Imaging Pediatric Sports Injuries: Lower Extremity

Imaging of sports injuries in adolescents

Musculoskeletal injuries in adolescents tend to occur in particular locations and have distinct characteristics, as they affect an immature skeleton. Increased engagement in sports, extended training and competition periods, and early specialization in specific sports, among other factors, have contributed significantly to the rise in musculoskeletal sports injuries in adolescents. Furthermore, females show a particularly pronounced increase in sports participation, where anatomical and hormonal factors play crucial roles in the development and increased frequency of sports-related injuries. Consequently, there is a growing demand for diagnostic imaging techniques. Musculoskeletal and pediatric radiologists require a comprehensive understanding of intrinsic and extrinsic risk factors and the successive stages of skeletal development that can influence the specific characteristics of sports injuries in adolescents. These aspects are crucial for the diagnostic, prognostic, and therapeutic management of these injuries and for mitigating chronic conditions that could compromise future sports participation. This review analyzes the primary musculoskeletal injuries in adolescent athletes and highlights the pivotal role of different imaging methods in their diagnosis and management.

Bone Health in Young Athletes: a Narrative Review of the Recent Literature

PURPOSE OF REVIEW

The aim of this review is to discuss the most recent published scientific evidence regarding bone health in the pediatric athlete.

RECENT FINDINGS

Pediatric athletes commonly suffer from overuse injuries to the physes and apophyses, as well as bone stress injuries, for which magnetic resonance imaging grading of the severity of injuries may be useful in guiding return to sport. Adolescent athletes, particularly those who train indoors and during the winter season, are at risk for vitamin D deficiency, which has important implications for bone mineral density. However, the relationship between vitamin D status and traumatic fracture risk is still unclear. While the female athlete triad is a well-established condition, the current work has led to the recognition of parallel pathophysiology in male athletes, referred to as the male athlete triad. Recent evidence suggests that transdermal 17β-estradiol treatment in amenorrhoeic female athletes is an effective adjunctive treatment to improve bone mineral density in treatment of the female athlete triad. Young athletes are at risk for musculoskeletal injuries unique to the growing skeleton. Optimizing nutritional intake, particularly related to adequate vitamin D intake and prevention of the athlete triad, is critical to optimize bone health in the young athlete.

Insall-Salvati index is associated with anterior cruciate ligament tears in men: A Case-controlled study

PURPOSE

Many factors in the etiology of anterior cruciate ligament (ACL) tears, predisposing factors related to knee morphology have also been reported. This study aimed to determine whether the Insall-Salvati (IS) index, which measures patella height, is a predisposing risk factor for ACL tears.

METHODS

The IS index, patellar length (PL), and patellar tendon length (PTL) values of patients (study group) that underwent arthroscopic reconstruction for ACL tears obtained by preoperative magnetic resonance imaging (MRI) were compared with the index values in the preoperative MRIs of patients that underwent knee arthroscopy for reasons besides ACL tears. In addition, the anterior tibial translation (ATT) of both groups was also measured and compared on MRI images. The MRI findings of the subjects included in both study groups were arthroscopically confirmed.

RESULTS

The mean ages of the study group (n = 120) and control group (n = 90) were 29.1 ± 8.2 years and 31.8 ± 9.8 years, respectively. There was a statistically significant difference between the study and control groups in terms of the PL and PTL values (p = 0.016 and p = 0.001, respectively). The IS index was statistically significantly higher in the study group with ACL tears (p = 0.009). The ATT was 8.61 ± 4.68 mm in the study group and 3.80 ± 1.92 mm in the control group. The ATT results of both groups were evaluated, and it was found that the study group was significantly higher than the control group (p = 0.001).

CONCLUSIONS

As a result of our current study, we observed higher IS index values in patients with ACL tears than in patients without ACL tears. It should be kept in mind that patella alta, which is associated with a high IS index as one of the factors of knee morphology associated with ACL tears, may play a role in the etiology of ACL tears.

Apophysitis Among Male Youth Soccer Players at an Elite Soccer Academy Over 7 Seasons

Background:

Apophyseal injuries are common in children and adolescent athletes. These injuries are believed to be caused by repetitive overloading, which can create inflammatory and degenerative conditions in growing bone prominences. However, their prevalence, diagnosis, and treatment in young soccer players have been understudied.

