Every year, about 1 million patients worldwide and 16000 patients in Sweden undergo total hip arthroplasty (THA). This surgical intervention is considered a successful, safe and cost-effective procedure to regain pain-free mobility and restore hip joint function in patients suffering from severe hip joint disease or trauma. Besides relieving the pain, restoration of biomechanical forces around the hip with appropriate femoral offset (FO), leg length and proper component position and orientation are important goals. The radiographic preoperative planning and postoperative evaluation of these parameters require good validity, interobserver reliability and intraobserver reproducibility. It remains controversial as to how much postoperative leg length discrepancy (LLD) and FO change are acceptable. Generally, lengthening of the operated leg ≥ 10mm and FO reduction of the operated hip > 5mm should be avoided by using preoperative radiological templating and intraoperative measurement methods. There is no consensus on the association between LLD and FO and outcome after THA. The aims of this thesis were to: 1. To determine the influence of non-corrected LLD after THA on patients’ reported hip function and quality of life (QoL). 2. To study the association of global FO changes after THA with patients’ reported hip function, QoL and abductor muscle strength. 3. To evaluate the concurrent validity of the Sundsvall method of measuring postoperative global FO by comparing it to a standard method and to evaluate the interobserver reliability and intraobserver reproducibility of measurement of postoperative global FO, LLD and acetabular cup inclination and anteversion. 4. To analyse the postoperative radiographs of THA patients with leg lengthening and FO reduction to determine whether the problem is located in the stem, cup or both. Study I: A prospective cohort study of 174 patients with unilateral osteoarthritis (OA), comparing patients with lengthening ≥ 10mm, restoration (between 9 mm lengthening and 5 mm shortening) or shortening > 5 mm of the operated leg after THA. Follow up was 12–15 months. We found that a LLD of up to 20 mm did not influence the functional outcome (WOMAC) or QoL (EQ-5D). However, the lengthening group showed less improvement in WOMAC and more use of a shoe lift. Study II: A prospective cohort study of 222 patients with unilateral hip OA, comparing patients with decreased global FO (> 5 mm reduction), restored FO (within 5 mm restoration), and increased FO (> 5 mm increment) after THA. Follow up was was 12–15 months. The unadjusted results showed that the decreased FO group had a worse WOMAC index, less abductor muscle strength, and more use of walking aids. When these results were adjusted for possible confounding factors, only global FO reduction was statistically significantly associated with reduced abductor muscle strength. The incidence of residual hip pain and analgesics use was similar in the 3 groups. Study III: A prospective cohort study of 90 patients with primary unilateral OA treated with THA. Global FO using the Sundsvall method, global FO (standard method), LLD, acetabular cup inclination and anteversion were measured on postoperative radiographs. The interobserver reliability and intraobserver reproducibility were tested using three independent observers. We found that the Sundsvall method is as reliable as the standard method and the evaluated radiographic measurement methods have the required validity and reliability to be used in clinical practice. Study IV: A prospective cohort study of 174 patients with unilateral primary OA treated with THA. LLD and global FO were measured on postoperative radiographs. Patients with lengthening of the operated leg ≥ 10mm (n=41) and patients with reduction of global FO > 5mm (n=58) were further studied to investigate the amount of lengthening and global FO reduction that took place in the stem and in the cup compared with the contralateral side. The interobserver reliability and intraobserver reproducibility were tested using two independent observers. We found that post-THA lengthening of the operated leg ≥ 10mm was mainly caused by improper placement of the femoral stem, whereas a decrease of global FO > 5 was caused by improper placement of both acetabular and femoral components. The radiological measurement methods