Return to Play in Youth Athletes: Role of the Radiologist with Focus on the Upper Extremity

Increase in youth sports participation, longer duration of play, and earlier starting points have increased the prevalence of acute and repetitive overuse musculoskeletal injuries. This rise in injury rates has led to increased efforts to better understand the susceptible sites of injury that are unique to the growing immature skeleton. Upper extremity injuries are currently the best studied, particularly those that occur among pediatric baseball players and gymnasts. The weak link in skeletally immature athletes is the growth plate complex that includes those injuries located at the epiphyseal and apophyseal primary physes and the peripherally located secondary physes. This article reviews the anatomy and function of these growth plate complexes, followed by a discussion of the pathophysiologic mechanisms, spectrum of imaging findings, and existing evidence-based guidelines for injury prevention and return to play.

Normal ossification of the glenoid mimicking a glenoid fracture in an adolescent patient: a case report

A 13-year-old male was diagnosed with a glenoid fracture following direct shoulder trauma, for which surgical treatment was considered. After referral to a center for pediatric orthopedic care, physical examination, contralateral shoulder X-ray, and detailed computed tomography examination ruled out the presence of fracture; these findings were later confirmed by magnetic resonance imaging. Normal ossification patterns in the adolescent shoulder may simulate a fracture in traumatic settings. To accurately diagnose and manage pediatric shoulder pathology, orthopedic surgeons must be aware of the normal anatomy of the growing shoulder, its secondary ossification centers, and growth plates.

Physeal injuries of the clavicle: pediatric counterparts to adult acromioclavicular and sternoclavicular joint separations

The epiphyses at the medial and lateral ends of the clavicle are small, ossify relatively late, and may not fuse until early adulthood. Because of this unique anatomy, pediatric and young adult injuries that involve the clavicle often differ from the patterns typically seen in older adults. Clavicular trauma that affects the acromioclavicular joint laterally or sternoclavicular joint medially often results in a physeal fracture and as such, can go unrecognized or be mistaken for a joint dislocation. Radiographic assessment is challenging, particularly when the epiphysis is not yet ossified. However, MR imaging allows for visualization of the cartilage, periosteum and perichondrium, and ligaments of the affected joints. Lateral clavicle physeal injuries can be categorized by the Dameron and Rockwood system, the pediatric correlate to the Rockwood classification of adult acromioclavicular joint injuries. Medial clavicle physeal fractures, similar to adult sternoclavicular joint dislocations, may result in anterior or posterior displacement. Because of their great ability to heal and remodel, clavicular physeal fractures respond better to conservative management than true acromioclavicular or sternoclavicular joint dislocations. Therefore, it is essential to recognize the true nature of these injuries, as there are implications for successful treatment and appropriate prognosis.

Common Upper Extremity Injuries in Pediatric Athletes

PURPOSE OF REVIEW

The aim of this study is to review the most recent literature on common upper extremity injuries in pediatric athletes and discuss their diagnosis, management, and outcomes. We also highlight ultrasound as a tool in their evaluation.

RECENT FINDINGS

Shoulder conditions presented include little league shoulder, glenohumeral rotation deficit, acute traumatic shoulder dislocation, and multidirectional shoulder instability. Elbow conditions include capitellar OCD, medial epicondyle avulsion fracture, and medial epicondylitis. We also review scaphoid fractures and gymnast wrist. Not all physeal injuries lead to long-term growth disruption. Ultrasound has been shown to be useful in the diagnosis of scaphoid fracture, medial epicondyle avulsion fractures, and capitellar OCD. It can also be helpful in assessing risk for shoulder and elbow injuries in overhead athletes. There is a rising burden of upper extremity injuries among pediatric athletes. Knowledge of their sport specific mechanics can be helpful in diagnosis. As long-term outcome data become available for these conditions, it is clear, proper diagnosis and management are critical to preventing adverse outcomes. We highlight many of these injuries, best practice in care, and controversies in care in hopes of improving outcomes and preventing injury for pediatric athletes.

