[Treatment of Injuries to the Posterior Cruciate Ligament]. / Therapie von Verletzungen des hinteren Kreuzbandes.

Compared to the anterior cruciate ligament injury, the rupture of the posterior cruciate Ligament (PCL) is the rarer condition. A high healing potential is attributed to the PCL in the literature, which is why conservative therapy is also considered important in addition to surgical treatment 1. Posterior cruciate ligament rupture is often associated with concomitant injuries. Among other things, up to 70% of cases are associated with accompanying injuries to the posterolateral corner 2. The detection of concomitant injuries has a significant influence on the outcome, as isolated surgical PCL stabilization does not lead to satisfactory results in these cases.

A New Entity of Ramp Lesion Combined with Posterior Root Tear of the Medial Meniscus: A Case Report.

CASE: This report describes a new pattern of meniscal tear in an 18-year-old man after a knee sprain; he had undergone anterior cruciate ligament revision (ACL-R) 3 years earlier. He was diagnosed with an anterior cruciate ligament (ACL) graft rupture, a ramp lesion (Thaunat type 4), and a posterior root avulsion fracture of the medial meniscus (MM) (LaPrade type 5). He was treated successfully with an all-inside repair of the ramp lesion, a transtibial pull-out repair of the root tear, and ACL graft revision and anterolateral stabilization. CONCLUSION: This specific meniscal injury pattern should be recognized and documented, potentially warranting consideration as a new addition to Thaunat and LaPrade classifications as type 6.

Surgical approach on combined chronic patellar tendon and bicruciate knee ligament injury.

A combined injury of the patellar tendon and both the anterior and posterior cruciate ligaments is disabling. It directly affects knee kinematics and biomechanics, presenting a considerable surgical challenge. In this complex and uncommon injury, decision-making should take into account the surgeon's experience and consider one- or two-stage surgery, tendon graft, graft fixation, and rehabilitation protocol. This manuscript discusses the surgical approach based on a comprehensive understanding of the patellar tendon and bicruciate biomechanics to guide which structures should be reconstructed first, especially when a two-stage procedure is chosen.

A Biomimetic Osteochondral Scaffold Augmented With Filtered Bone Marrow Aspirate for the Treatment of Joint Surface Lesions in the Knee.

BACKGROUND: Multilayered osteochondral scaffolds are becoming increasingly utilized for the repair of knee joint surface lesions (KJSLs). However, the literature on predictive factors is rather limited. PURPOSE: To (1) evaluate the clinical outcomes and safety of a combined single-step approach using a biomimetic collagen-hydroxyapatite scaffold (CHAS) and filtered bone marrow aspirate (fBMA) for the treatment of KJSLs and (2) identify significant predictors of the treatment outcomes. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: All patients who underwent surgery because of a KJSL (size ≥1.5 cm2; International Cartilage Regeneration & Joint Preservation Society grades 3-4) using the combination above were selected from a hospital registry database (100 patients; minimum 2-year follow-up). Patient characteristics, medical history, knee joint and lesion status, intraoperative details, and cellular parameters of the injected fBMA were collected. The arthroscopic evaluation of chondral and meniscal tissue quality in all knee compartments was performed using the Chondropenia Severity Score. Treatment outcomes were determined clinically using patient-reported outcome measures (Knee Injury and Osteoarthritis Outcome Score, EuroQol-5 Dimensions-3 Levels, EuroQol-Visual Analog Scale, and Tegner Activity Scale) and by assessing the occurrence of serious adverse events and graft failure. Multivariable regression analysis was performed to identify significant predictors of the treatment outcomes. RESULTS: At a mean follow-up of 54.2 ± 19.4 months, 78 (87%) patients completed the questionnaires with significant improvements toward the baseline (P < .00625): KOOS Pain subscale from 62 ± 17 to 79 ± 18, KOOS Total score from 57 ± 16 to 70 ± 20, EuroQol-Visual Analog Scale from 61 ± 21 to 76 ± 16, EuroQol-5 Dimensions-3 Levels from 0.57 ± 0.20 to 0.80 ± 0.21, and Tegner Activity Scale from 2.8 ± 1.5 to 3.9 ± 1.9. The graft failure rate was 4%. A longer duration of preoperative symptoms, previous surgery, larger lesions, older age, and female sex were the main negative predictors for the treatment outcomes. The Chondropenia Severity Score and the number of fibroblast colony-forming units in fBMA positively influenced some of the clinical results and safety. CONCLUSION: A CHAS augmented with fBMA proved to be an adequate and safe approach for the treatment of KJSLs up to midterm follow-up. Based on the subanalysis of predictive factors, the surgical intervention should be performed in a timely and precise manner to prevent lesion enlargement, deterioration of the general knee cartilage status, and recurrent surgical procedures, especially in older and female patients. When a CHAS is used, the quantity of MSCs seems to play a role in augmentation. REGISTRATION: NCT06078072 (ClinicalTrials.gov identifier).

