Background: Autologous Platelet-Rich Plasma (PRP) is increasingly used for the treatment of intra-articular hip pathology. Accurate sub-capsular needle placement is critical for therapeutic efficacy, but can be technically challenging using conventional Ultrasound (US) guidance due to limited needle visualization in difficult to access deep joints. Contrast-Enhanced Ultrasound (CEUS) arthrography may improve real-time confirmation of intra-articular needle position. Case presentation: A man in their early 50s with a history of acute mechanical left hip pain and an MRI-confirmed labral tear who underwent autologous PRP therapy. PRP was prepared from 240 ml of whole blood, yielding approximately ~40 billion platelets with a high leukocyte concentration and no exogenous activation. Injection was performed under US guidance using microbubble contrast to generate a CEUS arthrogram of the joint. Results: Prior to contrast entry, needle visualization was limited on B-mode and contrast-specific US imaging. Following intra-articular contrast dispersion, the joint space became markedly hyperechoic, allowing clear delineation of joint anatomy and improved visualisation of the needle shaft and tip. This enabled confident confirmation of intra-articular needle placement before PRP delivery. Conclusion: CEUS arthrography improves real-time needle visualisation and confirmation of intra-articular access during ultrasound-guided hip injections. This technique may enhance procedural accuracy and safety for PRP delivery in deep joints.

Ground-glass nodules (GGNs), early signs of lung adenocarcinoma, increasingly require minimally invasive diagnosis due to expanded health screening. This study evaluates the mobile 3 D Cios Spin system (initially for orthopedics) in achieving integrated localization and resection of pulmonary nodules. This retrospective study analyzed 23 consecutive patients who underwent thoracic procedures at the Department of Thoracic and Cardiovascular Surgery, Fourth Affiliated Hospital of Soochow University (Dushu Lake Hospital), from January to December 2023, based on electronic medical records and operative reports. Before surgery, all pulmonary nodules were identified via low-dose or non-contrast chest CT and confirmed to persist over ≥3 months. The localization needle was precisely placed (needle within ≤5 mm of nodule margin confirmed intra-operatively) with no intraoperative dislodgment. Data collection focused on demographics, procedural details, and perioperative outcomes to evaluate the intervention's feasibility and safety. Preoperative localization achieved 100% technical success, defined as accurate placement of the localization needle within ≤5 mm of nodule margin confirmed intra-operatively. Peri-procedural complications included one pneumothorax (4.3%) during needle insertion. Positioning exceeded 45 min in two patients (8.7%) due to anatomical/imaging limitations; one (4.3%) required unguided resection without adverse outcomes. Mean durations: 35.3 ± 6.4 min (localization), 90.8 ± 20.2 min (surgery). All patients recovered uneventfully. No recurrence occurred at 6-month follow-up, but 2-year follow-up is required to assess long-term efficacy (retrospective follow-up ongoing). This case series supports the feasibility, safety, and clinical efficacy of combining pulmonary nodule localization and resection using the mobile 3 D C-arm Cios Spin system. Device/patient factors (e.g., system constraints) compromised localization in select cases, necessitating technical refinements and optimized selection criteria.

Feasibility of Robot-Assisted CT-Guided Interventions Compared with Conventional Technique: A Prospective, Randomized, Clinical Trial.

