DEVELOPING A TECHNIQUE FOR ULTRASOUND-GUIDED INJECTION OF THE ADULT CANINE HIP

Establishment of an ultrasound-guided protocol for the assessment of hip joint osteoarthritis in rabbits-A sonoanatomic study

Ultrasound (US) has emerged as one of the most applied imaging tools to diagnose musculoskeletal disorders and assist in guided intra-articular administrations. Nevertheless, in evaluating the rabbit hip joint, there is a need for an ultrasonographic approach. Therefore, this study aimed to describe the hip sonoanatomy, develop and validate a US-guided protocol to assess the hip joint in rabbits and apply this protocol in vivo. This study was carried out in three phases, phase I: a pilot cadaveric study, to assess the applicability of different US approaches in the hip of rabbits and, consequently, develop a detailed US-guided protocol (2 rabbit cadavers, n = 4 hips); phase II: validation of the established US-guided protocol through a numerical scoring system in healthy joints (11 rabbit cadavers, n = 22 hips), and, lastly, phase III: application of the US-guided protocol in vivo in osteoarthritic joints (5 rabbits, n = 5 hips). A total of six planes were validated, two in the ventral approach and four in the dorsal approach. The ventral transverse plane was deemed more informative regarding the hip joint sonoanatomy, enabling the identification of a greater number of structures when compared to the other planes. Nevertheless, this study suggested that the isolated application of a plane was deemed insufficient for a complete and detailed evaluation of the hip joint anatomy, rendering it necessary to employ other planes complementarily. Furthermore, the established US-guided protocol allowed a definitive diagnosis of OA, and osteophytes and capsular hypertrophy were among the defects most frequently detected. This novel study provided US anatomical landmarks for forthcoming therapeutic research and monitoring of OA development, granting the accurate identification of osseous and cartilaginous defects.

Ultrasound is an accurate method compared to radiography for diagnosing the presence of acute hip luxation in cadaver dogs and can identify the direction of luxation with variable reliability

Acute hip luxation is a common musculoskeletal injury in dogs, with radiographs being the preferred imaging modality for confirming the diagnosis. In large animal and human medicine, ultrasound is often utilized for this purpose. The objectives of this three-part study were to utilize a canine cadaver model to establish ultrasonographic features of hip luxation and evaluate the accuracy and reliability for diagnosing hip luxation with ultrasound. For the first prospective, exploratory study, a cadaver model was developed that allowed manual luxation and subsequent ultrasonography of the hip joint while in four directions of luxation. For the second prospective, anatomic study, a description of the ultrasonographic features for each direction of luxation was created. For the third prospective diagnostic accuracy, observer agreement study, 16 residency-trained and intern veterinarians without prior experience in this technique performed randomized, repeated ultrasound exams on cadaver hips assigned as normal or luxated (equally distributed between the 4 directions). A total of 1140 hip ultrasounds were performed with good accuracy (median, 90.8%; range, 61.4-100%), sensitivity (89.5%), and specificity (80.0%) for diagnosing the presence of hip luxation. Accuracy for identifying the correct quadrant of luxation was significantly lower (mean, 58.6%; range, 24.6-90.8%; P < 0.001). Intraobserver accuracy agreement varied widely from none to almost perfect agreement, and interobserver agreement ranged from slight to moderate agreement. The results of this study supported the use of ultrasound for diagnosing the presence of hip luxation but did not support replacing radiographs for diagnosing the direction of luxation.

Orthopedic Imaging: A Practical Clinical Guide

Many imaging options are available to the practitioner both in-house and on a referral basis to help make a definitive diagnosis for orthopedic injuries. To guide treatment, a complete understanding of the nature and extent of the injury is ideal. While a thorough orthopedic physical examination is the first step, a complete diagnostic work-up will include at least one and often more than one imaging modality. The goal of this article is to discuss the imaging options for some of the more common orthopedic issues encountered in dogs to help guide the practitioner through the selection of which should be considered to accomplish a diagnosis.

