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Cruciate Ligament Reconstruction (cruciate + ligament_reconstruction)
Selected AbstractsBiomechanical effects of medial,lateral tibial tunnel placement in posterior cruciate ligament reconstructionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2003Keith L. Markolf With most posterior cruciate (PCL) reconstruction techniques, the distal end of the graft is fixed within a tibial bone tunnel. Although a surgical goal is to locate this tunnel at the center of the PCL's tibial footprint, errors in medial,lateral tunnel placement of the tibial drill guide are possible because the position of the tip of the guide relative to the PCL's tibial footprint can be difficult to visualize from the standard arthroscopy portals. This study was designed to measure changes in knee laxity and graft forces resulting from mal-position of the tibial tunnel medial and lateral to the center of the PCL's tibial insertion. Bone,patellar tendon,bone allografts were inserted into three separate tibial tunnels drilled into each of 10 fresh-frozen knee specimens. Drilling the tibial tunnel 5 mm medial or lateral to the center of the PCL's tibial footprint had no significant effect on knee laxities: the graft pretension necessary to restore normal laxity at 90° of knee flexion (laxity match pretension) with the medial tunnel was 13.8 N (29%) greater than with the central tunnel. During passive knee flexion,extension, graft forces with the medial tibial tunnel were significantly higher than those with the central tunnel for flexion angles greater than 65° while graft forces with the central tibial tunnel were not significantly different than those with the lateral tibial tunnel. Graft forces with medial and lateral tunnels were not significantly different from those with a central tunnel for 100 N applied posterior tibial force, 5 N m applied varus and valgus moment, and 5 N m applied internal and external tibial torque. With the exception of slightly higher graft forces recorded with the medial tunnel beyond 65° of passive knee flexion, errors in medial,lateral placement of the tibial tunnel would not appear to have important effects on the biomechanical characteristics of the reconstructed knee. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] The effects of graft width and graft laxity on the outcome of caprine anterior cruciate ligament reconstructionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2002J. F. Cummings We studied how initial graft size and initial graft laxity affected the biomechanics of anterior cruciate ligament (ACL) reconstruction at six months. Sixteen goats had bilateral reconstructions staged eight weeks apart. Autografts 4 and 7 mm wide were taken from the central patellar tendon (PT). Lax grafts were created by adding 4 mm slack to the graft before fixing. We reconstructed each joint using a combination of width and laxity treatments. Both factors were changed for the contralateral joint and all combinations appeared with equal frequency. At six months we measured the joint extension limit, anterior,posterior (AP) translation, and osteoarthritic changes. The grafts were then tested to failure to determine their mechanical properties. After six months the difference in initial treatments had disappeared: there was no difference in graft cross-section due to the different initial widths and there was no difference in joint AP translation due to the initial graft laxity. We did observe that wide grafts were associated with a block to extension, decreased joint AP translation, and increased articular cartilage damage and osteophyte formation. While AP translation was reduced, it was correlated with decreased extension, possibly indicating an increase in scar tissue formation rather than a more functional graft. Neither graft width nor graft laxity produced differences in any graft mechanical properties. This suggests that the use of larger grafts to prevent increased AP translation has undesirable complications. Ultimately, we conclude that neither of these surgical treatments strongly affects the biomechanical result of caprine ACL reconstruction. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Single-bundle posterior cruciate ligament reconstruction with remnant preservation: lateral versus medial-sided augmentation techniqueORTHOPAEDIC SURGERY, Issue 1 2009Jin-zhong Zhao MD Objective:, To compare the results of lateral versus medial-sided augmentation techniques in single-bundle posterior cruciate ligament (PCL) reconstruction with remnant preservation. Methods:, Forty-two cases of isolated chronic PCL ruptures were reconstructed in a single-bundle manner with remnant preservation. The patients were randomly separated into two groups: in the medial-sided augmentation (MSA) group the graft passed through the medial side of the remnant and in the lateral-sided augmentation (LSA) group it passed through the lateral side. Results:, Nineteen patients in the MSA group and 17 in the LSA group were followed up for a minimum of 2 years. At the final follow-up, the average side-to-side differences in posterior laxity were 1.6 ± 1.2 mm and 1.5 ± 1.3 mm respectively in