Purpose:

To evaluate characteristics of apophyseal injuries in adolescent athletes at an elite soccer academy.

Study Design:

Case series; Level of evidence, 4.

Methods:

All apophyseal injuries between July 2008 and June 2015 were evaluated. For each injury, the authors recorded the type and location, age of the player, injury date, imaging modalities, and time absent from training/competition.

Results:

Over the 7 seasons of this study, 210 apophyseal injuries were documented, including 172 simple apophyseal injuries and 38 apophyseal avulsion fractures. The rate of apophyseal injuries was 0.35 per 1000 hours of training exposure. A total of 196 (93.3%) cases were primary injuries, and the rest (6.7%) were reinjuries. Ultrasonography was the most commonly used imaging modality for diagnosis (172 cases; 81.9%). The most common location of apophyseal injuries was the anterior inferior iliac spine (AIIS). Return to sport was faster in athletes with apophyseal injury at the ischiopubic ramus, those with simple apophyseal injuries, and younger athletes.

Conclusion:

The most common location for apophyseal injury among soccer players was the AIIS. Return to training and competition differed according to injury location, type of apophyseal injury, and age.

Pediatric Trauma

Musculoskeletal injuries of the lower limb are frequent in pediatric patients and represent the most common cause of emergency department admissions. Acute sports-related injuries commonly involve the lower extremity, as the knee and ankle are the most frequently injured parts. Physeal fractures are common injuries in children and adolescents participating in contact sports, which may lead to growth disturbances and cause limb length discrepancy. It is imperative for pediatric trauma centers to implement evidence-based multispecialty protocols for the perimanagement of the injured child, especially through the postdischarge and rehabilitation phases, in order for the child to resume active daily living.

Hip apophyseal injuries in soccer players: can MRI findings be useful to define when to return to play?

OBJECTIVE

To describe magnetic resonance imaging (MRI) findings in professional soccer players with acute apophyseal injury of the hip and to assess their relationship with return to sports.

MATERIAL AND METHODS

Adolescent soccer players with diagnosis of apophyseal injury in the anterosuperior and anteroinferior iliac spine were retrospectively evaluated between 2008 and 2016. All athletes underwent hip MRI examination within 4 days after onset of clinical complaint. Images were independently analyzed by two radiologists. Medical records were reviewed to obtain clinical data.

RESULTS

Mean displacement of the apophysis was 4.8 ± 4.6 mm. Bone edema was present in 82% of athletes and muscular edema in 41%. The mean time to return to sports was 37.3 ± 14.7 days. The difference between the measurements of the two radiologists was close to zero with agreement limits below 1.0 mm (p < 0.001). There was a significant correlation between displacement of the apophysis and return to sports, as well as between both and the presence of muscular edema. A displacement of the apophysis of 3.0 mm might serve as a parameter to predict return to sports/activity before 40 days, with a sensitivity of 92% and specificity of 96%, considering conservative physiotherapy treatment.

CONCLUSION

Displacement of the apophysis and presence of muscular edema evaluated by MRI showed a significant correlation with return to sports in athletes with acute apophyseal injuries of the anterosuperior and anteroinferior iliac spines.

Imaging of Pediatric Lower Limb Sports Injuries

The importance of physical activity during childhood and adolescence has come to light, with an increase in sports-related acute traumatic and overuse injuries as a major disadvantage. A solid understanding of the physiology of the growing skeleton, together with knowledge about age- and sex-related differences in the occurrence of acute traumatic and overuse injuries is necessary. Every musculoskeletal radiologist should also be familiar with the appearances of these injuries on different imaging modalities. This review focuses on all these aspects concerning acute traumatic and overuse injuries among children and adolescents.

