Increasing expectations from arthroscopic anterior cruciate ligament (ACL) reconstructions require precise knowledge of technical details such as minimum intra-femoral tunnel graft lengths. A common belief of having ≥20mm of grafts within the femoral tunnel is backed mostly by hearsay rather than scientific proof. We examined clinico-radiological outcomes in patients with intra-femoral tunnel graft lengths <20 and ≥20mm. Primary outcomes were knee scores at 1-year. Secondarily, graft revascularization was compared using magnetic resonance imaging (MRI). We hypothesized that outcomes would be independent of intra-femoral tunnel graft lengths. This prospective, single-surgeon, cohort study was conducted at a tertiary care teaching centre between 2015–2018 after obtaining ethical clearances and consents. Eligible arthroscopic ACL reconstruction patients were sequentially divided into 2 groups based on the intra-femoral tunnel graft lengths (A: < 20 mm, n = 27; and B: ≥ 20 mm, n = 25). Exclusions were made for those > 45 years of age, with chondral and/or multi-ligamentous injuries and with systemic pathologies. All patients were postoperatively examined and scored (Lysholm and modified Cincinnati scores) at 3, 6 and 12 months. Graft vascularity was assessed by signal-to-noise quotient ratio (SNQR) using MRI. Statistical significance was set at p<0.05. Age and sex-matched patients of both groups were followed to 1 year (1 dropout in each). Mean femoral and tibial tunnel diameters (P =0.225 and 0.595) were comparable. Groups A (<20mm) and B (≥20mm) had 27 and 25 patients respectively. At 3 months, 2 group A patients and 1 group B patient had grade 1 Lachman (increased at 12 months to 4 and 3 patients respectively). Pivot shift was negative in all patients. Lysholm scores at 3 and 6 months were comparable (P3= 0.195 and P6= 0.133). At 1 year both groups showed comparable Cincinnati scores. Mean ROM was satisfactory (≥130 degrees) in all but 2 patients of each group (125–130 degrees). MRI scans at 3 months and 1 year observed anatomical tunnels in all without any complications. Femoral tunnel signals in both groups showed a fall from 3–12 months indicating onset of maturation of graft at femoral tunnel. Our hypothesis, clinical and radiological outcomes would be independent of intra-tunnel graft lengths on the femoral aspect, did therefore prove correct. Intra-femoral tunnel graft lengths of <20 mm did not compromise early clinical and functional outcomes of ACL reconstructions. There seems to be no minimum length of graft within the tunnel below which suboptimal results should be expected

There has been a lot of focus on the value of anatomic tunnel placement in ACL reconstruction, and the relative merits of single and double bundle grafts. Multiple cadaveric and animal studies have compared the effects of tunnel placement and graft type on knee biomechanics. 45 patients who underwent ACL reconstruction were included into our study. Femoral tunnel position was analysed by two independent doctors using the radiographic quadrant method as described by Bernard et al., and the mean values calculated. Forty-one of these patients completed a KOOS questionnaire. The mean ratio ‘a’ was 26.57% and mean ratio ‘b’ was 30.04% as compared to 24.8% (+/− 2.2%) and 28.5% (+/− 2.5%) respectively quoted by Bernard et.al, as the ideal tunnel position. Only twenty-three of these femoral tunnels were in the anatomic range. Analysis of forty-one KOOS surveys (23 anatomic, 18 non-anatomic) revealed no significant difference in total score or subscales between the anatomic and non-anatomic groups (p= >0.05). Our study suggests that the ideal tunnel position, as described by Bernard et.al. may not be ideal and fixed

Purpose. Twelve case reports of distal femur fractures as post-operative complications after anterior cruciate ligament (ACL) reconstruction have been described in the literature. The femoral tunnel has been suggested as a potential stress riser for fracture formation. The recent increase in double bundle ACL reconstructions may compound this risk. This is the first biomechanical study to examine the stress riser effect of the femoral tunnel(s) after ACL reconstruction. The hypotheses tested in this study are that the femoral tunnel acts as a stress riser to fracture and that this effect increases with the size of the tunnel (8mm versus 10mm) and with the number of tunnels (one versus two). Method. Femoral tunnels simulating single bundle (SB) hamstring graft (8 mm), bone-patellar tendon-bone graft (10 mm), and double bundle (DB) ACL reconstruction (7mm, 6 mm) were drilled in fourth generation saw bones. These three experimental groups and a control group consisting of native saw bones without tunnels, were loaded to failure. Result. All fractures occurred through the tunnels in the double tunnel group whereas fractures did not consistently occur through the tunnels in the single tunnel groups. The mean fracture load was 6145 N 471 N in the native group, 5691 N 198 N in the 8 mm single tunnel group, 5702 N 282 N in the 10 mm single tunnel group, and 4744 N 418 N in the double tunnel group. The mean fracture load for the double tunnel group was significantly different when compared to native, 8 mm single bundle, and 10 mm single bundle groups independently (p value = 0.0016, 0.0060, and 0.0038 respectively). No other statistically significant differences were identified. Conclusion. An anatomically placed femoral tunnel in single bundle ACL reconstruction in our experimental model was not a stress riser to fracture, whereas the two femoral tunnels in double bundle ACL reconstruction significantly decreased load to failure. The results support the sparcity of reported peri-ACL reconstruction femur fractures in single femoral tunnel techniques. However, the increased fracture risk in double bundle ACL reconstruction is a cause for concern and may impact patient selection

