Diagnostic and therapeutic joint injections

Safe and Effective Aspirations and Nerve Blocks for the On-Call Orthopaedic Surgeon

The on-call orthopaedic surgeon is faced with a wide array of orthopaedic pathology for which intra-articular aspiration, injection, and/or nerve/hematoma block may be used. Efficient use of these diagnostic and therapeutic modalities affords better patient care and a more effective on-call period. Often, these interventions are the rate limiting factor in a reduction or diagnosis. In this review, we describe joint aspirations, saline load tests, hematoma blocks, and nerve blocks in detail to include their indications, techniques, related pharmacology, pearls, and pitfalls.

Accuracy of Intraarticular Injections: Blind vs. Image Guided Techniques-A Review of Literature

Intra-articular injections are widely used for diagnostic and therapeutic purposes of joint pathologies throughout the body. These injections can be performed blind by utilizing anatomical landmarks or with the use of imaging modalities to directly visualize the joint space during injections. This review of the literature aims to comprehensively identify differences in the accuracy of intra-articular injections via palpation vs. image guidance in the most commonly injected joints in the upper and lower extremities. To our knowledge, there are no such comprehensive reviews available. A narrative literature review was performed using PubMed and Google Scholar databases to identify studies focusing on the accuracy of blind or image-guided intra-articular injections for each joint. A total of 75 articles was included in this review, with blind and image-guided strategies being discussed for the most commonly injected joints of the upper and lower extremities. Varying ranges of accuracy with blind and image-guided modalities were found throughout the literature, though an improvement in accuracy was seen in nearly all joints when using image guidance. Differences are pronounced, particularly in deep joints such as the hip or in the small joints such as those in the hand or foot. Image guidance is a useful adjunct for most intra-articular injections, if available. Though there is an increase in accuracy in nearly all joints, minor differences in accuracy seen in large, easily accessed joints, such as the knee, may not warrant image guidance.

Ultrasound-guided joint interventions of the lower extremity

The purpose of this article is to better understand the role ultrasound plays in lower extremity joint interventions. Ultrasound is an important and reliable tool diagnostically and therapeutically. Real-time feedback, lack of ionizing radiation, and dynamic maneuverability make ultrasound an important tool in the proceduralist's armament. This article will touch upon the important anatomic considerations, clinical indications, and technical step-by-step details for lower extremity ultrasound interventions. Specifically, we will look at interventions involving the hip, knee, ankle, and foot. In addition, this article will discuss the roles corticosteroid and platelet-rich plasma may play in certain interventions.

Comparing Accuracy of Wrist Intra-articular Needle Placement Via Ulnocarpal Approach by Training Level: A Cadaveric Study

Background

Intra-articular injections are a standard therapy and diagnostic tool for a variety of wrist conditions. Accurate needle placement is crucial for proper therapeutic benefit and prevention of complications. While some studies claim accurate needle placement requires imaging, others conclude that anatomical guidance is sufficient. This study aimed to evaluate the accuracy of intra-articular wrist needle placement with the ulnocarpal approach across differing levels of training using clinical anatomy alone.

Methods

Fourteen fresh-frozen, above-elbow cadaveric specimens were used. Intra-articular needle placement into the wrist via an ulnocarpal approach was attempted by nine study participants: two interns, two junior-level residents, two senior-level residents, two hand fellows, and one attending hand surgeon. Each injection was performed based on clinical examination and landmarks alone. The number of attempts and total time taken for each injection was recorded.

Results

Overall success rate was 71%, (89 of 126 attempts) and did not vary significantly across levels of training. Average time for needle placement among all participants was 10.9 ± 6.5 seconds. Timing of successful intra-articular needle placement (10.4 ± 5.2 seconds) significantly differed between levels. However, timing did not trend in any direction with more or less training. No significant difference was noted in total attempts or attempts with successful outcomes when comparing level of training.

Conclusion

The ulnocarpal approach is a viable option for injection or aspiration of the wrist without image guidance. We were unable to show any relevant trends with timing or number of attempts in comparison to level of training. Level of Evidence: V.