Transforaminal epidural steroid injections (TFESIs) are frequently used to treat lumbar and radicular pain. Although ischemic complications are extremely rare, their severity-often resulting in irreversible paraplegia-necessitates a thorough understanding of the anatomical and procedural risk factors. This review carefully examines the vascular anatomy of the lumbar intervertebral foramen, the distribution and risks associated with radiculomedullary arteries, and reported cases of severe complications related to lumbar TFESIs. Anatomical and radiological data indicate that radicular arteries are particularly rare below the L2-L3 level and are more common on the left side. The upper third of the intervertebral foramen, especially at T12-L3, is the most likely site of arterial involvement, raising concerns about the safety of traditional subpedicular approaches. Kambin's triangle appears to be a safer alternative, reducing arterial contact while still enabling effective drug delivery. The use of particulate corticosteroids, especially methylprednisolone and triamcinolone, is strongly associated with ischemic events owing to their larger particle sizes. Non-particulate options such as dexamethasone are preferred, particularly at higher spinal levels. Although rare, venous punctures and hematomas require vigilance and careful steroid selection. Test doses of local anesthetics remain controversial and do not provide clear protective benefits. Current evidence indicates that adjusting techniques-including needle placement, imaging guidance, and corticosteroid choice-can help reduce risks while maintaining the effectiveness of lumbar TFESIs.

<p><strong>Aim</strong> Unintended scaphoid excision is a rare but serious complication that can occur during surgical procedures involving the trapezium, including but not limited to trapeziectomy. Although prosthetic replacement is increasingly favored in the treatment of rhizarthrosis, trapeziectomy (with or without ligamentoplasty) remains a widely used and effective option. To reduce the risk of inadvertently removing the scaphoid, we rely on the anatomical intersection between the radial artery branch and the first dorsal compartment tendons as a landmark for identifying the scapho-trapezial joint. <strong>Methods</strong>In our Institutitonthe, Policlinico Universitario A. Gemelli IRCSS, we have been using a simple landmark to identify scapho-trapezial joint to teach residents: during surgery, after isolating the radial artery, a 16G needle is inserted at the intersection of the extensor tendons and the radial artery branch, followed by fluoroscopy to confirm needle placement in the scapho-trapezial joint. Patients were classified according to Eaton-Littler classification and the accuracy of the Landmark was then assessed among groups. <strong>Results </strong>So far we used the landmark on 212 patients. The distribution by Eaton-Littler stage was: 11 stage 1, 63 stage 2, 79 stage 3, and 33 stage 4. The reference point was accurate in 178 cases. No significant differences were found by sexgender or between stages 1, 2 and 3. However, accuracy in stage 4 was significantly lower (p<0.00001). <strong>Conclusion</strong>Our results confirm the reliability of this reference point, particularly in stages 1–3. While useful in stage 4, additional caution is required due to slightly reduced precision.</p>

Thoracic spinal anaesthesia (TSA) is gaining increasing recognition as a valuable regional anaesthetic technique in modern surgical practice, particularly for patients who are at high risk for complications associated with general anaesthesia. With the growing volume and complexity of surgical procedures worldwide, the demand for safer, targeted anaesthetic approaches has expanded. TSA involves intrathecal injection of local anaesthetic agents at thoracic vertebral levels, producing segmental sensory, motor, and sympathetic blockade suitable for a range of surgical interventions. Advances in anatomical knowledge and imaging modalities, especially MRI and ultrasound guidance, have improved the safety profile of this technique. Studies demonstrate a relatively wider posterior cerebrospinal fluid space in the thoracic region, offering a protective margin during needle placement. Although technical challenges exist due to narrow interlaminar spaces and angulated spinous processes, refined approaches such as paramedian insertion and optimal patient positioning enhance procedural success. Compared with general and lumbar spinal anaesthesia, TSA offers several advantages, including reduced cardiopulmonary complications, improved perioperative analgesia, attenuated surgical stress response, earlier return of gastrointestinal function, decreased postoperative nausea and vomiting, and shorter hospital stay. The use of lower doses of local anaesthetic also contributes to greater haemodynamic stability. TSA has been successfully employed in breast surgery, abdominal cancer procedures, laparoscopic cholecystectomy, nephrectomy, and selected thoracic surgeries, particularly in elderly and high-risk patients with compromised pulmonary function. Despite its benefits, potential complications such as hypotension, bradycardia, post-dural puncture headache, neurological injury, and infection must be considered. Careful patient selection, adherence to contraindications, and informed consent remain essential. Overall, TSA represents a safe and effective alternative anaesthetic modality with expanding clinical applications.

