KT-1000 Measurements Research Articles

Results of ACL reconstruction with tibial Retroscrew fixation: Comparison of clinical outcomes and tibial tunnel widening

Summary. ACL reconstruction with the RetroScrew™ shows superior clinical outcomes compared to historical Achilles allograft studies with antegrade screws. Addition of antegrade screw augmentation to retrograde fixation causes an increase in tibial tunnel widening. Introduction. In traditional antegrade screw fixation of Anterior cruciate ligament (ACL) soft tissue allografts, the screw is secured in the opposite direction of graft tension, potentially altering the appropriate tension on the graft. The RetroScrew (Arthrex) is a bioabsorbable screw placed in a retrograde fashion, potentially improving the tension of the graft by placing the screw in a proximal-to-distal direction. In addition, the RetroScrew theoretically decreases tibial tunnel widening by closing the aperture of the tibial tunnel, which prevents ingress of synovial fluid. Early tunnel expansion has been implicated due to excessive transverse and longitudinal graft motion. The clinical effects of tunnel expansion have yet to be fully understood. The purpose of this study is to assess the clinical results and tunnel width after ACL soft tissue fixation in the tibia with the RetroScrew. Methods. Fifty-nine patients who underwent ACL reconstruction performed by two surgeons using the RetroScrew device returned for postoperative evaluation at an average of 25 months following surgery with a minimum follow-up of 12 months. Clinical evaluation, SF-36, IKDC and KT-1000 scores were recorded, and knee radiographs were used to measure tibial tunnel widening. Thirty-five patients had backup antegrade screw fixation in conjunction with the RetroScrew, and 24 patients had RetroScrew fixation alone. The results were compared to two previously reported studies on ACL reconstruction with Achilles tendon allograft that used antegrade screws. Results. The average IKDC score was 87 (range: 44–100), with mean KT-1000 side-to-side difference of 1.2 mm (range: 0–5 mm). Tibial tunnel widening was 4.93 mm (SD 3.32) on AP radiographs and 4.40 mm (SD 2.72) on lateral radiographs greater than the native tunnel drilling. Patients with additional backup fixation had significantly more tunnel widening than patients without backup fixation (P < 0.05). There was one failure based on KT-1000 measurements. When compared to previous studies using ACL allografts, RetroScrew patients had statistically superior Lachman exams, KT-1000 side-to-side differences and decreased tibial tunnel widening (P < 0.05) when antegrade fixation was excluded. Conclusion. Patients who underwent Achilles allograft ACL reconstruction with the RetroScrew had improved clinical results compared to historical controls using antegrade fixation. Tibial tunnel widening was increased when using additional antegrade screw fixation, suggesting that the amount of bioabsorbable material within the tibial tunnel was related to the degree of tunnel widening.

Effect of Posterolateral Bundle Graft Fixation Angles on Clinical Outcomes in Double-Bundle Anterior Cruciate Ligament Reconstruction

Background: In double-bundle (DB) anterior cruciate ligament (ACL) reconstruction, no consensus exists on an optimal setting for the posterolateral bundle (PLB) graft fixation angles. Hypothesis: Different PLB fixation angles would affect clinical outcomes in DB ACL reconstruction. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: This study prospectively included 90 patients who underwent primary DB ACL reconstruction with an autologous semitendinosus tendon. The PLB fixation angles were randomly set as follows: 0° of flexion (P0; n = 30), 20° (P20; n = 30), and 45° (P45; n = 30). In all groups, the anteromedial bundle was fixed at 20° of flexion. The following evaluation methods were used at the preoperative period and at 3, 6, and 9 months and 1 and 2 years after the surgery: clinical examination, KT-1000 arthrometer measurement, muscle strength, Tegner score, Lysholm score, and subjective rating scale regarding patient satisfaction and sports performance levels. Graft retear, contralateral ACL tear, and additional meniscus surgery were also recorded. Results: Seventy-five patients (P0, n = 25; P20, n = 26; P45, n = 24) who were followed for 2 years were evaluated. Preoperatively, there were no differences among the groups. Postoperatively, pivot-shift test results in the P0 and P20 groups were better than those in the P45 group (P0, n = 23 graded negative and 2 graded 1+; P20, n = 23 and 2; P45, n = 15 and 7, respectively; P0 vs P45: P = .038 and P20 vs P45: P = .038). Average KT-1000 arthrometer laxity measurements were better in the P20 group than in the P45 group (P0, 0.4 mm; P20, 0.3 mm; P45, 1.3 mm; P20 vs P45: P = .048), and there were more patients with graft failure (KT-1000 measurement, ≥4 mm) in the P45 group (n = 3) than the P0 and P20 groups (each, n = 0). There were no significant differences in range of motion, other laxity tests, muscle strength, Tegner score, Lysholm score, subjective rating scale, or additional surgery. Conclusion: In DB ACL reconstruction, when the anteromedial bundle was fixed at 20° of flexion, fixation of the PLB at 45° was worse than fixation at 0° and 20° with respect to anterior and rotational stability during the 2-year follow-up. KT-1000 arthrometer measurements and pivot-shift test results were significantly worse, and there were more patients with graft failure in the P45 group. There were no differences among groups in other findings.