Background. Recent publications have supported the anatomic placement of anterior cruciate grafts to optimise knee function. However, anatomic placement using the anteromedial portal has been shown to have a higher failure rate than traditional graft placement using the transtibial method. This is possibly due to it being more technically difficult and to the short femoral tunnel compromising fixation methods. It also requires the knee to be in hyper flexion. This position is not feasible during with a tourniquet in situ on the heavily muscled thighs of some athletes. Hypothesis: That navigation can be used to place the femoral tunnel in the anatomic position via a more medial transtibial tunnel. Methods. 25 patients underwent Navigated Anterior Cruciate reconstruction with quadruple hamstring grafts. The Orthopilot™ 3.0 ACL (BBraun Aesculap, Tuttlingen) software was used. The femoral and tibial ACL footprints were marked on the bones with a radio frequency probe and registered. The pivot shift test, anterior drawer and internal and external rotation were registered. A navigated tibial guide wire was inserted at 25° to the sagittal plane and 45° to the transverse plane exiting through the centre of the tibial footprint. The guide wire was advanced into the joint to just clear of the surface of the femoral footprint with the knee in 90° flexion. Flexion/extension of the knee was done to determine the closest position of the guide wire tip to the centre of the anatomical femoral footprint. If the tip was within 2mm of the centre of footprint, the position was accepted. If not the tibial guide wire was repositioned and the process repeated. The tibial tunnel was drilled, followed by transtibial drilling of the femoral tunnel. A screen shot was done to allow determination of the shape and area of the tunnel aperture relative to the femoral footprint using ImageJ (National Institute of Health). The graft was fixed proximally with an Arthrex ACL Tightrope® and distally with a Genesys™ interference screw. The pivot shift test, anterior drawer and internal and external rotation were repeated and recorded using the software. Results. In 22 out of 25 patients the centre of the drill hole was within 2mm of the centre of the anatomic femoral footprint. In 3 patients it was between 2 and 4 mm off centre. The femoral tunnel diameter ranged from 7.5mm to 9.5mm. In 23 knees there was more than 80 % overlap between the tunnel aperture and the anatomical footprint. In the other 2 knees there was 65% and 75% overlap respectively. The direction of the final tibial tunnel ranged from 22° to 28° from the sagittal plane and 42° to 49° from the transverse plane. The optimum knee flexion was between 76° and 94°. In all cases, the pivot shift recorded by the software was absent after graft fixation. There was a statistically significant difference between the anterior drawer, internal and external rotation before and after graft fixation (p<0.05). Conclusion. Based on our data, navigation allows reproducible transtibial anatomic placement of the quadruple hamstring ACL graft. This is possible when the position of the tibial tunnel is customised to the anatomy of the individual patient's knee

Medial portal reaming may allow for the creation of a more anatomically positioned femoral tunnel during Anterior Cruciate Ligament (ACL) reconstruction. However, this technique also results in a shorter tunnel which may make fixation difficult. The purpose of this study is to determine the average length of a femoral tunnel created using a medial portal technique and to correlate this with patient gender, height and Body Mass Index (BMI). Fifty-four consecutive patients underwent ACL reconstruction with a femoral tunnel created using a medial portal technique. The tunnels were created using a spade tip guide pin (Arthrex, Naples, FL) with the goal of creating the tunnel in the 2-2:30 o'clock position (left knee) or 9:30-10 o'clock position (right knee). The total osseous length of the femur (TOL) was measured using a depth gauge. Descriptive statistics of the TOL were calculated and bivariate correlation coefficients (Pearson r) were calculated to determine the relationship between TOL and patient height and weight. The mean TOL was found to be 33.77 ± 5.27 mm (24-50 mm). TOL was found to correlate with patient height (r=0.32, r. 2. =0.10, p=0.04) and was not correlated to weight (r=0.24, r. 2. =0.06, p=0.15) or BMI (r=0.06, r. 2. =0.004, p=0.7). Men had a greater TOL (34.91 ± 5.4) than women (32.13 ± 4.80) but this difference was not found to be statistically significant (p=0.10). ACL reconstruction using a medial portal yields a mean total osseous length of 33.77 mm. This length is significantly correlated with patient height. ACL reconstruction using a medial portal approach to femoral reaming can lead to tunnels as short as 24 mm. Patient height may be a useful clinical tool to indicate the potential for a short femoral tunnel

