US of the anterior bundle of the ulnar collateral ligament: findings in five cadaver elbows with MR arthrographic and anatomic comparison--initial observations

Shoulder and Elbow Injuries in Adult Overhead Throwers: Imaging Review

Overhead throwing, particularly in baseball, subjects the shoulder and elbow to various unique injuries. Capsular contracture following repetitive external rotation shifts the humeral head posterosuperiorly, predisposing to glenohumeral internal rotation deficit (GIRD), Bennett, posterosuperior internal impingement (PSI), and superior labrum anterior-posterior (SLAP) lesions. GIRD represents loss of internal rotation at the expense of external rotation. Bennett lesion represents ossification of the posteroinferior glenohumeral ligament due to repetitive traction. PSI manifests with humeral head cysts and "kissing" tears of the posterosuperior cuff and labrum. Scapular dysfunction contributes to symptoms of PSI and predisposes to labral or rotator cuff disease. "Peel-back" or SLAP lesions occur when torsional forces detach the biceps-labral anchor from the glenoid. Finally, disorders of the anterior capsule, latissimus dorsi, teres major, and subscapularis are well recognized in overhead throwers. At the elbow, injuries typically involve the medial-sided structures. The ulnar collateral ligament (UCL) is the primary static restraint to valgus stress and can be thickened, attenuated, ossified, and/or partially or completely torn. Medial epicondylitis can occur with tendinosis, partial tear, or complete rupture of the flexor-pronator mass and can accompany UCL tears and ulnar neuropathy. Posteromedial impingement (PMI) and valgus extension overload syndrome are related entities that follow abundant valgus forces during late cocking or acceleration, and deceleration. These valgus stresses wedge the olecranon into the olecranon fossa, leading to PMI, osteophytes, and intra-articular bodies. Other osseous manifestations include olecranon stress fracture and cortical thickening of the humeral shaft. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Reliability of sonographic measurements of the ulnar collateral ligament: a multi-rater prospective study

Background

The use of sonography is a cost-effective and reliable method to evaluate upper extremity superficial tissue structural integrity and pathology. Establishing the measurement reliability of widely used diagnostic ultrasound evaluation for musculoskeletal assessment is paramount enhance accurate clinical evaluations. The objective of this study was to establish the inter-rater and intra-rater reliability of select ulnar collateral ligament (UCL) thickness measures at two distinct anatomical locations in intercollegiate baseball athletes using ultrasound imaging (USI).

Methods

This was a prospective cohort study conducted in a university research laboratory and included a total of 17 NCAA Division I baseball athletes (age 20.4 ± 1.43, height = 183.63 cm ± 6.27 cm, mass = 89.28 kg ± 8.24 kg). Two trained clinicians measured UCL mid-substance and apex thickness in the throwing extremity, prospectively, on 5 occasions at 1-month intervals during rest. Intraclass correlation coefficients (ICCs) (model 3,3), associated standard error of measurement, and 95% minimal detectable change in thickness were derived.

Results

Intrarater reliability estimates for operator 1 were 0.90-0.98 (mid-substance) and 0.91-0.99 (apex). Operator 2's values were 0.92-0.97 and 0.93-0.99, respectively. The standard error of measurement (SEM) ranged from 0.045-0.071 cm (mid-substance) and 0.023-0.067 cm (apex). The minimal detectable difference (MDD95) was 0.12-0.20 cm (mid-substance) and 0.07-0.19 cm (apex). Interrater reliability was 0.86-0.96 (mid-substance) and 0.79-0.98 (apex); most ICCs were >0.90. Measurement of UCL thickness at two locations demonstrated very good to excellent reliability with high precision. Using this protocol, two evaluators can obtain consistent UCL measurement at two positions. This finding has significant implications for the clinical evaluation of superficial tissue pathology of the same individual by two experienced practitioners.