To assess the feasibility, safety, and accuracy of robotic needle placement for abdominal percutaneous interventions in a real-world, post-market setting. This prospective single-center study assessed a robotic guidance device for CT-guided needle placement during abdominal thermal ablation procedures. The primary endpoint was technical success, defined as successful robotic needle placement without technical failure (full manual insertion or two failed robotic attempts). Secondary endpoints included procedural safety, needle placement accuracy (3D deviation and manual adjustments categorized as minor [depth-only], moderate [lateral], andmajor [complete needle retrieval]), immediate ablation success, 2-month and 1-year local recurrence, and operator satisfaction (5-point Likert scale). Between April 2022 and January 2023, 54 patients (one duplicate inclusion excluded) were analyzed (30 men, 24 women); mean age 64.7 (± 12.9). Most had metastatic disease (74.1%). Target organs included mainly the liver (68.5%) and the kidney (24.1%). Mean lesion diameter was 24.7mm (± 13.1), with 59.0% considered technically challenging. Ablation modalities included microwave (63.3%), cryoablation (35.0%), and radiofrequency (1.7%). A total of 108 needles were placed (mean 1.8/patient), yielding a technical success rate of 94.4%. The mean final 3D accuracy after adjustments when required was 2.5mm (± 3.7). Immediate ablation success was achieved in 98.4% lesions (60/61), with a mean minimal margin of 5.6mm (± 3.2). Local recurrence occurred in 8.3% of cases at 2months and in 25.6% at 1year. Operator satisfaction averaged 3.1/4. Robotic guidance for CT-guided abdominal thermal ablation is feasible, safe, and provides high needle placement accuracy. Early oncologic outcomes appear comparable to conventional freehand techniques, supporting the integration of robotic systems into routine interventional radiology practice.

The stellate ganglion region is densely vascularized and innervated, making the stellate ganglion block (SGB) technically challenging under ultrasound, particularly for beginners. Deep learning can segment complex ultrasound anatomy, but its application to SGB has not been systematically assessed. We developed and validated a multilevel feature fusion UNet (MLF-UNet) to automatically delineate the SGB region on ultrasound, aiming to support accurate needle placement and improve procedural safety. In this retrospective study, 370 patients who underwent ultrasound-guided SGB between March 1, 2023 and January 16, 2025 were included. Three expert anesthesiologists jointly annotated 730 videos (2190 images) to produce ground truth. Data were split 9:1 by patient into development and heldout test sets. MLF-UNet was trained and compared with 5 benchmark models using identical pipelines. Test-set performance was evaluated with Dice similarity coefficient (DSC), Intersection over Union (IoU), 95th percentile Hausdorff distance (95HD), and average symmetric surface distance (ASSD). Three blinded experts rated model outputs (0-2 scale) for topological integrity, boundary precision, and background accuracy. For clinical validation and human-machine comparison, 3 additional experts and 3 nonexperts independently delineated SGB regions on the test set; spatial agreement was visualized with heat maps and assessed by Bland-Altman analysis. Metrics (DSC, IoU, 95HD, and ASSD) were compared among MLF-UNet, experts, and nonexperts. MLF-UNet achieved the best test performance: DSC 0.856 (95% confidence interval [CI], 0.846-0.865), IoU 0.754 (95% CI, 0.740-0.768), 95HD 3.98 mm (95% CI, 3.44-4.52 mm), and ASSD 1.08 mm (95% CI, 0.99-1.18 mm). Expert ratings favored MLF-UNet over all benchmark models for topological integrity (all P < .001), boundary precision (all P < .001), background accuracy (P < .01 or P < .001), and total score (all P < .001). Bland-Altman analysis showed a mean segmentation area difference between MLF-UNet and ground truth of -38.1 mm² (limits of agreement -278 to +202 mm²). MLF-UNet outperformed the nonexpert group on region overlap (DSC, IoU; both P < .001) and boundary precision (95HD, ASSD; both P < .001). Compared with experts, MLF-UNet showed no significant difference in overlap (DSC P = .332; IoU P = .125) but had slightly larger boundary precision (95HD and ASSD: both P < .001). MLFUNet outperforms 5 benchmark models and nonexpert clinicians for automated ultrasound segmentation of the SGB region, achieving expert‑level region overlap with a modest deficit in boundary precision.

