Chemical restraint influences canine hip dysplasia scores for both the standard ventrodorsal hip-extended radiographs and during stress radiography. There is, however, no consensus on the optimal anaesthesia protocol for these stress radiographs. The objective of this study was to evaluate the impact of sedation/anaesthesia on the highest laxity index while using a validated force-measuring device.
Ten Beagle dogs were randomly assigned to undergo stress radiographs under four different sedation/anaesthesia protocols on three separate occasions. Vital parameters, ease of procedure and laxity index were evaluated.Parameters such as temperature, heart rate and respiratory rate remained within normal ranges for all protocols. One dog experienced a seizure after dexmedetomidine and ketamine sedation (protocol C). Protocol B (dexmedetomidine/butorphanol/midazolam) and protocol A (dexmedetomidine/butorphanol) scored significantly better than protocol C (dexmedetomidine/ketamine) and D (dexmedetomidine/propofol) in various aspects of ease of the procedure. While the maximum laxity was similar between protocols A, B and D, only in protocols A and B, a plateau phase was reached. Overall, protocols A and B performed similarly; the best scores were, however, consistently allocated to protocol B.
The sedation protocol dexmedetomidine, butorphanol and midazolam emerged as the most favourable sedation protocol for stress radiography of the coxofemoral joint, offering practicality and a high laxity index, without adverse effects.