Imaging of the Posttraumatic Knee in Pediatric Patients

Owing to its continuous transformation, the musculoskeletal system of pediatric patients presents some unique features with respect to both anatomy and physiology. The lesional pattern of the knee in pediatric patients is both similar to and in many aspects different from the lesional pattern in adults with knee injuries. In the case of pediatric patients, meniscal, tendinous and ligamentous lesions occur most frequently as a consequence of traumatic episodes. The purpose of the present study is to emphasize the importance of MRI examinations in pediatric patients exhibiting symptoms of knee joint injury. The imaging assessment of the extent of the lesions, which can be either simple or complex alterations, can directly influence the clinical management of these cases by appreciating the growth potential of the specific segment of immature skeleton involved.

No superiority of dextrose injections over placebo injections for Osgood-Schlatter disease: a prospective randomized double-blind study

PURPOSE

Osgood-Schlatter disease (OSD) is a traction apophysitis of the tibial tuberosity. Patellar tendinopathy and deep infrapatellar bursitis have recently been shown to contribute to pain in patients with OSD. We compared the effects of dextrose injection and saline injection.

METHODS

We performed a clinical trial from April 2012 to January 2016 and included 49 knees from 37 boys and 1 girl (mean age, 12.3 ± 1.1 years) for whom conventional conservative therapy for > 1 month was ineffective. They were randomly assigned to receive double-blind injections of 1% lidocaine (1 mL) with 20% dextrose (1 mL; dextrose group) or 1% lidocaine (1 mL) with saline (1 mL; saline group). Injections were administered monthly for 3 months by a single investigator. The Victorian Institute of Sport Assessment (VISA) score was used to evaluate anterior knee pain.

RESULTS

Overall, 43 knees were included; 6 knees were lost to follow-up. The mean pre-injection VISA scores in the dextrose and saline groups were 58.7 ± 18.3 and 63.4 ± 16.4, respectively. No significant differences were found between the two groups at any time point. The mean VISA score before injections significantly increased at the 1-month follow-up in both groups (P < .01). The injection had no adverse effects.

CONCLUSIONS

We were not able to show the efficacy of dextrose injections compared to that of saline.

LEVEL OF EVIDENCE

Randomized controlled trial. Level I.

Injuries of the adolescent girl athlete: a review of imaging findings

With the rising participation of girls in sports at both the recreational and elite levels, there has also been increased awareness of injuries common in this athlete population. Anatomic differences between boys and girls cause girl athletes to be predisposed to certain injuries. Certain behavioral patterns, such as eating disorders, also cause problems specific to girl athletes that may result in injury. Imaging plays a large role in diagnosis and ongoing management, but there has been only scant literature dedicated to the specific topic of imaging in girl athletes. The purpose of this article is to review the imaging findings and recommendations for injuries and other conditions affecting the adolescent girl athlete. This article first provides an overview of the key anatomic differences between boys and girls, including both static and dynamic factors, as well as non-anatomic differences, such as hormonal factors, and discusses how these differences contribute to the injury patterns that are seen more typically in girls. The article then reviews the imaging findings in injuries that are commonly seen in girl athletes. There is also a discussion of the "female athlete triad," which consists of osteoporosis, disordered eating, and amenorrhea, and the role of imaging in this condition.

Imaging of Sports-related Injuries of the Lower Extremity in Pediatric Patients

With increasing participation and intensity of training in youth sports in the United States, the incidence of sports-related injuries is increasing, and the types of injuries are shifting. In this article, the authors review sports injuries of the lower extremity, including both acute and overuse injuries, that are common in or specific to the pediatric population. Common traumatic injuries that occur in individuals of all ages (eg, tears of the acetabular labrum and anterior cruciate ligament) are not addressed, although these occur routinely in pediatric sports. However, some injuries that occur almost exclusively in high-level athletes (eg, athletic pubalgia) are reviewed to increase awareness and understanding of these entities among pediatric radiologists who may not be familiar with them and thus may not look for them. Injuries are described according to their location (ie, hip, knee, or foot and ankle) and pathologic process (eg, apophysitis, osteochondritis dissecans). Examples of abnormalities and normal variants of the anatomy that are often misdiagnosed are provided. The injuries reviewed represent a common and growing subset of pathologic processes about which all pediatric and musculoskeletal radiologists should be knowledgeable. Understanding physeal injury is especially important because missed diagnoses can lead to premature physeal closure and osteoarthritis. ^©RSNA, 2016.