Apophyseal Avulsion of the Rectus Femoris Tendon Origin in Adolescent Soccer Players

Apophyseal avulsions of the rectus femorus tendon (RFT) at the anterior inferior iliac spine (AIIS) can occur in adolescents, often while performing soccer. Patient-reported outcomes (PROMs) and time to return to sport of these patients are relatively unknown. Therefore, the aim of this study was to assess the PROMs and return to sports of patients with AIIS avulsions and compare the results with those reported in the literature. This is a case series of seven consecutive patients presenting at our hospital between 2018 and 2020 with an apophyseal avulsion of the RFT from the AIIS. The patients were assessed with use of the WOMAC and Tegner scores and return to sports was evaluated. All patients were male soccer players (median age 13 years; range, 12–17). They were all initially treated non-operatively. One of the patients subsequently needed excision surgery of a heterotopic ossification because of non-transient hip impingement. All other patients recovered after a period of relative rest. Median time to return to sports was 2.5 months (range, 2–3). At a median follow-up of 33 months (range, 18–45), the WOMAC (median, 100; range, 91–100) and Tegner scores (median, 9; range, 5–9) were high. In accordance with the existing literature, most patients with apophyseal avulsions of the AIIS recover well with non-operative treatment. However, the avulsion can lead to hip impingement due to heterotopic ossifications possibly needing surgical excision. Sport resumption is achievable after 2–3 months, and patient-reported outcomes are highly satisfactory in the long term.

Increase in surgical fixation of pediatric midshaft clavicle fractures since 2008

BACKGROUND

Clavicle fractures in children have traditionally been treated non-operatively. In adults, a great increase in operative treatment has been reported. We aimed to analyze the respective trend and potential explanatory factors in children.

METHODS

This is a single-institution retrospective study in a subregion in Northern Finland. The ICD-code S42.0 was used to identify the cases in the hospital registry. Altogether, 214 children, aged < 16, with consecutive clavicle fractures were first enrolled in the area during 2008-2019. Hospital journals and radiographs were reviewed. After lateral and medial fractures and patients living outside the area were excluded, final study population was 172. The respective population at risk was extracted by Statistics Finland. Predictive factors and annual rates of operative treatment as adjusted for 100,000 children at risk were determined.

RESULTS

The rate of the surgical treatment of clavicle fractures increased from zero in 2008 to 10.8 in 2019 per 100,000 age-adjusted children (β = 0.864, 95% confidential intervals (CI) 0.4 to 1.4). There was a rise in the rate of surgery from 2.6% (2014-16) to 16.1% (2017-19) (diff. 13.5, 95% CI 1.7 to 23.3%). A displacement > 15 mm and a shortening of > 15 mm were associated with the increased risk of surgery but did not change during the study period. Age > 9 years increased the risk of surgery; the mean age increased from 5.5 years (2008-10) to 8.5 years (2017-19). There was a 3.6-fold increase in sports-related fractures (95% CI 7.4 to 26.4). The severity of the fractures did not change.

CONCLUSIONS

There has been an increasing trend in the surgical fixation of pediatric middle shaft clavicle fractures since 2008. The available literature does not support the trend.

Avulsion injuries: an update on radiologic findings

Avulsion injuries result from the application of a tensile force to a musculoskeletal unit or ligament. Although injuries tend to occur more commonly in skeletally immature populations due to the weakness of their apophysis, adults may also be subject to avulsion fractures, particularly those with osteoporotic bones. The most common sites of avulsion injuries in adolescents and children are apophyses of the pelvis and knee. In adults, avulsion injuries commonly occur within the tendon due to underlying degeneration or tendinosis. However, any location can be involved in avulsion injuries. Radiography is the first imaging modality to diagnose avulsion injury, although advanced imaging modalities are occasionally required to identify subtle lesions or to fully delineate the extent of the injury. Ultrasonography has a high spatial resolution with a dynamic assessment potential and allows the comparison of a bone avulsion with the opposite side. Computed tomography is more sensitive for depicting a tiny osseous fragment located adjacent to the expected attachment site of a ligament, tendon, or capsule. Moreover, magnetic resonance imaging is the best imaging modality for the evaluation of soft tissue abnormalities, especially the affected muscles, tendons, and ligaments. Acute avulsion injuries usually manifest as avulsed bone fragments. In contrast, chronic injuries can easily mimic other disease processes, such as infections or neoplasms. Therefore, recognizing the vulnerable sites and characteristic imaging features of avulsion fractures would be helpful in ensuring accurate diagnosis and appropriate patient management. To this end, familiarity with musculoskeletal anatomy and mechanism of injury is necessary.

