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Two-dimensional (2D) MXenes have attracted significant attention in electromagnetic interference (EMI) shielding applications due to their unique properties, such as excellent metallic conductivity, high surface area, 2D geometry, tunable surface chemistry, and solution processability. In this study, we present a simple and versatile way for introducing multiple internal interfaces into the Ti3C2T x MXenes using insulating graphene oxide (GO) intercalants to enhance internal scattering, resulting in improved absorption loss and EMI shielding effectiveness (SE). Amine-functionalized MXene flakes exhibit a positive surface charge, while GO flakes have a negative charge at acidic pH levels. The functionalized MXene and GO flakes electrostatically self-assemble to form 2D/2D heterostack of MXene/GO nanosheets, and simultaneously generate multiple internal interfaces with significant impedance mismatch. The 2D/2D alternating heterostack of MXene/GO enhances the internal scattering of incident EM waves. Interestingly, despite their inferior electrical conductivity, the MXene/GO heterostack films exhibit higher EMI SE values than the randomly mixed hybrid films, and even outperform pristine MXene with larger electrical conductivity. This enhancement is attributed to enhanced absorption of electromagnetic waves resulting from strong internal scattering at the multiple internal interfaces in the heterostack film.

Graphene fiber is emerging as a new class of carbon-based fiber with distinctive material properties particularly useful for electroconductive components for wearable devices. Presently, stretchable and bendable graphene fibers are principally employing soft dielectric additives, such as polymers, which can significantly deteriorate the genuine electrical properties of pristine graphene-based structures. We report molecular-level lubricating nanodiamonds as an effective physical property modifier to improve the mechanical flexibility of graphene fibers by relieving the tight interlayer stacking among graphene sheets. Nanoscale-sized NDs effectively increase the tensile strain and bending strain of graphene/nanodiamond composite fibers while maintaining the genuine electrical conductivity of pristine graphene-based fibers. The molecular-level lubricating mechanism is elucidated by friction force microscopy on the nanoscale as well as by shear stress measurement on the macroscopic scale. The resultant highly bendable graphene/nanodiamond composite fiber is successfully weaved into all graphene fiber-based textiles and wearable Joule heaters, proposing the potential for reliable wearable applications.

The present study aimed to examine and compare the effects of a rehabilitation exercise (RE) using neuromuscular electrical stimulation (NMES) and blood flow restriction (BFR) on muscle function and knee functional abilities in patients who underwent anterior cruciate ligament reconstruction (ACLR). A total of 45 patients who underwent ACLR (28.76 ± 0.8 years; 34 males and 11 females) were retrospectively divided into three groups: control (CON, n = 15), NMES (n = 15), and BFR (n = 15). All participants carried out the RE program for 60 min, thrice a week for 12 weeks. The Lysholm score, International Knee Documentation Committee (IKDC) subjective score, thigh circumference at 5 cm from the knee joint, Y-balance posterior medial, and lateral significantly increased in all groups via intervention (p < 0.05). However, NMES showed a higher thigh circumference at 15 cm from the knee joint than CON via intervention (p < 0.05), and the strength and endurance of quadriceps femoris and hamstrings and Y-balance anterior showed a significant increase via intervention in NMES and BFR compared with CON (p < 0.05). In conclusion, we confirmed that RE using NMES and BFR effectively enhances muscle function and balance in ACLR patients.

An effective pathway to build macroscopic scale functional architectures bearing diverse structural dimensions is one of the critical challenges in the two-dimensional (2D) MXene research area. Unfortunately, assembling MXene without adhesive binder is largely limited due to its innate brittle nature and the relatively weak inter-flake van der Waals contact, in contrast to other mechanically compliant 2D materials such as graphene. Herein, an electrochemical self-assembly of pure Ti3C2Tx MXenes is presented for functional multidimensional MXene structures, effectively driven by layer-by-layer spontaneous interfacial reduction at metal template surfaces and subsequent defunctionalization. A three-dimensional open porous aerogel as well as 2D highly stacked thin film structures could be readily obtained in this approach, along with largely enhanced electrical properties induced by spontaneous removal of charge-trapping oxygen functional groups. Accordingly, supercapacitors and electromagnetic interference shielding films based on the multidimensional assembly demonstrate excellent performances.

