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Background: The development of less invasive all‐inside techniques regarding anterior cruciate ligament (ACL) reconstruction surgery has been associated with various advantages, including fewer complications and reduced postoperative pain. Silva et al. described a quadruple semitendinosus graft construct and suspensory button fixation for ACL reconstruction as an alternative technique. At the end of this technique, the tibial tunnel is filled with a bone autograft plug. This paper aims to examine the incorporation of the autograft and thus evaluate whether the "Silva technique" provides the same benefits as all‐inside techniques. Methods: A prospective study assessed 31 patients undergoing ACL reconstruction surgery using the "Silva technique." The cases involved in the study were skeletally mature patients with no previous history of ACL surgery or multiligamentous instability. All patients followed the same rehabilitation program and were examined at three standardized follow‐up visits: 4 months, 8 months, and 1 year postoperatively. Tegner–Lysholm knee score (TLKS), visual analog score (VAS) for pain, and the IKDC subjective knee score were completed at every visit. A knee MRI scan was performed at every scheduled visit to assess bone graft incorporation and remodeling. Results: TLKS scores revealed a considerable improvement compared to preoperative figures, from 57.2 points preoperatively to an average of 99.4 at the 12‐month follow‐up (p < 0.0001). VAS scores were substantially ameliorated after the operation and until the second follow‐up visit, from 5 before surgery to zero 8 months after the operation, with no noteworthy alterations afterward (p < 0.0001). IKDC subjective knee score outcomes were found to have increased at the last follow‐up, from 59.3 prior to surgery to 99.8 12 months postoperatively (p < 0.0001). Regarding the MRI features of the bone autograft, the tibial tunnel was entirely filled by bone formation at the last MRI scan, suggesting complete integration of the autograft in all patients. Conclusions: Bone autograft employed to seal the tibial tunnel was completely incorporated in all cases 1 year postoperatively. The "Silva technique" appears to feature all the avails of all‐inside techniques, whilst it seems to be simpler and easier than them after the surgeon is familiarized with its particular aspects. It is a robust option in orthopedic surgeons' arsenal. However, further large‐scale pertinent research is requisite to confirm the findings of this study. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the association between the progression of medial joint space (MJS) narrowing, medial meniscus extrusion (MME) and clinical scores and the tibial tunnel position in pullout repairs for medial meniscus posterior root tears (MMPRTs). Methods: This retrospective study examined 54 patients. Changes in MJS (ΔMJS), MME (ΔMME) and clinical scores and their relationship with the tibial tunnel position were evaluated using correlation coefficients. The distance from the anatomical to technical attachment position in the tibial tunnel position was measured in the anterior and medial directions, and the direct distance was measured using the Pythagorean theorem. Results: The mean ΔMJS and ΔMME were 0.6 ± 0.8 and 1.3 ± 1.3 mm, respectively, and the mean anterior, medial and direct distances were 1.4 ± 2.3, 2.2 ± 1.7 and 3.4 ± 1.7 mm, respectively. ΔMJS had a significant positive correlation with the medial (r = 0.580, p < 0.001) and direct (r = 0.559, p < 0.001) distances, while ΔMME had a significant positive correlation with direct distance (r = 0.295, p = 0.030). Several clinical scores were significantly negatively correlated with these distances. Conclusion: In transtibial pullout repair for MMPRTs, accurate tibial tunnel position delayed the progression of MJS narrowing and MME, leading to improved clinical outcomes. The progression of MJS narrowing was associated with the mediolateral direction of the tibial tunnel position, while the clinical scores were associated with the anteroposterior direction of the tibial tunnel position. These findings indicate the need to orient the tip of the guide in a more posterolateral direction when creating the tibial tunnel. Level of Evidence: Level IV. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the validity of using tibial capsular reflection and septum in the posterior compartment as landmark during posterior cruciate ligament (PCL) reconstruction (PCLR). Methods: Anatomic measurements were obtained for 12 fresh human cadaveric knee specimens to observe the spatial position of the tibial insertion of the PCL in relation to the posterior septum and the capsular reflection in the posterior compartment. Sixty patients who underwent reconstruction of the PCL between 2020 and 2023 were also retrospectively investigated. The tibial tunnel was replaced in all patients using the same method (with reference to the tibial capsular reflection and the posterior septum). The placement of the tibial tunnel was assessed using X‐ray fluoroscopy intraoperatively and computed tomography and three‐dimensional reconstruction postoperatively. Results: All fibres in the tibial insertion of the PCL in the 12 cadaveric specimens were located in the posteromedial compartment, adjacent to the posterior septum. The inferior border of the PCL insertion is adjacent to the tibial capsular reflection, which is attached at the champagne glass drop‐off of the posterior tibia. In our previous cases, none of the patients experienced postoperative or intraoperative complications such as neurovascular injury, and the angle between the pin and the PCL facet was 93.1 ± 3.9° as measured on intraoperative radiographs. The mean distance from the centre of the tibial tunnel outlet to the inferior border of the PCL insertion was 5.6 ± 1.1 mm, and the distance from the centre of the tibial tunnel outlet to the outer border of the PCL insertion as a percentage of the length of the inferior border of PCL insertion was 42.2 ± 6.3%. Conclusion: The tibial capsular reflection and septum in the posterior compartment are safe and reliable soft‐tissue landmark for tibial tunnel drilling in PCLR. Level of Evidence: Level Ⅳ. [ABSTRACT FROM AUTHOR]

There is currently no consensus on the optimal placement of the tibial tunnel for double-bundle posterior cruciate ligament (PCL) reconstruction. The purpose of this study was to compare the clinical and radiologic outcomes of double-bundle PCL reconstruction utilizing anatomic versus low tibial tunnels. We conducted a retrospective cohort study involving patients who underwent double-bundle PCL reconstruction between Jan 2019 and Jan 2022, with a minimum follow-up of 2 years (n = 36). Based on the tibial tunnel position on postoperative computed tomography, patients were categorized into two groups: anatomic placement (group A; n = 18) and low tunnel placement (group L; n = 18). We compared the range of motion, stability test, complications, and side-to-side differences in tibial posterior translation using kneeling stress radiography between the two groups. There were no significant differences between the groups regarding clinical outcomes or complication rates. No significant differences in the posterior drawer test and side-to-side difference on kneeling stress radiography (2.5 ± 1.2 mm in group A vs. 3.7 ± 2.0 mm in group L; p = 0.346). In conclusion, the main findings of this study indicate that both anatomic tunnel and low tibial tunnel placements in double-bundle PCL reconstruction demonstrated comparable and satisfactory clinical and radiologic outcomes, with similar overall complication rates at the 2-year follow-up. [ABSTRACT FROM AUTHOR]

