Background: Meniscal allograft transplant (MAT) is an effective treatment for relieving symptoms and improving knee function in patients who experience symptomatic unicompartmental knee pain after a previous meniscectomy. However, the literature contains a paucity of studies assessing the survival rate and prognostic factors of soft tissue MAT. Purpose: To report the survivorship of a large, single-center cohort of consecutive patients treated with arthroscopic MAT using soft tissue technique and to investigate variables that could potentially influence failures and outcomes. Study design: Case series; Level of evidence, 4. Methods: Consecutive MAT procedures totaling 364 performed in a single institution between June 2004 and April 2019 were screened and assessed for eligibility. Subjective clinical scores (Lysholm score, Tegner activity scale, and visual analog score) were collected preoperatively and at 2, 5, 7, and 10 years of follow-up. Two survival analyses were performed using Kaplan-Meier curves, with surgical failure (defined as any graft revision) and clinical failure (defined as a Lysholm score <65 points) used as endpoints. Univariate analyses were performed using reoperations, surgical failure, clinical failure, and different demographic and surgical characteristics as endpoints. Results: A total of 324 consecutive patients were evaluated at a mean follow-up 5.7 ± 3.0 years. Of these, 189 (58%) underwent an associated surgical procedure. A total of 22 patients (6.8%) were considered to have experienced surgical failure, and no predictors of surgical failure were identified based on the relevant variables. When all patients were considered, a significant improvement in all of the patient-reported outcome measures was present between the preoperative assessment and the last follow-up ( P < .001), with no significant decrease over time. Moreover, 70 (21.6%) patients were considered to have experienced clinical failure; the need for concurrent cartilage procedures (odds ratio, 0.16; P = .001) and anterior cruciate ligament (ACL) reconstruction (odds ratio, 0.40; P = .059) were predictors of failure. Finally, a lower survival rate was reported in female patients compared with male patients (49% vs 69%, respectively; P = .007) and in patients who required cartilage surgery ( P = .014). In particular, patients who required cartilage surgery showed nearly half the survival rate compared with those with required no cartilage procedures at 10-year follow-up (36.4% vs 71%, respectively; P = .029). Conclusion: Female sex and the need to combine MAT with a cartilage procedure or ACL reconstruction could result in an increased rate of clinical failure at midterm follow-up.

➤ Posterior tibial slope (PTS) of ≥12° represents an important risk factor for both anterior cruciate ligament (ACL) injury and ACL reconstruction failure. ➤ PTS measurements can significantly differ on the basis of the imaging modality and the measurement technique used. PTS should be measured on strictly lateral radiographs, with a recommended proximal tibial length of 15 cm in the image. The PTS measurement can be made by placing 2 circles to define the proximal tibial axis, 1 just below the tibial tubercle and another 10 cm below it. PTS measurements are underestimated when made on magnetic resonance imaging and computed tomography. ➤ Slope-reducing osteotomies can be performed using a (1) supratuberosity, (2) tubercle-reflecting transtuberosity, or (3) infratuberosity method. The correction target remains a topic of debate. Although it is controversial, some authors recommend overcorrecting the tibial slope slightly to a range of 4° to 6°. For instance, if the initial slope is 12°, a correction of 6° to 8° should be performed, given the target tibial slope of 4° to 6°. ➤ Clinical outcomes following slope-reducing osteotomies have been favorable. However, potential complications, limited data with regard to the impact of slope-reducing osteotomies on osteoarthritis, and uncertainty with regard to the effects on the patellofemoral joint are notable concerns. ➤ Patients with complex deformities may need biplanar osteotomies to comprehensively address the condition.

Purpose: To assess the survival rate and associated risk factors of a wide cohort of patient’s underwent surgical treatment for posterior cruciate ligament (PCL)‐based multiligament knee injury (MLKI) at long‐term follow‐up and to investigate the long‐term patient’s reported outcomes (PROMS) and functional activity.Methods: All cases of PCL‐based MLKI performed at one single sport‐medicine institution were extracted and patient’s with a minimum 2 years of follow‐up included. VAS, Lysholm, KOOS, Tegner Activity level scores, the incidence and time of return to sport (RTS) and return to work (RTW) were collected before, after surgery and at final follow‐up. A multivariate logistic regression was performed to investigate the outcomes associated with the patient’s acceptable symptoms state (PASS) for each sub‐score of the KOOS. The Kaplan–Meier method with surgical failure (re‐operation to one of the reconstructed ligaments) as endpoint was used to perform the survivorship analysis for the entire cohort.Results: Forty‐two patients were included and evaluated at an average of 10 years. All PROMS significantly improved from pre‐ to post‐surgery (range η_p² 0.21–0.43, p < 0.05) except for the Tegner score which significantly improved from pre‐surgery and to final follow‐up (η_p² = 0.67, p < 0.001). RTW was achieved in the 95.2% after 2.4 ± 1.9 months. RTS was achieved in 78.6% after 6.7 ± 5.0 months. The higher number of surgeries were the significant negative predictors of PASS for the KOOS sub‐scales Sport (p = 0.040) and Quality of Life (p = 0.046), while the presence of meniscal lesions was a significant negative predictor of PASS only for the KOOS sub‐scale of Sport (p = 0.003). Six patients (14.3%) underwent reoperation and were considered as surgical failures. The global survivorship was 95.2%, 92.6%, 87.1%, and 74.7% at 2, 5, 12, and 15 years, respectively. The survivorship in patient undergoing PMC reconstruction surgery was significantly lower (p = 0.004; HR 7.1) compared to patients without a PMC lesion.Conclusion: Good‐to‐excellent PROMS could be obtained and maintained at long‐term follow‐up after surgery, with the higher number of surgeries and meniscal lesions as significant negative predictors of the PASS. Moreover, the presence of a PMC lesion significantly increases the risk of the PCL reconstruction failure.Level of evidence: III.

