A surgical access system comprises a wound retractor comprising an outer anchor, an inner anchor, and a flexible, tubular sheath extending therebetween. Embodiments of the outer anchor comprise an outer ring rotatable around an annular axis thereof, thereby rolling the sheath therearound when retracting an incision or opening in a body wall. The sheath comprises a plurality of fibers or strands that improve the abrasion and puncture resistance thereof. Consequently, the surgical access system is useful in procedures in which damage to the sheath is likely, for example, orthopedic hip replacement, and spinal procedures. In some embodiments, the sheath tapers from the outer ring to the inner ring.