Sonographic morphological and qualitative deficits in the elbow ulnar collateral ligament and ulnohumeral joint in throwing arms of asymptomatic collegiate baseball pitchers

OBJECTIVE

The ulnar collateral ligament (UCL) supports the medial elbow against valgus torque and is commonly injured in baseball pitchers. Changes in UCL morphology and pathology occur with long-term pitching, with more severe findings at higher competition levels. We examined the bilateral differences and the relationship between UCL morphology, pathology, and ulnohumeral joint laxity in asymptomatic collegiate pitchers using ultrasound.

MATERIALS AND METHODS

Division I college pitchers (n = 41) underwent ultrasound scans of their bilateral medial elbows, both at rest and in a valgus-stressed position. The presence of enthesopathy, calcifications, and degeneration was assessed qualitatively. UCL thickness and ulnohumeral joint gap were measured with online calipers. The bilateral differences were analyzed using paired t-tests and chi-square analysis, and the relationships between thickness, gapping, and degenerative changes were analyzed using regression analyses.

RESULTS

The throwing arm demonstrated greater distal UCL thickness (mean difference (MD) = 0.2 mm (95%CI = 0.1-0.3), p < 0.01), resting and stressed gap (MD = 0.3 mm (95%CI = 0.0-0.7), p = 0.04; MD = 0.4 (95%CI = 0.0-0.9), p = 0.02), and greater prevalence of degeneration and enthesopathy (p = 0.03) compared bilaterally. Enthesopathy and calcifications predicted increased distal UCL thickness (p = 0.04; p = 0.02). Degenerative scores predicted increased stressed-resting ulnohumeral joint gap (p < 0.01).

CONCLUSION

In the throwing arms of collegiate pitchers, ultrasound demonstrated UCL thickening, enthesopathy/intra-ligamentous calcification, and greater laxity of the ulnohumeral joint relative to the non-throwing arm. Degeneration of the UCL, not thickness, was related to greater elbow joint gapping. This study demonstrates the utility of ultrasound for examining sonographic characteristics of the UCL in a sample of college pitchers.

The Role of Ultrasound in the Evaluation of Elbow Medial Ulnar Collateral Ligament Injuries in Throwing Athletes

PURPOSE OF REVIEW

Although ultrasound (US) imaging is commonly used to evaluate the elbow medial ulnar collateral ligament (mUCL) in throwing athletes, significant technical heterogeneity exists in the published literature and in practice. This has resulted in variable and often ambiguous US diagnostic criteria for mUCL injury. This review summarizes the literature on sonographic evaluation of the mUCL and outlines recommendations for consistent descriptive terminology, as well as future clinical and research applications.

RECENT FINDINGS

Both acute and chronic throwing loads in overhead athletes cause the mUCL to become thicker and more lax on stress testing, and these changes tend to revert after a period of prolonged rest. Stress US (SUS) can aid in the diagnosis of mUCL tears and may help identify athletes at risk of mUCL injury. Variability exists in terminology, elbow flexion angle, amount of stress applied, and technique of stress testing. Recent studies have suggested an injured elbow stress delta (SD-change in ulnohumeral joint (UHJ) space with valgus stress) of 2.4 mm and a stress delta difference (SDD-side-side difference in SD) of 1 mm each denote abnormal UHJ laxity due to mUCL injury. US imaging is a powerful and widely accessible tool in the evaluation elbow mUCL injuries. Sonologists should consider how their US techniques compare with published methods and use caution when applying diagnostic criteria outside of those circumstances. Currently, an SD of 2.4 mm and an SDD of 1 mm provide the best diagnostic accuracy for mUCL tears requiring surgery. Finally, preliminary work suggests that shear wave elastography may be helpful in evaluating the biomechanical properties of the mUCL, but additional research is needed.

Acute Ligament Injuries of the Elbow

Ulnar collateral, radial collateral, lateral ulnar collateral, and annular ligaments can be injured in an acute trauma, such as valgus stress in athletes and elbow dislocation. Recognizing normal anatomy in magnetic resonance imaging and ultrasonography studies is important to identify ligamentous abnormalities in these imaging modalities.