Introduction. The transtibial approach is widely used for femoral tunnel positioning in ACL reconstruction. Controversy exists over the superiority of this approach over others. Few studies reflected on the reproducibility rates of the femoral tunnel position in relation to the approach used. Methods. We reviewed AP and Lat X-ray radiographs post isolated ACL reconstruction for 180 patients for femoral tunnel position, tibial tunnel position and graft inclination angle. All patients had their operations performed by one surgeon in one hospital between March 2006 and Sep 2010. All operations were performed using one standard technique using transtibial approach for femoral tunnel positioning. Two orthopaedic fellows, with similar experiences, reviewed blinded radiographs. A second reading was done 8 weeks later. Pearson inter-observer and intra-observer correlation analyses were done using SPSS. Mean age was 29 years (range 16–54). Results. Pearson intra-observer correlation shows substantial to perfect agreement while Pearson's inter-observer correlation shows moderate to substantial agreement. Previous literature proved that optimal femoral tunnel position for the best clinical and biomechanical outcome is for the centre of the tunnel to be at 43% from the lateral end of the width of the femoral condyles on the AP view and at 86% from the anterior end of the Blumensaat's line on the lateral view. In our study 85% of the femoral tunnels were within +/− 5% of the optimal tunnel position on the AP views (43%), and more than 70% of the femoral tunnels were within +/−5% of the optimal tunnel position on the Lateral view (86%). Conclusion. Based on our results we concluded that using one standardised transtibial technique for ACL reconstruction can result in high reproducibility rates of optimal femoral tunnel position. Further studies are needed to validate our results and to study the reproducibility rates for different approaches and techniques

The transtibial approach is widely used for femoral tunnel positioning in ACL reconstruction. Controversy exists over the superiority of this approach over others. Few studies reflected on the reproducibility rates of the femoral tunnel position in relation to the approach used. We reviewed AP and Lat X-ray radiographs post isolated ACL reconstruction for 180 patients for femoral tunnel position, tibial tunnel position and graft inclination angle. All patients had their operations performed by one surgeon in one hospital between March 2006 and Sep 2010. All operations were performed using one standard technique using transtibial approach for femoral tunnel positioning. Two orthopaedic fellows, with similar experiences, reviewed blinded radiographs. A second reading was done 8 weeks later. Pearson inter-observer, intra-observer correlation and Bland-Altman agreements plots statistical analyses were done. Mean age was 29 years (range 16–54), Pearson intra-observer correlation shows substantial to perfect agreement while Pearson's inter-observer correlation shows moderate to substantial agreement. Previous literature proved that optimal femoral tunnel position for the best clinical and biomechanical outcome is for the centre of the tunnel to be at 43% from the lateral end of the width of the femoral condyles on the AP view and at 86% from the anterior end of the Blumensaat's line on the lateral view. In our study 85% of the femoral tunnels were within +/− 5% of the optimal tunnel position on the AP views, and more than 70% of the femoral tunnels were within +/−5% of the optimal tunnel position on the Lateral view. Interobserver and intraobserver corelations show moderate to substantial agreement, Bland-Altman agreement plots show substantial agreements for interobserver and intraobserver measurements. These results were found to be statistically significant at 0.01. Based on our results we conclude that using one standardised transtibial technique for ACL reconstruction can result in high reproducibility rates of optimal femoral tunnel position. Further studies are needed to validate our results and to study the reproducibility rates for different approaches and techniques

