Normal MR imaging anatomy of the elbow

Prognostic utility of an magnetic resonance imaging-based classification for operative versus nonoperative management of ulnar collateral ligament tears: one-year follow-up

BACKGROUND

A recently introduced classification of medial ulnar collateral ligament (UCL) tears has demonstrated high interobserver and intraobserver reliability, but little is known about its prognostic utility. The purpose of this study was to assess the relationship of the magnetic resonance imaging (MRI)-based classification system and nonoperative vs. operative management. Secondary objectives included subanalysis of baseball players.

METHODS

Eighty-five consecutive patients with UCL tears after a standardized treatment paradigm were categorized as operative vs. nonoperative. UCL tears of patients with a minimum of 1-year follow-up were retrospectively classified using the MRI-based classification system. Subanalyses for baseball players included return-to-play and return-to-prior performance.

RESULTS

A total of 80 patients (62 baseball players, 54 pitchers) met inclusion criteria. A total of 51 patients underwent surgery, and 29 patients completed nonoperative management. In baseball players, 59% of the proximal tears were treated nonoperatively and 97% of the distal tears were treated operatively; 100% of the proximal partial-thickness tears and 100% of the distal complete tears were treated nonoperatively and operatively, respectively. Patients with distal (odds ratio: 48.4, P < .0001) and complete (odds ratio: 5.0, P = .004) tears were more likely to undergo surgery. Baseball players, regardless of position, were determinants of operative management, and there was no difference in return-to-play clearance and return-to-prior performance between the operative and nonoperative groups.

CONCLUSION

A reliable 6-stage MRI-based classification addressing UCL tear grade and location may confer decision making between operative and nonoperative management. Complete and distal tears carry a markedly increased risk of failing nonoperative care compared with proximal, partial tears.

The Acutely Injured Elbow

The acutely injured elbow can present as a diagnostic challenge, encompassing a spectrum of conditions that involve the various osseous and soft tissue structures of this complex joint. Imaging plays a vital role in the management of these patients by providing an accurate interpretation of the underlying trauma sustained, which can have important implications on the preservation of joint function and stability. This article examines the mechanisms, patterns, classifications, and imaging findings of acute elbow injuries, providing key concepts for the radiologist in the interpretation of these injuries.

Clinical Utility of an MRI-Based Classification System for Operative Versus Nonoperative Management of Ulnar Collateral Ligament Tears: A 2-Year Follow-up Study

Background

A recently introduced classification system of medial ulnar collateral ligament (UCL) tears accounting for location and severity has demonstrated high interobserver and intraobserver reliability, but little is known about its clinical utility.

Purpose

The primary purpose of this study was to assess the relationship of the magnetic resonance imaging (MRI)-based classification system in predicting which athletes had success with nonoperative versus operative treatment after completing a standardized rehabilitation program. A secondary objective included return to play (RTP) and return to prior performance (RPP) analyses of baseball players.

Study Design

Cohort study; Level of evidence, 3.

Methods

After an a priori power analysis, 58 consecutive patients with UCL tears and a minimum of 2-year follow-up were retrospectively divided into 2 groups: those who successfully completed operative treatment and those who completed nonoperative treatment. The MRI-based classification stages accounting for UCL tear location and severity were compared between the nonoperative and operative groups. A subanalysis for baseball players, including RTP and RPP, was performed.

Results

A total of 58 patients (40 baseball players [34 pitchers]) met inclusion criteria. Of these patients 35 (32 baseball players [27 pitchers]) underwent surgery, and 23 (8 baseball players [7 pitchers]) underwent nonoperative management. No patients in the nonoperative arm crossed over to surgery after completing the rehabilitation program. Patients with distal tears (odds ratio, 48.0; P = .0004) and complete tears (odds ratio, 5.4; P = .004) were more likely to undergo surgery. Baseball players, regardless of position, were confounding determinants of operative management, although there was no difference in RTP and RPP between treatment arms.

Conclusion

A 6-stage MRI-based classification system addressing UCL tear location and severity may help early decision making, as patients likely to fail nonoperative treatment have complete, distal tears, whereas those with proximal, partial tears may be more amenable to nonoperative management.