used showed substantial to excellent interobserver reliability and intraobserver reproducibility and are therefore clinically useful. The main conclusions of this thesis are: LLD up to 20 mm and reduced global FO more than 5 mm did not influence the functional outcome or quality of life at 12–15 months postoperatively. Lengthening ≥ 10mm was associated with increased use of a shoe lift. A reduction of global FO more than 5 mm compared to the contralateral hip was associated with weaker hip abductor muscles and more use of walking aids. Therefore both should be avoided. The radiographic measurement methods of LLD, global FO, cup inclination and anteversion have the required validity and reliability to be used in clinical practice. Lengthening of the operated leg is mainly caused by improper femoral stem positioning while global FO reduction results from improper positioning of both acetabular and femoral components. Surgeons should be aware of these operative pitfalls in order to minimize component malpositioning. / Varje år opereras ungefär 1 miljon patienter runt om i världen och 16000 patienter i Sverige med en total höftledsprotes (THA). Operation med höftledsprotes anses vara enav de mest framgångsrika, säkra och kostnadseffektiva kirurgiska åtgärderna med syfte att för att återställa livskvalité. Målet är att smärtlindra och återställa rörligheten i dendestruerade höftleden vid artros, reumatisk destruktion eller men efter exempelvis Perthes sjukdom. Vid operation med THA är det viktigt att återställa de biomekaniskakrafterna runt höftleden med en adekvat så kallad femoral offset (FO), postoperativ benlängdsskillnad (BLS) och ett tillfredsställande komponentläge. Den preoperativaplaneringen och den postoperativa bedömning av dessa parametrar kräver god tillförlitlighet, det vill säga validitet och reproducerbarhet både mellan olika bedömareoch vid upprepade mätningar av samma bedömare. Det är fortfarande inte klarlagt hur mycket postoperativ förändring i FO och BLS som är acceptabla. I dagsläget är detacceptabelt om den postoperativa benförlängningen understiger 1 cm och förändringen i FO är under 5 mm. Det finns ingen konsensus huruvida det föreligger ett sambandmellan BLS, FO och den patientrapporterade höftfunktionen och livskvalitén efter THA. Syftet med denna avhandling var: 1. Att studera effekten av icke-korrigerad BLS efter THA på den patientrapporterade höftfunktionen och livskvalitén. 2. Att studera effekten av förändringen i FO efter THA på den patientrapporterade höftfunktion, livskvalitén och muskelstyrka i abduktion. 3. Att utvärdera validitet och reliabilitet av en så kallad global FO genom att jämföra den med den gällande standard metoden samt studera tillförlitlighet av de radiologiskamätningar av postoperativa BLS, FO, cup inklination och anteversion efter THA. 4. Att radiologiskt undersöka i vilken av komponenterna (stam eller cup) somförändringen i FO och BLS verkar vara förlagd. Studie I: En prospektiv kohortstudie med 174 patienter som behandlats med THA för en primär unilateral koxartros. Patienterna delades in i tre grupper; de som fått en BLSförlängning över 10mm, återställning (mellan 9mm förlängning och 5mm förkortning) eller förkortning >5mm av det opererande benet efter THA. Uppföljning gjordes 12-15månader postoperativt. Vi fann att BLS upp till 20mm påverkade inte höftfunktion (WOMAC) och livskvalité (EQ-5D), men den förlängda gruppen visade en mindreförbättring i WOMAC och rapporterade en mer frekvent användning av skoinlägg. Studie II: En prospektiv kohortstudie med 222 patienter som behandlats med THA för en primär unilateral koxartros. Patienterna delades in i tre grupper; de patienter medförminskad FO (> 5mm minskning), återställd FO (inom 5mm) eller ökad FO (>5mm ökning). Uppföljning genomfördes efter 1 år med WOMAC, styrkemätning av höftensabduktorer och en frågeformulär. En minskad FO var associerade med en minskad styrka i höftens abduktorer. Det var ingen skillnad mellan grupperna gällandekvarstående höftsmärta och användning av analgetika. Studie III: En prospektiv kohortstudie med 90 patienter som behandlats med THA på grund av primär unilateral koxartros. På de postoperativa röntgenbilderna uppmättesglobala FO (Sundsvalls metodologi), globala FO (standard metod), BLS, cup inklination och anteversion. Reliabilitet och reproducerbarhet bedömdes