Low-dose-rate (LDR) seed brachytherapy treatment planning systems (TPSs) can generate dose-optimized seed distributions; however, translating these plans into robot-executable needle insertions introduces additional geometric, anatomical, and robotic constraints that may limit clinical feasibility. This study presents an optimization framework for robotic-assisted LDR seed brachytherapy that refines needle trajectories based on preplanned seed distributions. The framework explicitly incorporates anatomical safety constraints and robotic feasibility requirements while aiming to preserve the original dosimetric quality. Simulation studies using thoracic and upper abdominal anatomical models show that the proposed method can generate clinically executable needle placements with minimal deviation from the planned seed positions. Phantom experiments further demonstrate the practical feasibility and placement accuracy of the optimized trajectories under robotic operating conditions. The proposed framework improves the feasibility and reproducibility of robotic-assisted LDR seed implantation in thoracic and related anatomical settings, offering a practical pathway toward safer and more reliable clinical deployment.

Cadaveric validation study. To evaluate the accuracy of a structured four-step ultrasound (US)-guided workflow for lumbar spinal level identification (SLI) using cadaveric specimens. Despite the routine use of fluoroscopic verification, wrong-level spinal surgery continues to be a documented and concerning complication. Fluoroscopy exposes patients and staff to ionizing radiation and requires specialized personnel and infrastructure. US has been utilized for SLI in obstetric and anesthetic applications but remains underexplored in surgical workflows. Ten fresh-frozen cadavers underwent US imaging to identify lumbar levels. A newly developed four-step protocol was employed: (1) Midline localization, (2) Sacral surface tracing, (3) S1-Superior articular process (SAP) recognition, (4) Interlaminar space enumeration. Five spinal needles were placed under US guidance in each specimen (L1-2 through L5-S1), with one needle per level. Fluoroscopic imaging was then used to confirm needle placement accuracy. A level was defined as misidentified if the projected trajectory from the needle tip violated predefined radiographic boundaries. A total of 50 lumbar levels were assessed across ten cadaveric specimens, with 25 procedures performed from the right side and 25 from the left. Fluoroscopic validation demonstrated accurate level identification in 49/50 cases, yielding an accuracy rate of 98%. The single misidentification occurred at the L5-S1 level during the third step of the workflow, where the S1 SAP was erroneously interpreted as the L5 inferior articular process. No systematic error patterns were observed, and the four-step protocol proved reproducible across specimens. This cadaveric feasibility study establishes a high accuracy of US-guided lumbar level identification. A structured and reproducible workflow for level localization was established, integrating a novel four-step protocol. These findings represent a first step toward a radiation-free alternative for preoperative lumbar level verification in spinal surgery. Further investigations are warranted to validate these results in clinical settings.