Pediatric Elbow and Wrist Pathology Related to Sports Participation

Pediatric overuse injuries are becoming more prevalent in today's society with more children competitively playing year-round sports at a younger age. The importance of prompt diagnosis and treatment is paramount to the treatment for these injuries, second only to rest and activity modification. This article will focus on overuse injuries of the upper extremity, specifically: little league elbow, elbow osteochondritis dissecans, and gymnast wrist. It will also discuss the pathophysiology, diagnosis, imaging, and treatment of each of these entities.

Diagnostic Efficacy of 3-T MRI for Knee Injuries Using Arthroscopy as a Reference Standard: A Meta-Analysis

OBJECTIVE

The objectives of our study were to assess the evidence for the diagnostic efficacy of 3-T MRI for meniscal and anterior cruciate ligament (ACL) injuries in the knee using arthroscopy as the reference standard and to compare these results with the results of a previous meta-analysis assessing 1.5-T MRI.

MATERIALS AND METHODS

The online Cochrane Library, MEDLINE, and PubMed databases were searched using the following terms: MRI AND ((3 OR three) AND (Tesla OR T)) AND knee AND arthroscopy AND (menisc* OR ligament). Patient demographics, patient characteristics, MRI scanning details, and diagnostic results were investigated. The methodologic quality of the included studies was assessed using the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. A meta-analysis of studies using 3-T MRI was performed, and the results were compared with a previous meta-analysis of studies using 1.5-T MRI.

RESULTS

One hundred one studies were identified by the search strategy, and 13 studies were included in our review. Twelve studies were considered to have level 1b evidence, and one study was considered to have level 2b evidence. All 13 studies had high methodologic integrity and low risk of bias using the QUADAS-2 tool. The studies included 1197 patients with a mean age of 41.9 years. Ten of the 13 studies were eligible for meta-analysis. The mean sensitivity and mean specificity of 3-T MRI for knee injuries by location were as follows: medial meniscus, 0.94 (95% CI, 0.91-0.96) and 0.79 (95% CI, 0.75-0.83), respectively; lateral meniscus, 0.81 (95% CI, 0.75-0.85) and 0.87 (95% CI, 0.84-0.89); and ACL, 0.92 (95% CI, 0.83-0.96) and 0.99 (95% CI, 0.96-1.00). The specificity of 3-T MRI for injuries of the lateral meniscus was significantly lower than that of 1.5-T MRI (p = 0.0013).

CONCLUSION

This study does not provide evidence that 3-T scanners have superior diagnostic efficacy for meniscal damage and ACL integrity when compared with previous studies of 1.5-T machines.

Overuse injuries in children

There has been a substantial increase in the number of children participating in organized competitive sports, which has led to a surge in the number of both acute and overuse injuries. To prevent further complications such as limb deformity and disability, radiologists must be familiar with typical overuse injury patterns in children. Traction apophysitis, chronic physeal injury, and stress fractures are the principal overuse injuries. This article reviews overuse injuries in children with an emphasis on the role of magnetic resonance imaging in diagnosis, prognosis, and treatment.

Imaging of physeal injury: overuse

Context:

As the intensity of youth participation in athletic activities continues to rise, the number of overuse injuries has also increased. A subset of overuse injuries involves the physis, which is extremely susceptible to injury. This paper aims to review the utility of the various imaging modalities in the diagnosis and management of physeal injuries in the skeletally immature population.

Evidence Acquisition:

A search for the keywords pediatric, physis, growth plate, x-ray, computed tomography, magnetic resonance imaging, and overuse injury was performed using the PubMed database. No limits were set for the years of publication. Articles were reviewed for relevance with an emphasis on the imaging of growth plate injuries.

Study Design:

Retrospective literature review.

Level of Evidence:

Level 4.

Results:

Three major imaging modalities (radiographs, computed tomography, and magnetic resonance imaging) complement each other in the evaluation of pediatric patients with overuse injuries. However, magnetic resonance imaging is the only modality that offers direct visualization of the physis, and it also offers the best soft tissue contrast for evaluating the other periarticular structures for concomitant injury.

Conclusion:

Imaging has an important role in the diagnosis of physeal injuries, and the information it provides has a tremendous impact on the subsequent management of these patients.