Uniquely pediatric upper extremity injuries

The pediatric population is prone to unique upper extremity injuries that are not typically seen in adults. The normal dynamic maturation pattern of ossification centers and open physis can potentially confuse radiologists who are not familiar with the pediatric patients. In this review article, we discuss the normal anatomy and commonly encountered acute and chronic upper extremity injuries such as supracondylar distal humeral fracture and osteochondritis dissecans, in pediatric patients. Diagnosing the correct type of fracture (e.g., buckle vs Salter-Harris) is important for proper management of the injury. With an increasing number of adolescents participating in competitive sports, specific sports related injuries such as little league shoulder, gymnast wrist, and medial epicondyle apophysitis, are also discussed in this review. We examine late complications of injuries, such as physeal bar formation and fishtail deformity of the distal humerus.

Pediatric Musculoskeletal Trauma: Upper Limb

Pediatric upper extremity injuries, acute and chronic due to overuse, are commonly encountered in the clinical setting. However, interpretation of imaging studies is often challenging in pediatric patients because of changing postnatal skeletal development and the broad spectrum of pathology that can potentially occur. This article discusses normal skeletal development and the pathomechanics of skeletal injuries in pediatric patients. It also outlines a framework for imaging as it pertains to the pediatric upper extremity, with specific emphasis on acute and chronic injuries to the shoulder, elbow, forearm, and wrist.

Contemporary imaging of the pediatric shoulder: pearls and pitfalls

In skeletally immature patients, the presence of growth plates and articular cartilage of the shoulder can create a predisposition for unique injuries not observed in adults. Furthermore, increasing participation in sports by children and adolescents appears to be leading to a corresponding increase in the number of sports-related injuries. The importance of radiologists being familiar with pediatric shoulder imaging and its associated injuries is therefore growing. In this article, we review the normal development and maturation pattern of ossification centers of the shoulder from the early gestational period through adolescence. Brachial plexus birth palsy, physeal injuries, shoulder dislocation, and internal impingement are discussed within the context of the child's age and the mechanism of injury to guide radiologists to a correct diagnosis.

Physeal Injuries of the Coracoid Process Are Closely Associated With Sports Activities: A Systematic Review

Background:

Physeal injuries of the coracoid process are rare but may be increasing because of increased participation of youth in year-round sports.

Purpose:

To analyze reported physeal and apophyseal injuries of the coracoid process.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

PubMed and Scopus were searched using the terms scapula fracture and coracoid fracture. The inclusion criteria were English full-text articles describing coracoid fracture as well as articles that described patient characteristics and presented appropriate images. The exclusion criteria were descriptive cases without images as well as those lacking appropriate images. Citation tracking was conducted to find additional articles and full-text articles written in other languages. Articles were included if they reported physeal injury or judged to involve physeal injury based on the provided images.

Results:

Overall, 22 studies including 32 patients (29 males, 3 females) were identified. All but 2 patients were younger than 18 years of age, and 66% (21/32) had sustained injuries during or as a result of participation in sporting activities. The affected site was the physis at the base in 18 patients, an intra-articular fracture in the primary coracoid ossification center combined with the subcoracoid ossification center to form an intra-articular fracture in 5, the apophysis of the tip in 3, the apophysis of the angle in 5, and uncertain in 1. Eleven patients had concurrent acromioclavicular injuries. The injury was acute in 23 patients, chronic in 6, and traumatic nonunion in 3. Among 21 cases in which treatment methods and outcomes were described, 21% of the acute cases (4/19), and 2 of the 3 nonunions were surgically treated. Only 1 study used a widely accepted evaluation method. Follow-up periods ranged from 6 weeks to 2 years. Outcomes were generally excellent for nonoperative and operative treatment and without any serious complications.

