-Results indicated that canine muscle and periosteum may be sources of MSCs. Periosteum was a superior tissue source for MSC yield and may be useful in allogenic applications.

Equine muscle and periosteum are sources of MSCs. Equine muscle- and periosteal-derived MSCs have osteogenic potential comparable to that of equine adipose- and bone marrow-derived MSCs, which could make them useful for tissue engineering applications in equine medicine.

The compressive, bending and torsional mechanical properties of osteotomized adult equine tibiae stabilized with an interlocking intramedullary nail (nail-tibia composite) were compared with those of intact tibiae to determine the clinical applicability of the the nail for repair of tibial fractures in adult horses. The mean yield load, failure load, and stiffness for the nail-tibia composites were significantly less (P < .05) than those for the intact tibiae in all loading configurations. The mean compressive yield load for the nail-tibia composites was greater than the compressive load calculated from previously reported in vivo data for walking and trotting, and was equal to the load calculated for recovery from anesthesia. The mean yield bending moment for the nail-tibia composites was greater than the bending moment previously calculated for standing, walking, and recovery from anesthesia. The mean torsional yield load for the nail-tibia composites was less than the torsional load determined for the walk from another in vivo study. The design of the interlocking nail evaluated in the present study should be modified to increase torsional and compressive yield strengths and torsional stiffness before reasonable success could be expected for the treatment of adult equine tibial fractures.

Horses with normal locomotor activity appear to have higher load rates for forelimbs compared with hind limbs and higher load rates during the day compared with night. Knowledge of influence of environmental factors and mechanical restraint on limb loading activity may be useful in management of horses with musculoskeletal disorders. This information may also be used for in vitro simulation of in vivo loading of limbs during cyclic biomechanical investigations.