Quantitative evaluation of meniscus injury using synthetic magnetic resonance imaging.

BACKGROUND: Magnetic resonance imaging (MRI) can diagnose meniscal lesions anatomically, while quantitative MRI can reflect the changes of meniscal histology and biochemical structure. Our study aims to explore the association between the measurement values obtained from synthetic magnetic resonance imaging (SyMRI) and Stoller grades. Additionally, we aim to assess the diagnostic accuracy of SyMRI in determining the extent of meniscus injury. This potential accuracy could contribute to minimizing unnecessary invasive examinations and providing guidance for clinical treatment. METHODS: Total of 60 (n=60) patients requiring knee arthroscopic surgery and 20 (n=20) healthy subjects were collected from July 2022 to November 2022. All subjects underwent conventional MRI and SyMRI. Manual measurements of the T1, T2 and proton density (PD) values were conducted for both normal menisci and the most severely affected position of injured menisci. These measurements corresponded to the Stoller grade of meniscus injuries observed in the conventional MRI. All patients and healthy subjects were divided into normal group, degeneration group and torn group according to the Stoller grade on conventional MRI. One-way analysis of variance (ANOVA) was employed to compare the T1, T2 and PD values of the meniscus among 3 groups. The accuracy of SyMRI in diagnosing meniscus injury was assessed by comparing the findings with arthroscopic observations. The diagnostic efficiency of meniscus degeneration and tear between conventional MRI and SyMRI were analyzed using McNemar test. Furthermore, a receiver operating characteristic curve (ROC curve) was constructed and the area under the curve (AUC) was utilized for evaluation. RESULTS: According to the measurements of SyMRI, there was no statistical difference of T1 value or PD value measured by SyMRI among the normal group, degeneration group and torn group, while the difference of T2 value was statistically significant among 3 groups (P=0.001). The arthroscopic findings showed that 11 patients were meniscal degeneration and 49 patients were meniscal tears. The arthroscopic findings were used as the gold standard, and the difference of T1 and PD values among the 3 groups was not statistically significant, while the difference of T2 values (32.81±2.51 of normal group, 44.85±3.98 of degeneration group and 54.42±3.82 of torn group) was statistically significant (P=0.001). When the threshold of T2 value was 51.67 (ms), the maximum Yoden index was 0.787 and the AUC value was 0.934. CONCLUSIONS: The measurement values derived from SyMRI could reflect the Stoller grade, illustrating that SyMRI has good consistency with conventional MRI. Moreover, the notable consistency observed between SyMRI and arthroscopy suggests a potential role for SyMRI in guiding clinical diagnoses.

[Clinical study of electroacupuncture therapy on postoperative rehabilitation of patients with knee fractures].

OBJECTIVE: To investigate the effect of electroacupuncture therapy on postoperative rehabilitation training of patients with knee fractures. METHODS: Patients with knee fractures from July 2020 to July 2021 were randomly assigned to either the experimental group or a control group according to the double-blind principle. Both groups were given surgical treatment and postoperative conventional rehabilitation training. There were 40 cases in the control group, including 27 males and 13 females;the age ranged from 20 to 66 years old with an average of (36.46±6.29) years old, continuous passive motion (CPM) training was performed after operation. There were 40 patients in the experimental group, including 24 males and 16 females. The age ranged from 21 to 68 years old with an average of (37.62±7.08) years old, on the basis of the control group, electroacupuncture was given. After 4 weeks of intervention, the excellent rate of knee function score, visual analogue scale (VAS) before and after intervention, serum pain mediators, prostaglandin E (PGE), substance P (SP), bradykinin (BK), joint range of motion and quality of life were compared between the two groups. RESULTS: After 4 weeks of intervention, the Rasmussen score for knee function in the experimental group (24.15±1.36) scores was higher than that in the control group (21.25±2.20) scores (P<0.001). The VAS in the experimental group (2.04±0.51) scores was lower than that in the control group (2.78±0.60) after 4 weeks of intervention (P<0.05). Serum PGE (2.25±0.37) mg·L-1, SP (4.43±1.05) ng·ml-1, BK (2.67±0.68) ng·ml-1 in the experimental group were lower than those in the control group (3.91±0.44) mg·L-1, (6.12±1.37) ng·ml-1, (4.55±1.03) ng·ml-1 after 4 weeks of intervention(P<0.05);in the experimental group, the active knee flexion angle of the knee joint was (108.63±9.76)°, the active knee extension angle (-2.46±0.70)°, passive knee flexion angle (116.83±6.57)°, passive knee extension angle (1.44±0.38)° were better than control group (100.24±8.15)°, (-3.51±0.86)°, (111.04±8.22)°, (0.78±0.24)° (P<0.05);the experimental group's psychological score (73.12±5.08), physiological score (72.26±5.89), social function score (72.57±4.23), overall health score (75.12±5.16) were higher than that of the control group (68.49±4.13), (68.13±5.27), (69.04±3.42), and(70.88±3.97) respectvely(P<0.05). CONCLUSION: Electroacupuncture combined with CPM training after knee fracture surgery can significantly improve knee function and range of motion, reduce pain levels, and also improve quality of life and reduce the incidence of adverse events.