Introduction: The goal in treating anterior cruciate ligament (ACL) injury, especially in revision cases is to return to sports activity by regaining dynamic postural stability. Additional anterolateral ligament reconstruction (ALLR) is gaining attention to achieve this goal. The purpose was to evaluate the effects of additional ALLR in revision ACL reconstruction (RACLR). Methods: Patients who underwent RACLR between July 2015 and June 2018 were enrolled. The exclusion criteria were less than the 1-year follow-up, age older than 45 years, concomitant multiple ligament injuries, contralateral knee injury, subtotal or total meniscectomized state, and cartilage lesions worse than Outerbridge grade 3. Thirty-nine patients (20 patients; RACLR only (Group A), 19 patients; RACLR with additional ALLR (Group B)) were included. Clinical scores, isokinetic strength test, single-leg-hop for distance test (SLHDT), and Y-balance test (YBT) were checked preoperatively and 1-year postoperatively.Results: Limb symmetry index values in YBT showed significantly better results in Group B 1-year postoperatively, although there were no differences preoperatively between groups. Regarding clinical scores, isokinetic strength tests, and SLHDT, there were no differences between groups preoperatively or 1-year postoperatively.Conclusion: Additional ALLR in RACLR helped patients gain better dynamic postural stability at 1-year postoperative follow-up.

To compare the clinical and radiologic outcomes and arthroscopic findings of proximal tibial osteotomy (PTO) alone versus PTO combined with medial meniscal posterior root repair (MMPRR).Between October 2010 and September 2016, patients who underwent PTO and second-look arthroscopy at a minimum of 24 months postoperatively were reviewed. Patients were divided into group I (isolated PTO), group P (PTO with MMPRR using the pull-out technique), and group F (PTO and MMPRR using the side-to-side repair method). The subjective knee scores were assessed. Radiologic evaluation was based on the Kellgren-Lawrence grade. Healing of medial meniscal posterior root tears (good/loose/scar tissue/failed) and cartilage regeneration (excellent/good/poor) were assessed by arthroscopic examination.Mean clinical follow-up duration of group I (n = 22), P (n = 25), and F (n = 24) was 28.5 ± 5.7, 27.9 ± 6.2, and 26.3 ± 5.3 months, respectively. At final follow-up, Lysholm score, International Knee Documentation Committee subjective score, and Tegner activity scale significantly improved in all groups (P.001), and subjective scores did not differ among the groups. The Kellgren-Lawrence grade progression showed no significant differences among 3 groups (P = .461). Good healing of medial meniscal posterior root tears was found in 24% and 12.5% of patients in groups P and F, respectively, and 0 in group I; there were significant differences between groups I and P (P.001) and groups I and F (P.001). Excellent cartilage regeneration in the medial femoral condyle and medial tibial plateau was found in 13.6% and 9.1% in group I, 24% and 12% in group P, and 16.7% and 8.3% in group F, respectively, without significant differences.Concurrent MMPRR during PTO appears to improve the arthroscopic appearance (healing of MMRPTs and cartilage regeneration) during second-look arthroscopy. However, concurrent MMPRR does not significantly improve clinical and radiologic outcomes at short-term follow-up.Level III, retrospective comparative study.

Two-dimensional (2D) MXene has shown enormous potential in scientific fields, including energy storage and electromagnetic interference (EMI) shielding. Unfortunately, MXene-based material structures generally suffer from mechanical fragility and vulnerability to oxidation. Herein, mussel-inspired dopamine successfully addresses those weaknesses by improving interflake interaction and ordering in MXene assembled films. Dopamine undergoes in situ polymerization and binding at MXene flake surfaces by spontaneous interfacial charge transfer, yielding an ultrathin adhesive layer. Resultant nanocomposites with highly aligned tight layer structures achieve approximately seven times enhanced tensile strength with a simultaneous increase of elongation. Ambient stability of MXene films is also greatly improved by the effective screening of oxygen and moisture. Interestingly, angstrom thick polydopamine further promotes the innate high electrical conductivity and excellent EMI shielding properties of MXene films. This synergistic concurrent enhancement of physical properties proposes MXene/polydopamine hybrids as a general platform for MXene based reliable applications.

