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No description available.

The purpose of this dissertation was to study the effects of graft pretension in anterior cruciate ligament (ACL) reconstruction through a series of experiments. First, an in vitro study of 5 human knees was conducted to determine if intact joint kinematics could be restored when using the ideal graft - the intrinsic ACL. The ACL tibial insertion site was freed, and pretensions of 0, 10, 20, 30, and 40 N were applied to the ligament using a custom designed load cell connection. Kinematics during a simulated active extension were compared to those of the intact knee. Intact knee kinematics were not restored. Pretensions that best restored tibial anterior/posterior translation and internal/external rotation ranged from 0-40 N. Furthermore, the pretensions that best restored these kinematic variables were widely disparate in two specimens. Second, the in vitro kinematics during a simulated active extension of human and porcine knees were compared and contrasted both prior to and following transection of the ACL. The ACL limited: (1) tibial anterior translation in both species, (2) tibial internal rotation in humans, and (3) tibial external rotation in pigs. Differences in kinematic patterns for tibial internal/external rotation and abduction/adduction between the species was explained by requirements for biped and quadruped stances. Third, the mechanical characteristics of porcine patellar tendon (PT) were investigated by uniaxial tensile testing at two strain rates. Patella-PT-tibia complexes from freshly sacrificed skeletally immature and mature animals were loaded to failure at elongation rates of 20 and 200 mm/min. Both strain rate and skeletal maturity significantly affected failure mode, tangent modulus, and ultimate stress of the tendons, and hence are important considerations in the mechanical evaluation of porcine PT. Fourth, ACL reconstructions were performed using pretensions of 10 or 20 N in an in vivo porcine model with a specially designed load cell/telemetry system to monitor graft load. Graft pretension was seen to increase during fixation with interference screws. Following sacrifice at 4 weeks, tissues were mechanically, histologically, and biochemically analyzed. A pretension of 20 N resulted in a tissue more similar to the intrinsic ACL. / Ph. D.

Objective: To evaluate the relative position of the femur and tibia in cranial cruciate ligament (CCL) intact stifles, CCL deficient stifles, and stifles following a novel extracapsular procedure (lateral extracapsular suture system or LESSa) under load at specific joint angles. Study Design: In vitro biomechanical study. Methods: Twenty pelvic limbs from 11 dogs were used to evaluate the relative position of the femur and tibia between 3 stifle conditions (CCL intact, CCL deficient, and LESSa treated) at a load of 30 % and stifle angles of 125", 135", and 145" using electromagnetic tracking sensors. Results: Cranial cruciate ligament deficient stifles had significantly greater (p <0.0001) cranial displacement and internal rotation of the tibia relative to the femur than CCL intact stifles or LESSa treated stifles at all stifle angles. Cranial displacement of the tibia relative to the femur for CCL intact and LESSa treated were not significantly different from one another at stifle angles of 125", but were significantly different at stifle angles of 135" (p = 0.0182) and 145" (p = 0.0012). There was no significant difference in internal rotation of the tibia relative to the femur between CCL intact and LESSa treated stifles at any of the stifle angles. Conclusion: LESSa effectively decreases cranial tibial displacement and eliminates internal rotation of the tibia relative / Master of Science