mellan treoberoende observatörer. Vi fann att global FO (enligt Sundsvalls metodologi) är lika tillförlitlig som den nuvarande standardmetoden och de utvärderade radiologiskamätmetoderna har hög validitet och reliabilitet och kan således användas i klinisk praxis. Studie IV: En prospektiv kohortstudie med 174 patienter som behandlats med en THA för en primär unilateral koxartros. På de postoperativa röntgenbilderna uppmättes BLSoch globala FO. Patienter med förlängning ≥ 10mm (n=41) och patienter med minskning av globala FO >5mm (n=58) studerades for att mäta förlängning ochglobala FO minskning som sitter i stammen eller i cup jämfört med kontralaterala sidan. Reliabilitet och reproducerbarhet bedömdes av två oberoende observatörer. Vifann att en BLS över 10mm sitter framför allt i stamkomponenten i lårbenet medan en minskning i FO över 5 mm sitter i båda stam och cup. De radiologiska mätmetodernahar hög reliabilitet och reproducerbarhet och kan således användas i klinisk praxis. De viktigaste slutsatserna i denna avhandling är: 1. BLS med en förlängning upp till 20 mm och en minskning av globala FO mer än 5 mm påverkar inte patientrapporterad höftfunktion eller livskvalitet 1 år postoperativt. 2. BLS med en förlängning mer än 9 mm var associerad med mer användning av skoinlägg. En minskad FO med mer än 5 mm jämfört med den icke opererade höftenvar associerad med en sämre muskelstyrka i abduktion och ökat användning av gånghjälpmedel. 3. De radiologiska mätmetoderna av BLS, FO, acetabulära komponentens inklination och anteversion har hög validitet och reliabilitet, vilket kan användas i klinisk praxis. 4. En förlängning av det opererade benet orsakas främst av en positioneringen av stamkomponenten i lårbenet medan förlust av FO beror på otillfredsställande placeringav både stam och den acetabulära komponenten. Kirurger bör vara medveten om dessa operativa fallgropar för att optimera det kirurgiska resultatet.

Every year 16 000 individuals receive a total hip arthroplasty (THA) in Sweden. Even though THA is a common procedure, adverse events do occur. The most dramatic complication is death in the postoperative phase. The overall aim of this thesis was to describe and investigate early mortality after THA in Sweden. Sweden has an ideal platform for national observational registry studies, thanks to the use of personal identity numbers. Operation-specific information was collected from the Swedish Hip Arthroplasty Register, medical information from the National Board of Health and Welfare, and socioeconomic information was collected from Statistics Sweden. Main outcome was 90-day mortality. Study I was a prospective observational register study investigating the risk of mortality after a simultaneous bilateral THA compared with staged bilateral THA. There was no clinically relevant difference in early postoperative mortality between the two groups. Studies II and III were nation-wide matched cohort studies, with adjustment for comorbidity and socioeconomic background. Adjusted early mortality in femoral neck fracture patients receiving a THA is about double compared with a matched control population. Young (60-69 years) femoral neck fracture patients receiving a THA have a low absolute mortality risk, while those who are older than 80 years with a higher degree of medical comorbidity run a high risk of early death (II). In study III healthier, younger patients with higher socioeconomic status tended to be selected for cementless THA, resulting in selection bias. Even after accounting for this bias, however, there remains a small absolute and adjusted increase in the risk of death within 14 days after elective THA surgery using fully cemented implants. Study IV was a nationwide prospective cohort study comparing different comorbidity measures in terms of predicting early postoperative mortality after THA. A less data-demanding comorbidity measure is better at predicting 90-day mortality than more commonly used coding algorithms. In conclusion, socioeconomic background and the presence of comorbidities have an important influence on early mortality after THA, while the type of fixation is of less importance. Future mortality studies could benefit from the use of data that are routinely collected, and thus avoid the logistically complicated procedure now necessary to merge national databases.