Graphene fibers (GFs) are promising elements for flexible conductors and energy storage devices, while translating the extraordinary properties of individual graphene sheets into the macroscopically assembled 1D structures. We report that a small amount of water addition to the graphene oxide (GO) N-methyl-2-pyrrolidone (NMP) dispersion has significant influences on the mesophase structures and physical properties of wet-spun GFs. Notably, 2 wt % of water successfully hydrates GO flakes in NMP dope to form a stable graphene oxide liquid crystal (GOLC) phase. Furthermore, 4 wt % of water addition causes spontaneous planarization of wet-spun GFs. Motivated from these interesting findings, we develop highly electroconductive and mechanically strong flat GFs by introducing highly crystalline electrochemically exfoliated graphene (EG) in the wet-spinning of NMP-based GOLC fibers. The resultant high-performance hybrid GFs can be sewn on cloth, taking advantage of the mechanical robustness and high flexibility., A small amount of water can hydrate graphene oxide dispersed in organic solvents, resulting in formation of a liquid crystal phase and spontaneous rearrangement of graphene fibers in a flat geometry.

Purpose The purpose of this study was to evaluate the clinical efficacy and safety of treating patients with a cartilage defect of the knee with microfractures and porcine-derived collagen-augmented chondrogenesis technique (C-ACT). Methods One hundred participants were randomly assigned to the control group (n = 48, microfracture) or the investigational group (n = 52, C-ACT). Clinical and magnetic resonance imaging (MRI) outcomes were assessed 12 and 24 months postoperatively for efficacy and adverse events. Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) assessment was used to analyze cartilage tissue repair. MRI outcomes for 50% defect filling and repaired tissue/reference cartilage (RT/RC) ratio were quantified using T2 mapping. Clinical outcomes were assessed using the visual analogue scale (VAS) for pain and 20% improvement, minimal clinically important difference (MCID), and patient acceptable symptom state for Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee score. Results MOCART scores in the investigation group showed improved defect repair and filling (P = .0201), integration with the border zone (P = .0062), and effusion (P = .0079). MRI outcomes showed that the odds ratio (OR) for ≥50% defect filling at 12 months was statistically higher in the investigation group (OR 3.984, P = .0377). Moreover, the likelihood of the RT/RC OR becoming ≥1 was significantly higher (OR 11.37, P = .0126) in the investigation group. At 24 months postoperatively, the OR for the VAS 20% improvement rate was significantly higher in the investigational group (OR 2.808, P = .047). Twenty-three patients (52.3%) in the control group and 35 (77.8%) in the investigation group demonstrated more than the MCID of KOOS pain from baseline to 1 year postoperatively, with a significant difference between groups (P = .0116). Conclusion In this multicenter randomized trial, the addition of C-ACT resulted in better filling of cartilage defect of the knee joint. Level of Evidence Level Ⅰ, Multicenter Randomized Controlled Trial

