Distal Interphalangeal Joint Arthrodesis in Seven Cattle Using the Acutrak Plus Screw

Objectives— To report a technique for arthrodesis of the distal interphalangeal joint (DIPJ) with two 6.5 mm Acutrak Plus (AP) compression screws from a solar approach and outcome in 7 cattle.
Study Design— Case series.
Animals— Cattle (n=7) with DIPJ arthritis.
Methods— Retrieved data from medical records of cattle that had undergone DIPJ arthrodesis using 2 AP screws via a solar approach were signalment, history, clinical signs, preoperative blood work, preoperative radiographs, complications, postoperative radiographs, and postoperative lameness evaluation. Outcomes, assessed by owner interview 6–26 months after surgery, were classified as excellent, good, or poor.
Results— Fusion of the DIPJ was evident by 6 months. All cattle returned to full function with minimal lameness and normal appearance to the distal aspect of the limb. Four thoracic limbs and 3 pelvic limbs were affected; 3 medial and 4 lateral claws. Complications included moderate lameness associated with implants (n=2) that resolved after screw removal.
Clinical Relevance— Use of the AP screw system in cattle is an excellent option for DIPJ arthrodesis with minimal postoperative morbidity and excellent return to function.     

Use of an intra-uterine glass ball protocol to extend luteal function in mares

A 25- or 35-mm diameter glass ball was placed in the uterus of mares to observe the effect on interovulatory interval, luteal function, estrous behavior, the endometrium, and subsequent fertility. The 25-mm glass ball was spontaneously expelled from the uterus of 6 of 12 mares (50%), whereas none of the 35-mm glass balls was expelled. Teasing results were consistent with the concentration of circulating progesterone. Luteal function was extended in 7 of 18 mares (39%) maintaining a glass ball, whereas an extended luteal period occurred in 4 of 32 mares (13%) observed as controls. Extended luteal function occurred in 7 of 62 diestrus periods (11%) among mares following ball placement, whereas 4 of 50 diestrus periods (8%) were extended in control cycles. The mean luteal life span in mares with a glass ball and extended luteal function was 87 days (range, 76 to 109 days); there were no significant differences in length of luteal function in both groups of mares that received the 2 different ball sizes. Endometrial changes observed between preplacement and postremoval samples were minimal. When mares were bred in the season subsequent to glass ball removal, 17 of 23 (74%) conceived. Placing an intrauterine glass ball in a mare may be an alternative to exogenous hormone therapy to prevent cycling in some mares. Luteal function was extended to nearly 90 days in approximately 40% of mares. The 35-mm diameter glass ball appeared to have an advantage for retention over the 25-mm size. Results of our study could not completely rule out idiopathic persistence of the corpus luteum as an explanation for the extended luteal function observed in mares with a glass ball. Readers are cautioned that many questions still exist about the use of intra-uterine glass balls in mares. Further work is required to confirm the efficacy of the use of an intra-uterine glass ball for prolonged luteal function in mares and to identify its mechanism of action.

Introduction

In recent years, there has been a debate among veterinary practitioners concerning the efficacy of various extra-label uses of progestin products (eg, cattle growth implants and human depo-progestin injectables) to modify behavior in mares. Clients who own horses are more frequently seeking means to suppress behavioral signs of estrus, expecting that with such suppression the mare will train or perform better. Requests for these progestin products by mare owners puts veterinary practitioners in the precarious situation of using pharmaceuticals, extra-label, without scientific evidence of efficacy, in mares.In reality, the only truly effective means of suppressing behavioral signs of estrus in most intact mares is to maintain sufficient concentrations of circulating progesterone or its equivalent. Today the only efficacious way to maintain a sufficient level of progesterone or its equivalent is for the mare to have a functional corpus luteum (CL), administer exogenous progesterone (eg, ≥50 mg in oil, intramuscularly, daily), or administer daily synthetic progestins (eg, altrenogest [Regumate], Hoechst Roussel Vet, Warren, NJ).^{1, 2 and 3}Recently, placement of a glass ball of 30-mm diameter in the uterus has been suggested as a reversible means of preventing mares from cycling and displaying behavioral signs of estrus (message to Equine Clinicians Network, Dr Randy J. T. de Greef, March 19, 2000). If this technique is effective, it would be of value to mare owners because it would eliminate the need for daily treatments over extended periods.We have been unable to find literature that would support or refute this idea in horses. However, the effects on ovarian function, body weight gain, and pregnancy rate in nulliparous heifers of a copper-bearing intrauterine device were studied.⁴ The researchers reported that the heifers receiving the intrauterine device had lower progesterone concentrations than did control subjects. Nevertheless, nearly all of the treated heifers had better weight gain, were anestrus, and did not become pregnant during the study; however, multiple ovarian follicular cysts developed in many of them. The idea of using an intrauterine device to suppress estrus is said to have originated centuries ago in the Middle East as a common means of keeping camels from cycling and becoming pregnant (personal communication, Dr Ahmed Tibary, College of Veterinary Medicine, Washington State University, Pullman, Wash, May 2000).To our knowledge, the efficacy and long-term effects of glass ball treatment have not been critically evaluated. Our objectives in this study were to observe the effect of placement of an intra-uterine glass ball on interovulatory interval, luteal function, estrous behavior, the endometrium, and subsequent fertility of mares.