the MSA and LSA groups. According to the International Knee Documentation Committee (IKDC) scale, patient numbers graded as normal, nearly normal and abnormal were 14 (73.7%), 4 (21.1%), and 1 (5.3%) in the MSA group, and 13 (76.5%), 3 (17.6%), and 1 (5.9%) in the LSA group. The IKDC subjective scores were 93.1 ± 3.8 and 92.6 ± 4.1, the Lysholm scores were 95.0 ± 4.6 and 93.7 ± 4.2, and the Tegner scores were 5.4 ± 0.9 and 5.6 ± 0.7 respectively in the MSA and LSA groups. Statistical analysis showed no significant differences between the MSA and the LSA group regarding all subjective and objective results. Conclusion:, In single-bundle PCL reconstruction with remnant preservation, similar subjective and objective results can be obtained with MSA and LSA techniques. [source] Does intraarticular morphine improve pain control with femoral nerve block after anterior cruciate ligament reconstruction? (Vanderbilt University Medical Center, Nashville, TN) American Journal of Sports Medicine 2001;29:327,332.PAIN PRACTICE, Issue 4 2001Eric C. McCarthy In a prospective, randomized, double-blinded manner, the authors of this study compared the effects of a preoperative intraarticular injection of morphine (5 mg) or a placebo, combined with a postoperative femoral nerve block, on postoperative pain. Sixty-two patients underwent an arthroscopically assisted anterior cruciate ligament reconstruction using patellar tendon autograft under general anesthesia. No statistical difference between the 2 groups was evident in terms of age, sex, weight, operative time, volume of bupivacaine received with the femoral nerve block, or tourniquet use or tourniquet time. A comparison of the visual analog pain scale scores revealed no statistical difference between the groups at any point after the operation. Both groups had a significant decrease in visual analog scale scores after the femoral nerve block. No significant difference in postoperative narcotic medication use was evident in the recovery room or at home. A post hoc analysis revealed that the study power reached 87% with a significance level of 5%. Conclude that the postoperative femoral nerve block was effective and intraarticular morphine provided no additional benefit. Comment by Alan David Kaye, M.D., Ph.D., and Erin Bayer, M.D. This prospective, randomized, double blinded study compared the effects of preoperative intraarticular injection of morphine or a placebo along with postoperative femoral "three-in-one" block on postoperative pain. 62 patients underwent arthroscopic ACL reconstruction under general anesthesia. After induction of anesthesia, patients were injected with either morphine 5 mg or placebo along with local anesthetics intraarticularly. Femoral nerve blocks were performed in the recovery room with a total of 3 mg/kg bupivacaine. The VAS of pain was assessed immediately postoperatively and at six time points afterward up to 24 hours. This study concluded that there were no statistical differences between the two groups comparing VAS. Also no significant difference was observed in postoperative narcotic use in the recovery room or at home. The study included antiemetics; however, the results did not include if the morphine group had a larger incidence of nausea or vomiting postoperatively. Finally, the authors suggest that there are no advantages to use of intraarticular morphine with a femoral nerve block post-operatively. A future study employing preoperative femoral nerve block with or without use of intraarticular morphine might be interesting to see on arthroscopic ACL repairs to obtain adequate analgesia as the authors suggested. [source] Prospective randomized comparison of endobutton versus cross-pin femoral fixation in hamstring anterior cruciate ligament reconstruction with 2-year follow-upANZ JOURNAL OF SURGERY, Issue 3 2010Rohan Price Abstract Background:, To determine if there is a different clinical outcome after TransFix versus endobutton femoral fixation in hamstring anterior cruciate ligament (ACL) reconstruction. Methods:, Twenty-nine patients were randomized into either Endobutton (Smith & Nephew, Andover, MA, USA) (n= 13) or TransFix (Arthrex, Naples, FL, USA) (n= 16) femoral fixation in hamstring ACL reconstruction. The distal fixation was with a bioabsorbable interference screw. The evaluation methods were clinical history and examination, KT1000 arthrometry for laxity as well as the International Knee Documentation Committee (IKDC) scores over a 2-year time frame. Results:, There were no significant differences between the study groups preoperatively. For the 2-year follow-up, 11 patients in the Endobutton group and 13 patients in the TransFix group were available (greater than 80%). No statistical differences between the two groups were found at the 1- or 2-year follow-up examinations. At the 2-year follow-up, 72.7% of the Endobutton and 84.6% of the TransFix group patients were in the IKDC A or B categories. Additional procedures postoperatively occurred more frequently in the TransFix group. Conclusions:, There were no significant differences in the results for either technique of femoral fixation. Level of Evidence:, Level I. [source] Cyclical