Comparison of the oncolytic activity of a replication-competent and a replication-deficient herpes simplex virus 1.

In 2015, the oncolytic herpes simplex virus 1 (HSV-1) T-VEC (talimogene laherparepvec) was approved for intratumoral injection in non-resectable malignant melanoma. To determine whether viral replication is required for oncolytic activity, we compared replication-deficient HSV-1 d106S with replication-competent T-VEC. High infectious doses of HSV-1 d106S killed melanoma (n = 10), head-and-neck squamous cell carcinoma (n = 11), and chondrosarcoma cell lines (n = 2) significantly faster than T-VEC as measured by MTT metabolic activity, while low doses of T-VEC were more effective over time. HSV-1 d106S and, to a lesser extent T-VEC, triggered caspase-dependent early apoptosis as shown by pan-caspase inhibition and specific induction of caspases 3/7, 8, and 9. HSV-1 d106S induced a higher ratio of apoptosis-inducing infected cell protein (ICP) 0 to apoptosis-blocking ICP6 than T-VEC. T-VEC was oncolytic for an extended period of time as viral replication continued, which could be partially blocked by the antiviral drug aciclovir. High doses of T-VEC, but not HSV-1 d106S, increased interferon-ß mRNA as part of the intrinsic immune response. When markers of immunogenic cell death were assessed, ATP was released more efficiently in the context of T-VEC than HSV-1 d106S infection, whereas HMGB1 was induced comparatively well. Overall, the early oncolytic effect on three different tumour entities was stronger with the non-replicative strain, while the replication-competent virus elicited a stronger innate immune response and more pronounced immunogenic cell death.

Higher conversion rate to knee arthroplasty in female patients following medial open-wedge high tibial osteotomy.

PURPOSE: Most studies about medial open-wedge high tibial osteotomy (HTO) reported outcomes without focusing on gender differences. Therefore, the study compared the long-term survival rate and postoperative subjective knee function after HTO in female versus male patients with symptomatic medial compartment knee osteoarthritis. METHODS: The data of three cohorts with long-term outcomes were analysed (n = 245; 32% females; age: 49 ± 7 years; Kellgren Lawrence Grade I 6.1%, II 32.7%, III 42.4%; IV 18.8%). The minimum follow-up was at least 6 years or an earlier conversion to total knee arthroplasty (TKA). The gender-specific survival rate after HTO was calculated after 5 and 10 years and compared using Kaplan-Meier analysis and the logrank test. Baseline characteristics and subjective knee function (International Knee Documentation Committee [IKDC]/Lysholm) were analysed between both genders. RESULTS: Forty of 78 (51.3%) women and 41 of 167 men (24.5%) underwent TKA. HTO survival in females was significantly lower (p = 0.0010). The 5- and 10-year survival rates were 85.9% and 62.6% for females and 93.4% and 77.7% for males. In females and males, from preoperative to the last follow-up, the IKDC (43 ± 15 to 58 ± 17; 47 ± 14 to 67 ± 18) and the Lysholm (42 ± 18 to 72 ± 18; 55 ± 22 to 77 ± 23) improved significantly (all p < 0.0001). Females had significantly lower preoperative and postoperative IKDC (p = 0.0438; p = 0.0035) and Lysholm scores (p = 0.0002; p = 0.0323). But the absolute improvements of the IKDC and Lysholm were not significantly different between genders. CONCLUSIONS: Females had higher conversion rates to TKA and lower knee function at the last follow-up. However, preoperative knee function was lower in females and the absolute improvement following HTO was similar for both genders. In general, females benefit from HTO to treat medial knee arthritis, and TKA could be postponed for half of female patients for more than 10 years. However, surgeons must be aware of the described inferior outcomes in females for realistic patient expectation management. LEVEL OF EVIDENCE: Level II.

Treatment of cartilage defects in the patellofemoral joint with matrix-associated autologous chondrocyte implantation effectively improves pain, function, and radiological outcomes after 5-7 years.

