Imaging appearance of entrapped periosteum within a distal femoral Salter-Harris II fracture

K-Wire-Based External Fixator for Management of Salter-Harris Type-II Distal Femur Physeal Injury

We present a case of a 16-year-old male with a Salter-Harris type II physeal slip of the distal femur managed with closed reduction and K wire and clamp-based external fixator. Knee range of motion exercises were initiated after one week. The union was observed at 10 weeks, and implant removal was done on an outpatient basis. At one year follow-up, the patient had good clinical and radiological outcomes. The K-wire-based external fixator frame is an effective fixation method for distal femur physeal slips in older children, providing favorable radiological and functional outcomes.

MRI findings of growth plate fractures of the knee: are there age- and fracture-dependent differences?

OBJECTIVE

To investigate MRI findings in children with physeal fractures of the knee with respect to age, location, and articular involvement.

METHODS

Children with physeal fractures who underwent knee MRI between 2008 and 2021 were included. Two radiologists retrospectively reviewed all examinations to determine articular involvement, findings of physeal instability (perichondral disruption, periosteal entrapment), and internal derangement (cruciate ligament injury, meniscal tear, chondromalacia). Independent samples t, Mann-Whitney U, Pearson's chi-square, and Fisher's exact tests were used to compare findings.

RESULTS

Fifty-six patients (37 boys, 19 girls; mean age: 12.2 ± 2.5 years; 32 distal femur, 24 proximal tibial fractures) included 24(43%) intraarticular fractures. Fractures were more common in the tibia than the femur (67% versus 25%, p = 0.004) and intraarticular fractures were more common in older than younger children (13.1 ± 2.0 versus 11.5 ± 2.7 years, p = 0.01), to associate with chondromalacia (46% versus 12%, p = 0.02) and undergo surgery (33% versus 10%, p = 0.04) when compared to extraarticular fractures. Perichondral disruption (n = 44, 79%) and periosteal entrapment (n = 13, 23%) did not significantly differ based on location or articular involvement (p > 0.05). At a median follow-up of 17.5 months (interquartile range: 1.25-34), 3 patients (2 intraarticular, 1 extraarticular fractures) developed osteoarthritis, osteochondral lesion, and leg-length discrepancy from growth arrest, which required additional surgery.

CONCLUSION

Intraarticular physeal fractures were more common with older children, associate with chondromalacia, and underdo surgical intervention when compared to extraarticular fractures of the knee. While MRI findings of physeal instability were common, no significant differences were found between fractures based on anatomic location or fracture pattern.

Complicated Growth Plate Fracture: Torn Metaphyseal Periosteum with Physeal Interposition

Teaching point: Displacement of torn periosteum into the growth plate is an uncommon pediatric entity following trauma – which can be seen on an MRI as low signal intensity physeal interposition on all pulse sequences, and requires open surgical reduction, as it may lead to growth plate bridging and subsequent extremity length discrepancy.

[Periosteum entrapped in growth plate cartilage in patients with epiphyseal fracture-separation: about a case]

L´incarcération de corps étranger dans le cartilage de croissance est une pathologie rare. Elle survient souvent lors d´un décollement épiphysaire. Son diagnostic est radiologique, reposant sur l'imagerie par résonnance magnétique (IRM) cérébrale. Nous rapportons ici, le cas d´une fille de 13 ans qui s´est présenté pour un genou douloureux post traumatique gauche. L´examen clinique et les radiographies standards réalisées était en faveur d´un décollement épiphysaire type 1 de Salter-Harris. Le traitement de première intention qui avait consisté en une immobilisation plâtrée pendant trois semaines était non satisfaisante. Devant cet échec thérapeutique, une IRM a été réalisée et mise en évidence une incarcération de corps étranger dans le cartilage de conjugaison. La prise en charge secondaire a été chirurgicale avec des suites opératoires simples.

Sports-Related Injuries of the Pediatric Musculoskeleton

Worldwide, more than 50 million children and adolescents participate in organized athletic programs annually. Despite the numerous health and well-being benefits, this widespread involvement also leads to acute and overuse injuries that account for millions of medical visits each year. Musculoskeletal injury in childhood may lead to growth disturbance and lifelong disability. Imaging plays a critical role in the diagnosis and management of these injuries. While radiography is sufficient for most long bone fractures, MRI is often necessary for optimal evaluation of injuries involving the radiolucent growth mechanism and articular structures. The following review will discuss the imaging features associated with many sports-related injuries unique to the pediatric musculoskeleton, specifically the lower extremity.

Update on premature physeal closure. Diagnosis and treatment

PURPOSE OF REVIEW

Premature Physeal Closure (PPC) is the most common consequence of a mostly posttraumatic, physeal injury. They are of utmost importance because they can significantly alter physeal function and lead to disorders such as limb length discrepancies and angular deformities.