Reprogrammed Synovial Fluid-Derived Mesenchymal Stem/Stromal Cells Acquire Enhanced Therapeutic Potential for Articular Cartilage Repair

OBJECTIVES

Functions of mesenchymal stem/stromal cells (MSCs) are affected by patient-dependent factors such as age and health condition. To tackle this problem, we used the cellular reprogramming technique to epigenetically alter human MSCs derived from the synovial fluid of joints with osteoarthritis (OA) to explore the potential of reprogrammed MSCs for repairing articular cartilage.

MATERIALS AND METHODS

MSCs isolated from the synovial fluid of three patients' OA knees (Pa-MSCs) were reprogrammed through overexpression of pluripotency factors and then induced for differentiation to establish reprogrammed MSC (Re-MSC) lines. We compared the in vitro growth characteristics, chondrogenesis for articular cartilage chondrocytes, and immunomodulatory capacity. We also evaluated the capability of Re-MSCs to repair articular cartilage damage in an animal model with spontaneous OA.

RESULTS

Our results showed that Re-MSCs increased the in vitro proliferative capacity and improved chondrogenic differentiation toward articular cartilage-like chondrocyte phenotypes with increased THBS4 and SIX1 and decreased ALPL and COL10A1, compared to Pa-MSCs. In addition, Re-MSC-derived chondrocytes expressing elevated COL2A and COL2B were more mature than parental cell-derived ones. The enhancement in chondrogenesis of Re-MSC involves the upregulation of sonic hedgehog signaling. Moreover, Re-MSCs improved the repair of articular cartilage in an animal model of spontaneous OA.

CONCLUSIONS

Epigenetic reprogramming promotes MSCs harvested from OA patients to increase phenotypic characteristics and gain robust functions. In addition, Re-MSCs acquire an enhanced potential for articular cartilage repair. Our study here demonstrates that the reprogramming strategy provides a potential solution to the challenge of variation in MSC quality.

Osteoarthritis of the hip: are degenerative tears of the acetabular labrum predictable from features on hip radiographs?

BACKGROUND

A common feature of hip arthritis is the presence of labra tears. Recent literature suggests against the use of magnetic resonance imaging (MRI) in patients aged >45 years for the assessment of hip pain related to arthritis.

PURPOSE

To determine if radiographic features of osteoarthritis detectable on routine hip radiographs are accurate and reliable surrogate markers of degenerative acetabular labral tears identified on MR arthrography (MRA) and corroborated during arthroscopy.

MATERIAL AND METHODS

A retrospective study involving 86 symptomatic patients (hip pain) with radiologic work-up included MRA and pelvic or hip radiographs that underwent hip arthroscopy within three months. Imaging characteristics assessed on hip radiographs include measurements of superior acetabular, femoral head osteophyte, cortical thickness of the femoral shaft, and minimum joint space as well as presence of subchondral sclerosis of the femoral head and acetabulum, femoral shaft buttressing, and grade of arthritis. Presence of a labral tear was determined by consensus between three readers as well as by surgical correlation. The Pearson's chi-squared and Fisher's exact tests were used to compare presence of labral tears with each radiographic feature.

RESULTS

Seventy-one patients (82.6%) had labral tears: 49 (69%) women and 22 (31%) men. Receiver operating characteristic analysis showed statistical significance (P<0.05) between presence of a labral tear and acetabular and femoral head osteophyte sizes but failed to demonstrate any significance regarding acetabular subchondral sclerosis, cortical thickness, buttressing, or minimum joint space.

CONCLUSIONS

Radiographic markers such as the acetabular and femoral head osteophyte sizes demonstrated statistical significance with the presence of labral tears.

The PRECISION Survey: Preferences of Physicians Regarding Ultrasound-Guided Intra-Articular Injections

OBJECTIVE

The objectives of this survey study were to: (1) determine practice patterns, (2) assess beliefs and attitudes toward ultrasound-guided intra-articular injections (UGIIs), (3) identify barriers to the use of UGII, and (4) determine any differences in beliefs and attitudes based on age or specialty.

METHODS

A survey was developed using a focus group including physicians who perform intra-articular injections of the knee, shoulder, and/or hip. After validation by the focus group, the final survey (28 questions) was e-mailed to members of the Canadian Academy of Sport and Exercise Medicine (N = 632).