INTRODUCTION: The aim of the present study was to evaluate midterm outcomes 5-7 years after matrix-associated autologous chondrocyte implantation (MACI) in the patellofemoral joint. MATERIALS AND METHODS: Twenty-six patients who had undergone MACI using the Novocart® 3D scaffold were prospectively evaluated. Clinical outcomes were determined by measuring the 36-Item Short-Form Health Survey (SF-36) and International Knee Documentation Committee (IKDC) scores and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) values preoperatively and 3, 6, and 12 months, and a mean of 6 years postoperatively. At the final follow-up, the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was evaluated. RESULTS: Twenty-two patients with 23 focal cartilage defects (19 patella and four trochlea) were available for the final follow-up. The mean defect size was 4.0 ± 1.9 cm2 (range 2.4-9.4 cm2). All clinical outcome scores improved significantly until 5-7 years after MACI (SF-36 score, 61.2 ± 19.6 to 83.2 ± 11.6; P = 0.001; IKDC score, 47.5 ± 20.6 to 74.7 ± 15.5; P < 0.001; and WOMAC, 29.8 ± 15.7 to 8.2 ± 10.3; P < 0.001). The mean MOCART score was 76.0 ± 11.0 at the final follow-up. Nineteen of the 22 patients (86.4%) were satisfied with the outcomes after 5-7 years and responded that they would undergo the procedure again. CONCLUSION: MACI in the patellofemoral joint demonstrated good midterm clinical results with a significant reduction in pain, improvement in function, and high patient satisfaction. These clinical findings are supported by radiological evidence from MOCART scores. LEVEL OF EVIDENCE: IV-case series.

Double level osteotomy for medial osteoarthritis and bifocal varus malalignment has excellent short-term results while maintaining physiologic radiographic joint parameters.

PURPOSE: The purpose of this study was to prospectively evaluate the clinical and radiological results of double level osteotomy (distal femoral lateral closed wedge and proximal tibial medial open wedge) in medial osteoarthritis and varus malalignment due to bifocal deformity of femur and tibia. METHODS: From 2017 to 2019 all cases of DLO in osteoarthritic varus malaligned knees with bifocal deformity (femoral and tibial deformity) were prospectively enrolled into this observational therapeutic study. Evaluation was performed preoperatively, at six, twelve, 18 and 24 months with regard to survival (not requiring arthroplasty), functional outcome [subjective International Knee Documentation Committee score (IKDC), Oxford Knee Score (OKS), Knee Injury and Osteoarthritis Outcome score (KOOS) and Tegner Activity Scale], pain level (numeric rating scale), subjective satisfaction (rating 1-5), radiographic parameters on a pre-and postoperative full leg x-rays (mechanical axis, mechanical proximal tibial and distal femoral angles) and complications. For statistical evaluation student's t test, Mann-Whitney U test and Wilcoxon-signed-rank test were used. RESULTS: Fifty-two consecutive cases in 48 patients were enrolled in the study. Three cases were excluded, resulting in a follow-up rate of 94%. No arthroplasties were performed within follow-up. All functional outcome scores substantially and significantly increased as early as six months after the index procedure and further increased until final follow-up (p < 0.001). Pain level significantly decreased (p < 0.001). At final follow-up all patients stated that they would retrospectively undergo the operation again, and rated the result with 4.5 ± 0.6 out of 5 (3-5). Radiographic parameters were within physiological limits postoperatively. No severe complications occurred. CONCLUSIONS: Double level osteotomy has excellent short-term results while maintaining physiological radiographic parameters. Therefore, it should be an integral part and standard procedure in realignment surgery for monocompartimental osteoarthritis. LEVEL OF EVIDENCE: IV (prospective observational therapeutic study).

High prevalence of increased posterior tibial slope in ACL revision surgery demands a patient-specific approach.