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.

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.

Background: Total hip replacement (THR) with post-operative surveillance is recommended for debilitating osteoarthritis (OA). Using self-reported pain, function or walking performance is one alternative to address increasing surveillance demands. Objective: A cross-sectional cohort study to evaluate the associations of pain, function and performance with two radiographic markers of potential THR failure. Participants: 110 patients, median 6 years after THR surgery for OA. Methods: Questionnaires assessed demographics, co-morbidity, arthritis severity, pain, pain catastrophizing, and functional status. Performance was measured using the six minute walk test. THR outcome was assessed radiographically. Results: Few patients had pain, functional impairment or radiographic markers of potential THR failure. A larger percentage of patients with some intermittent pain (10.7 versus 8.6%) and pain iii after walking performance (40.0 versus 27.6%) had higher wear, but these differences were not significant. Conclusion: Measures of pain are potentially important for larger studies aiming to develop alternative methods of post-operative surveillance.

Background: Total hip replacement (THR) with post-operative surveillance is recommended for debilitating osteoarthritis (OA). Using self-reported pain, function or walking performance is one alternative to address increasing surveillance demands. Objective: A cross-sectional cohort study to evaluate the associations of pain, function and performance with two radiographic markers of potential THR failure. Participants: 110 patients, median 6 years after THR surgery for OA. Methods: Questionnaires assessed demographics, co-morbidity, arthritis severity, pain, pain catastrophizing, and functional status. Performance was measured using the six minute walk test. THR outcome was assessed radiographically. Results: Few patients had pain, functional impairment or radiographic markers of potential THR failure. A larger percentage of patients with some intermittent pain (10.7 versus 8.6%) and pain iii after walking performance (40.0 versus 27.6%) had higher wear, but these differences were not significant. Conclusion: Measures of pain are potentially important for larger studies aiming to develop alternative methods of post-operative surveillance.

Η αναθεώρηση μιας ολικής αρθροπλαστικής ισχίου λόγω χαλάρωσης του μηριαίου τμήματος της αποτελεί μια πρόκληση ακόμα και για πεπειραμένους χειρουργούς. Η άσηπτη χαλάρωση συνήθως σχετίζεται με κάποιο βαθμό οστικής απώλειας. Διερευνήσαμε εάν η πρόθεση Zweymüller SLR-Plus ®, μαζί με την βιολογική αναδόμηση με αλλομοσχεύματα του ελλειμματικού οστικού περιβάλλοντος του μηριαίου, θα επιτύγχανε επιβίωση, οστεοενσωμάτωση και σταθερότητα παρόμοια ή και καλύτερη από άλλες προθέσεις που χρησιμοποιούνται στη βιβλιογραφία για αναθεώρηση του μηριαίου τμήματος ΟΑΙ. Εξετάσαμε αναδρομικά 69 επιλεγμένους ασθενείς (70 ισχία) οι οποίοι υποβλήθηκαν σε αναθεώρηση του μηριαίου τμήματος με χρήση του SLR-Plus ® στειλεού σε μια περίοδο 10 ετών. Οι ενδείξεις για την αναθεώρηση περιελάμβαναν άσηπτη και σηπτική αποτυχία της βιολογικής στερέωσης, εσφαλμένη εμφύτευση, και περιπροθετικό κάταγμα. Επτά ασθενείς πέθαναν και τέσσερις χάθηκαν κατά το διάστημα παρακολούθησης. Πενήντα οκτώ από τους 69 ασθενείς (59 ισχία) ήταν διαθέσιμοι σε μέσο χρονικό διάστημα 8,3 ± 2,7 χρόνια (εύρος, 4-14 ετών) μετά τη χειρουργική επέμβαση αναθεώρησης. Υπήρχαν 14 άνδρες και 44 γυναίκες (μέση ηλικία, 69 έτη, εύρος, 42-89 ετών). Τέσσερις μηριαίες προθέσεις (7%) αναθεωρήθηκαν ξανά. Η 10ετής επιβίωση της πρόθεσης λαμβάνοντας ως αιτία αναθεώρησης την άσηπτη χαλάρωση ήταν 95% (95% C.I.: 86% -98%). Δεν παρατηρήθηκε περιπροθετική οστεόλυση του μηριαίου γύρω από την πρόθεση και 91% των SLR-Plus στειλεών εμφανίστηκε ακτινολογικά σταθερό είτε μέσω οστεοενσωμάτωσης είτε μέσω ινώδους στερέωσης. Με βάση τα στοιχεία επιβίωσης, πιστεύουμε ότι η χρήση του SLR-Plus® στειλεόυ είναι μια αξιόπιστη λύση για τους ασθενείς που υποβάλλονται σε χειρουργική επέμβαση αναθεώρησης ΟΑΙ, με απώλεια οστικής μάζας στο