COVID-19 Infection among Elite Football Players: A Nationwide Prospective Cohort Study.

Little is known about the risk of COVID-19 infection among footballers. We aimed to investigate the incidence and characteristics of COVID-19 infection among footballers. In total, 480 football players of Super League Greece and 420 staff members participated in a prospective cohort study, which took place from May 2020 to May 2021. Nasopharyngeal swabs were collected from footballers and staff members weekly. All samples (n = 43,975) collected were tested using the reverse transcriptase polymerase chain reaction (RT-PCR) test for the detection of "SARS-CoV-2". In total, 190 positive cases (130 among professional football players and 60 among staff) were recorded. Out of the 190 cases that turned positive, 64 (34%) cases were considered as symptomatic, and 126 (66%) cases were asymptomatic. The incidence rate of a positive test result for footballers was 0.57% (confidence interval (CI) 0.48−0.68%) and for staff members it was 0.27% (CI 0.20%, 0.34%), respectively. Footballers recorded a twofold increased risk of COVID-19 infection in comparison to staff members (relative risk = 2.16; 95% CI = 1.59−2.93; p-value < 0.001). No significant transmission events were observed during the follow-up period. We found a low incidence of COVID-19 infection among professional footballers over a long follow-up period. Furthermore, the implementation of a weekly diagnostic testing (RT-PCR) was critical to break the transmission chain of COVID-19, especially among asymptomatic football players and staff members.

Recovery Kinetics After Speed-Endurance Training in Male Soccer Players.

PURPOSE: To determine the recovery kinetics of performance, muscle damage, and neuromuscular fatigue following 2 speed-endurance production training (SEPT) protocols in soccer. METHODS: Ten well-trained, male soccer athletes randomly completed 3 trials: work-to-rest ratio (SEPT) 1:5, SEPT/1:8, and a control trial. Training load during SEPT was monitored using global positioning system and heart-rate monitors. Performance (isokinetic strength of knee extensors and flexors, speed, and countermovement jump) and muscle damage (delayed-onset muscle soreness [DOMS] and creatine kinase) were evaluated at baseline and at 0, 24, 48 and 72 h posttraining. Maximal voluntary contraction (fatigue index) of knee extensors and flexors was additionally assessed at 1, 2, and 3 h posttraining. RESULTS: Fatigue increased (P < .05) in SEPT/1:5 (∼4-30%) for 3 h and in SEPT/1:8 (∼8-17%) for 2 h. Strength performance declined (P < .05) in both SEPT trials (∼5-20%) for 48 h. Speed decreased (∼4-18%; P < .05) for 72 h in SEPT/1:5 and for 48 h in SEPT/1:8. Countermovement-jump performance decreased (∼7-12%; P < .05) in both SEPT trials for 24 h. DOMS increased (P < .05) in SEPT/1:5 (∼2-fold) for 72 and in SEPT/1:8 (∼1- to 2-fold) for 48 h. Creatine kinase increased (∼1- to 2-fold, P < .05) in both SEPT trials for 72 h. CONCLUSIONS: SEPT induces short-term neuromuscular fatigue; provokes a prolonged deterioration of strength (48 h), speed (72 h), and jump performance (24 h); and is associated with a prolonged (72-h) rise of DOMS and creatine kinase. Time for recovery is reduced when longer work-to-rest ratios are applied. Fitness status may affect quality of SEPT and recovery kinetics.

Tuberculous pyomyositis: a re-emerging entity of many faces.

