GNRB Arthrometer Research Articles

GNRB® Knee Arthrometer: Inter- and Intra-observer Reliability and Learning Curve.

Background Diagnosing anterior cruciate ligament rupture is challenging, particularly due to the subjective nature of clinical laxity assessments. Objective evaluation methods are necessary for consistency and publication in clinical research. This study aims to assess the reproducibility of the GNRB® knee arthrometer (GeNouRoB, Laval, France) across different examiners and to examine the associated learning curve for a junior examiner. Methods Anterior translation measurements were conducted on 20 healthy knees using the GNRB arthrometer. Two examiners, a senior and a junior, performed the measurements independently and were blinded to each other's results. Measurements were taken at two different push forces (134 N and 200 N). The study evaluated inter- and intra-observer reproducibility using Cohen's kappa coefficient and the intraclass correlation coefficient (ICC). The junior examiner also performed a thirdseries of measurements to assess the learning curve. Results The senior examiner demonstrated excellent reproducibility with an ICC greater than 0.75 for all measurements. The junior examiner's reproducibility varied from fair to good, with an ICC ranging from 0.45 to 0.75. Inter-observer reproducibility between the senior and junior examiners was excellent (ICC >0.75). Notably, the junior examiner's reproducibility improved to an excellent level (ICC >0.75) during the second series of measurements. Conclusion The GNRB system provides a reproducible method for evaluating anterior knee laxity across different examiners. A learning curve of approximately 20 knees is sufficient for a junior examiner to achieve statistically excellent reproducibility.

Suture-tape augmentation of anterior cruciate ligament reconstruction: a prospective, randomised controlled trial (STACLR)

BackgroundAnterior cruciate ligament (ACL) reconstruction aims to restore anteroposterior and rotatory stability to the knee following ACL injury. This requires the graft to withstand the forces applied during the process of ligamentisation and the rehabilitative period. We hypothesise that the use of suture tape augmentation of single bundle ACL reconstruction (ACLR) will reduce residual knee laxity and improve patient-reported outcomes at 2-year follow-up. We will conduct a 1:1 parallel arm single-centre randomised controlled trial comparing suture tape augmented ACLR to standard ACLR technique.MethodsThe study design will be a parallel arm 1:1 allocation ratio randomised controlled trial. Sixty-six patients aged 18 and over waitlisted for primary ACLR will be randomised. Patients requiring osteotomy and extra-articular tenodesis and who have had previous contralateral ACL rupture or repair of meniscal or cartilage pathology that modifies the post-operative rehabilitation will be excluded. The primary outcome measure will be the side-to-side difference in anterior tibial translation (measured on the GNRB arthrometer) at 24 months post-surgery. GNRB arthrometer measures will also be taken preoperatively, at 3 months and 12 months post-surgery. Secondary outcomes will include patient-reported outcome measures (PROMs) collected online, including quality of life, activity and readiness to return to sport, complication rates (return to theatre, graft failure and rates of sterile effusion), examination findings and return to sport outcomes. Participants will be seen preoperatively, at 6 weeks, 3 months, 12 months and 24 months post-surgery. Participants and those taking arthrometer measures will be blinded to allocation.DiscussionThis will be the first randomised trial to investigate the effect of suture-tape augmentation of ACLR on either objective or subjective outcome measures. The use of suture-tape augmentation in ACLR has been associated with promising biomechanical and animal-level studies, exhibiting equivalent complication profiles to the standard technique, with initial non-comparative clinical studies establishing possible areas of advantage for the technique. The successful completion of this trial will allow for an improved understanding of the in situ validity of tape augmentation whilst potentially providing a further platform for surgical stabilisation of the ACL graft.Trial registrationAustralia New Zealand Clinical Trial Registry ACTRN12621001162808. Universal Trial Number (UTN): U1111-1268-1487. Registered prospectively on 27 August 2021

Outcomes of Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction According to GNRB Arthrometer Measurement