Acute Patellar Tendon Ruptures: An Update on Management.

Patellar tendon ruptures can be debilitating injuries. When incomplete, partial tears can be managed nonsurgically with immobilization and progressive rehabilitation. Although complete ruptures remain a relatively uncommon injury, they portend a high level of morbidity. Ruptures typically result from an acute mechanical overload to the extensor mechanism, such as with forced quadriceps contraction and knee flexion. However, chronically degenerated tendons are also predisposed to failure from low-energy injuries. Diagnosis can often be made clinically with recognition of a palpable defect to the tendon, localized patellar tendon tenderness, and inability to actively extend the knee. Diagnosis and surgical planning can be established with radiograph, ultrasonography, or magnetic resonance imaging. Surgical repair is the mainstay of treatment, and there have been many recent advances in repair technique, optimal reconstruction strategies, and supplemental fixation. Time to surgery for complete tears remains the most important prognosticator for success. Direct primary repair can be completed with transosseous tunnels, suture anchor repair, or end-to-end repair. Tendon reconstruction can be achieved with or without mechanical or biologic augments. Rehabilitation programs vary in specifics, but return to sport can be expected by 6 months postoperatively.

Diagnostic impacts on management of soft tissue injuries associated with tibial plateau fractures: A narrative review.

INTRODUCTION: Currently there is no consensus on the need for investigating knee ligamentous and meniscal injuries in a patient with a tibial plateau fracture. Consequently, many soft tissue injuries are likely undiagnosed and therefore untreated. The impact this has on long term knee outcomes is not well defined. We aimed to identify the impacts of various diagnostic methods on the management of meniscal injuries associated with tibial plateau fractures and evaluate the clinical outcomes. MATERIALS AND METHODS: We performed a systematic review using Pubmed, Medline, Embase, CINAHL and Cochrane following Cochrane guidelines. We included studies that operatively managed tibial plateau fractures and soft tissue injuries, which were diagnosed with either preoperative MRI, intra-operative arthroscopy or arthrotomy. RESULTS: 18 articles with 884 people, with a mean age of 46.4 years were included. Soft tissue injuries were detected on MRI (32-73%) and arthroscopy (12-70%), of which the most common were lateral meniscal injuries (7-64% of tibial plateau fractures). When identified by arthroscopy and arthrotomy, these injuries were almost always treated, either by repair or debridement. The clinical outcomes of these patients were poorly reported, with a heterogenous use of patient reported outcome measures, and follow up time points. There were no randomised trials or control groups for comparative analysis, however operative treatment yielded good to excellent outcomes. CONCLUSION: There is a high incidence of concomitant soft tissue injuries with tibial plateau fractures, particularly lateral meniscal injuries. There are 2 main approaches to meniscal injuries: surgeons who don't investigate, don't treat, whilst surgeons who do investigate often do surgically treat. Although studies that treated these injuries achieved good to excellent results, the currently available evidence doesn't confirm treatment superiority. As there is plausibility for better outcomes, randomised studies are needed to further investigate this clinical question.

Bilateral quadriceps tendon rupture: two injuries 6 years apart.

We present a case of a fit man in his 50s, with simultaneous bilateral quadriceps tendon repair of injuries sustained 6 years apart. Spontaneous closed ruptures of the quadriceps tendon are uncommon. Clinical data of a single case of bilateral quadriceps tendon injury with simultaneous repair was gathered via the patient, notes and surgeon. Diagnosis was primarily based on history and clinical examination. Suggestive features on the plain radiographic imaging were also present. Confirmation was attempted using ultrasonography but yielded conflicting reports. The patient was screened for any associated predisposing conditions that would preclude surgical intervention or increase risk of recurrence. Repairs were accomplished by employing a combination of suture anchors and transpatellar cerclage reinforcement. Apposition of the tendon to the superior patellar pole was successful although with decreased passive flexion on the neglected side (approximately 30°) compared with the acute (approximately 90°). Follow-up continues with postoperative rehabilitation.

