Um estudo terapêutico comparativo prospectivo é realizado para avaliar o acesso posterior minimamente invasivo em artroplastia total do quadril comparado com o acesso lateral direto tradicional. O estudo inclui 76 pacientes submetidos à artroplastia total do quadril primárias não cimentadas por diagnóstico de osteoartrose primária e secundária. Não são incluídos, pacientes com qualquer tipo de coagulopatia, em uso de anticoagulantes ou antiagregante plaquetário, pacientes hipertensos sem controle medicamentoso, pacientes submetidos à qualquer cirurgia prévia do quadril, e pacientes com seqüela de displasia do desenvolvimento do quadril que tenham a cabeça femoral ectópica. O objetivo principal deste estudo é avaliar a perda volêmica que ocorre nestes pacientes. Há diferença de média de idade (p=0,017) no acesso minimamente invasivo (50,1 anos) em relação ao grupo controle (56,8 anos), porém não observamos diferenças entre os grupos quanto ao índice de massa corpórea, lado operado e diagnóstico inicial. Observa-se um sangramento menor (p<0,001) no período intra-operatório (745,6 ml contra 1282,8 ml), assim como, menor sangramento total (p<0,001) no acesso minimamente invasivo posterior (1083,5 ml contra 1682,3 ml). Relatamos diferença entre os grupos quanto à necessidade de transfusão alogênica, favorável aos pacientes do grupo minimamente invasivo (p=0,02), com 8,8% dos pacientes sendo transfundidos em relação a 28,6% dos pacientes do grupo controle. Nossa estimativa de sangramento no acesso minimamente invasivo posterior é significativamente maior que a literatura, porém a quantidade de unidades de concentrados de hemáceas transfundidas,assim como, a proporção de pacientes transfundidos são menores em relação aos outros autores. Concluímos que os pacientes submetidos ao acesso minimamente invasivo posterior apresentam menor sangramento, melhor resultado clínico precoce e posicionamento adequado dos componentes da prótese. / A therapeutic, comparative, prospective study was carried out to evaluate the minimally invasive posterior approach to total hip arthroplasty in relation to the traditional direct lateral approach. The study included 76 cases of primary total hip arthroplasty due to a diagnosis of primary or secondary osteoarthrosis. Patients were excluded from the study if they presented any type of coagulopathy and were using anticoagulants or platelet antiagregants; hypertension without medicinal control; any previous hip surgery; and sequelae of hip developmental dysplasia that might have led to an ectopic femoral head. The objective of our study was to evaluate the blood loss among patients for whom the minimally invasive posterior access is used. Regarding our patients\' ages, we observed a significant difference between the two groups: the mean age of the mini-incision group (50,1 years) was lower than the mean of the control group (56,8 years), p= 0.01. Lower total estimated bleeding was found in the mini-incision group (means of 1083,5 ml versus 1682,3 ml; p < 0.001) and lower intraoperative bleeding (means of 745,6 ml versus 1282,8 ml; p <0.001). There was difference in the need of allogenic transfusion between the two groups (8,8% versus 28,6%,p = 0.13). Our volumes of bleeding from the minimally invasive posterior approach were significantly higher than in the literature, but the mean quantity of transfused red cells and the proportion of transfused patients were both significantly lower than in the literature. Our final impression of the minimally invasive approach is positive with regard to lower blood loss, better clinical results after six months and a satisfactory alignment of the acetabular and femoral components.