RESULTS

A total of 168 responses were received (26.6%). Nearly half of respondents rarely/never had access to UGII equipment (48.5%), and over half did not have adequate training in UGIIs (56.8%-68.8%). About half of respondents agreed that UGII improves accuracy in knee injections (50.9%); only 35.4% agreed there was evidence to support UGII over non-ultrasound-guided intra-articular injections (NGIIs) of the knee. Physicians younger than 50 years were significantly more likely to use UGII for the knee and hip if they had better access to equipment (P < 0.0005 for both); they were more likely to use UGII for the knee if it was less time-consuming (P = 0.001).

CONCLUSIONS

The majority of respondents are not using UGII for the knee or shoulder. Physicians may overestimate their accuracy in performing NGIIs. The biggest barriers to UGII were identified as: (1) inadequate training; (2) lack of access to equipment; and (3) lack of time. Younger physicians seem more open to adopting UGII if barriers are addressed.

Pearls and pitfalls of fluoroscopic-guided foot and ankle injections: what the radiologist needs to know

OBJECTIVE

This article provides a comprehensive, joint-by-joint review of fluoroscopic-guided foot and ankle injections and emphasizes pre-procedural planning, relevant anatomy, appropriate technique, troubleshooting the difficult procedure, and the importance of communicating unexpected findings with the referring clinician. The interrogation of pain generators including variant ossicles, fractures, and post-surgical/traumatic findings is also described.

CONCLUSIONS

Even the most challenging foot and ankle injections may be successfully completed with a solid anatomical understanding and thoughtful approach.

[Advanced cartilage imaging for detection of cartilage injuries and osteochondral lesions]

BACKGROUND

Osteochondral defects represent a main risk factor for osteoarthritis of the ankle.

OBJECTIVES

The aim of this article is to provide an overview of current optimal clinical cartilage imaging techniques of the foot and ankle and to show typical osteochondral injuries on imaging.

MATERIALS AND METHODS

A thorough literature search was performed and was supported by personal experience.

RESULTS

Cartilage imaging of the foot and ankle remains challenging. However, advanced morphological and quantitative magnetic resonance (MR) imaging techniques may provide useful clinical information, for example, concerning cartilage repair surgery. Compared to MRI, MR arthrography (MR-A) and CT arthrography (CT-A) have higher sensitivity with respect to detection of osteochondral defects. Regarding smaller joints of the foot, mainly advanced osteoarthritic changes are detected on conventional radiography; only in rare cases, MR and CT imaging of these smaller joints is of relevance.

CONCLUSIONS

While at the smaller joints of the foot cartilage imaging only plays a minor role, at the ankle joint cross-sectional cartilage imaging using CT and MRI becomes more and more important for clinicians due to emerging therapeutic options, such as different osteochondral repair techniques.

Guided Intra-articular Corticosteroid Injections in the Midfoot

BACKGROUND

Intra-articular corticosteroid injections are used for both their therapeutic and diagnostic function. There is a paucity of literature investigating the efficacy of intra-articular corticosteroid injections into the midfoot. The aim of the study was to identify the efficacy of image guided intra-articular corticosteroid (Methylprednisolone) injections for midfoot osteoarthritis The null hypothesis of this study was there would be no benefit or increase of the Self-reported Foot and Ankle Score (SEFAS) from an intra-articular corticosteroid injection.

METHODS

SEFAS was collected at 4 and 12 months postinjection. A total of 37 consecutive patients who had 67 midfoot injections were recruited into the study over a 6-month period.

RESULTS

The mean SEFAS score preinjection was 17.0, at 4 months postinjection was 31.8 ( P < .001), and 12 months postinjection 21.3 ( P < .14). There was a statistically significant improvement in postinjection SEFAS ( P < .001) at 4 months. The null hypothesis of this study was rejected. Response to the injection was varied but patients with BMI less than 30 had a sustained ( P < .04) symptomatic improvement at 12 months when compared to the obese patients.

CONCLUSION

Our findings support the use of corticosteroid injections as a viable diagnostic and therapeutic option following failed conservative treatment options prior to operative intervention. The results at 4 months were statistically significant with an additional finding of a difference observed between obese and nonobese patients. This may have implications for further educating the patient in effective weight loss that may improve symptom relief from intra-articular injection.

