Sandra Umeda Sasaki

Anterior cruciate ligament reconstruction with double bundle versus single bundle: experimental study

OBJECTIVE To test an intra-articular reconstruction of the anterior cruciate ligament of the knee in 10 human cadavers by replacing 2 anterior cruciate ligament bundles, with the purpose of producing a surrogate that would be structurally more similar to the anatomy of the anterior cruciate ligament and would provide the knee with more stability. METHODS We reconstructed the anteromedial and posterolateral bundles using a quadriceps muscle tendon graft that included a patellar bone segment. The anteromedial bundle was replaced in 10 knees (5 right and 5 left knees from different cadavers) by a quadriceps-bone tendon graft, and the anteromedial and posterolateral bundles were replaced in the matching pairs of these knees. In the latter, the bone segment was fixed to the tibia, and the tendinous portion of the graft was divided longitudinally creating two 5-mm wide bundles that were inserted individually into the femur through 2 independent bone tunnels. Then, the knees were tested mechanically to evaluate the tibial anterior dislocation in relation to the femur, as well as the rigidity of the graft. The control group was formed by the knees with intact anterior cruciate ligaments, before being resected to be reconstructed. RESULTS The results obtained did not show superiority of double-bundle reconstruction over single-bundle reconstruction, and neither technique provided the knee with the same stability and rigidity of the intact anterior cruciate ligament. CONCLUSION Our hypothesis, based on the anatomy and biomechanics of the knee, that reconstruction of the anterior cruciate ligament using 2 bundles would result in a more anatomic reconstruction and provide better containment of the anterior tibial translation was not supported by the results of this study.

Comparative study on anterior cruciate ligament reconstruction: determination of isometric points with and without navigation

OBJECTIVES: To compare the accuracy of tunnel placement and graft isometry for anterior cruciate ligament reconstruction performed using a computer-assisted navigation system (Orthopilot) and using traditional instruments. METHODS: The anterior cruciate ligament was removed intact from 36 pairs of human cadaver knees. From each pair, one knee was randomized to Group 1 (conventional) and the other to Group 2 (Orthopilot). An inelastic suture was then passed through the central points of the tibial and femoral tunnels. Neither of the tunnels was drilled. All knees were then dissected, and six parameters were obtained: distances from the tibial tunnel center to the 1) posterior cruciate ligament, 2) anterior horn of the lateral meniscus and 3) medial tibial spine; 4) distance from the femoral tunnel center to the posterior femoral cortex; 5) femoral tunnel coronal angle; and 6) variation of the distance from the femoral to the tibial tunnel with the knee extended and at 90 degrees of flexion. RESULTS: The variation of the distance from the femoral to the tibial tunnel during flexion and extension was smaller in the Orthopilot group (better isometry) compared to the conventional group. There were no statistical differences in any other parameters between the groups, and all tunnels were considered to be in satisfactory positions. DISCUSSION: The results obtained for anterior cruciate ligament reconstruction depend on precise isometric point positioning, and a navigation system is a precision tool that can assist surgeons in tunnel positioning. CONCLUSION: No differences in tunnel position were observed between the groups. Nonetheless, better isometry was achieved in the Orthopilot group than with conventional instruments.

An in vitro biomechanical comparison of anterior cruciate ligament reconstruction: single bundle versus anatomical double bundle techniques

INTRODUCTION Anterior cruciate ligament ruptures are frequent, especially in sports. Surgical reconstruction with autologous grafts is widely employed in the international literature. Controversies remain with respect to technique variations as continuous research for improvement takes place. One of these variations is the anatomical double bundle technique, which is performed instead of the conventional single bundle technique. More recently, there has been a tendency towards positioning the two bundles through double bone tunnels in the femur and tibia (anatomical reconstruction). OBJECTIVES To compare, through biomechanical tests, the practice of anatomical double bundle anterior cruciate ligament reconstruction with a patellar graft to conventional single bundle reconstruction with the same amount of patellar graft in a paired experimental cadaver study. METHODS Nine pairs of male cadaver knees ranging in age from 44 to 63 years were randomized into two groups: group A (single bundle) and group B (anatomical reconstruction). Each knee was biomechanically tested under three conditions: intact anterior cruciate ligament, reconstructed anterior cruciate ligament, and injured anterior cruciate ligament. Maximum anterior dislocation, rigidity, and passive internal tibia rotation were recorded with knees submitted to a 100 N horizontal anterior dislocation force applied to the tibia with the knees at 30, 60 and 90 degrees of flexion. RESULTS There were no differences between the two techniques for any of the measurements by ANOVA tests. CONCLUSION The technique of anatomical double bundle reconstruction of the anterior cruciate ligament with bone-patellar tendon-bone graft has a similar biomechanical behavior with regard to anterior tibial dislocation, rigidity, and passive internal tibial rotation.

