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Abstract

Objective—To determine features, outcome, and complications of surgical treatment of camelid tooth root abscesses.

Design—Retrospective case series.

Animals—123 camelids with tooth root abscesses.

Procedures—Signalment, history, teeth involved, surgery performed, ancillary diagnostic tests, and short-term complications were recorded from each medical record. An owner questionnaire was used to obtain long-term (> 1 year) follow-up information.

Results—The most common surgical treatments included tooth extraction (n = 106) and apicoectomy (13). Owners provided follow-up information on 84 animals. Postoperative complications were reported in 42 of 84 animals. The most common complications included reinfection (n = 15), chronic draining tract (14), and osteomyelitis (14). Significantly more camelids that were in good or obese body condition at the time of surgery were alive at the time of follow-up, compared with those with thin body condition at the time of surgery. Camelids with 2 teeth extracted had significantly more complications than those with 1 tooth extracted. Thirty-four of 47 owners reported that they were completely satisfied with the outcome.

Conclusions and Clinical Relevance—Owners of camelids in poor body condition should be forewarned that such animals are at greater risk for complications following dental surgery. Clinicians should recognize that the number of teeth affected was not associated with a poorer outcome.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To compare the mechanical characteristics of polymerized caprolactam and monofilament nylon loops with those of the cranial cruciate ligament (CCL) in cattle.

Sample—6 femorotibial joints harvested from 3 cows and suture constructs made from No. 8 polymerized caprolactam, 80-lb test monofilament nylon fishing line, and 450-lb test monofilament nylon fishing line.

Procedures—Joints were cleared of soft tissue structures except the CCL, connected to a load frame, and loaded to failure while measuring force and elongation. Synthetic constructs tested in a similar manner included single-stranded and 3-stranded No. 8 polymerized caprolactam, 3- and 6-stranded 80-lb test monofilament nylon fishing line, and 3- and 6-stranded 450-lb test monofilament nylon fishing line.

Results—The CCL ruptured at a mean ± SD force of 4,541 ± 1,417 N with an elongation of 2.0 ± 0.3 cm. The tensile strength of 3-stranded 450-lb test monofilament nylon fishing line was similar to that of the CCL, rupturing at loads of 5,310 ± 369 N (braided strands) and 6,260 ± 239 N (parallel strands). Elongation was greater for braided constructs.

Conclusions and Clinical Relevance—The 3-stranded cords of 450-lb test monofilament nylon fishing line most closely approximated the strength of the CCL. Marked increases in elongation occur when large-sized materials are constructed in braided configurations, and this elongation would likely not provide stability in CCL-deficient stifle joints. Additional studies are needed to determine whether any of these materials are suitable CCL replacements in cattle.

Full access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Abstract

CASE DESCRIPTION

4 calves were evaluated because of lameness and an angular limb deformity of the metatarsophalangeal region.

CLINICAL FINDINGS

3 calves (ages, 5 days, 10 days, and 1 month) had a congenital varus deformity of the metatarsophalangeal region characterized by medial subluxation of the first phalanx of digits 3 and 4 at the metatarsophalangeal joints. A 6-month-old heifer had a valgus deformity of the metatarsophalangeal region secondary to a malunion of a Salter-Harris type II fracture. The degree of deformity angulation ranged from 16° to 54° for the 4 patients.

TREATMENT AND OUTCOME

A closing wedge ostectomy with transfixation pin–cast application was performed on the affected limb of all 4 patients. The ostectomy healed with only minor complications (disuse osteopenia distal to the transfixation pins [n = 4] and cast sores [1]) that were easily resolved with no long-term adverse effects. Duration of follow-up for the 4 patients ranged from 6 to 17 months, and the owners reported satisfactory ambulation with no (n = 2) or only mild (2) residual lameness in the affected limb.

CLINICAL RELEVANCE

Results suggested that a closing wedge ostectomy with transfixation pin–cast stabilization is an alternative for management of angular limb deformities of the metatarsophalangeal region in cattle. Such treatment improved the quality of life for all 4 patients. However, 2 of the 4 patients had congenital deformities confirmed to be heritable. There are ethical concerns associated with treating animals with heritable disorders, and exhibition and breeding of such animals should be avoided.

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To investigate the chondroprotective effects of autologous platelet-rich plasma (PRP), ampicillin-sulbactam (AmpS), or PRP combined with AmpS (PRP+AmpS) in an in vitro chondrocyte explant model of bovine Staphylococcus aureus–induced septic arthritis.

SAMPLE

Autologous PRP and cartilage explants obtained from 6 healthy, adult, nonlactating Jersey-crossbred cows.