Aim. The aim of this study is to outline the steps and techniques required to create a patient specific 3D printed guide for the accurate placement of the origin of the femoral tunnel for single bundle ACL reconstruction. Introduction. Placements of the femoral tunnels for ACL reconstruction have changed over the years 1,2. Most recently there has been a trend towards placing the tunnels in a more anatomic position. There has been subsequent debate as to where this anatomic position should be 3. The problem with any attempt at consensus over the placement of an anatomic landmark is that each patient has some variation in their positioning and therefore a fixed point for all has compromise for all, as it is an average 4. Our aim was to attempt to make a cost effective and quick custom guide that could allow placement of the center of the patients’ newly created femoral tunnel in the mid position of their contralateral native ACL femoral footprint. Materials & Methods. We took a standard protocol MRI scan of a patient's knee without ACL injury transferred the DICOM files to a personal computer running OsiriX (Pixmeo, Geneva, Switzerland.) and analyzed it for a series of specific anatomical landmarks (fig1). These measurements and points were then utilized to create a 3D computer aided design (CAD) model of a custom guide. This was done using the 3D CAD program 123Design (Autodesk Ltd., Farnbourgh, Hampshire). This 3D model was then uploaded to an online 3D printing service and the physical guide was created in transparent acrylic based photopolymer, PA220 plastic (fig 2) and 316L stainless steel. The models created were then measured using vernier calipers to confirm the accuracy of the final guides. The models produced were accurate with no statistical difference in size and positioning of the center of the ACL footprint from the original computer model and to the position of the ACL from the MRI scans. The costs for the models 3D printed were £3.50 for the PA220 plastic, £15 for the transparent photopolymer and £25 for the 316L stainless steel. The time taken from MRI to delivery for the physical models was 7 days. Conclusion. This study serves as the first step and a proof of concept for the accurate creation of patient specific 3D printed guides for the anatomical placement of the femoral tunnel for ACL reconstruction. The guides were easy to create and produce taking only a week and with a cost of between £3.50 and £25

Anterior cruciate ligament (ACL) injuries are one of the most common ligament injury occurring in young and active individuals. Reconstruction of the torn ligament is the current standard of care. Of the many factors which determine the surgical outcome, fixation of the graft in the bony tunnels has significant role. This study compared the clinical and functional outcome in patients who underwent ACL reconstruction by standard anteromedial portal technique with single bundle hamstring graft anchored in the femoral tunnel using rigidfix and cortical button with adjustable loops. The tibial fixation and rehabilitation protocol were same in both groups. 107 patients underwent ACL reconstruction over a two-year period (87 males, 20 females, 44 after motor vehicle accident, 34 after sports injuries, 79 isolated ACL tear, 21 associated medial meniscus tear, 16 lateral meniscus tear and 11 both menisci). Rigid fix group had 47 patients and adjustable loop 60 patients. Clinical evaluation at end of one year showed better stability in rigid fix group regarding Lachman, anterior drawer, pivot shift tests, KT 1000 arthrometer side to side difference and hop limb symmetry index. However, the differences were not statistically significant. Functional evaluation using IKDC 2000 subjective score and Lysholm score showed better results in rigidfix group than variable loop, but was not statistically significant. However, lower scores were noted in patients with concomitant meniscal injury than in isolated acl tear patients and this was statistically significant in both groups. Rigidfix seems to give better graft fixation on femoral side than variable loop, but by the end of one year the functional outcome is comparable in isolated acl reconstructions

The purpose of this study was to determine the incidence of graft-tunnel mismatch (GTM) when performing anatomic anterior cruciate ligament reconstruction (ACLR) using bone-patella tendon-bone (BPTB) grafts and anteromedial portal drilling. Beginning in November 2018, 100 consecutive patients who underwent ACLR by two sports fellowship-trained, orthopedic surgeons using BPTB autograft and anteromedial portal drilling were prospectively identified. The BPTB graft dimensions and the femoral tunnel distance, tibial tunnel distance, intra-articular distance, and total distance were measured. Surgeons determined the depth and angle of tunnels based on the patella tendon graft length dimensions in each case. After passage of the graft, the distance from the distal graft tip to the tibial cortex aperture was measured. GTM was defined as the need for additional measures to obtain satisfactory tibial graft fixation (< 1 5e20 mm of bone fixation). The incidence of mismatch was 6/100 (6%). Five cases involved the graft being too long, with the tibial bone plug protruding excessively from the tibial tunneld4/5 had a patella tendon length ? 50 mm. Three cases were managed with femoral tunnel recession, and two were treated with a free bone plug technique. One patient with a patella tendon length of 35 mm had a graft that was too short, with the tibial bone plug recessed in the tibial tunnel. Of patients whose tibial tunnel distance was within 5 mm of the patella tendon length, only 1/46 (2%) patients had mismatch, whereas 5/54 (9%) of patients who had >5 mm difference had mismatch. The incidence of grafttunnel mismatch after anatomic ACLR using BTPB and anteromedial portal drilling in this study is 6%. To limit the occurrence of GTM where the graft is too long, surgeons should drill tibial tunnel distances within 5 mm of the patella tendon length

