Comparison of three methods for arthrodesis of the distal intertarsal and tarsometatarsal joints in horses.
OBJECTIVE
To evaluate the effects of diode laser surgery (LS), surgical drilling (SD), and intraarticular sodium monoiodoacetate (MIA) as methods for fusing the distal intertarsal (DIT) and tarsometatarsal (TMT) joints in horses.


METHODS
Experimental study.


METHODS
Adult horses (15) without radiographic signs of osteoarthritis (OA) of the DIT and TMT joints.


METHODS
Group 1 (n=3) had LS performed bilaterally on DIT and TMT joints; 1 horse was evaluated for 1 week and 2 horses were evaluated for 2 weeks. Group 2 (n=6) had LS on DIT and TMT joints of 1 tarsus and MIA administration into the contralateral DIT and TMT joints and were evaluated for 6 months. Group 3 (n=6) had LS performed on DIT and TMT joints of 1 tarsus and SD of the contralateral DIT and TMT joints and were evaluated for 12 months. Postoperative comfort, lameness, radiography, microradiography, and histology scores were compared using repeated measures ANOVA, and paired or 2 sample t-tests; significance was set at P<.05.


RESULTS
LS caused the least postoperative morbidity. In group 2, horses were less lame in 4 LS-treated limbs and 2 MIA-treated limbs at 6 months when compared with the contralateral limb. In group 3, horses were less lame in 5 LS-treated limbs and 1 SD-treated limb at 6 and 12 months compared with the contralateral limb. On microradiography, 11 MIA joints and 2 LS joints had bone bridging the joint at 6 months whereas 8 SD joints and 5 LS joints had bone bridging at 12 months. Significantly more joint space was bridged by bone in MIA- (51.4%) and SD (46.2%)-treated joints compared with LS joints at 6 (30.6%) and 12 (28.5%) months, respectively (P<.05).


CONCLUSIONS
SD and MIA resulted in more bone bridging of the distal 2 tarsal joints, than LS. However, LS seemingly caused less pain and discomfort to horses in the immediate postoperative period; horses were generally less lame in the LS limb. More laser energy may need to be applied to these joints to promote fusion; however, it may also have beneficial effects beyond fusion. Further research on horses with OA of the distal 2 tarsal joints is needed to determine whether LS can cause soundness without facilitating bony fusion.
Zubrod
Chad J
CJ
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA. zubrod@oakridgevet.com
Schneider
Robert K
RK
Hague
Brent A
BA
Ragle
Claude A
CA
Gavin
Patrick R
PR
Kawcak
Chris E
CE
D000818:Animals; D001174:Arthrodesis / Q000379:methods / Q000662:veterinary*; D005260:Female; D006736:Horses / Q000601:surgery*; D007461:Iodoacetates; D007794:Lameness, Animal / Q000601:surgery; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology / Q000662:veterinary*; D011897:Random Allocation; D013640:Tarsal Joints / Q000601:surgery*; D016896:Treatment Outcome
D007461:Iodoacetates