Surgical management of digit disorders in cattle

Modified abaxial approach for resection of the distal sesamoid bone and distal interphalangeal joint while preserving the digital flexor tendons of three Angus bulls with septic arthritis

CASE DESCRIPTION 3 Angus bulls, aged 2 to 3 years, with severe lameness of 2 to 4 weeks' duration and swelling proximal to the coronary band of the affected limb were evaluated after failing to respond to antimicrobial treatment. CLINICAL FINDINGS Septic arthritis of a distal interphalangeal joint (DIPJ) was diagnosed in all 3 bulls on the basis of results of a physical examination, radiographic and ultrasonographic evaluations of the affected foot, and cytologic evaluation of synovial fluid from the affected DIPJ. TREATMENT AND OUTCOME A novel modified abaxial approach was used to resect the infected distal sesamoid bone (navicular bone) and DIPJ of all 3 bulls. A window was created in the abaxial hoof wall that was lateral to and of sufficient size to extract the navicular bone. Following removal of the navicular bone, the DIPJ was debrided and resected and an orthopedic block was applied to the contralateral claw to minimize weight bearing on the infected digit. Two bulls also had a fiberglass cast applied to the affected limb to help immobilize the DIPJ. All 3 bulls recovered without complications, and 2 bulls were no longer lame, whereas the remaining bull was only mildly lame, at 4 to 5 weeks after surgery. CLINICAL RELEVANCE The modified abaxial approach described for surgical resection of the DIPJ allowed extraction of the infected navicular bone without damage to the digital flexor tendons, something that cannot be achieved with other abaxial approaches. This approach is best used for patients without septic tenosynovitis.

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.

Arthrodesis of the proximal interphalangeal joints of a hindlimb in a heifer

A two-year-old Braunvieh heifer was presented with a traumatic luxation of the second phalanx of the medial digit and concurrent subluxation of the second phalanx of the lateral digit of the right hindlimb. Closed reduction of both luxations was possible. Surgical arthrodesis was achieved using one narrow 4.5 mm three-hole equine locking compression plate for each joint. Placement of the bone plates resulted in stable arthrodesis of both proximal interphalangeal joints of the right hindlimb but there was persistent residual lameness. The heifer delivered a healthy calf but was slaughtered eight months after surgery because of varus deformity of the contralateral limb. Radio-graphs taken post-mortem revealed pronounced periosteal reactions involving both proximal interphalangeal joints and only partial bony bridging of the joint spaces.

Evaluation of intravenous regional anaesthesia and four-point nerve block efficacy in the distal hind limb of dairy cows

Background

Intravenous regional anaesthesia (IVRA) and hindfoot four-point nerve block anaesthesia (NBA) are recommended for local anaesthesia (LA) in the distal limb of dairy cows. Two studies were conducted to compare the efficacy, time until onset and stress responses to IVRA and NBA in dairy cows. In the first cross-over designed study, eight healthy unsedated German Holstein cows, restrained in lateral recumbency (LR) on a surgical tipping table, were treated with IVRA and NBA using procaine 2% as a local anaesthetic. Distal limb desensitization was tested by electrical (e-), mechanical (m-) and thermal (t-) nociceptive stimulation 10 min before and 15 and 30 min after LA. Hormonal-metabolic (blood concentrations of cortisol, lactate, non-esterified fatty acids, and glucose) and cardio-respiratory (heart and respiratory rate, mean arterial blood pressure) stress responses to treatment were assessed at predetermined intervals. In the second study, six healthy, unsedated German Holstein cows in LR were treated (crossover design) with IVRA and NBA. Short-interval e-stimulation was measured by the time until complete distal limb desensitization.

Results

In the first study, four of eight cows responded to e-stimulation 15 min after IVRA, while none of the cows treated with NBA responded until the safety cut-off level was reached. E-stimulation revealed complete desensitization of the distal limb 30 min after LA in all cows. Half of the cows did not respond to m- and t-stimulation before LA, so no further evaluation was performed. Stress reactions to IVRA and NBA treatment were similar, but differences may have been masked by stress response to LR restraint. In the second study, complete desensitization was achieved 12.5 min after NBA, while one of the six cows still responded to e-stimulation 20 min after IVRA.

