Hamstring-to-quadriceps fatigue ratio offers new and different muscle function information than the conventional non-fatigued ratio.

Commonly used injury risk prediction tests such as the hamstring-to-quadriceps (H:Q) strength ratio appear to be poor predictors of non-contact injury. However, these tests are typically performed in a non-fatigued state, despite accumulated fatigue being an important risk factor for both hamstring strain (HS) and anterior cruciate ligament (ACL) injuries in professional soccer players. After the effect of different H:Q calculation methods were compared and contrasted, the influence of neuromuscular fatigue on the H:Q strength ratio and the association between fatigued and non-fatigued ratio scores were examined. Thirty-five professional soccer players performed a 30-repetition isokinetic fatigue test protocol. Peak knee joint moments were computed for each repetition, and the H:Q conventional ratio (H:QCR ) was calculated using several different, previously published, methods. Knee extensor and flexor moments were statistically decreased by the sixth repetition and continued to decrease until the end of the protocol. However, the H:Q ratio was statistically decreased at the end of the test due to a significant reduction in knee flexor moment (correlation between change in knee flexor moment and change in H:Q, r≈.80; P<.01). Moreover, H:Q measured in fatigue (ie, H:QFatigue ) at the end of the test was greater than H:QCR (1.25-1.38 vs 0.70, P<.01), these variables were weakly correlated (r=.39, P=.02), and subject rankings within the cohort based on H:QCR and H:QFatigue were different (rs =0.25, P=.15). The present data suggest that H:Q ratio measurement during a fatiguing test (H:QFatigue ) provides different outcomes to the traditional H:QCR . The observed significant hamstring fatigue and the difference, and weak correlation, between H:QCR and H:QFatigue indicate that useful information might be obtained with respect to the prediction of HS and ACL injury risk. The potential predictive value of H:QFatigue warrants validation in future prospective trials.

Reversal of excessive oral anticoagulation with a low oral dose of vitamin K1 compared with acenocoumarine discontinuation. A prospective, randomized, open study.

We performed a prospective, randomized, open study in 109 outpatients under chronic anticoagulation with acenocoumarine, presenting with International Normalized Ratios (INRs) > or = 6.0 and no or minor bleeding. All the patients withheld one dose of acenocoumarine; in addition, a treated group also received 1 mg oral vitamin K1. We aimed at a post-intervention INR < 6.0, with a target zone of 2.0-4.0. The INRs were lowered from a mean of 8.1 +/- 1.7 to 4.9 +/- 2.5 in the controls (P = 0.0000) and from 8.4 +/- 2.4 to 3.3 +/- 3 in the treated patients (P = 0.0000). There were no differences in the percentage of patients with post-intervention INRs < 6.0 or within the therapeutic zone. One-third of the treated patients and only 2% of the controls reached INRs < 2.0 (P = 0.0003). Oral vitamin K1 offered no advantage to the simple discontinuation of one dose of acenocoumarine. A substantial number of treated patients were consequently exposed to under-anticoagulation.