ProcedureS

Autologous PRP was prepared prior to euthanasia using an optimized double centrifugation protocol. Cartilage explants collected from grossly normal stifle joints were incubated in synovial fluid (SF) alone, S aureus–inoculated SF (SA), or SA supplemented with PRP (25% culture medium volume), AmpS (2 mg/mL), or both PRP (25% culture medium volume) and AmpS (2 mg/mL; PRP+AmpS) for 24 hours. The metabolic activity, percentage of dead cells, and glycosaminoglycan content of cartilage explants were measured with a resazurin-based assay, live-dead cell staining, and dimethylmethylene blue assay, respectively. Treatment effects were assessed relative to the findings for cartilage explants incubated in SF alone.

RESULTS

Application of PRP, AmpS, and PRP+AmpS treatments significantly reduced S aureus–induced chondrocyte death (ie, increased metabolic activity and cell viability staining) in cartilage explants, compared with untreated controls. There were no significant differences in chondrocyte death among explants treated with PRP, AmpS, or PRP+AmpS.

CLINICAL RELEVANCE

In this in vitro explant model of S aureus–induced septic arthritis, PRP, AmpS, and PRP+AmpS treatments mitigated chondrocyte death. Additional work to confirm the efficacy of PRP with bacteria commonly associated with clinical septic arthritis in cattle as well as in vivo evaluation is warranted.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To improve upon the toggle-pin implant construction and develop a repeatable surgical technique to achieve coxofemoral stabilization in mature cattle.

ANIMALS

9 adult bovine cadaveric coxofemoral joints, 8 bovine femurs, 2 beef calf cadavers.

PROCEDURES

Ultimate tensile strength and elongation at failure were measured for the native ligament of the head of the femur (LOHOF) harvested up to 48 hours after death, and the prosthetic prototype utilizing stainless-steel cable and prosthetic prototype utilizing nylon leader line were compared. Bovine femurs were utilized to locate the ideal and repeatable trajectory of the prosthetic ligament to exit at the origin of the LOHOF. Using fluoroscopy, thawed calf cadavers with radiopaque markers placed at sites of origin and insertion of the LOHOF were positioned to assess limb angle to maximize joint isometry resulting in the ideal placement of the LOHOF prosthesis. The study was performed between February 1, 2020, and December 1, 2021.

RESULTS

The stainless-steel prototype had a significantly higher ultimate tensile strength and significantly decreased elongation at failure when compared to the LOHOF, while the nylon-based prototype had significantly decreased tensile strength and elongation at failure compared to the LOHOF. Therefore, neither prototypes were biomechanically similar to LOHOF.

CLINICAL RELEVANCE

The stainless-steel prosthetic prototype shows promise to provide superior stabilization to the luxated coxofemoral joint.

Open access
in American Journal of Veterinary Research

Abstract

OBJECTIVE To describe concentration-over-time data for ampicillin and sulbactam in the digital and systemic circulations and synovial fluid (SYN) of cattle following a single injection of ampicillin-sulbactam as a regional IV perfusion (RIVP).

ANIMALS 6 healthy adult nonlactating Jersey-crossbred cows.

PROCEDURES The right hind limb of each cow was aseptically prepared. A tourniquet was applied around the midmetatarsal region, and 1.0 g of ampicillin with 0.5 g of sulbactam in a combined formulation was administered as an RIVP into the dorsal common digital vein (DCDV). Blood samples from the DCDV and jugular vein and SYN samples from the metatarsophalangeal joint of the prepared limb were collected immediately before and at predetermined times for 24 hours after RIVP. One blood sample was obtained from the abaxial proper plantar vein of the lateral digit of the prepared limb 0.25 hours after RIVP. Serum and SYN ampicillin and sulbactam concentrations were determined by high-performance liquid chromatography.

RESULTS Mean ± SD maximum concentration of ampicillin in SYN and serum obtained from the abaxial proper plantar and jugular veins was 1,995 ± 1,011 μg/mL, 5,422 ± 1,953 μg/mL, and 2.5 ± 1.6 μg/mL, respectively. Corresponding serum and SYN concentrations of sulbactam were lower but followed the same pattern over time as those for ampicillin. Synovial fluid ampicillin concentration remained above 8 μg/mL for a mean time of 18.9 hours.

CONCLUSIONS AND CLINICAL RELEVANCE Potentially therapeutic concentrations of ampicillin were achieved in regional serum and SYN samples; SYN concentrations remained at potentially therapeutic values for > 12 hours following RIVP of 1.5 g of ampicillin-sulbactam in the hind limb of healthy cows.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To describe the pharmacokinetics of morphine, lidocaine, and ketamine associated with IV administration of a constant rate infusion (CRI) of a morphine-lidocaine-ketamine (MLK) combination to calves undergoing umbilical herniorrhaphy.