Early comparision results of anatomical single and double bundle anterior cruciate ligament reconstruction procedures by using autogenous hamstring tendon graft

OZET: On capraz bag lezyonlarinin otojen hamstring tendon grefti kullanilarak anatomik cift band ve tek band teknigi ile rekonstruksiyonu sonrasi karsilastirmali erken donem klinik sonuclarimiz Amac: Bu calismanin amaci on capraz bag yirtigi sonrasinda anatomik cift band yontemi ve anatomik tek band yontemi kullanilarak on capraz bag (OCB) tamiri uygulanan hastalarin ameliyat oncesi ve sonrasi bul- gularini karsilastirmaktir. Gerec ve Yontem: Calismamizda 2007-2009 yillari arasinda anatomik cift band yontemiyle OCB rekons- truksiyonu ameliyati uygulanan ve yeterli takibi olan 20 hasta ile, anatomik tek band yontemiyle OCB rekons- truksiyonu ameliyati uygulanan ve yeterli takibi olan 20 hastanin sonuclari retrospektif olarak degerlendiril- di. Iki grubun Lysholm Skorlamasi sonuclari, Modifiye Cincinnati Skorlamasi sonuclari, IKDC skoru ve aktivite skalasina gore sonuclari, eklem hareket acikligi sonuclari, stabilite test sonuclari, uyluk atrofisi sonuclari, tek bacakla uzun atlama testi sonuclari ve KT-1000 cihazi ile 15, 20, 30 pound kuvvetler uygulanarak yapi- lan olcum sonuclari retrospektif olarak degerlendirildi. Iki grubun karsilastirmasinda student t testi, Mann- Whitney U testi, Anovo testi kullanilarak, p<0.05 degeri anlamli kabul edildi. ABSTRACT: Early comparision results of anatomical single and double bundle anterior cruciate ligament reconstruction procedures by using autogenous hamstring tendon graft Objective: Purpose of this study is to evaluate the results of anatomical single bundle and double bundle anterior cruciate ligament reconstruction procedures and compare the results between two groups. Material and Methods: 20 patients had been treated by anatomical single bundle (group 1) and 20 patients were treated by anatomical double bundle technique (group 2) between 2007 and 2009. The patients'; Lysholm knee scores, Modified Cincinnati scores, knee stability tests, activity scales, examination results of knee range of motion, IKDC scores, thigh atrophy measurement results, one leg hop test scores and examination under 15, 20, 30 pound forces with KT-1000 machine were evaluated and compared between two groups retrospectively. Statistical analysis was performed by using student T test, Mann-Whitney U test and Anovo test, p<0.05 was accepted as significant. Results: For group 1; 17 (85%) of the patients were male and 3 (15%) of them were female, mean age was 26 (16-36) years, 11 (55%) of the lesions were on the right knee and 9 (45%) of them were on the left knee. All of the patients in group 2 were male. For group 2; mean age was 26.7 years (18-35), 14 of the lesions (70%) were on right knee and 6 of them were on the left knee (30%). Anterior translation rates which had been tested by KT-1000 measurements with 20 and 30 pound forces were lesser for group 2 (statistically significant, p<0.05). There were no statistically significant difference for other comparisions. Conclusion: Anterior translation after anatomical double bundle technique was statistically significantly lesser than anatomical single bundle technique when tested with KT-1000 machine under 20-30 pound forces. We believe in that; after evaluating more cases' clinical results which has been treated by anatomical double bundle anterior cruciate ligament reconstruction technique, more orthopaedic surgeon will prefer

Transtibial Versus Anteromedial Portal Anterior Cruciate Ligament Reconstruction Using Soft-Tissue Graft and Expandable Fixation

To compare clinical outcomes between transtibial drilling and anteromedial portal techniques for anterior cruciate ligament (ACL) reconstruction using soft-tissue grafts secured with expandable fixation. Patients undergoing soft-tissue ACL reconstruction using expandable fixation between 2007 and 2011 were reviewed for inclusion in this study. Revision ACL cases were excluded. All surgeries were performed by 1 of 2 sports medicine fellowship-trained surgeons (T.S.D., K.D.M.). A total of 128 patients (67 comprising transtibial cohort and 61 comprising anteromedial portal cohort) had a minimum of 24 months' follow-up (mean, 27 months) and met the inclusion criteria. The patients were divided into 2 groups based on the method used for creation of the femoral tunnel. At final follow-up, outcomes were assessed with KT-1000 (MEDmetric, San Diego, CA) measurements, as well as International Knee Documentation Committee, Lysholm, and Tegner scores. Data were screened for normality and skew before use of parametric statistics and were transformed if necessary. Data were analyzed by 1-way analysis of variance with post hoc paired comparisons using the Bonferroni approximation. No differences in demographic characteristics were observed between the 2 groups. There was no significant difference in postoperative KT-1000 measurements between the 2 cohorts (1.571 ± 0.2275 mm in transtibial cohort [n = 35] and 1.246 ± 0.09249 mm in anteromedial cohort [n = 61], P = .1259). A significant improvement in International Knee Documentation Committee scores was observed in the anteromedial cohort, increasing from 41 ± 16 to 89 ± 7.4 (mean ± SD) (P < .0001). Similar changes were observed for the Lysholm score. There was no significant difference between cohorts for any postoperative scores measured (P > .2). Our data show comparable KT-1000 measurements for both anteromedial and transtibial femoral drilling techniques when using a soft-tissue graft with expandable fixation. Level IV, therapeutic case series.