Objectives: To compare optical values in the osteotomy gap created after a Tibial Tuberosity Advancement (TTA) treated with autogenous cancellous bone graft (ACBG), extracorporeal shock wave therapy (ESWT), a combination of ACBG and ESWT, and absence of both ACBG and ESWT using densitometry. Methods: Dogs presenting for surgical repair of a cranial cruciate ligament rupture were randomly assigned to one of four groups; TTA with ACBG (TTA-G), TTA with ACBG and ESWT (TTA-GS), TTA with ESWT (TTA-S), and TTA with no additional therapy (TTA-O). Mediolateral radiographs at 0, 4 and 8 weeks after surgery were evaluated to compare healing of the osteotomy gap via densitometry. An analysis of variance (ANOVA) statistical analysis was used to compare the densitometric values between groups. Results: At 4 weeks after surgery, a significant difference in osteotomy gap density was noted between TTA-GS (8.4 millimeters of Aluminum equivalent [mmAleq]) and TTA-S (6.1mmAleq), and between TTA-GS (8.4 mmAleq) and TTA-O (6.4 mmAleq). There were no significant differences noted between groups at the 8 week recheck. Clinical Significance: There were no significant differences in the osteotomy gap density at 8 weeks after surgery regardless of the treatment modality used. The combination of ACBG and ESWT may lead to increased density of the osteotomy gap in the first 4 weeks after surgery. Densitometry using an aluminum step wedge is a feasible method for comparison of bone healing after TTA in dogs. / Master of Science

<p>Ova studija je bila prospektivnog karaktera. Uz dopu&scaron;tenje etičkog komiteta Kliničkog centra Vojvodine istraživanje je sprovedeno na Klinici za ortopedsku hirurgiju i traumatologiju i obuhvatilo je 60 pacijenata mu&scaron;kog pola, koji su metodom slučajnog izbora na randomizirani način uključeni u ispitivanje, a koji se aktivno i profesionalno bave fudbalom, ko&scaron;arkom ili odbojkom,&nbsp; primljenih na Kliniku za ortopedsku hirurgiju radi artroskopske rekonstrukcije pokidanog prednjeg ukr&scaron;tenog ligamenta. U ispitivanje su uključeni samo oni pacijenti koji su dali potpisani informisani pristanak da učestvuju u ispitivanju, koji su zadovoljii sve kriterijume za uključivanje i koji nisu imali niti jedan kriterijum za isključivanje iz studije. Kriterijumi za uključivanje u studiju&nbsp; podrazumevali su sledeće: da je pacijent&nbsp; primljen na Kliniku za ortopedsku hirurgiju i traumatologiju Kliničkog centra Vojvodine u Novom Sadu radi operativnog lečenja prekida prednjeg ukr&scaron;tenog ligamenta kolena, da je potpisao informisani pristanak za uključivanje, da je starosne dobi od 18 do 45 godina, da se aktivno i profesionalno bave fizičkom aktivno&scaron;ću regulisanom pravilima (fudbal, odbojka, ko&scaron;arka). Kriterijumi za isključivanje pacijenata iz istraživanja bili su sledeći: prisustvo udružene povrede i spolja&scaron;njeg pobočnog ligamenta koja zahteva operativno lečenje, pojava težih op&scaron;te &ndash; hirur&scaron;kih komplikacija, želja pacijenta da bude isključen iz daljeg ispitivanja, bez obaveze da tu svoju odluku obrazloži. U prvoj fazi konstruisan je aparat, digitalni goniometar, uz pomoć kojeg je urađen eksperimentalni deo ovog ispitivanja i napravljena je baza podataka sa poljima za upis deskriptivnih i antropometrijskih parametara. Potom je uz pomoć aparata svim ispitanicima testirana sposobnost propriocepcije (JPS). Testiranje&nbsp; je obavljeno preoperativno na povređenom i nepovređenom ekstremitetu, u dva maha: odmah po zadavanju ciljnog ugla od 35&deg; i nakon 5 minuta. Druga faza je obavljena minimum 6 meseci nakon operativnog lečenja, hirur&scaron;kom, artroskopskom rekonstrukcijom pokidanog prednjeg ukr&scaron;tenog ligamenta kost-tetiva-kost tehnikom (bone-tendo-bone, BTB). Klinički pregled&nbsp; svakog pacijenta je podrazumevao proveru rezultata Lachman testa (pozitivan/negativan), Lysholm i IKDC bodovne