A vibroacustografia (VA) é uma técnica de imagem de alta resolução lateral (<0,7 mm), livre de speckles, não invasiva e que utiliza radiação não-ionizante, baseada no fenômeno de combinação não-linear de ondas de ultrassom (MHz) que gera uma região focal estreita de baixa frequência (kHz). Neste trabalho, propõe-se uma avaliação tridimensional baseada em imagens de VA da área descoberta de implantes, após o procedimento cirúrgico de artroplastia total de quadril (ATQ). A ATQ é uma técnica terapêutica de substituição de articulações do quadril por implantes, em pacientes com osteoartrose avançada. Atualmente, o acompanhamento pós-operatório é auxiliado pela análise de radiografia plana por raios-X. Contudo, esta técnica apresenta limitações na avaliação da estabilidade dos implantes, tais como: avaliação imprecisa da área, uma vez que, a radiografia plana trata o problema tridimensional como bidimensional; impossibilidade de visualização de algumas regiões do implante, devido ao sobreposicionamento das regiões numa imagem planar; restrição do uso de radiação ionizante na região da pelve em pacientes jovens. Devido à alta atenuação da onda de ultrassom incidindo sobre objetos densos, a VA pode ser ajustada para adquirir imagens relativas, principalmente, à superfície destes. Uma correção da topologia baseada na geometria do implante é apresentada, a fim de se avaliar com precisão a área superficial na representação tridimensional da imagem de VA. A correção da topologia baseada em aquisições em modo-B também é apresentada, sendo útil na avaliação da forma de ossos ou nos casos em que a forma do objeto estudado é desconhecida. Além disso, é apresentado um estudo numérico da utilização de transdutores matriciais reconfiguráveis (RCA, do inglês reconfigurable array) para a formação de feixe em VA. Um estudo paramétrico da seleção de abertura, número de canais, número de elementos, distância focal e parâmetros de varredura eletrônica do feixe é apresentado para demonstrar a viabilidade e avaliar o desempenho da imagem de VA utilizando o RCA. A função de espalhamento de ponto do sistema foi calculada com base em métodos de espectro angular usando a aproximação de Fresnel para fontes retangulares. Foram discutidas as vantagens de transdutores bidimensionais e RCA, e aspectos relacionados à importância clínica da implementação do RCA na VA, tais como resolução espacial, taxa de aquisição da imagem e implementação do RCA em máquinas comerciais. Conclui-se que: a aquisição de imagens por VA foi menos sensível ao ângulo de incidência das ondas de ultrassom do que por modo-B e apresentou alta resolução e alto contraste entre o osso e o implante, o que permitiu uma avaliação precisa da área exposta do implante; os transdutores RCA podem aprimorar a aquisição de imagens por VA, devido à sua resolução espacial similar à de transdutores confocais e à possibilidade de deflexão eletrônica do feixe (em inglês steering) nos planos de elevação e azimutal. / Vibro-acoustography (VA) is a high lateral resolution (<0.7 mm), speckle-free, non- ionizing and non-invasive image based on the nonlinear combination phenomenon of ultrasound waves (MHz) that generates a narrow focus region of low frequency (kHz). In this work, we propose a VA-based tridimensional evaluation of the exposed area of implants, after total hip arthroplasty (THA). THA is a therapeutic surgery procedure in which the hip joints are replaced by metal prostheses in patients with advanced osteoarthritis. Currently, the postoperative assessment of THA is performed by analyzing planar X-ray radiographies. However, this technique presents limitations in the implant stability evaluation such as: inaccurate evaluation of the area, since the planar radiography reduces the tridimensional problem into a two-dimensional one; problems in the visualization of some regions of the implants due to the superimposition of the regions; limitations of using ionizing radiation in the pelvis region of young patients. Due to the high attenuation of the ultrasound wave into objects of high density, the VA image can be set to mainly acquire the surface information. Topological correction based on the geometry of the implant is presented in order to accurately evaluate the surface area in tridimensional representation of the VA image. The topological correction based on B-mode slices is also presented and is useful in the evaluation of bone shape or in cases which the shape of the object is unknown. Furthermore, it is presented a numerical study of the use of reconfigurable arrays (RCA) for VA beam formation. A parametric study of the aperture selection, number of channels, number of elements, focal distance and steering parameters is presented in order to show the feasibility and evaluate the performance of VA imaging based on RCA. The point-spread function of the system is calculated based on angular spectrum methods using the Fresnel approximation for rectangular sources. Advantages of two-dimensional and RCA arrays and aspects related to clinical importance of the RCA implementation in VA such as spatial resolution, image frame-rate, and commercial machine implementation are discussed. It is concluded that: the VA image is less sensitive to the wave incident angle than B-mode; the VA image presents high-resolution and high-contrast between bone and implant, which allowed an accurate evaluation of the uncovered area; RCA transducers improve the VA acquisition by producing spatial resolution similar to confocal transducers, and due to the possibility of steering in elevation and azimuthal planes.