LEVEL OF CLINICAL EVIDENCE

Level III, comparative study.

The posterolateral approach for fluoroscopy-guided tibiotalar joint injection

OBJECTIVE

To report a novel technique for tibiotalar joint injection that utilizes a posterolateral approach, including indications and technical considerations.

METHODS

The posterolateral approach for tibiotalar injection is similar to that used in posterior subtalar joint injections. Using this technique, the tibiotalar joint space is accessed by directing the needle anterosuperiorly beneath the fibula until the posterior aspect of the talar dome has been reached. A retrospective review was conducted of all posterolateral approach tibiotalar joint injections at our institution.

RESULTS

Eight patients underwent 12 technically successful therapeutic anesthetic/steroid tibiotalar joint injections using the posterolateral approach under fluoroscopic guidance. All eight patients had anterior predominant arthrosis with large osteophytes and tibiotalar joint space narrowing. The injections were well tolerated without evidence of complications.

CONCLUSION

Posterolateral tibiotalar joint injection offers an alternative to the more commonly used anterior approach, particularly in cases of severe anterior predominant arthrosis. An additional advantage of this technique is that the ankle stays in the same position between the initial planning of the needle trajectory and the visualization of contrast flowing into the joint.

Diagnostic Value of CT Arthrography for Evaluation of Osteochondral Lesions at the Ankle

Background. To retrospectively determine the diagnostic value of computed tomography arthrography (CTA) of the ankle in the evaluation of (osteo)chondral lesions in comparison to conventional magnetic resonance imaging (MRI) and intraoperative findings. Methods. A total of N = 79 patients had CTAs and MRI of the ankle; in 17/79 cases surgical reports with statements on cartilage integrity were available. Cartilage lesions and bony defects at talus and tibia were scored according to defect depth and size by two radiologists. Statistical analysis included sensitivity analyses and Cohen's kappa calculations. Results. On CTA, 41/79 and 31/79 patients had full thickness cartilage defects at the talus and at the tibia, respectively. MRI was able to detect 54% of these defects. For the detection of full thickness cartilage lesions, interobserver agreement was substantial (0.72 ± 0.05) for CTA and moderate (0.55 ± 0.07) for MRI. In surgical reports, 88–92% and 46–62% of full thickness defects detected by CTA and MRI were described. CTA findings changed the further clinical management in 15.4% of cases. Conclusions. As compared to conventional MRI, CTA improves detection and visualization of cartilage defects at the ankle and is a relevant tool for treatment decisions in unclear cases.

The clinical and radiological importance of extraarticular contrast material leakage into adjacent synovial compartments on ankle MR arthrography in patients with OCD and anterolateral impingement

PURPOSE

To evaluate the tibiotalar joint capacity and the localisation, frequency and amount of extravasation in patients with extraarticular contrast material leakage into adjacent synovial compartments on ankle magnetic resonance (MR) arthrography.

MATERIALS AND METHODS

Sites of extravasation were determined in the ankle MR arthrograms of 69 patients. Thirty-four patients without extraarticular contrast material leakage into locations unrelated to the injection path were included as a control group. Volumetric measurements of extraarticular contrast material leakage and the tibiotalar joint capacity were performed on a three dimensional (3D) volume measurement workstation.

RESULTS

Extravasation of contrast material occurred through the anterior, posterior, and anterolateral recesses of the tibiotalar joint. The most common site of extravasation was along the flexor hallucis longus tendon synovium (24.6%). The amount of extravasation was significantly higher in patients with ankle osteochondritis dissecans (OCD) than in patients with a different diagnosis (p=0.039). Loose bodies were detected in all OCD's patients with insufficient tibiotalar joint distention.

CONCLUSIONS

Connections between the ankle joint and neighboring synovial compartments can decrease the diagnostic value of ankle MR arthrography examinations due to inadequate joint distention. Large injection volumes should be used for ankle MR arthrography of patients with OCD (especially OCD's patients with loose body) and impingement syndrome.

Magnetic resonance arthrography and the prevalence of acetabular labral tears in patients 50 years of age and older

OBJECTIVE

Arthroscopy for acetabular labral tears has minimal impact on pain and function in older patients, especially in the setting of concomitant osteoarthritis. Still, many physicians seek this diagnosis with MR arthrography. Our purpose is to assess the frequency of acetabular labral tears in older patients with hip pain and correlate likelihood of labral pathology with severity of osteoarthritis as visualized on conventional radiograph.