Practical ultrasonographic technique to precisely identify and differentiate tendons and ligaments of the elbow at the level of the humeral epicondyles: anatomical study

OBJECTIVES

To develop a practical step-by-step technique to precisely identify and differentiate tendons and ligaments attaching to the humeral epicondyles, to confirm through gross anatomical study the accurate structure identification provided by this technique and to determine the frequency at which each structure can be identified in healthy volunteers.

MATERIALS AND METHODS

First, ten fresh frozen cadavers (6 men, age at death = 58-92 years) were examined by two musculoskeletal radiologists and a step-by-step technique for the identification of tendons and ligaments at the level of humeral epicondyles was developed. Second, the accurate identification of structures was confirmed through gross anatomical study including anatomical sections on five specimens and layer-by-layer dissection technique on five others. Finally, 12 healthy volunteers (6 men, average age = 36, range = 28-52) were scanned by two radiologists following the same technique.

RESULTS

An ultrasonographic technique based on the recognition of bony landmarks and the use of ultrasonographic signs to differentiate overlapping structures was developed and validated through gross anatomical study. In healthy volunteers, most tendons and ligaments were identified and well-defined in ≥ 80% of cases, except for the extensor carpi radialis brevis and extensor digiti minimi tendons on the lateral epicondyle (having common attachments with the extensor digitorum communis) and the palmaris longus tendon on the medial epicondyle (absent, or common attachment with the flexor carpi radialis).

CONCLUSION

A step-by-step approach to the ultrasonographic assessment of tendons and ligaments at the humeral epicondyles allowed accurate identification of and differentiation among these structures, in particular those relevant to pathological conditions.

Back to the roots of rheumatology - Imaging of regional pain syndromes

Musculoskeletal regional pain syndromes (RPS) often lead to patient referrals in general and rheumatological practice. Detailed history taking and clinical examination can, in most cases, reveal the cause for pain and direct the subsequent management of the conditions. Yet, when in doubt, imaging methods, such as ultrasound (US) may support the clinical assessment. This paper reviews the underlying pathologies of some of the most frequently encountered RPS and the role of musculoskeletal US imaging for their diagnosis and treatment. If available, data on diagnostic accuracy and comparisons with gold standards are reported. The article stresses the importance of anatomical and sonoanatomical knowledge for the proper interpretation of the US images, points out the advantages and disadvantages of this imaging tool, and suggests the future research agenda.

Ultrasonographic Technique, Appearance, and Diagnostic Accuracy for Common Elbow Sports Injuries

Ultrasonography is a valuable diagnostic imaging tool because of its availability, tolerability, low cost, and utility in real-time dynamic evaluation. Its use in diagnosing elbow injuries has expanded recently and continues to do so. In particular, stress ultrasonography represents a unique imaging technique that directly visualizes the ulnar collateral ligament (UCL) and allows the assessment of ligament laxity, offering an advantage over magnetic resonance imaging and magnetic resonance arthrography in this patient population. Furthermore, ultrasonography has shown particular usefulness in instances where invasive techniques might be less desirable. This is particularly important in athletes since more invasive procedures potentially result in lost time from their sport. Ultrasonography is an important imaging tool that complements a thorough history and physical examination in the evaluation of elbow injuries in athletes. The use of ultrasonography in orthopaedic sports medicine has been investigated previously; however, to our knowledge, there has been no comprehensive review regarding the utility of ultrasonography for common elbow injuries in athletes. The current study provides a comprehensive, detailed review of the utility and indications for the use of ultrasonography for common elbow injuries in athletes.