skale za koleno i to preoperativno a potom i tokom postoperativnog kontrolnog pregleda. Po uzoru na mnoge sajtove renomiranih ortopedskih organizacija (http://www.orthopaedicscore.com/), naparavljen je on-line upitnik na Google drive-u gde su u elektronskom obliku prikupljani podaci za skale koje smo koristili. Dobijeni rezultati su za svaku skalu ponaosob potom prebacivani u Excel i dalje&nbsp; obrađivani adekvatnim statističkim alatkama u adekvatnom programu. U rezultatima je uočeno da dobijena razlika u preciznosti pozicioniranja potkolenice sa o&scaron;tećenim ligamentarnim aparatom kolena u odnosu na nepovređenu nogu pre hirur&scaron;ke rekonstrukcije prednjeg ukr&scaron;tenog ligamenta ne pokazuje statistički značajnu razliku. Međutim, postojala je statistički značajna razlika u brzini kojom se postiže zadati ugao, tj. povređena noga imala je veći intenzitet ugaonog uspona &scaron;to ukazuje na kvalitativne razlike u samom obrascu pokreta. Takođe, na ovom uzorku dobijeno je da postoji statistički značajna razlika u preciznosti pozicioniranja potkolenice sa o&scaron;tećenim ligamentarnim aparatom kolena u odnosu na nepovređenu nogu nakon hirur&scaron;ke rekonstrukcije prednjeg ukr&scaron;tenog ligamenta tj. pacijenti su nakon rekonstrukcije statistički značajno &raquo;prebacivali&laquo; zadatu vrednost od 35&deg;. Test pozicioniranja ekstremiteta za ovo ispitivanje konstruisanim aparatom se pokazao kao senzitivna i specifična dijagnostička procedura gubitka sposobnosti propriocepcije usled kidanja prednjeg ukr&scaron;tenog ligamenta.</p> / <p>In this prospective study examined group consisted&nbsp; of&nbsp; 60&nbsp; male&nbsp; patients&nbsp; with&nbsp; an anterior&nbsp; cruciate&nbsp; ligament&nbsp; tear&nbsp; and&nbsp; all participants&nbsp;&nbsp; were&nbsp;&nbsp; at&nbsp;&nbsp; the&nbsp;&nbsp; time&nbsp;&nbsp; before injury&nbsp;&nbsp; actively&nbsp;&nbsp; playing&nbsp;&nbsp; afootball, basketball&nbsp; or&nbsp; volleyball.&nbsp; The&nbsp; study&nbsp; was conducted&nbsp; at&nbsp; the&nbsp; Clinic&nbsp; for&nbsp; Orthopaedic Surgery&nbsp;&nbsp;&nbsp; and&nbsp;&nbsp;&nbsp; Traumatology&nbsp;&nbsp;&nbsp; Clinical Center&nbsp; of&nbsp; Vojvodina&nbsp; in&nbsp; Novi&nbsp; Sad&nbsp; where participants&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; were&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; admitted&nbsp;&nbsp; for arthroscopic ligament reconstruction. All participants&nbsp; were&nbsp; informed&nbsp; of&nbsp; the&nbsp; study by&nbsp;&nbsp; their&nbsp;&nbsp; clinicians&nbsp;&nbsp; and&nbsp;&nbsp; gave&nbsp;&nbsp; written consent. Thee exclusion criteria were the following:&nbsp;&nbsp;&nbsp; occurrence&nbsp;&nbsp;&nbsp; of&nbsp;&nbsp;&nbsp; combined cruciate&nbsp; ligament&nbsp; with&nbsp; lateral&nbsp; collateral ligament&nbsp;&nbsp; injury&nbsp;&nbsp; that&nbsp;&nbsp; required&nbsp;&nbsp; surgical treatment;&nbsp; occurrence&nbsp; of&nbsp; more&nbsp; serious general&nbsp;&nbsp;&nbsp; surgical complications; the patient&rsquo;s&nbsp; wish&nbsp; to&nbsp; be&nbsp; excluded&nbsp; from further&nbsp; research&nbsp; without&nbsp; an&nbsp; obligation&nbsp; to give&nbsp;&nbsp; any&nbsp;&nbsp; further&nbsp;&nbsp; explanation&nbsp;&nbsp; to&nbsp;&nbsp; his decision.&nbsp; In&nbsp; the&nbsp; first&nbsp; stage&nbsp; of&nbsp; the&nbsp; study, an&nbsp; apparatus&nbsp; called&nbsp; digital&nbsp; goniometer was&nbsp;&nbsp; constructed,&nbsp;&nbsp; which&nbsp;&nbsp; was&nbsp;&nbsp; used&nbsp;&nbsp; to conduct&nbsp;&nbsp; the&nbsp;&nbsp; experimental&nbsp;&nbsp; part&nbsp;&nbsp; of&nbsp;&nbsp; the study,&nbsp; and&nbsp; a&nbsp; database&nbsp; with&nbsp; fields&nbsp; for inserting&nbsp; descriptive&nbsp; and&nbsp; anthropometric parameters was made. Next, by using the apparatus,&nbsp; all&nbsp; subjects&nbsp; were&nbsp; tested&nbsp; for proprioception&nbsp; ability&nbsp; (JPS).