Neuromuscular control in patients with acute ACL injury during stair ascent – A pilot study

Neuromuscular Control During Stair Descent and Artificial Tibial Translation After Acute ACL Rupture

“… 43 – 45 , 54 To date, only 3 studies have measured ACL deficiency in patients in the acute stage before any rehabilitative intervention. 11 , 16 , 24 Women with an ACL rupture (2-11 months after accident) showed altered neuromuscular activation, and in general a lower quadriceps/hamstring ratio, in the injured leg compared with the uninvolved leg during single- and double-leg squats. 54 In that study, surface electromyographic (EMG) signals were collected, and ratios of average EMG amplitude between injured and uninjured sides, as well as between antagonistic muscles on the same side, were compared without prior normalization.…”

“… 54 A pilot study with male and female participants with an acute ACL deficiency (1-3 weeks after accident) found an activation of only 35% to 50% in the thigh muscles of the injured leg compared with the uninvolved leg (with 100% of activation as reference) during stair ascent. 11 The authors used surface EMG signals during walking on a treadmill at a speed of 5 km/h (1.39 m/s) for submaximal EMG normalization, with stair ascent activity normalized and expressed as a percentage (EMG %) of respective level walking activity. 11 Furthermore, a systematic review reported an increased muscular activity of the hamstrings in patients with acute ACL deficiency during walking, but also a decreased quadriceps activation in the acute stage.…”

“… 11 The authors used surface EMG signals during walking on a treadmill at a speed of 5 km/h (1.39 m/s) for submaximal EMG normalization, with stair ascent activity normalized and expressed as a percentage (EMG %) of respective level walking activity. 11 Furthermore, a systematic review reported an increased muscular activity of the hamstrings in patients with acute ACL deficiency during walking, but also a decreased quadriceps activation in the acute stage. A minority of included studies found prolonged duration of activity in patients with ACL deficiency compared with a control group.…”

“…The objective of this cross-sectional study was to compare neuromuscular activity during (1) stair descent and (2) artificially induced anterior tibial translation while standing in patients with acute ACL rupture compared with a matched healthy control group. Based on the literature, 10 , 11 , 22 , 23 we hypothesized that neuromuscular control would be impaired in participants with acute ACL deficiency, meaning that they would show (1) a reduced quadriceps and enhanced hamstring activation and (2) a decreased and prolonged reflex activity of the hamstrings during artificially induced anterior tibial translation compared with healthy controls.…”

Which assessments are used to analyze neuromuscular control by electromyography after an anterior cruciate ligament injury to determine readiness to return to sports? A systematic review

“…As the non-affected limb may also have deteriorated, the LSI may overestimate the right time for a safe RTS, and therefore, the risk for secondary injury may be higher (23). In acutely injured ACL patients, intra-individual comparison showed bilateral consequences during stair ascent and indicates an alteration in the motor program (‘‘pre-programmed activity’’) (71). In addition, in case of a case-controlled study design, the subjects in the control group should be matched to the ACL participants regarding sex, age, body mass, height, activity level and leg dominance.…”