Arthrofibrosis is a less common complication following anterior cruciate ligament (ACL) reconstruction and there are concerns that undergoing early surgery may be associated with arthrofibrosis. The aim of this study was to identify the patient and surgical risk factors for arthrofibrosis following primary ACL reconstruction. Primary ACL reconstructions prospectively recorded in the New Zealand ACL Registry between April 2014 and December 2019 were analyzed. The Accident Compensation Corporation (ACC) database was used to identify patients who underwent a subsequent reoperation with review of operation notes to identify those who had a reoperation for “arthrofibrosis” or “stiffness”. Univariate Chi-Square test and multivariate Cox regression analysis was performed. Hazard ratios (HR) with 95% confidence intervals (CI) were computed to identify the risk factors for arthrofibrosis. 9617 primary ACL reconstructions were analyzed, of which 215 patients underwent a subsequent reoperation for arthrofibrosis (2.2%). A higher risk of arthrofibrosis was observed in female patients (adjusted HR = 1.67, 95% CI 1.22 – 2.27, p = 0.001), patients with a history of previous knee surgery (adjusted HR = 1.97, 95% CI 1.11 – 3.50, p = 0.021) and when a transtibial femoral tunnel drilling technique was used (adjusted HR = 1.55, 95% CI 1.06 – 2.28, p = 0.024). Patients who underwent early ACL reconstruction within 6 weeks of their injury did not have a higher risk of arthrofibrosis when compared to patients who underwent surgery more than 6 weeks after their injury (3.5% versus 2.1%, adjusted HR = 1.56, 95% CI 0.97 – 2.50, p = 0.07). Age, graft type and concomitant meniscal injury did not influence the rate of arthrofibrosis. Female sex, a history of previous knee surgery and a transtibial femoral tunnel drilling technique are risk factors for arthrofibrosis following primary ACL reconstruction

Anatomic all-inside ACL reconstruction using TransLateral technique is a relatively new technique that reduces surgical invasion and pain leading to early recovery. We evaluated clinical outcomes of patients undergoing primary anatomic all-inside ACL reconstruction using TransLateral technique. Retrospective case-series evaluating patients undergoing surgery from June 2013 – December 2017. Patients were followed up clinically and using PROMS including EQ-5D, KOOS, IKDC and Tegner scores. Paired two-tailed student t-tests were used to assess clinical significance. 138 patients were included (115 males, 23 females). Mean age was 30 years (range 16.0 – 60.2). Graft choice included isolated semitendinosus (n=115) or both semitendinosus and gracilis (n=26). Mean graft length and diameter were 62.1mm and 8.7mm. Sixteen cases (11.3%) returned to theatre; MUA for arthrofibrosis (n=4), infection (n=2), haemarthrosis (n=1) and metalwork failure (n=1). Incidence of graft re-rupture was 5.7% (n=8); 7 cases were in the mid-bundle femoral tunnel placement. 52.5% (n=74) had complete peri-operative PROMS scores. Mean peri-operative EQ-5D VAS scores were 69.8 and 78.2 (p=0.02). Mean peri-operative KOOS scores for all domains demonstrated significant improvements (p<0.001). Mean peri-operative IKDC scores were 46.1 and 72.5 (p<0.05) and peri-operative Tegner activity scores were 3.3 and 5.3 (p<0.001). Anatomic all-inside ACL reconstruction using TransLateral technique demonstrates favourable clinical and biomechanical advantages including independent anatomic femoral tunnel placement, bone preservation and use of single tendon graft. Patients report significant improvements in pain, functional outcome, quality of life and return to sports. Mid-bundle femoral tunnel placement has been abandoned due to higher failure rate

Abstract. Background. The gold standard treatment for Anterior Cruciate Ligament injury is reconstruction (ACL-R). Graft failure is the concern and ensuring a durable initial graft with rapid integration is crucial. Graft augmentation with implantable devices (internal brace reinforcement) is a technique purported to reduce the risk of rupture and hasten recovery. We aim to compare the short-term outcome of ACL-R using augmented hamstring tendon autografts (internally braced with neoligament) and non-augmented hamstring autografts. Methods. This was a retrospective cohort study comparing augmented and non-augmented ACL-R. All procedures were performed in a single centre using the same technique. The Knee injury and Osteoarthritis Outcome Score [KOOS] was used to assess patient-reported outcomes. Results. There were 70 patients in the augmented and 111 patients in the control group. Mean graft diameter in the augmented group was 8.82mm versus 8.44mm in the non-augmented. Six strand graft was achievable in 73.5% of the augmented group compared to 33% in the non-augmented group. Two graft failures were reported in the non-augmented group and none in the augmented group. Patient satisfaction rates were higher in the augmented group. There was a statistically insignificant improvement in the postoperative KOOS in the augmented group compared to the non-augmented group (p 0.6). Irrespective of augmentation status, no correlation was found between the functional score and age, or femoral tunnel width. Conclusion. Augmented ACL-R may achieve superior graft diameters, lower failure rates and better patient reported outcomes when compared to nonaugmented ACL-R. Prospective trials are needed to examine this further