Do Age and Timing Influence the Outcomes of Single-stage Reconstruction of Multiple Ligament Knee Injuries? 5-10 Years Follow Up.

OBJECTIVES: Multiple ligament knee injuries (MLKIs) are disruptive injuries, however, there are controversies in the results of acute and delayed reconstruction. Also, clinical outcomes between patients older or younger than 40 have not been compared in MLKIs. This study was designed to investigate the influence of age and timing of reconstruction on the outcomes of single-stage reconstruction of MLKIs. METHODS: The patients who underwent reconstruction of multiple injured ligaments because of MLKIs between May 2013 and July 2019 were added to the cohort. The postoperative complications, knee range of motion (ROM), Lysholm score, International Knee Documentation Committee (IKDC) 2000 score, Tegner activity level, patient satisfaction, and SF-36 score were compared between young (≤ 40 years old, n = 41) and old patients (n = 61); acute (≤ 3 weeks after injury, n = 75) and delayed reconstruction (n = 27), using Mann-Whitney U test or χ2 test. RESULTS: A total of 102 MLKI patients managed by single-stage multi-ligament reconstruction were retrospectively reviewed. Patients were followed up after surgery for a mean of 7.3 years (5.2-10.7 years). At the last follow-up, no significant difference was found in knee ROM, functional scores, and patient-reported outcomes between patients older or younger than 40; acute and delayed reconstruction (p > 0.05). The rate of complications in the delayed reconstruction group was higher than that of the acute reconstruction group (22.2% vs 5.3%, p < 0.05). The IKDC objective scores reached grade A in 63.7%-80.4% of patients, and grade B in 11.8%-23.5% patients. CONCLUSION: The single-stage reconstruction of MLKIs can obtain comparative long-term functional and objective outcomes regardless of patients older or younger than 40; acute and delayed reconstruction, however, delayed reconstruction is related to a high rate of postoperative complications.

Clinical and radiologic outcomes in patients with meniscal root tears.

BACKGROUND: Meniscal root tears can lead to early knee osteoarthritis and pain. This study aimed (1) to compare clinical and radiological outcomes between patients who underwent arthroscopic meniscal root repair after meniscal root tears and those who received non-surgical treatment, and (2) to identify whether baseline MRI findings could be potential predictors for future treatment strategies. METHODS: Patients with meniscal root tears were identified from our picture archiving and communication system from 2016 to 2020. Two radiologists reviewed radiographs and MRI studies using Kellgren-Lawrence (KL) grading and a modified Whole Organ MRI Scoring (WORMS) at baseline and follow-up. The median (interquartile range [IQR]) of follow-up radiographs and MRI studies were 134 (44-443) days and 502 (260-1176) days, respectively. MR images were assessed for root tear-related findings. Pain scores using visual analogue scale (VAS) and management strategies (non-surgical vs. arthroscopic root repair) were also collected. Chi-squared tests and independent t-tests were used to assess differences regarding clinical and imaging variables between treatment groups. Logistic regression analyses were performed to evaluate the associations between baseline MRI findings and each future treatment. RESULTS: Ninety patients were included. VAS pain scores were significantly (p < 0.01) lower after arthroscopic repair compared to conservative treatment (1.27±0.38vs.4±0.52) at the last follow-up visit with median (IQR) of 325 (180-1391) days. Increased meniscal extrusion (mm) was associated with higher odds of receiving non-surgical treatment (OR = 1.65, 95%CI 1.02-2.69, p = 0.04). The odds of having arthroscopic repair increased by 19% for every 1 mm increase in the distance of the tear from the root attachment (OR = 1.19, 95% CI: 1.05-1.36, p < 0.01). The odds of undergoing arthroscopic repair were reduced by 49% for every 1 mm increase in the extent of meniscal extrusion (OR = 0.51, 95% CI: 0.29-0.91, p = 0.02) as observed in the baseline MRI. CONCLUSIONS: Patients who underwent arthroscopic repair had lower pain scores than patients with conservative treatment in the follow-up. Distance of the torn meniscus to the root attachment and the extent of meniscal extrusion were significant predictors for arthroscopic repair in the next three weeks (time from the baseline MRI to the surgery date).

