The Biomechanical And Clinical Study Of Posterior Medial Corner Combined With Anterior Cruciate Ligament Injury

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Medial collateral ligament reconstruction is necessary to restore anterior stability with anterior cruciate and medial collateral ligament injuryObjective: The anterior cruciate ligament(ACL)is the main stabilizer against anterior tibial translation,and The s MCL is the primary static medial stabilizer of the knee and is situated in the second layer,Both the ACL and MCL full important kinematic functions,and it is not uncommon for s MCL damage to occur with ACL injury and has been reported to occur in between 20 and 38% of all cases.Medial collateral ligament reconstruction has been a topic of controversy in regard to the need for surgical intervention as well as the method of reconstruction.Some clinical studies have found MCL reconstruction was not necessary in the combined injury,others have shown a benefit to stability in reconstructing both the ACL and MCL in combined injuries.several study suggested that with MCL injury,the ACL graft may be subjected to additional loads and elongate with time.With regard to the MCL reconstruction technique,Borden et al presented a double-bundle MCL reconstruction technique to reestablished both the anterior and posterior stabilizing components of the MCL.Dong et al presented a triangular vector MCL reconstruction technique and reported restored valgus and rotational stability.While there is clinical interest in multi-ligamentous injury,there has been few studies of the biomechanical effects of combined ACL and s MCL reconstruction.The purpose of this study was to compare knee kinematics and graft forces in anterior cruciate ligament(ACL)reconstruction combined with one of two superficial medial collateral ligament(s MCL)reconstruction techniques(parallel or triangular vector s MCL reconstruction).Method: Twenty porcine knees were divided into two groups(n = 20),parallel or triangular vector s MCL reconstruction,with both groups having anatomic single-bundle ACL reconstruction.The knees were tested under(1)an 89-N anterior tibial load,(2)4 Nm internal and external rotational tibial torques,and(3)a 7 Nm valgus torque.Both groups were tested with the following order during the progression of the study:(1)intact ACL,(2)deficient s MCL with intact ACL,(3)s MCL reconstruction with intact ACL,(4)s MCL reconstruction and ACL reconstruction,(5)s MCL deficient with ACL reconstruction,and(6)s MCL deficient with ACL deficient.Results: With ACL/s MCL co-injuries,SB ACL reconstruction alone did not restore the intact knee ATT.SB ACL reconstruction and both s MCL reconstructions restored ATT at 30° extension;however,at 60° and 90° of knee extension,the triangular vector s MCL reconstruction restored ATT,while the parallel s MCL reconstruction did not.Under valgus loading,SB ACL reconstruction alone did not restore intact knee stability,while the parallel s MCL reconstruction restored stability and the triangu-lar vector method did not.With an internal tibial torque,both s MCL reconstruction techniques restored intact knee internal rotation and under an external tibial torque,parallel s MCL reconstruction restored.External rotation while triangular vector s MCL reconstruction did not restored.Under AT loading,with combined SB ACL and s MCL reconstruction the force in the ACL and s MCL grafts are lower and higher,respectively,than the native tissue.The in situ force of the native ACL was not restored by the SB ACL reconstruction.With an IR torque,s MCL deficiency increases the force in the native ACL.The in situ force of the native ACL under IR(internal rotational)loading with ACL reconstruction alone was not restored for either group.The in situ force of the native ACL when the s MCL is removed is significantly different under IR loading to the state where both the native ACL and s MCL are intact.The in situ force of the native ACL was not restored for parallel s MCL reconstruction at 60° of knee extension and also was not restored with ACL reconstruction alone in the parallel s MCL group at 60° of knee exion.Under a valgus load, the force in the ACL and ACL graft was increased with s MCL deficiency but restored with s MCL reconstruction.With ER(external rotational)loading,the in situ force in the ACL was significantly different from intact ACL with s MCL deficiency,but restored with s MCL reconstruction.Summary: This study showed that single-bundle ACL reconstruction alone was not able to restore anterior tibial translation,valgus rotation,and external rotation of the intact knee with combined ACL and s MCL injuries and s MCL reconstruction was also required.The combined ACL and parallel s MCL reconstruction better restored valgus and external rotation stability,while the combined ACL and triangular vector method better restored anterior tibial translation.With combined ACL and severe s MCL injury,both ligaments should be reconstructed.The two s MCL reconstruction techniques exhibited slightly different kinematics and graft force;however,there was not enough difference to recommend one over the other.Part ? Surgical Treatment of Acute Grade III Medial Collateral Ligament Injury Combined With Anterior Cruciate Ligament Injury: Anatomic Ligament Repair Versus Triangular Ligament ReconstructionObjectives: In the clinic,isolated grade III MCL injury is very rare,and the risk of concomitant ligament injury is 78%.Of cases with concomitant ligament injuries,95% involve the anterior cruciate ligament(ACL).The treatment of MCL injury has evolved from nonoperative management to aggressive surgical repair or reconstruction.Most MCL injury cases(Hughston grade I or II3)can be treated nonoperatively,leading to satisfactory clinical outcomes.4-6 Surgical treatment of MCL injuries has been proposed for severe valgus laxity(Hughston grade III)with associated ligament injuries or patients with chronic injuries.A recent review by Grant et al suggested that ACL reconstruction should be performed in a subacute time frame once full motion has returned.Valgus instability should be assessed at that time and MCL repair or recon-struction performed in those patients with persistent valgus instability.However,MCL repair is not a good choice in a subacute time frame because the MCL would have incomplete healing and scarring and would be very difficult to identify in a subacute time frame;revision of those structures could hardly yield a satisfactory clinical result.More importantly,from a functional perspective,the MCL and ACL both contribute to maintaining rotational stability and the rotatory instability would be aggravated if these structures were simultaneously injured.A triangular-vector