PURPOSE: To determine the prevalence of an "increased posterior tibial slope (PTS)" (PTS ≥ 12°) in a population with one, two or ≥ three anterior cruciate ligament (ACL) graft insufficiencies. Furthermore, to investigate whether the prevalence of an increased PTS and the absolute PTS increases with an increasing number of ACL graft insufficiencies, as well as to determine the survival time of the first ACL graft. METHODS: Patients diagnosed with an ACL graft insufficiency between January 2021 and March 2022 were included. The PTS was measured using the proximal anatomical tibial axis on long lateral knee radiographs. Patients were divided into 3 groups depending on the number of ACL graft insufficiencies: group A (1 graft insufficiency), group B (2 graft insufficiencies) and group C (≥ 3 graft insufficiencies). The prevalence of increased PTS and absolute PTS between groups was compared alongside the survival of the first ACL graft between patients with or without increased PTS. RESULTS: Two-hundred and six patients (147 males/59 females) met the inclusion criteria. 73 patients showed an increased PTS [prevalence 35% [95% confidence interval (CI) (29%; 42%)]. 155 patients were found in category A, 42 patients in B and 9 patients in C. The prevalence of increased PTS for group A, B and C was, 32% [95% CI (25%; 40%)], 38% [95% CI (23%; 53%)] and 78% [95% CI (51%; 100%)], respectively. The prevalence of increased PTS and mean PTS did not increase significantly between group A and B. However, both parameters increased significantly between group A and C, and group B and C (p < 0.05). The survival time of the first ACL graft in patients with or without an increased PTS was 3 (interquartile range (IQR) 5) and 6 years (IQR 9), respectively (p < 0.05). CONCLUSION: There is a 35% prevalence of increased PTS in the studied ACL graft insufficient patient cohort. The survival of the first ACL graft is shorter in patients with an increased PTS. Surgeons should be aware of the high prevalence of increased PTS when consulting patients for revision ACL reconstruction as it is an important risk factor for recurrent instability.

[Attitudes toward digital tools in pain medicine : Survey of German Pain Society health professional members and members of self-help groups]. / Einstellung zur digitalen Medizin im Schmerzbereich : Eine Umfrage unter Ärzten und Patienten der Deutschen Schmerzgesellschaft und Patientenorganisationen.

Digital medicine has increasing influence on the German healthcare system. In times of social distancing during the ongoing coronavirus disease 2019 (COVID-19) pandemic, digital tools enable health professionals to maintain medical care. Furthermore, digital elements have potential to provide effective guideline-oriented treatment to a broad range of patients independently from location and time. This survey was used to assess the attitudes of members of the German Pain Society (health professionals) and of associated self-help groups (patients) towards digital medicine. It was sent out as an online survey to health professionals in September 2020 and to patients in February 2021. The survey referred especially to present usage, attitude and potential concerns regarding particular digital elements. Furthermore, technical affinity was assessed. In total, 250 health professionals and 154 patients participated in the survey. The results show that-although digital elements are already known-a substantial proportion of health professionals still lack broad transfer to regular treatment. The potential of digital tools seems to be recognized by both groups; interestingly, patients consider digital medicine as more useful than health professionals. Nevertheless, concerns about for example data security or digital competence remain in both groups. Taken together, our results indicate that disruptive changes, as the implementation of digital medicine in the healthcare system, have to be guided by intense education and channeled by political policies in order to successfully integrate digital elements into medicine on a long-term basis. This would be in favor for all involved parties and is demanded especially by patients.

Combining Deep Eutectic Solvents with TEMPO-based Polymer Electrodes: Influence of Molar Ratio on Electrode Performance.

For sustainable energy storage, all-organic batteries based on redox-active polymers promise to become an alternative to lithium ion batteries. Yet, polymers contribute to the goal of an all-organic cell as electrodes or as solid electrolytes. Here, we replace the electrolyte with a deep eutectic solvent (DES) composed of sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) and N-methylacetamide (NMA), while using poly(2,2,6,6-tetramethylpiperidin-1-yl-oxyl methacrylate) (PTMA) as cathode. The successful combination of a DES with a polymer electrode is reported here for the first time. The electrochemical stability of PTMA electrodes in the DES at the eutectic molar ratio of 1 : 6 is comparable to conventional battery electrolytes. More viscous electrolytes with higher salt concentration can hinder cycling at high rates. Lower salt concentration leads to decreasing capacities and faster decomposition. The eutectic mixture of 1 : 6 is best suited uniting high stability and moderate viscosity.