κεντρικό τμήμα του μηριαίου. / Revision after failed THA resulting from loosening of the femoral component can be challenging even for experienced surgeons. Aseptic loosening usually is associated with some degree of bone loss. We asked whether the Zweymüller SLR-Plus®, along with allograft reconstruction of the deficient femoral bone stock, would provide survivorship, osseointegration, and stability similar to or better than previously reported implants for femoral revision. We retrospectively reviewed 69 selected patients (70 hips) who underwent revision of the femoral component using the SLR-Plus® stem during a 10-year period. The indications for revision included aseptic and septic failure of biologic fixation, incorrect implantation, and periprosthetic fracture. Seven patients died and four were lost to followup. Fifty-eight of the 69 patients (59 hips) were available at a mean 8.3 ± 2.7 years (range, 4–14 years) after revision surgery. There were 14 men and 44 women (mean age, 69 years; range, 42–89 years). Four stems (7%) were rerevised. With rerevision for aseptic reasons, the survival at 10 years was 95% (95% confidence interval, 86%–98%). No femoral periprosthetic osteolysis occurred around the stem and 91% of stems appeared stable radiographically (osseointegration, fibrous). Based on the survival data, we believe the SLR-Plus® stems are reliable for patients undergoing hip revision surgery with central bone loss.

O presente estudo é uma coorte contemporânea de 49 pacientes (51 quadris) submetidos à reconstrução acetabular com enxerto ósseo liofilizado humano ou bovino, picado e impactado, associado a reforço acetabular. Foi realizado no Serviço de Ortopedia e Traumatologia do Hospital de Clínicas de Porto Alegre (HCPA), no período de maio de 1997 a fevereiro de 2005. Os pacientes foram divididos em dois grupos: o grupo 1 (n=26) foi composto pelos que receberam enxerto ósseo liofilizado de origem humana e o grupo 2 (n=25), por aqueles que receberam enxerto de origem bovina. O reforço utilizado em todos os casos foi da MDT® (SP-Brasil). O tempo médio de seguimento foi de 55 e 49 meses respectivamente. Os enxertos ósseos purificados e liofilizados foram produzidos pelo Banco de Tecidos do HCPA. A análise clínica baseou-se no escore de Merle d’Aubigné e Postel e a radiográfica, nos critérios de Conn et al.para osteointegração dos enxertos que avalia a radiolucência, a densidade, a formação de trabeculado ósseo e a migração do componente. Não foram encontradas diferenças clínicas ou radiográficas relevantes entre os grupos, obtendo-se em torno de 88,5 e 76% de integração do enxerto. Estes resultados são comparáveis aos relatados na literatura com o uso de enxerto alógeno congelado e estimulam a continuidade da pesquisa sobre enxertos liofilizados de origem humana e bovina. / Background: this is a cohort trial of 49 patients (51 hips) submitted to revision acetabular component of total hip arthroplasty, using impacted human and bovine freeze-dried cancellous bone grafts and reinforcement device. The study was carried out in the Hospital de Clínicas de Porto Alegre (HCPA) from May 1997 to February 2005. The aim of the study was to compare clinical and radiographic graft incorporation capability between human and bovine freeze-dried bone grafts. Patients and Methods: the patients were divided in two groups: Group 1 (n=26) was composed by those receiving human grafts, and Group 2 (n=25), bovine grafts. The follow-up average was 55 and 49 months. The grafts were purified and freeze-dried at the Tissue Bank of the HCPA.The clinical analysis was based on the score of Merle d’Aubigné and Postel; and the radiographic analysis in an established score based in Conn’s et al. criteria for radiographic bone incorporation. Results: no clinical or radiographic differences were observed between the groups and both groups showed an overall rate of 88.5 and 76% of graft integration. Conclusion: these results are comparable to those reported in the literature with the use of deep-frozen grafts. Therefore, bovine and human freeze-dried grafts can be safely and adequately used in acetabular revision in total hip arthroplasty.