Background: Few studies have reported the healing process of anterolateral ligament (ALL) injuries. Purpose/Hypothesis: This study investigated the healing status of ALL injuries after primary anterior cruciate ligament (ACL) reconstruction (ACLR). Additionally, we investigated the association between the healing status of ALL injuries and associated lesions such as osseous lesions and meniscal tears occurring at the time of an ACL rupture. We hypothesized that acute ALL injuries show a high rate (more than two-thirds) of healing at the 1-year follow-up after ACLR and that concomitant lesions observed at the time of an ACL rupture affect the healing status of the ALL. Study Design: Case-control study; Level of evidence, 3. Methods: We retrospectively investigated patients with ALL injuries who underwent primary ACLR between March 2015 and February 2017. Using magnetic resonance imaging (MRI), we evaluated the features of ALL injuries and concomitant lesions, and MRI was performed at the 1-year follow-up to assess the healing status of the ALL. We investigated the association between the healing status of the ALL and concomitant lesions observed at the time of an ACL rupture. A subjective assessment was performed using the Lysholm score, International Knee Documentation Committee subjective score, and Tegner activity scale. Objective tests included an isokinetic strength assessment and functional performance testing. Results: With respect to the severity of ALL injuries, of 54 patients, a complete rupture occurred in 16 (29.6%) of the 54 patients and a partial rupture in 38 (70%). A significant association was observed between the severity of ALL injuries and bone contusions (lateral tibial plateau and medial tibial plateau [MTP]) and meniscus ramp lesions (Fisher exact test: P = .023, .012, and .023, respectively). Good and partial healing of the ALL occurred in 16 (29.6%) and 23 (42.6%) of 54 patients, respectively. Scar formation occurred in 12 (22.2%), and nonvisualization of the ALL was observed in 3 (5.6%) of 54 patients. Poor healing of the ALL was associated with preoperative MTP bone contusions and a high-grade pivot shift. Multivariate analysis showed that an MTP bone contusion was an independent risk factor associated with poor healing of the ALL. Among the functional tests performed, significant differences were observed between the good and poor healing groups with respect to the carioca test ( P = .039). The good healing group (n = 16) showed a negative pivot shift at the last follow-up, whereas 5 (13.2%) of the patients from the poor healing group (n = 38) showed a positive pivot shift, including 2 (5.3%) with a high-grade pivot shift. Conclusion: Approximately 70% of acute ALL injuries showed poor healing at the 1-year follow-up. Poor healing of ALL injuries was significantly associated with preoperative MTP bone contusions and a high-grade pivot shift. Therefore, a careful assessment of posteromedial bone contusions at the time of an ACL rupture is warranted, particularly in patients with a high-grade pivot shift.

Graphene-fiber (GF) supercapacitors have attracted significant research attention in the field of wearable devices. However, there is still a need for active materials with high energy density. Transition Metal Nitrides (TMNs) are promising candidates for this purpose compared with conventional Transition Metal Oxides (TMOs) or conducting polymers (CPs) owing to their higher electrical conductivity, stability and relevant electrochemical properties. We have successfully integrated Tungsten Nitride (WN) with reduced graphene oxide fibers (rGOF) and developed high-performance hybrid fiber (WN-rGOF) supercapacitors. These hybrid supercapacitors attained a high capacitance of 16.29 F cm-3 at 0.05 A cm-3 and an energy density of 1.448 mW h cm-3, which is 7.5 and 1.75 times higher than those of the pure rGOF supercapacitor and the Tungsten Oxide/rGO hybrid fiber (WO3-rGOF) supercapacitor, respectively. The energy density readily increased up to 2.896 mW h cm-3 when three WN-rGOF supercapacitors were connected in series. The WN-rGOF supercapacitor also showed high capacitance retention of 84.7% after 10 000 cycles along with appreciable performance under severe mechanical deformation.

Two-dimensional (2D) materials are promising components for defect passivation of metal halide perovskites. Unfortunately, commonly used polydisperse liquid-exfoliated 2D materials generally suffer from heterogeneous structures and properties while incorporated into perovskite films. We introduce monodisperse multifunctional 2D crystalline carbon nitride, poly(triazine imide) (PTI), as an effective defect passivation agent in perovskite films via typical solution processing. Incorporation of PTI into perovskite film can be readily attained by simple solution mixing of PTI dispersions with perovskite precursor solutions, resulting in the highly selective distribution of PTI localized at the defective crystal grain boundaries and layer interfaces in the functional perovskite layer. Several chemical, optical, and electronic characterizations, in conjunction with density functional theory calculations, reveal multiple beneficial roles from PTI: passivation of undercoordinated organic cations at the surface of perovskite crystal, suppression of ion migration by blocking diffusion channels, and prevention of hole quenching at perovskite/SnO

Meniscal radial tears are equivalent to the meniscectomized state. However, successful healing rates by current repair methods for meniscal radial tears are still not satisfactory. Several suture configurations that could approximate the tear gap and stabilize meniscal tissue have been developed to overcome the shortcomings of simple horizontal stitches and cross stitches. The hybrid stitch method, composed of horizontal stitches and vertical stitches, has been introduced. This method can provide stable fixation because the vertical stitches suture the bundle of circumferential fibers, and the vertical stitches act as rip stops for the horizontal stitches. However, it is still challenging to heal meniscal radial tears in avascular areas or complex tears. In treating radial tears, it is important not only to improve suture mechanics but also to promote biologic healing potential.

