A study sought to determine the impact of diabetic neuropathy (dNP) on the distal versus proximal comparison of weakness in lower and upper limb muscles of patients with type 2 Diabetes Mellitus (T2DM). The results appeared in the Journal of Musculoskeletal & Neuronal Interactions.
The study consisted of 19 healthy male controls without neuropathy (HC), and 35 male T2DM patients, without dNP (n=8), with sensory dNP (n=13) or with sensorimotor dNP (dNPsm; n=14). The researchers measured maximal isometric (IM) and isokinetic (IK) muscle strength and IK muscle endurance of the dominant knee, ankle and elbow, and maximal IM handgrip strength using dynamometry.
The results showed that ankle muscle endurance was lower compared to the knee, independently of dNP (p<0.001). Maximal IK ankle muscle strength was also lower compared to the knee, albeit only in dNPsm (p=0.003), the researchers noted. They found no differences between maximal IM handgrip and elbow strength.
“Our results suggest an impact of T2DM -with or without dNP- on lower limb muscle strength more distally than proximally, while this was not observed in the upper limb. The gradient of dNP seemed to be a determining factor for the maximal muscle strength, and not for muscle endurance, in the lower limb,” the researchers concluded.
Keywords: Diabetic Neuropathy, Distal Versus Proximal Comparison, Lower and Upper Limb, Muscle Strength, Type 2 Diabetes Mellitus