Femoral and obturator neuropathies.

The femoral and obturator nerves both arise from the L2, L3, and L4 spinal nerve roots and descend into the pelvis before emerging in the lower limbs. The femoral nerve's primary function is knee extension and hip flexion, along with some sensory innervation to the leg. The obturator nerve's primary function is thigh adduction and sensory innervation to a small area of the medial thigh.

Using the Mouse Grimace Scale to reevaluate the efficacy of postoperative analgesics in laboratory mice.

Postoperative pain management in animals is complicated greatly by the inability to recognize pain. As a result, the choice of analgesics and their doses has been based on extrapolation from greatly differing pain models or the use of measures with unclear relevance to pain. We recently developed the Mouse Grimace Scale (MGS), a facial-expression-based pain coding system adapted directly from scales used in nonverbal human populations.

The Rat Grimace Scale: a partially automated method for quantifying pain in the laboratory rat via facial expressions.

We recently demonstrated the utility of quantifying spontaneous pain in mice via the blinded coding of facial expressions. As the majority of preclinical pain research is in fact performed in the laboratory rat, we attempted to modify the scale for use in this species. We present herein the Rat Grimace Scale, and show its reliability, accuracy, and ability to quantify the time course of spontaneous pain in the intraplantar complete Freund's adjuvant, intraarticular kaolin-carrageenan, and laparotomy (post-operative pain) assays.