A complete radial tear of the meniscus posterior root, which can cause a functional state of total meniscectomy via loss of hoop tension by disrupting the critical circumferential fibers, requires that the torn root should be managed. In the root tear, conservative treatment or meniscectomy have been considered the “traditional” treatment. However, current interest in root repair has been increased, because repair of meniscal root has a positive effect on functional restoration of the meniscus by restoring hoop tension. A recent international consensus statement has acknowledged the effectiveness of root repair with evidence taken from biomechanical and clinical studies with goals of restoring the structure and function of the meniscus. However, there are several challenges to overcome to get good clinical results. This chapter demonstrates surgical techniques of root repair and reviews of their clinical results.

Background: The goals of operative treatment for the adolescent athlete with unstable osteochondritis dissecans (OCD) lesion are rigid fixation and prevention of recurrence. Purpose: To evaluate clinical and radiological outcomes of internal fixation of lateral trochlear groove OCD with simultaneous lateral retinacular lengthening. Study Design: Case series; Level of evidence, 4. Methods: Adolescent athletes who had undergone internal fixation and simultaneous lateral retinacular lengthening for an unstable OCD lesion of the lateral trochlear groove were retrospectively reviewed. Subjective assessments included the Lysholm score, International Knee Documentation Committee (IKDC) subjective score, Tegner activity scale, and an athletic questionnaire. Functional tests included isokinetic muscle strength, single-leg hop for distance, single-leg vertical jump, and Y-balance. Pre- and postoperative radiographs and magnetic resonance images were reviewed. Results: The mean ± SD age of the 17 patients included in this study was 15.9 ± 0.9 years; last clinical follow-up duration was 37.7 ± 8.1 months. At the last follow-up, the Lysholm score improved from 68.7 ± 15.3 to 93.4 ± 12.4 and the IKDC subjective score from 60.2 ± 14.7 to 88.7 ± 12.7 ( P < .001). The mean Tegner activity scale score was 9.4 ± 0.5 before injury and 8.9 ± 1.2 at the last follow-up ( P = .059). The limb symmetry indices of isokinetic muscle strength, single-leg hop for distance, single-leg vertical jump, and Y-balance improved at the last follow-up; the mean limb symmetry index was ≥85% in each functional test. Regarding the athletic questionnaire, 16 (94.1%) patients were satisfied with the surgery. At the last follow-up, 2 patients had higher ability after returning to sports, 11 had the same ability, and 3 had lower ability than the preinjury level. Postoperative magnetic resonance imaging at 12-month follow-up showed that the OCD lesion appeared healed in 7 (41.2%) patients and partially healed in 9 (52.9%). Conclusion: Internal fixation of lateral trochlear groove OCD with simultaneous lateral retinacular lengthening in adolescent athletes achieved satisfactory clinical and radiological outcomes. Therefore, this combined surgical technique could be considered an effective treatment for lateral trochlear groove OCD, with a high rate of return to sport.

Varus alignment of the knee joint (varus5°) is known as a poor prognostic factor for medial meniscus root repair, and alignment correction is recommended in patients with varus deformity and medial meniscus root tears. However, simultaneous medial meniscus pull-out repair and high tibial osteotomy are technically demanding procedures due to the long surgical time, poor visualization, and breaking of the pull-out sutures during high tibial osteotomy procedures. In the present Technical Note, we will introduce a surgical method to perform 2 procedures simultaneously without technical difficulty. The main surgical techniques are as follows. (1) Release the superficial medial collateral ligament before arthroscopic medial meniscus pull-out repair, which secures sufficient working space and visualization. Therefore, the operation time could also be reduced by performing the arthroscopic procedure with the anterior portal. (2) Protect the pull-out sutures with an ENDOBUTTON reamer, which prevents pull-out sutures from breaking during the high tibial osteotomy procedure.