To evaluate the visualization of the ice ball during cryoablation of vertebral bodies and the bony pelvis in an in vivo swine model using virtual non-calcium imaging (VNCa) derived from photon-counting detector computed tomography (PCD-CT). Cryoablation was performed at six locations in the spine and pelvis of three live swine. Spectral ultra-high resolution image acquisition using PCD-CT was conducted before ablation and at 2, 4, 6 and 8min after initiation of the cryoablation cycle. Artifacts were suppressed using iterative metal artifacts reduction. Ice ball visualization within bone and soft tissue was assessed on both, conventional and VNCa images. At each time point the presence and size of the ice ball visualization was evaluated. A total of 12 needle placements was analyzed. In conventional images the ice ball could not be seen within bone at any time. In contrast, in VNCa images the ice ball became visible after 2min in all cases. However, the ice ball was less clearly visualized in the soft tissue on VNCa images. Mean ice ball volume at 2, 4, 6, 8min was 1.6 ± 0.9, 2.8 ± 1.7, 5.5 ± 2.9 and 8.3 ± 3.2ml in the vertebral bodies and 0.8 ± 0.3, 2.0 ± 0.4, 4.4 ± 0.6, 6.2 ± 1.1ml in the bony pelvis, respectively. PCD-CT enables early visualization of the ice ball within vertebral bodies and the bony pelvis in a swine model using VNCa images.

Dromedary camels (Camelus dromedarius) are vital to the socioeconomic and cultural fabric of arid regions, yet their healthcare is less developed than that of other domestic species. Their unique anatomy-including deep thoracoabdominal cavities, thick skin, and dense musculature-challenges conventional diagnostics and interventions. Ultrasound has emerged as a crucial, field-appropriate imaging modality, enabling rapid, non-invasive, real-time visualization of internal structures. This review examines ultrasound-guided diagnostic and therapeutic procedures in dromedary camels. Key diagnostic techniques, including thoracocentesis, abdominocentesis, portocentesis, and organ biopsies, are discussed with respect to clinical indications, protocols, advantages, and potential complications. Ultrasound guidance enhances accuracy and safety by ensuring precise needle placement, minimizing trauma, and improving diagnostic yield. Therapeutic applications, such as pleural effusion drainage and abscess evacuation, highlight ultrasound's role in minimally invasive alternatives to surgery. Camel-specific anatomical and behavioral factors influencing ultrasonography, including sternal recumbency and adapted equipment, are addressed. Ultrasound features that differentiate types of ascitic fluid-transudates, exudates, and hemorrhagic effusions-are critical for targeted treatment. It also aids in managing complex conditions such as uroperitoneum, peritonitis, and thoracic or abdominal effusions, with ultrasound-guided paracentesis improving differentiation between urinary bladder rupture and obstruction. Challenges remain due to camel anatomy, environmental conditions, sedation risks, and the need for trained operators. Future directions include developing camel-specific protocols, portable devices, AI-assisted and tele-guided diagnostics, and integration into veterinary education. Widespread adoption of ultrasound-guided interventions can enhance camel healthcare, animal welfare, and pastoral livelihoods in arid regions worldwide.

To demonstrate how to perform a venipuncture technique in small mammals using the proximal jugular vein, which may be useful when working with zoological companion and laboratory animals. Proximal jugular venipuncture can be performed in a variety of small mammal species. Heavy sedation or anesthesia is required. The patient is placed in dorsal recumbency and the skin disinfected. A small-gauge needle (typically, a 27-gauge needle or smaller is sufficient) on a 1- to 3-mL syringe is inserted 90° to the skin immediately cranial to where the clavicle inserts onto the manubrium. In species with small clavicles (eg, guinea pigs), the needle is inserted where the first rib connects to the manubrium. The needle is inserted to a depth of approximately 1 cm and slowly retracted with negative pressure. When a flash of blood appears in the hub, the needle is maintained at that depth by stabilizing the barrel. If the blood flow stops, the needle is gently inserted or retracted until it resumes. Pressure is held at the site after needle retraction. Proximal jugular venipuncture is performed with the immobilized patient in dorsal recumbency and utilizes palpable landmarks. Holding the needle at the successful depth by stabilizing the syringe barrel is key for blood collection, and it is important to hold pressure at the site after collection to prevent hematoma formation. Proximal jugular venipuncture is an option for collecting diagnostically useful volumes of blood in several small mammal species and provides palpable landmarks for needle placement while avoiding the need to utilize small peripheral veins or needle insertion into the thoracic cavity (eg, cranial vena cava venipuncture).