Correlation of MRI to Arthroscopy in the Elbow: Thrower's Elbow and Ulnar Collateral Ligament Injury

One cannot overstate the importance of a thorough history and physical examination, supplemented with directed imaging, to help pinpoint the exact cause of the athlete's elbow pain. Although plain radiographs should not be overlooked, advanced imaging plays a critical role in diagnosis and management of pathology in the thrower's elbow, including computed tomography, magnetic resonance imaging, and stress ultrasound. By judiciously combining these elements, the clinician can appropriately manage these injuries in order to successfully return the athlete to their preinjury level of play.

Anterior and posterior bands of the anterior bundle in the elbow ulnar collateral ligament: ultrasound anatomy

BACKGROUND

The anterior oblique bundle (AOL) of the ulnar collateral ligament (UCL) is composed of anterior and posterior bands. This study evaluated the anatomy of the anterior and posterior bands in the AOL of the UCL for their separate visualization with ultrasound (US).

METHODS

We dissected 18 cadaveric elbow joints and recorded the direction of each band from the lateral view to determine the proper position for the US transducer. To determine the proper inclination of the transducer, we measured the inclinations of each band at the proximal and distal insertions from the transverse view. A paired t test was used for comparisons between both bands. Values of P < .05 were considered statistically significant.

RESULTS

The mean angles of the directions in the anterior and posterior bands were 10° ± 4° and 24° ± 9°, respectively. At the medial epicondyle, the mean inclination angles of both bands were 61° ± 5° and 67° ± 5°, respectively. At the sublime tubercle, the mean inclination angles of both bands were 14° ± 7° and 44° ± 9°, respectively. The inclination angles at the proximal ulna and the directions in both bands were significantly different (P < .001).

CONCLUSIONS

This study shows that the directions of both bands and inclination angles of the bony attachments in both bands can assist with correct placement of the US transducer and allow for separate visualization of each band.

Ultrasound evaluation of the ulnar collateral ligament of the elbow: Which method is most reproducible?

INTRODUCTION

The ulnar collateral ligament (UCL) is an important medial stabilizer of the elbow, particularly in overhead-throwing athletes. However, there is no universally accepted method for evaluating UCL thickness with ultrasound (US).

OBJECTIVE

To assess reproducibility of previously published methods, as well as a modified technique, for evaluating the UCL via US. We hypothesize that a modified technique would show greater reproducibility.

MATERIAL AND METHODS

Using US, the thickness of the UCL in 50 volunteers was measured by two musculoskeletal trained radiologists using two different measurement techniques. The techniques utilized were as described by Nazarian and Jacobson/Ward (JW). Technique measurements were evaluated using interclass correlation coefficients (ICC) to determine the reproducibility of each method. Twenty-eight of the subjects also underwent measurement via a modified JW technique, measured perpendicular to the ligament rather than the frame of imaging. This technique was also evaluated with ICC values.

RESULTS

The ICC value for the Nazarian technique was 0.82 (very good) and 0.51 (moderate) for the JW technique. When using the modified JW technique, we found an ICC value of 0.84 (very good). Mean ligament thickness was greatest with the Nazarian technique, 6.41 mm, with the JW technique measuring 1.86 mm and the modified technique measuring 1.38 mm.

CONCLUSION

US assessment of UCL thickness by all three measurement techniques are reproducible. The JW technique had less interobserver agreement when compared to the Nazarian method, whereas the modified JW technique had greater reproducibility compared to the JW technique and similar to the Nazarian technique.

Stress ultrasound in baseball players with ulnar collateral ligament injuries: additional value for predicting rehabilitation outcome

BACKGROUND

The purpose of this study was to evaluate the additional value of stress ultrasound (US) for predicting rehabilitation outcome in baseball players with ulnar collateral ligament (UCL) injury.

METHODS

Stress US and magnetic resonance imaging (MRI) in 41 baseball players with UCL injury who received rehabilitation treatment for more than 6 weeks were retrospectively compared between the rehabilitation group (n = 23) and surgery group (n = 18). The MRI grade of UCL injury was assessed as intact continuity, low-grade partial tear, high-grade partial tear, and complete tear. To estimate sonographic joint laxity, we assessed 3 sonographic criteria as present or absent: ligamentous waviness, joint gapping, and intra-articular ring-down artifact. In addition, the presence of concomitant tenderness was checked during stress US. The diagnostic validity of MRI with and without stress US was analyzed as a predictor for the rehabilitation outcome.