Este estudo compara dois protocolos de reabilitação fisioterapêutica - um com três meses de duração (protocolo padrão IOT) e outro com dois meses (protocolo avançado) - para evidenciar a real necessidade de um tempo prolongado de reabilitação em 31 pacientes submetidas a artroplastia total do joelho. O estudo é prospectivo e randomizado e a faixa etária avaliada está entre 60 e 76 anos. As pacientes são avaliadas no pré-operatório e após o tratamento com avaliação clínica (escala de dor, Knee Society Score, SF-36 e goniometria) e avaliação de força (avaliação isocinética) para comparação dos protocolos. A análise estatística dos valores da escala de dor, do Knee Society Score, da amplitude de movimento, do pico de torque muscular e da avaliação da qualidade de vida (SF-36) demonstra que todas as pacientes obtêm melhora quando comparamos o pré e pós-operatório, independente do grupo. Conclui-se que o protocolo de reabilitação fisioterapêutica com dois meses de duração para o pós-operatório de artroplastia total do joelho mostra ser eficaz, alcançando os mesmos objetivos e resultados que o protocolo com três meses de duração / The present study compares two physiotherapeutic rehabilitation protocols - one lasting three months (standard IOT protocol), the other lasting two months (advanced protocol) - to assert the actual need of a prolonged rehabilitation period in 31 cases of patients who went through total knee arthroplasty. The study is prospective and randomized; the age group of evaluated patients is between 60 and 76 years-old. In order to compare the two protocols, patients are evaluated before surgery and after treatment, by means of clinical evaluation (pain scale, Knee Society Score, SF-36 and goniometry) and isokinetic strength test. Statistical analyses of results from pain scale, Knee Society Score, movement amplitude, muscular torque peak and quality of life show improvement for all patients between pre- and post-operation, regardless of group. The study concludes the two months physiotherapeutic rehabilitation protocol for total knee arthroplasty is as effective as the three months protocol, as both reached the same goals and results

Nesta dissertação avaliamos o pico de torque da máxima contração voluntária de diferentes grupos musculares do membro operado e não operado em pacientes submetidos à ressecção de tumores ósseos e reconstrução com endopróteses do joelho (17 pacientes) ou do quadril (11 pacientes). Foi comparado o torque do lado acometido com o não acometido e, no caso do joelho, a redução do torque das ressecções distais do fêmur (8 pacientes) com as proximais da tíbia (9 pacientes). A redução do torque dos grupos musculares responsáveis pelo movimento das articulações estudadas foi definida como a proporção da diferença entre o lado acometido e o não acometido em relação ao torque do lado não acometido. No joelho houve redução do torque extensor de 77,5% e flexor de 29,1%. Não foi encontrada diferença na redução dos torques extensor e flexor entre ressecções proximais da tíbia e distais do fêmur apesar da necessidade de reinserção do ligamento patelar no primeiro caso. A reabilitação apresentou correlação inversa e moderada com a redução do torque, mostrando a importância da atividade física para manutenção ou melhora da força muscular. Nas reconstruções do quadril houve redução de todos os grupos musculares avaliados, sendo maior para os abdutores (39%), que foi o único grupo muscular reinserido à prótese com sutura. Apesar dos resultados funcionais bons e excelentes obtidos pelo questionário Musculoskeletal Tumor Society Rating Scale (MSTS) houve redução significativa da força para todos os grupos musculares estudados. Este estudo é original na medida em que o estudo das forças musculares é pouco explorado nas endopróteses do joelho e inédito nas endopróteses do quadril. Concluímos que não houve diferença significativa da redução da força muscular quando comparadas ressecções do fêmur distal e da tíbia proximal e que a altura da patela, o surgimento de complicações e o tempo de seguimento não influenciaram a redução da força muscular nas ressecções do joelho, mas o maior tempo de reabilitação melhorou o desempenho muscular. Nas reconstruções do quadril a redução da força ocorreu em todos os grupos musculares avaliados, sendo maior para os abdutores (39%). A redução do torque abdutor mostrou ter correlação com os resultados obtidos na avaliação do questionário MSTS. / In this dissertation, the peak torque of the maximum voluntary contraction of different muscle groups of the operated and non-operated limbs was measured in patients submitted to bone tumors resection and reconstruction with knee (17 patients) or hip (11 patients) endoprosthesis. The affected side was compared to the contralateral side and the torque deficit ratio was used to compare distal femur and proximal tibia resections. The torque deficit ratio was defined as the