Introduction: Although neuronal damage has been shown in the motor cortex, cerebellum, and caudoputamen after experimental SAH, gait changes were not evaluated in previous models. We assessed gait changes using an automated CATWALK system.
Methods: Adult wild-type C57BL/6(n=34) mice were randomly assigned to induced sham+vehicle (n=12), SAH+vehicle (n=11) or SAH+PROG (n=11) operation. For SAH induction,60 µL of autologous blood was injected into the cisterna magna. Shams received puncture to the atlanto-occipital membrane. Progesterone (PROG;8mg/kg) was administered at 1hr i.p, and at 6,24,48,72,96,120hr s.c. post-injury. Gait analysis was performed 24hrs before surgery to obtain baseline values followed by postoperative days 2(POD2), 6(POD6) and 9(POD9), with 3 runs for each trial. Swing speed, stride length, and stand time were quantified for each limb (right front(RF), right hind(RH), left front(LF) and left hind(LH)) as dependent variables and reported as percent baseline. Repeated measures ANOVA and one way ANOVA with post-hoc Tukey test were used for analysis.
Results: SAH mice showed reduction in swing speed (the speed of a paw during swing) in all paws compared to shams on POD6 (P<0.05). Stride length (the distance between successive placement of the paw) was decreased in LF foot on POD6 and LH at day POD2 (P<0.05). LH and LF foot showed increased stand times (duration in seconds of contact of a paw with the glass plate) on POD6 and POD9 respectively (P<0.05). Progesterone treatment was not beneficial on any of these parameters.
Conclusions: Following SAH induction with cisternal blood injection, mice show deficits in stride length, stand time and swing speed. This is the first study to evaluate gait impairment in experimental SAH using CATWALK. Further use of this automated and quantitative gait analysis program may help better detect subtle differences between experimental groups in preclinical studies of SAH.
Patient Care: Using neurobehavioral tests such as CATWALK gait analysis system can help study gait changes in experimental SAH animals and allow testing efficacy of therapeutic drugs in gait parameters changed after SAH.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the utility of CATWALK gait analysis system 2) Discuss the gait changes seen after SAH in CATWALK gait analysis system.