&nbsp; The&nbsp; tests were&nbsp; performed&nbsp; preoperatively&nbsp; on&nbsp; the injured&nbsp; and&nbsp; the&nbsp; uninjured&nbsp; limb&nbsp; in&nbsp; two instances:&nbsp; straight&nbsp; after&nbsp; determining&nbsp; the target&nbsp;&nbsp; angle&nbsp; of&nbsp;&nbsp; 35&deg;&nbsp; and&nbsp;&nbsp; 5&nbsp;&nbsp; minutes afterwards.&nbsp;&nbsp;&nbsp; The&nbsp;&nbsp;&nbsp; second&nbsp;&nbsp;&nbsp; stage&nbsp;&nbsp;&nbsp; was performed&nbsp; postoperatively&nbsp; in&nbsp; the&nbsp; same maner,&nbsp;&nbsp; following&nbsp;&nbsp; a&nbsp;&nbsp; minimal&nbsp;&nbsp; 6-month period&nbsp;&nbsp;&nbsp; after&nbsp;&nbsp;&nbsp; a&nbsp;&nbsp;&nbsp; surgical&nbsp;&nbsp;&nbsp; arthroscopic reconstruction&nbsp;&nbsp;&nbsp; of&nbsp;&nbsp;&nbsp; the&nbsp;&nbsp;&nbsp; torn&nbsp;&nbsp;&nbsp; anterior cruciate&nbsp; ligament&nbsp; by&nbsp; bone-tendon-bone (BTB) technique. The clinical evaluation of&nbsp; each&nbsp; patient&nbsp; involved&nbsp; Lachman&nbsp; test (positive / negative), Lysholm and IKDC scales,&nbsp;&nbsp; first&nbsp;&nbsp; pre-operatively&nbsp;&nbsp; and&nbsp;&nbsp; then during&nbsp;&nbsp; post-operative&nbsp; check&nbsp; up assessment.&nbsp; Following&nbsp; the&nbsp; example&nbsp; of many&nbsp; websites&nbsp; or&nbsp; eminent&nbsp; orthopaedic organisations (http://www.orthopaedicscore.com/),&nbsp;&nbsp; an online&nbsp;&nbsp; survey&nbsp;&nbsp; was&nbsp;&nbsp; made&nbsp;&nbsp; on&nbsp;&nbsp; Google Drive,&nbsp;&nbsp;&nbsp;&nbsp; where&nbsp;&nbsp;&nbsp;&nbsp; data&nbsp;&nbsp;&nbsp;&nbsp; was&nbsp;&nbsp;&nbsp;&nbsp; collected electronically&nbsp; for&nbsp; the&nbsp; scales&nbsp; used.&nbsp; The results were then transferred to Excel for each&nbsp; scale,&nbsp; to&nbsp; be&nbsp; further&nbsp; processed&nbsp; by using&nbsp;&nbsp; adequate&nbsp;&nbsp; statistic&nbsp;&nbsp; tools&nbsp;&nbsp; in&nbsp;&nbsp; an adequate&nbsp;&nbsp;&nbsp;&nbsp; programme.&nbsp;&nbsp;&nbsp;&nbsp; The&nbsp;&nbsp;&nbsp;&nbsp; results indicated&nbsp; that,&nbsp; when&nbsp; compared&nbsp; with&nbsp; the uninjured&nbsp; leg,&nbsp; a&nbsp; resulting&nbsp; disparity&nbsp; in precision&nbsp; of&nbsp; positioning&nbsp; the&nbsp; lower&nbsp; leg with&nbsp; a&nbsp; damaged&nbsp; ligament&nbsp; apparatus&nbsp; of the&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; knee&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; before&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; the&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; surgical reconstruction&nbsp; of&nbsp; the&nbsp; anterior&nbsp; cruciate ligament&nbsp; was&nbsp; not&nbsp; considered&nbsp; statistically significant.&nbsp;&nbsp;&nbsp; However,&nbsp;&nbsp;&nbsp; there&nbsp;&nbsp;&nbsp; was&nbsp; a statistically&nbsp; significant&nbsp; difference&nbsp; in&nbsp; the speed&nbsp;&nbsp; of&nbsp;&nbsp; attaining&nbsp;&nbsp; a&nbsp;&nbsp; specified&nbsp;&nbsp; angle which indicates qualitative differences in the&nbsp; motion&nbsp; pattern&nbsp; itself.&nbsp; Furthermore, this&nbsp;&nbsp;&nbsp;&nbsp; sample&nbsp;&nbsp;&nbsp;&nbsp; study&nbsp;&nbsp;&nbsp;&nbsp; resulted&nbsp;&nbsp; in&nbsp; a statistically&nbsp; significant&nbsp; difference&nbsp; in&nbsp; the precision&nbsp;&nbsp; of&nbsp;&nbsp; positioning&nbsp;&nbsp; of&nbsp;&nbsp; lower leg&nbsp; with&nbsp;&nbsp;&nbsp;&nbsp; the&nbsp;&nbsp;&nbsp;&nbsp; damaged&nbsp;&nbsp; knee&nbsp; ligament apparatus&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; after&nbsp;&nbsp; the&nbsp;&nbsp; surgical reconstruction&nbsp; of&nbsp; the&nbsp; anterior&nbsp; cruciate ligament,&nbsp;&nbsp;&nbsp; when&nbsp;&nbsp;&nbsp; compared&nbsp;&nbsp;&nbsp; with&nbsp;&nbsp;&nbsp; the uninjured&nbsp; leg,&nbsp; i.e.&nbsp; after&nbsp;&nbsp; the reconstruction,&nbsp; the&nbsp; patients&nbsp;&nbsp; had&nbsp;&nbsp; a significantly&nbsp;&nbsp; higher&nbsp;&nbsp; degree&nbsp;&nbsp; of&nbsp;&nbsp; flexion than&nbsp;&nbsp; the&nbsp;&nbsp; targeted&nbsp;&nbsp; 35&deg;.&nbsp;&nbsp; The&nbsp;&nbsp; test&nbsp;&nbsp; for positioning&nbsp; extremities,&nbsp; performed&nbsp; with the&nbsp;&nbsp;&nbsp; specially&nbsp;&nbsp;&nbsp; constructed&nbsp;&nbsp;&nbsp; apparatus, proved&nbsp; to&nbsp; be&nbsp; a&nbsp; sensitive&nbsp; and&nbsp; specific diagnostic procedure for determining the loss&nbsp; of&nbsp; proprioceptic&nbsp; ability&nbsp; due&nbsp; to anterior cruciate ligament tear.</p>

