10 mm proximais e distais ao EMC. 2- O ramo calcâneo medial apresentou grande variação tanto na sua origem e número de ramos quanto na sua localização em relação ao túnel do tarso. A apresentação de um ramo com origem do nervo tibial, no túnel ou proximalmente a ele, foi a mais observada (58%). 3- O ramo calcâneo inferior esteve sempre presente e com certo grau de variação quanto a sua origem. A apresentação de ramo único oriundo do nervo plantar lateral foi a mais constante (70%) / INTRODUCTION: Experimental and clinical studies developed by several authors displayed the susceptibility to peripheral nerve compression in the presence of diabetes mellitus and changes in the natural evolution of the disease after surgical nerve decompressions of the propitious sites of neural constriction. In lower members, the tarsal tunnel syndrome overlapped on neuropathies still generates conflicts in the available literature. The tibial nerve and its branches anatomy at the distal leg level present significant variations that are not contemplated in textbooks and anatomy atlas. OBJECTIVE: Determine through dissection in fresh cadavers, the topographic anatomy of the tibial nerve and its branches at the ankle, in relation to the tarsal tunnel. MATERIAL AND METHODS: The study was accomplished through bilateral anatomical dissection of 26 fresh cadavers. A reference line was fixed between the center of medial malleolus and the center of calcaneus (malleolarcalcaneal axis - MCA). Based on this axis, the locations of the tibial nerve bifurcation and its medial and lower calcaneal branches were measured in millimeters. For the bifurcations, it was established a classification by types I to V, based in positioning related to the tarsal tunnel (defined as two centimeters proximal and distal to the axis). For the calcaneal branches, the amount and their respective nerves of origin were also analyzed. The results were transformed in rates (percentages) and compared with findings of other studies. RESULTS: Twenty six cadavers (50 legs) were investigated. The tibial nerve bifurcation occurred under the tunnel in 88% of the cases and proximally in 12%. The study had the type I in 52%, type II in 14%, type III in 22%, type IV in 12% and type V was not visualized. As for the medial calcaneal branch it was found: one (58%), two (34%) and three (8%), with the most common source occurring in the tibial nerve (90%). A total of 75 medial calcaneal branches dissected, 40 had their origin outside the tunnel proximally (53.3%) and others had within. With reference to the lower calcaneal branch, it was detected the presence of a single branch per leg, with 92% emerging under the flexor retinaculum, 4% proximally and 4% distally to it. The most common origin was the plantar lateral nerve (70%) followed by the tibial nerve (18%). CONCLUSIONS: 1- The bifurcation of the tibial nerve in the medial and lateral plantar branches occurred under the flexor retinaculum in 88% of the legs, locating, 70% of the time, in an area between 10 mm proximal and distal to the MCA. 2- The medial calcaneal branch presented wide variation as much in its origin as in its location in relation to the tarsal tunnel. The presentation of one branch originating from the tibial nerve in the tunnel or proximally to it was the most observed (58%). 3- The lower calcaneal branch was always present and with a certain degree of variation related to its origin. The presentation of a single branch from the lateral plantar nerve was the most constant (70%)