Imaging of lumps and bumps in pediatric patients: an algorithm for appropriate imaging and pictorial review

Superficial lumps and bumps are a common presenting complaint in the pediatric patient population. Although encountered frequently, the path to a definitive diagnosis is not always a straightforward one. Imaging offers a valuable tool to aid in this diagnostic challenge. Radiologists must be familiar with pediatric lumps and bumps, their imaging characteristics, and the best way to further evaluate challenging clinical presentations. This will not only allow the radiologist to serve as a valuable asset to the treating physician in choosing the most appropriate imaging modality but also help in accurate diagnosis, all while ensuring the "image gently" principle. An algorithm for imaging in the pediatric patient with lumps and bumps has been presented in this article and a few example entities along with their imaging findings have also been reviewed.

Accuracy of 3-Tesla magnetic resonance imaging for the diagnosis of intra-articular knee injuries in children and teenagers

BACKGROUND

Magnetic resonance imaging (MRI) is a commonly used tool for the diagnosis of intra-articular knee pathologies. Although many studies have reported the accuracy of MRI in the adult population, fewer studies have investigated these tests in younger patients. Furthermore, these studies have shown a higher variability in both the sensitivity and the specificity of MRI for these knee injuries in this age group. Advancements in MRI technology, such as the 3-Tesla (3T) MRI magnet, have shown promising results for musculoskeletal injury diagnosis in adults. This study aims to evaluate 3 T MRI for the diagnosis of intra-articular knee pathologies in a pediatric and adolescent patient population.

METHODS

The records of 116 patients (119 knees) under the age of 20 years who underwent 3 T MRI studies of the knee and subsequent knee arthroscopy were reviewed retrospectively. The MRI report from the musculoskeletal radiology staff, the interpretation from the staff orthopedic surgeon, and the operative note dictations were compared, with a focus on meniscus and anterior cruciate ligament (ACL) pathologies. Seventeen orthopedic staff reads were not obtainable. Arthroscopy was used as the gold standard for diagnosis.

RESULTS

The average age at MRI exam was 16.0 years and at surgery was 16.2 years. Using the musculoskeletal radiologist interpretation, the sensitivity and the specificity of 3 T MRI were 81.0% and 90.9% for medial meniscus injuries, 68.8% and 93% for lateral meniscus injuries, and 97.9% and 98.6% for ACL injuries, respectively. The orthopedic surgeon's interpretation of 3 T MRI had a sensitivity and specificity of 75.7% and 92.4% for medial meniscus injuries, 69.8% and 98.3% for lateral meniscus injuries, and 100% and 98.6% for ACL injuries, respectively. Posterior horn tears had the greatest discrepancies.

CONCLUSIONS

When performed on pediatric and adolescent patients, newer 3 T MRI studies have excellent accuracy for diagnosing ACL tears. These studies also show a higher accuracy for the diagnosis of medial meniscal tears than lateral meniscal tears.

LEVEL OF EVIDENCE

Diagnostic study--Level 2.

MRI of radiographically occult ischial apophyseal avulsions

BACKGROUND

Acute avulsions of unossified ischial apophyses in children may go undetected on radiography. Therapy includes rest and rehabilitation; however, substantial displacement may require surgery.

OBJECTIVE

Our purpose is to illustrate the utility of MRI in the detection of these radiographically occult injuries in skeletally immature children.

MATERIALS AND METHODS

This retrospective study of more than 5 years included children with ischial avulsions who were evaluated with both radiography and MRI within 3 weeks of acute injury. Initially, radiographs were reviewed to identify those children with unossified ischial apophyses. Subsequently, their MRI examinations were assessed for physeal disruption, bone/soft tissue edema, periosteal/perichondrial elevation and disruption. Initial and follow-up radiographs (if available) were reviewed. Patient age, symptoms and offending activity were determined from clinical records.

RESULTS

Five children met inclusion criteria. All initial radiographs were normal. MRI showed: edema (n = 5), periosteal elevation (n = 4), periosteal/perichondrial disruption (n = 4), >5.5 mm displacement (n = 0). Follow-up radiographs in two children (2 and 2.5 months from MRI) showed osseous ischial irregularity. The apophyses remained unossified.