INTRODUÇÃO: A lesão do ligamento cruzado anterior (LCA) é considerada uma lesão grave e pode afetar a carreira de um jogador de futebol profissional. O tratamento cirúrgico é frequentemente necessário para o tratamento da instabilidade. Embora a reconstrução do LCA seja considerada um procedimento eficaz em restaurar a estabilidade articular, a literatura mostra que apenas 55% dos atletas retornam à prática de esportes competitivos após a cirurgia. Jogadores de futebol profissional dependem de habilidades técnicas, táticas e físicas, como boa função do joelho e capacidade aeróbia. O objetivo deste trabalho é avaliar a capacidade aeróbia em jogadores profissionais de futebol de campo com lesão do LCA e após seis meses de reabilitação pós-operatória. MÉTODOS: Vinte jogadores profissionais de futebol de campo com lesão do LCA foram submetidos a reconstrução do LCA com tendões flexores autólogos e foram comparados com 20 jogadores profissionais de futebol de campo em atividade, sem histórico de lesão no joelho. Avaliamos a capacidade aeróbia máxima pelo consumo máximo de oxigênio (VO2max) e submáxima pelos limiares ventilatórios (LV1 e LV2), avaliados por ergoespirometria em esteira utilizando o protocolo de Heck modificado. Os testes foram realizados no pré-operatório e aos seis meses de pós-operatório e os resultados comparados ao grupo controle de jogadores profissionais em plena atividade. Também realizamos questionários de função subjetiva do joelho (Lysholm e IKDC), dinamometria isocinética computadorizada e avaliação da composição corporal por bioimpedância. RESULTADOS: No grupo com lesão do LCA a média da idade foi de 21,7 anos, enquanto no grupo controle foi de 22,1 anos (p=0,99). O intervalo de tempo a lesão e a cirurgia foi, em média, cinco meses. No pré-operatório, o VO2max, em mL/kg/min, foi em média ? desvio padrão de 45,2 +- 4,3, aos seis meses de pós-operatório 48,9 +- 3,8 (p < 0,001) e no grupo controle 56,9 +- 4,2 (p < 0,001 comparado ao pré-operatório e pós-operatório). A porcentagem de gordura corporal, em média +- desvio padrão, no pré-operatório foi de 14,7+- 3,7, no pós-operatório 14,9 +- 5,4 e no grupo controle 12,8 +- 4, sem diferença estatisticamente significativa entre os grupos. Os resultados do questionário Lysholm no pré-operatório, pós-operatório e no grupo controle foram, em média, 77,25, 94,12 e 97,5 (p < 0,05 em todas as comparações) e do questionário IKDC subjetivo foram 59,46, 87,75 e 97,28 (p < 0,001 em todas as comparações). O déficit de pico de torque de extensão do joelho a 60 O/s, foi de 21,5% no pré-operatório, 15,7% no pós-operatório (p=0,63) e 3,1% no grupo controle (p < 0,001 com relação ao pré-operatório e pós-operatório). CONCLUSÃO: Os jogadores profissionais de futebol de campo avaliados seis meses após a reconstrução do LCA apresentaram VO2max significativamente inferior aos resultados do grupo controle, embora os resultados pós-operatórios tenham sido significativamente superiores aos observados no pré-operatório. Houve uma melhora significativa nos scores de função do joelho no pós-operatório com relação ao pré-operatório e a composição corporal dos indivíduos não apresentou diferenças estatisticamente significativas / INTRODUCTION: Anterior cruciate ligament (ACL) injury is a severe injury and may impact a professional football player\'s career. Surgical treatment is often indicated due to knee instability. Although