Electromyography activities in patients with lower lumbar disc herniation

Area of Science:

• Neurology
• Biomedical Engineering
• Orthopedics

Background:

• Lumbar disc herniation (LDH) commonly impairs lower limb muscle function, leading to gait abnormalities.
• Understanding the specific muscle involvement in different LDH levels is crucial for targeted treatment.

Purpose of the Study:

• To evaluate muscle function in patients with L4/L5 and L5/S1 LDH using surface electromyography (SEMG).
• To identify specific muscle groups affected by different levels of lumbar disc herniation.

Main Methods:

• Recruited 20 patients with L4/L5 LDH (L5 Group), 20 with L5/S1 LDH (S1 Group), and 20 healthy controls.
• Recorded SEMG of bilateral tibialis anterior (TA) and lateral gastrocnemius (LG) muscles using a wireless EMG system.
• Analyzed Root-mean-square (RMS), mean power frequency (MPF), and median frequency (MF) to compare muscle activity between symptomatic and asymptomatic limbs.

Main Results:

• Reduced MPF and MF in TA muscles of the L5 Group and LG muscles of the S1 Group compared to controls.
• Symptomatic limbs in the L5 Group showed reduced TA MPF and MF; symptomatic limbs in the S1 Group showed reduced LG MPF and MF.
• Observed alterations in RMS curves, including earlier beta-peaks in TA (L5 Group) and dual peaks in LG (S1 Group) in symptomatic limbs.

Conclusions:

• SEMG effectively identifies muscle dysfunction associated with LDH.
• Tibialis anterior (TA) dysfunction is linked to L4/L5 LDH.
• Lateral gastrocnemius (LG) dysfunction is linked to L5/S1 LDH.