Rates of Subjective Failure After Both Isolated and Combined Posterior Cruciate Ligament Reconstruction: A Study From the Norwegian Knee Ligament Registry 2004-2021.

BACKGROUND: Outcomes after posterior cruciate ligament (PCL) reconstruction (PCLR) have been reported to be inferior to those of anterior cruciate ligament reconstruction. Furthermore, combined ligament injuries have been reported to have inferior outcomes compared with isolated PCLR. PURPOSE/HYPOTHESIS: The purpose of this study was to report on PCLR outcomes and failure rates and compare these outcomes between isolated PCLR and multiligament knee surgery involving the PCL. The hypothesis was that combined PCL injury reconstruction would have higher rates of subjective failure and revision relative to isolated PCLR. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients with primary PCLR with or without concomitant ligament injuries registered in the Norwegian Knee Ligament Registry between 2004 and 2021 were included. Knee injury and Osteoarthritis Outcome Score (KOOS) totals were collected preoperatively and at 2 years and 5 years postoperatively. The primary outcome measure was failure, defined as either a revision surgery or a KOOS Quality of Life (QoL) subscale score <44. RESULTS: The sample included 631 primary PCLR procedures, with 185 (29%) isolated PCLR procedures and 446 (71%) combined reconstructions, with a median follow-up time of 7.3 and 7.9 years, respectively. The majority of patients had poor preoperative knee function as defined by a KOOS QoL score <44 (90.1% isolated PCLR, 85.7% combined PCL injuries; P = .24). Subjective outcomes improved significantly at 2- and 5-year follow-up compared with preoperative assessments in both groups (P < .001); however, at 2 years, 49.5% and 46.5% had subjective failure (KOOS QoL <44) for isolated PCLR and combined PCLR, respectively (P = .61). At 5 years, the subjective failure rates of isolated and combined PCLR were 46.7% and 34.2%, respectively (P = .04). No significant difference was found in revision rates between the groups at 5 years (1.9% and 4.6%, respectively; P = .07). CONCLUSION: Patients who underwent PCLR had improved KOOS QoL scores relative to their preoperative state. However, the subjective failure rate was high for both isolated and multiligament PCLR. Within the first 2 years after surgery, patients who undergo isolated PCLR can be expected to have similar failure rates to patients who undergo combined ligament reconstructions.

Maximum outcome with minimal resources: report of a multiligamentous knee injury managed with 'modified confluent tunnel technique'.

Multiligamentous knee injuries (MLKIs) are rare and challenging to manage in many aspects. The injury requires prompt diagnosis, reconstruction of multiple ligaments, and management of associated neurovascular injuries. Another important aspect that surgeons should consider is resource availability. Successful management of a case of MLKI using the cost-effective 'modified confluent tunnel technique' is described in this case report. We used confluent tunnels for intra- and extra-articular ligament reconstructions at the femoral side. We incorporated the weave technique for medial collateral ligament (MCL) reconstruction, and Larson's technique for posterolateral corner (PLC) reconstruction in this construct, and augmented the anterior cruciate ligament (ACL) and posterior cruciate ligament reconstruction with the remaining PLC and MCL grafts, respectively. This was cost-effective and resulted in good functional outcomes. The technique also helped us to avoid tunnel convergence which is an expected complication in MLKI surgeries.

Editorial Commentary: Long-Term Outcomes of Autologous Osteochondral Transfer of the Knee Are Successful and Predicated Upon Appropriate Patient Selection.

Cartilage restoration techniques continue to grow in complexity, expanding from traditional marrow stimulation or isolated chondroplasty of chondral lesions to various grafting procedures. Microfracture can induce a less favorable biologic response that includes formation of type I fibrocartilage and development of subchondral cystic changes or sclerosis. Thus, chondral graft options that restore native type II hyaline cartilage are favored. Autologous osteochondral transfer is a favorable graft option because it provides native type II hyaline cartilage on an autologous subchondral scaffold that most closely emulates the native chondral environment, and clinical studies demonstrate better functional outcomes and return to sport compared with other cartilage grafting and bone marrow stimulation procedures. Patient factors, including sex, age, lesion location, lesion size, etiology, and preinjury function must be considered on a case-by-case basis before determining the best procedure for a given patient. In athletes, long-term functional outcomes, return to sport, and avoidance of arthroplasty are favorable in appropriately selected individuals. Patient selection is paramount.

Risk factors of failure results after double-bundle reconstruction with autogenous hamstring grafts for isolated posterior cruciate ligament rupture cases.