ACL reconstruction (ACLR) is considered a successful procedure in restoring knee stability in athletes, it has been shown that only 55% return to competitive sports after surgery. Professional football players need technical, tactical and physical skills to succeed, including adequate knee function and aerobic capacity. Our purpose is to evaluate aerobic capacity in professional football players with ACL injury and six months after ACL reconstruction. METHODS: Twenty professional football players underwent ACL reconstruction with autologous hamstring grafts and were compared to 20 active, uninjured professional football players. We assessed maximal aerobic capacity with maximal oxygen consumption (VO2max) and submaximal with ventilatory thresholds, measured by ergoespirometric test performed in a treadmill with a modified Heck protocol. The tests were performed pre-operatively and six months after ACLR, and compared to the control group. We also performed knee function questionnaires (Lysholm and IKDC), isokinetic strength test and body composition evaluation with electric bioimpedance. RESULTS: ACL group average age was 21.7 y.o., and control group 22.1 y.o.(p=.99). Time span between injury and surgery was 5 months, in average. Pre-operative VO2max was 45.2 +- 4.3 mL/kg/min, post-operative was 48.9 +- 3.8 (p > .001) and control group was 56.9 +- 4.2 (p < 001 in both comparisons). Pre-op body fat percentage was 14.7+-3.7, post-op was 14.9 +- 5.4 and control 12.8 +- 4 (n.s.). Lysholm questionnaire results were 77.25, 94.12, and 97.5 (pre-op, post-op and control, respectively, p <. 05 in all comparisons). IKDC results were 59.46, 87.75 and 97.28 (pre-op, post-op and control, respectively, p < .001 in all comparisons). Preop peak torque isokinetic knee extension deficit at 60°/s was 21.5%, postop 15.7% (p=.63) and control 3.1% (p <. 001). CONCLUSION: Professional football players had significantly lower VO2max six months after ACLR compared to controls, although their results were significantly higher than observed pre-operatively. There was a significant improvement in knee function scores after ACLR. Body composition evaluation was not significant different among the groups evaluated

OBJETIVO: Avaliar o padrão de degeneração histológica do ligamento cruzado posterior (LCP) em pacientes com artrose submetidos à artroplastia total de joelho com prótese com substituição do ligamento cruzado posterior (LCP). A degeneração histológica foi classificada em leve, moderada e grave. Os achados histológicos foram correlacionados com dados clínicos, radiográficos e do transoperatório (presença ou ausência do ligamento cruzado anterior) com a finalidade de aferir se estes parâmetros seriam capazes de predizer o grau de degeneração histológica do LCP em pacientes com gonartrose. MÉTODOS: foram avaliados 89 ligamentos cruzados posterior de 85 pacientes com idade média de 69,79 anos, sendo 69 do sexo feminino, 16 do masculino. O LCP foi corado em hematoxilina-eosina e Tricrômio de Gomori e classificado quanto ao comprometimento histológico em leve, moderado e grave. A degeneração histológica foi correlacionada aos parâmetros idade, artrose radiográfica classificada por Ahlbäck (grau I ao V), eixo radiográfico tíbio-femoral (varo, neutro e valgo), e estado do ligamento cruzado anterior (LCA), presença ou ausência.Os achados histológicos de hipercelularidade, infiltração linfocitária crônica, proliferação vascular; presença de cistos; clones de condrócitos; degenerações colágena, fibrinóide, cartilaginosa ,gordurosa e mucoide foram correlacionados com o grau de degeneração do LCP e ao estado de conservação do LCA. RESULTADO: Não foram identificadas relações entre o grau de degeneração histológica do LCP e faixa etária (abaixo ou acima de 70 anos), sexo, classificação radiográfica de Ahlbäck e presença ou