Alteration of Sciatic Nerve Histology and Electrical Function After Compression and After Neurolysis in a Diabetic Rat Model

Abstract

Background Diabetic rats are more sensitive to nerve entrapment. This study was conducted to evaluate nerve function and histological changes in diabetic rats after nerve compression and subsequent decompression. Methods A total of 35 Wistar rats were included. The experimental group was divided into diabetic sciatic nerve compression group (DSNC, n = 5) and diabetic sciatic nerve decompression group (DSND, n = 20). The DSNC model was created by wrapping a silicone tube circumferentially around the nerve for 4 weeks, and then the DSND group accepted nerve decompression and was followed up to 12 weeks. The DSND group was equally divided into DSND 3 weeks (DSND3), 6 weeks (DSND6), 9 weeks (DSND9), and 12 weeks (DSND12) groups. Five rats were taken as normoglycemic control group (CR, n = 5), and another 5 rats as diabetic control group (DM, n = 5). The mechanical hyperalgesia of rats was detected by Semmes-Weinstein nylon monofilaments (SWMs) and by motor nerve conduction velocity (MNCV). These 2 physiological indicators and histology of sciatic nerves were compared among different groups. Results The SWM measurements improved toward normal values after decompression. The SWM value was significantly lower (more normal) in the DSNC groups than in the DSND group (P < 0.05). The MNCV was 53.7 ± 0.8 m/s in the CR group, whereas it was 28.4 ± 1.0 m/s in the DSNC group (P < 0.001). Six weeks after decompression, the MNCV was significantly faster than that in the DSNC group (P < 0.001). Histological examination demonstrated chronic nerve compression, which responded toward normal after decompression, but with degree of myelination never recovering to normal. Conclusions Chronic compression of the diabetic sciatic nerve has measureable negative effects on sciatic nerve motor nerve function, associated with a decline of touch/pressure threshold and degeneration of myelin sheath and axon. Nerve decompression surgery can reverse these effects and partially restore nerve function.

Investigation of Neuropathology after Nerve Release in Chronic Constriction Injury of Rat Sciatic Nerve

“…Double staining of the nerve demonstrated partial remyelination of axons on day 28, which was compatible with the recovery of muscle mass (Figure 2). Similar findings were reported by Hu et al, demonstrating that axon remyelination was observed 6 weeks after nerve decompression in chronic sciatic nerve compression [22].…”

Comment on IWGDF ulcer prevention guidelines

“…Since that review, further evidence has been published/addressing delayed mortality, prolonged survival without recurring ulceration, and improved intra‐operative evoked motor potentials 6,9 . Animal models of induced diabetes with evolving sciatic nerve trunk enlargement and compression demonstrate progressive behavioural, myelination and electrophysiologic changes, but recovery to nearly normal status by 3 months following ND 10 . This animal modelling closely mimics the course and pathologic findings of human DPN.…”

“…6,9 Animal models of induced diabetes with evolving sci- but recovery to nearly normal status by 3 months following ND. 10 This animal modelling closely mimics the course and pathologic findings of human DPN.…”

The effect of gluteus maximus tenotomy in primary total hip arthroplasty with posterior approach: Kinematic analysis of hip extensor strength

“…26 It is known that accompanying diabetes as a concomitant disease in these patients will cause the nerve to be more sensitive due to compression-related edema. 27 In our study, nearly half of the patients in each group were diagnosed with regulated diabetes mellitus.…”