Background and Objectives: To investigate the prognosis of combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction, we used a GNRB (Genourob, Laval, France) arthrometer to measure surgical outcomes. Materials and Methods: This retrospective study reviewed patients who underwent combined ACL and ALL reconstruction and had a minimum follow-up of 2 years. Subjective outcomes, namely the International Knee Documentation Committee (IKDC) evaluation form scale scores and Lysholm scores, were evaluated preoperatively and postoperatively. We used a GNRB arthrometer to test the side-to-side laxity under pressures of 134 and 200 N, and we calculated the differential of the slope of the curves. We also recorded complications. Results: Our study examined 18 patients (mean age: 30.56 ± 8.9 years, range: 19-53) with a mean follow-up of 27.37 ± 3.4 months (range: 24-36). Both Lysholm and IKDC scores were significantly improved following the operation. The GNRB arthrometer measured mean anteroposterior laxity side-to-side as 0.76 ± 0.78 mm and 0.82 ± 0.8 mm under pressures of 134 and 200 N, respectively. The mean side-to-side differential slope under 200 N was 3.52 ± 2.17 μm/N. These values indicated that patients displayed no graft tear or low functional knee instability. All patients had a grade 3 pivot shift preoperatively; only two patients had a grade 1 pivot shift postoperatively, with the rest having a negative pivot shift. Conclusions: Our study revealed that combined ACL and ALL reconstruction has an excellent prognosis. GNRB measurement demonstrated excellent stability, and most patients had no residual pivot shift.

A novel home-based rehabilitative knee brace system is a viable option for postoperative rehabilitation after anterior cruciate ligament reconstruction: a report of 15 cases

PurposeTo investigate the functional outcomes for patients who used a novel home-based rehabilitative system during the postoperative period after anterior cruciate ligament (ACL) reconstructions.MethodsPatients undergoing ACL reconstruction surgeries were prospectively enrolled. A home-based rehabilitation system, which is composed of a knee brace with a motion tracker, a mobile app, and a web portal, was applied. Patients could complete the rehabilitation exercise through the audio guidance and the real-time tracking system which displayed the achieved motions on the user interface of the app. Feedbacks from the patients, including the International Knee Documentation Committee (IKDC) scores, were collected and uploaded to the web portal. Each patient would meet a specialized physical therapist face-to-face once a month. At postoperative 6 months, every patient received a GNRB arthrometer examination and a Cybex isokinetic dynamometer examination.ResultsA total of 15 patients (10 males and 5 females) were enrolled and followed for at least 6 months. The mean time of return to full knee extension was 1.5 months.The mean difference in laxity measured by GNRB arthrometer at 134 N significantly improved at postoperative 6 months (1.8 ± 1.6 mm) compared to that measured preoperatively (3.4 ± 1.9 mm) (p = 0.024). The peak torques of flexor and extensor muscles measured by Cybex isokinetic dynamometer remained unchanged at postoperative 6 months (p = 0.733 and 0.394, respectively). The patients’ IKDC score became smaller at postoperative 1 month (p = 0.011) and significantly improved at postoperative 6 months (p = 0.002).ConclusionUsing a home-based rehabilitative knee brace system after ACL reconstruction is a viable option as patients maintained their knee muscle strengths maintained their muscle strength and achieve similar or better knee range of motion six months postoperatively.

The lateral femoral notch sign and coronal lateral collateral ligament sign in magnetic resonance imaging failed to predict dynamic anterior tibial laxity

