What do you think of those special stirrups for sore knees?

The category of stirrups designed to address knee pain has expanded considerably in recent years, and the range of options now available — offset stirrups, wide-track stirrups, flexible stirrups, tilted footbeds, and various combinations of these features — reflects a genuine recognition in the industry that the traditional stirrup design is not optimal for every rider's anatomy. Whether any specific stirrup helps any specific rider depends on the cause of the knee pain and whether the stirrup's design addresses that cause. The most common design modification in knee-friendly stirrups is an offset or angled eye — the part where the stirrup leather attaches is positioned slightly forward of center rather than directly above the footbed. This offset rotates the entire stirrup slightly outward, which encourages the knee and toe to align more naturally for many riders rather than forcing the foot into the inward rotation that traditional stirrups combined with typical leg anatomy can produce. For riders whose knee pain comes from this rotational stress, the offset stirrup can produce genuine relief because it addresses the actual mechanical cause of the problem. Wide-track stirrups distribute the rider's weight across a broader footbed rather than concentrating it at the ball of the foot where a standard stirrup width places it. Flexible stirrups that allow the footbed to move slightly in response to the rider's movement absorb some of the impact forces that rigid stirrups transmit directly through the foot and up the kinetic chain to the knee. The honest assessment is that these stirrups genuinely help some riders and make no meaningful difference for others, and the difference lies almost entirely in whether the stirrup's specific design modification addresses the specific cause of that rider's pain. A rider whose knee pain comes from a structural issue — arthritis, a previous injury, a cartilage problem — may get some reduction in discomfort from a better stirrup but is unlikely to find a stirrup that resolves the underlying condition. Before investing in specialized stirrups it is worth having an experienced instructor evaluate the riding position, because stirrup length and leg position issues cause more rider knee pain than stirrup design does, and those issues are free to correct.