RADIOGRAPHIC, COMPUTED TOMOGRAPHIC AND MAGNETIC RESONANCE IMAGING EVALUATION OF A CHRONIC LONG DIGITAL EXTENSOR TENDON AVULSION IN A DOG

Long digital extensor tendon avulsion is reported in a 5 month old Great Dane. Clinically the dog presented with a unilateral weight-bearing pelvic limb lameness. Joint effusion was present and there was pain and crepitance associated with flexion of the stifle. Orthopedic evaluation and radiographs were suggestive of a long digital extensor tendon injury which was confirmed by computed tomography and magnetic resonance imaging.The injury was surgically repaired with screw and spiked washer fixation.     

Caudal cervical intervertebral disk disease in the small dog: role of distraction and stabilization in ventral slot decompression

The clinical outcomes in 112 dogs weighing less than 35 pounds that were presented with cervical intervertebral disk protrusions were retrospectively evaluated. Although the second to third cervical (C2 to C3) intervertebral space was the most common site (27%) of disk protrusion, 57% of disk protrusions presented were caudal to the fourth cervical (C4) vertebra. Dogs with cranial intervertebral disk protrusions, including the C2 to C3 and C3 to C4 intervertebral disk spaces, responded favorably to ventral slot decompression. By comparison, caudal intervertebral disk protrusions (within the C4 to the seventh cervical [C7] intervertebral disk spaces) responded less favorably to ventral slot decompression, demonstrating significantly more severe clinical effects in motor function, comfort, recovery, and long-term outcome following surgery. Significant improvement in clinical results was seen in caudal disk protrusions when additional surgical distraction and stabilization were provided following ventral slot decompression.     

An in vitro biomechanical investigation of an intramedullary nailing technique for repair of third metacarpal and metatarsal fractures in neonates and foals

OBJECTIVE: To evaluate a dorsoproximal extra-articular approach for insertion of 8.25-mm, solid-titanium, intramedullary (IM) interlocking nails into ostectomized foal third metacarpal (MC3) and third metatarsal (MT3) bones; to compare the monotonic mechanical properties of IM nail constructs with paired intact bones; and to determine the effects of age, body weight, fore- or hindlimb, and left or right limb on the mechanical testing variables. ANIMAL OR SAMPLE POPULATION: Twenty bone pairs (10 MC3, 10 MT3) collected from 10 foals of various weights and ages. METHODS: One bone from each pair was randomly selected to be ostectomized and stabilized using an 8.25-mm, solid-titanium IM nail, and four 3.7-mm titanium interlocking screws (construct). Constructs and contralateral intact bone specimens were tested in axial compression and palmaro-/plantarodorsal (PD) 4-point bending. Monotonic mechanical properties were compared between intact specimens and constructs with an ANOVA; significance was set at P <.05. RESULTS: Nail insertion caused bone failure in 6 MC3 and 2 MT3. In general, mean mechanical testing values indicated that intact specimens were significantly stronger and stiffer than constructs for all age and weight ranges when tested in compression and PD 4-point bending (P <.05). Bone strength and stiffness of intact specimens tested in compression and bending tended to increase linearly with age and weight. CONCLUSION: IM interlocking nail fixation of gap-ostectomized MC3 and MT3 with 8.25-mm IM nails and 3.7-mm interlocking screws did not achieve sufficient strength or stiffness to be recommended as the sole means of repair for comminuted MC3 and MT3 fractures in young foals. CLINICAL RELEVANCE: IM interlocking nail fixation of foal cannon bone fractures may be useful to decrease soft-tissue disruption at the fracture site; however, there is a risk of bone failure associated with extra-articular insertion. This method should be combined with other forms of external coaptation for added stability in axial compression and PD bending.     

Fourth branchial arch defects in full‐siblings treated with a partial arytenoidectomy

Fourth branchial arch defects (4‐BAD) is a syndrome that consists of aplasia, or varying degrees of hypoplasia, of one or more of the cartilaginous or muscular structures derived from the fourth branchial arch, unilaterally or bilaterally. This case report describes the cases of 2 directly related siblings admitted with a complaint of abnormal respiratory noise at rest and complete exercise intolerance. Laryngeal palpation, resting upper airway (UA) endoscopy, lateral radiography of the larynx and cervical trachea, and laryngeal ultrasonography revealed multiple laryngeal and pharyngeal abnormalities. The clinical findings were compatible with the diagnosis of fourth branchial arch defects. A left partial arytenoidectomy and a unilateral ventriculocordectomy were performed in both cases. The follow‐up endoscopies revealed a functional airway aperture. The surgery enabled the horses to be used for riding. Considering the direct family relationship between the horses, these cases would support a genetic component of 4‐BAD.