Conclusion:

Coracoid physeal injuries occurred most commonly in patients aged 13 to 15 years of age (71%) and were usually sustained during or as a result of sports activities (66%). The most common injury site was the physis at its base. The cause of these injuries is probably severe or repeated traction of the attached muscles and ligaments. The majority of these injuries can be successfully treated nonoperatively.

Sex-based differences in pediatric supracondylar humerus fractures

Supracondylar humerus (SCH) fractures are reported to be approximately twice as common among boys as among girls. Little is known about sex-associated differences in fracture patterns and complications. We compared the incidence of pediatric SCH fractures, injury mechanism (high-energy or low-energy), fracture subtypes, associated neurologic injuries, and treatment types by patient sex.We reviewed 1231 pediatric SCH fractures treated at 1 center from 2008 to 2017, analyzing sex distributions overall and by year and fracture subtype. We noted patient demographic characteristics, injury mechanisms, neurologic injuries, and treatments (nonoperative or operative). Binomial 2-tailed, chi-squared, and Student's t tests were used for analysis. Multiple logistic regression was performed to assess associations between sex, age, and injury mechanism. Alpha = 0.05.We found no significant difference in the distribution of girls (52%) vs boys (48%) in our sample compared with a binomial distribution (P = .11). Annual percentages of fractures occurring in girls ranged from 46% to 63%, and sex distribution did not change significantly over time. The mean (± standard deviation) age at injury was significantly younger for girls (5.5 ± 2.5 years) than for boys (6.1 ± 2.5 years) (P < .001). High-energy injury mechanism was associated with older age (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.03-1.06) but not male sex (OR, 1.04; 95% CI, 0.98-1.1). The overall incidence of neurologic injury was 9.5% but boys did not have greater odds of sustaining neurologic injury (OR, 1.03; 95% CI, 1.0-1.1). We found no sex-associated differences in the distribution of Gartland fracture subtypes (P = .13) or treatment type (P = .39).Compared with boys, girls sustain SCH fractures at a younger age. SCH fractures were distributed equally among girls and boys in our sample. Patient sex was not associated with fracture subtype, injury mechanism, neurologic injury, or operative treatment. These findings challenge the perception that SCH fracture is more common in boys than girls.Level III, retrospective study.

Clavicles continue to grow beyond skeletal maturity: radiographic analysis of clavicle length in adolescents and young adults

There has been minimal research regarding the clavicle's growth and its clinical implications in the late adolescent and early adult population. Previous studies have evaluated postnatal clavicle growth to age 18 without analysing growth through the age of secondary ossification center closure. The purpose of this study was (1) to determine clavicle length and age-related growth in males and females from age 12 to 25 years and (2) to specifically analyse clavicle growth in late adolescence. This was a retrospective analysis of chest radiographs in patients aged 12-25 years. The ruler tool was used to measure clavicle length. Mean values were tabulated for each year of age in males (n = 697) and females (n = 672). Mean right clavicle growth significantly increased from age 12 to 25 in both males and females (P < 0.0001). In males, the increase from age 16 to 25 was 17.5 mm, representing 10.6% of total clavicle length (P < 0.0001). In females, the increase from age 14 to 25 was 7.7 mm, representing 5.2% of total clavicle length (P < 0.0001). We found that from skeletal maturity to the closure of the secondary ossification center, growth was 17.5 mm (10.6% of total clavicle length) in males and 7.7 mm (5.2% of total clavicle length) in females. During their growth spurts, the adolescent male and female clavicle have growth potentials very similar to previous studies of radius growth. Understanding these clavicular growth potentials can influence operative vs. nonoperative management decisions by orthopaedic surgeons. Level of evidence: Level III.

Normal Glenoid Ossification in Pediatric and Adolescent Shoulders Mimics Bankart Lesions: A Magnetic Resonance Imaging-Based Study

PURPOSE

The purpose of this descriptive study was to define patterns of ossification and fusion of growth centers around the pediatric and adolescent glenoid as a function of age using 3-dimensional, frequency-selective, fat-suppressed spoiled gradient recalled echo magnetic resonance (MR) imaging sequences, with a particular focus on the anterior glenoid rim because of its clinical relevance as a potential confounder of glenohumeral instability.

