INTRAOPERATIVE CLINICAL TEST FOR KINEMATIC ASSESSMENT OF ACl GRAFT BEHAVIOUR WITH COMPUTER ASSISTED PROCEDURE

This paper describes a protocol for an accurate and extensive computer-assisted in vivo evaluation of joint laxities durinQl reconstructions of anterior cruciate ,ligament (ACL). The operating technique is a double bundle with over the top graft. Kinematic tests are performed, intraoperatively, before the ACL reconstruction, with ACL deficient knees, and after the ACL reconstruction. Results of first four in vivo cases, highlight that the reconstruction gives a complete restore of stability, in the antero-posterior direction, at 30° and 90° degrees giving and increased stability up to 73%, confirming the role of the ACL in the control of AP dislocation. Internal and external rotations were also satisfactorily restored after the graft fixation; in particular at 30° of tlexion, the reconstruction gives a good control of the joint, reducing laxity up to 43%

Fully human IgG and IgM antibodies directed against the carcinoembryonic antigen (CEA) Gold 4 epitope and designed for radioimmunotherapy (RIT) of colorectal cancers

BACKGROUND: Human monoclonal antibodies (MAbs) are needed for colon cancer radioimmunotherapy (RIT) to allow for repeated injections. Carcinoembryonic antigen (CEA) being the reference antigen for immunotargeting of these tumors, we developed human anti-CEA MAbs. METHODS: XenoMouse(®)-G2 animals were immunized with CEA. Among all the antibodies produced, two of them, VG-IgG2κ and VG-IgM, were selected for characterization in vitro in comparison with the human-mouse chimeric anti-CEA MAb X4 using flow cytometry, surface plasmon resonance, and binding to radiolabeled soluble CEA and in vivo in human colon carcinoma LS174T bearing nude mice. RESULTS: Flow cytometry analysis demonstrated binding of MAbs on CEA-expressing cells without any binding on NCA-expressing human granulocytes. In a competitive binding assay using five reference MAbs, directed against the five Gold CEA epitopes, VG-IgG2κ and VG-IgM were shown to be directed against the Gold 4 epitope. The affinities of purified VG-IgG2κ and VG-IgM were determined to be 0.19 ± 0.06 × 10(8 )M(-1 )and 1.30 ± 0.06 × 10(8 )M(-1), respectively, as compared with 0.61 ± 0.05 × 10(8 )M(-1 )for the reference MAb X4. In a soluble phase assay, the binding capacities of VG-IgG2κ and VG-IgM to soluble CEA were clearly lower than that of the control chimeric MAb X4. A human MAb concentration of about 10(-7 )M was needed to precipitate approximatively 1 ng (125)I-rhCEA as compared with 10(-9 )M for MAb X4, suggesting a preferential binding of the human MAbs to solid phase CEA. In vivo, 24 h post-injection, (125)I-VG-IgG2κ demonstrated a high tumor uptake (25.4 ± 7.3%ID/g), close to that of (131)I-X4 (21.7 ± 7.2%ID/g). At 72 h post-injection, (125)I-VG-IgG2κ was still concentrated in the tumor (28.4 ± 11.0%ID/g) whereas the tumor concentration of (131)I-X4 was significantly reduced (12.5 ± 4.8%ID/g). At no time after injection was there any accumulation of the radiolabeled MAbs in normal tissues. A pertinent analysis of VG-IgM biodistribution was not possible in this mouse model in which IgM displays a very short half-life due to poly-Ig receptor expression in the liver. CONCLUSION: Our human anti-CEA IgG2κ is a promising candidate for radioimmunotherapy in intact form, as F(ab')(2 )fragments, or as a bispecific antibody

New intraoperative protocol for kinematic evaluation of ACL reconstruction: Preliminary results

A real improvement in anterior cruciate ligament (ACL) surgery would be achieved if a global kinematic evaluation of graft performance could be made during surgery. A quantitative evaluation of all residual instabilities would be helpful in the evaluation of graft performances. This paper describes a new protocol for an accurate and extensive computer-assisted in vivo evaluation of joint laxities during ACL reconstruction. Fifteen in vivo kinematic evaluations during ACL reconstruction were performed using an optical localizer and custom software. The capability of the protocol was studied by analyzing the accuracy and repeatability of the results, the ergonomics of the setup, time taken, interactions with the surgical steps, and efficacy of the acquisitions. Repeatability of the tests, at maximum force, remained under 1 mm/2 degrees . Repeatability in tibia position and orientation was lower than 1 mm/4 degrees . Secondary laxities during stress tests remained under 2 mm/3 degrees . Added time to surgery was about 11 min. ACL graft increased joint stability up to 52% with respect to the preoperative level. The simplicity and morbidity of the test procedure and system was minimally invasive and allowed a quantitative evaluation of knee laxities at time zero. The repeatability of the tests opens the way for future research on in vivo evaluation of different ACL reconstruction techniques, which may lead to a better understanding of associated lesions and their role to the global knee stability

Kinematic analysis of two different tunnel orientations in double-bundle ACL reconstruction

none6noneS. Zaffagnini; S. Martelli; S. Bignozzi; N. Imakiire; D. Bruni; M. MarcacciS. Zaffagnini; S. Martelli; S. Bignozzi; N. Imakiire; D. Bruni; M. Marcacc