Purpose: The aim of the study was to evaluate the long‐term clinical results, reoperations, surgical failure and complications at a minimum of 20 year of follow‐up of the first 8 medial CMI scaffolds implanted by a single surgeon during a pilot European Prospective study.Methods: Seven (88%) out of 8 patients were contacted. The Cincinnati Score, VAS, and Lysholm score were collected. Moreover, magnetic resonance imaging (MRI) was performed on 4 patients at the last follow‐up. Complications, reoperations and failures were also investigated.Results: The average follow‐up was 21.5 ± 0.5 years. One patient underwent TKA after 13 years from CMI implantation; a second patient underwent valgus high tibial osteotomy 8 years after the index surgery and another patient underwent anterior cruciate ligament hardware removal at 21 years of follow‐up. At the final follow‐up, 3 patients were rated as “Excellent”, 1 as “Good” and 2 as “Fair” according to the Lysholm score. The Cincinnati score and the VAS were substantially stable over time. The MRI showed a mild osteoarthritis progression in 3 out of 4 patients according to the Yulish score, and the CMI signal was similar to the mid‐term follow‐up revealing 3 cases of myxoid degeneration and 1 case of normal signal with reduced scaffold size.Conclusion: The medial CMI is a safe procedure: satisfactory clinical results and a low failure rate could be expected even at a long‐term follow‐up. For this purpose, the correct indication as well as correcting axial malalignment and addressing knee instability at the time of the index surgery is mandatory. On the other hand, a mild osteoarthritis progression could be expected even after meniscus replacement.Level of evidence: IV.

Purpose: The aim of the present study was to trace knee position at the time of bone bruise (BB) and investigate how much this position departed from the knee biomechanics of an in vivo flexion–extension.Methods: From an original cohort of 62 patients, seven (11%) presented bicompartmental edemas and were included in the study. 3D models of bones and BB were obtained from MRI. Matching bone edemas, a reconstruction of the knee at the moment of BB was obtained. For the same patients, knee kinematics of a squat was calculated using dynamic Roentgen sterephotogrammetric analysis (RSA). Data describing knee position at the moment of BB were compared to kinematics of the same knee extrapolated from RSA system.Results: Knee positions at the moment of BB was significantly different from the kinematics of the squat. In particular, all the patients’ positions were out of squat range for both anterior and proximal tibial translation, varus–valgus rotation (five in valgus and two in varus), tibial internal–external rotation (all but one, five externally and one internally). A direct comparison at same flexion angle between knee at the moment of BB (average 46.1° ± 3.8°) and knee during squat confirmed that tibia in the former was significantly more anterior (p < 0.0001), more externally rotated (6.1 ± 3.7°, p = 0.04), and valgus (4.1 ± 2.4°, p = 0.03).Conclusion: Knee position at the moment of Bone bruise position was out of physiological in‐vivo knee range of motion and could reflect a locked anterior subluxation occurring in the late phase of ACL injury rather than the mechanism leading to ligament failure.Level of evidence: Level IV

Background: The accuracy of the coronal alignment corrections using conventional high tibial osteotomy (HTO) falls short, and multiplanar deformities of the tibia require consideration of both the coronal and sagittal planes. Patient-specific instrumentations have been introduced to improve the control of the correction. Clear evidence about customized devices for HTO and their correction accuracy lacks. Methods: The databases PUBMED and EMBASE were systematically screened for human and cadaveric studies about the use of customized devices for high tibial osteotomy and their outcomes concerning correction accuracy. Furthermore, a 3D-printed customized system for valgus HTO with three pilot cases at one-year follow-up was presented. Results: 28 studies were included. The most commonly used custom-made devices for HTO were found to be cutting guides. Reported differences between the achieved and targeted correction of hip-knee-ankle angle and the posterior tibial slope were 3° or under. The three pilot cases that underwent personalized HTO with a new 3D-printed device presented satisfactory alignment and clinical outcomes at one-year follow-up. Conclusion: The available patient-specific devices described in the literature, including the one used in the preliminary cases of the current study, showed promising results in increasing the accuracy of correction in HTO procedure.