Proximal suspensory desmitis of the hindlimb was diagnosed using local analgesic techniques and ultrasonography in 42 horses. Subtarsal analgesia resulted in substantial improvement in lameness in 36 of 41 horses in which local analgesic techniques were used. In the remaining five horses lameness was improved by perineural analgesia of the tibial nerve (three) or the tibial and fibular nerves. Intra-articular analgesia of the tarso-metatarsal joint produced a similar degree of improvement in two of 24 horses in which lameness had been improved by subtarsal analgesia. Ultrasonographic abnormalities of the proximal one third of the suspensory ligament of the lame limb only were detected in 36 of the 37 unilaterally lame horses. Abnormalities were detected in both suspensory ligaments in the five bilaterally lame horses and in one horse with unilateral lameness. Radiographic abnormalities of the proximal aspect of the third metatarsal bone of the lame or lamer limb were detected in 23 horses. Four horses have been in full work for more than 1 year without recurrent lameness. Two other horses resumed full work but had lameness due to another cause. Six horses are in light work despite mild lameness. Sixteen horses have been retired or humanely destroyed due to persistent or recurrent lameness.