Abstract Background Lowering the exit position of the tibial tunnel can improve the clinical efficacy of posterior cruciate ligament (PCL) reconstruction, however, there is no unified positioning standard. This study aimed to use novel soft tissue landmarks to create a low tunnel. Methods A total of 14 human cadaveric knees and 12 patients with PCL injury were included in this study. Firstly, we observed the anatomical position between the PCL, posterior septum, and other tissue, and evaluated the relationship between the center of the low tibial tunnel (SP tunnel) and posterior septum and distal reflection of posterior capsule, and using computed tomography (CT) to evaluate distance between the center of the SP tunnel with bony landmarks. Then, evaluated the blood vessels content in the posterior septum with HE staining. Finally, observed the posterior septum and distal reflection of the posterior capsule under arthroscopy to explore the clinical feasibility of creating a low tibial tunnel, and assessed the risk of surgery by using ultrasound to detect the distance between the popliteal artery and the posterior edge of tibial plateau bone cortex. Results In all 14 cadaveric specimens, the PCL tibial insertions were located completely within the posterior medial compartment of the knee. The distance between the center of the SP tunnel and the the articular surface of tibial plateau was 9.4 ± 0.4 mm. All SP tunnels retained an intact posterior wall, which was 1.6 ± 0.3 mm from the distal reflection of the posterior capsule. The distances between the center of the SP tunnel and the the articular surface of tibial plateau, the champagne glass drop-off were 9.2 ± 0.4 mm (ICC: 0.932, 95%CI 0.806–0.978) and 1.5 ± 0.2 mm (ICC:0.925, 95%CI 0.788–0.975) in CT image. Compared with the posterior capsule, the posterior septum contained more vascular structures. Last, all 12 patients successfully established low tibial tunnels under arthroscopy, and the distance between the posterior edge of tibial plateau bone cortex and the popliteal artery was 7.8 ± 0.3, 9.4 ± 0.4 and 7.4 ± 0.3 mm at 30°, 60° and 90° flexion angels after filling with water and supporting with shaver in posterior-medial compartment of knee joint. Conclusions A modified low tibial tunnel could be established in the PCL anatomical footprint by using the posterior septum and posterior capsule as landmarks.

Background: Lowering the exit position of the tibial tunnel can improve the clinical efficacy of posterior cruciate ligament (PCL) reconstruction, however, there is no unified positioning standard. This study aimed to use novel soft tissue landmarks to create a low tunnel. Methods: A total of 14 human cadaveric knees and 12 patients with PCL injury were included in this study. Firstly, we observed the anatomical position between the PCL, posterior septum, and other tissue, and evaluated the relationship between the center of the low tibial tunnel (SP tunnel) and posterior septum and distal reflection of posterior capsule, and using computed tomography (CT) to evaluate distance between the center of the SP tunnel with bony landmarks. Then, evaluated the blood vessels content in the posterior septum with HE staining. Finally, observed the posterior septum and distal reflection of the posterior capsule under arthroscopy to explore the clinical feasibility of creating a low tibial tunnel, and assessed the risk of surgery by using ultrasound to detect the distance between the popliteal artery and the posterior edge of tibial plateau bone cortex. Results: In all 14 cadaveric specimens, the PCL tibial insertions were located completely within the posterior medial compartment of the knee. The distance between the center of the SP tunnel and the the articular surface of tibial plateau was 9.4 ± 0.4 mm. All SP tunnels retained an intact posterior wall, which was 1.6 ± 0.3 mm from the distal reflection of the posterior capsule. The distances between the center of the SP tunnel and the the articular surface of tibial plateau, the champagne glass drop-off were 9.2 ± 0.4 mm (ICC: 0.932, 95%CI 0.806–0.978) and 1.5 ± 0.2 mm (ICC:0.925, 95%CI 0.788–0.975) in CT image. Compared with the posterior capsule, the posterior septum contained more vascular structures. Last, all 12 patients successfully established low tibial tunnels under arthroscopy, and the distance between the posterior edge of tibial plateau bone cortex and the popliteal artery was 7.8 ± 0.3, 9.4 ± 0.4 and 7.4 ± 0.3 mm at 30°, 60° and 90° flexion angels after filling with water and supporting with shaver in posterior-medial compartment of knee joint. Conclusions: A modified low tibial tunnel could be established in the PCL anatomical footprint by using the posterior septum and posterior capsule as landmarks. [ABSTRACT FROM AUTHOR]

Purpose: To investigate progressive tunnel widening and its correlation with postoperative outcomes after anterior cruciate ligament (ACL) reconstruction using allografts. Methods: Sixty-five patients who underwent ACL reconstruction using a tibialis anterior allograft between 2015 and 2017 were enrolled. Femoral and tibial tunnel widths were measured on anteroposterior (AP) and lateral radiographs immediately and at 3, 6, 12, and 24 months postoperatively. Average femoral and tibial tunnel widths in AP and lateral views were calculated at three different measurement points. Tunnel widening was calculated as the difference in tunnel width immediately and 2 years postoperatively. The correlation between tunnel widening and the postoperative results was analysed. Results: Tunnel width changes between immediate and 2 years postoperatively were as follows, in AP and lateral views, respectively: femur, 3.0 mm ± 1.5 mm and 2.4 mm ± 1.4 mm; and tibia, 2.8 mm ± 1.4 mm and 2.9 mm ± 1.5 mm. Femoral tunnel widths significantly increased until 1 year, but not from 1 to 2 years postoperatively. Tibial tunnel width significantly increased until 2 years postoperatively. In all tunnels, the increments in tunnel widening decreased over time. Increased knee laxity significantly correlated with greater femoral tunnel widening in AP (r = 0.346, P = 0.006) and lateral views (r = 0.261, P = 0.049). Conclusion: Femoral tunnel widths gradually increased until 1 year postoperatively, and tibial tunnel widths increased until 2 years after ACL reconstruction with allografts. The tunnel widening rate gradually decreased over time. Femoral tunnel widening of 3.7 mm and 3.2 mm on AP and lateral views, respectively, were the cut-off values for postoperative knee laxity. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Background/objective: Accurate tibial tunnel creation is crucial for successful transtibial pullout repair of medial meniscus (MM) posterior root tears (MMPRTs). This study aimed to evaluate the accuracy of the newly developed Zimmer Biomet Root Aiming (ZeBRA) guide for transtibial pullout repair of MMPRTs. Methods: This study included 50 patients who underwent transtibial pullout repair using the Unicorn Meniscal Root (UMR) (n = 25) and ZeBRA (n = 25) guides. The expected anatomic centre (AC) and tibial tunnel centre (TC) were assessed using three-dimensional postoperative computed tomography (CT) images. The expected AC was defined as the centre of the circle tangent to the triangular footprint of the MM posterior root. The expected AC and TC on the tibial surface were assessed using the percentage-based posterolateral location on the tibial surface. The absolute distance between the AC and TC (mm) was evaluated. Results: The mean AC location was 76.1% ± 3.1% posterior and 40.8% ± 2.1% lateral, whereas the mean TC location was 76.7% ± 5.3% posterior and 37.2% ± 3.6% lateral using the UMR guide and 75.8% ± 3.1% posterior and 36.5% ± 2.4% lateral using the ZeBRA guide. No significant difference was observed in the absolute distance between the UMR and ZeBRA guides (3.9 ± 1.4 and 3.8 ± 1.3 mm, respectively; p = 0.617). Conclusions: The newly developed ZeBRA guide allows accurate tibial tunnel creation, and its accuracy is comparable to that of the conventional UMR guide. Tibial tunnels were created at optimal positions using both guides, and the choice of the guide would depend on the surgeon's preference.

