Background and purposePolymerase chain reaction (PCR) methods enable detection and species identification of many pathogens. We assessed the efficacy of a new PCR and microarray-based platform for detection of bacteria in prosthetic joint infections (PJIs).MethodsThis prospective study involved 61 suspected PJIs in hip and knee prostheses and 20 negative controls. 142 samples were analyzed by Prove-it Bone and Joint assay. The laboratory staff conducting the Prove-it analysis were not aware of the results of microbiological culture and clinical findings. The results of the analysis were compared with diagnosis of PJIs defined according to the Musculoskeletal Infection Society (MSIS) criteria and with the results of microbiological culture.Results38 of 61 suspected PJIs met the definition of PJI according to the MSIS criteria. Of the 38 patients, the PCR detected bacteria in 31 whereas bacterial culture was positive in 28 patients. 15 of the PJI patients were undergoing antimicrobial treatment as the samples for analysis were obtained. When antimicrobial treatment had lasted 4 days or more, PCR detected bacteria in 6 of the 9 patients, but positive cultures were noted in only 2 of the 9 patients. All PCR results for the controls were negative. Of the 61 suspected PJIs, there were false-positive PCR results in 6 cases.InterpretationThe Prove-it assay was helpful in PJI diagnostics during ongoing antimicrobial treatment. Without preceding treatment with antimicrobials, PCR and microarray-based assay did not appear to give any additional information over culture.

Background: A femoral bone tunnel in ACL reconstruction can be constructed from the outside in or from the inside out. When doing it inside out, the approach can be via the anteromedial (AM) portal or through the tibial bone tunnel. It has been suggested that better results might be expected by doing it anteromedially. Clinical results after femoral tunnel drilling via the AM or transtibial (TT) techniques in reconstruction of anterior cruciate ligament (ACL) are presented. Methods: Three hundred patients with ACL injuries were chosen for this study from previously collected data on ACL reconstructions. They were divided into two groups: 150 patients treated with AM drilling and 150 treated with TT drilling. In the AM group, the reconstructions were performed using a semitendinosus graft with the Tape Locking Screw (TLS™) technique (n = 87) or Retrobutton™ femoral and BioScrew™ tibial fixation with a semitendinosus-gracilis graft (n = 63). In the TT group, the fixation method used was Rigidfix™ femoral and Intrafix tibial fixation with a semitendinosus-gracilis graft. The evaluation methods were clinical examination, knee scores (Lysholm, Tegner and IKDC) and instrumented laxity measurements (KT-2000™). Our aim was to evaluate if there was better rotational stability and therefore better clinical results when using AM drilling compared to TT drilling. Results: After excluding revision ACL reconstructions, there were 132 patients in the AM group and 133 in the TT group for evaluation. At the 2-year follow-up, there were 60 patients in the AM group (45.5%) and 58 in the TT group (43.6%). There were no statistically significant differences between the groups in any of the evaluation methods used. Conclusion: Both drilling techniques resulted in improved patient performance and satisfaction. We found no data supporting the hypothesis that the AM drilling technique provides better rotational stability to the knee. Trial registration: ISRCTN registry with study ID ISRCTN16407730. Retrospectively registered Jan 9th 2020.

Background ACL (anterior cruciate ligament) reconstruction remains the gold standard surgical option for patients with ACL tears. There are many fixation devices available for ACL reconstruction. Recent ACL reconstruction strategies are aiming to reproduce the native anatomy and normal kinematics of the knee. This is a five years follow-up report of some of the new devices for graft fixation. A two years follow-up data was published previously. Methods 120 patients were randomized into four different groups (30 each) for ACL reconstruction with hamstring tendons: group I femoral Rigidfix cross-pin and Intrafix tibial extension sheath with a tapered expansion screw; group II Rigidfix femoral and BioScrew interference screw tibial fixation; group III BioScrew femoral and Intrafix tibial fixation; group IV BioScrew fixation into both tunnels. The evaluation methods were clinical examination, knee scores, and instrumented laxity measurements. Results In this 5 years follow-up there were 102/120 (85%) patients available, but only 77 (64,2%) attended the clinical examinations. No significant difference between the groups in the clinical results was detected. Between the 2 and 5 years follow-up there were 6 additional procedures in group I and one in group II. There was a significant difference in additional procedures between group I and the other groups (P = .041). Conclusion There was a statistically significant difference in the additional procedures, most in group I (six). The ACL grafts were intact. Other statistically or clinically significant differences in the 5 years follow-up results were not found. Study design Randomized controlled clinical trial; Level of evidence, 1. Trial registration ISRCTN registry with study ID ISRCTN34011837. Retrospectively registered 17.4.2020.

Background: This is a five years follow-up report of some of the new devices for graft fixation. A two years follow-up data was published previously. As there were no statistically or clinically relevant differences in the results two years postoperatively, we hypothesize that after five years of follow-up there is no difference in the outcome after either cross-pin or absorbable interference screw fixation in ACL (anterior cruciate ligament) reconstruction with hamstring tendon autografts.Methods: 120 patients were randomized into four different groups (30 each) for ACL reconstruction with hamstring tendons: group I femoral Rigidfix cross-pin and Intrafix tibial extension sheath with a tapered expansion screw; group II Rigidfix femoral and BioScrew interference screw tibial fixation; group III BioScrew femoral and Intrafix tibial fixation; group IV BioScrew fixation into both tunnels. The evaluation methods were clinical examination, knee scores, and instrumented laxity measurements. Results: In this 5 years follow-up there were 102/120 (85%) patients available, but only 77 (64,2%) attended the clinical examinations. No significant difference between the groups in the clinical results was detected. There was a significant difference in additional procedures between the 2 and 5 years follow-up, group I had six additional procedures between the 2 and 5 years follow-up (P=.041). Conclusion: There was a statistically significant difference in the additional procedures, most in group I (six). None of these procedures found problems with the ACL graft. Other statistically or clinically significant differences in the 5 years follow-up results were not found. Study design: Randomized controlled clinical trial; Level of evidence, 1.Trial registration: ISRCTN registry with study ID ISRCTN34011837. Retrospectively registered 17.4.2020.