PurposeTo investigate the relationship between the lateral femoral notch sign as well as the coronal lateral collateral ligament (LCL) sign and anterior tibial translation using the GNRB arthrometer in patients with anterior cruciate ligament (ACL) injuries.MethodsForty-six patients with ACL injuries were retrospectively included from May 2020 to February 2022; four patients were excluded due to incomplete data. Magnetic resonance imaging (MRI) were reviewed for the lateral femoral notch sign and the coronal LCL sign. The GNRB arthrometer was used to evaluate the dynamic anterior tibial translation of the knee, and the side-to-side differences (SSDs) in tibial translation between the injured knee and healthy knee were calculated at different force levels. Two types of slopes for displacement-force curves were acquired.ResultsSix patients (14.3%) had the positive lateral femoral notch sign (notch depth > 2.0 mm), and 14 patients (33.3%) had the positive coronal LCL sign. The SSD of the anterior tibial translations under different loads as well as the slopes of displacement-force curves were the same in the positive and negative notch sign groups (p all > 0.05) and between the positive and negative coronal LCL sign groups (p all > 0.05). Meanwhile, the measured notch depth and notch length were also not significantly correlated with the anterior tibial translation SSD in the GNRB.ConclusionThe presence of the lateral femoral notch sign and the coronal LCL sign did not indicate greater dynamic tibial laxity as measured using the GNRB.

Randomized controlled trial of all-inside and standard single-bundle anterior cruciate ligament reconstruction with functional, MRI-based graft maturity and patient-reported outcome measures

BackgroundAll-inside anterior cruciate ligament reconstruction (ACLR) is a novel technique that has gained attention due to its minimally invasive and graft-saving properties. However, studies comparing MRI-based graft maturity between all-inside and standard ACLR are lacking.PurposeThis study focused on the functional, knee laxity, and MRI-based graft maturity characteristics of all-inside and standard single-bundle ACLR.Study DesignRandomized controlled trial (RCT).MethodsFifty-four patients were randomly assigned to an all-inside reconstruction group (n = 27) or standard reconstruction group (n = 27). Using the same rehabilitation strategy. The Tegner, International Knee Documentation Committee, and Lysholm scores were recorded at postoperative months 3, 6, and 12 to assess functional recovery. MRI was conducted to measure the signal/noise quotient (SNQ) of the intra-articular graft to assess the maturity. A higher SNQ indicates lower graft maturity. Knee laxity was assessed using GNRB arthrometer at the postoperative month 12.ResultsThe graft SNQ of the all-inside group was significantly higher than that of the standard group at postoperative month 6 (p < 0.05). There was no statistical difference in graft SNQ between the two groups at postoperative months 3 and 12 (p > 0.05). Both groups exhibited the highest SNQ in the middle region of the graft, followed by the proximal region, and the distal region. Functional scores improved significantly for both groups and had no statistical difference (p > 0.05). The knee laxity was higher in the all-inside group (p < 0.05) at postoperative month 12. There was no correlation between the functional scores and graft maturity in both groups (p > 0.05).ConclusionsAll-inside and standard single-bundle ACLR show good functional outcomes; however, knee laxity was relatively higher in the all-inside ACLR group than in the standard ACLR group. Moreover, both techniques exhibited poor maturity in the middle graft region and the best in the distal region. Graft maturity with all-inside ACLR is inferior to that with standard ACLR in the early postoperative stages. There is no correlation between knee function and graft maturity.Trial registrationClinical trial registration numbers: ChiCTR1800018543.Date of registration: 09/23/2018.

Arthroscopic suture-fixation of anterior tibial intercondylar eminence fractures by retensioning of the ACL and hollowing of the tibial footprint: Objective and subjective clinical results in a paediatric population