Objective In order to reduce the “killer turn” effect, various tibial tunnels have been developed. However, few studies investigated the biomechanical effects of different tibial tunnels during PCL reconstruction. This study aims to compare the time‐zero biomechanical properties of anteromedial, anterolateral, lower anteromedial, and lower anterolateral tibial tunnels in transtibial posterior cruciate ligament (PCL) reconstruction under load‐to‐failure loading. Methods Porcine tibias and bovine extensor tendons were used to simulate in vitro transtibial PCL reconstruction. Forty bovine extensor tendons and 40 porcine tibias were randomly divided into four experimental groups: anteromedial tunnel group (AM group, n = 10), anterolateral tunnel group (AL group, n = 10), lower anteromedial tunnel group (L‐AM group, n = 10), and lower anterolateral tunnel group (L‐AL group, n = 10). The biomechanical test was then carried out in each group using the load‐to‐failure test. The ultimate load (in newtons), yield load (in newtons), tensile stiffness (in newtons per millimeter), load‐elongation curve, failure mode, and tibial tunnel length (in millimeter) were recorded for each specimen. One‐way analysis of variance (ANOVA) was used to compare the mean differences among the four groups. Results The biomechanical outcomes showed that there were no differences in the mean tensile stiffness and failure mode among four groups. The ultimate load and yield load of the L‐AM group were significantly higher than those of other three groups (P 0.05). There was significant statistical difference in the length of tibial tunnel between anatomic groups (AM and AL) and lower groups (L‐AM and L‐AL) (P

There is currently no consensus on the optimal placement of the tibial tunnel for double-bundle posterior cruciate ligament (PCL) reconstruction. The purpose of this study was to compare the clinical and radiologic outcomes of double-bundle PCL reconstruction utilizing anatomic versus low tibial tunnels. We conducted a retrospective cohort study involving patients who underwent double-bundle PCL reconstruction between Jan 2019 and Jan 2022, with a minimum follow-up of 2 years (n = 36). Based on the tibial tunnel position on postoperative computed tomography, patients were categorized into two groups: anatomic placement (group A; n = 18) and low tunnel placement (group L; n = 18). We compared the range of motion, stability test, complications, and side-to-side differences in tibial posterior translation using kneeling stress radiography between the two groups. There were no significant differences between the groups regarding clinical outcomes or complication rates. No significant differences in the posterior drawer test and side-to-side difference on kneeling stress radiography (2.5 ± 1.2 mm in group A vs. 3.7 ± 2.0 mm in group L; p = 0.346). In conclusion, the main findings of this study indicate that both anatomic tunnel and low tibial tunnel placements in double-bundle PCL reconstruction demonstrated comparable and satisfactory clinical and radiologic outcomes, with similar overall complication rates at the 2-year follow-up.

Abstract Background All-inside anterior cruciate ligament reconstruction (ACLR) is a novel technique that has gained attention due to its minimally invasive. However, evidence surrounding the efficacy and safety between all-inside and complete tibial tunnel ACLR are lacking. Present work was aimed to compare clinical outcome for ACLR performed with an all-inside versus a complete tibial tunnel technique. Methods Systematic searches were conducted of published literature on PubMed, Embase, and Cochrane for studies according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines up to May 10, 2022. The outcomes included KT-1000 arthrometer ligament laxity test, International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner activity scale, and Knee Society Score (KSS) Scale, and tibial tunnel widening. Complications of interest extracted were graft re-ruptures and evaluated the graft re-rupture rate. Data from published RCTs meeting inclusion criteria were extracted and analyzed, and all the extracted data are pooled and analyzed by RevMan 5.3. Results A total of 8 randomized controlled trials involving 544 patients (consisting of 272 all-inside and 272 complete tibial tunnel patients) were included in the meta-analysis. We found clinical outcomes (International Knee Documentation Committee [IKDC] subjective score: mean difference [MD], 2.22; 95% CI, 0.23–4.22; p = 0.03; Lysholm score: MD, 1.09; 95% CI, 0.25–1.93; p = 0.01; Tegner activity scale: MD, 0.41; 95% CI, 0.11–0.71; p

Objective: In order to reduce the "killer turn" effect, various tibial tunnels have been developed. However, few studies investigated the biomechanical effects of different tibial tunnels during PCL reconstruction. This study aims to compare the time‐zero biomechanical properties of anteromedial, anterolateral, lower anteromedial, and lower anterolateral tibial tunnels in transtibial posterior cruciate ligament (PCL) reconstruction under load‐to‐failure loading. Methods: Porcine tibias and bovine extensor tendons were used to simulate in vitro transtibial PCL reconstruction. Forty bovine extensor tendons and 40 porcine tibias were randomly divided into four experimental groups: anteromedial tunnel group (AM group, n = 10), anterolateral tunnel group (AL group, n = 10), lower anteromedial tunnel group (L‐AM group, n = 10), and lower anterolateral tunnel group (L‐AL group, n = 10). The biomechanical test was then carried out in each group using the load‐to‐failure test. The ultimate load (in newtons), yield load (in newtons), tensile stiffness (in newtons per millimeter), load‐elongation curve, failure mode, and tibial tunnel length (in millimeter) were recorded for each specimen. One‐way analysis of variance (ANOVA) was used to compare the mean differences among the four groups. Results: The biomechanical outcomes showed that there were no differences in the mean tensile stiffness and failure mode among four groups. The ultimate load and yield load of the L‐AM group were significantly higher than those of other three groups (P < 0.05). For the AM group, its ultimate load is significantly higher than that of the L‐AL group (P < 0.05), and its yield load is higher than that of the AL group and L‐AL group (P < 0.05). However, we found no significant differences in either ultimate load or yield load between AL group and L‐AL group (P > 0.05). There was significant statistical difference in the length of tibial tunnel between anatomic groups (AM and AL) and lower groups (L‐AM and L‐AL) (P < 0.05). Conclusion: Compared with the anteromedial, anterolateral, and lower anterolateral tibial tunnel, the lower anteromedial tibial tunnel showed better time‐zero biomechanical properties including ultimate load and yield load in transtibial PCL reconstruction. [ABSTRACT FROM AUTHOR]

