Surgery of the Distal Limb

Effects of two different topographic approaches for combined sciatic and femoral nerve block in calves, guided by ultrasound and neurostimulation

To evaluate the sensory and motor effects promoted by a combined sciatic and femoral nerve block in calves using two approaches. Six calves were used, in a crossover study. Ultrasound combined with neurostimulation, was used to perform the following block combinations: the proximal approach (PA), which consisted of the association of the parasacral approach (sciatic nerve block) and ventral to the ilium approach (femoral nerve block); distal approach (DA) consisted of the association of a lateral approach to the pelvic limb approach (sciatic nerve block), and an inguinal approach, underneath the femoral trigone (femoral nerve block). Pressure algometry and motor function of the limb where evaluated. Mechanical nociceptive threshold (MNT) increase, and ataxia duration means were 9.5 ± 0.7 kg and 10.4 ± 3.9 hr for PA and 10.4 ± 3.9 kg and 12.7 ± 1.9 hr for DA, respectively with no significant difference. There was no significant difference between MNT elevation time and the duration of ataxia using the same approach. The DA treatment showed significant MNT elevation in 72% of the tested regions, while the PA treatment showed an elevation in 100% regions tested. Topographic approaches closer to where the spinal nerves emerge produced a larger desensitised area.

Septic Tenosynovitis of the Digital Flexor Tendon Sheath in 83 Cattle

Septic tenosynovitis of the digital flexor tendon sheath (DFTS) is the second most prevalent infection of deeper structures of the distal limb in cattle, after septic arthritis of the distal interphalangeal (DIP) joint. Depending on the type of infection and the involvement of adjacent anatomical structures, various surgical techniques may be used for therapy: Incising the DFTS to resect one or both digital flexor tendons (RDFT), additional resection of the DIP joint (RDIP) or additional digital amputation (RAMP). Our goal was to describe clinical findings and outcome in cattle patients (euthanasia vs. treatment) and the success of surgical methods including improvement of locomotion and postoperative survival time (POST). Data of eighty-three cattle with a mean age of 4.3 years were reviewed in this retrospective study. Overall, 57.7% of tenosynovitis cases were in the lateral DFTS of a hind limb. Fifty-five cattle were treated surgically; the remaining 28 cattle were euthanized following diagnosis. The median cumulative POST was 17.3, 83.1, and 11.9 months for RDFT, RDIP, and RAMP, respectively. Fatal postoperative complications occurred in three cattle. We conclude that the applied methods were successful and allowed the animals to almost reach the average life expectancy of an Austrian dairy cow.

Objective assessment of lameness in cattle after foot surgery

Assessment of lameness in cattle after foot surgery is important to monitor the recovery period, to improve the long-term success and the cows` welfare. This longitudinal multicenter retrospective study was carried out to evaluate the usefulness of automated tools of weight bearing and gait analysis following foot surgery to support the clinician to monitor lameness in cattle. For this purpose, the effect of involvement of different anatomical structures and the use of different surgery methods on gait parameters of post-operative recovery was assessed. The study consisted of 2 experiments and included cattle with unilateral foot pathologies located in the digital region which needed 1 (experiment 1; n = 30) or 2 (experiment 2; n = 4) surgical interventions. The surgical techniques were debridement, joint lavage, partial resection of bones, tendons or synovial structures, total resection of the sesamoid bone and digit amputation. Two accelerometers (400 Hz; kinematic outcome = stance phase duration; kinetic outcome = foot load and toe-off), a 4-scale weighing platform (difference of mean weight distribution across the limbs; Δ_weight) and a subjective locomotion score were used to evaluate gait parameters every 3 to 4 days after surgery. A repeated measures ANOVA was used in experiment 1 and a receiver operator characteristic analysis was used to determine the optimal cutoff values in experiment 2. Results showed that the differences across limbs for the pedogram variables of stance phases and peaks of foot load and toe-off, Δ_weight and the locomotion score were highest if joints or sesamoid bones were involved, suggesting that these cattle were more severely lame compared to cattle with more superficial foot pathologies. There was a significantly lower degree of lameness after surgical debridement and after digit amputation compared to partial and total resection of anatomical structures of the foot. The use of accelerometers and a 4-scale weighing platform represent promising objective tools for post-operative monitoring of lameness and can support the clinician in gait assessment to improve the long-term success of surgical interventions in the area of the foot.

Pathogenesis and Treatment of Toe Lesions in Cattle Including "Nonhealing" Toe Lesions

Toe lesions in cattle include apical white line disease, thin soles, toe ulcers, toe necrosis, digital dermatitis-associated toe ulcers/toe necrosis, and fracture of the claw capsule and the apex of the distal phalanx. For anatomic reasons, the early stages of toe abnormalities (thin sole, apical white line disease, toe ulcer) are at risk of developing into a bone infection. The prevalence of toe lesions differs in dairy herds and feedlots: it is low at the animal level in feedlots and dairies; however, the herd prevalence of toe lesions can reach 50% in dairy herds with endemic digital dermatitis infection.