Posterior tibial translation (PTT) after double-bundle posterior cruciate ligament (PCL) reconstruction has sometimes occurred. Purpose of this study is to identify the risk factors for postoperative PTT after double-bundle PCL reconstruction with a hamstring autograft. Comparing the results of bilateral gravity sag view (GSV) at 12 months after surgery, over 5-mm PTT was defined as 'failure' in this study. Of 26 isolated PCL reconstruction cases, over 5-mm PTT was seen in 7 cases (group F: 9.57 ± 1.28 mm), and 19 cases had less than 5 mm (group G: 2.84 ± 1.29 mm). Age, sex, body mass index (BMI), preoperative GSV, posterior slope angle of the tibia, anterolateral bundle (ALB) and posteromedial bundle (PMB) graft diameters, and tibial tunnel diameter were evaluated. The two groups were compared with the 2 × 2 chi-squared test, the Mann Whitney U-test, and Spearman's rank correlation coefficient. Multivariate logistic regression analysis was also performed to determine the risk factor. Statistical significance was indicated as p < 0.01 for correlation with postoperative PTT, and as p < 0.05 for all other comparisons. Mean age (group G 31.8 ± 12.5 vs group F 34.9 ± 15.9 years), sex (male/female: 15/4 vs 3/4), BMI (25.6 ± 4.6 vs 24.9 ± 3.9 kg/m2), preoperative GSV (11.3 ± 2.2 vs 11.6 ± 2.9 mm), PMB diameter (5.37 ± 0.33 vs 5.36 ± 0.48 mm), and tibial tunnel diameter (9.32 ± 0.58 vs 9.29 ± 0.49 mm) showed no significant differences. ALB diameter was significantly greater in group G (7.0 ± 0.5 mm) than in group F (6.5 ± 0.29 mm; p = 0.022). There was also a significant difference in posterior tibial slope angle (group G 9.19 ± 1.94 vs group F 6.54 ± 1.45, p = 0.004). On Spearman rank correlation coefficient analysis, ALB diameter GSV (correlation coefficient: - 0.561, p = 0.003) and posterior tibial slope angle (correlation coefficient: - 0.533, p = 0.005) showed a significant correlation with postoperative PTT. Multivariate logistic regression analysis showed that ALB diameter (OR 19.028; 95% CI 1.082-334.6; p = 0.044) and posterior slope angle of tibia (OR 3.081; 95% CI 1.109-8.556; p = 0.031) were independently associated with postoperative PTT, respectively. In double-bundle PCL reconstruction with hamstring, smaller ALB graft diameter and lower (flatted) tibial slope angle were considered risk factors for postoperative PTT.

Perioperative outcomes in isolated versus multiligamentous anterior cruciate ligament reconstruction: a retrospective cohort analysis.

PURPOSE: The outcomes of anterior cruciate ligament reconstruction in the setting of multiligamentous knee injury (M-ACLR) have not been well characterized compared to isolated ACLR (I-ACLR). This study aims to characterize and compare short-term outcomes between I-ACLR and M-ACLR. METHODS: This is a retrospective cohort analysis of the American College of Surgeons National Surgical Quality Improvement Program database from 2005 to 2017. Current Procedural Terminology codes were used to identify and compare elective I- and M-ACLR patients, excluding patients undergoing concomitant meniscal or chondral procedures. Patient demographics and outcomes after I- and M-ACLR were compared using bivariate analysis. Multiple logistic regression analyzed if multiligamentous ACLR was an independent risk factor for adverse outcomes. RESULTS: There was a total of 13,131 ACLR cases, of which 341 were multiligamentous cases. The modified fragility index-5 was higher in multiligamentous ACLR (p < 0.001). Multiligamentous ACLR had worse perioperative outcomes, with higher rate of all complications (3.8%, p = 0.013), operative time > 1.5 h (p < 0.001), length of stay (LOS) ≥ 1 day (p < 0.001), wound complication (2.1%, p = 0.001), and intra- or post-op transfusions (p < 0.001). In multiple logistic regression, multiligamentous ACLR was an independent risk factor for LOS ≥ 1 (odds ratio [OR] 5.8), and intra-/post-op transfusion (OR 215.1) and wound complications (OR 2.4). M-ACLR was not an independent risk factor for any complication, reoperation at 30 days, readmission, urinary tract infection (UTI), or venous thromboembolism (VTE). CONCLUSION: M-ACLR generally had worse outcomes than I-ACLR, including longer LOS, need for perioperative transfusions, and wound complications.

[Posterolateral instability of the knee joint]. / Posterolaterale Instabilität des Kniegelenks.