Background: All-inside anterior cruciate ligament reconstruction (ACLR) is a novel technique that has gained attention due to its minimally invasive. However, evidence surrounding the efficacy and safety between all-inside and complete tibial tunnel ACLR are lacking. Present work was aimed to compare clinical outcome for ACLR performed with an all-inside versus a complete tibial tunnel technique. Methods: Systematic searches were conducted of published literature on PubMed, Embase, and Cochrane for studies according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines up to May 10, 2022. The outcomes included KT-1000 arthrometer ligament laxity test, International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner activity scale, and Knee Society Score (KSS) Scale, and tibial tunnel widening. Complications of interest extracted were graft re-ruptures and evaluated the graft re-rupture rate. Data from published RCTs meeting inclusion criteria were extracted and analyzed, and all the extracted data are pooled and analyzed by RevMan 5.3. Results: A total of 8 randomized controlled trials involving 544 patients (consisting of 272 all-inside and 272 complete tibial tunnel patients) were included in the meta-analysis. We found clinical outcomes (International Knee Documentation Committee [IKDC] subjective score: mean difference [MD], 2.22; 95% CI, 0.23–4.22; p = 0.03; Lysholm score: MD, 1.09; 95% CI, 0.25–1.93; p = 0.01; Tegner activity scale: MD, 0.41; 95% CI, 0.11–0.71; p < 0.01; Tibial Tunnel Widening: MD = − 1.92; 95% CI, − 3.58 to − 0.25; p = 0.02; knee laxity: MD = 0.66; 95% CI, 0.12–1.20; p = 0.02; and graft re-rupture rate: RR, 1.97;95% CI, 0.50–7.74; P = 0.33) in the all-inside and complete tibial tunnel group. The findings also indicated that all-inside may be more advantageous in tibial tunnel healing. Conclusion: Our meta-analysis indicated that the all-inside ACLR was superior to complete tibial tunnel ACLR in functional outcomes and tibial tunnel widening. However, the all-inside ACLR was not entirely superior to complete tibial tunnel ACLR in knee laxity measured, and graft re-rupture rate. [ABSTRACT FROM AUTHOR]

No consensus has been reached on the optimal position of PCL tibial tunnel. The purpose of this study was to compare the biomechanical properties of proximal, distal and anatomic tibial tunnel in transtibial posterior cruciate ligament reconstruction. An in-vitro model of transtibial posterior cruciate ligament reconstruction was simulated using porcine tibias and bovine extensor tendons. Two models of biomechanical testing, load-to-failure loading, and cyclic loading, were performed in this study. The load-to-failure loading found that distal tibial tunnel resulted in greater ultimate load and yield load than the anatomic and proximal tunnel group (p < 0.05), whereas there were no significant differences in mean tensile stiffness among three groups (p > 0.05). The cyclic loading found no differences in the graft displacement at 250, 500, and 1000 cycles among three groups (p > 0.05). It was found that distal tibial tunnel showed superior ultimate load and yield load in load-to-failure loading testing compared with proximal and anatomic tibial tunnels, whereas no significant difference was found in terms of the mean displacement of the survived grafts in cyclic loading testing among three groups. Graphical abstract [ABSTRACT FROM AUTHOR]

Introduction: Tibial fixation site of graft in arthroscopic Anterior Cruciate Ligament (ACL) reconstruction has an effect on anterior displacement and internal rotation of the tibia. The position of the interference screw determines the final orientation of the graft. The screw position in turn depends on the position of the tibial guidewire. The tibial guidewire can be placed before introducing the graft or after the graft placement. There are no studies in the literature comparing the outcome of tibial guidewire placement timing in arthroscopic ACL reconstruction. Aim: To compare the functional outcome of arthroscopic ACL reconstruction, with placing the tibial guidewire before and after graft passage. Materials and Methods: This prospective longitudinal study was conducted at Government Medical College, Thiruvananthapuram, India, from February 2020 to January 2021, among patients undergoing arthroscopic ACL reconstruction. A total of 84 patients with an isolated ACL tear, who underwent arthroscopic ACL reconstructionwere followedup for a minimum period of nine months. Two groups were studied, each with 42 patients. In group 1, the tibial guidewire was placed posterolaterally in the tibial tunnel and then the graft was pulled through femoral and tibial tunnels. In group 2, the guidewire was placed after the graft was passed through femoral and tibial tunnels. Functional outcomes were evaluated with International Knee Documentation Committee (IKDC) and Lysholm knee scores after nine months. Statistical analyses were carried out using Statistical Package for Social Sciences (SPSS) statistics version 22.0. Results: The median age of the study subjects were 27 (22;35) years. Fifty nine (70.2%) patients were males. Forty eight (57.1%) patients had left-sided injuries. The majority of injuries (n= 58, 69%) were due to sports injuries. In 14 patients (16.7%), the mode of injury was due to road traffic accidents and in 12 patients (14.3%) it was due to a fall. In the majority of the cases (n=50, 59.5%), the duration between injury and ACL reconstruction was 3 months. The mean IKDC subjective score of group 1 was 86±5.51 and that of group 2 was 81.9±6.64; (p-value=0.003). The mean Lysholm score of group 1 was 84.9±8.73 and that of group 2 was 79.6±9.56; (p-value=0.009). Conclusion: Arthroscopic ACL reconstruction placing the tibial guidewire posterolaterally prior to graft passage has got a better functional outcome compared to placing the guidewire after passing the graft. Prior placement of guidewire before graft ensures the posterolateral position of the interference screw at the tibial tunnel and increases the graft obliquity. [ABSTRACT FROM AUTHOR]

Abstract Background Transportal (TP) and all-inside techniques (AIT) are the most commonly used anterior cruciate ligament (ACL) reconstruction procedures in current clinical practice. However, there is an ongoing debate over which procedure is superior. Therefore, the purpose of this systematic review was to evaluate and compare the clinical outcomes and complications of these two techniques to propose recommendations for future application. Our primary hypothesis was that AIT is a superior ACLR technique compared to TP. Methods A systematic literature review, using PRISMA guidelines, was conducted using PubMed, Medline, Google Scholar, and EMBASE, up to February 2021 to identify studies focusing on AIT and TP techniques of ACL reconstruction. We excluded animal experiments, cadaveric studies, retrospective studies, case reports, technical notes, and studies without quantitative data. Patients’ characteristics, surgical technical features, along with postoperative follow-up and complications were extracted and reported accordingly. Methodological quality of the included studies was assessed using the Modified Coleman Methodology Score (MCMS). Results A total of 44 studies were selected for this review, of which four were comparative studies. A total of 923 patients underwent AIT and 1678 patients underwent the TP technique for ACLR. A single semitendinosus graft was commonly used in the AIT compard to combined semitendinosus and gracilis graft in the TP group. The postoperative increase in International Knee Documentation Committee (IKDC), Lysholm, KT-1000, and Short Form-12 (physical and mental) scores were similar in the AIT group and the TP group. Contrastingly, the VAS pain score was significantly lower in the AIT group compared to the TP group. Furthermore, the pooled complication rates from all studies were similar between the two groups (AIT: 54 patients, 8.26% vs. PT: 55 patients, 6.62%). However, the four studies that prospectively compared AIT and TP techniques showed lesser complications in the AIT group than the TP group. Conclusion Since the future trend in orthopedic surgery is toward less invasive and patients’ satisfaction with good outcomes, AIT is a good alternative method considering preserving bony tissue and gracilis tendon with less post-operative pain, along with more knee flexor strength and equal outcomes compared to conventional ACL reconstruction surgery. Level of Evidence II.