To determine the ideal location of a medial tenoscopic portal in the equine carpal flexor tendon sheath (CFTS) using contrast computed tomography (CT). Experimental cadaver study. A total of 20 entire forelimbs from adult Standardbred horses. Contrast media diluted in saline was injected into the CFTS from a lateral approach before manually flexing and extending the limb 20 times to disperse the contrast solution. The limbs were placed in lateral recumbency and a capped 21-gauge 1.5 inch needle was placed approximately 5 mm proximal and 32 mm caudal to the palpable distal medial radial physis into the medial aspect of the CFTS. Contrast CT was performed followed by tenoscopy using the conventional lateral approach. Gross dissection was then performed to determine if any damage was caused by needle placement. CT images were reviewed for impingement of intrathecal structures, the cephalic vein (CV) and the flexor carpi radialis tendon (FCRT). Neither intrathecal nor macroscopic superficial damage was caused by needle placement. Impingement of the FCRT and CV, identified on CT, occurred in seven specimens (35%) and one specimen (5%), respectively. The location for a medial tenoscopic portal was identified in the current study. Establishment of the location of a medial tenoscopic portal may help surgeons improve triangulation, egress and visualization of structures within the carpal sheath.

Epidural injection is used in pain intervention, requiring precise needle placement within the epidural space. Traditional techniques, such as loss of resistance and fluoroscopy-guided procedures, have limitations, including reliance on subjective assessment and radiation exposure. We proposed an optical force-sensing probe with an offset criterion of the needle tip-distal end to enhance the precision of puncture detection. The offset between the needle tip and the force-sensing probe is adjusted using a piezoelectric motor-based system with feedback position control. A Long Short-Term Memory model is also trained to detect the puncture. Insertion test on silicone phantom and ex-vivo specimens demonstrates that the system’s offset range for enhancing precision of puncture detection is between 0.6 mm and 1 mm. Compared to the offset in the previous study, the AUC score of puncture detection increased from 0.61 to 0.86. This approach secures the improvement of puncture detection reliability in robot-assisted epidural injection.

A 4-year-old intact male Golden Retriever with high fever (41°C/ 105.8°F), leukocytosis, and vomiting for 1 week, was presented for TCVM evaluation due to poor response to conventional therapy for pancreatitis. A TCVM pattern of Stomach Heat was diagnosed and daily acupuncture and oral Chinese herbal medicine was added to conventional therapy. Although anorexia remained, by the 3rd day of integrative treatment, the dog's body temperature had returned to normal and the vomiting had ceased. At the 4th daily acupuncture session, the dog developed an acute ocular disorder within 10 minutes of needle placement. This case challenges a reader's diagnostic and treatment skills to address the unusual clinical signs and design a TCVM treatment strategy.

Augmented Reality Visualization in Musculoskeletal Interventions: User Feedback and Ergonomic Impact on Needle Placement Procedures.