RESULTS

The MRI grade was higher in the surgery group than in the rehabilitation group (P < .001). Sonographic joint laxity showing the ring-down artifact and concomitant tenderness with stress were significantly more frequent in the surgery group (P = .024 and P = .006, respectively). Sensitivity, specificity, and accuracy were 61.1%, 86.9%, and 75.6%, respectively, for MRI alone and 83.3%, 56.5%, and 68.2%, respectively, for the combination of MRI with joint laxity showing the ring-down artifact. For MRI in combination with joint laxity and concomitant tenderness, these values were 72.2%, 82.6%, and 78.0%, respectively.

CONCLUSION

The addition of stress US showing the ring-down artifact and concomitant tenderness was helpful for predicting the rehabilitation outcome of UCL injuries.

Ultrasound Imaging of Ulnar Collateral Ligament Injury

The patient was an 18-year-old collegiate baseball pitcher who injured his right throwing elbow during an overhead slider pitch. As a part of a study, preinjury ultrasound images of the throwing arm were obtained 2 weeks prior to the injury. One day postinjury, repeat ultrasound imaging of the medial elbow was performed. The attending team physician ordered a magnetic resonance arthrogram 2 days after injury, which confirmed the presence of a complete tear of the ulnar collateral ligament. J Orthop Sports Phys Ther 2016;46(12):1086. doi:10.2519/jospt.2016.0420.

The morphologic change of the ulnar collateral ligament of elbow in high school baseball pitchers, with and without symptoms, by sonography

BACKGROUND

Few reports in the literature relate morphologic changes of the ulnar collateral ligament (UCL) to prior elbow symptoms. This study used ultrasonography (US) to assess the ulnohumeral joint space width, with and without stress, and elucidate morphologic changes of the UCL of the elbow in high school pitchers with and without a history of elbow symptoms.

METHODS

Each of 122 high school baseball pitchers who underwent US of the medial aspect of both elbows completed a self-administered questionnaire related to the self-satisfaction score (0-100) for pitching performance and throwing-related elbow joint pain sustained during the prior 3 years. We conducted gravity stress US elbow examination with 30° of flexion with and without valgus stress. Comparisons of the UCL thickness and ulnohumeral joint space width, with and without valgus stress, were made among the 122 high school pitchers with and without a history of elbow symptoms.

RESULTS

Pitchers with an elbow symptom history exhibited a greater difference between the UCL thickness on the throwing side than those with no elbow symptom history (P = .0013). A negative significant association was found between UCL thickness on the pitching side and the self-evaluation score for pitching performance (r = -0.20, P = .04).

CONCLUSIONS

US assessment demonstrated that the UCL in the dominant side with elbow symptom history was thicker than that with no elbow symptom history. The UCL thickness might reflect the prior pitching condition of high school baseball pitchers.

Optimal Elbow Angle for Sonographic Visualization of the Ulnar Collateral Ligament

OBJECTIVE

To formally examine the sonographic appearance of the elbow ulnar collateral ligament (UCL) at 30° versus 70° of elbow flexion in asymptomatic baseball pitchers.

DESIGN

A prospective, cross-sectional design.

SETTING

Sports medicine clinic in a tertiary academic medical center.

PARTICIPANTS

Thirty asymptomatic adolescent baseball pitchers 13-18 years of age (mean 15.8 years), with at least 3 years of continuous pitching experience and no significant history of elbow pain or injury.

METHODS

Static sonographic images of the bilateral UCLs were obtained at 30° and 70° of elbow flexion by a single experienced examiner. Images were anonymized and randomized into a slide set. Three clinicians with different levels of ultrasound experience reviewed the static 30° and 70° images for each elbow and chose their preferred image based on UCL conspicuity. The clinicians reviewed a re-randomized slide set 1 week later. A different study co-investigator measured UCL cross-sectional area (CSA) on all images using ultrasound machine electronic calipers.