Background: It remains unclear whether lateral joint space narrowing without severe cartilage loss before meniscal allograft transplantation (MAT) affects clinical outcomes and graft extrusion. Hypothesis: Patients with greater preoperative joint space narrowing would show more graft extrusion, more osteoarthritis progression, and worse clinical outcomes than would those with less narrowing. Study Design: Case-control study; Level of evidence, 3. Methods: We retrospectively evaluated 61 patients who underwent lateral MAT and had a minimum follow-up of 4 to 5 years. The median preoperative joint space width (JSW) on Rosenberg view radiographs was used to classify patients into those with less joint space narrowing (JSW ≥3 mm; group A) and greater joint space narrowing (JSW Results: There were 31 patients in group A and 30 patients in group B; the mean follow-up time for all patients was 64.4 ± 10.3 months. All patients showed a significant preoperative to postoperative improvement in outcome scores ( P < .001 for all). The mean preoperative JSW was 3.8 ± 0.9 mm in group A and 2.3 ± 0.4 mm in group B ( P < .001). In group B, there was more graft extrusion on postoperative MRI scans (3.0 ± 0.9 vs 1.9 ± 0.6 mm, respectively; P < .001) and a higher proportion of patients with pathological graft extrusion at final follow-up (43.3% vs 12.9%, respectively; P = .011) compared with group A. At 1 year postoperatively, cartilage loss grade ≥3 was observed at the lateral femoral condyle in 3.2% and 20.0% of patients in groups A and B ( P = .053), respectively, and at the lateral tibial plateau in 3.2% and 30.0% of patients ( P = .006), respectively. There were moderate correlations between graft extrusion and preoperative absolute JSW ( r = –0.471; P < .001) and preoperative relative JSW ( r = –0.428; P = .001). Conclusion: Patients with less preoperative joint space narrowing had less graft extrusion and cartilage loss on 1-year postoperative MRI scans, as well as better radiological and clinical outcomes at midterm follow-up, compared with patients with greater preoperative narrowing.

An effective pathway to build macroscopic scale functional architectures bearing diverse structural dimensions is one of the critical challenges in the two-dimensional (2D) MXene research area. Unfortunately, assembling MXene without adhesive binder is largely limited due to its innate brittle nature and the relatively weak inter-flake van der Waals contact, in contrast to other mechanically compliant 2D materials such as graphene. Herein, an electrochemical self-assembly of pure Ti

To evaluate the mid-term outcomes of anatomic medial complex reconstruction in cases of serious medial knee instability. Between 2010 and 2013, 23 patients who underwent anatomic medial complex reconstruction with a minimum 5-year follow-up were included. The Lysholm score, International Knee Documentation Committee subjective knee form (IKDC SKF), and Tegner activity scale scores were evaluated. Clinical and functional tests included valgus and sagittal stress tests, isokinetic muscle strength test, single leg hop for distance test (SLDT), and single leg vertical jump test (SLVT). The mean follow-up duration was 77.2 ± 10.8 months. At final follow-up, the Lysholm score improved from 49.7 ± 10.2 to 93.4 ± 12.4; the IKDC SKF score, from 46.2 ± 8.7 to 90.5 ± 13.9; and median Tegner activity, from 5 (4–7) to 7 (4–10) (P