Interobserver and Intraobserver Reliability of an MRI-Based Classification System for Injuries to the Ulnar Collateral Ligament

BACKGROUND

Despite improvements in understanding biomechanics and surgical options for ulnar collateral ligament (UCL) tears, there remains a need for a reliable classification of UCL tears that has the potential to guide clinical decision making.

PURPOSE

To assess the intra- and interobserver reliability of the newly proposed magnetic resonance imaging (MRI)-based classification for UCL tears. Secondary objectives included assessing the effect of additional views, discrimination between distal and nondistal tears, and correlation of imaging reads with intraoperative findings of the UCL.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

Nine fellowship-trained specialists from 7 institutions independently completed 4 surveys consisting of 60 elbow MRI scans with UCL tears using a newly proposed 6-stage classification system. The first and third surveys contained 60 coronal images, while the second and fourth contained the same images with coronal and axial views presented in a random order to assess intraobserver variability via the weighted kappa value and the effect of additional imaging views. Weighted kappa values were also calculated for each of the 4 surveys to acquire interobserver reliability. Reliability analysis was repeated through a 2-group classification analysis for distal and nondistal tears. Observer readings were compared with intraoperative UCL findings.

RESULTS

For the newly proposed 6-stage MRI-based classification, intra- and interobserver reliability demonstrated near perfect and substantial agreement, respectively. These values increased only when substratified into the 2-group distal and nondistal tear classification ( P < .05). The additional axial view did not statistically improve the agreement within and among readers. When compared with intraoperative findings from 30 elbows, observer readings were accurate for tear grade (partial and complete), proximal location, and distal location but not midsubstance tears.

CONCLUSION

The newly proposed 6-stage MRI-based classification utilizing grade and location of the injury had substantial to near perfect agreement among and within fellowship-trained observers.

[Assessment of ligament and tendon injuries of the elbow using magnetic resonance imaging]

An overview about the normal anatomy and frequent pathologies of tendons and ligaments of the elbow using MRI will be provided. The unique joint configuration and articulation, as well as passive ligamentous and active muscle structures as well as the unique configuration of the articulating components of the elbow contribute to joint stabilization. MRI is an essential imaging modality in patients with ligamentous injuries including the sequelae of joint dislocation as well as chronic pathologies such as long-standing and refractory tendinopathies. Ideally, when reporting MRI of the elbow, the joint is separated into its four compartments, anterior, posterior, medial and lateral, allowing precise, comprehensive and structured reporting.

Magnetic resonance imaging-based classification for ulnar collateral ligament injuries of the elbow

BACKGROUND

Magnetic resonance imaging (MRI) arthrography has been considered the gold standard for imaging ulnar collateral ligament (UCL) injuries. No classification system has been described for UCL tears to help discuss and guide treatment options. We propose that an MRI-based UCL classification system would correlate with valgus laxity and help predict surgical management.

METHODS

The MRIs from 240 patients who underwent UCL reconstruction were reviewed and classified according to a system based on severity and location of the UCL injury. Bilateral elbow valgus stress radiographs were used to compare the amount of valgus laxity associated with each grade of UCL injury. Additional data from the imaging review included intraligamentous calcifications, T-sign presence, and a newly described "vacuum sign."

RESULTS

The amount of valgus stress opening increased with the classification severity as follows: type I, 0.13 mm; type II, 0.20 mm; type III, 0.63 mm; and type IV, 0.76 mm.

CONCLUSIONS

We propose a new classification for UCL injuries based on MRI findings that helps predict valgus laxity, improve communication, and guide treatment for UCL pathology in throwing athletes.