ausência do LCA. Os achados histológicos de degeneração fibrinóide, proliferação vascular e presença de cistos estiveram estatisticamente relacionados à degeneração histológica grave do LCP. CONCLUSÃO: Os parâmetros clínicos e radiográficos não foram capazes de predizer o grau de degeneração histológica do LCP .Os achados histológicos de degeneração fibrinóide, proliferação vascular e presença de cistos caracterizaram a degeneração histológica grave do LCP / OBJECTIVE: Evaluate the histologic degeneration pattern of the posterior cruciate ligament (PCL) in osteoarthrosis patients submitted to total knee replacement with a cruciate substituting prosthesis. The histologic degeneration was classified in mild, moderate and severe. The histologic pattern was related to clinical, per-operatory (presence or absence of anterior cruciate ligament) and radiographic parameters with the aim to settle if these parameters would be reliable to predict the PCL degeneration grade. METHODS: 89 PCLs from 85 patients, 16 men, 69 women, mean age 69, 79 years old. PCL was stained with hematoxylin and eosin and trichromium of Gomori. The PCL histologic degeneration was graded from normal-minimum to severe. The histologic PCL degeneration pattern was related to age, radiographic arthrosis classification (Ahlbäck - grades I to V), knee radiographic axis (varus, neutral, valgus) and to the ACL status (presence or absence).The histologic findings of hipercellularity, chronic lymphocit infiltration, neoangiogenesis, cysts, collagen degeneration (deg), fibrinoid deg, mucoid deg., cartilaginous, deg., fat deg. and condrocyte clones were related to the grade of PCL degeneration and to ACL status. RESULTS: There was no correlation of histologic degeneration to sex or age (above or below 70 years), arthrosis radiographic classification (Ahlbäck) and presence or absence of ACL. The histological findings of fibrinoid degeneration, vascular proliferation and cysts were statistically related to severe histologic LCP degeneration. CONCLUSION: The parameters studied were not capable of predicting the grade of LCP degeneration. The histological findings of fibrinoid degeneration, vascular proliferation and cysts were characteristic of severe PCL histologic degeneration

INTRODUÇÃO: A localização ideal dos túneis do enxerto para a reconstrução do ligamento cruzado anterior (LCA) está na área da impressão original do ligamento. Entretanto, há pacientes que mesmo após a reconstrução anatômica do LCA se queixam de falseio. O objetivo do presente estudo foi comparar a estabilidade do joelho com túneis em duas posições diferentes da área de impressão original do LCA. MÉTODOS: Trinta reconstruções anatômicas do LCA foram realizadas em 15 joelhos de cadáver, com preservação do quadril até o tornozelo. Não foram criadas lesões para intensificar a instabilidade do joelho. O protocolo possuía quatro grupos: (1) LCA intacto, (2) deficiência completa e isolada do LCA, (3) reconstrução do LCA na posição anteromedial (AM REC) e (4) central (C REC) da impressão original do ligamento (ordem randômica). A estabilidade do joelho foi testada pelo teste de Lachman (68 N) e pelo teste do \"pivot shift\" mecanizado (CPM de 0° a 55° + valgo e rotação interna de 20 Nm) e avaliada por sistema óptico de navegação e tomografia 3D. A descrição da cinemática do joelho com 6 graus de liberdade foi realizada por sistema de coordenadas com eixo no centro geométrico dos côndilos. Estatística: rotação interna (°) e translação anterior (mm) foram avaliados nos testes do \"pivot shift\" e Lachman com 2 e 1- way RM ANOVA, respectivamente (alfa < 0,05). RESULTADOS: O grupo C REC em comparação com o grupo AM REC apresentou menor rotação interna nos testes do \"pivot shift\" (0,6° ± 0,3° vs. 1,8° ± 0,3°, respectivamente, P < 0,05) e de Lachman (2,9° ± 0,4° vs. 3,9° ± 