CONCLUSIONS

Acute unossified ischial apophyseal avulsions in children may be radiographically undetected. In the setting of correlative clinical symptoms, MRI can be used to identify these injuries and to help direct appropriate therapy.

Osteochondritis dissecans of both knees, both elbows, and the first metatarsophalangeal joint in a female soccer player

A 19-year-old female soccer player presented for evaluation of pain at the base of the right hallux after a recent sports injury. She had a history of 4 operations, 1 each at both knees and both elbows, for the treatment of osteochondritis dissecans (OCD). Examination showed tenderness to palpation and limited range of motion of the first metatarsophalangeal (MP) joint, and radiographs showed stage 4 OCD of the first metatarsal head with a detached osseous fragment. Diagnostic arthroscopy confirmed the presence of OCD, and treatment included arthrotomy, excision of the loose body, and microfracture of the defect. Evaluation at 3 months after surgery showed that the first MP joint pain and limited motion had completely resolved, and the patient returned to soccer practice. Although OCD at 1 location is diagnosed frequently in athletes, involvement of 5 different joints in the same patient is uncommon.

MRI of pediatric patients: Part 2, normal variants and abnormalities of the knee

OBJECTIVE

The purpose of this article is to discuss MRI of the pediatric knee and familiarize the reader with conditions encountered in the pediatric population. Clinical scenarios are included to convey important concepts and to orient the learner to normal variants and abnormalities of the pediatric knee. The conditions discussed include, but are not limited to, distal femoral metaphysial irregularity, isolated popliteus tendon avulsion, juvenile idiopathic arthritis, and discoid meniscus.

CONCLUSION

The knee is the joint that is most commonly imaged by MRI in children. Injury patterns and signs of other pathologic processes seen in skeletally immature patients are different from those seen in adults. Interpreting pediatric knee MRI studies may be a challenge for those unfamiliar with the evolving patterns of normal development and of the signs of conditions that are more prevalent in children. Through case scenarios, this article describes and provides images that depict conditions commonly encountered in the pediatric knee. Most of the described normal findings and abnormalities are more prevalent in the pediatric population than in adults, and a few of the conditions are, in fact, unique to pediatric patients.

Hyperosmolar dextrose injection for recalcitrant Osgood-Schlatter disease

OBJECTIVE

To examine the potential of dextrose injection versus lidocaine injection versus supervised usual care to reduce sport alteration and sport-related symptoms in adolescent athletes with Osgood-Schlatter disease.

PATIENTS AND METHODS

Girls aged 9 to 15 and boys aged 10 to 17 were randomly assigned to either therapist-supervised usual care or double-blind injection of 1% lidocaine solution with or without 12.5% dextrose. Injections were administered monthly for 3 months. All subjects were then offered dextrose injections monthly as needed. Unaltered sport (Nirschl Pain Phase Scale < 4) and asymptomatic sport (Nirschl Pain Phase Scale = 0) were the threshold goals.

RESULTS

Sixty-five knees in 54 athletes were treated. Compared with usual care at 3 months, unaltered sport was more common in both dextrose-treated (21 of 21 vs 13 of 22; P = .001) and lidocaine-treated (20 of 22 vs 13 of 22; P = .034) knees, and asymptomatic sport was more frequent in dextrose-treated knees than either lidocaine-treated (14 of 21 vs 5 of 22; P = .006) or usual-care-treated (14 of 21 vs 3 of 22; P < .001) knees. At 1 year, asymptomatic sport was more common in dextrose-treated knees than knees treated with only lidocaine (32 of 38 vs 6 of 13; P = .024) or only usual care (32 of 38 vs 2 of 14; P < .0001).

CONCLUSIONS

Our results suggest superior symptom-reduction efficacy of injection therapy over usual care in the treatment of Osgood-Schlatter disease in adolescents. A significant component of the effect seems to be associated with the dextrose component of a dextrose/lidocaine solution. Dextrose injection over the apophysis and patellar tendon origin was safe and well tolerated and resulted in more rapid and frequent achievement of unaltered sport and asymptomatic sport than usual care.