ANIMALS

20 weaned Holstein calves with umbilical hernias.

PROCEDURES

Calves were randomly assigned to receive a CRI of an MLK solution (0.11 mL/kg/h; morphine, 4.8 μg/kg/h; lidocaine, 2.1 mg/kg/h; and ketamine, 0.42 mg/kg/h) for 24 hours (MLK group) or 2 doses of flunixin meglumine (1.1 mg/kg, IV, q 24 h) and a CRI of saline (0.9% NaCl) solution (0.11 mL/kg/h) for 24 hours (control group). For all calves, the CRI was begun after anesthesia induction. Blood samples were obtained immediately before and at predetermined times for 120 hours after initiation of the assigned treatment. Noncompartmental analysis was used to estimate pharmacokinetic parameters for the MLK group.

RESULTS

During the CRI, steady-state serum concentrations were achieved for lidocaine and ketamine, but not morphine. Mean terminal half-life was 4.1, 0.98, and 1.55 hours and area under the concentration-time curve was 41, 14,494, and 7,426 h•μg/mL for morphine, lidocaine, and ketamine, respectively. After the CRI, the mean serum drug concentration at steady state was 6.3, 616.7, and 328 ng/mL for morphine, lidocaine, and ketamine, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

During the CRI of the MLK solution, steady-state serum concentrations were achieved for lidocaine and ketamine, but not morphine, likely owing to the fairly long half-life of morphine. Kinetic analyses of MLK infusions in cattle are necessary to establish optimal dosing protocols.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To assess the analgesic efficacy of an IV constant rate infusion (CRI) of a morphine-lidocaine-ketamine (MLK) combination in calves undergoing umbilical herniorrhaphy.

ANIMALS

20 weaned Holstein calves with umbilical hernias.

PROCEDURES

Calves were randomly assigned to receive a CRI of an MLK solution (0.11 mL/kg/h; morphine, 4.8 μg/kg/h; lidocaine, 2.1 mg/kg/h; and ketamine, 0.42 mg/kg/h) for 24 hours (MLK group) or 2 doses of flunixin meglumine (1.1 mg/kg, IV, q 24 h) and a CRI of saline (0.9% NaCl) solution (0.11 mL/kg/h) for 24 hours (control group). The assigned CRI was begun after anesthesia induction. A pain-scoring system and incisional algometry were used to assess pain, and blood samples were obtained to measure serum cortisol concentration at predetermined times for 120 hours after CRI initiation.

RESULTS

Mean pain scores did not differ significantly between the MLK and control groups at any time. Mean algometry score for the MLK group was significantly greater (calves were less responsive to pressure) than that for the control group at 4 hours after CRI initiation. Mean cortisol concentration decreased over time for both groups and was significantly greater for the MLK group than the control group at 1, 4, and 18 hours after CRI initiation.

CONCLUSIONS AND CLINICAL RELEVANCE

A CRI of MLK provided adequate postoperative analgesia to calves that underwent umbilical herniorrhaphy. However, the technical support required for CRI administration limits its use to hospital settings. Kinetic analyses of MLK infusions in cattle are necessary to establish optimal dosing protocols and withdrawal intervals.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To evaluate a novel prosthesis technique for extracapsular stabilization of cranial cruciate ligament (CCL)–deficient stifle joints in adult cattle.

SAMPLE

13 cadaveric bovine stifle joint specimens.

PROCEDURES

In the first of 3 study phases, the most isometric points on the distal aspect of the femur (distal femur) and proximal aspect of the tibia (proximal tibia) were determined from measurements obtained from lateromedial radiographs of a stifle joint specimen maintained at angles of 135°, 90°, 65°, and 35°. During phase 2, 800-lb-test monofilament nylon leader line was cut into 73-cm-long segments. Each segment was secured in a loop by use of 2, 3, or 4 crimping sleeves such that there were 12 replicates for each construct. Each loop was distracted to failure at a constant rate of 1 mm/s. Mean force at failure and elongation and mode of failure were compared among the 3 constructs. During phase 3, bone tunnels were created in the distal femur and proximal tibia at the isometric points identified during phase 1 in each of 12 CCL-deficient stifle joint specimens. The 3-sleeve construct was applied to each specimen. Specimens were distracted to failure at a constant rate of 1 mm/s.

RESULTS

Among the 3 constructs evaluated, the 3-sleeve construct was considered optimal in terms of strength and amount of foreign material. In phase 3, all replicates failed because of suture slippage.

CONCLUSIONS AND CLINICAL RELEVANCE

Use of 800-lb-test monofilament nylon leader line as a prosthesis might be a viable alternative for extracapsular stabilization of CCL-deficient stifle joints in adult cattle. Further in vivo studies are necessary.

Full access
in American Journal of Veterinary Research