A artroplastia é, em última análise, a opção final para o tratamento da osteoartrose. Com o aumento do número de indicações deste procedimento, a troca (artroplastia total de quadril de revisão – ATQR) dos componentes também passou a ser mais frequente. Os defeitos ósseos ou falhas ósseas são problemas que podem ser encontrados quando se realiza uma ATQR e, eles devem ser reparados, ou seja, o quadril do paciente a receber outra prótese necessita ser reconstruído. Para isto a grande maioria das técnicas empregadas requer o uso de enxerto ósseo e, devido a este motivo este tecido tem se tornado um dos tecidos mais transplantados na atualidade. Porém a demanda para utilização dos enxertos, na maioria provenientes de bancos de tecidos ósseos, tem aumentado, mas o suprimento é insuficiente. Portanto faz-se necessário a busca por novas tecnologias e alternativas aos bancos de tecidos. O enxerto bovino liofilizado (EBL) é uma destas opções, sua produção em livre demanda suas características físicas e químicas semelhantes ao osso humano e sua boa repercussão clínico-radiológica o torna uma alternativa viável. Este estudo tem o objetivo de verificar e quantificar a neoformação óssea com o uso do EBL pelo uso da avaliação histológica. Realizou-se um estudo de casos de Julho de 2000 a Abril de 2013 no Hospital de Clínicas de Porto Alegre (HCPA), onde se incluíram sujeitos que foram submetidos a uma cirurgia prévia cirurgia de ATQR onde foi utilizado o EBL os quais internaram posteriormente para uma segunda cirurgia de ATQR não relacionada a falha do enxerto e sim a falha da prótese. Nesta segunda cirurgia realizou-se a biópsia óssea. Quatorze sujeitos foram analisados, sendo 64,3% do sexo feminino. A média de idade dos pacientes foi 52,36±18,55. Neoformação óssea estava presente em 85,7% dos sujeitos, e constituiu 61,79% da área total de matriz óssea. O diagnóstico de absorção do EBL estava presente em 12 sujeitos. Uma forte correlação de proporção inversa foi constatada pelo teste de Pearson entre a porcentagem de osso neoformado e a porcentagem de EBL na área total de matriz óssea (p=0,001). Nenhuma resposta inflamatória foi encontrada. Concluiu-se que houve neoformação óssea adequada na grande maioria dos casos sendo o EBL uma boa estrutura osteocondutora, podendo ser considerado uma alternativa aos outros enxertos ósseos no tratamento das falhas ósseas. / Arthroplasty is, ultimately, the final option for the treatment of osteoarthritis. With the increasing number of indications of this procedure, the exchange (total hip arthroplasty revision surgery- THARS) also became more frequent. The bone defects are problems that can be encountered when conducting a THARS and this defect must be repaired, in other words, the patient's hip needs to be rebuilt before receive a new prosthesis. Most of techniques used to rebuild requires the use of bone graft, and because of this reason, this tissue has become one of the most transplanted tissues today. However the demand for the use of grafts, mostly from bone tissue banks, has increased, but the supply is insufficient. Therefore it is necessary to search for new technologies and alternatives to tissue banks. The bovine lyophilized xenograft (BLX) is one of these options; the production on free demand, its physical and chemical characteristics similar to human bone and its good clinical and radiological outcomes makes it a viable alternative. The aim of this study was to verify and quantify new bone formation by the histological analysis in subjects who received the BLX. This was a case series from July 2000 to April 2013 realized in the Hospital de Clínicas de Porto Alegre. This