METHODS

Picture Archiving and Communication System records at an urban academic tertiary care orthopaedic facility from October 2005 to December 2018 were queried for shoulder MRI in patients aged 9 to 17 years. Patients were excluded if they had any diagnoses that could alter glenoid development. All images were independently evaluated by a musculoskeletal fellowship-trained radiologist. Secondary ossification centers were characterized as cartilage anlage, ossified, or fused at 3 anatomic sites: the anterior glenoid rim, coracoid, and superior glenoid rim.

RESULTS

A total of 250 MR examinations (143 males, 107 females) were assessed in this study. The glenoid develops in a predictably sequential manner with ossification at the anterior glenoid rim lagging behind the coracoid and superior glenoid rim. The earliest age of anterior glenoid rim ossification was 11 years for both males (range 11-17) and females (range 11-12). Anterior glenoid rim ossification peaked at age 16 among males (34.8%, 8/23) and age 11 among females (27.3%, 3/11).

CONCLUSIONS

Glenoid ossification and fusion progress in a predictable and chronological manner. This pattern should be used as a guideline when interpreting pediatric shoulder MRI examinations. In particular, an anterior glenoid ossification center should not be confused with an anterior glenoid injury (e.g., Bankart lesion), particularly in males 11 to 17 years old and females 11 to 12 years old.

LEVEL OF EVIDENCE

IV (case series).

Coracoclavicular Double-Button Fixation of Displaced Lateral Clavicular Fracture in a Patient without Coracoid Process

Background

Displaced distal clavicular fractures are generally operated on because of the high nonunion rate after nonoperative treatment. Several surgical techniques have been developed to reduce the nonunion rate and improve functional outcomes. One of them is closed reduction and minimally invasive coracoclavicular double-button fixation, which requires the integrity of the coracoid process to be performed.

Case Summary

We present a 35-year-old male patient who had been successfully subjected to a modified Latarjet procedure for glenohumeral instability with bony defect treatment, and 7 months later suffered a distal clavicle fracture in his ipsilateral shoulder. With a CT scan, we analyzed the coracoid remnant size (7 mm), and we consider it enough to perform a minimally invasive double-button technique, using this remnant as a distal fixation.

Postoperative and Follow-Up

Radiographic and clinical fracture union occurred 10 weeks after the procedure. The patient returned to sports at the same level he had before surgery and achieved full strength and range of motion.

Conclusion

Closed reduction and minimally invasive double-button fixation of displaced distal clavicular fractures is a safe, reproducible, and versatile technique, which can even be performed without an intact coracoid process.

The distal radial physis: Exploring normal anatomy on MRI enables interpretation of stress related changes in young gymnasts

Rationale: Explore the MRI-appearance of the healthy distal radial physis and the distribution of stress-related changes in physeal thickness in young gymnasts to aid in the understanding of the pathophysiological process of stress-related physeal injury. Methods: Symptomatic gymnasts with clinically suspected overuse injury of the distal radial physis and age and gender-matched asymptomatic gymnasts and healthy non-gymnasts underwent an MRI-scan of the wrist. A cartilage-specific sequence was used to obtain three-dimensional reconstructions of the distal radial physis. Heat maps and line charts of these reconstructions visualised distribution of physeal thickness per study group and were used to explore differences between study groups. Symptomatic gymnasts displaying the most profound physeal widening (n = 10) were analysed separately. Results: Twenty-seven symptomatic - (skeletal age 12.9 ± 1.5 years), 16 asymptomatic - (skeletal age 12.8 ± 1.9 years) and 23 non-gymnasts (skeletal age 13.6 ± 1.9 years) were included for analysis. Physes of healthy non-gymnasts had a thin centre and increased in thickness towards the borders. Gymnasts demonstrated an increase in thickness of the entire physeal surface. In symptomatic gymnasts increase in physeal thickness was most prominent at the volar side when compared to asymptomatic gymnasts and non-gymnasts. Conclusion: The healthy distal radial physis is characterised by a thin centre surrounded by thicker borders. Stress applied to the wrist during gymnastics causes an overall increase in physeal thickness. Profound thickness increase is present at the volar side of the physis mainly in symptomatic gymnasts. These results can help unravel the pathophysiological mechanism of stress-related physeal injury in gymnasts and aid early injury identification.