MAIN OUTCOME MEASURES

Preference for the sonographic conspicuity of the UCL at 30° versus 70° of elbow flexion, and UCL CSA at 30° versus 70° of flexion.

RESULTS

Each clinician demonstrated a significant preference for UCL images obtained at 70° of flexion when compared to those obtained at 30° (80.3% overall preference for 70°, P < .001). There was no statistically significant effect of clinician experience or arm dominance on image preference. The sonographically determined CSA of the UCLs were on average 1.4 mm(2) greater at 70° than at 30° of flexion (P < .001) when combining dominant and nondominant arms.

CONCLUSIONS

Static sonographic evaluation of the UCL at 70° of elbow flexion should be integrated into UCL imaging protocols. Furthermore, when performing sonographically guided procedures targeting the UCL, clinicians should consider positioning the elbow at >30° of flexion to optimize UCL conspicuity and CSA.

A sonographic technique to evaluate the anterior bundle of the ulnar collateral ligament of the elbow: imaging features and anatomic correlation

OBJECTIVES

The aim of this study was to test a sonographic technique used to view the anterior bundle of the ulnar collateral ligament (UCL), describe its sonographic characteristics in healthy volunteers, and verify these characteristics by determining interobserver variability and their correlations in cadavers.

METHODS

Sonographic studies of the anterior bundle of the UCL were performed on 48 elbows of asymptomatic healthy volunteers. The participants were examined by 3 experts, who identified the insertion sites of the anterior bundle and subjectively evaluated its echogenicity and echo texture. A sonographic examination of the anterior bundle of the UCL in a cadaveric elbow was performed, and the same aspects were evaluated.

RESULTS

In all cases, the anterior bundle of the UCL appeared as a triangular structure in the coronal plane and had a hyperechoic homogeneous echo texture in most of these cases. The cadaveric elbow had the same sonographic characteristics as the volunteers.

CONCLUSIONS

As shown by examining the interobserver variability and determining the correlation with cadaveric tissue, sonography proved to be a reliable tool for evaluating the normal aspects of the anterior bundle of the UCL.

Stress ultrasound evaluation of medial elbow instability in a cadaveric model

BACKGROUND

An injury of the ulnar collateral ligament (UCL) is potentially career threatening for elite overhead-throwing athletes. Stress ultrasonography (SUS) allows for a rapid, cost-effective, and noninvasive evaluation of the UCL and elbow joint both at rest and with applied stress.

PURPOSE/HYPOTHESIS

To determine the amount of cadaveric elbow valgus gapping with sequential sectioning of medial elbow structures as measured by SUS. It was hypothesized that the greatest increase in ulnohumeral joint gapping would be noted with release of the anterior bundle of the UCL.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Twelve cadaveric elbows were divided into 2 groups and dissected in reverse sequences under the direct supervision of an experienced orthopaedic surgeon. Baseline ultrasound and SUS with applied valgus loads were performed by an experienced radiologist. A valgus load was applied at each sectioning interval using a standardized device. Ulnohumeral joint gapping in millimeters was measured by SUS for each step as the width of the medial joint from the trochlea to the sublime tubercle. The mean increases in joint gapping (Δ) between each step were calculated to quantify the additional gapping achieved with release of each sequential stabilizer.

RESULTS

Release of the anterior band of the anterior bundle resulted in a mean Δ of 2.0 mm (95% CI, 1.1-2.8 mm). Release of the posterior band of the anterior bundle resulted in a mean Δ of 1.4 mm (95% CI, 0.6-2.2 mm). Release of the entire anterior bundle caused a mean increase in ulnohumeral valgus joint gapping of 3.4 mm (95% CI, 2.4-4.3 mm). Release of the remaining individual structures each resulted in a mean increase in valgus joint gapping of ≤0.8 mm.