Background: Although the cause of rotational instability after revision anterior cruciate ligament reconstruction (ACLR) is multifactorial, the rationale of adding an extra-articular procedure is based on its ability to restrict rotational instability. Purpose: To assess the effect of anterolateral ligament (ALL) reconstruction on revision ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 87 patients who underwent revision ACLR between March 2011 and July 2014 with a follow-up of more than 3 years were included in this retrospective study. Patients were divided into the isolated revision ACLR group (group I, n = 45, from March 2011 to January 2013) or the revision ACLR in combination with ALL reconstruction group (group C, n = 42, from February 2013 to July 2014). Subjective knee assessments including the subjective International Knee Documentation Committee (IKDC) form, Lysholm score, Tegner activity scale, and Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI) scale were used. Clinical and functional tests were performed before surgery and at ≥6 months after surgery. All tests were usually completed at 36 months of follow-up. Results: The mean follow-up duration for groups I and C were 41.5 ± 8.2 and 38.2 ± 6.9 months, respectively ( P = .451). The subjective IKDC score, Tegner score, and ACL-RSI score were significantly better in group C compared with those in group I at the last follow-up (84.3 ± 18.5 vs 75.9 ± 19.2, 7.0 ± 0.8 vs 6.3 ± 0.7, and 69.5 ± 25.4 vs 51.9 ± 23.1, respectively), although they were not significantly different between the 2 groups at 12 months after surgery (79.2 ± 18.8 vs 76.7 ± 17.2, 6.7 ± 0.7 vs 6.5 ± 0.9, and 50.2 ± 24.6 vs 49.9 ± 25.1, respectively). There were no significant differences in KT-2000 arthrometer, isokinetic extensor strength, single-legged hop for distance, co-contraction test, or carioca test results between the 2 groups at the last follow-up ( P = .304, .068, .125, .056, and .066, respectively). Preoperatively, 43 (95.6%) patients in group I and 40 (95.2%) patients in group C had a grade 2 or 3 pivot shift ( P = .387). Postoperatively, 23 (53.5%) patients in group I and 38 (90.5%) patients in group C had a negative pivot shift ( P < .001). Group C showed a higher rate of return to the same level of sports activity than group I (57.1% vs 25.6%, respectively; P = .008), although there was no significant difference in the rate of return to any sports activity at the last follow-up (88.4% in group I vs 88.1% in group C; P = .713). Conclusion: Revision ACLR in combination with ALL reconstruction significantly reduced rotational laxity and showed a higher rate of return to the same level of sports activity than revision ACLR alone, although there were no significant differences in anterior laxity or functional test results between the 2 groups.

There are numerous evaluation tools used to assess subjective and objective status after knee injury or surgery. To evaluate appropriate results of treatment, methods of evaluation should include patient-oriented measures such as patient satisfaction and health-related quality of life (HRQOL), as well as outcomes of objective measures. Regarding subjective assessments, scoring systems developed and verified by experts group are widely used such as Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), and International Knee Document Committee (IKDC) subjective score. Since psychological factors in knee injuries are also an important factor, scales related to this have also been developed. Pre-existing objective assessments to evaluate knee function have limitations in determining real function, so efforts have been made to find more suitable methods of assessing the functional performance. It is becoming common to use the test battery to comprehensively determine the performance of sports activities as much as possible, and to measure them more concisely using the electronical equipment.

Graft extrusion after meniscal allograft transplantation (MAT) has been reported to be a distinct feature of transplanted meniscus and has not been resolved. Biomechanically, insufficient articular cartilage coverage generated by graft extrusion leads to failure in normal biomechanics of knee joint. Causes of the graft extrusion are uncertain, but there are possible explanations such as preoperative size measurement error, geometrically unmatched graft, mal-positioned graft, overtensioning of the graft suture, or soft tissue contracture at the meniscocapsular junction. However, literature on the rehabilitation strategy to reduce meniscal graft extrusion is lacking. Our delayed rehabilitation program aims to restrict the initial range of motion and minimize the load on the graft up to three months after MAT. We suggest that this delayed rehabilitation can provide a positive effect on mechanical stabilization and biological healing of the graft protecting the healing process at the relatively weak meniscocapsular attachment.

Outside-in technique is used popular nowadays as tibia tunnel-independent techniques ACL reconstruction along with transportal technique. Moreover, outside-in technique facilitates placement of the femoral tunnel in a center of the anatomic femoral origin of ACL. Recently, there has been growing interest in the substantial roles of the remnant of the ACL after a tear and attempts have been made to preserve remnant of the ACL after a tear. Among them, outside-in technique seems to be a more reliable and precise technique to achieve anatomic femoral origin of ACL with preserving the remnant bundle. In this chapter, the surgical technique and outcomes of ACL reconstruction using outside-in technique with/without remnant preservation are reviewed.

Return to sports (RTS) after anterior cruciate ligament (ACL) reconstruction is a critical treatment goal for most patients with ACL injuries. In spite of the importance of evaluating knee function in determining its timing of RTS, standardized evidence-based criteria which can be used to determine whether the patients can safely RTS is yet to be developed. As the importance of psychological factors has recently been emphasized whether to return to sports or not, psychological readiness should also be considered in the test battery. Therefore, a simple, reliable, objective, and comprehensive “goal-oriented” test battery is required to assess the possibility of RTS. This chapter aims to analyze the pros and cons of the preexisting functional tests including subjective and objective assessments and describe the future direction they need to develop.