LEWIS C. R. SMITH, BVetMed , TIMOTHY R. C. GREET, BVMS, MVM, CertEO, DESTS, Diplomate ECVS, FRCVS , and ANDREW P. BATHE, MA, VetMB, DEO, Diplomate ECVS Veterinary Surgery August 2009 38 6 681 - 688 Objective—To describe a lateral approach for screw fixation in lag fashion of simple spiral medial condylar fractures of the third metacarpus/metatarsus (MC3/MT3). Study Design—Case series. Animals—Thoroughbred racehorses (n=9). Methods—Nondisplaced medial MC3/MT3 condylar fractures (3 thoracic, 6 pelvic limbs), with mean length 126 mm (range, 91–151 mm) were repaired by internal fixation, under general anesthesia, using multiple 4.5 mm cortical screws inserted in lag fashion from the lateral aspect of the limb, using radiographic or fluoroscopic guidance. Horses were recovered from anesthesia in half-limb casts; 7 unassisted and 2 using a rope-recovery system. Horses had 2 months box rest, 1 month in-hand walking, and follow-up radiographic examination at 3 months. Results—Horses recovered uneventfully from anesthesia. Five horses raced; 1 returned to training, was persistently lame, and was retired to stud; 2 were retired directly to stud; and 1 horse was lost to follow-up. Conclusions—MC3/MT3 medial condylar fractures were successfully repaired by screws inserted n lag fashion form the lateral aspect. Clinical Relevance—Use of a lateral approach to medial condylar MC3/MT3 fractures allows screw insertion perpendicular to the fracture plane without interference with palmar/plantar soft tissue structures or from the splint bones. Although repair was performed under general anesthesia, the technique should be adaptable to application in standing horses.