MATERIALS AND METHODS

From 2004 to 2013, 208 hip MRI arthrograms and corresponding radiographs on patients aged 50 years and older were identified. Age, gender, grade and location of labral tear, alpha angle, Tönnis grade, and joint space width were documented. Labral tears and alpha angle were identified and measured on MR arthrogram. Tönnis grade and joint space width were measured on radiographs.

RESULTS AND CONCLUSIONS

On MR arthrography, true labral tearing was identified in 73 % of patients. There was some degree of labral pathology in 93.3 % of patients, and this increased to 100 % in patients with moderate to severe osteoarthritis, as defined by Tönnis grade 2-3 or joint space width ≤ 2 mm. There were no statistically significant correlations between labral tear grade and Tönnis grade or joint space width. Given the high frequency of labral pathology and the questionable efficacy of arthroscopic surgical intervention in older patients, MR arthrography should be primarily for those with minimal arthritis on radiograph and potential to benefit from surgery. If further imaging beyond radiographs is necessary in these patients, standard MRI may be a more appropriate imaging tool.

Anatomic Landmarks of the Distal Radioulnar Joint

HYPOTHESIS

Using Lister's tubercle and the ulnar styloid as landmarks, accurate localization of the distal radioulnar joint can be achieved without the need for an image-guided approach.

METHODS

Cadaveric dissection of 16 upper extremities was performed to measure the relationships between the ulnar styloid, Lister's tubercle, and the distal radioulnar joint. In each specimen, the location of the distal radioulnar joint (point A) in relation to Lister's tubercle and the ulnar styloid was determined as follows: (1) the perpendicular distance between the distal radioulnar joint and ulnar styloid-Lister's tubercle was measured; (2) with A' marking the intersection of this distance and the ulnar styloid-Lister's tubercle line, the location of the distal radioulnar joint along the ulnar styloid-Lister's tubercle axis was determined by comparing ulnar styloid-A' and A'-Lister's tubercle with ulnar styloid-Lister's tubercle.

RESULTS

The mean distance between ulnar styloid-Lister's tubercle was 4.3 ± 0.4 cm. The mean perpendicular distance between the distal radioulnar joint and the ulnar styloid-Lister's tubercle line was 0.2 ± 0.1 cm proximal to the ulnar styloid-Lister's tubercle line. The ratio of ulnar styloid-A' and A'-Lister's tubercle to ulnar styloid-Lister's tubercle was 0.5 ± 0.03 and 0.5 ± 0.03, respectively.

CONCLUSIONS

Simple relationships between the ulnar styloid and Lister's tubercle serve as reliable landmarks for locating the distal radioulnar joint. The distal radioulnar joint is centered about the midpoint of the ulnar styloid-Lister's tubercle axis and slightly proximal to it. This may improve the accuracy and efficacy of corticosteroid injections in the treatment of distal radioulnar joint arthritis without the need for image guidance.

Groin pain in athletes: a novel diagnostic approach

Groin pain in a performing athlete can be very challenging to diagnose and treat. The differential diagnosis includes intra-articular causes, extra-articular causes and non-musculoskeletal causes. A detailed clinical and radiological assessment of groin pain in this group is critical and can identify the underlying pathology. Diagnostic hip block is a valuable tool to differentiate intra-articular causes from extra-articular causes. Hip arthroscopy can help in identifying some of the elusive intra-articular conditions, which were once undiagnosed and therefore, left untreated, resulting in premature ending of competitive careers. This article attempts to explore current thinking on evaluation of groin pain, particularly in young individuals, and to establish a simple protocol for a clinical and diagnostic approach to this difficult problem.

Pulse-dose radiofrequency can reduce chronic pain in trapezio-metacarpal osteoarthritis: A mini-invasive therapeutic approach

AIM

To assess the efficiency of pulse-dose radiofrequency (PDRF) in the management of chronic pain in patients with trapezio-metacarpal osteoarthritis (OA).