Normal development imaging pitfalls and injuries in the pediatric shoulder

The skeletal maturation of the shoulder has been well documented on radiographic and cadaveric studies. Recent increased use of MRI has provided increased understanding of the soft-tissue and osseous changes that occur during development. Thus recognizing normal maturation, imaging manifestations and pitfalls is crucial when evaluating the pediatric shoulder joint. At birth, the humeral diaphysis, midportion of the clavicle, and the body of the scapula are ossified, while the remainder of the bones of the shoulder are composed of non-ossified cartilaginous precursors. During growth, cartilaginous apophyses and epiphyses of the shoulder develop numerous secondary ossification centers, which fuse with the primary ossification centers to form the complete bony components of the shoulder. Additionally changes in the morphology of the growth plates as well as marrow signal occur in an organized manner. This paper affords the reader with an understanding of the normal development of three major components of skeletal maturation in the shoulder: ossification centers, growth plates and marrow signal. These topics are further subdivided into the glenoid, proximal humerus and acromioclavicular joint. We also provide a focus on distinguishing normal anatomy from imaging pitfalls related to skeletal maturation.

Magnetic resonance imaging of elbow injuries in children

Evaluating elbow injuries is challenging because of the complex anatomy of the joint. In children, injury patterns depend on the sports-specific mechanism as well as the stage of skeletal maturity. This article reviews the anatomy of the elbow and common injury patterns seen in children, with an emphasis on MRI and the throwing athlete. Imaging pitfalls specific to children are described.

The Acutely Injured Wrist

Wrist traumas are a frequent clinical emergency for which instrumental imaging assessment is required. The purpose of this article is to review the role of imaging assessment of traumatic wrist injuries, with particular reference to fractures and associated lesions.

Damage of the distal radial physis in young gymnasts: can three-dimensional assessment of physeal volume on MRI serve as a biomarker?

Objective

To explore the use of quantitative volume assessment to identify the presence and extent of stress-related changes of the distal radial physis in gymnasts with suspected physeal injury, asymptomatic gymnasts, and non-gymnasts.

Methods

Symptomatic gymnasts with clinically suspected distal radial physeal injury, asymptomatic gymnasts, and non-gymnasts (n = 69) were included and matched on skeletal age and sex. Volume measurements were performed on coronal water selective cartilage MRI images by creating three-dimensional physeal reconstructions semi-automatically using active-contour segmentation based on image-intensity thresholding. Inter- and intra-rater reliability of the measurements were assessed using intra-class correlation coefficients (ICC) for absolute agreement.

Results

Twenty-seven symptomatic-, 18 asymptomatic-, and 24 non-gymnasts were included with a median age of 13.9 years (interquartile range (IQR) 13.0–15.0 years). Median physeal volume was significantly increased (p < 0.05) in symptomatic- (971 mm³, IQR 787–1237 mm³) and asymptomatic gymnasts (951 mm³, IQR 871–1004 mm³) compared with non-gymnasts (646 mm³, IQR 538–795 mm³). Inter-rater (ICC 0.96, 95% CI 0.92–0.98) and intra-rater (ICC 0.93, 95% CI 0.85–0.97) reliability of volume measurements were excellent. Of the 10 participants with the highest physeal volumes, nine were symptomatic gymnasts.

Conclusion

Increased volume of the distal radial physis can reliably be assessed and is a sign of physeal stress that can be present in both symptomatic- and asymptomatic gymnasts, but gymnasts with suspected physeal injury showed larger volume increases. Future studies should explore if volume assessment can be used to (early) identify athletes with or at risk for physeal stress injuries of the wrist.

Key Points

• The volume of the distal radial physis can be reliably assessed by creating three-dimensional physeal reconstructions.

• Stress-related volume increase of the distal radial physis is present in symptomatic and asymptomatic gymnasts.

