The anterior cruciate ligament (ACL) is a band of dense connective tissue which courses from the femur to the tibia. The ACL is a key structure in the knee joint, as it resists anterior tibial translation and rotational loads. When the knee is extended, the ACL has a mean length of 32 mm and a width of 7-12 mm. There are two components of the ACL, the anteromedial bundle (AMB) and the posterolateral bundle (PLB). They are not isometric with the main change being lengthening of the AMB and shortening of the PLB during flexion. The ACL has a microstructure of collagen bundles of multiple types (mostly type I) and a matrix made of a network of proteins, glycoproteins, elastic systems, and glycosaminoglycans with multiple functional interactions. The complex ultrastructural organization and abundant elastic system of the ACL allow it to withstand multiaxial stresses and varying tensile strains. The ACL is innervated by posterior articular branches of the tibial nerve and is vascularized by branches of the middle genicular artery.

Background: Comprehensive studies evaluating quadriceps tendon (QT) autograft for anterior cruciate ligament (ACL) reconstruction are lacking. The optimal choice of graft between bone–patellar tendon–bone (BPTB), hamstring tendon (HT), and QT is still debatable. Hypothesis: The current literature supports the use of QT as a strong autograft with good outcomes when used in ACL reconstruction. Study Design: Meta-analysis; Level of evidence, 2. Methods: A systematic search of the literature was performed in PubMed, MEDLINE, Cochrane, and Ovid databases to identify published articles on clinical studies relevant to ACL reconstruction with QT autograft and studies comparing QT autograft versus BPTB and HT autografts. The results of the eligible studies were analyzed in terms of instrumented laxity measurements, Lachman test, pivot-shift test, Lysholm score, objective and subjective International Knee Documentation committee (IKDC) scores, donor-site pain, and graft failure. Results: Twenty-seven clinical studies including 2856 patients with ACL reconstruction met the inclusion criteria. Comparison of 581 QT versus 514 BPTB autografts showed no significant differences in terms of instrumented mean side-to-side difference ( P = .45), Lachman test ( P = .76), pivot-shift test grade 0 ( P = .23), pivot-shift test grade 0 or 1 ( P = .85), mean Lysholm score ( P = .1), mean subjective IKDC score ( P = .36), or graft failure ( P = .50). However, outcomes in favor of QT were found in terms of less donor-site pain (risk ratio for QT vs BPTB groups, 0.25; 95% CI, 0.18-0.36; P < .00001). Comparison of 181 QT versus 176 HT autografts showed no significant differences in terms of instrumented mean side-to-side difference ( P = .75), Lachman test ( P = .41), pivot-shift test grade 0 ( P = .53), Lysholm score less than 84 ( P = .53), mean subjective IKDC score ( P = .13), donor-site pain ( P = .40), or graft failure ( P = .46). However, outcomes in favor of QT were found in terms of mean Lysholm score (mean difference between QT and HT groups, 3.81; 95% CI, 0.45-7.17; P = .03). Conclusion: QT autograft had comparable clinical and functional outcomes and graft survival rate compared with BPTB and HT autografts. However, QT autograft showed significantly less harvest site pain compared with BPTB autograft and better functional outcome scores compared with HT autograft.

The use of a QT graft in ACL reconstruction leads to equal or better functional outcomes than does the use of an HT graft, without affecting morbidity.

Dette er siste tekst-versjon av artikkelen, og den kan inneholde ubetydelige forskjeller fra forlagets pdf-versjon. Forlagets pdf-versjon finner du på bjsm.bmj.com: http://dx

Injury to muscles is very common. We have previously observed that basic fibroblast growth factor (b-FGF), insulin growth factor type 1 (IGF-1) and nerve growth factor (NGF) are potent stimulators of the proliferation and fusion of myoblasts in vitro. We therefore injected these growth factors into mice with lacerations of the gastrocnemius muscle. The muscle regeneration was evaluated at one week by histological staining and quantitative histology. Muscle healing was assessed histologically and the contractile properties were measured one month after injury.Our findings showed that b-FGF, IGF and to a less extent NGF enhanced muscle regeneration in vivo compared with control muscle. At one month, muscles treated with IGF-1 and b-FGF showed improved healing and significantly increased fast-twitch and tetanus strengths. Our results suggest that b-FGF and IGF-1 stimulated muscle healing and may have a considerable effect on the treatment of muscle injuries.

The roadmap to elective surgery resumption after this COVID-19 pandemic should be progressive and cautious. The aim of this paper was to give recommendations and guidelines for resuming elective orthopedic surgery in the safest environment possible. Elective surgery should be performed in COVID-free facilities and hospital stay should be as short as possible. For matters of safety, patients considered first for surgery should be carefully selected according to COVID infection status/exposure, age, ASA physical status classification system / risk factors, socioprofessional situation and surgical indication. A strategy for resuming elective surgery in four phases is proposed. Preoperative testing for COVID-19 infection is highly recommended. In any cases, COVID symptoms including fever and increased temperature should be constantly monitored until the day of surgery. Elective surgery should be postponed at the slightest suspicion of a COVID-19 infection. In case of surgery, adapted personal protective equipment in terms of gowns, gloves, masks and eye protection is highly recommended and described.

The present study indicates that some dancing movements could damage the hip joint, which could lead to early osteoarthritis.

Anterior cruciate ligament (ACL) reconstruction has the best chance for success when the graft undergoes extensive biologic remodeling and incorporation after implantation. There are many factors that can lead to graft failure and possible revision surgery. These include patient selection; surgical technique such as graft placement and tensioning; the use of allograft versus autograft; mechanical factors such as secondary restraint laxity; lack of a correct, carefully controlled post-operative rehabilitation program; and biological factors. When a patient presents with knee instability following ligament reconstruction and there is no history of a new trauma or identifiable technical error, biological failure should be considered. However, the biologic response of the grafted tissue is closely linked to the mechanical and biochemical environment into which the graft is placed. Thus, the "biological failure" of the ACL graft is a complex pathological entity whose cause is not fully understood. Failure may be initiated by early extensive graft necrosis, disturbances in revascularization, problems in cell repopulation and proliferation, and as well difficulties in the ligamentization process. However, further study of the biological characterization of a failed graft placed in a correct mechanical environment is warranted.