METHODS

Seventy-five patients with trapezio-metacarpal OA were treated with the PDRF between October 2011 and September 2013. A 22-gauge cannula with a 5-cm length was introduced with percutaneous access in the lateral region of the affected trapezio-metacarpal joint. The PDRF procedure was performed with 1200 pulses at 45 V and 20 msec duration, followed by a 480 msec silent phase. The follow-up visits were performed at 1 month, 3 and 6 months after the PDRF procedure. All patients underwent a second treatment between 7 and 9 months after the first PDRF procedure with a new follow-up scheme at 1, 3, 6 and 9 months.

RESULTS

Mean visual analogue scale (VAS) scores before the procedures was 8.5 ± 1.1. A great reduction in pain intensity was reported at 3 months after the PDRF procedure (mean VAS scores 3.1 ± 0.9, P < 0.05). Pain intensity began to increase back to pre-procedural values after 4 months (mean VAS scores at 6 months was 7.9 ± 1.3, P < 0.05). After the second PDRF treatment the mean VAS scores decreased to 3.3 ± 0.8 at 3 months, but increased to 8.1 ± 1.6 at 9 months. (P < 0.05). No complications after the procedures were observed.

CONCLUSIONS

The PDRF may be a safe, repeatable and effective short-term pain management technique in patients with trapezio-metacarpal OA. Larger, randomized controlled studies are indicated to better clarify the efficacy and utility of the PDRF.

Ultrasound-guided joint injections for MR arthrography in pediatric patients: how we do it

In children, MR arthrography is typically performed using fluoroscopic guidance. This article explores the role of US-guided joint injections as an alternative for MR arthrography in children, discussing its advantages and disadvantages compared to standard methods. We describe techniques for performing US-guided injection of the shoulder, elbow, hip, knee, ankle and posterior subtalar joints, highlighting pertinent anatomy, routes of access and unique considerations for this modality in children. Written descriptions, images and links to video clips are used to illustrate proper arthrographic technique. We conclude that US provides effective guidance for intra-articular injection prior to MR arthrography, with the advantages of improved visualization of internal structures, reduced radiation exposure, convenience of performing the procedure portably and ease of performance. Although this paper does not address therapeutic steroid injections, these techniques could easily be translated for such purposes. We propose US guidance as a viable alternative to fluoroscopic technique for arthrography in children.

A motive for the use of a posterior approach in shoulder arthography: ventral leakage of contrast medium

BACKGROUND

Some orthopedic surgeons request a posterior approach for shoulder magnetic resonance (MR) arthrography, especially in patients with anterior shoulder instability, to avoid interpretive difficulties in differentiating anterior extraarticular contrast injection when using an anterior approach from ventral leakage of contrast.

PURPOSE

To determine the occurrence of ventral leakage of contrast in shoulder MR arthrography when using a posterior approach.

MATERIAL AND METHODS

Retrospectively, we included 73 consecutive patients who underwent shoulder MR arthrography (1.0 Tesla) using the posterior approach. Three unsuccessful procedures were excluded. Ventral leakage of contrast, defined as contrast seen around the musculus subscapularis without distention of the posterior capsule, was recorded. Descriptive statistics were used.

RESULTS

Seventy shoulders were included. Forty-one left shoulders were involved (59%). Mean age of patients was 49 years (range, 17-76 years). Thirty-five patients were women (50%). Ventral leakage of contrast was seen in 12 shoulders (17%).

CONCLUSION

As ventral leakage of contrast was seen in a substantial number of cases when using a posterior approach in shoulder MR arthrography, the use of a posterior approach is advised to avoid misinterpretation of ventral contrast leakage with accidental extra articular contrast injection, and to increase confidence in the final radiological diagnosis.

Value of ultrasound before joint aspiration

OBJECTIVE

The purpose of this article is to illustrate and discuss the value of ultra-sound screening before joint aspiration.

CONCLUSION

Before joint aspiration, ultrasound assessment of the overlying and surrounding soft tissues requires little time and is relatively inexpensive. Bursal fluid collections, soft-tissue abscesses, and other fluid collections that would be undetected with fluoroscopy or blind aspiration can thus be identified. Ultrasound screening before joint aspiration can aid diagnosis and decrease the risk of iatrogenic complications.