Extraaarticular Reconstruction In ACL Deficient Knee: 25 Years Later

Objectives:Extraarticular Reconstructions (ERs), isolated or in association with Intraarticular ACL Reconstructions (IRs) were popular in the eighties. However they were almost completely given up as a result of a consensus conference organized by AOSSM in 1989 in Snowmass (Co) where the experts concluded that ERs, even if biomechanically justified, were unable to provide any improvement in clinical results with greater morbidity, higher risk of complications and increased rate of degenerative osteoarthritis (DOA). However, as since then the surgical techniques and postoperative rehabilitation have radically changed, it could be helpful to reconsider ERs and their long term effect on knee stability and on DOA.Methods:One hundred consecutive patients who underwent an anatomic single bundle ACL reconstruction with hamstrings were re-evaluated at a minimum follow up of eleven years. In 23 cases (group B), due to the presence of a Pivot Shift test graded as +++ or in cases of athletes involved in high risk sports, a lateral tenodesis (Coker/Arnold) was associated. The other 77 patients, where an isolated IR was performed with the same technique (group A), served as control. All patients followed the same, standard postoperative rehabilitation program. At follow up Lysholm, IKDC and Tegner activity scores were used. A side to side maximum manual (S/S MM) KT1000 measurement was done. Comparative weight bearing antero-posterior and lateral radiograms were performed and analyzed according to Fairbank, Kellgren and IKDC classification. Tibio-femoral and patella-femoral joints were analyzed separately. Statistical analysis was performed using Student t-test, Pearson chi-square test with SPPS 9.0 software.Results:Group A and B were homogeneous for sex and age. At final follow up seven patients were lost. Subjectively Lysholm score, IKDC and Tegner Activity score improved significantly in both groups with no significant difference. Objectively the number of patient categorized as A and B according to the IKDC was significantly higher in group B than in group A ( P=0.05). Considering as a failure a S/S M/M difference > 5mm or a Pivot Shift test graded as ++ or +++ or a recurrence of any giving way episode, we found 7 cases in group A and no cases in group B (P=0.006). Radiogical evaluation showed no statistically significant difference between the two groups in all scales in both femoro-tibial and patello-femoral joints.Conclusion:The main limitation of the study is that the two groups were not homogeneous in term of preoperative conditions. However as highest grades of activity level and Pivot Shift correlate with an increased risk of DOA, this limitation appears to strengthen the value of the study. Adding a lateral tenodesis to an ACL IR with hamstrings, followed by a standard rehabilitative protocol, seems not to increase the risk of development of DOA, improving rotatory knee stability and reducing risk of recurrence. The meeting in Snowmass has been a milestone event in the evaluation of role of ERs in ACL deficent knee, giving an outstanding contribution to their definition, their biomechanical effect and their role in rotatory instability. However, on the basis of the results of this study, we could speculate that the conclusions of the meeting were somewhat misleading or at least misinterpreted, as they were based on surgical techniques and rehabilitation procedures no more in use in the modern ACL surgery.

Effect of Notchplasty in Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction

Background: The effects of notchplasty on the clinical outcome after anatomic double-bundle anterior cruciate ligament (ACL) reconstruction remain unclear. Hypothesis: Anatomic ACL reconstruction with notchplasty would result in less risk of loss of extension and would provide adequate space for better graft healing, leading to better knee stability compared with anatomic ACL reconstruction without notchplasty. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 137 patients who underwent anatomic double-bundle ACL reconstruction were included. Seventy-three patients without notchplasty were classified as the control group, and 64 patients with 2-mm notchplasty were classified as the notchplasty group. The following evaluation methods were used: loss of extension, patient’s subjective feeling of limited extension and pain at passive full extension, muscle strength, manual laxity tests, KT-1000 arthrometer measurement, patellofemoral joint findings, Tegner score, Lysholm score, subjective scores, and time to return to sports. Tearing of the reconstructed ACL and additional synovectomy were recorded. Both tibial and femoral tunnel positions were measured using 2-view radiographs: a Rosenberg and a lateral view. Results: Loss of extension was larger in the notchplasty group compared with controls (at 6 months: 0.8° vs 1.4°, P = .012; at 2 years: 0.4° vs 0.9°, P = .0053). The number of patients with a feeling of limited extension was also larger in the notchplasty group (at 6 months: 13 patients graded 1+ [somewhat limited] and 2 patients graded 2+ [very limited] vs 18 graded 1+ and 6 graded 2+, P = .015; at 2 years: 2 graded 1+ and 0 graded 2+ vs 4 graded 1+ and 5 graded 2+, P = .011). Six patients in the notchplasty group required additional synovectomy because of the prolonged loss of extension, whereas no patient in the control group required additional synovectomy. There were no differences between groups regarding muscle strength, patellofemoral findings, Lysholm score, Tegner score, subjective scores, or time to return to sports. The KT-1000 arthrometer measurement was better in the notchplasty group (1.2 vs 0.4 mm, P = .0017). However, 6 patients in the notchplasty group showed an overconstrained knee (KT-1000 measurement ≤–2 mm), compared with only 1 patient in the control group. There were no differences between groups in the other manual laxity tests or the tunnel positions. Conclusion: In anatomic double-bundle ACL reconstruction, anterior stability was improved and there were no harmful effects on patellofemoral joint findings by 2-mm notchplasty; however, notchplasty likely caused overconstrained knee, leading to a need for additional synovectomy in some patients. In contrast, anatomic double-bundle ACL reconstruction without notchplasty did not increase the incidence of loss of extension or of graft failure.

NEITHER GOOD KNEE STABILITY NOR RECOVERED MUSCULAR STRENGTH GUARANTEE SAFE RETURN TO SPORTS AFTER ANATOMICAL SINGLE- AND DOUBLE-BUNDLE ACL RECONSTRUCTION

BackgroundRecent innovation in ACL reconstruction has provided improved knee stability and function, however, the effect to decrease the incidence of the second ACL injury has not been established.ObjectiveTo determine the...

Anatomic single- versus double-bundle ACL reconstruction: a meta-analysis

To determine whether anatomic double-bundle anterior cruciate ligament (ACL) reconstruction compared to anatomic single-bundle ACL reconstruction more effectively restored antero-posterior (A-P) laxity, rotatory laxity and reduced frequency of graft rupture. Our hypothesis was that anatomic double-bundle ACL reconstruction results in superior rotational knee laxity and fewer graft ruptures due to its double-bundle tension pattern, compared with anatomic single-bundle ACL reconstruction. An electronic search was performed using the PubMed, EMBASE and Cochrane Library databases. All therapeutic trials written in English reporting knee kinematic outcomes and graft rupture rates of primary anatomic double- versus single-bundle ACL reconstruction were included. Only clinical studies of levels I-II evidence were included. Data regarding kinematic tests were extracted and included pivot-shift test, Lachman test, anterior drawer test, KT-1000 measurements, A-P laxity measures using navigation and total internal-external (IRER) laxity measured using navigation, as well as graft failure frequency. A total of 7,154 studies were identified of which 15 papers (8 randomized controlled trials and 7 prospective cohort studies, n = 970 patients) met the eligibility criteria. Anatomic ACL double-bundle reconstruction demonstrated less anterior laxity using KT-1000 arthrometer with a standard mean difference (SMD) = 0.36 (95% CI 0.214-0.513, p < 0.001) and less A-P laxity measured with navigation (SMD = 0.29 95% CI 0.01-0.565, p = 0.042). Anatomic double-bundle ACL reconstruction did not lead to significant improvements in pivot-shift test, Lachman test, anterior drawer test, total IRER or graft failure rates compared to anatomic single-bundle ACL reconstruction. Anatomic double-bundle ACL reconstruction is superior to anatomic single-bundle reconstruction in terms of restoration of knee kinematics, primarily A-P laxity. Whether these improvements of laxity result in long-term improvement of clinical meaningful outcomes remains uncertain. II.

Brace or no-brace after ACL graft? Four-year results of a prospective clinical trial

A controversial discussion is held on using stabilizing knee braces after anterior cruciate ligament (ACL) surgery. The current study investigated the influence of a stabilizing knee brace on results after ACL reconstruction using patellar tendon autografts. A prospective randomized study was started including 64 patients divided into two equal groups and treated with or without a stabilizing knee brace for 6 weeks post-operatively. A follow-up examination 4 years after operation comprised IKDC 2000, KT1000 measurement, a visual analogue pain scale (VAS; scores 0-10) and radiographic evaluation. The t test for independent and paired samples and the Pearson's Chi-square test were used for statistical analysis (p < 0.05). The primary endpoint was the difference in IKDC classification. Eighty-one per cent of the patients were examined 4 years post-operatively. IKDC 2000 subjective (brace group 90.5 ± 8.9, braceless group 93.2 ± 6.1) and objective results (brace A 30%, B 56%, C 16%; braceless A 32%, B 48%, C 20%) and instrumental measurement of anteroposterior laxity with KT1000 (brace 0.6 ± 2.4 mm, braceless 1.8 ± 3.4 mm) showed no significant differences. VAS pain results were significantly better in the braceless group at 1.0 ± 1.2 versus 1.9 ± 1.4 under sports activity or heavy physical work (p = 0.015). There were no radiographic differences concerning osteoarthritic findings and tunnel widening between the groups. Post-operative treatment with a stabilizing knee brace after ACL replacement showed no advantage over treatment without a brace at 4-year follow-up. The use of a knee-stabilizing brace after isolated ACL reconstruction with autologous patellar tendon graft is not recommended. II.