Joint Injection Techniques and Indications

Indications for injecting synovial joints may include diagnostic, therapeutic, or combination. Diagnostic injectates aim to reduce or eliminate the contribution of pain to lameness and may be assessed both subjectively or objectively by the clinician. Diagnostic joint injections are not specific for a disease and their limitations must be remembered when interpreting a response-including false-negative results. Patient selection and sterile technique throughout the procedure minimize adverse effects. Risks of intra-articular (IA) injections may include transient soreness, cartilage damage, and, rarely, septic arthritis. Ultrasound guidance with a trained clinician may provide further benefits including the reduction of periprocedural discomfort, reduction in iatrogenic cartilage damage during needle insertion, and improvement in synovial fluid feedback. The removal of some synovial fluid before administering an IA injection should be considered to confirm needle placement, provide diagnostic sampling, and help accommodate injectate volume.

Accuracy and Feasibility of Ultrasound-Guided Intra-articular Injection of the Rat Hip Joint

Intra-articular injection is frequently used as an effective diagnostic and treatment tool for hip joint diseases. However, the underlying treatment mechanism remains unclear because of a lack of experimental animal models. A challenge facing researchers is how to accurately and consistently perform injections involving animal hip joints. The purpose of this study, then, was to establish an ultrasound (US)-guided intra-articular (IA) injection technique using rat hip joints and to evaluate its accuracy and feasibility versus a fluoroscopy (FL)-guided technique. For this study, 20 US-guided and 20 FL-guided IA injections were administered to separate groups of Sprague-Dawley rats. For each procedure, 50 μL of iohexol was injected into the hip joint using a 25G needle. The US-guided injections were performed using a linear probe, and the FL-guided IA injections were performed using C-arm X-ray fluoroscopy. All injections were verified by computed tomography imaging. The number of successful injections and needle repositions per injection, as well as operating times, were recorded, and the rats were observed for complications for 10 d after the injections. Statistical analysis was used to compare US-guided and FL-guided techniques with significance set at p < 0.05. The success rate was markedly higher for the US-guided interventions (90%) than for the FL-guided interventions (75%) (p<0.05). The intervention time was shorter in the US-guided group (95.95 ± 8.376 s) than in the FL-guided group (110.70 ± 20.236 s) (p < 0.05), and the median number of needles repositioned per injection in the US-guided group (1.20 ± 0.41) was notably less than that in the FL-guided group (1.60 ± 0.68) (p < 0.05). A puncture site hematoma was noted in two rat hips (10%) the day after injection in the FL-guided group. Overall, the study indicated that ultrasound-guided intra-articular injection of the hip is a feasible, accurate and safe method for use in rats. This makes it a promising tool for diagnosing coxofemoral pain, producing hip osteoarthritis animal models and administering intra-articular medication.

Transcutaneous Ultrasound Guided Intraovarian Injection in Rats (Rattus norvegicus)

The goal of this study was to develop a method for ultrasound-guided percutaneous intraovarian injection in Wistar rats.Intraovarian administration of chemicals or needle aspiration of the ovary has been undertaken in some species, includinghumans, equines, and bovines. In rodents, which are widely used in scientific research, a technique for intraovarian injectionwithout surgical exposure of the organ has not been described. The current study standardized the procedure of ovarianpercutaneous injection of 0.9% sodium chloride guided by ultrasound in rats. The ovaries were measured by ultrasoundimaging before and immediately after injection and showed a significant increase in ovarian length but not width. No clinical abnormalities were detected within 15 d after injection. These findings indicate that the steps of ultrasound localization of the organ, digital restraint, and correct needle insertion achieved successful intraovarian administration of saline without invasive surgery. These results document the feasibility of ultrasound-guided intraovarian percutaneous injection in rats and may be useful for future research on female reproduction and chemical sterilization.

Accuracy of Ultrasound-Guided versus Landmark-Guided Intra-articular Injection for Rat Knee Joints

Our aim was to test the effectiveness of ultrasound-guided intra-articular (IA) injection into the knee joint of rodents by an inexperienced operator compared with standard landmark-guided IA injections by a trained injector. Fifty landmark-guided and 46 ultrasound-guided IA injections in 49 rats were analyzed. Animal positioning and injection protocol were designed for use with the ultrasound system. Injection delivery was verified with a secondary imaging modality. We compared the success of IA injections by method (landmark and ultrasound-guided), adjusting for all other confounding factors (age, weight, experience, laterality and presence of surgery). Ultrasound-guided injections had higher success rates overall (89% vs. 58%) and helped to reduce the number of failed attempts per injection. None of the cofounding factors influenced the success of injection. In conclusion, we found higher accuracy for ultrasound-guided IA injection delivery than the traditional landmark-based injection method and also the technical feasibility for untrained personnel.