Reconstruction of the anatomy of the hip in total hip arthroplasty with two different kinds of stems.

BACKGROUND: The reconstruction of the individual anatomy is important in total hip replacement. The aim of the study was to compare two different kinds of stems with respect to the reconstruction of the individual anatomy of the hip. METHODS: We compared the restoration of the anatomical parameters (horizontal and vertical offset, femoral neck-shaft angle (NSA) and leg length) of 100 unilateral CoreHip (CH) implantations with 100 unilateral implantations of a standard anatomical stem (Exception (E)). The CoreHip has three different NSAs and exhibits a constant femoral neck length for the different sizes. The Exception stem has a standard and lateralized version with two different NSAs and, in both versions, the femoral neck length increases proportionately with size. The anatomical parameters of the operated and healthy sides were measured and the differences between the two stems compared. RESULTS: The horizontal (2.5 ± 2.8 mm (mean ± SD) for CH vs. 5.4 ± 4.1 mm for E, p < 0.001) and vertical offset (4.1 ± 3.5 mm for CH vs. 5.0 ± 3.8 mm, p = 0.024) and femoral neck-shaft-angle (1.7 ± 1.6 degrees for CH vs. 5.6 ± 3.4 degrees for E, p < 0.001) could be reconstructed significantly better with the CoreHip system. There was a tendency for the leg length (4.0 ± 3.9 mm for CH vs. 4.5 ± 3.8 mm; p = 0.11) to be better restored with the CoreHip. CONCLUSION: The reconstruction of the individual anatomy of the hip with an endoprosthesis could be realized significantly better with the stem that was designed with three different femoral neck-shaft angles and a constant femoral neck length over different sizes.

All-Conjugated Polymer Core-Shell and Core-Shell-Shell Particles with Tunable Emission Profiles and White Light Emission.

Future applications of conjugated polymer particles (CPP) in medicine, organic photonics, and optoelectronics greatly depend on high performance and precisely adjustable optical properties of the particles. To meet these criteria, current particle systems often combine conjugated polymers with inorganic particles in core-shell geometries, extending the possible optical characteristics of CPP. However, current conjugated polymer particles are restricted to a single polymer phase composed of a distinct polymer or a polymer blend. Here, a synthetic toolbox is presented that enables the synthesis of monodisperse core-shell and core-shell-shell particles, which consist entirely of conjugated polymers but of different types in the core and the shells. Seeded and fed-batch dispersion polymerizations based on Suzuki-Miyaura-type cross-coupling are investigated. The different approaches allow accurate control over the created interface between the conjugated polymer phases and thus also over the energy transfer phenomena between them. This approach opens up completely new synthetic freedom for fine tuning of the optical properties of CPP, enabling, for example, the synthesis of individual white light-emitting particles.

Biodegradable Polyimidazole Particles as Contrast Agents Produced by Direct Arylation Polymerization.

Conjugated polymer particles provide an important platform for the development of theranostic nanoagents. However, the number of biocompatible and foremost biodegradable π-conjugated polymers is limited. Imidazole is a π-conjugated motif that is abundant in biological systems. Oxidative degradation of imidazole is present in nature via enzymatic or free radical processes. In this work, we introduce polymer particles consisting purely of polyimidazole. We employ direct arylation polymerization and adapt it to a dispersion polymerization protocol to yield uniform and narrowly dispersed nanoparticles. We employ this mechanism to produce linear and cross-linked polymer particles to tune the optical properties from fluorescent to photoacoustically active. We show that the particles can be degraded by H2O2 as well as by reactive oxygen species produced by cells and we detect the degradation products. Altogether, our results suggest that polyimidazole particles represent ideal candidates for theranostic applications.

A highly specific and sensitive serological assay detects SARS-CoV-2 antibody levels in COVID-19 patients that correlate with neutralization.

