Treatment options, complications and long-term outcomes for limb fractures in pet rabbits.

BACKGROUND: Limb fractures represent the most common orthopaedic disease in pet rabbits. However, only a few studies have evaluated therapeutic details of limb fractures. There are no data available for long-term outcomes of limb fracture treatment. METHODS: The medical records of six institutions were reviewed retrospectively to identify cases of traumatic limb bone fractures in pet rabbits between 1999 and 2020. The medical records (n = 387) were analysed for details of fracture prevalence, aetiology, therapy protocols, treatment complications, outcome and long-term effects. In addition to the retrospective data evaluation, 13 rabbits were re-evaluated in person in recent clinical analyses, including orthopaedic examination, radiography and computed-tomographic imaging. Details of long-term effects of fracture treatment were requested over the telephone for a further 232 animals using a standardised questionnaire. RESULTS: Long bone fractures accounted for the majority of all fractures (296/387; 76.5%). Hindlimb fractures (301/387; 77.7%) were more common than forelimb fractures (86/387; 22.2%), and tibial fractures and combined fractures of the tibia and fibula (119/387; 30.8%) were observed most frequently. Most fracture treatments were based on osteosynthesis procedures (243/328; 74.1%). Treatment complications occurred in 130 out of 328 (39.6%) cases. A high bodyweight (p = 0.047) and an older age (p = 0.01) were found to be significant risk factors for the emergence of therapy complications. Overall, 75.4% of animals (175/232) had a satisfactory long-term outcome. Limb posture anomalies were evaluated in 61 cases (26.3%). LIMITATIONS: The multi-centre approach led to the inclusion of various institutions, veterinarians, treatment protocols and rabbit populations that might have influenced the results. The medical records were reviewed retrospectively, so there were some data that were lacking or could not be collected in a standardised manner. Furthermore, rabbit owners' evaluation of long-term outcomes might be prone to error, despite the use of a standardised interview questionnaire. CONCLUSION: Limb fractures are a common orthopaedic issue in pet rabbits. The patient's bodyweight and age are significant risk factors for the emergence of complications during the fracture treatment process. Long-term orthopaedic effects, such as abnormal limb posture and permanent lameness of the affected limb, were observed regularly.

The in-air auditory thresholds of the eurasian otter (Lutra lutra, L. 1758) as determined by auditory brainstem responses.

As of yet there is no literature record of the hearing range of the Eurasian otter (Lutra lutra, L. 1758), a key species for natural conservation efforts in Europe. We recorded in-air pure tone hearing thresholds of anaesthetized otters using auditory brainstem responses (ABR) and report the results of the Eurasian otter. The recorded potentials showed the typical mammalian auditory brainstem response consisting of 5 distinct positive peaks during the first 10 ms after stimulus onset. At 80 dB SPL the hearing ranged from around 200 Hz to 32 kHz, with lowest thresholds around 4 kHz.

[Osteolysis of the hip joint in an eastern river cooter (Pseudemys concinna concinna)]. / Osteolyse des Hüftgelenks bei einer Hieroglyphen-Schmuckschildkröte (Pseudemys concinna concinna).

Lameness in freshwater turtles is rarely seen and is mostly caused by bite injuries, other traumata or inflammatory processes. A 17 year old female eastern river cooter which was pretreated for disseminated shell necrosis a few months ago was presented due to acute lameness of the right hind limb. Diagnostic imaging revealed complete lysis of the hip joint and was classified as necrotizing osteomyelitis by histopathology. Septicemic spreading of pathogens and thus a link to the previous shell necrosis could not be identified. The patient developed wound complications and died a few days after the surgical procedure. Postmortem, a pronounced subacute pneumonia was diagnosed as presumed cause of death, which has not been clinically manifest during the whole medical history.

A new bending stiffness measurement device to monitor the influence of different intramedullar implants during healing period.

To manage fractures in long bones, intramedullar implants, plates or external fixators are often used. In many cases, the implants are removed after bone consolidation. X-ray images are normally used to monitor bone formation and to determine the point of return to full load bearing and removal of the implants. However, plain radiographs give only inaccurate information about the degree of healing progress. Known quantitative methods as QCT, DEXA, etc. provide information about bone density which certainly contributes to the mechanical properties of healing bone, but they do not provide a direct measurement of the stiffness of the healing callus. In this study we present an in vivo 4-point-bending stiffness device for small animals which is designed to directly monitor the progression of the healing process. The device was tested in a bone-defect model with different test-specimens chosen to simulate the stiffness of bone at different stages of healing. To verify the results, it was tested in an animal fracture study in rabbits during the healing period with and without an intramedulary implant. Both the test-specimen and bones of the in vivo study were compared with data in a materials testing system (MTS) in four-point bending. The device was found to have a high precision and significant in vitro and in vivo correlation with the MTS. The results suggest that this measurement device has the ability to monitor the healing process of bone and to analyse the influence of degradable implants on the mechanical behaviour of bone or bone metabolism effecting pharmaceutics.