Musculoskeletal aspiration procedures

With advances in imaging technology, there has been a significant increase in the number and range of interventional musculoskeletal image-guided procedures. One of the most commonly performed image-guided musculoskeletal interventions is the diagnostic and therapeutic percutaneous aspiration and drainage of multiple types of intra-articular, juxta-articular, and intramuscular pathologic fluid collections. These procedures may be performed under fluoroscopic, ultrasound, computed tomography, or even magnetic resonance guidance depending on the location to be accessed, type of pathology, patient characteristics, and operator preference. Musculoskeletal image-guided aspiration and drainage procedures are minimally invasive and generally very safe while offering valuable diagnostic information as well as therapeutic benefit. This article focuses on the appropriate indications, contraindications, and general technique for accessing the major joints via imaging guidance. For each joint, we discuss pertinent anatomy, appropriate imaging modalities, and preferred approaches to gaining intra-articular access. Additionally, the article discusses some of the more frequently encountered juxta-articular and intramuscular fluid collections that can be accessed and aspirated via percutaneous intervention, with mention of the importance of recognizing extremity sarcomas that can mimic these benign collections.

A positive hip arthrogram may predict lower function in patients with primary hip arthroplasty

BACKGROUND

A local anesthetic hip arthrogram is a simple test mainly used as an adjunct to define the origin of hip pain. Temporary pain relief (a positive response) following an injection may lead to a surgeon recommending hip surgery. However, it is unclear whether relief of pain corresponds to better postoperative pain relief or function.

QUESTIONS/PURPOSES

We therefore compared the function in patients with a positive response to a local anesthetic hip arthrogram who underwent primary THA and patients with typical osteoarthritis presentation who underwent primary THA without a preoperative arthrogram.

METHODS

We retrospectively reviewed 22 patients who had a positive response to a local anesthetic hip arthrogram who subsequently underwent primary hip arthroplasty and a control group of 74 patients who had typical osteoarthritis hip pain and subsequent primary hip arthroplasty without having a previous arthrogram. All patients completed the Oxford Hip Score, WOMAC™ function short form, and the SF-12 preoperatively and at regular clinical followups. The minimum followups were 28 months (mean, 42 months; range, 28-72 months) for the study group and 33 months (mean, 52 months; range, 33-73 months) for the control group.

RESULTS

Patients in the arthrogram group had lower mean functional scores: 30 versus 39 for the Oxford Hip Score, 39 versus 46 for the WOMAC™, and 36 versus 42 for the physical component of the SF-12.

CONCLUSIONS

Preoperative use of a local anesthetic hip arthrogram remains an important tool to differentiate spinal disorders or confirm the hip as the cause of pain. However, patients who have a preoperative hip arthrogram to clarify symptoms may report a lower function score and pain relief than patients who do not.

Magnetic resonance-guided interventions of large and small joints

Magnetic resonance (MR)-guided interventions of large and small joints are feasible and safe procedures offering several advantages compared with standard guiding techniques. Nevertheless, MR-guided interventions are not routinely performed in daily practice apart from a few centers. Accurate injections are crucial for clinical outcome in diagnostic arthrography as well as therapeutic joint injections. In particular, palpatory joint puncture was shown to be inaccurate or uncertain in a substantial percentage of injections of the shoulder, the hip, and the knee. Magnetic resonance imaging offers respective merits of a cross-sectional technique with high soft-tissue contrast. Exact depiction of structures, which should be preserved, such as the labrum, should be aimed for. Areas with complex anatomy can be approached by adapting the right imaging plane(s) because of multiplanar capacity. Lack of ionizing radiation for patients is of growing interest particularly in young patients with repeated interventions. Magnetic resonance guidance alone allows an "all-in-one" MR arthrography combining precise targeting with high-field-strength imaging. Modern short-bore and open-bore high-field-strength systems offer a good comfort for patients as well as clinicians and enhance patient positioning options such as supine or prone position. Thus, a tailored approach such as a posterior technique for suspected anterior lesions in shoulder MR arthrography is possible.In this article, we describe the advantages and limitations of MR guidance in joint interventions with focus on shoulder and hip interventions. We review the requirements for needle material and MR sequences, discuss several different techniques developed to date, and present current results in clinical outcome.