IshGen 196:8 :ܗ݂ܘܝܘ ܓܝܕܐ ܕܢܒ݁ܥ ܡܢܗ ܟܘܪܗܢܐ ܕܡܬܩܪܐ ܐܢܫܝ‏ : it is the (sciatic) nerve from which arises the illness called sciatica
See the entire entry for ˀnšy n.f. sciatica