MCL reconstruction technique has been reported and proved to restore both valgus and rotational stability and anatomic ligament repair(ALR)has also been recognized as a way to restore the anatomic structure;however,we do not know whether acute anatomic augmented repair can also achieve the same clinical result.Thus the purpose of this study was to evaluate the clinical results of two techniques in the treatment of acute grade III MCL injury combined with an ACL tear with respect to imaging and functional results.Methods: Between January 2009 and October 2011,a total of 69 patients with an acute grade III MCL tear combined with an anterior cruciate ligament tear were divided into 2 groups: those who underwent ALR and those who underwent TLR.Single-bundle anterior cruciate ligament reconstruction was also performed in all patients.A radiographic stress-position imaging test was performed to evaluate excessive medial opening of the knee.In addition,the Slocum test was carried out to assess anteromedial rotatory instability before surgery and at follow-up.The subjective symptoms and functional outcomes were evaluated preoperatively and postoperatively with International Knee Documentation Committee(IKDC)assessment.Results: Sixty-four patients with a mean follow-up period of 34 months were included in the final analysis.The measurement results for medial opening at the last follow-up appointment decreased significantly from the pretreatment measurements and fell within the normal range,without a statistically significant difference between the 2 groups(P>0.05).The overall incidence of anteromedial rotatory instability was reduced to 21.9% compared with 62.5% preoperatively.However,the incidence of anteromedial rotatory instability in the TLR group(9.4%)decreased significantly compared with that in the ALR group(34.4%)(P<0.05).All patients' IKDC subjective scores significantly improved after surgery.No statistically significant difference was found between the 2 groups at the last follow-up(P>0.05).The comparison of IKDC extension and flexion deficit scores between the 2 groups showed no significant differences.Eleven patients in the ALR group and 4 in the TLR group complained of medial knee pain.The comparison between the 2 groups showed no significant difference(P>0.05).Summary: The clinical outcomes of this study showed that no major difference existed in the ALR and TLR groups based on IKDC scores and medial opening evaluations in the short-term.However,TLR offered better rotatory stability than ALR at final follow-up.Part ? An anatomical-like triangular-vector ligament reconstruction for the medial collateral ligament and the posterior oblique ligament injury with single femoral tunnel: a retrospective studyObjectives: The medial collateral ligament(MCL)is one of the most commonly injured ligamentous structures.It serves as the primary medial static stabilizer against valgus stress,though along with the posteromedial corner provides resistance to external rotation forces applied to the lower extremity.Both MCL and posterior oblique ligament(POL)are two main static stabilizers.And the combined injury could result in clinically significant valgus or rotational instability.A better recovery of valgus and rotational stability was essential for massive MCL injury,let alone one who suffer with grade III MCL injury combine ACL injury.Previous anatomical studies have demonstrated the relative position was unparalleled on different planes between MCL and POL.When the knee extended,the MCL runs parallel to the axis of the femur/tibia and the POL formed an angle of 25° with the axis of the femur/tibia.Since non-parallel,the extension lines of these two ligaments would intersect at one point at su-perior of femoral condyle.This study shows the surgical procedure of an anatomical-like triangular-vector ligament reconstruc-tion(TLR)technical of the MCL and POL which bring a satisfied result of medial knee stability.Methods: During July 2013 to May 2014,26 patients who received anatomical-like TLR were included into this study.All patients received clinical physical examination,imaging examination,and knee joint function score both preoperative and follow-up.The stability of the medial structure of the knee joint was examined by physical examination and imaging evaluation,including excessive knee medial opening(EKMO)and tibial external rotation angle(TERA).The function of the knee was evaluated by the subjective questionnaire,including Lysholm,Tegner,and IKDC score.SPSS software was used for statistics analysis.Results: The mean follow-up time exceeds 24 months.Two patients occurred with serious heterotopic ossification,and one patient received revision because of screw breakage.EKMO over the contralateral state at 0° decreased from 9.76 ± 2.76 mm to 2.79 ± 1.02 mm with statistical significance(P<.001)and 10.32 ± 2.75 mm decreased to 3.13 ± 0.85 mm at 30°(P<.001).Meanwhile,TERA significantly decreased from 53.38 ± 6.71° to 27.15±4.92°(P<.001).The postoperative Lysholm,Tegner,and IKDC score were superior to preoperative with statistical significance(P<.001).Summary: Anatomical-like TLR can reconstruct the graft to cover the insertions which can regain anatomic form and function with a cramped space.Not only the valgus stability and rotational stability can be restored obviously at follow-up but also the usage of implantation can be reduced,decreasing the incidence rate of allergy and saving costs.Conclusions: This study showed that single-bundle ACL reconstruction alone was not able to restore anterior tibial translation,valgus rotation,and external rotation of the intact knee with combined ACL and s MCL injuries and s MCL reconstruction was also required.The combined ACL and parallel s MCL reconstruction better restored valgus and external rotation stability,while the combined ACL and triangular vector method better restored anterior tibial translation.With combined ACL and severe s MCL injury,both ligaments should be reconstructed.The two s MCL reconstruction techniques exhibited slightly different kinematics and graft force;however,there was not enough difference to recommend one over the other.The clinical outcomes of this study showed that no major difference existed in the ALR and TLR groups based on IKDC scores and medial opening evaluations in the short-term.However,TLR offered better rotatory stability than ALR at final follow-up.Anatomical-like TLR can reconstruct the graft to cover the insertions which can regain anatomic form and function with a cramped space.Not only the valgus stability and rotational stability can be restored obviously at follow-up but also the usage of implantation can be reduced,decreasing the incidence rate of allergy and saving costs.