Materials and methods

Animals

A total of 38 light-horse breed mares ranging in age from 3 to 20 years were used for this study. Mares were maintained in accordance with the Guide for the Care and Use of Agricultural Animals in Agricultural Research and Teaching (1st revised edition, January 1999). All experimental procedures involving animals were approved by the Institutional Animal Care and Use Committee at Auburn University (IACUC Protocol No. 0308-R-2307).

Intra-uterine device

Two glass ball (www.glassmarbles.com) sizes, 25- and 35-mm diameters, were evaluated in this study (Fig 1).

Limb Sparing Using a Double Bone-Transport Technique for Treatment of a Distal Tibial Osteosarcoma in a Dog

OBJECTIVE: To evaluate the treatment of a spontaneously occurring osteosarcoma in a dog by means of tumor resection and bone regeneration of a 12-cm defect using double bone transport. STUDY DESIGN: Case report. ANIMALS OR SAMPLE POPULATION: An 11 year-old client-owned German shepherd. METHODS: After tumor resection, a preassambled Ilizarov frame was secured to the proximal tibia and to the tarso-metatarsal region. Two osteotomies were performed in the proximal metaphysis. The two bone segments were transfixed with 1.5-mm-diameter wires, each secured to a ring, and bone transport was performed until the distal segment reached the talar surface. Cisplatin was administered 14, 35, and 59 days after surgery. RESULTS: Bone regenerate was first visible radiographically 4 weeks after surgery. The frame was removed 162 days after surgery. The hock was protected with a plaster cast because the tarsal arthrodesis was not complete. The dog underwent tibiotarsal arthrodesis 201 days after osteosarcoma resection. The dog died of metastatic disease 239 days after the initial surgery. CONCLUSIONS: Even though this dog died of systemic metastases, local recurrence did not develop. Cisplatin chemotherapy did not appear to negatively affect bone regeneration. CLINICAL RELEVANCE: To our knowledge, the double transport technique has not been previously described in the veterinary literature. In this dog, this technique decreased the duration of treatment compared with a conventional single-segment transport technique.     

The Effect of Six Knotting Methods on the Biomechanical Properties of Three Large Diameter Absorbable Suture Materials

Objective— To evaluate the effect of 6 different knotting methods on the mechanical properties of 3 large absorbable suture materials used in large animal surgery. Study Design— In vitro mechanical study. Sample Population— Knotted suture loops (n=15 per group). Methods— Suture loops were created between two low‐friction pulleys with either 2 polydioxanone, 2 polyglactin 910 or 3 polyglactin 910. Strands were tied using 1 of 6 knotting technique: square knot, surgeon knot, clamped surgeon's knot, sliding half‐hitch knot (HH), Delimar knot and self‐locking knot (SLK). A single cycle to failure test was performed on each suture loop with a distraction rate of 100 mm/min. Failure modes were evaluated and breaking strength, elongation to failure and stiffness were compared. Results— All loops except two HH failed at the knot by acute breaking. The double‐stranded SLK was both stronger and stiffer than all other knots for each suture material. Clamping the first throw of the surgeon knot decreased load to failure significantly (143.11 ± 8.64 N) compared with not clamping (159.21 ± 6.14 N) for polydioxanone. Stiffness and elongation to failure were respectively lower and increased for 2 polydioxanone compared with both polyglactin 910 materials for all knotting techniques. Conclusions— Knotting techniques do influence structural properties of suture loops. The double strand loop conferred stiffer and stronger properties to the SLK Clinical Relevance— Clamping the first throw of polydioxanone should be avoided when tying a suture under tension even using large diameter suture materials. Using a SLK might be considered as a useful alternative when excessive tension is present.