OBJECTIVE: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic challenges national health systems and the global economy. Monitoring of infection rates and seroprevalence can guide public health measures to combat the pandemic. This depends on reliable tests on active and former infections. Here, we set out to develop and validate a specific and sensitive enzyme linked immunosorbent assay (ELISA) for detection of anti-SARS-CoV-2 antibody levels. METHODS: In our ELISA, we used SARS-CoV-2 receptor-binding domain (RBD) and a stabilized version of the spike (S) ectodomain as antigens. We assessed sera from patients infected with seasonal coronaviruses, SARS-CoV-2 and controls. We determined and monitored IgM-, IgA- and IgG-antibody responses towards these antigens. In addition, for a panel of 22 sera, virus neutralization and ELISA parameters were measured and correlated. RESULTS: The RBD-based ELISA detected SARS-CoV-2-directed antibodies, did not cross-react with seasonal coronavirus antibodies and correlated with virus neutralization (R2 = 0.89). Seroconversion started at 5 days after symptom onset and led to robust antibody levels at 10 days after symptom onset. We demonstrate high specificity (99.3%; N = 1000) and sensitivity (92% for IgA, 96% for IgG and 98% for IgM; > 10 days after PCR-proven infection; N = 53) in serum. CONCLUSIONS: With the described RBD-based ELISA protocol, we provide a reliable test for seroepidemiological surveys. Due to high specificity and strong correlation with virus neutralization, the RBD ELISA holds great potential to become a preferred tool to assess thresholds of protective immunity after infection and vaccination.

Editorial Commentary: High Tibial Osteotomy Is Effective, Even in Patients With Severe Osteoarthritis: Contradiction of Another Dogma From the Past.

High tibial osteotomy is a widespread treatment option and has been performed in the treatment of osteoarthritis long before joint replacements started their triumphant era in the last third of the last century. However, osteotomies have again gained increased interest and popularity within the last 2 decades. Historically, osteotomies have mainly been recommended for early osteoarthritis and contraindicated for advanced osteoarthritis. However, over time, some historic but widespread dogmas have already been contradicted regarding high tibial osteotomy. Osteotomies are very well possible and can yield excellent outcomes, even in patients with severe osteoarthritis. Thus, another dogma from the past is contradicted.

Prior high tibial osteotomy is not a contraindication for medial unicompartmental knee arthroplasty.

PURPOSE: To report on the outcome and complications of minimal invasive medial unicondylar knee arthroplasty (UKA) after failed prior high tibial osteotomy (HTO) as treatment for medial osteoarthritis in the knee. The hypothesis was that good results can be achieved, if no excessive postoperative valgus alignment and abnormal proximal tibial geometry is present. METHODS: All medial UKAs after failed prior HTO (n = 30), performed between 2010 and 2018 were retrospectively reviewed. The patients were followed for revision surgery and survival of the UKA (defined as revision to TKA). Clinical examination using the Knee Society Score (KSS), Oxford Knee Score (OKS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), as well as radiological examination was performed. Radiographs were studied and the influence of the demographic factors and the radiographic measurements on the survival and the clinical outcome was analysed. RESULTS: After a follow-up of 4.3 ± 2.6 years (2.1-9.9) 27 UKAs were available. The survival rate was 93.0%. Two UKAs were revised to TKA (excessive valgus alignment and tibial loosening with femoropatellar degeneration). Two further patients had revision surgery (hematoma and lateral meniscus tear). Follow-up clinical and radiological examination was performed in 21 cases: KSS 82.9 ± 10.1 (54.0-100.0), KSS (function) 93.3 ± 9.7 (70.0-100.0); OKS 42.7 ± 6.0 (25.0-48.0); WOMAC 7.9 ± 15.6 (0.0-67.1). No significant influence of demographic factors or radiological measurements on the clinical outcome was present. CONCLUSION: Prior HTO is not a contraindication for medial UKA, because good-to-excellent results can be achieved in selected patients with medial osteoarthritis and previous HTO, treated with medial UKA, in a midterm follow-up. Excessive mechanical valgus axis should be avoided; therefore, patient selection and accurate evaluation of medial laxity, preoperative mechanical axis, joint line convergence and proximal tibial geometry are important. LEVEL OF EVIDENCE: III.

Biomechanical evaluation of three patellar fixation techniques for MPFL reconstruction: Load to failure did not differ but interference screw stabilization was stiffer than suture anchor and suture-knot fixation.