study included patients who underwent to a THARS where was used the BLX, which later was admitted to a second THARS surgery, not related to the xenograft failure but a mechanical failure of the implant. In this second surgery was performed the bone biopsy. Fourteen subjects were analyzed, 64.3% were female. The average age of patients was 52.36 ± 18.55 years. New bone formation was present in 85.7% of subjects, and constituted 61.79% of the total bone matrix. The diagnosis of BLX absorption was present in 12 subjects. A strong inverse correlation founded by the Pearson's test was observed between the proportion of new bone and the proportion of BLX (p=0.001). No inflammatory response was found. Was concluded that there was suitable bone formation in the vast majority of the cases, as well as the BLX is a good osteoconductive scaffold and can be considered an alternative to other bone graft in the treatment of bone defects.

O presente estudo é uma coorte contemporânea de 49 pacientes (51 quadris) submetidos à reconstrução acetabular com enxerto ósseo liofilizado humano ou bovino, picado e impactado, associado a reforço acetabular. Foi realizado no Serviço de Ortopedia e Traumatologia do Hospital de Clínicas de Porto Alegre (HCPA), no período de maio de 1997 a fevereiro de 2005. Os pacientes foram divididos em dois grupos: o grupo 1 (n=26) foi composto pelos que receberam enxerto ósseo liofilizado de origem humana e o grupo 2 (n=25), por aqueles que receberam enxerto de origem bovina. O reforço utilizado em todos os casos foi da MDT® (SP-Brasil). O tempo médio de seguimento foi de 55 e 49 meses respectivamente. Os enxertos ósseos purificados e liofilizados foram produzidos pelo Banco de Tecidos do HCPA. A análise clínica baseou-se no escore de Merle d’Aubigné e Postel e a radiográfica, nos critérios de Conn et al.para osteointegração dos enxertos que avalia a radiolucência, a densidade, a formação de trabeculado ósseo e a migração do componente. Não foram encontradas diferenças clínicas ou radiográficas relevantes entre os grupos, obtendo-se em torno de 88,5 e 76% de integração do enxerto. Estes resultados são comparáveis aos relatados na literatura com o uso de enxerto alógeno congelado e estimulam a continuidade da pesquisa sobre enxertos liofilizados de origem humana e bovina. / Background: this is a cohort trial of 49 patients (51 hips) submitted to revision acetabular component of total hip arthroplasty, using impacted human and bovine freeze-dried cancellous bone grafts and reinforcement device. The study was carried out in the Hospital de Clínicas de Porto Alegre (HCPA) from May 1997 to February 2005. The aim of the study was to compare clinical and radiographic graft incorporation capability between human and bovine freeze-dried bone grafts. Patients and Methods: the patients were divided in two groups: Group 1 (n=26) was composed by those receiving human grafts, and Group 2 (n=25), bovine grafts. The follow-up average was 55 and 49 months. The grafts were purified and freeze-dried at the Tissue Bank of the HCPA.The clinical analysis was based on the score of Merle d’Aubigné and Postel; and the radiographic analysis in an established score based in Conn’s et al. criteria for radiographic bone incorporation. Results: no clinical or radiographic differences were observed between the groups and both groups showed an overall rate of 88.5 and 76% of graft integration. Conclusion: these results are comparable to those reported in the literature with the use of deep-frozen grafts. Therefore, bovine and human freeze-dried grafts can be safely and adequately used in acetabular revision in total hip arthroplasty.