O tratamento cirúrgico é imperativo na lesão do ligamento cruzado anterior? Há lugar para o tratamento conservador?

The purpose of this paper is to answer the questions made in the title of the paper. Surgical indication for the treatment of anterior cruciate ligament (ACL) lesion has been a consensus since 1980, and today the widespread use of the arthroscopic technique is a reality, even in academic circles. For this reason, the therapy indicated to treat the most common ligament lesion of the knee ACL lesion has been the isolated reconstruction of the ligament, and the condition was no longer considered within the context of instabilities resulting from rotational trauma. A review of the literature dealing with ACL lesion treatment was carried out: historical papers, papers published in the Revista Brasileira de Ortopedia in the last seven years, and 13 papers from the international literature selected based on the quality of their method. A cohort study in the ACL reconstruction series of the authors was also included in the review. In most of the Brazilian papers reviewed, indication of surgical treatment is peremptory, and the clinical verification of the lesion, whether acute or chronic, is made just by the positive results of anterior drawer, Lachman, and jerk tests, or the pivot shift, without evaluating peripheral ligaments, the type of instability, and the quantification of components; in the 13 international papers, the authors observed that conservative ACL treatment is an option to be considered, in particular in view of the results presented by patients so treated. In their own series, the authors found that among patients operated on, a significant number of knees (55), corresponding to 6.2% of the total, presented a new lesion before the second year, and those were exactly the cases that had been operated on just for the ACL, in spite the positive, moderate magnitude results in rotational instability tests. A statement can be made that it is possible to treat an ACL lesion with conservative methods, and therefore surgical treatment is not mandatory, and, further, that when indicated, surgery must be planned considering the degree of ligament looseness resulting from the peripheral ligaments.

BILATERAL LOCALIZED PIGMENTED VILLONODULAR SYNOVITIS OF THE KNEE: CASE REPORT AND REVIEW

ABSTRACT Objectives Several cases of bilateral diffuse pigmented villonodular synovitis (PVNS) or tenosynovial giant cell tumor have been described in the literature. Nevertheless, some presentations are rare and differential diagnoses are necessary. Methods The purpose of this study was to perform a systematic review of the literature related to PVNS and to report a rare supra-patellar bilateral and focal presentation. We performed a systematic data review in the Pubmed Clinical Queries database using MeSH and keywords related to PVNS and tenosynovial giant cell tumor. Results Two cases of bilateral and local PVNS had been previously described, but neither was localized in the supra-patellar compartment. To our knowledge, this case report is the first to describe supra-patellar bilateral and localized PVNS of the knee. This case involves a 28 -year-old woman with bilateral localized PVNS of the supra-patellar recess of the knee. MRI showed a low-signal intensity nodule in T1- and T2-weighted images. These were associated with hemosiderin pigmentation. Conclusion The most important finding of the case reported is related to rarity and location. Histopathology analysis confirmed a rare case of hemosiderin pigmentation in the capsular nodule with internal non-pigmented villous content. Lipoma arborescens in the supra-patellar form must be ruled out as a differential diagnosis since it occurs in the same site. Level of Evidence IV; Case series.

Tratamento cirúrgico da tendinite distal da patela

A tendinite distal da patela e uma doenca que acomete principalmente jovens esportistas e caracteriza-se por dor referida na extremidade distal da patela junto a insercao do ligamento patelar. O tratamento inicial preconizado e sempre conservador com fisioterapia. A grande maioria tem boa resposta a este tipo de conduta, mas em alguns raros casos os sintomas nao regridem exigindo uma mudanca de conduta. Para este grupo usamos o tratamento cirurgico com tecnica derivada de Trillat que se baseia na utilizacao de um enxerto de parte do tendao do musculo Gracil implantado dentro do ligamento patelar, inserido intra-osseo na patela e fixado na tuberosidade anterior da tibia. Foram operados seis pacientes, sendo que em dois casos a operacao foi bilateral, totalizando oito joelhos. O seguimento minimo foi de tres anos, com avaliacao final dentro do indice considerado como EXCELENTE, conforme a cotacao ARPEGE, para todos os joelhos.