ratio of the torque difference between the affected and non-affected sides in relation to the non-affected side torque. Extension torque deficit ratio of the knee was 77,5% and flexor torque deficit ratio was 29,1%. No difference was found in extensor and flexor torque deficit ratios between distal femur (8 patients) and proximal tibia (9 patients) resections despite the need for reinsertion of the patellar ligament in the latter case. Rehabilitation presented an inverse and moderate correlation with torque deficit ratio, showing the importance of physical activity for maintenance or improvement of muscle strength. Strength reduction was seen in all muscle groups after hip reconstruction and was more intense in abductor muscles (39,0%), which was the only muscle group reinserted to the prosthesis with suture. Despite the good and excellent functional results obtained from the Musculoskeletal Tumor Society Rating Scale (MSTS), there was a significant strength reduction of all studied muscle groups. The need for muscular reinsertion and biomechanical factors did not affect the torque deficit ratio. Muscular strength has been scarcely studied after implantation of knee endoprosthesis and never after hip endoprosthesis which turns this study original. We concluded that there was no significant difference of muscle strength deficit when comparing distal femur and proximal tibia resections and that patellar height, complication upset, and follow-up time did not influence muscle strength in the knee resections, but longer rehabilitation time improves muscle performance in knee reconstructions. In hip reconstructions, the force reduction occurred in all muscle groups evaluated, being higher for the abductors (39,0%). Abductor torque reduction was shown to correlate with the results obtained in the MSTS questionnaire.

Bakgrund: Ledrörelse- och belastningsrestriktioner är vanliga efter en total höftprotesoperation och syftar till att undvika att höftleden luxerar eller att suturerad muskulatur släpper under tiden som mjukdelarna läker, vanligen 6 – 8 veckor. Proteser och operationsteknikerna har förändrats med åren vilket lett till att antalet postoperativa luxationer minskat, och därav har vissa ortopedkliniker i Sverige börjat frångå postoperativa ledrörelse- och belastningsrestriktioner. Syfte: Att kartlägga vilka ledrörelse- och belastningsrestriktioner som rekommenderas efter en total höftprotesoperation på svenska ortopedkliniker samt om restriktionerna har förändrats under de senaste fem åren. Metod: Studien genomfördes som en kvantitativ tvärsnittsstudie med hjälp av en egenformulerad validerad webbenkät. Huvudresultat: Av de 16 svarande klinikerna uppgav 81 % att de hade någon form av restriktion (ledrörelse- eller belastningsrestriktion) för sina höftprotesopererade patienter. Vanligast var ledrörelserestriktioner där 62 % av respondenterna svarade ja på frågan ”rekommenderar din enhet/klinik patienter som opereras med höftprotesoperation några ledrörelserestriktioner”. Motsvarande siffra för belastningsrestriktioner var 50 %. En total avsaknad av restriktioner förekom hos 19 % av de svarande klinikerna. 63 % av klinikerna svarade att belastningsrestriktionerna hade förändrats för mer än 10 år sedan medan 50 % av klinikerna svarade att ledrörelserestriktionerna hade förändrats de senaste 5 åren. Resultatet i vår studie tydde på att användandet av postoperativa restriktioner har minskat. Den vanligaste förändringen var en minskning av användandet av postoperativa ledrörelserestriktioner, vilket hade skett hos 60 % av respondenterna. Konklusion: Vår studie visade att 4 av 5 svenska ortopedklinikerna som deltog i vår enkätstudie använde sig av ledrörelse- eller belastningsrestriktioner efter en höftprotesoperation och att 1 av 5 inte använde restriktioner. Hälften av klinikerna har förändrat ledrörelserestriktionerna de senaste fem åren, och färre än 40 % har förändrat belastningsrestriktionerna. / Background: Joint movement- and load precautions are common after a total hip arthroplasty and aims to prevent dislocation of the hip and to prevent the loss of sutured muscles while the soft tissue heal, usually 6-8 weeks. Prosthesis and surgical technics have changed over the years, which had led to a reduced number of postoperative hip dislocations and hence have some orthopedic clinics in Sweden begun abandon postoperative joint movementand load precautions. Aim: A mapping of the use of joint movement- and load precautions in Swedish orthopedic clinics and if there has been any changes in precautions during the last five years. Method: The study was conducted as a quantitative cross-sectional study with the help of a selfdeveloped validated online survey. Result: 81 % of the 16 respondent clinics stated they had some form of precautions (joint movement- or load precautions) for their hip replaced patients. The most common precaution was joint movement where 62% of respondents answered yes to the question "Does your unit/Clinic recommend patients undergoing surgery with total hip replacement any joint movement precautions". The corresponding figure for load precautions was 50%. A total absence of restrictions occurred in 19 % of the respondent clinics. 