Accurate needle placement is essential for prostate biopsy. Recently, transperineal prostate biopsies are receiving renewed interest due to concern over infection from conventional transrectal biopsies. However, accurate needle placement is more challenging in the transperineal approach than in the transrectal approach due to the long insertion distance leading to a large targeting error and repeated insertion attempts. Improved procedure planning tools that can predict the deviation of the needle can potentially reduce the targeting error and number of insertion attempts. Prediction of deflection magnitude requires a model of biopsy needle deflection, which in turn requires information about tissue material properties. However, material properties of tissue in patients cannot be easily obtained. Accounting for this uncertainty in patient tissue properties requires a model capable of quantifying uncertainty in needle deflection as a function of a distribution of tissue properties. A Monte Carlo uncertainty quantification requires 1000s of samples, but it is not possible to obtain this many samples in a short enough time for intraoperative procedure planning using published needle deflection predictionmodels. This work seeks to develop a model of needle deflection fast enough for use in intraoperative procedure planning, validate this model against experimental results, and integrate it into a Monte Carlo uncertainty quantificationmodel. This work used a mechanics-based model of biopsy needle deflection to train a Fourier feature neural network (FFNN) model in order to make predictions with a low computational cost. Both models were validated against experimental data. The neural network model was used in a Monte Carlo uncertainty quantification model to quantify uncertainty in needle deflection arising from uncertain tissue mechanicalproperties. This work (1) implemented a mechanics-based model and a FFNN model. Both models were validated against previously published experiments carried out with tissue phantoms. Both models showed close agreement with the experimental data. (2) We showed that our FFNN model was more accurate than a baseline ordinary least squares model, introducing only about 0.3-mm tip deflection error compared to the mechanics-based model. We also showed that our FFNN model makes unbiased predictions with respect to the amount of deflection. (3) We demonstrated a Monte Carlo uncertainty quantification model of needle deflection with a low computational cost of about 20 CPU s. We used our uncertainty quantification model to show how the depth, stiffness, and magnitude of uncertainty in a layer of tissue affect needle deflection. In addition, we showed a simple clinical example of the use of our model. This work demonstrates a Monte Carlo uncertainty quantification model of needle deflection with a low computational cost. This method shows promise for future applications in procedure planning for prostate biopsies as well as other transperineal procedures conducted with flexible needles such as cryoablation andbrachytherapy.

The Inferior Alveolar Nerve Block (IANB) is the most utilized regional anesthetic technique in dentistry, but it carries a rare risk of transient Facial Nerve (CN VII) palsy, reported at approximately 0.3\%.This motor complication manifests as unilateral facial weakness, drooping of the corner of the mouth, and critical inability to close the ipsilateral eye (lagophthalmos). The primary etiology is a technical error: the inadvertent deposition of local anesthetic directly into the parotid gland capsule, a consequence of overly deep or posterior needle placement . While immediate palsy is a chemical conduction block, delayed presentation is hypothesized to stem from localized ischemic neuritis and secondary edema. Management is focused on immediate patient reassurance, mandatory ocular protection (lubricants and patching) to prevent corneal damage , and the use of systemic corticosteroids to mitigate inflammation . The prognosis is excellent, with complete functional recovery commonly observed within eight weeks. Prevention relies on rigorous adherence to injection protocol, including aspiration, slow injection, and strict depth control to prevent posterior needle penetration .

To provide a video tutorial on ultrasound-guided arthrocentesis and injection of the canine radiocarpal and tarsocrural joints. Dogs undergoing arthrocentesis or intra-articular injections for diagnostic or therapeutic purposes. The radiocarpal joint is visualized in long axis and the tarsocrural joint in short axis with a 70% isopropyl alcohol medium and linear array probe with a frequency range of 3 to 22 MHz and footprint of 25.5 mm after clipping a window and preparing the region sterilely. The needle is inserted, bevel up, in long axis with the probe angled at the appropriate trajectory to enter the visible joint space. The needle is advanced until the tip is visualized entering the joint. Aspiration to obtain synovial fluid can further confirm needle placement or provide diagnostic sampling prior to injection. The aspirate syringe is exchanged for that containing the therapeutic agent, and injectate can then be visualized entering and/or expanding the joint upon injection. Ultrasound-guided arthrocentesis will help to avoid surrounding vasculature and soft tissue structures, confirm needle placement, and target fluid pocketing. Needle guidance into a joint can reduce iatrogenic tissue damage from inappropriate needle placement and/or by minimizing attempts. For arthrocentesis, ultrasound guidance can maximize joint fluid volume acquisition for diagnostic purposes while avoiding blood contamination. For joint injections, ultrasound will help ensure intra-articular delivery of the injectate, particularly when synovial fluid aspirate feedback is inhibited (dry joint or obstructive synovial proliferation). Imaging guidance can help reduce iatrogenic tissue damage and procedure time.