PURPOSE: The purpose of this study was to compare the maximum load to failure and stiffness of three medial patella-femoral ligament (MPFL) reconstruction techniques: (i) suture anchor fixation (SA), (ii) interference screw fixation (SF), and (iii) suture knot (SK) patellar fixation. The null hypothesis was that the comparison between these three different patella fixation techniques would show no difference in the ultimate failure load and stiffness. METHODS: Reconstruction of the MPFL with gracilis tendon autograft was performed in 12 pairs of fresh-frozen cadaveric knees (24 knees total; mean age, 63.6 [Formula: see text] 8.0 years). The specimens were randomly distributed into 3 groups of 8 specimens; SA reconstruction was completed with two 3.0-mm metal suture anchors; (SF) fixation was accomplished by two 6-mm bio-composite interference screws; SK fixation at the lateral side of the patella was accomplished after drilling two semi-patellar tunnels with a diameter of 4.5 mm. The reconstructions were subjected to cyclic loading for 10 cycles to 30 N and tested to failure at a constant displacement rate of 15 mm/min using a materials-testing machine (MTS 810 Universal Testing System). The final load of failure (N), stiffness (N / mm) and failure mode was recorded in each specimen and followed by statistical analysis. RESULTS: There was no significant difference in mean ultimate failure load among the three groups. The SK group failed at a mean ([Formula: see text] SD) ultimate load of 253.5 [Formula: see text] 38.2 N, the SA group failed at 243 [Formula: see text] 41.9 N and the SF group at 263.2 [Formula: see text] 9.06 N. The SF group had a mean stiffness of 37.8 [Formula: see text] 5.7 N/mm. This was significantly higher (p < 0.05) than the mean stiffness value achieved for the SK group 21.4 [Formula: see text] 9.5 N/mm and the SA group 18.7 [Formula: see text] 3.4 N/mm. The most common mode of failure in the SA group was anchor pullout, and in the SK group was failure at the graft-suture interface. All the reconstructions in the SF group failed due to tendon graft slippage from the tunnel. CONCLUSION: Load to failure was not significantly different between the 3 techniques. However, screw fixation was found to be significantly stronger than the anchor and the suture knot fixation in terms of rigidity of the reconstruction. From a clinical point of view, all methods of fixation can be used reliably for MPFL reconstruction, since they were found to be stronger than the native MPFL.

Injury Incidence Rates and Profiles in Elite Taekwondo during Competition and Training.

This study aimed to investigate exposure adjusted injury incidence rates and profiles associated with training and competition in an elite taekwondo athlete population. 82 athletes were investigated for injuries over a period of 5 years. Individual fight time exposure for training and competition was recorded. The type and location of the injuries were classified and exposure-adjusted injury incidence rates (IIR) were calculated per 1000 h for training and competition. 66 athletes with a mean age of 19.3±4.2 years and 172 injuries were included in the final data assessment. The exposure adjusted IIR was significantly higher during competition (p<0.001) with a rate ratio of 6.33 (95% CI 4.58-8.69). Ankle and foot region as well as hand and wrist were most affected with significant higher IIR in competition (p<0.001). Joint injuries, fractures, and bruising occurred the most. Fractures occurred mainly to the hand and wrist region. Future investigations should focus on exposure adjusted injury data including analyses of the detailed mechanism leading to especially severe injuries to improve specific injury prevention in competition and promote evolution of protective gear.

Soaking of autografts in vancomycin is highly effective in preventing postoperative septic arthritis after revision anterior cruciate ligament reconstruction.