63 % responded that modifications of load precautions took place for more than 10 years ago while 50 % responded that the modifications of joint movement precaution took place over the past 5 years. The result in our study indicated that the use of precautions had decreased. The most common change was a decrease in jointmovementprecautions that occurred with 60 % of the respondents. Conclusion: In our study we found that 4 out of 5 Swedish orthopaedic clinics who participated in our survey recommended joint movement- or load precautions after a hip replacement and it also showed that 1 out of 5 didn´t recommend precautions. Half of the clinics had changed the movement precautions during the past five years, and less than 40 % had changed the load precautions.

Discharge readiness following total knee replacement (TKR) has often been defined using quantitative factors, such as knee range of motion or walking a specified distance. These measurements fail to include other features that could impact readiness for discharge, such as social support or patient perceptions. Most patients have positive results following TKR surgery, however others experience negative outcomes such as falls, reduced functional performance, and hospital readmission. Readiness for returning home after TKR begins with pre-operative education to prepare patients for surgery and the post-operative phase. Health care providers must have a clear understanding of patients’ perceptions of readiness to return home after surgery. It is also essential to describe the current structure of pre-operative education nationally as a mechanism for better preparing patients to return home following knee replacement. This dissertation includes three studies that explore aspects of discharge readiness following TKR including patients’ perceptions of readiness for discharge as well as the structure of pre-operative education for TKR across the United States. The first study examined patients’ experiences preparing for discharge home from the acute care setting following TKR surgery. Results indicated that patients felt prepared overall for discharge and received appropriate supports for returning home after surgery, but some felt unprepared for certain aspects of recovery such as the amount of pain experienced in the post-operative phase. The second study surveyed health care providers who participated in pre-operative education before TKR to identify the current structure of education programs in the United States. This pilot study revealed that pre-operative education teams were commonly interprofessional with education being typically provided in a group format in a single session lasting between 1 and 1.5 hours. Verbal and written instruction were common delivery methods to provide education. The final dissertation study used mixed-methods to explore the current structure of pre-operative education for TKR in the United States with a large, national sample. Orthopedic nurses completed an online survey to describe their pre-operative education program. The majority of participants provided pre-operative education as part of interprofessional teams in either a group format or a format that included both group and individual education. Verbal instruction was the most common educational delivery method followed by written instruction. Most pre-operative education classes lasted between 1 and 1.5 hours, were delivered in a single session, and included a variety of topics. Ten orthopedic nurses were then interviewed and interview transcripts were analyzed qualitatively for common themes among participants. Participants expressed that pre-operative education was a significant component impacting patient outcomes following surgery. Interprofessional pre-operative education was valued by participants, but pragmatic factors were identified as barriers to the inclusion of other disciplines within these programs. Education programs were constantly evolving based on current evidence-based practice and changes to orthopedic protocols. Descriptions of pre-operative programs nationally combined with providers’ perceptions provides a strong basis for determining best practice to support better post-operative patient outcomes. This dissertation research culminated in recommendations for best practice as well as the creation of a model, the ICF-I-EDUCATE, which combines the International Classification of Health, Functioning and Disability (ICF), interprofessional practice, and the EDUCATE model for providing patient and family education. Research is needed to examine the ICF-I-EDUCATE model in clinical practice for patients with planned TKR.