Introduction: Tibial fixation site of graft in arthroscopic Anterior Cruciate Ligament (ACL) reconstruction has an effect on anterior displacement and internal rotation of the tibia. The position of the interference screw determines the final orientation of the graft. The screw position in turn depends on the position of the tibial guidewire. The tibial guidewire can be placed, before introducing the graft or after the graft placement. There are no studies in the literature comparing the outcome of tibial guidewire placement timing in arthroscopic ACL reconstruction. Aim: To compare the functional outcome of arthroscopic ACL reconstruction, with placing the tibial guidewire before and after graft passage. Materials and Methods: This prospective longitudinal study was conducted at Government Medical College, Thiruvananthapuram, India, from February 2020 to January 2021, among patients undergoing arthroscopic ACL reconstruction. A total of 84 patients with an isolated ACL tear, who underwent arthroscopic ACL reconstruction were followed-up for a minimum period of nine months. Two groups were studied, each with 42 patients. In group 1, the tibial guidewire was placed posterolaterally in the tibial tunnel and then, the graft was pulled through femoral and tibial tunnels. In group 2, the guidewire was placed after the graft was passed through femoral and tibial tunnels. Functional outcomes were evaluated with International Knee Documentation Committee (IKDC) and Lysholm knee scores after nine months. Statistical analyses were carried out using Statistical Package for Social Sciences (SPSS) statistics version 22.0. Results: The median age of the study subjects were 27 (22;35) years. Fifty nine (70.2%) patients were males. Forty eight (57.1%) patients had left-sided injuries. The majority of injuries (n=58, 69%) were due to sports injuries. In 14 patients (16.7%), the mode of injury was due to road traffic accidents and in 12 patients (14.3%) it was due to a fall. In the majority of the cases (n=50, 59.5%), the duration between injury and ACL reconstruction was three months. The mean IKDC subjective score of group 1 was 86±5.51 and that of group 2 was 81.9±6.64; (p-value=0.003). The mean Lysholm score of group 1 was 84.9±8.73 and that of group 2 was 79.6±9.56; (p-value=0.009). Conclusion: Arthroscopic ACL reconstruction placing the tibial guidewire posterolaterally prior to graft passage has got a better functional outcome compared to placing the guidewire, after passing the graft. Prior placement of guidewire, before graft ensures the posterolateral position of the interference screw at the tibial tunnel and increases the graft obliquity.

Purpose: Correct placement of the femoral and tibial tunnels in the anatomic footprint during anterior cruciate ligament reconstruction (ACLR) is paramount for restoring rotatory knee stability. Recent studies have looked at surgeon volume and its outcomes on procedures such as total knee arthroplasty and infection rates, but only few studies have specifically examined tunnel placement after ACLR based on surgeon volume. The purpose of this study was to compare the placement of femoral and tibial tunnels during ACLR between high-volume and low-volume surgeons. It was hypothesized that high-volume surgeons would have more anatomic tunnel placement compared with low-volume surgeons. Methods: A retrospective review of all ACLR performed between 2015 and 2019 at an integrated health care system consisting of both academic and community hospitals with 68 orthopaedic surgeons was conducted. Surgeon volume was categorized as less than 35 ACLR per year (low volume) and 35 or more ACLR per year (high volume). Femoral tunnel placement for each patient was determined using an exact strict lateral radiograph (less than 6 mm of offset between the posterior halves of the medial and lateral condyles) taken after the primary ACLR using the quadrant method. The centre of the femoral tunnel was measured in relation to the posterior–anterior (PA) and proximal–distal (PD) dimensions (normal centre of anatomic footprint: PA 25% and PD 29%). Tibial tunnel placement for each patient was determined on the same lateral radiographs by measuring the mid-sagittal tibial diameter and the centre of the tibial attachment area of the ACL from the anterior tibial margin (normal centre of anatomic footprint: 43%). Each lateral radiograph was reviewed by one of two blinded reviewers. Results: A total of 4500 patients were reviewed, of which 645 patients met all the inclusion/exclusion criteria and were included in the final analysis. There were 228 patients in the low-volume group and 417 patients in the high-volume group. Low-volume surgeons performed a mean of 5 ACLRs per year, whereas surgeons in the high-volume group performed a mean of 40 ACLRs per year. In the PA dimension, the low-volume group had significantly more anterior femoral tunnel placement compared with the high-volume group (32 ± 10% vs 28 ± 9%, p < 0.01). In the PD dimension, the low-volume group had statistically significant more proximal femoral tunnel placement compared to the high-volume group (32 ± 9% vs 35 ± 9%, p < 0.01). For the tibial tunnel, the low-volume group had significantly more posterior tibial tunnel placement compared with the high-volume group (41 ± 10% vs 38 ± 7%, p < 0.01). Conclusion: Low-volume surgeons placed their femoral tunnels significantly more anterior and proximal (high) during ACLR, and placed their tibial tunnels significantly more posterior, compared with high-volume surgeons. Prior research has indicated that anatomic placement of the femoral and tibial tunnels during ACLR leads to improved rotatory knee stability. The findings of this study demonstrate the importance of surgical volume and experience during ACLR. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: The all-inside tibial tunnel preparation technique of arthroscopic anterior cruciate ligament (ACL) reconstruction differs from traditional complete tibial tunnel technique in using closed tibial sockets, dual-cortical suspensory graft-fixation, quadrupled semitendinosus tendon graft and lesser bone removal. The study aims to find out if all-inside technique differs from complete tibial tunnel technique of single bundle ACL reconstruction in terms of graft dimensions, functional and clinical outcomes. Methods: A prospective comparative study was conducted including 80 patients with isolated ACL tears, divided into 2 groups of 40 patients each without any randomization. The two techniques differed in tibial tunnel preparation. Group 1 underwent ACL reconstruction with a complete tibial tunnel drilled from the anteromedial tibial cortex and group 2 underwent all-inside tibial socket preparation. Duration of the surgery, perioperative and midterm complications were noted. All patients had 24 month follow-up. Functional outcome scores (Tegner-Lysholm knee scoring scale and IKDC score) were assessed preoperatively and postoperatively at 6 months and 24 months. Hamstring and quadriceps muscle strength was assessed preoperatively and postoperatively at 6 months, 9 months and 24 months. Visual analogue score (VAS) for knee pain was assessed preoperatively and postoperatively at day 2, 2 weeks, 6 weeks, 6 months and 24 months. Results: Quadrupled semitendinosus tendon graft was significantly thicker than doubled semitendinosus and gracilis tendons graft (8.17 ± 0.58 vs 8.71 ± 0.4, p < 0.0001). The VAS score for knee pain at 2 and 6 weeks were lower in group 2 (5.75 ± 0.6 and 1.78 ± 1.0) as compared to group 1 (6.50 ± 0.5 and 2.5 ± 0.8) and the difference was statistically significant (P = 0.0007 and p = 0.002 respectively). There were no statistically significant differences in functional outcome scores and quadriceps muscle strength between the two groups. However, there were significant difference in hamstring power in two groups. Conclusion: The all-inside technique has the advantages of using a single tendon graft, lesser early postoperative pain with similar clinical and functional outcomes compared to the complete tibial tunnel technique. Level of Evidence IIProspective comparative study [ABSTRACT FROM AUTHOR]