IntroductionAnterior tibial intercondylar eminence fractures (ATIEF) of the knee are rare in children. They are associated with prefracture intraligamental distention of the anterior cruciate ligament (ACL). ObjectiveThe objective of this study was to evaluate the subjective and objective clinical results of an arthroscopic surgical technique by suture-fixation of the fracture and tensioning of the ACL through hollowing of the tibial footprint. HypothesisSuture-tensioning of ATIEF arthroscopically helps to achieve treatment objectives by leaving the knee joint free of any hardware. Materials and methodsThis single-operator monocentric retrospective study involved twenty children operated on over a period of 2-years and 10 months, from March 2013, and with a minimum of one-year follow-up. Surgery was indicated for Stage II to IV fractures according to the Meyers and McKeever classification. Type I fractures were excluded. Seventeen out of 20 patients were reviewed. The median age was 12 years at the time of surgery and the mean follow-up was 28 months. The fractures were 5 of stage II, 9 of III and 3 of IV. The scores of Lysholm, objective and subjective IKDC were collected. Residual objective laxity was measured using the GNRB arthrometer at 150N. A standard X-ray evaluation permitted detection of possible growth disorders. ResultsAt 28 months of mean follow-up, the mean scores of Lysholm and subjective IKDC were 99 (95; 100) and 97 (92; 100), respectively. As for the objective IKDC, 14 knees were rated A and 3 were rated B. The mean differential residual laxity via GNRB was 0.94mm (0; 2.4). No radiological growth disorder was observed at the last follow-up. ConclusionThe ACL suture-tensioning technique is simple and reliable. It also preserves the joint of the adult to remain free of any residual hardware. Level of evidenceIV; retrospective cohort study.

The Comparison of Clinical Result between Primary Repair of the Anterior Cruciate Ligament with Additional Internal Bracing and Anatomic Single Bundle Reconstruction-A Retrospective Study.

Background: The current standard of treatment of anterior cruciate ligament (ACL) is reconstruction (ACLR). This technique has some disadvantages: poor proprioception, donor site morbidity and the inability to restore joint kinematics. ACL repair could be an alternative treatment. The purpose of the study was to compare the stability and the function after ACL primary repair versus single-bundle ACLR. Methods: In a retrospective study, 12 patients underwent primary ACL repair with internal bracing, 15 patients underwent standard ACLR. Follow-up examinations were evaluated at up to 2 years postoperatively. One patient in the ACL repair group was lost to follow-up due to re-rupture. The absolute value of anterior tibial translation (ATT) and the side-to-side difference in the same patient (ΔATT) were evaluated using the GNRB arthrometer. The Lysholm knee scoring was obtained. Re-ruptures and other complications were recorded. Results: Anterior tibial translation (ATT) was significantly decreased in the ACL repair group compared with the ACLR group (5.31 mm vs. 7.18 mm, respectively; p = 0.0137). Arthrometric measurements demonstrated a mean side-to-side difference (ΔATT) 1.87 (range 0.2 to 4.9) mm significantly decreased compared to ACLR 3.36 (range 1.2–5.6 mm; p = 0.0107). The mean Lysholm score was 85.3 points in the ACL repair group and 89.9 in ACLR group. No significant differences between ACL repair and ACLR were found for the Lysholm score. There was no association between AP laxity and clinical outcomes. There were two complications in the internal bracing group: one patient had re-rupture and was treated by ACLR, another had limited extension and had arthroscopic debridement. Conclusions: Anterior tibial translation was significantly decreased after ACL repair. Additionally, the functional results after ACL repair with internal bracing were comparable with those after ACLR. It should be noted that the two complications occurred. The current study supports further development of ACL repair techniques.

The bone microstructure from anterior cruciate ligament footprints is similar after ligament reconstruction and does not affect long-term outcomes

PurposeThe purpose of this study was to assess the quality of the bone tissue microstructure from the footprints of the anterior cruciate ligament (ACL) and its impact on late follow-up outcomes in patients who undergo anterior cruciate ligament reconstruction (ACLR).MethodsThe records of 26 patients diagnosed with a completely torn ACL who underwent ACLR were collected. During the surgery performed using the Felmet method, bone blocks from the native ACL footprints were collected. The primary measurements of the bone microstructure were made using a microtomographic scanner. In late follow-up examinations, a GNRB arthrometer was used.ResultsThere was no significant difference in the bone microstructure assessed using micro-CT histomorphometric data according to the blood test results, plain radiographs, age or anthropometric data. There was no difference in the bone volume/total volume ratio or trabecular thickness in the area of the native ACL footprints. Routine preoperative examinations were not relevant to the quality of the bone microstructure. The elapsed time from an ACL injury to surgery had no relevance to the results of arthrometry.ConclusionThe similarities in the microstructure of bone blocks from ACL footprints from the femur and tibia allow the variable use of these blocks to stabilize grafts in the Felmet method. The bone microstructure is not dependent on the time from injury to surgery. Histomorphometric values of the structure of the femoral and tibial ACL footprints have no impact on the long-term stability of the operated knee joint.Trial registrationThe approval of the Bioethics Committee of the Silesian Medical Chamber in Katowice, Poland (resolution 16/2014) was given for this research.Level of evidenceII.

