For amputee golfers (which term for the purposes of these Modifications includes golfers with limb deficiencies) there are questions over status of prosthetic devices (Rule 14-3) and the application of the prohibition against anchoring the club (Rule 14-1b). The USGA’s position on prosthetic devices is clarified in Decision 14-3/15 and is included here for reference.
14-3/15 Artificial Limbs
An artificial leg or arm is an artificial device within the meaning of the term in Rule 14-3. However, as such a device is used to alleviate a medical condition and the player has a legitimate medical reason to use the device, Exception 1 to Rule 14-3 applies, even if an artificial leg has been modified to aid a player in playing the game or an artificial arm has a fitting specially designed for gripping a golf club. However, the Committee must be satisfied that an artificial limb so modified does not give the player any undue advantage over other players. If the Committee is not satisfied of this, Exception 1 to Rule 14-3 does not apply and use of the device would constitute a breach of Rule 14-3.
Clubs used by a player with an artificial arm must conform with Rule 4-1 except that an attachment may be fitted to the grip or shaft to assist the player to hold the club. However, if the Committee believes that the use of a club modified in this way would give the player an undue advantage over other players, it should deem the attachment an artificial device contrary to Rule 14-3.
Players in doubt about the use of a device should raise the matter as soon as possible with the Committee.
Regarding the application of Rule 14-1b, where a Committee has determined that an amputee golfer is unable to hold and swing his clubs without anchoring because of his limb loss, the golfer is permitted to make a stroke while anchoring the club.
A potential issue for some lower extremity amputee golfers who wear a prosthesis is their inability to climb into or out of bunkers, a situation that probably occurs rather infrequently. On that basis Rule 28 (Ball Unplayable) should apply without need for further modification.