ischaemic preconditioning modulates the adaptive immune response in human limb ischaemia,reperfusion injuryBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 4 2009P. J. Sullivan Background: Reperfusion injury (RI) has significant local and systemic consequences. Ischaemic preconditioning (IPC) modulates RI and the innate immune response. This study examined whether IPC attenuates RI-mediated changes in lymphocyte populations and function following elective surgery. Methods: Twenty-five patients sustaining 1 h of tourniquet ischaemia during cruciate ligament reconstruction were randomized before surgery to three 5-min ischaemia cycles separated by 5 min of reperfusion, or to a control group. Systemic levels of interleukin (IL) 4 and interferon (IFN) ,, and surface expression of CD45ro/ra, CD62L and CD95 were measured. T cells were examined systemically and in stimulated serum co-culture to determine CD4/CD8 and Th1/Th2 shifts through intracellular cytokine production. Results: CD4 CD45ro cell numbers increased after RI without IPC, whereas CD8 cells expressing CD45ro and CD95 increased with IPC. Preconditioned serum in co-culture attenuated increases in CD4 and decreases in CD8 numbers, a process prevented by inhibition of antigen activation. Following RI, systemic IL-2 levels were significantly lower after IPC, whereas co-culture with post-RI serum increased proinflammatory intracellular cytokine production. Conclusion: IPC modulated T cell responses in limb RI through reduced activation and proinflammatory cytokine production by CD4 cells, while preventing CD4/CD8 derangement. IPC prevented lymphocyte-directed immune dysfunction. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] The arterial supply of the patellar tendon: Anatomical study with clinical implications for knee surgeryCLINICAL ANATOMY, Issue 3 2009Jack Pang Abstract The middle-third of the patellar tendon (PT) is well-established as a potential graft for cruciate ligament reconstruction, but there is little anatomical basis for its use. Although studies on PT vascular anatomy have focused on the risk to tendon pedicles from surgical approaches and knee pathophysiology, the significance of its blood supply to grafting has not been adequately explored previously. This investigation explores both the intrinsic and extrinsic arterial anatomy of the PT, as relevant to the PT graft. Ten fresh cadaveric lower limbs underwent angiographic injection of the common femoral artery with radio-opaque lead oxide. Each tendon was carefully dissected, underwent plain radiography and subsequently schematically reconstructed. The PT demonstrated a well-developed and consistent vascularity from three main sources: antero-proximally, mainly by the inferior-lateral genicular artery; antero-distally via a choke-anastomotic arch between the anterior tibial recurrent and inferior medial genicular arteries; and posteriorly via the retro-patellar anastomotic arch in Hoffa's fat pad. Two patterns of pedicles formed this arch: inferior-lateral and descending genicular arteries (Type-I); superior-lateral, inferior-lateral, and superior-medial genicular arteries (Type-II). Both types supplied the posterior PT, with the majority of vessels descending to its middle-third. The middle-third PT has a richer intrinsic vascularity, which may enhance its ingrowth as a graft, and supports its conventional use in cruciate ligament reconstruction. The pedicles supplying the PT are endangered during procedures where Hoffa's fat pad is removed including certain techniques of PT harvest and total knee arthroplasty. Clin. Anat. 22:371,376, 2009. © 2009 Wiley-Liss, Inc. [source] One- and two-strand posterior cruciate ligament reconstructions: Cyclic fatigue testingJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2005Jason T. Shearn This study examined how one- and two-strand posterior cruciate ligament (PCL) reconstructions resist the return of posterior translation during repetitive knee cycling. The femoral attachment of the one-strand graft and the anterior strand of the two-strand (AD2) grafts were located within the anterior one-third of the femoral PCL footprint. The second strand was placed within the middle third of the femoral footprint in one of three locations: middle,distal (MD), middle,middle (MM), or middle,proximal (MP). During repetitive knee cycling from 5° to 120° flexion with a 100 N posterior force, the intact knee had less than 1 mm of residual posterior translation after 2048 flexion,extension cycles. Under similar cyclic conditions, the AD2 -MM reconstruction achieved the most cycles before failure; however, this two-strand configuration failed in less than 700 cycles. The other reconstructions, either one strand or two strand, failed in less than 350 cycles. The surface failure location for 19 of 25 graft strands was within the femoral one-third of the strand. We concluded that one- and two-strand reconstructions under moderate loading and a range of motion from 5° to 120° flexion have an unacceptably high cyclic failure rate suggesting modifications of the allowable postoperative knee flexion and loading. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] | |||||||||||||