Kinetic and Kinematic analysis of ACL reconstruction in association with lateral-extrarticular tenodesis of the knee in revision surgery: a pilot study.

Background.Anterior cruciate ligament reconstructions are a very frequent surgery. The key role of the anterolateral ligament in the knee rotational stability has been undelighted in recent years. Extra-articular tenodesis in association with ACL reconstructions, serves to eliminate anterolateral rotatory instability. The aim of our study is to compare treated knees with the contralateral uninjured knee in those cases whom been treated with ACL arthroscopic reconstruction and lateral extra-articular tenodesis in revision surgery, and evaluate clinical results with kinematic and kinetic examinations methods.Materials and methods.Sixteen patients (10 males and 6 females) with ages from 21 to 37 had been treated at the Orthopaedic Clinic of Udine for failure of previous ACL reconstruction. In all patients was performed ACL arthroscopic reconstruction with the association of a lateral extra-articular tenodesis (Coker-Arnold). We have decided to asses the patients at one year after surgery with GNRB arthrometer and Bioval inertial sensor system.Results.All patients treated with arthroscopic ACL reconstruction and lateral extra-articular tenodesis have regained pre-injury sagittal knee stability and gait dynamics.Conclusions.Clinical and instrumental evaluation showed how a combination of procedures can restore the kinematic and stability of a joint, even if the procedures performed are not anatomical. These are only preliminary data. (www.actabiomedica.it)

Validity of the Genourob arthrometer in the evaluation of total thickness tears of anterior cruciate ligament

ObjectiveOur purpose was to evaluate the validity and reliability of the laxity with the GNRB arthrometer in subjects with anterior cruciate ligament injury. Material and methodA diagnostic study was performed by three operators using the Genourob arthrometer, measuring the displacement of the anterior cruciate ligament. The concordance was assessed by the intraclass correlation coefficient mixed effects model, Lin correlation coefficient and graphic method from Bland-Altman. Using the anterior cruciate ligament tear as a dependent variable and the Genourob measurement as an independent variable, a logistic regression was determined. ResultsObtaining the complete information of 157 knees. The measurements with the Genourob arthrometer distributed symmetrically, with mean ± standard deviation of knees with anterior cruciate ligament injury: 5.64 ± 1.72 and knees without anterior cruciate ligament injury: 3.29 ± 1.72. The ICCs as well as the LCCs were equal to or greater than 0.99. The BA showed discrepancy for a pair of observations no greater than 7.64%. The odds ratio of the knee displacement measurement for the presence of anterior cruciate ligament injury was 4.04 (95% CI: 2.59–6.32; p-value < .01) with a ROC area of 0.863 (95% CI: 0.789–0.9456). The cut-off point of the anteroposterior knee displacement located at 6.8 mm determined a sensitivity of 74.4% and specificity of 93.8%, with a Youden Index = 0.67. ConclusionThe Genourob arthrometer is reliable and valid to establish where laxity values correlate with total thickness tears of the anterior cruciate ligament.