• Gymnasts with clinically suspected physeal injury showed larger volume increases compared with asymptomatic gymnasts and may therefore be a valuable addition in the (early) diagnostic workup of physeal stress injuries.

Frequently Missed Fractures in Pediatric Trauma: A Pictorial Review of Plain Film Radiography

Missed fractures are common in pediatric trauma patients. Pediatric bone differs from adult bone in its composition and response to injury, leading to fracture patterns that may be subtle, radiographically unfamiliar, and challenging to distinguish from normal variation. Familiarity with the unique fracture types of the pediatric skeleton and site-specific injury patterns is critical, because prompt diagnosis can significantly alter clinical management and outcome. This article examines the unique features of pediatric bone contributing to missed fractures, the incidence of missed fractures, common injury types of the pediatric skeleton, and frequently missed site-specific fracture patterns, highlighting problem-solving techniques for challenging cases.

The elbow: review of anatomy and common collateral ligament complex pathology using MRI

The elbow is a complex joint whose stability is imparted by osseous and soft-tissue constraints. Anatomical and biomechanical knowledge of the supporting structures that provide stability to the medial and lateral elbow is essential to correctly interpret the pathological findings. Conventional MRI and MR arthrography are the imaging modalities of choice in the evaluation of elbow ligament injuries. Elbow instability can be classified according to timing (acute, chronic, or recurrent), the direction of displacement, the degree of displacement, and the articulations involved. This article reviews the MR imaging protocols recommended for each diagnosis and the normal anatomy and biomechanical aspects of the medial and lateral collateral ligament complex. We also present multiple cases of typical and atypical patterns of injury.

Gymnast's wrist in a 12-year-old female with MRI correlation

We describe a case of chronic overuse injury of the distal radial physis (gymnast's wrist). While the radiographic appearance of this entity has been reported, there are limited studies highlighting the MR appearance of this entity. This lesion is being seen with increasing frequency in young, elite gymnasts. If this injury goes unrecognized, there is potential for abnormal osseous development, with premature physeal fusion, abnormal joint inclination and even Madelung deformity.

Systematic assessment of the growth plates of the wrist in young gymnasts: development and validation of the Amsterdam MRI assessment of the Physis (AMPHYS) protocol

Objectives

To develop and validate a protocol for MRI assessment of the distal radial and ulnar periphyseal area in gymnasts and non-gymnasts.

Methods

Twenty-four gymnasts with wrist pain, 18 asymptomatic gymnasts and 24 non-gymnastic controls (33 girls) underwent MRI of the wrist on a 3T scanner. Sequences included coronal proton density-weighted images with and without fat saturation, and three-dimensional water-selective cartilage scan and T2 Dixon series. Skeletal age was determined using hand radiographs. Three experienced musculoskeletal radiologists established a checklist of possible (peri)physeal abnormalities based on literature and clinical experience. Five other musculoskeletal radiologists and residents evaluated 30 MRI scans (10 from each group) using this checklist and reliability was determined using the intraclass correlation coefficient (ICC) and Fleiss' kappa. A final evaluation protocol was established containing only items with fair to excellent reliability.

Results

Twenty-seven items were assessed for reliability. Intra-rater and inter-rater agreement was good to excellent (respective ICCs 0.60-0.91 and 0.60-0.78) for four epiphyseal bone marrow oedema-related items, physeal signal intensity, metaphyseal junction and depth of metaphyseal intrusions. For physeal thickness, thickness compared with proximal physis of first metacarpal, metaphyseal intrusions, physeal connection of intrusions and metaphyseal bone marrow signal intensity, intra-rater agreement was fair to excellent (ICC/kappa 0.55-0.85) and inter-rater agreement was fair (ICC/kappa 0.41-0.59). Twelve items were included in the final protocol.

Conclusion

The Amsterdam MRI assessment of the Physis protocol facilitates patient-friendly and reliable assessment of the (peri)physeal area in the radius and ulna.

Ultrasound evaluation of stress injuries and physiological adaptations in the fingers of adolescent competitive rock climbers

BACKGROUND

The impact of high-intensity, repetitive training on the fingers of adolescent climbers is relatively unknown.

OBJECTIVE

To evaluate this effect by ultrasound (US) and to confirm some findings by magnetic resonance imaging (MRI).

