Time to recovery of sciatic function index after induced tibialis anterior strain in rats

Muscle strain is a common injury with a high recurrence rate. Due to the heterogeneity of strain injuries, experimental animals provide controlled and reproducible models to investigate such injuries. Sciatic Function Index (SFI) is a clinically feasible method to assess hind limb recovery in rodents after induced injuries.

To investigate time to recovery of SFI after induced-strain in tibialis anterior (TA) muscle in rats.

Sixteen adult male Wister rats were randomly and equally divided to a normal control group that received no intervention, and TA induced muscle strain group. Muscle strain was induced using an external weight that corresponded to 150% of the animal body weight. SFI was tested only once in the control group. For the muscle strain group, SFI was tested on the 1^st, 2^nd, 3^rd, 4^th, 7^th, 11^th, 20^th and 24^th days after strain induction.

Comparisons between group showed significant difference in SFI on the 1^st, 2^nd, 3^rd and 4^th days (p= 0.012, 0.012, 0.012 and 0.028, respectively).

In a rat animal model of TA induced muscle strain, functional recovery measured by SFI is evident on the 7^th day post-injury, which corresponds to the sub-acute phase of injury.

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