Tuberculosis (TB) has become a global concern due to its increasing incidence, particularly in immunocompromised patients, closely following the migratory patterns of populations. TB pyomyositis is a rare extrapulmonary manifestation of TB. Its clinical presentation varies and requires a high degree of suspicion for early diagnosis. We present three patients diagnosed with TB pyomyositis: a 46-year-old man with dermatomyositis (DM) and hepatitis B who presented with fever, muscle weakness, and an abscess at the right proximal arm; a 71-year-old immunocompetent male, with a past medical history of tuberculous lymphadenopathy in childhood, who presented with a 2-month history of fever and pain at the right thigh, and a 44-year-old woman with systemic lupus erythematosus (SLE) on prednisone and methotrexate who presented with skin eruption at her thighs mimicking lupus panniculitis. In all three patients, Mycobacterium tuberculosis was identified as the causative agent. The lack of specific signs, the false negative tuberculin skin test in some cases, and the unfamiliarity of many clinicians with this entity can cause diagnostic delays. Prompt diagnosis requires a high index of suspicion especially in immunocompromised patients with fever.

No difference in osteoarthritis after surgical and non-surgical treatment of ACL-injured knees after 10 years.

PURPOSE: Aim of this study was to record and compare the functional and activity level as well as the manifestations of osteoarthritis after isolated ACL ruptures between patients with conservative treatment and ACL reconstruction with hamstrings tendon graft. METHODS: Thirty-two patients diagnosed with ACL rupture were recorded. Clinical examination included the Tegner and Lysholm activity scale, the International Knee Documentation Committee Subjective Form and KT-1000 arthrometer. Narrowing of the medial and lateral joint spaces was assessed using the IKDC knee examination score. RESULTS: Median follow-up was 10.3 years (range 10-11). Fifteen patients were conservatively treated (median age 33 years, range 25-39). Seventeen patients were operated (median age 31 years, range 20-36). There was significant difference between the mean values of IKDC scores in favour of the ACL-reconstruction group of patients, 86.8 (SD 6.5) versus 77.5 (SD 13.8), respectively (p = 0.04). The mean value of anteroposterior tibial translation was 1.5 mm (SD 0.2) for ACL-reconstruction group of patients, while the corresponding mean value for ACL-conservative group was 4.5 mm (SD 0.5), p = 0.03. Four patients in ACL-reconstruction group had radiological findings of grade C or D according to IKDC form. In ACL-conservative group, five patients presented similar signs (n.s.). CONCLUSIONS: ACL reconstruction using hamstrings autograft resulted in better functional outcome and laxity measurements than ACL-conservative management. However, the incidence of radiological osteoarthritis was similar between the two groups and independent on the pre-operative grade of laxity and functional status of the patients. Equally, bone bruises were not found as a risk factor for the development of osteoarthritis after ACL rupture. LEVEL OF EVIDENCE: Prospective randomized study, Level II.

Neurovascular anatomic relationships to arthroscopic posterior and transseptal portals in different knee positions.