Biomechanical Analysis of the Knee With Partial Anterior Cruciate Ligament Disruption: Quantitative Evaluation Using an Electromagnetic Measurement System

To investigate the biomechanical function of anterior cruciate ligament (ACL) remnants in ACL-deficient knees with both partial and complete tears. Twenty partial ACL-deficient (group P), 20 complete ACL-deficient (group C), and 40 contralateral ACL-intact knees were examined. The end point during the Lachman test, side-to-side differences of KT-1000 measurements, and the pivot shift test were evaluated. Additionally, the side-to-side difference of anterior tibial translation during the Lachman test and the acceleration during the pivot shift test were calculated using an electromagnetic measurement system (EMS). The end point was found in 9 patients in group P, whereas it was not detected in group C. In KT-1000 measurements, the mean side-to-side differences were 3.8 ± 2.4 mm in group P and 5.4 ± 2.3 mm in group C. There was a significant difference between these 2 groups (P < .05). In the pivot shift test evaluation in group P, one patient was evaluated as grade 0, 17 patients as grade 1+, and 2 patients as grade 2+. In group C, 10 patients were evaluated as grade 1+, 9 patients as grade 2+, and one patient as grade 3+. Using the EMS, mean side-to-side differences during the Lachman test were 3.1 ± 2.1 mm in group P and 7.2 ± 3.2 mm in group C. The anterior-posterior displacement in group P was significantly less than that in group C (P < .05). In the quantitative pivot shift test, the mean acceleration in the contralateral ACL-intact knees was -632.7 ± 254.5 mm/s(2), whereas it was -1107.5 ± 398.9 mm/s(2) in group P and -1652.2 ± 754.9 mm/s(2) in group C. Significant differences were detected between the 3 knee conditions (P < .05). The quantitative assessments of knees with partial ACL ruptures during the Lachman test and the pivot shift test using the EMS showed less laxity than did knees with complete ACL tears, whereas their laxity was greater than the contralateral knees with intact ACLs. Level III, diagnostic study of nonconsecutive patients.

Anterior Cruciate Ligament Reconstruction With Autografts Compared With Non-irradiated, Non-chemically Treated Allografts

Allograft anterior cruciate ligament (ACL) reconstruction obviates donor site morbidity and may accelerate postoperative recovery. However, allograft use can lead to increased rates of surgical failure, particularly when chemical processing or irradiation is used. Few studies have rigorously evaluated the comparative outcomes of autografts and fresh-frozen allograft tissue for ACL reconstruction. We performed a PubMed search to identify and systematically evaluate outcomes of autograft and non-chemically treated non-irradiated allograft tissue in ACL reconstruction between 1980 and 2012. We included studies with Level of evidence of I to III, determinate graft treatment, a minimum of 25 patients per treatment arm, a minimum 2-year follow-up, and selected subjective and objective outcome measures. After the exclusion of 585 citations, we isolated 11 studies for further review. All patients showed improvement in clinical outcome measures and knee stability end points from injury to definitive surgical management. No statistically significant differences were detected between autografts and non-chemically processed non-irradiated allografts in Lysholm scores, International Knee Documentation Committee (IKDC) scores, Lachman examinations, pivot-shift testing, KT-1000 measurements, or failure rates. Further large-scale, well-designed studies are required to better evaluate the comparative outcomes after fresh-frozen allograft ACL reconstruction. The current study suggests that the results after autograft ACL reconstruction are comparable to those using non-chemically processed nonirradiated allograft tissue. Systematic review of Level I to III studies.

Anterior Cruciate Ligament preservation during reconstructive surgery: Does the extra surgical effort improve patient outcomes at one year?