The posterolateral corner of the knee is composed of a multilayered complex of ligamentous, musculotendinous, and capsular structures, which interact in a synergistic stabilizing manner with the central structures, particularly the posterior cruciate ligament. Injuries of the posterolateral corner are generally accompanied by rupture of the posterior cruciate ligament. Depending on the injured structures, injuries of the posterolateral corner result in posterolateral rotational instability alone (Fanelli A) or with lateral instability (Fanelli B/C). For rotational instability alone, isolated popliteus bypass is an effective procedure; with concomitant lateral instability in flexion, additional stabilization of the lateral collateral ligament is required. Most of the various available techniques are described as open reconstruction procedures. In recent years, arthroscopic techniques for posterolateral reconstruction have also been successfully developed.

10-Year Prospective Clinical and Radiological Evaluation After Matrix-Induced Autologous Chondrocyte Implantation and Comparison of Tibiofemoral and Patellofemoral Graft Outcomes.

BACKGROUND: Long-term outcomes in larger cohorts after matrix-induced autologous chondrocyte implantation (MACI) are required. Furthermore, little is known about the longer-term clinical and radiological outcomes of MACI performed in the tibiofemoral versus patellofemoral knee joint. PURPOSE: To present the 10-year clinical and radiological outcomes in patients after MACI and compare outcomes in patients undergoing tibiofemoral versus patellofemoral MACI. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Between September 2002 and December 2012, 204 patients who underwent MACI were prospectively registered into a research program and assessed preoperatively and at 2, 5, and 10 years postoperatively. Of these patients, 168 were available for clinical review at 10 years, with 151 (of a total of 182) grafts also assessed via magnetic resonance imaging (MRI). Patients were evaluated using the Knee injury and Osteoarthritis Outcome Score, a visual analog scale for pain frequency and severity, satisfaction, and peak isokinetic knee extensor and flexor strength. Limb symmetry indices (LSIs) were calculated for strength measures. Grafts were scored on MRI scans via the MOCART (magnetic resonance observation of cartilage repair tissue) system, with a focus on tissue infill and an overall MRI graft composite score. RESULTS: All patient-reported outcome measures improved (P < .0001) up to 2 years after surgery. Apart from the significant increase (P = .004) in the peak isokinetic knee extensor LSI, no other patient-reported outcome measure or clinical score had changed significantly from 2 to 10 years. At the final follow-up, 92% of patients were satisfied with MACI to provide knee pain relief, with 76% satisfied with their ability to participate in sports. From 2 to 10 years, no significant change was seen for any MRI-based MOCART variable nor the overall MRI composite score. Of the 151 grafts reviewed via MRI at 10 years, 14 (9.3%) had failed, defined by graft delamination or no graft tissue on MRI scan. Furthermore, of the 36 patients (of the prospectively recruited 204) who were not available for longer-term review, 7 had already proceeded to total knee arthroplasty, and 1 patient had undergone secondary MACI at the same medial femoral condylar site because of an earlier graft failure. Therefore, 22 patients (10.8%) essentially had graft failure over the period. At the final follow-up, patients who underwent MACI in the tibiofemoral (vs patellofemoral) joint reported significantly better Knee injury and Osteoarthritis Outcome Score subscale scores for Quality of Life (P = .010) and Sport and Recreation (P < .001), as well as a greater knee extensor strength LSI (P = .002). Even though the tibiofemoral group demonstrated better 10-year MOCART scores for tissue infill (P = .027), there were no other MRI-based differences (P > .05). CONCLUSION: This study reports the long-term review of a prospective series of patients undergoing MACI, demonstrating good clinical scores, high levels of patient satisfaction, and acceptable graft survivorship at 10 years. Patients undergoing tibiofemoral (vs patellofemoral) MACI reported better long-term clinical outcomes, despite largely similar MRI-based outcomes.

Clinical and Functional Outcomes of Documented Knee Dislocation Versus Multiligamentous Knee Injury: A Comparison of KD3 Injuries at Mean 6.5 Years Follow-up.