0,4°, respectivamente, P < 0,05) e não apresentou diferença com relação à translação anterior nos mesmos testes do \"pivot shift\" (4,7 mm ± 0,4 mm vs. 4,5 mm ± 0,4 mm, respectivamente, P > 0,05) e de Lachman (1,2 mm ± 0,2 mm vs. 1,1 mm ± 0,2 mm, respectivamente, P > 0,05). Os grupos C REC e AM REC não mostraram diferença quando comparados ao grupo LCA intacto no teste de Lachman para translação anterior (2,1 mm ± 0,5 mm) e rotação interna (3,0° ± 0,5°) (para ambos, P > 0,05) e mostraram diferença no teste do \"pivot shift\" (6,4 mm ± 0,4 mm e 5,6° ± 0,3°, respectivamente, P < 0.05). DISCUSSÃO: Este foi o primeiro estudo a demonstrar alterações da cinemática do joelho em cadáveres com todo o membro preservado e sem lesões associadas para aumentar a instabilidade do joelho, na sequência completa dos experimentos (LCA intacto, lesionado e após as reconstruções anatômicas) com o aparelho de \"pivot shift\" mecanizado. CONCLUSÃO: A reconstrução anatômica do LCA na posição central permitiu uma maior restrição da rotação interna do joelho, em comparação à reconstrução anatômica anteromedial, quando submetida aos testes do \"pivot shift\" mecanizado e de Lachman. Tanto a AM REC quanto a C REC permitiram restabelecer a translação anterior do joelho próximo àquela função do LCA original / INTRODUCTION: The optimal femoral and tibial tunnel locations for grafting in anterior cruciate ligament (ACL) reconstruction are within the original ACL footprint. However, even with anatomic reconstructions, some patients still report giving way. This study aimed to compare knee stability in two different anatomic footprint ACL reconstruction positions. METHODS: Thirty anatomic ACL reconstructions were performed in 15 cadaveric hip-totoe specimens. No associated lesions were created to intensify knee instability. The protocol was conducted in four groups: (1) intact ACL, (2) complete-isolated ACL deficiency, (3) anatomic femoral and tibial anteromedial ACL reconstruction (AM REC); and (4) anatomic femoral and tibial central ACL reconstruction (Central REC). The reconstructions were randomly assigned. The Lachman test (68 N) and mechanized pivot-shift test (CPM from 0° to 55° + valgus and internal torque of 20 Nm) were recorded with optical tracking system and 3D tomography. The 6 degrees of freedom knee kinematics was described with geometric condyle axis based coordinate system. Statistics: internal rotation (°) and anterior displacement (mm) were analyzed in both tests with two- and one-way RM ANOVA (alfa < 0,05). RESULTS: The Central REC group compared to the AM REC group showed a smaller degree of internal rotation in the pivot-shift (0,6° ± 0,3° vs. 1,8° ± 0,3°, respectively, P < 0,05) and Lachman (2,9° ± 0,4° vs. 3,9° ± 0,4°, respectively, P < 0,05) tests and no difference in anterior translation in either the pivot-shift (4,7 mm ± 0,4 mm vs. 4,5 mm ± 0,4 mm, respectively, P > 0,05) or Lachman (1,2 mm ± 0,2 mm vs. 1,1 mm ± 0,2 mm, respectively, P > 0,05) test. Central REC and AM REC groups showed no differences compared to intact ACL group in Lachman test for anterior translation (2,1 mm ± 0,5 mm) and internal rotation (3,0° ± 0,5°) (for both, P > 0,05) but did show significant differences in the pivot-shift test (6,4 mm ± 0,4 mm and 5,6° ± 0,3°, respectively, P < 0.05). DISCUSSION: This was the first study to demonstrate knee kinematic changes in a hip-to-toe cadaver model without associated lesions to amplify knee instability with a mechanized pivot shift in the complete sequence of intact, ACL-deficient and anatomic reconstructions. CONCLUSION: Central anatomic ACL reconstruction permitted greater restriction of internal rotation than did anteromedial anatomic ACL reconstruction based on mechanized pivot shift and Lachman tests. Either AM REC and C REC restored anterior translation close to original ACL function