Effect of Femoral Tunnel Position on Stability and Clinical Outcomes After Single-Bundle Anterior Cruciate Ligament Reconstruction Using the Outside-In Technique

To evaluate the effects of the femoral tunnel location in the femoral footprint of the anterior cruciate ligament (ACL) on postoperative knee stability and clinical outcomes after ACL reconstruction (ACLR) using the outside-in technique. From December 2012 to August 2014, ACLR was performed using the outside-in technique in 137 patients. Among these patients, those who had a follow-up period of over 2years were retrospectively reviewed. A total of 102 patients met the inclusion criteria. The relative location of the femoral tunnel in the lateral condyle was evaluated as a percentage using the standardized grid system on a 3-dimensional computed tomography image. Each patient was then classified into the anterior group, center group (anteroposterior plane, 29.3% ± 3.5%), or posterior group depending on the location of the femoral tunnel. Knee laxity was evaluated using a GNRB knee arthrometer, stress radiography, and the pivot-shift test. From a clinical perspective, patient-reported outcomes (International Knee Documentation Committee subjective form and Lysholm knee score) were then evaluated. Of 102 patients, 31 (30.4%) were assigned to the anterior group, 46 (45.1%) were assigned to the center group, and 25 (24.5%) were assigned to the posterior group. Postoperative side-to-side differences, which were measured usingstress radiographs and the GNRB arthrometer, were significantly smaller in the posterior group (1.7 ± 0.6mm and 1.5 ± 0.5mm, respectively) than in the center group (2.3 ± 0.9mm and 2.2 ± 2.8mm, respectively) and anterior group (2.4 ± 0.7mm and 2.4 ± 1.3mm, respectively) (P= .002 for stress radiography and P= .002 for GNRB arthrometer). No significant between-group differences were observed in the pivot-shift test results and patient-reported outcomes among the 3 groups. The location of the femoral tunnel in the anatomic ACL footprint did not affect postoperative stability and clinical outcomes in the case of ACLR using the outside-in technique. Level III, retrospective comparative study.

Diagnostic Tools for Acute Anterior Cruciate Ligament Injury: GNRB, Lachman Test, and Telos.

PurposeThe purpose of this study is to compare the accuracy of the GNRB arthrometer (Genourob), Lachman test, and Telos device (GmbH) in acute anterior cruciate ligament (ACL) injuries and to evaluate the accuracy of each diagnostic tool according to the length of time from injury to examination.Materials and MethodsFrom September 2015 to September 2016, 40 cases of complete ACL rupture were reviewed. We divided the time from injury to examination into three periods of 10 days each and analyzed the diagnostic tools according to the time frame.ResultsAn analysis of the area under the curve (AUC) of a receiver operating characteristic curve showed that all diagnostic tools were fairly informative. The GNRB showed a higher AUC than other diagnostic tools. In 10 cases assessed within 10 days after injury, the GNRB showed statistically significant side-to-side difference in laxity (p<0.001), whereas the Telos test and Lachman test did not show significantly different laxity (p=0.541 and p=0.413, respectively).ConclusionsAll diagnostic values of the GNRB were better than other diagnostic tools in acute ACL injuries. The GNRB was more effective in acute ACL injuries examined within 10 days of injury. The GNRB arthrometer can be a useful diagnostic tool for acute ACL injuries.

Return to Sport after ACL Reconstruction using Hamstring Tendon: Analyzing 51 Cases from Maltas Hospital in Dakar

The anterior cruciate ligament (ACL) rupture is a frequent lesion in athletes. It is incompatible with the practice of high-level sport, especially pivot and contact-pivot ones. The purpose of the ACL reconstruction is to allow the athlete to resume the practice of same sport at the same level. The study involved 51 sports patients operated for ACL reconstruction at the Order of Malta’s Hospital center in Dakar during the period from 1 January 2011 to 31 May 2014. The average age of patients was 26.3 years with a male predominance (92.15%). These were professional athletes in 37.25%, amateur in 31.37%, and leisure in 31.37% of the cases. The sport was contact-pivot in 96.6% of the cases, mainly football. The objective functional evaluation was performed using the Lysholm-Tegner scale and laximetry using the GNRB arthrometer. The overall sporting recovery rate was 96% with 54.9% recovery in the same sport at the same level. Professional athletes were 42 times more likely to resume the same sport at the same level as amateurs. Recovery times were 4.7 months for line sports, 9.2 months for pivot / contact-pivot and 11.3 months for the resumption of competition. These delays were shorter for professionals with a return to pivot sport at 8 months. Apprehension and fear of a new injury were the main reason for sport's downtime or decline. Functional and anatomical results were good with a mean Lysholm score of 91% and a GNRB differential of 2.87. No independent factor was predictive of returning to sport at the same level. Returning to sports activity is very likely after an ACL ligamentoplasty, but the return to the same sport at the same level is more uncertain, in the order of 55% despite satisfactory anatomical and functional results, confirming the important role of other factors such as psychological coaching and sport-specific rehabilitation.