Meniscal repairs are commonly performed during anterior cruciate ligament (ACL) reconstruction. This study aimed to identify the risk factors for meniscal repair failure following concurrent primary ACL reconstruction. Primary ACL reconstructions with a concurrent repair of a meniscal tear recorded in the New Zealand ACL Registry between April 2014 and December 2018 were analyzed. Meniscal repair failure was defined as a patient who underwent subsequent meniscectomy, and was identified after cross-referencing data from the ACL Registry with the national database of the Accident Compensation Corporation (ACC). Multivariate Cox regression was performed to produce hazard ratios (HR) with 95% confidence intervals (CI) to identify the patient and surgical risk factors for meniscal repair failure. 2041 meniscal repairs were analyzed (medial = 1235 and lateral = 806). The overall failure rate was 9.4% (n = 192). Failure occurred in 11.1% of medial (137/1235) and 6.8% of lateral (55/806) meniscal repairs. The risk of medial failure was higher with hamstring tendon autografts (adjusted HR = 2.00, 95% CI 1.23 – 3.26, p = 0.006) and in patients with cartilage injury in the medial compartment (adjusted HR = 1.56, 95% CI 1.09 – 2.23, p = 0.015). The risk of lateral failure was higher when the procedure was performed by a surgeon with an annual case volume of less than 30 ACL reconstructions (adjusted HR = 1.92, 95% CI 1.10 – 3.33, p = 0.021). Age, gender, time from injury-to-surgery and femoral tunnel drilling technique did not influence the risk of meniscal repair failure. When repairing a meniscal tear during ACL reconstruction, the use of a hamstring tendon autograft or the presence of cartilage injury in the medial compartment increases the risk of medial meniscal repair failure. Lower surgeon case volume increases the risk of lateral meniscal repair failure

Evaluate precisely and reproducibly tridimensional positioning of bone tunnels in anterior cruciate ligament reconstructions (ACL). To propose biplanar stereoradiographic imaging as a new reference in tridimensional evaluation of ACL reconstruction (ACLR). Comparing knee 3D models issued from EOStm low-irradiation biplanar X-Ray with those issued from computed tomography (CT-Scan) high definition images will allow a bone morphological description of a previously unseen precision. We carried out the transfer of 3D models from EOStm X-Ray images obtained from 10 patients in the same reference frame with models issued from CT-Scan. Two evaluators reconstructed both pre-operative and post-operative knees, using two different stereoradiographic projections, for a total of 144 knee 3D models from EOStm. A surface analysis by distance mapping allowed us to know the differences or errors between the homologous points of the EOStm and CT reconstructions, the latter being our “bronze-standard”. At the femur, we obtained a mean (95% confidence level) error of 1.5 mm (1.3–1.6) between the EOStm models compared to the Arthro-CT segmentations when using AP-LAT incidences, compared to 1 mm (1.0 – 1.1) with oblique projections. For the tunnels placement analysis, the total radius difference between EOStm and Arthro-CT's femoral tunnel apertures was 0.8 mm (0.4–1.2) in AP-LAT and 0.6 mm (0.0–1.2) in oblique views. These femoral apertures positioning on EOStm models were within 4.3 mm (3.0–5.7) of their homologues on CT-Scan models, 4.6 mm (3.5–5.6) with the oblique views. Furthermore, 9.3o (7.2–11.4) of difference in direction between femoral tunnels from EOStm models and CT reconstructions is obtained with AP-LAT projections, 8.3o (6.6–10) with obliques views. Measures of these parameters were also performed at the tibia. According to the intra and inter-reproducibility analysis of our knee 3D models, EOStm biplanar X-Ray images prove to be fast, efficient and precise in the design of ACLR 3D models with respect to CT-Scan. Our results also propose the recourse of oblique stereoradiographic projections for the realization of knee 3D models. These models will be subjects of further analysis and will allow us eventually to propose a new frame of reference guiding the positioning of the tunnels in the ACLR

The purpose of the study was to compare prospectively and randomly two ACL reconstruction single bundle techniques, one referred to as traditional and the other referred to as anatomical, where the coronal angulation of the femoral tunnel aimed a more horizontal position at 2 and 10 o'clock. Orthopilot® System (Aesculap, Tuttlingen, Germany) was used to assist tunnel positioning in order to obtain and register translational and rotational stability. Eighteen patients (14 men and 4 women), average age 33.8 years (range 18 to 49), with isolated ACL lesion were randomized in two groups, A (Conventional) and B (Anatomical). All patients were submitted to ACL navigated arthroscopic reconstruction with quadruple hamstrings grafts. Anteromedial portal access for femoral tunnel drilling was used in all patients. The tibial and femoral tunnels drillings were monitored by the Aesculap® Orthopilot Navigation System. In Group A, the femoral tunnel positioning aimed isometricity. In Group B, femoral tunnel was drilled at 25% of Blumensaat's line length from the posterior cortex, and 30° orientation in coronal plane. Initial and final Maximum Anterior tibial Displacement (MATD), Internal Tibial Rotation (ITR) and External Tibial Rotation (ETR) at 30° knee flexion data were recorded intra operatively by the navigation system. No horizontal or rotational stability differences were found for MATD (p = 0.68), ITR (p = 014) and ETR (0.13). This study did not support the hypothesis that a more anatomical positioning leads to better rotational or anterior stability