RECENT FINDINGS

The type of physeal fracture has not demonstrated a solid predictive value in the formation of PPC, especially in the knee where almost any type of fracture can produce it. The detection of physeal damage with imaging tests (simple radiology and MRI) is very accurate; however, their predictive capacity to foretell which injury will generate a physeal bridge is still poor. For this reason, it is not advisable to make surgical decisions at the first medical assessment. Direct surgical management of PPC's (resection-interposition technique) has generally shown high unpredictability. Nevertheless, the latest interposition materials (chondrocytes and mesenchymal stem cells) showed promising results.

SUMMARY

PPC is an often devastating consequence of physeal injury and as such deserves further research. To date little is known about etiopathogenesis, risk factors and natural history among other aspects. Until direct surgery offers more consistent results, acute osteotomies and bone distraction for progressive correction continue to be the most widespread treatments for PPCs.

Physeal fractures of the distal femur: does a lower threshold for surgery lead to better outcomes?

Distal femur physeal fractures are known to have a high incidence of complications. Our previous reported experience (pre-2007) showed a 40% complication risk, which prompted changes in our approach. The purpose of this study was to evaluate and compare the complication rate and outcome after implementation of these changes. This is a retrospective study of children with distal femur physeal fractures treated at a level 1 pediatric trauma center between 2007 and 2016. Patient demographics, fracture patterns, treatment and outcomes including complications and its risk factors were recorded and analyzed. We compared current results with our previously reported multicenter cohort (n = 73). Patients were male in majority (57/70) with a mean age of 13 ± 4 years. Fractures were most commonly Salter-Harris Type 2 (49/70) and displaced (59/70) on presentation, although neither characteristic was associated with complications. Most patients (63/70) were treated surgically, and the overall complication incidence was 36% (25/70), including growth arrest in 20 patients. The pre-2007 cohort was statistically significantly younger (P < 0.001) and was more commonly treated nonoperatively (P < 0.001). However, there was no statistically significant difference in complication incidence between studies (36% versus 40%, respectively, P = 0.751). Despite a lower threshold for surgery for distal femur physeal fractures in the past decade, the complication rate is still high and unchanged at 40%, and presenting patients are older. There were no new prognostic factors that showed statistically significant association with subsequent complications; however, patients with high-energy injury mechanisms and greater fracture displacements did have higher complication rates. These results demonstrate the inherent high complication risk for these injuries. Level of Evidence: III.

Periosteal incarceration versus interposition adipose tissue grafting in physeal fractures: pilot study in immature rabbits

Purpose

The purpose of this study is to evaluate bar formation following physeal fracture with incarcerated periosteum or adipose tissue graft using radiographic and histological methods in an immature rabbit model.

Methods

Ten-week-old rabbits underwent induced proximal tibia physeal fractures with a contralateral sham. Fractures had periosteum (n = 5) or adipose tissue (n = 5) interposed. Radiographs were compared over time by tibial medial-lateral side difference (TMLSD)(mm), femoral-tibial angle and tibia plateau angle, and physeal bars evidence. MicroCT was performed, growth plates reconstructed, and physeal area calculated and normalized to same animal contralateral physes. Physeal disruption and chondrocyte organization were evaluated histologically.

Results

Radiographic: After 6 weeks, physeal bars formed in both periosteum (4 of 4) and fat groups (3 of 5). The periosteum group showed a significant increase in the TMLSD between immediate post-op and 10 days later (p = 0.028); but, after 6 weeks, TMLSD change was not significantly different between the three groups (p = 0.161). MicroCT: The normalized physeal area of every physis in the fat group was more than 0.9 (0.99 ± 0.06). Only half of the periosteum group was over 0.9 (0.81 ± 0.24). Histology: Physeal disruption was seen by microscopic evaluation in none of the sham group, all 4 in the periosteum group and 4 of 5 in the fat group.

Conclusions

Fat interposition may prevent, or at least delay, the onset of bars across a fractured physis compared to periosteum, but it is not completely protective.

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.

Physeal fractures about the knee

While some fractures may be managed similarly in adults and children, physeal fractures are uniquely limited to the pediatric population and require special consideration. Although physeal fractures about the knee are relatively rare, they are occurring more frequently due to increasing youth participation in sports and high-energy recreational activities. The evaluation and management of distal femoral and proximal tibial physeal fractures are similar to one another, but fractures of the tibial spine and tibial tubercle are approached somewhat differently. A thorough understanding of the pertinent developmental anatomy is critical for correlating the clinical findings with the imaging work-up, and for anticipating the most common and the most serious complications of each fracture. Diagnosis is usually made with appropriate plain radiographs with advanced imaging often used for preoperative planning. In general, fracture pattern and degree of displacement determine the need for surgical intervention and the overall outcome. While a variety of fixation techniques or constructs may be used, because of the importance of restoring physeal and articular anatomy for avoidance of growth disturbance and degenerative joint disease, respectively, achieving anatomic, rigid fixation is of greater importance than with many other fracture locations in the growing skeleton.