[PDF] Electromyographic analysis of knee exercises in healthy subjects and in patients with knee pathologies. | Semantic Scholar (2024)

The muscle firing patterns in five knee muscles were described and compared during five rehabilitative exercises, which were presumed either to strengthen a specific muscle group or to elicit a cocontraction.

The results indicate that heavy resistance exercises should be included in rehabilitation programs to induce sufficient levels of neuromuscular activation to stimulate muscle growth and strength.

A coor dinated response of quadriceps-hamstrings muscles in the normal knee is demonstrated and may more thoroughly define the coordinated activity of these 2 antagonist muscle groups.

The results provide some information regarding GMed recruitment during exercise, although there were some discrepancies in results between studies which may be due to factors related to EMG measurement and recording as well as the execution of the exercise.

The presence of a quadriceps-hamstrings muscles coordinated response indicates that mechano receptors mediating this reflex arc exist in structures other than the cruciate ligament.

The surface electromyographic activity (EMG) of the VMO relative to the vastus lateralis (VL) during five isometric exercises in eight PFPS female subjects and 19 controls indicated no differences in the V MO:VL proportion between the control group and PFPS participants across the five exercises.

Clinicians should consider applying ice to knee joints prior to exercise for patients following knee surgery with inhibited quadriceps following cryotherapy, as a result of a 38% increase in VM EMG activity during QS and a 30% increased in maximum isometric knee extension strength were found after cryotherapy treatment.

This study suggests that the five closed kinetic chain exercises studied result in minimal A/P shear forces at the knee joint.

Maximum muscle activation of rectus femoris is affected by hip angle, and the findings from this study may be helpful for physical therapists in selecting hip position when instructing patients to do Q-setting exercise.

The results suggest that the VMO may be selectively activated by performing hip adduction exercises, which may be advisable in the treatment of patients with lateral malalignment of the patella with accompanying pain or instability.

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The study demonstrated remarkably different muscle activation levels between the exercises studied and clearly indicates that selection of the exercises needs to be based on the therapeutic objectives.

A hypothesis was formed that suggests the decreased electrical activity at 0 degrees in the effused knees results from reflex inhibition caused by joint capsule distension and intra-articular pressures that change with joint position.

Quad- sets and straight leg-raising exercises in full knee extension offer the best quadriceps rehabilitation pro gram in the patient with a patellar malalignment syn drome and persistent symptoms.

Patellofemoral biomechanics as it relates to quadriceps muscle rehabilitation is reviewed and several modifications that in the clinical experience repeatedly have reduced pain during exercise are summarized.

The results show that motor unit activity depends not only upon joint angle, but also upon peripheral receptor feedback, which is altered in the post-arthrotomy limbs, producing the characteristic "extensor lag" or inability to maintain the knee at 0 degrees while flexing the hip.

The results indicate that muscle pressure is excitatory, but of such low intensity as to be of dubious therapeutic benefit.

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