Bioabsorbable screws for anterior cruciate ligament reconstruction (ACLR) have been shown to be associated with femoral tunnel widening and cyst formation. To compare a poly-L-lactide–hydroxyapatite screw (PLLA-HA) with a titanium screw with respect to clinical and radiological outcomes over a 5 year period. 40 patients were equally randomized into 2 groups (PLLA-HA vs titanium) and ACLR performed with a 4 strand hamstring graft with femoral tunnel drilling via the anteromedial portal. Evaluation at 2 and 5 years was performed using the International Knee Documentation Committee assessment (IKDC), Lysholm knee score, KT 1000 arthrometer, single-legged hop test. Magnetic resonance imaging was used to evaluate tunnel and screw volume, ossification around the screws, graft integration and cyst formation. There was no difference in any clinical outcome measure at 2 or 5 years between the 2 groups. At 2 years, the PLLA-HA femoral tunnel was significantly smaller than the titanium screw tunnel (p=0.015) and at 5 years, there was no difference. At 2 years the femoral PLLA-HA screw was a mean 76% of its original volume and by 5 years, 36%. At 2 years the tibial PLLA-HA screw mean volume was 68% of its original volume and by 5 years, 46%. At 5 years, 88% of femoral tunnels and 56% of tibial tunnels demonstrated a significant ossification response. There was no increase in cyst formation in the PLLA-HA group and no screw breakages. The PLLA-HA screw provides adequate aperture fixation in ACLR with excellent functional outcomes. It was not associated with femoral tunnel widening or increased cyst formation when compared with the titanium screw. The resorbtion characteristics appear favourable and the hydroxyapatite component of the screw may stimulate osteoconduction, contributing to these results. The PLLA-HA screw is a good alternative to a titanium screw in ACLR, which may aid revision procedures and allow for imaging without artifact

Introduction. Transportal technique of femoral drilling allows the femoral tunnel to be placed in anatomic location. The study was conducted to evaluate the orientation of ACL graft performed by two different techniques and compared to orientation of native ACL. Materials/Methods. 50 patients (Group A) underwent ACL reconstruction with transtibial technique using transfix on the femoral side and 30 patients (Group B) underwent ACL reconstruction with transportal technique using endobutton. We used quadrupled hamstrings graft and tibial fixation was achieved with bio-absorbable screws. All patients were evaluated with 3 Tesla MRI at 6 months post-operatively and femoral tunnel angle in coronal plane (FTA), tibial tunnel angle (TTA) in sagittal plane, graft angle in coronal plane (GA coronal), graft angle in sagittal plane (GA sagittal), and graft- Blumensaat line angle (GBLA) were measured. A control group of patients (Group C, n=50)was also included to evaluate the orientation of native ACL. Results. The femoral tunnel angle (FTA) was significantly lower in group B as compared to group A, 54.03±5.05 vs 71.6±6.02, p<0.05. The tibial tunnel angle (TTA) was similar in group A and B, 65±5.2 vs. 62.9±4.5, p>0.05. Graft angle in coronal plane (GA coronal) was significantly lower in group B when compared to group A, 62.4±5.6 vs 72.5±5.5, p<0.05, and there was no significant difference between group B and C. Similarly graft angle in sagittal plane (GA sagittal) in group B was found to be significantly lower as compared to group A and similar to group C, 51.2±4.3 vs 65.3±3.6, p<0.05. The graft-Blumensaat line angle (GBLA) was significantly lower in group B as compared to Group A, 8.6±1.4 vs 13.5±1.2, p<0.05. Conclusions. The orientation of the reconstructed ligament was found to be closer to the native ACL in transportal technique of femoral drilling