A prospective study to evaluate the clinico-radiological outcomes of arthroscopic single bundle versus double bundle anterior cruciate ligament reconstruction.

The aim of the study was to compare clinical and radiological outcomes of arthroscopic single-bundle versus double-bundle anterior cruciate ligament (ACL) reconstruction. 60 patients with isolated ACL injury were divided into single bundle (SB) (n=30) and double bundle (DB) reconstruction groups (n=30) and operated between July 2009 and July 2012. Outcome evaluation was performed using GNRB arthrometer, International Knee Documentation Committee & Lysholm scale. Rotational stability was determined by lateral pivot-shift test. Magnetic resonance imaging (MRI) was performed postoperatively to compare the reconstructed ACL graft orientation. Average follow-up was 34.8 months in SB and 36.2 months in DB group. At final follow-up, mean Lysholm score was 94.13±2.67 in SB and 93.13±3.31 in DB group (P value=0.202, statistically non-significant). All patients in both groups were in grade A or B according to objective IKDC scores. Mean differential anterior tibial translation was 1.45±0.6mm in SB and 1.17±0.8mm in DB group (P value=0.105, NS). All had negative pivot shift test in DB group while 2 patients had positive pivot shift in SB group. MRI of operated knees showed that values of mean sagittal ACL graft-tibial angle and mean coronal ACL graft-tibial angle were comparable in both groups (P value>0.05, NS). There was no statistically significant difference concerning knee stability, knee scores, subjective evaluations, and MRI evaluation of graft inclination angles between single- and double-bundle ACL reconstruction groups at an average of 35 months of follow-up.

Comparison of the Modified Transtibial Technique, Anteromedial Portal Technique and Outside-in Technique in ACL Reconstruction.

PurposeTo compare clinical and radiographic results of anterior cruciate ligament (ACL) reconstruction using modified transtibial technique (mTT), anteromedial (AM) portal technique and outside-in (OI) technique.Materials and MethodsFrom March 2007 to December 2012, ACL reconstruction was performed using the mTT, AM portal technique and OI technique in 20 patients each. Anteroposterior and rotational stability were assessed using the GNRB arthrometer and pivot-shift test. Femoral tunnel obliquity was measured on the anteroposterior and lateral radiographs.ResultsTegner score, Lysholm score, International Knee Documentation Committee score, pivot-shift test were improved at final follow-up in all three groups. However, statistical difference was not shown. Side-to-side difference in GNRB arthrometer was average of 1.4 mm, 1.0 mm and 0.9 mm in mTT, AM and OI group, showing the signicant difference between mTT and AM/OI groups (p<0.001). The mean femoral tunnel obliquity was 56.4° in the mTT group, 39.4° in the AM group and 33.6° in the OI group, showing significant intergroup difference (p<0.001). It showed the significant difference among three groups (p<0.001).ConclusionsClinical results were improved in all three groups. Femoral tunnel obliquity in AM and OI were more horizontal on the coronal plane. They are thought to have more benefits in oblique positioning of the grafted ACL in rotational stability; however, there was no significant difference among three techniques in pivot-shift test to assess the rotational stability in this study.