BACKGROUND: No study exists that directly measures the distances between posterior portals and the popliteal artery under arthroscopic conditions. PURPOSE: To define the anatomic relationship between the neural structures and standard posterior arthroscopic portals and between the popliteal artery and posterior as well as transseptal portals in different knee positions. STUDY DESIGN: Descriptive laboratory study. METHODS: Seventeen fresh-frozen cadaveric knees were used. The posterolateral, posteromedial, and transseptal portals were established at 90° of knee flexion. The popliteal artery was revealed using a shaver placed through the posteromedial portal. The distance from those portals to the popliteal artery was measured using a precision caliper. After the measurements were made, each specimen was dissected. The distance from a needle, blade, and cannula in each portal site to the adjacent neural structures was successively measured at 30°, 90°, and 120° of knee flexion. RESULTS: The mean distance (in millimeters) from the posterolateral, posteromedial, and transseptal portals to the popliteal artery was significantly smaller at 30° (32.1 ± 4.6, 36.5 ± 4.9, and 9.0 ± 3.9, respectively) than at 90° (40.7 ± 5.1, 41.0 ± 3.8, and 18.0 ± 3.8, respectively) and 120° (38.4 ± 4.8, 38.7 ± 6.0, and 21.0 ± 4.0, respectively) of knee flexion. The mean distance from the posterolateral portal to the common peroneal nerve at 90° of flexion (needle, 26.6 ± 9.5; blade, 24.7 ± 6.9; cannula, 22.1 ± 6.9) was significantly greater than the distance at 30° (needle, 23.4 ± 6.5; blade, 21.4 ± 6.4; cannula, 18.4 ± 6.3) and 120° (needle, 21.8 ± 6.6; blade, 19.1 ± 6.3; cannula, 17.4 ± 6.7) of knee flexion. The mean distance between the posteromedial portal and the inferior infrapatellar branch of the saphenous nerve at 30° (needle, 18.6 ± 4.3; blade, 15.5 ± 3.3; cannula, 13.7 ± 5.8) of flexion was smaller than at 90° (needle, 20.1 ± 6.1; blade, 16.5 ± 5.3; cannula, 14.3 ± 4.4) and 120° (needle, 21.1 ± 3.6; blade, 17.7 ± 4.9; cannula, 15.1 ± 5.9) of flexion, but there was no statistical significance. The mean distance from the posteromedial portal to the sartorial branch of the saphenous nerve at 30° (needle, 22.8 ± 6.1; blade, 19.8 ± 5.3; cannula, 17.7 ± 6.2) of flexion was significantly smaller than that at 90° (needle, 29.7 ± 3.6; blade, 26.3 ± 6.3; cannula, 23.1 ± 4.7) and 120° (needle, 31.5 ± 3.9; blade, 28.9 ± 4.1; cannula, 25.4 ± 5.1) of flexion. Conclusion/ CLINICAL RELEVANCE: The position of 90° of knee flexion is safe to establish posterior and transseptal arthroscopic portals. The position of 120° of knee flexion is practically safe to establish posteromedial and transseptal portals, but it is unsafe to create a posterolateral portal because the risk of damaging the common peroneal nerve is high. The position of 30° of knee flexion is not recommended to establish posterior arthroscopic portals.

Evaluation of the bone bridge between the bone tunnels after anatomic double-bundle anterior cruciate ligament reconstruction: a multidetector computed tomography study.

BACKGROUND: Double-bundle anterior cruciate ligament (ACL) reconstruction is a technically demanding procedure; it requires drilling 2 tibial and 2 femoral tunnels. Tunnel communication, whether intraoperative or postoperative, is a serious complication: It jeopardizes knee stability and graft function. HYPOTHESIS: During double-bundle ACL reconstruction, special aimers would be helpful to avoid intraoperative bone bridge fracture. The bone bridge between the bone tunnels would maintain its structural integrity, and no tunnel communication would be observed postoperatively because of tunnel widening. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This prospective study included 32 patients undergoing double-bundle ACL reconstruction. A multidetector computed tomography study was performed at a mean of 17 months postoperatively. The thickness of the bone bridge between the bone tunnels was measured in the femoral and tibial sides on an axial and sagittal plane, respectively, at 3 locations: the level of the joint line, the midportion of the bone bridge, and the base of the bone bridge. The bone density of the bone bridge was measured in Hounsfield units in the same locations. Bone density of the anterior tibial cortex and lateral femoral condyle was measured for comparisons. RESULTS: Tunnel communication occurred intraoperatively in 1 patient on the tibial side at the level of the joint line. In the rest of the patients, a well-defined triangular bone bridge was present between the 2 tunnels in the femoral and tibial sides. The thickness at the apex of the bone bridge was 2.0 and 2.2 mm for the femur and tibia, respectively. In addition, the density of the bone bridge at its apex was similar to that of cortical bone. CONCLUSION: This study demonstrated that double-bundle ACL reconstruction, as used with anatomic aimers, produces a low rate of tunnel convergence. The bone bridge remains intact postoperatively, although it is thin at the level of the joint line.

Autograft contamination during preparation for anterior cruciate ligament reconstruction.