PURPOSE: To determine and compare the incidence of postoperative septic arthritis following revision anterior cruciate ligament reconstruction (R-ACLR) with and without soaking of the graft in vancomycin solution prior to implantation in a large single-centre series. METHODS: A total of 2155 isolated R-ACLR with autologous tendons were performed from 2004 to 2019 and were reviewed with regard to the occurrence of postoperative septic arthritis. From February 2017 onwards, all grafts were wrapped in a vancomycin-soaked (5 mg/ml) gauze swab between harvest and implantation (517 patients, treatment group (2), prospectively followed). These were compared to 1638 patients before that date (control group (1), retrospectively evaluated). The technique of R-ACLR did not significantly change during the years of the study. Hamstring tendons were used in 1310 patients (60.8%) and quadriceps tendons with patellar bone block were used in 845 patients (39.2%), respectively, with no difference between the groups (n.s.). Routine follow-up examination was performed 6 weeks postoperatively (follow-up rate 96.5%), and patients with no treatment for septic arthritis until that time were classified as non-infected. RESULTS: There were 14 cases of postoperative septic arthritis in group 1 (incidence 0.9%), and none in group 2 (incidence 0.0%), respectively. The difference was significant (p = 0.029). CONCLUSION: Soaking of the graft in vancomycin solution prior to implantation dramatically reduces the incidence of postoperative septic arthritis in R-ACLR. LEVEL OF EVIDENCE: III.

Posterior cruciate ligament lesions are mainly present as combined lesions even in sports injuries.

PURPOSE: To analyse 1000 consecutive patients, treated with isolated or combined posterior cruciate ligament (PCL) reconstruction in a single centre according to the epidemiological factors and differences in injury patterns depending on the activity during trauma. METHODS: Between 2004 and 2019, one thousand isolated and combined PCL reconstructions were performed. The medical charts and surgical reports of all patients were analysed regarding epidemiological factors. The PCL lesions were divided into isolated and combined lesions with at least one additional ligamentous injury. The influence of activity during accident and additional injury on the presence of isolated or combined lesions and injury patterns was calculated. RESULTS: In 388 patients (38.8%), sporting activity was the main activity in PCL lesions, followed by traffic accidents in 350 patients (35.0%). Combined injuries were present in 227 patients (58.5%) with sports injuries and 251 patients (71.7%) with traffic accidents. Only during handball, an isolated PCL lesion (69.1%) was more common than a combined lesion. Highest rate of combined lesions was present in car accidents (91.7%). In all activities except skiing and biking, the most common additional peripheral injury was a tear of the posterolateral corner. In skiing and biking accidents, the most common additional peripheral lesion was a lesion of the medial collateral ligament. In patients with PCL lesion and additional fracture of the same lower extremity, a combined lesion was more common than an isolated lesion (p = 0.001). CONCLUSION: Combined PCL lesions are more common than isolated lesions, even in sports injuries (except handball). Incidence and injury pattern vary depending on activity during trauma. Main additional peripheral lesion is a lesion of the posterolateral corner, except biking and skiing accidents where a medial lesion is more common. LEVEL OF EVIDENCE: Level III.

Soaking of the graft in vancomycin dramatically reduces the incidence of postoperative septic arthritis after anterior cruciate ligament reconstruction.

PURPOSE: To determine and compare the incidence of postoperative septic arthritis following anterior cruciate ligament reconstruction (ACLR) with and without soaking of the graft in vancomycin solution prior to implantation in a large single-centre case series. METHODS: From 2004 to 2019, a total of 10,516 primary ACLR were performed and reviewed with regard to the occurrence of postoperative septic arthritis. From February 2017 onwards, all grafts were wrapped in a vancomycin-soaked (5 mg/ml) gauze swab between harvest and implantation (2294 patients, treatment group (2), prospectively followed). These were compared to 8222 patients before that date (control group (1), retrospectively evaluated). The technique of ACLR did not significantly change during the years of the study. There was no difference between the groups with regard to graft choice: Hamstring tendons were used in 99% and quadriceps tendons were used in 1% in both groups, respectively (n.s.). Routine follow-up examination was performed at 6 weeks (follow-up rate 97.1%) postoperatively. Patients with no treatment for septic arthritis at that time were classified as non-infected. RESULTS: There were 35 cases of postoperative septic arthritis in group 1 (incidence: 0.4%), and none in group 2 (incidence 0.0%), respectively. The difference was significant (p < 0.001). CONCLUSIONS: Soaking of the graft in vancomycin solution prior to implantation dramatically reduces the incidence of postoperative septic arthritis in primary ACLR and should, therefore, be used in prevention of this major complication. LEVEL OF EVIDENCE: III.