Anterior Cruciate Ligament Reconstruction in Children With A Quadrupled Semitendinosus Graft

The management of anterior cruciate ligament (ACL) tears in growing patients must balance activity modification with the risk of secondary (meniscal and cartilaginous) lesions, and surgical intervention, which could adversely affect skeletal growth. Many ACL reconstruction techniques have been developed or modified to decrease the risk of growth disturbance. We have not found any description of ACL reconstruction using a single hamstring, short graft implanted into intraepiphyseal, retroreamed sockets. Our hypothesis was that the technique that we used restored the knee stability and did not cause any growth disturbances. We retrospectively studied 28 patients (20 boys, 8 girls) who presented with a unilateral ACL tear and open growth plates. We performed short graft ligament reconstruction with the semitendinosus folded into 4 strands around 2 polyethylene terephthalate tapes. The graft was implanted into sockets that were retroreamed in the femoral and tibial epiphysis and the tapes were fixed remotely by interference screws. After a minimum period of 2 years, we evaluated the comparative knee laxity, the radiographic limb morphology, the appearance of secondary lesions, and the functional outcomes using the Lysholm and Tegner scores. Comparative analyses were performed using the Student t test with subgroups depending on the type of fixation used. The mean age of the patients was 13 years (range, 9 to 15 y). The mean follow-up was 2.8 years (range, 2 to 5 y). The mean difference in laxity at 134 N was 0.3 mm, as determined using a GNRB arthrometer. No patients reported meniscal symptoms or degenerative changes. We found no angular deformity or leg length inequality. Two patients suffered a recurrent ACL tear. The preliminary results from this series are consistent with prior studies demonstrating that intraepiphyseal ACL reconstruction is a safe reliable alternative for the pediatric population. Case series; level of evidence 4.

A new knee arthrometer, the GNRB ®: Experience in ACL complete and partial tears

Clinical diagnosis of anterior cruciate ligament (ACL) tears (Lachman test and Pivot shift test in valgus and internal rotation) is reliable in case of complete ACL tear but reveals elusive in case of partial tears. Quantitative assessment of anterior tibial translation proves to be imprecise, subjective and poorly reproducible especially with the KT-1000 arthrometer. We developed the GNRB, an alternative original anterior knee laxity measurement device. The lower limb is placed in a rigid support with the knee at 0 degrees of rotation, the restraining power being recorded. A 0-250 N thrust force is transmitted by a jack to the upper segment of the calf. This force is only applied in the absence of hamstring muscles contraction. Displacement of the anterior tibial tubercle is recorded using a sensor with a 0.1mm precision. We hypothesize that this knee laxity measurement device is more reliable and reproducible than other currently available arthrometers. During a first validation study, the GNRB was compared to the KT-1000 arthrometer, in 20 pairs of healthy knees, measurements being performed by two investigators. Variance analyses were carried out at 134 N. In a second clinical study, 21 complete ACL tears (the notch is devoid of ACL) and 24 partial ACL tears (anterior or posterior bundle tear and cicatricial ACL remnant in continuity) were tested with these arthrometers to exact a differential laxity threshold value between both knees at 250 N. Statistical analysis was subsequently performed using variance and ROC curves analysis. The GNRB arthrometer reveals to be significantly more reproducible than the KT-1000, irrespectively of the tester's experience level. Moreover, unlike the KT-1000, the achieved measurement is independent from the uninvolved side. Reproducibility of laximetry proves to be significantly better with the GNRB than with the KT-1000, wherever the examiner's experience stands and whatever the evaluated side condition could be. When differential laxity threshold value was 3mm in complete ACL tears, sensitivity was 70% and specificity 99% at 134 N. Using a 1.5mm threshold value in ACL partial tears, the arthrometer sensitivity was 80% and specificity was 87% at 134 N. Reproducibility of laximetry was significantly better with the GNRB than the KT-1000 device, wherever the examiner's experience stands and whatever the evaluated side-condition could be. The GNRB reports various supplementary advantages compared with other available laximeters. Good control of the investigated limb position in rotation, recording of translation in the absence of hamstring muscles contraction and in direct comparison with the KT-1000: reproducibility, constant pressure, arthrometry improved accuracy and automated measurements recording. The GNRB might be used for diagnosis of partial and complete ACL tears and during follow-up of reconstructed or not ACL tears. type II. Prospective comparative study.