Hip resurfacing arthroplasty has changed the treatment of end stage arthritis without severe deformity for young, active adults. Presently, there are varying clinical approaches to implant design selection and cementation techniques. The purpose of this project is to determine what amount of reamer-femoral component offset allows for the best cement penetration into the femoral head. Rapid prototyped femoral component models were produced with reamer femoral component offsets of 0.0 mm, 0.5 mm, and 1.0 mm. After implantation onto models of reamed femoral heads made from high-density open-cell reticulated carbon foam, cement penetration was assessed from cross-sections of the foam-implant unit. Increased offset was found to decrease the extent of cement over penetration from the dome and chamfer. Increased offset also yielded optimal cement penetration as measured from the walls. Finally, increased offset was found to increase the height of cement mantle formation while maintaining complete seating of all implants.

<p>Vid operation av primär total höftplastik finns det olika metoder för postoperativ smärtlindring. En tidigare genomförd studie på ett mellansvenskt sjukhus (nedan kallad ”höftprojektet”) visade att ”Local infiltration analgesia” (LIA) initialt minskade postoperativ smärta, underlättade mobilisering samt förkortade vårdtiden, jämfört med spinalt morfin. I denna studie genomfördes en långtidsuppföljning av höftprojektet med mätningar efter 6 respektive 12 veckor. Studiegruppen hade fått LIA vid operationsslutet och kontrollgruppen spinalt morfin. Båda grupperna hade en spinal bedövning under operationen. Denna långtidsuppföljning genomfördes med hjälp av journalgranskning och hade en deskriptiv och jämförande design med en kvantitativ ansats. Studiegruppen bestod av 40 patienter och kontrollgruppen 11 patienter. Studerade variabler var smärta mätt genom Visuell Analog Skala (VAS), behov av analgetika och mobilisering. Resultatet visade att det inte fanns någon signifikant skillnad mellan de båda grupperna när det gäller mobilisering under ett längre perspektiv. Det fanns dock en signifikant skillnad när det gäller smärta efter 3 månader, då studiegruppen uppgav en lägre grad av smärta än kontrollgruppen.</p> / <p>There are several methods for postoperative pain treatment after primary total hip replacement. It was shown in a earlier study at a Swedish hospital (below named as "the hip project") that "Local infiltration analgesia" (LIA) decreased pain, facilitated early postoperative mobility and earlier discharge from the hospital, compared with spinally administered morphine. Present study is a long term follow up of the hip project with two measures at 6 and 12 weeks. The study group was given LIA towards the end of the operation while the control group were given spinal morphine at the induction. Both groups had spinal analgesia during the surgery. The long term follow up was conducted by a comparative design and the data was collected from the patient’s charts and files. The variables were pain measured by Visual Analogous Scale (VAS), need of pain relieves and general mobility. The study group contained of 40 patients and the control group of 11. The result relived no significant differences between the two groups regarding long term mobility. There was, however, a significant difference in pain after 12 weeks; the study group had less pain that the control group.</p><p> </p><p> </p>

Displaced femoral neck fractures comprise more than a third of all hip fractures. There is controversy as to the optimal treatment. Despite attempts to improve the methods for internal fixation, complication rates have been almost unchanged: 20-40% non-union and late segmental collapse in another 10-20%. Internal fixation has been the preferred treatment in Scandinavia, whereas primary hemi- or total arthroplasty have been more prevalent in the rest of Europe and North America. In this study, patients 75 years or older, including those with mental impairment, were randomized to either internal fixation or cemented primary total hip arthroplasty (THA). A total of 146 hips in 143 patients were followed for two years. After one year 23% had died, and after two years 29%. Mortality was about the same in both groups. The accumulated mortality was pronounced among the mentally impaired patients. In the internal fixation group, 44% underwent further surgery. In the THA group, 18% dislocated. The dislocation rate was higher for the mentally impaired patients. The