Elbow magnetic resonance imaging: imaging anatomy and evaluation

The elbow is a complex joint. Magnetic resonance imaging (MRI) is often the imaging modality of choice in the workup of elbow pain, especially in sports injuries and younger patients who often have either a history of a chronic repetitive strain such as the throwing athlete or a distinct traumatic injury. Traumatic injuries and alternative musculoskeletal pathologies can affect the ligaments, musculotendinous, cartilaginous, and osseous structures of the elbow as well as the 3 main nerves to the upper limb, and these structures are best assessed with MRI.Knowledge of the complex anatomy of the elbow joint as well as patterns of injury and disease is important for the radiologist to make an accurate diagnosis in the setting of elbow pain. This chapter will outline elbow anatomy, basic imaging parameters, compartmental pathology, and finally applications of some novel MRI techniques.

The existence of cords in olecranon bursae

BACKGROUND

The purpose of this study was to document the existence of transverse cords in olecranon bursae in patients undergoing excision of the bursa and to describe the unique clinical presentation of patients with these cords.

METHODS

A retrospective study was performed on 24 patients who had surgery to excise an olecranon bursa between 2006 and 2011. The patient's history, preoperative radiographs, ultrasound images, intraoperative photographs, and findings on histologic analysis were reviewed in all cases.

RESULTS

Nine olecranon bursae had cords (cord group) and 15 did not have cords (noncord group). All patients in the cord group were male manual laborers, and nearly all had olecranon enthesophytes (n = 8). Patients in the noncord group had associated medical conditions or an infection. A higher level of satisfaction was reported in the noncord group after surgical excision.

CONCLUSION

This study documents the existence of transverse cords oriented at right angles to the long axis of the olecranon. Olecranon bursae with cords have a unique presentation and are found in male manual workers, are nearly always associated with an olecranon enthesophyte, and do not present with infections.

Magnetic resonance imaging of the long bones of the upper extremity

The long bones of the upper extremity are often overlooked in favor of addressing their intervening joints. However, there are a wide variety of pathologic processes that can involve these anatomic segments. To better understand the complex anatomy of the upper extremity, this article is divided into sections describing the osseous, muscular, and neurovascular anatomy of the arm and forearm using a compartmental approach. The discussion touches on a few common normal variants and their potential functional consequences. The upper extremity joints of the shoulder, elbow, and wrist are addressed separately.

Magnetic resonance imaging of the elbow in athletes

Acute and chronic elbow pain is common, particularly in athletes. Although plain radiographs, ultrasound, and computed tomography all have a role to play in the investigation of elbow pain, magnetic resonance imaging (MRI) has emerged as the imaging modality of choice for diagnosis of soft tissue disease and osteochondral injury around the elbow. The high spatial resolution, excellent soft-tissue contrast, and multiplanar imaging capabilities of MRI make it ideal for evaluating the complex joint anatomy of the elbow. This article reviews imaging of common disease conditions occurring around the elbow in athletes, with an emphasis on MRI.

Reprint of imaging of the elbow: a review of imaging findings in acute and chronic traumatic disorders of the elbow

Traumatic injuries of the elbow are frequent in patients of all ages but are particularly common in young children and adolescents engaged in normal play and athletic competition. Injury may result primarily due to direct trauma or may be secondary to transmission of forces through the elbow following a fall on an outstretched hand. In middle-aged and older individuals, chronic repetitive injuries tend to predominate. In all patients, radiographs remain the initial imaging study of choice. Many patients, however, may need advanced cross-sectional imaging (i.e. MRI, CT, or ultrasound) either at presentation or during the course of their treatment and follow-up. This article reviews the imaging appearance of common acute and chronic traumatic disorders of the elbow.

Imaging of the elbow: a review of imaging findings in acute and chronic traumatic disorders of the elbow

Traumatic injuries of the elbow are frequent in patients of all ages but are particularly common in young children and adolescents engaged in normal play and athletic competition. Injury may result primarily due to direct trauma or may be secondary to transmission of forces through the elbow following a fall on an outstretched hand. In middle-aged and older individuals, chronic repetitive injuries tend to predominate. In all patients, radiographs remain the initial imaging study of choice. Many patients, however, may need advanced cross-sectional imaging (i.e. MRI, CT, or ultrasound) either at presentation or during the course of their treatment and follow-up. This article reviews the imaging appearance of common acute and chronic traumatic disorders of the elbow.