BACKGROUND: Previous research has found that the incidence of neurovascular injury is greatest among multiligamentous knee injuries (MLKIs) with documented knee dislocation (KD). However, it is unknown whether there is a comparative difference in functional recovery based on evidence of a true dislocation. PURPOSE: To determine whether the knee dislocation-3 (KD3) injury pattern of MLKI with documented tibiofemoral dislocation represents a more severe injury than KD3 MLKI without documented dislocation, as manifested by poorer clinical outcomes at long-term follow-up. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A multicenter retrospective cohort study was performed of patients who underwent surgical treatment for KD3 MLKI between May 2012 and February 2021. Outcomes were assessed using the International Knee Documentation Committee (IKDC) score, Lysholm score, Tegner activity scale, and visual analog scale (VAS) for pain. Documented dislocation was defined as a radiographically confirmed tibiofemoral disarticulation, the equivalent radiology report from outside transfer, or emergency department documentation of a knee reduction maneuver. Subgroup analysis was performed comparing lateral (KD3-L) versus medial (KD3-M) injuries. Multivariable linear regression was conducted to determine whether documented dislocation was predictive of outcomes. RESULTS: A total of 42 patients (25 male, 17 female) were assessed at a mean 6.5-year follow-up (range, 2.1-10.7 years). Twenty patients (47.6%) were found to have a documented KD; they reported significantly lower IKDC (49.9 vs 63.0; P = .043), Lysholm (59.8 vs 74.5; P = .023), and Tegner activity level (2.9 vs 4.7; P = .027) scores than the patients without documented dislocation. VAS pain was not significantly different between groups (36.4 vs 33.5; P = .269). The incidence of neurovascular injury was greater among those with documented dislocation (45.0% vs 13.6%; P = .040). Subgroup analysis found that patients with KD3-L injuries experienced a greater deficit in Tegner activity level than patients with KD3-M injuries (Δ: -3.4 vs -1.2; P = .006) and had an increased incidence of neurovascular injury (41.7% vs 11.1%; P = .042). Documented dislocation status was predictive of poorer IKDC (ß = -2.15; P = .038) and Lysholm (ß = -2.85; P = .007) scores. CONCLUSION: Patients undergoing surgical management of KD3 injuries with true, documented KD had significantly worse clinical and functional outcomes than those with nondislocated joints at a mean 6.5-year follow-up. The current MLKI classification based solely on ligament involvement may be obscuring outcome research by not accounting for true dislocation.

The Effect of Acute Knee Injuries and Related Knee Surgery on Serum Levels of Pro- and Anti-inflammatory Lipid Mediators and Their Associations With Knee Symptoms.

BACKGROUND: Despite an acute knee injury being a major risk factor for osteoarthritis, the factors that initiate and maintain this risk of longer-term knee symptoms are poorly understood. Bioactive lipids derived from omega-3 and -6 polyunsaturated fatty acids have key roles in the regulation of the inflammatory response and have been linked to joint damage and osteoarthritis pain in translational models. HYPOTHESIS: There would be associations between systemic levels of bioactive lipids and knee symptoms longitudinally after an acute knee injury and related knee surgery. STUDY DESIGN: Controlled laboratory study. METHODS: This study analyzed a subset of young, active adults who had sustained an acute knee injury (recruited via a surgical care pathway) and healthy age- and sex-matched controls. Surgery, if performed, was conducted after the baseline serum sample was taken and before the 3-month and 2-year visits. Liquid chromatography-tandem mass spectrometry of 41 bioactive lipids was carried out in sera of (1) 47 injured participants (median age, 28 years) collected at baseline (median, 24 days after injury), 3 months, and 2 years, along with the Knee injury and Osteoarthritis Outcome Score, and (2) age- and sex-matched controls. RESULTS: Levels of the omega-3 polyunsaturated fatty acids eicosapentaenoic acid (P≤ .0001) and docosahexaenoic acid (P≤ .0001) and the pro-resolving lipid mediators 17- and 14-hydroxydocosahexaenoic acid, and 18-hydroxyeicosapentaenoic acid were all significantly greater at baseline in injured participants compared with the later time points and also higher than in healthy controls (P = .0019 and P≤ .0001, respectively). Levels of pro-inflammatory prostaglandins E2 and D2, leukotriene B4, and thromboxane B2 were significantly lower at baseline compared with the later time points. Higher levels of 8,9-, 11,12-, and 14,15-dihydroxyeicosatrienoic acid (DHET) were cross-sectionally associated with more severe knee pain/symptoms according to the Knee injury and Osteoarthritis Outcome Score at 2 years (P = .0004, R2 = 0.251; P = .0002, R2 = 0.278; and P = .0012, R2 = 0.214, respectively). CONCLUSION: The profile of pro-resolving versus pro-inflammatory lipids at baseline suggests an initial activation of pro-resolution pathways, followed by the later activation of pro-inflammatory pathways. CLINICAL RELEVANCE: In this largely surgically managed cohort, the association of soluble epoxide hydrolase metabolites, the DHETs, with more severe knee symptoms at 2 years provides a rationale for further investigation into the role of this pathway in persisting knee symptoms in this population, including potential therapeutic strategies.