BackgroundThe aim of this prospective cohort study was to compare patient-reported and clinical outcomes at one year post-operatively in patients who had a standard quadruple stranded hamstring tendon anterior cruciate ligament (ACL) reconstruction to those who had ACL tissue preservation with a double semitendinosus reconstruction. Materials and MethodsForty-five patients were selected for ACL preservation surgery (ACL Preserved group) and were matched by age, sex and injury acuity to 45 patients who had a standard reconstruction (ACL Reconstructed group). The primary outcome was the validated ACL-QOL score. Secondary outcomes included the IKDC Subjective and Objective assessments, clinical and instrumented laxity testing, and Tegner Activity Level. All outcomes were measured at baseline and at a minimum of one year post-operatively, by an independent qualified assessor. ResultsThe two patient groups were similar for all baseline characteristics except for a larger number of meniscal pathology in the ACL Reconstructed group. Both groups had statistically significant and clinically important improvement from baseline to one year. The ACL Preserved group showed better results for all outcomes. The ACL-QOL change score from baseline was 8.6 points (p=0.04) higher for the ACL Preserved compared to the ACL Reconstructed group. KT-2000 measurements showed a statistically significant side-to-side difference between groups. The IKDC Objective assessment reported 87% of patients with normal/nearly normal knees in the ACL Preserved group compared to 80% in the ACL Reconstructed group. ConclusionsIn patients where it is possible and feasible to preserve ACL tissue, this study suggests that the more technically demanding procedure involving ACL preservation during reconstructive surgery is worth the extra effort. The procedure provides a consistent and measurable benefit in terms of knee stability and quality of life at one year post-operative, compared to a standard hamstring reconstruction. Level of evidenceTherapeutic, prospective cohort study; Level II.

Knee Objective Stability and Isokinetic Thigh Muscle Strength after Anterior Cruciate Ligament Reconstruction: A Randomized Six-Month Follow-Up Study

Purpose: The most frequently used grafts for intra-articular anterior cruciate ligament (ACL) reconstruction are the autologous patellar tendon (PT) or doubled semitendinosus and gracilis tendons (STG) autografts. There are still controversies about graft selection for primary ACL reconstruction. Methods: A prospective, randomized study was conducted on 57 patients who underwent arthroscopically assisted ACL reconstruction between January 2010 and February 2011. In 29 patients ACL reconstruction was performed with hamstring tendon autograft (STG group), and in 28 patients the ACL reconstruction was performed with patellar tendon autograft (PT group). At 6 months follow-up, all patients have performed the isokinetic extensor and flexor muscles strength and KT-1000 measurements. Results: At 6 months after surgery, we found significantly lower average isokinetic quadriceps peak torque in the PT group compared to the STG group at angular velocity of 60°/s. However, at the same time we did not find significant difference in flexor muscle power comparing both groups. The manual maximum KT-1000 arthrometer side-to-side difference was 1.7 ± 1.7 mm for the PT group and 1.9 ± 1.6 mm for the STG group (P=0.398). No significant correlation was found between the knee objective stability (KT-1000 measurements) and the isokinetic thigh muscle strength (extensors, Spearman’s rho=0.057, P=0.671; flexors, Spearman’s rho=0.094, P=0.489). Conclusions: Both hamstring and patellar tendon autografts provided good objective stability at 6 months after surgery In addition, regardless of which graft was used, a considerable percentage of patients continue to have strength deficits. In our opinion, the ACL-reconstructed leg should have 85% or greater return to the strength of the normal leg as one criterion before release to full sports activities. We were particularly intrigued to find only half of the competitive athletes achieved this goal at 6 months after surgery.

The effect of remnant preservation on tibial tunnel enlargement in ACL reconstruction with hamstring autograft: a prospective randomized controlled trial

To investigate the effect of remnant preservation on tibial tunnel enlargement in a single-bundle anterior cruciate ligament (ACL) reconstruction with a hamstring autograft. From 2006 to 2009, a total of 62 patients who underwent single-bundle ACL reconstruction with a quadrupled hamstring tendon autograft were enrolled in this study. The patients were randomly divided into two groups: the preserving-remnant group and the removing-remnant group. Plain radiographs were taken at 1 week, and 3, 6, and 24 months postoperatively, and tibial tunnel enlargement was evaluated. The postoperative clinical assessment included the Lysholm rating scale and KT-1000 measurement. In total, 27 patients in the preserving-remnant group and 24 patients in the removing-remnant group were followed up and the median follow-up was 24.5 months (range 24-27 months). Tibial tunnel enlargement occurred within 6 months postoperatively. Positive enlargement was observed in 8 patients (29.6 %) in the preserving-remnant group and 14 patients (58.3 %) in the removing-remnant group (P = 0.0388). The percentage of tibial tunnel enlargement was 25.7 ± 6.7 and 34.0 ± 8.9 % in the preserving- and removing-remnant groups, respectively (P = 0.0004). In the preserving-remnant group, the average Lysholm score increased from 60.3 ± 5.3 (51-69) to 93.0 ± 3.5 (88-100), and the side-to-side difference of the KT-1000 changed from 6.3 ± 0.9 (5.1-8.0) to 1.4 ± 0.6 (0.5-2.4) mm. In the removing-remnant group, the average Lysholm score increased from 58.7 ± 6.5 (48-71) to 91.1 ± 3.9 (85-100), and the side-to-side difference of the KT-1000 changed from 6.5 ± 0.8 (5.4-8.2) to 1.7 ± 0.6 (0.6-2.8) mm. It is confirmed that remnant preservation in ACL reconstruction can resist tibial tunnel enlargement but that this technique does not affect the short-term clinical outcome of ACL reconstruction.