Harris hip scores were higher in the THA group, whereas pain was more common in the internal fixation group. The first 50 patients in each treatment group were studied concerning heterotopic ossification (HO), a well-known complication after THA. The incidence of HO in the THA group was similar to what is found after THA due to osteoarthritis. However, only 1/39 developed severe symptoms. A subgroup of 100 patients was included in a study concerning nutritional status and functional capacity using the Modified Norton scale, Katz index of ADL and a questionnaire measuring instrumental activities of daily living. The THA group fared better concerning weight change over time, locomotion and pain. The nutritional intervention did not show any measurable effects. All patients were followed until two years postoperatively and all fracturerelated hospital costs, including reoperations, were calculated. We found no difference in total costs between the treatment groups. Costs to the municipality were calculated comparing the baseline cost before surgery with the average cost per month during the first postoperative year. No difference was found between the treatment groups. On the basis of our results, we recommend arthroplasty for patients in this age group with normal mental function and high functional demands.

Greater trochanteric pain (GTP) is a regional pain syndrome characterized by lateral hip pain and tenderness. Its incidence after total hip arthroplasty (THA) is variable. Bursal inflammation, degenerative changes of the attachment of the gluteal muscles, direct operative trauma and biomechanical disturbance of the operated hip have been discussed as being related to GTP. The diagnosis is purely clinical because radiological and laboratory investigations show no definite pathology. Although most treatment modalities are conservative, some patients may develop refractory complaints leading to surgical intervention. In study I we studied the incidence of GTP in 172 consecutive patients who underwent THA during 2002 at Sundsvall Hospital. Patients with GTP (n=21, incidence 12%) were matched with controls from the same cohort. The THA outcome was assessed using the Western Ontario and McMaster Universities Arthrosis (WOMAC) Index. Trochanteric tenderness was studied using an electronic pressure algometer. We found an association between the occurrence of GTP and postoperative uncorrected lengthening of the operated limb of ≥ one centimetre. The WOMAC index revealed a reduction of the clinical outcome in the GTP group. In Study II we tested the value of using an algometer in the diagnosis of GTP after THA. We measured the pressure-pain threshold (PPT) over the greater trochanter and ilio-tibial band in 18 patients and 18 matched controls. Both groups were evaluated using the visual analogue scale (VAS). We found the algometer to have a good predictive validity and reproducibility. However, there was large inter-individual variability across subjects. The PPT ratio of 0.8 (affected vs. unaffected side) can be used as a cutoff ratio to establish GTP. There was no correlation between PPT measurements and VAS. Because of a low positive predictive value and large inter-individual variability, the pressure algometer has a limited value as a screening tool. In study III we proposed a new surgical treatment for refractory GTP after THA consisting of distal lengthening of the ilio-tibial band (ITB) by Z-plasty under local anaesthesia. This method was used in 12 women between March 2004 and June 2006. The patients were followed up by phone interview 3-4 months postoperatively and by an EQ-5D questionnaire and clinical examination including evaluation with the algometer at 1-3 years postoperatively. We found that the patients‘ quality of life was markedly improved following the operation (EQ-5D = 0.26 preoperatively vs. 0.67 postoperatively; p &lt;0.005). There were no postoperative complications. In study IV we evaluated the accuracy of a commonly used clinical method of LLD measurement (anterior superior iliac spine-medial malleolus) by comparing it to a reliable radiological method (tear drop-lesser trochanter) in 139 patients before and after THA. We found the correlation between the clinical and radiological methods to be weak preoperatively (r=0.21, ICC= 0.33) while the correlation was moderate postoperatively (r= 0.45, ICC=0.62). It is therefore recommended that the radiological method be used to measure leg length discrepancy in patients who undergo THA.