Conclusion

Hindfoot nerve block anaesthesia and intravenous regional anaesthesia induced complete desensitization of the distal hind limb in dairy cows. However, the anaesthesia onset after NBA was significantly faster than that of IVRA, which may be clinically relevant in the field, particularly when distal limb anaesthesia is required for major claw surgeries under time constraints.

Limb amputation and prosthesis

Limb amputation is an alternative to euthanasia when catastrophic injury prevents successful restoration of the limb or when cost is an issue. Proximal limb disarticulation for amputation is preferred if a prosthesis is not considered. Distal amputations are needed to accommodate exoskeletal prosthesis. This article reviews the considerations and describes techniques for this surgery.

Surgical diseases and techniques of the digit

Claw diseases in cattle are common under field conditions. Sole ulcer, sole abscess, foot-rot, digital dermatitis, and interdigital dermatitis are frequently diagnosed and treated by owners, foot trimmers, and veterinarians. Most digital surgical conditions are manageable in field conditions; however, some postoperative care is more demanding and, therefore, prevents some veterinarians from performing such techniques in field conditions. Even if most techniques are easy to perform, nevertheless surgical decision making, perioperative treatment, and pain management can be more challenging than the technique itself.

Antimicrobial issues in bovine lameness

This article reviews some of the issues surrounding antimicrobial use in treating diseases that cause lameness in cattle. The discussion includes sections on selection of an antimicrobial, regimen design, and medication of multiple animals. Pathogen susceptibility testing is covered, along with empiric selection of antimicrobials. Other issues covered include regional perfusion and topical application of antimicrobials, antimicrobials in footbaths and in feed, and withdrawal time estimates.

Synovial fluid analysis in cattle: a review of 130 cases

OBJECTIVE

To compare synovial fluid characteristics of cattle with infectious and noninfectious arthritis.

STUDY DESIGN

Retrospective cohort study.

ANIMAL OR SAMPLE POPULATION

130 cattle.

METHODS

Synovial fluid was analyzed for total nucleated cell count (NCC), absolute number and percentages of polymorphonuclear (PMN) and mononuclear cells, total protein (TP) concentration, and specific gravity. Cattle were categorized as having infectious or noninfectious arthritis based on physical and lameness examinations, joint radiographs, and microbial culture results. Kruskal-Wallis 1-way analysis of variance was used to compare synovial fluid analysis data from different categories. Selection of cut-off values for the calculation of likelihood ratios, sensitivity, specificity, and positive and negative predictive values was based on examination of the distribution of the data using histograms.

RESULTS

Cattle with infectious arthritis had significantly higher numbers of total NNC, PMN cells, TP concentration, and specific gravity (P = .0001) and a significantly higher percentage of PMN cells compared with cattle with noninfectious arthritis (P = .0001). The percentage of mononuclear cells was significantly higher in cattle with noninfectious arthritis (P = .0001).

CONCLUSIONS

Synovial fluid analysis is useful for differentiation of infectious and noninfectious causes of joint disease in cattle.

CLINICAL RELEVANCE

Cattle with a synovial fluid total NCC > 25,000 cells/microL, a PMN cell count > 20,000 cells/microL or more than 80% PMN cells, and TP > 4.5 g/dL should be considered to have infectious arthritis.

Use of a multifenestrated indwelling lavage system for treatment of septic digital tenosynovitis in cattle

Septic tenosynovitis was diagnosed in seven cattle on the basis of history, physical examination, radiographs, cytological examination of tendon sheath fluids, and microbial culture. A commercially available indwelling multifenestrated silicone rubber drain was used to perform frequent lavage of the flexor tendon sheaths. The sepsis resolved in all cattle. Five of six cattle for which long-term (> 1 year) follow-up information was available were clinically sound on the affected limb and had remained productive members of the herd.