Background: Transportal (TP) and all-inside techniques (AIT) are the most commonly used anterior cruciate ligament (ACL) reconstruction procedures in current clinical practice. However, there is an ongoing debate over which procedure is superior. Therefore, the purpose of this systematic review was to evaluate and compare the clinical outcomes and complications of these two techniques to propose recommendations for future application. Our primary hypothesis was that AIT is a superior ACLR technique compared to TP. Methods: A systematic literature review, using PRISMA guidelines, was conducted using PubMed, Medline, Google Scholar, and EMBASE, up to February 2021 to identify studies focusing on AIT and TP techniques of ACL reconstruction. We excluded animal experiments, cadaveric studies, retrospective studies, case reports, technical notes, and studies without quantitative data. Patients' characteristics, surgical technical features, along with postoperative follow-up and complications were extracted and reported accordingly. Methodological quality of the included studies was assessed using the Modified Coleman Methodology Score (MCMS). Results: A total of 44 studies were selected for this review, of which four were comparative studies. A total of 923 patients underwent AIT and 1678 patients underwent the TP technique for ACLR. A single semitendinosus graft was commonly used in the AIT compard to combined semitendinosus and gracilis graft in the TP group. The postoperative increase in International Knee Documentation Committee (IKDC), Lysholm, KT-1000, and Short Form-12 (physical and mental) scores were similar in the AIT group and the TP group. Contrastingly, the VAS pain score was significantly lower in the AIT group compared to the TP group. Furthermore, the pooled complication rates from all studies were similar between the two groups (AIT: 54 patients, 8.26% vs. PT: 55 patients, 6.62%). However, the four studies that prospectively compared AIT and TP techniques showed lesser complications in the AIT group than the TP group. Conclusion: Since the future trend in orthopedic surgery is toward less invasive and patients' satisfaction with good outcomes, AIT is a good alternative method considering preserving bony tissue and gracilis tendon with less post-operative pain, along with more knee flexor strength and equal outcomes compared to conventional ACL reconstruction surgery. Level of Evidence II. [ABSTRACT FROM AUTHOR]

Background/objective: The purpose of the study was to evaluate the change in orientation of the reconstructed ACL with the change in position of the interference screw in the tibial tunnel. Method: It was a retrospective review of Magnetic Resonance Imaging (MRI) in which 51 normal and 61 MRI of patients who had undergone ACL reconstruction at our institute were evaluated. Postoperative ACL reconstruction group MRI studies were obtained and evaluated by two sports medicine fellows independently to assess the position of interference screw, distance of the graft from the anterior cortex of tibia and inclination of the graft. The data was collected and compared with MRI data of normal ACL patients. Results: There were total 61 patients with ACL reconstruction. 32 patients had anterior screw placement and 29 patients had posterior screw placement in the tibial tunnel. The distance of the graft from the anterior cortex was 39.18% in ACL intact group, 50.35% in anterior screw group and 41.64% in posterior screw group. The inclination angle was 44.49⁰ in intact group, 49.69° and 42.20° in anterior and posterior screw group respectively. The difference between intact group and anterior screw group was statistically significant. Conclusion: Posterior position of interference screw in tibial tunnel increases graft obliquity than anterior position and decreases its distance from the anterior tibial cortex. This increased graft obliquity and distance from the anterior tibial cortex is similar to the native ACL.

The reconstruction of a ruptured anterior cruciate ligament (ACL) is a well established procedure for repair of ACL injury. Knowledge of normal appearances, the expected postoperative changes over time, and potential acute and chronic complications of this reconstruction procedure are essential. This study illustrates the role of MRI in evaluation of ACL reconstructions and their complications. MR imaging is the modality of choice for evaluation of ACL graft reconstruction. ACL graft complications such as abnormal tunnel positioning, partial and complete graft tears, arthrofibrosis, and tunnel cysts can be reliably assessed using MRI.

Introduction: Anterior cruciate ligament (ACL) reconstruction is a common orthopedic procedure, employing various grafts such as the hamstring tendon, bone-patellar bone, and quadriceps tendon. Fixation methods include suspensory loop with button, interferential screw, and cortical fixation. The optimal screw diameter for tibial tunnel fixation remains undefined, with choices ranging from 1mm smaller to 1-2 mm larger than the tunnel diameter. Screw-related complications such as breakage and thread flattening are concerns. This study was to determine the ideal screw diameter for secure graft fixation in the tibial tunnel during ACL reconstruction., Materials and Methods: A novel arthroscopic probe technique was utilized to assess tibial tunnel bone integrity. Bone quality was categorized into weak, strong, and very strong. Screw size selection, either equal to or 1-2 mm larger than the tunnel diameter, was based on bone quality. Screw lengths varied from 25 mm to 35 mm., Results: The novel technique significantly reduced screw-related complications, from 9.6% (24 out of 248 patients) to 0.5% (l out of 187 patients). The need for additional cortical stabilization decreased from 14.5% (36 out of248 patients) to 1.6% (3 out of 187 patients)., Conclusion: The low-cost, efficient 2-min probe test is a secure and effective method for selecting interferential screws in ACL reconstruction, minimizing complications, and additional stabilization needs., Competing Interests: Conflict of Interest: Nil, (Copyright: © Indian Orthopaedic Research Group.)

Purpose: A medial meniscus posterior root tear results in the loss of meniscal circumferential hoop stress and causes a pathological posteromedial extrusion of the medial meniscus. Although creating a tibial tunnel in the anatomic place improves postoperative medial meniscus posterior extrusion, no studies have evaluated the relationship between tibial tunnel position and clinical outcomes. This study aimed to evaluate how tibial tunnel positioning of medial meniscus posterior root pullout repair affects meniscal healing status and clinical outcomes. Methods: Sixty-two patients with 64 medial meniscus posterior root tears (mean age 62.8 ± 7.9 years) who had undergone pullout repairs and second-look arthroscopies were included. All 62 patients were Lachman test negative. Three-dimensional computed tomography images of the tibial surface were evaluated using a rectangular measurement grid to assess the tibial tunnel centre and medial meniscus posterior root attachment centre. Spearman's rank correlation analysis was undertaken to determine displacement distance from the medial meniscus posterior root attachment centre to the tibial tunnel centre and a meniscal healing score, as well as clinical outcomes at 1 year post-repair. Results: Tibial tunnel centres were located more anteriorly and medially than the medial meniscus posterior root attachment centre (mean distance 5.0 ± 2.2 mm). The mean meniscal healing score was 6.7 ± 1.8 of 10 possible points. The 1-year postoperative clinical scores showed significant improvement compared with preoperative scores for all the items. There was a significant negative correlation in the absolute distance between the medial meniscus posterior root attachment centre and the tibial tunnel centre with the meniscal healing score (ρ = − 0.39, p = 0.002). Furthermore, there were significant positive correlations between the distance between the medial meniscus posterior root attachment centre and the tibial tunnel centre in the mediolateral direction and patient-based clinical outcomes (ρ = 0.25–0.43, p < 0.05). Conclusion: Accurate placement of a tibial tunnel, especially in the mediolateral direction, significantly improved meniscal healing and clinical outcomes at 1 year following medial meniscus posterior root repair. Surgeons should create a medial meniscus posterior root tibial tunnel at the anatomic attachment with particular attention to the mediolateral position. Level of evidence: Level IV. [ABSTRACT FROM AUTHOR]