BACKGROUND: The autograft preparation process for anterior cruciate ligament reconstruction has a potential for graft contamination. The purpose of this study was to evaluate the possibility of contamination of the bone-patellar tendon-bone and hamstring tendon autograft during preparation for anterior cruciate ligament reconstruction. METHODS: A primary isolated reconstruction of the anterior cruciate ligament with use of bone-patellar tendon-bone autograft (thirty patients) and hamstring tendon autograft (thirty patients) was performed in a prospective, consecutive series of patients. Three tissue samples were obtained for culture from each graft at different time-intervals during the graft preparation. In addition, the erythrocyte sedimentation rate and the C-reactive protein level were evaluated preoperatively and on the third, seventh, and twentieth postoperative days, and the clinical course of all patients was monitored. RESULTS: The time needed for graft preparation was significantly longer for hamstring autografts (nineteen minutes) than for bone-patellar tendon-bone autografts (ten minutes) (p = 0.032). In the hamstring group, cultures of graft tissue from four patients (13%) were positive for bacteria. In the bone-patellar tendon-bone group, cultures of graft tissue from three patients (10%) were positive for bacteria; the difference between groups was not significant (p = 0.923). No patient had development of a postoperative infection. There were no differences between patients with a contaminated graft and those with an uncontaminated graft with regard to postoperative changes in the erythrocyte sedimentation rate or the C-reactive protein level at all time-intervals. CONCLUSIONS: A high rate (12%) of autograft contamination can be expected during autograft preparation for anterior cruciate ligament reconstruction. The contamination rate is almost equal for both bone-patellar tendon-bone and hamstring tendon autografts. We could not identify an association between contaminated grafts implanted in the knee and postoperative inflammatory markers such as the erythrocyte sedimentation rate and the C-reactive protein level.

Patellar tendon length after anterior cruciate ligament reconstruction: a comparative magnetic resonance imaging study between patellar and hamstring tendon autografts.

Patellar tendon shortening after anterior cruciate ligament reconstruction may be associated with anterior knee pain or patellofemoral arthritis. The present study was designed to compare postoperative changes in patellar tendon length after anterior cruciate ligament reconstruction between patellar tendon and hamstring tendon autograft. Magnetic resonance images of both knees (operated and healthy) and functional outcome were documented at least 1 year postoperatively in 16 patellar tendon harvested patients and in 32 hamstrings harvested patients. Patellar tendon length, patella length and Insall-Salvati ratio were measured. The operated knee values were compared to the respective values of the non-operated control knees. A significant 4.2 mm or 9.7% patellar tendon shortening in patellar tendon group and a non-significant 1.14 mm or 2.6% shortening in hamstrings group was detected. No significant difference was detected in terms of major shortening-patella baja-(6% for the patellar tendon group vs. 0% for the hamstring group). There was no significant difference in anterior knee problems between the two groups as evidenced by the Shelbourne score (94 for the patellar tendon group vs. 98 for the hamstring group). Harvesting of the patellar tendon for anterior cruciate ligament reconstruction resulted in a significant shortening of the remaining tendon. In contrast harvesting of the hamstring tendons did not affect significantly the patellar tendon length. However, the incidence of patella baja and overall functional outcome was not significantly different between the two groups.

Localized pigmented villonodular synovitis in the anteromedial compartment of the knee associated with cartilage lesions of the medial femoral condyle: report of a case and review of the literature.

Localized pigmented villonodular synovitis (PVNS) of the knee is an uncommon entity, presenting with different clinical signs and symptoms. We report on a case of a 42-year-old woman who presented with a 3-year history of knee pain and mechanical problems such as locking. On examination she was found to have a palpable and painful mass over the anteromedial joint line. Magnetic resonance imaging (MRI) revealed a soft tissue mass in the anteromedial compartment of the knee joint. The lesion was completely resected arthroscopically, and histologic examination confirmed the diagnosis of localized PVNS. The patient was free of symptoms, and MRI examination showed no evidence of recurrence at 1-year follow-up.