Anterior cruciate ligament reconstruction with 4-strand hamstring autograft and accelerated rehabilitation: a 10-year prospective study on clinical results, knee osteoarthritis and its predictors

Analysis of long-term clinical and radiological outcomes after anterior cruciate ligament (ACL) reconstruction with special attention to knee osteoarthritis and its predictors. A prospective, consecutive case series of 100 patients. Arthroscopic transtibial ACL reconstruction was performed using 4-strand hamstring tendon autografts with a standardized accelerated rehabilitation protocol. Analysis was performed preoperatively and 10 years postoperatively. Clinical examination included Lysholm and Tegner scores, IKDC, KT-1000 testing (MEDmetric Co., San Diego, CA, USA) and leg circumference measurements. Radiological evaluation included AP weight bearing, lateral knee, Rosenberg and sky view X-rays. Radiological classifications were according to Ahlbäck and Kellgren & Lawrence. Statistical analysis included univariate and multivariate logistic regressions. RESULTS CLINICAL OUTCOME: A significant improvement (p < 0.001) between preoperative and postoperative measurements could be demonstrated for the Lysholm and Tegner scores, IKDC patient subjective assessment, KT-1000 measurements, pivot shift test, IKDC score and one-leg hop test. A pivot shift phenomenon (glide) was still present in 43 (50%) patients and correlated with lower levels of activity (p < 0.022). Radiological outcome: At follow-up, 46 (53.5%) patients had signs of osteoarthritis (OA). In this group, 33 patients (72%) had chondral lesions (≥grade 2) at the time of ACL reconstruction. A history of medial meniscectomy before or at the time of ACL reconstruction increased the risk of knee OA 4 times (95% CI 1.41-11.5). An ICRS grade 3 at the time of ACL reconstruction increased the risk of knee OA by 5.2 times (95% CI 1.09-24.8). There was no correlation between OA and activity level (Tegner score ≥6) nor between OA and a positive pivot shift test. Transtibial ACL reconstruction with 4-strand hamstring autograft and accelerated rehabilitation restored anteroposterior knee stability. Clinical parameters and patient satisfaction improved significantly. At 10-year follow-up, radiological signs of OA were present in 53.5 % of the subjects. Risk factors for OA were meniscectomy prior to or at the time of ACL reconstruction and chondral lesions at the time of ACL reconstruction. II.

Paper 118: Is There a Correlation Between Subjective IKDC Scores and Both Pivot Shift and KT-1000 Measurements Following Anterior Cruciate Ligament Reconstruction?

Paper 118: Is There a Correlation Between Subjective IKDC Scores and Both Pivot Shift and KT-1000 Measurements Following Anterior Cruciate Ligament Reconstruction?

Tibial tunnel widening after hamstring anterior cruciate ligament reconstructions: Comparison between Rigidfix and bio-Transfix

BackgroundThere is no study comparing tibial tunnel widening after hamstring anterior cruciate ligament (ACL) reconstructions between RigidFix(r) and Bio-TransFix(r). MethodsHamstring ACL reconstructions using RigidFix(r) in 56 patients and Bio-TransFix(r) in 41 with a minimum of 2years postoperative evaluation were reviewed. Tibial fixation was performed using Intrafix in both groups. On the anterior–posterior (AP) and lateral radiographs, the diameter of the tibial tunnel was measured at proximal, middle, and distal positions. Postoperative laxity evaluations were performed using Lachman test, pivot-shift test, and instrumented laxity testing using the KT-1000 arthrometer. ResultsOn the AP and lateral radiographs, the average diameter of the tibial tunnel in the Bio-TransFix(r) group significantly increased after 6months compared to the immediate postoperative measurement (p=0.002 and p=0.002, respectively). However, the average diameter of the tibial tunnel in the RigidFix(r) group did not increase after 6months compared to the immediate postoperative measurement. Tunnel widening at 12months postoperatively in the Bio-TransFix(r) group was significantly more than that of the RigidFix(r) group on AP and lateral radiographs (p=0.012 and 0.016, respectively). Tunnel widening at 24months postoperatively showed a significant difference between the two groups (p=0.000 and 0.000, respectively). Fifteen patients (36.6%) in the Bio-TransFix(r) group and 15 patients (26.8%) in the RigidFix(r) group showed tunnel widening. There were no significant differences in results of the Lachman and pivot-shift tests, and mean KT-1000 measurement between the two groups. ConclusionThe Bio-TransFix(r) group showed progressive tibial tunnel widening after 6months postoperatively but no clinical signs of instability. Level of evidenceLevel III.