CONCLUSION

The results of the current cadaveric study suggest that different amounts of gapping are seen on SUS with sectioning of the medial elbow stabilizers. The hypothesis was confirmed with release of the anterior bundle of the UCL resulting in the greatest increase in joint gapping as measured by SUS.

CLINICAL RELEVANCE

This study illustrates that SUS can identify the contributions of each anatomic portion of the UCL and the flexor-pronator mass to ulnohumeral joint stability in a cadaveric model.

Sonographic assessment of the medial ulnar collateral ligament distal ulnar attachment

OBJECTIVES

The purpose of this study was to determine whether the long distal attachment of the medial ulnar collateral ligament (MUCL) can be delineated on sonography.

METHODS

We used 12 fresh-frozen cadaveric elbows for this study. We performed sonography of the elbow using a coronal-equivalent long-axis view of the MUCL. All sonographic examinations and measurements were performed by a board-certified, fellowship-trained musculoskeletal radiologist. Measurements were performed from the anteroinferior aspect of the medial epicondyle to the sublime tubercle and then from the sublime tubercle to the terminal fibers of the MUCL long ulnar attachment. We then measured the length of the MUCL from its attachment at the medial epicondyle of the humerus to the sublime tubercle and then from the sublime tubercle to the distal extent of its terminal fibers at the ulnar attachment with digital calipers.

RESULTS

On sonography, the average length of the MUCL from its humeral attachment to the sublime tubercle (transarticular) was 19.6 mm. The average length of the ulnar attachment was 27.9 mm. The MUCL was thickest (mediolateral dimension) at its humeral attachment and tapered as it coursed distally along the ulnar attachment. The MUCL was clearly identified on sonography and in all anatomic specimens. On gross measurement, the average lengths of the transarticular portion of the MUCL and its ulnar footprint were 21.5 and 30.2 mm, respectively.

CONCLUSIONS

We have successfully shown that the distal ulnar attachment of the MUCL can be visualized on high-resolution sonography. This preliminary work provides a framework for developing protocols for diagnosis of injuries to the distal ulnar collateral ligament.

The posterior transtriceps approach for intra-articular elbow diagnostics, definitely not forgotten

BACKGROUND/AIMS

The elbow is among the most common joints that are aspirated and/or injected. An intra-articular approach should be a convenient and a safe procedure with minimal risk of complications. Several approaches to access the elbow joint have been outlined in the literature, but a comparative study is lacking. This study evaluates the technical feasibility of the lesser-performed posterior transtriceps approach with MR arthrography and compares it to the classic lateral radiocapitellar approach.

PATIENTS AND METHODS

Using fluoroscopy guidance, MR arthrographies of the elbow were performed in 51 consecutive patients from 2006 to 2011. A classical lateral radiocapitellar approach was performed in 29 and a posterior transtriceps approach in 22 elbows. Studies were retrospectively reviewed with special attention to the extent of extra-articular contrast extravasation. This was a level IV diagnostic study.

RESULTS

Contrast leakage occurred in 12 radiocapitellar approaches, which caused a diagnostic dilemma in one subject. There was only a minimal amount of contrast leakage in five subjects using the transtriceps approach and no diagnostic dilemmas occurred. Results show no significant differences between the approaches. No complications occurred in the posterior transtriceps group and all MR arthrographies were diagnostic.

CONCLUSIONS

The posterior transtriceps approach is a technical feasible procedure, is easy to perform, and avoids a diagnostic dilemma in presumed injuries to the lateral collateral ligament complex. Our results show a tendency of even lesser amount of contrast leakage, further promoting a more widespread usage of the posterior transtriceps approach.