Transportal technique of femoral drilling allows the femoral tunnel to be placed in anatomic location. The study was conducted to evaluate the orientation of ACL graft performed by two different techniques and compared to orientation of native ACL. 50 patients (Group A) underwent ACL reconstruction with transtibial technique using transfix on the femoral side and 30 patients (Group B) underwent ACL reconstruction with transportal technique using endobutton. We used quadrupled hamstrings graft and tibial fixation was achieved with bioabsorbable screws. All patients were evaluated with 3 Tesla MRI at 6 months post-operatively and femoral tunnel angle in coronal plane (FTA), tibial tunnel angle (TTA) in sagittal plane, graft angle in coronal plane (GA coronal), graft angle in sagittal plane (GA sagittal), and graft-Blumensaat line angle (GBLA) were measured. A control group of patients (Group C, n=50)was also included to evaluate the orientation of native ACL. The femoral tunnel angle (FTA) was significantly lower in group B as compared to group A, 54.03±5.05 vs 71.6±6.02, p<0.05. The tibial tunnel angle (TTA) was similar in group A and B, 65±5.2 vs. 62.9±4.5, p>0.05. Graft angle in coronal plane (GA coronal) was significantly lower in group B when compared to group A, 62.4±5.6 vs 72.5±5.5, p<0.05, and there was no significant difference between group B and C. Similarly graft angle in sagittal plane (GA sagittal) in group B was found to be significantly lower as compared to group A and similar to group C, 51.2±4.3 vs 65.3±3.6, p<0.05. The graft-Blumensaat line angle (GBLA) was significantly lower in group B as compared to Group A, 8.6±1.4 vs 13.5±1.2, p<0.05. The orientation of the reconstructed ligament was found to be closer to the native ACL in transportal technique of femoral drilling

Over the last two decades, anatomic anterior cruciate ligament (ACL) reconstructions have gained popularity, while the use of extraarticular reconstructions has decreased. However, the biomechanical rationale behind the lateral extraarticular sling has not been adequately studied. By understanding its effect on knee stability, it may be possible to identify specific situations in which lateral extraarticular tenodesis may be advantageous. The primary objective of this study was to quantify the ability of a lateral extraarticular sling to restore native kinematics to the ACL deficient knee, with and without combined intraarticular anatomic ACL reconstruction. Additionally, we aimed to characterise the isometry of four possible femoral tunnel positions for the lateral extraarticular sling. Eight fresh frozen hip-to-toe cadavers were used in this study. Navigated Lachman and mechanised pivot shift examinations were performed on ACL itact and deficient knees. Three reconstruction strategies were evaluated: Single bundle anatomic intraarticular ACL reconstruction, Lateral extraarticular sling, Combined intraarticular ACL reconstruction and lateral extraarticular sling. After all stability tests were completed, we quantified the isometry of four possible femoral tunnel positions for the lateral extraarticular sling using the Surgetics navigation system. A single tibial tunnel position was identified and digitised over Gerdy's tubercle. Four possible graft positions were identified on the lateral femoral condyle: the top of the lateral collateral ligament (LCL); the top of the septum; the ideal tunnel position, as defined by the navigation system's own algorithm; and the actual tunnel position used during testing, described in the literature as the intersection of the linear projections of the LCL and the septum over the lateral femoral condyle. For each of the four tunnel positions, the knee was cycled from 0 to 90® of flexion and fiber length was recorded at 30® intervals, therefore quantiying the magnitude of anisometry for each tunnel position. Stability testing: Sectioning of the ACL resulted in an increase in Lachman (15mm, p = 0.01) and mechanised pivot shift examination (6.75mm, p = 0.04) in all specimens compared with the intact knee. Anatomic intraarticular ACL reconstruction restored the Lachman (6.7mm, p = 3.76) and pivot shift (−3.5mm, p = 0.85) to the intact state. With lateral extraarticular sling alone, there was a trend towards increased anterior translation with the Lachman test (9.2mm, p = 0.50). This reconstruction restored the pivot shift to the intact state. (1.25mm, p = 0.73). Combined intraarticular and extraarticular reconstruction restored the Lachman (6.2mm, p = 2.11) and pivot shift (−3.75mm, p = 0.41) to the intact state. There was no significant difference between intraarticular alone and combined intraarticular and extraarticular reconstruction. (p = 1.88). Isometry: The ideal tunnel position calculated by the navigation system was identified over the lateral femoral condyle, beneath the mid-portion of the LCL. The anisometry for the ideal tunnel position was significantly lower (5.9mm; SD = 1.8mm; P<0.05) than the anisometry of the actual graft position (14.9mm; SD = 4mm), the top of the LCL (13.9mm; SD = 4.3mm) and the top of the septum (12mm; SD = 2.4mm). In the isolated acute ACL deficient knee, the addition of a lateral extraarticular sling to anatomic intraarticular ACL reconstruction provides little biomechanical advantage and is not routinely recommended. Isolated lateral extraarticular sling does control the pivot shift, and may be an option in the revision setting or in the lower demand patient with functional instability. Additionally, the location of the femoral tunnel traditionally used results in a significantly more anisometric graft than the navigation's system mathematical ideal location. However, the location of this ideal tunnel placement lies beneath mid-portion of the fibers of the LCL, which would not be clinically feasible