The outcomes after anterior cruciate ligament reconstruction in adolescents with open physes

We evaluated the clinical outcome of anterior cruciate ligament reconstruction (ACLR) in adolescents with open physes and compared those results with adults. Fifteen adolescents with open physes underwent physeal-sparing double-bundle ACLR using hamstring autograft. The median age of the adolescents was 14 years (range 13-16 years). Forty adults underwent anatomic double-bundle ACLR during the same period of this study. The median age of the adults was 26 years (range 17-39 years). Clinical outcomes were evaluated in terms of manual Lachman test, pivot shift test and the results of KT-2000 arthrometer. Additionally, we evaluated clinical outcome in terms of International Knee Documentation Committee (IKDC) score and Lysholm Knee Scoring Scale. We also evaluated rates of re-rupture. No clinically significant growth abnormalities were observed in adolescent cases. In the Lachman test, two of the 15 adolescents had a positive, whereas one of the 40 adults had a positive (n.s.). In the pivot shift test, three of the 15 adolescents had a positive, whereas two of the 40 adults had a positive (n.s.). There was no statistically significant difference between adolescents and adults, in the mean side-to-side difference in KT-2000 measurements (1.5 ± 1.5 mm vs. 1.1 ± 1.9 mm: n.s.), the median IKDC score (96.7 vs. 97.3: n.s.) and Lysholm Scale (99 vs. 98: n.s.), rates of re-rupture (13.3 vs. 7.5 %: n.s.). Physeal-sparing ACLR with hamstring autograft in adolescents with open physes resulted in good clinical outcomes similar to those of ACLR in adults without growth abnormalities.

Clinical Comparisons Between the Transtibial Technique and the Far Anteromedial Portal Technique for Posterolateral Femoral Tunnel Drilling in Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction

The purpose of this study was to compare the clinical results of the transtibial and far anteromedial portal techniques for posterolateral (PL) femoral tunnel drilling in double-bundle anterior cruciate ligament reconstruction. This study involved 50 patients who underwent double-bundle anterior cruciate ligament reconstruction and were followed up for more than 2 years. The anteromedial bundle was reconstructed with the far anteromedial portal technique in all patients. However, the PL bundle was reconstructed with the transtibial and far anteromedial portal techniques in 22 patients (group T) and 28 patients (group F), respectively. The follow-up visits included evaluation of Lysholm knee scores, KT-2000 measurement of anterior knee laxity (MEDmetric, San Diego, CA), the pivot-shift test, and radiography. The length of the PL femoral tunnel in group F (32.2 mm) was significantly shorter than that in group T (39.0 mm). Lateral knee radiographs showed that the positions of the EndoButtons (Smith & Nephew Endoscopy, Andover, MA) for the PL bundles were significantly more posterior (12.8 mm) and distal (3.1 mm) in group F than in group T. The mean KT-2000 side-to-side difference in group T (0.9 mm) and group F (0.7 mm) did not significantly differ. In addition, no significant difference was noted between the groups with respect to Lysholm knee scores and the pivot-shift test results. This study showed that the far anteromedial portal technique is as effective as the transtibial technique and results in good restoration of joint stability and knee scores despite shorter femoral tunnel length and inferoposterior position of the EndoButton. Level III, retrospective comparative study.

Arthroscopic anterior cruciate ligament reconstruction with remnant preservation: a prospective comparison study

To evaluate the clinical significance of arthroscopic anterior cruciate ligament (ACL) reconstruction using the remnant-preserved technique. From August 2008 to September 2009, 70 cases with the remnant of injured ACL were included in the trials, which were randomized into the remnant preservation (RP) group and the control group, 35 cases in each group. All patients in the two groups underwent arthroscopic ACL reconstruction surgeries, with ACL-remnant preserving technique in RP group and ACL-remnant resection in control group, respectively. The injured ACL was reconstructed with allograft in all cases. Postoperative follow-up assessment included the International Knee Documentation Committee (IKDC) grading and Lysholm score, Lachman test, pivot shift test and KT-1000 measurement, proprioception measurements and the arthroscopic second look evaluation. Sixty-one (61/70, 87%) cases were available for an average of 13.1 months follow-up assessment postoperatively. There were no significant differences between the RP and control group in functional outcome as evaluated with Lysholm score (96.4 vs. 94.9, P = 0.71) and IKDC grading (cases with A and B gradings: 30 vs. 29, P = 0.586). Regarding objective stability, there were no differences between the 2 group in mean side-to-side difference of KT-1000 (1.69 mm vs. 1.65 mm, P = 0.83), Lachman test (negative cases: 29 vs. 28, P = 1.00) and pivot shift test (negative cases: 31 vs. 27, P = 0.225). There was also no difference between the groups in proprioception evaluation measured with angle repetitive test (4.56° vs. 4.28°, P = 0.522). During second look arthroscopic examination, the grafts synovial coverage rates were found to be 85% in the RP group and 84.2% in the control group, without significant difference (P > 0.05). Arthroscopic ACL reconstruction with the remnant preserving technique using tendon allograft do not improve the postoperative knee-joint function scores, stability, proprioception and synovial coverage of grafts.