The history of clinical musculoskeletal radiology

The discipline of musculoskeletal radiology has evolved into a major imaging subspecialty in the years since the first use of x-rays to diagnose fractures. Musculoskeletal radiology expertise has experienced enormous developments in diagnostic sensitivity and specificity and in image-guided treatment options, in addition to technologic advances far beyond x-rays. Advances in cross-sectional imaging such as CT and MR imaging and educational and research endeavors have contributed further to the growth of musculoskeletal radiology as a distinct subspecialty.

The posterior transtriceps approach for elbow arthrography: a forgotten technique?

OBJECTIVE

To evaluate the technical feasibility of performing elbow MR arthrography via a posterior approach through the triceps.

MATERIALS AND METHODS

The images of 19 patients with elbow MR arthrography via a posterior transtriceps approach were retrospectively studied. The injections were performed by four musculoskeletal radiologists, using fluoroscopic guidance and a 22- or 25-gauge needle. The fluoroscopic and subsequent MR images were reviewed by two musculoskeletal radiologists and evaluated for adequacy of joint capsular distention, degree and location of contrast leakage, and presence of gas bubbles.

RESULTS

The injection was diagnostic in all 19 patients, with a sufficient amount of contrast agent seen in the elbow joint. No significant contrast leakage occurred in 12 patients who received injections of 8 cc or less of contrast agent, but moderate contrast leakage occurred in 6/7 patients who received injections of greater than 8 cc. Contrast leakage generally occurred within the triceps myotendinous junction. No gas bubbles were identified in the injected joints.

CONCLUSION

Patients often present for MR arthrography of the elbow with medial or lateral elbow pain. Contrast leakage during a radiocapitellar approach may complicate evaluation of the lateral collateral ligament or the common extensor tendon origin. Transtriceps MR arthrography offers an alternative to the more commonly used radiocapitellar approach. With injected volumes not exceeding 8 cc, the risk of significant contrast leakage is small. An advantage of the transtriceps injection is that contrast leakage through the posterior needle tract does not interfere with evaluation of the lateral structures.

Sonography of the superomedial part of the spring ligament complex of the foot: a study of cadavers and asymptomatic volunteers

OBJECTIVE

To evaluate the ability of high-resolution sonography for assessing the thickness and echogenicity of the superomedial part of the normal spring ligament in the foot in cadavers and asymptomatic volunteers.

MATERIALS AND METHODS

The superomedial part of the normal spring ligament of four cadaveric feet was imaged with a high-resolution linear array transducer. Upon localization, the ligament was injected with 0.1% methylene blue with sonographic guidance. A posteromedial approach was used to dissect the feet immediately following injection to confirm accurate identification of the ligament. The bilateral ligaments in 40 asymptomatic adult volunteers were subsequently imaged.

RESULTS

Surgical dissection confirmed the accurate injection of methylene blue into all four cadaveric ligaments. The superomedial part of the normal spring ligament was identified bilaterally in all of the 40 asymptomatic volunteers, with a mean thickness of 3 mm in longitudinal short axes. The ligament was echogenic relative to surrounding fat, and it was thinner in women. Differences in ligament measurements with respect to age, sex, side (left vs. right) and foot dominance were not significant. The volunteers' height, weight and body mass index had a weakly positive correlation with ligament thickness.

CONCLUSION

High-resolution ultrasound can be used to identify and measure the thickness of the superomedial part of the normal spring ligament. The provided baseline measurements for the normal ligament could prove valuable when assessing the abnormal ligament.

The role of ultrasound in the evaluation of sports medicine injuries of the upper extremity

The two major imaging modalities used for assessment of soft tissue injuries are ultrasound and MRI. Although ultrasound of the extremities is used only to a limited extent in the United States, it is widely used in many other countries for evaluation of extremity injuries. This article first considers the advantages and disadvantages of MRI and ultrasound. Understanding these differences will help the reader understand the role of ultrasound as compared with MRI in evaluating upper extremity injuries. The uses of ultrasound for evaluating sports medicine injuries in specific regions of the upper extremity are then reviewed. Where the data are available, the reported accuracy of ultrasound is compared with MRI for each type of injury.