Lower incidence of post-operative septic arthritis following revision anterior cruciate ligament reconstruction with quadriceps tendon compared to hamstring tendons.

PURPOSE: To determine and compare the incidence of post-operative septic arthritis following revision anterior cruciate ligament reconstruction (R-ACLR) with autologous quadriceps tendon (with patellar bone block) compared to autologous hamstring tendons (semitendinosus and gracilis). METHODS: A total of 1638 isolated R-ACLR with either autologous hamstring tendons (n = 1004, 61.3%) or quadriceps tendon (n = 634; 38.7%) were performed between 2004 and 2017 and were retrospectively analysed with regard to the occurrence of post-operative septic arthritis. The technique of R-ACLR did not significantly change during the years of the study. All patients received pre-op i.v.antibiotics, but no presoaking of the grafts in vancomycin was performed in the years of the study. The individual decision of graft choice was based on graft availability, tunnel position and the presence of tunnel widening. Generally, hamstring tendons were preferred. There were no clinically relevant differences between the groups regarding gender or age. Routine follow-up examination was performed 6 weeks after the index operation (follow-up rate 96.5%), and patients unsuspicious for septic arthritis at that time were classified as non-infected. RESULTS: Fourteen patients with septic arthritis were identified, resulting in an overall incidence of 0.85%. There was one patient with septic arthritis in the quadriceps tendon group (incidence: 0.16%) and 13 patients in the hamstring tendons group (incidence: 1.29%), respectively. The difference was significant (p = 0.013). CONCLUSION: In this series, the incidence of post-operative septic arthritis after R-ACLR was lower when quadriceps tendon graft was used compared to hamstring tendon grafts. LEVEL OF EVIDENCE: III.

Excellent long-term results in combined high tibial osteotomy, anterior cruciate ligament reconstruction and chondral resurfacing in patients with severe osteoarthritis and varus alignment.

PURPOSE: To determine survivorship and functional results of medial open-wedge high tibial osteotomy (HTO) combined with anterior cruciate ligament reconstruction (ACLR) and a chondral resurfacing (CR) procedure (abrasion/microfracture) in patients with Kellgren-Lawrence grade 3 and 4 osteoarthritis with full thickness-cartilage defects, ACL-insufficiency and varus alignment. METHODS: A cohort of 23 patients undergoing a combined procedure of HTO (fixation with angular stable internal fixator, Tomofix®), ACLR and CR for the treatment of severe symptomatic medial osteoarthritis, ACL insufficiency and varus alignment (> 4°) between 2005 and 2009 was prospectively surveyed with a minimum follow-up of 10 years with regard to survival (not requiring arthroplasty), functional outcome (subjective IKDC score), pain level (numeric rating scale), Oxford Knee Score (OKS) and subjective satisfaction. The Wilcoxon signed-rank-test was used for statistical evaluation of non-parametric data in these related samples. RESULTS: Twenty-one cases were included, one case with incomplete follow-up data and another case excluded. The follow-up rate was 91% at 12.0 ± 1.0 years (10.0-13.4). Mean age at time of surgery was 47.3 ± 5.9 years (37.8-57.7). At final follow-up, no arthroplasty was performed in any of the cases (survival: 100%). Subjective IKDC score improved from 47 ± 11 to 75 ± 15 at 1, 72 ± 15 at 3, 73 ± 17 at 6 years and 70 ± 16 at final follow-up (p < 0.001), respectively. At final follow-up the OKS was 40 ± 7 (17-48) and pain-level significantly decreased from 7.5 ± 1.0 preoperatively to 2.9 ± 2.3 (p < 0.001) at final follow-up. All patients were satisfied with the result and stated that they would retrospectively undergo the procedure again. CONCLUSION: A combined approach of HTO, ACLR and a CR shows excellent results in a long-term follow-up in selected young patients even in severe osteoarthritis. However, the role and potential benefit of the ACLR and CR compared to HTO alone remains unclear. LEVEL OF EVIDENCE: Therapeutic case series, Level IV.