MATERIALS AND METHODS

The US study was performed in 20 adolescent rock climbers (ages 10-17 years) and 6 non-climbing controls (ages 11-15 years). US was used to examine the third digit of the right hand for differences in thickness of soft tissue, flexor and extensor tendon, volar plate and bony and growth plate adaptations. In four climbers with finger deformity or pain, 3-T MR images were compared with US findings. Number of hours/week and years of climbing were used to group climbers in three levels (3=most intense training). Mann-Whitney test was used for statistical analysis.

RESULTS

Compared with non-climbing controls, climbers demonstrated significantly thicker flexor tendons, volar plates and soft tissues. Joint effusions were found in 13/19 (68%) climbers. Significant phalangeal malalignment was seen in 10/19 (53%) climbers. Growth plate deformities were identified in three level 3 climbers. US findings correlated with MRI for effusions, phalangeal growth plate injury, malalignment and adaptive changes. MRI additional showed capsule rupture (n=1), stress fracture (n=1) and phalangeal physeal stress injury (n=1).

CONCLUSION

Competitive rock climbing results in physiological adaptations in the fingers, an example being significant soft-tissue hypertrophy of the flexor. US demonstrated several non-physiological changes in response to repetitive stress in half of the climbers. MRI showed additional stress injuries to the growth plate, joints and bone.

Growth plate injury at the base of the coracoid: MRI features

PURPOSE

To assess the MRI features of growth plate injury at the base of the coracoid process.

MATERIALS AND METHODS

Subjects were identified through retrospective search of our department imaging database and teaching files and the teaching files of two outside academic institutions. The coracoid base growth plate was examined with attention to widening, irregularity, abnormal signal intensity of the growth plate, and the presence of adjacent soft tissue edema. The apposing coracoid and scapular bony surfaces were examined for signal intensity and morphology.

RESULTS

Shoulder MRIs in eight patients with coracoid base growth plate disturbances were retrospectively reviewed (7 males, 1 female, mean age 15 years). Growth plate injury manifested as widening, irregularity and increased signal, apposing bony marrow edema and hypertrophy, and surrounding soft tissue edema. Five subjects were athletes (football, archery, basketball, swimming, rugby), two had a history of neuromuscular disorders, and one subject presented after a fall. Clinical indications included: rule out labral tear (n = 3), rule out rotator cuff tear or fracture after fall (n = 1), nonspecific pain (n = 1), shoulder subluxation, rule out glenoid pathology (n = 1, patient with underlying neuromuscular disorder), muscular dystrophy with shoulder pain (n = 1), and impingement (n = 1). Coracoid growth plate injury was not suspected clinically in any of the patients.

CONCLUSION

Awareness of the imaging appearance of coracoid base growth plate injury can aid in a more accurate diagnosis of shoulder MRI studies in young pediatric athletes. While uncommon, coracoid growth plate injury should be considered when assessing children with shoulder symptomatology.

Physical exam of the adolescent shoulder: tips for evaluating and diagnosing common shoulder disorders in the adolescent athlete

PURPOSE OF REVIEW

In the young athlete, the shoulder is one of the most frequently injured joints during sports activities. The injuries are either from an acute traumatic event or overuse. Shoulder examination can present some challenges; given the multiple joints involved, the difficulty palpating the underlying structures, and the potential to have both intra- and/or extra-articular problems.

RECENT FINDINGS

Many of the shoulder examination tests can be positive in multiple problems. They usually have high sensitivity but low specificity and therefore low predictive value. The medical history coupled with a detailed physical exam can usually provide the information necessary to obtain an accurate diagnosis. A proficient shoulder examination and the development of an adequate differential diagnosis are important before considering advanced imaging.

SUMMARY

The shoulder complex relies upon the integrity of multiple structures for normal function. A detailed history is of paramount importance when evaluating young athletes with shoulder problems. A systematic physical examination is extremely important to guiding an accurate diagnosis. The patient's age and activity level are very important when considering the differential diagnosis. Findings obtain through history and physical examination should dictate the decision to obtain advanced imaging of the shoulder.