PURPOSE OF THE STUDY The purpose of this study was to evaluate the position of tibial tunnel (TT) and femoral tunnels (FT) performed by using the anteromedial (AM) portal technique and its effect on the aperture of FT. MATERIAL AND METHODS A total 44 patients operated for anterior cruciate ligament (ACL) rupture by AM portal technique between January 2013 and July 2015, were included in this study. They were subjected to a magnetic resonance imaging of the knee to assess the FT, dimensions of the FT aperture and TT. The location of the ACL graft within the joint was compared with the intact ACL of healthy individuals. The patients were also evaluated using Lysholm and IKDC subjective scores for functional outcome. RESULTS The mean FT angle on both the coronal plane (42.88°±5.83°) and the sagittal plane (68.47°±9.57°) was significantly different from the intra-articular part of the hamstring autograft angles (74.93°±7.27° and 58.74°±4.88°, respectively) (p<0.0001). The mean distance of the FT aperture was 13.18 (±2.49) mm on vertical axis, 10.97 (±1.50) mm on the sagittal axis (p<0.0001). The difference between TT axis and the axis of the intra-articular part of autograft on both coronal (72.78°±4.67° and 74.93°±7.27°, respectively) and sagittal planes (60.12°±5.53° and 58.74°±4.88°, respectively) were not significant (p>0.05). DISCUSSION Ilingrowth et al. claimed that the FT were scattered in the very large distance and some of them were placed outside of anatomical range in the series included the cases performed with transtibial and transtibial independent techniques. In this series, in which we used a femoral guide to drill the FT at lateral femoral condyle at 2 or 10 o’clock position depended upon the site of operation, we obtained a consistent FT which is comparable with the intra-articular part of native ACL. Amano et al. found that the FT aperture enlargement was significant in the series when hamstring tendons were used as autograft, over a 6-month period. We also found a significant difference between the narrowest part of the FT (7.01 ± 1.05 mm) and its aperture (10.97 ± 1.50 mm in sagittal, 13.18 ± 2.49 mm in vertical direction). The enlargement was mainly in the vertical direction, due to the fact that the loads resulting from daily life are mostly on the horizontal plane. CONCLUSIONS The direction of intra-articular part of the ACL graft in the cases operated with the AM portal technique is significantly different from the FT direction in both the coronal and sagittal planes. The enlargement of the FT aperture is larger in the vertical axis compared to the sagittal axis. Although the long-term clinical consequences of asymmetrical enlargement of the FT aperture are not known yet, to avoid this potential risk, a technique to approximate the direction of FT to the intra-articular part of the ACL without changing the FT entry site, can be used. [ABSTRACT FROM AUTHOR]

Background: The drilling technique used to make a femoral tunnel is critically important for determining outcomes after anterior cruciate ligament (ACL) reconstruction. The 2 most common methods are the transtibial (TT) and anteromedial (AM) techniques. Purpose: To determine whether graft orientation and placement affect clinical outcomes by comparing clinical and radiological outcomes after single-bundle ACL reconstruction with the AM versus TT technique. Study Design: Systematic review; Level of evidence, 3. Methods: Articles in PubMed, EMBASE, the Cochrane Library, ISI Web of Science, Scopus, and MEDLINE were searched from inception until April 25, 2020, using the following Boolean operators: transtibial OR trans-tibial AND (anteromedial OR trans-portal OR independent OR three portal OR accessory portal) AND anterior cruciate ligament. Results: Of 1270 studies retrieved, 39 studies involving 11,207 patients were included. Of these studies, 14 were clinical, 13 were radiological, and 12 were mixed. Results suggested that compared with the TT technique, the AM technique led to significantly improved anteroposterior and rotational knee stability, International Knee Documentation Committee (IKDC) scores, and recovery time from surgery. A higher proportion of negative Lachman (P =.0005) and pivot-shift test (P =.0001) results, lower KT-1000 arthrometer maximum manual displacement (P =.00001), higher Lysholm score (P =.001), a higher incidence of IKDC grade A/B (P =.05), and better visual analog scale score for satisfaction (P =.00001) were observed with the AM technique compared with the TT technique. The AM drilling technique demonstrated a significantly shorter tunnel length (P =.00001). Significant differences were seen between the femoral and tibial graft angles in both techniques. Low overall complication and revision rates were observed for ACL reconstruction with the AM drilling technique, similar to the TT drilling technique. Conclusion: In single-bundle ACL reconstruction, the AM drilling technique was superior to the TT drilling technique based on physical examination, scoring systems, and radiographic results. The AM portal technique provided a more reproducible anatomic graft placement compared with the TT technique. [ABSTRACT FROM AUTHOR]

Background: It remains unclear if use of the lateral meniscus anterior horn (LMAH) as a landmark will produce consistent tunnel positions in the anteroposterior (AP) distance across the tibial plateau. Purpose: To evaluate the AP location of anterior cruciate ligament (ACL) reconstruction tibial tunnels utilizing the LMAH as an intra-articular landmark and to examine how tunnel placement affects knee stability and clinical outcomes. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective review was conducted of 98 patients who underwent primary ACL reconstruction with quadrupled hamstring tendon autografts between March 2013 and June 2017. Patients with unilateral ACL injuries and a minimum follow-up of 2 years were included in the study. All guide pins for the tibial tunnel were placed using the posterior border of the LMAH as an intra-articular landmark. Guide pins were evaluated with the Bernard-Hertel grid in the femur and the Stäubli-Rauschning method in the tibia. Patients were divided by the radiographic location of the articular entry point of the guide pin with relation to the anterior 40% of the tibial plateau. Outcomes were evaluated by the Marx Activity Scale and International Knee Documentation Committee (IKDC) form. Anterior knee laxity was evaluated using a KT-1000 arthrometer and graded with the objective portion of the IKDC form. Rotational stability was evaluated using the pivot-shift test. Results: A total of 60 patients were available for follow-up at a mean 28.6 months. The overall percentage of AP placement of the tibial tunnel was 39.3% ± 3.8% (mean ± SD; range, 31%-47%). Side-to-side difference of anterior knee laxity was significantly lower in the anterior group than the posterior group (1.2 ± 1.1 mm vs 2.5 ± 1.3 mm; P <.001; r = 0.51). The percentage of AP placement of the tibial tunnel demonstrated a positive medium correlation with side-to-side difference of anterior knee laxity as measured by a KT-1000 arthrometer (r = 0.430; P <.001). The anterior group reported significantly better distribution of IKDC grading as compared with the posterior group (26 grade A and 6 grade B vs 15 grade A and 13 grade B; P =.043; V = 0.297). The pivot-shift test results and outcome scores showed no significant differences between the groups. Conclusion: Using the posterior border of the LMAH as an intraoperative landmark yields a wide range of tibial tunnel locations along the tibial plateau, with anterior placement of the tibial tunnel leading toward improved anterior knee stability. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the influence of tibial tunnel position in pullout repair for a medial meniscus (MM) posterior root tear (MMPRT) on postoperative MM extrusion. Methods: Thirty patients (median age 63 years, range 35–72 years) who underwent transtibial pullout repairs for MMPRTs were included. Three-dimensional computed tomography images of the tibial surface were evaluated using a rectangular measurement grid for assessment of tibial tunnel position and MM posterior root attachment. Preoperative and postoperative MM medial extrusion (MMME) and posterior extrusion (MMPE) at 10° and 90° knee flexion were measured using open magnetic resonance imaging. Results: Tibial tunnel centers were located more anteriorly and more medially than the anatomic center (median distance 5.8 mm, range 0–9.3 mm). The postoperative MMPE at 90° knee flexion was significantly reduced after pullout repair, although there was no significant reduction in MMME or MMPE at 10° knee flexion after surgery. In the correlation analysis of the displacement between the anatomic center to the tibial tunnel center and improvements in MMME, and MMPE at 10° and 90° knee flexion, there was a significant positive correlation between percentage distance and improvement of MMPE at 90° knee flexion. Conclusion: This study demonstrated that the nearer the tibial tunnel position to the anatomic attachment of the MM posterior root, the more effective the reduction in MMPE at 90° knee flexion. Our results emphasize that an anatomic tibial tunnel should be created in the MM posterior root to improve the postoperative MMPE and protect the articular cartilage in a knee flexion position. Placement of an anatomic tibial tunnel significantly improves the MMPE at 90° of knee flexion after MM posterior root pullout repair. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Bone defects in the tibial tunnel for anterior cruciate ligament (ACL) reconstruction can cause adverse events. The unidirectional porous tricalcium β-phosphate (UDPTCP) has the potential to be used as a filling substitute for bone defects. In this case series, we present the first nine cases in which UDPTCP was used as a bone substitute in the tibial tunnel during ACL reconstruction. The patients comprised six males and three females, with an average age of 32 years (range: 16-50 years). A cylindrical UDPTCP measuring 10 x 20 mm was molded to fit the tibial tunnel and then implanted. At the one-year postoperative follow-up, none of the patients demonstrated any complications, and bone remodeling was observed on radiographs. Therefore, UDPTCP may provide a safe and reliable filling substitute for the tibial tunnel in ACL reconstruction., Competing Interests: The authors have declared financial relationships, which are detailed in the next section., (Copyright © 2024, Watanabe et al.)

Remnant preserving Anterior Cruciate Ligament (ACL) reconstruction requires the graft to be passed through the remnant ACL stump. This requires knowledge of the native alignment of the ACL. We investigated the alignment and orientation compared directly to the tibial plateau on Magnetic Resonance Imaging. We assessed if current equipment is adequate for anatomical reconstruction. 50 MRI scans with intact ACL and PCL were reviewed. Measurements were taken of; a) angle of ACL and tibial plateau in the sagittal plane, b) angle of ACL and tibial plateau in the coronal plane, c) position of ACL insertion into tibia as percentage of anterior-posterior width, d) position of ACL insertion into tibia as percentage of medio-lateral width. Statistical analysis included intra and interobserver agreement. Commonly used tibial guides were assessed for range of angles possible in use. The mean results for each measurement (+/− standard deviation) were; a) 45°(4.4°), b) 69°(5.5°), c) 37.2%(5.5%) d) 47.4%(1.5%). Intra-observer and inter-observer reliability were measured with satisfactory values. Not all tibial guides were able to produce an angle <45°. Our study is the first comparing the angle of inclination of the ACL directly with the tibial plateau. We demonstrate the angle in the sagittal plane is lower than reported previously. This data can be used in planning the tibial tunnel using remnant preserving techniques, to orientate in the natural alignment of the ACL. Not all reconstruction systems include options to align at the lower than previously thought natural angle of the ACL. III. [ABSTRACT FROM AUTHOR]

BACKGROUND: Accuracy and repeatability of bone tunnel in anterior cruciate ligament reconstruction has been a difficult point in surgery. As a new navigation technology, electromagnetic navigation system can realize three-dimensional positioning in application, hoping to make up for the mistakes made by surgeons. OBJECTIVE: To evaluate the feasibility and accuracy cl a new electromagnetic navigation system in anterior cruciate ligament reconstruction. METHODS: Totally 30 cases of fresh frozen knee joint were treated with anterior cruciate ligament amputation to prepare knee joint specimens with anterior cruciate ligament rupture. They were randomly divided into two groups, using magnetic channel navigation combined with arthroscopy (navigation group) and traditional arthroscopy (control group). Postoperative lateral radiography of knee joint was performed to observe the exit position of bone tunnel in two groups, to measure the position of the middle cl the tibial tunnel on the tibial plateau, to measure the α angle between the Blumensaat line and the axis of the tibial tunnel, aid ID measure the position of the femoral tunnel on the Blumensaat line. RESULTS AND CONCLUSION: (1) In the navigation group. the lateral X-ray radiographs of knee joint extension showed that the front edge of all tibial tunnels was slightly behind of Blumensaat line, avoiding intercondylar collision. In control group, two cases were located slightly ahead of Blumensaat line. (2) The distance (a) between the Blumensaat line at the level of tibial plateau and the front edge of the tibial tunnel, the ratio of a to width of tibial plateau anteroposterior diameter ( c) and alpha angles of tibial tunnel were smaller in the navigation group than in the control group (P < 0.05). This increased the accuracy of tibial tunnel positioning. (3) There was no significant difference in the location of the tibial tunnel between the two groups (P=0.323). However, the range of the central position of the tunnel (38.1%-53.8%) was slightly lower in the navigation group than that in the control group (30.4%-56.4%). The range of a distance (0.1-3.2 mm) in the navigation group was smaller than that in the control group (-2.1-5. 7 mm), and the location of bone marrow tract was more stringent, which increased the repeatability of location tibial tunnel. (4) The position cl femoral tunnel was in the position of the posterior upper quadrant (4/4) in all navigation groups and in 13 cases of the control group. The position of femoral tunnel in the navigation group was more backward compared with the control group (P=0.001 ). The femoral tunnel in the navigation group could ensure the stability of the knee. (5) In the cadaveric knee joint experiment, magnetic navigation technology can be used to assist the location of bone tunnel in anterior cruciate ligament reconstruction, increase the accuracy and repeatability of bone tunnel, but there are still artificial and magnetic channel navigation system errors, which still need ID be improved in clinical application. [ABSTRACT FROM AUTHOR]