MRI of isolated cuboid stress fractures in adults. AJR Am J Roentgenol. 2013;201:1325-1330. [PMID: 24147421 DOI: 10.2214/ajr.13.10543]

Stress fractures of the foot - current evidence on management

Stress fractures are a consequence of repeated submaximal loads with inadequate time for recovery and biologic repair or remodelling. The foot and ankle complex (FAC) represents a common site for development of stress fractures. Whilst the overall incidence of stress fractures is low, they are prevalent in athletes and military personnel causing significant time away from sports or work. Within these populations, certain stress fractures directly correlate to specific activities. Factors that commonly influence these fractures include an acute increase in new repetitive physical activity combined with muscle fatigue, training errors or improper athletic techniques, which challenge the regenerative and remodelling capacity of bone. Depending on the site that is subject to repetitive loading, various biomechanical factors can result in abnormal concentration of forces to specific areas of the FAC resulting in stress fracture. Decreased bone marrow density (BMD) is a major biologic cause for developing stress fractures. The female athlete triad comprising eating disorder, amenorrhea and osteoporosis in competitive athletes also predisposes to stress fractures. Vitamin D deficiency is also postulated to be the cause of these fractures and may contribute to poor healing. Clinical presentation is usually with vague pain of insidious onset which worsens with activity and improves with rest. Diffuse tenderness over the affected bone is common with only a minority having any visible swelling. Plain radiographs are the first line of investigation but rarely reveal an obvious fracture. MRI scans aid in diagnosis and CT scans help in treatment and characterisation of the fracture and monitor healing. Management relates to the site of injury, which stratifies them into high or low-risk. Stress fractures of the calcaneus, cuboid and cuneiforms are classed as low-risk fractures as they usually heal with simple activity modification or short duration of non-weight bearing. Stress fractures of the navicular, talus and hallucal sesamoids are classed as high-risk fractures due to higher rates of non-union and prolonged recovery time. Metatarsal fractures can be considered high or low-risk depending on location. These warrant aggressive management, often requiring surgical intervention. Adjuncts such as vitamin D supplements, external shockwave therapy, low-intensity pulsed ultrasound therapy have been used with varying success but there remains little supportive evidence of superiority in the available literature.

The painful lateral column of the foot: from back to front

The purpose of this article is to focus attention on the abnormalities which the radiologist may encounter in patients presenting with lateral ankle or foot pain outside of the context of acute trauma. These include anterolateral impingement, subfibular impingement, subtalar instability and tarsal sinus syndrome, tarsal coalition, sural neuromas, peroneal tendon abnormalities, calcaneocuboid instability and occult cuboid fractures, and painful accessory ossicles. The expected and unexpected findings on radiographs, CT, US, and MRI are discussed.

Update on diagnosis and management of cuboid fractures

Cuboid fractures due to the particular bone anatomy and its protected location in the midfoot are rare, and they are usually associated with complex injuries of the foot. Clinical examination to diagnose these fractures should be detailed and the differential diagnosis, especially in the case of vague symptoms, should include the exclusion of all lateral foot pain causes. Conventional radiographs do not always reveal occult fractures, which can be under diagnosed especially in children. In this case, further investigation including magnetic resonance imaging or scintigraphy may be required. The treatment of these injuries depends on the particular fracture characteristics. Non-displaced isolated fractures of the cuboid bone can be effectively treated conservatively by immobilization and by avoiding weight bearing on the injured leg. In the case of shortening of the lateral column > 3 mm or articular displacement > 1 mm, surgical management of the fracture is mandatory in order to avoid negative biomechanical and functional consequences for the foot and adverse effects such as arthritis and stiffness as well as painful gait. In this review, an update on diagnosis and management of cuboid fractures is presented.

MRI of Cuboid Pulley Lesion

OBJECTIVE

The aim of this study was to describe cuboid pulley lesions and associated abnormalities on the basis of clinical findings and the results of MRI examinations of the ankle.

MATERIALS AND METHODS

A retrospective search was performed to identify patients who had a cuboid pulley lesion during a 10-year period. A cuboid pulley lesion was defined as bone marrow edema in the lateroplantar ridge of the cuboid that was shown to be wrapped by the peroneus longus tendon on MRI of the ankle. A total of 19 patients (11 men and eight women; mean age, 45.4 years) were included in the group of patients with a cuboid pulley lesion, and 38 age-and sex-matched patients without a cuboid pulley lesion were randomly selected as the control group. We reviewed medical records and assessed MRI findings that could be associated with a cuboid pulley lesion.

RESULTS

The mean (± SD) diameter of the cuboid pulley lesion was 8.9 ± 4.7 mm. Cuboid pulley lesions were associated with peroneal tenosynovitis (p < 0.001), Achilles enthesitis (p = 0.004), and a clinical diagnosis of inflammatory arthritis (p < 0.001). Eleven of the 19 patients in the group with cuboid pulley lesions had inflammatory arthritis (either rheumatoid arthritis [n = 7] or spondyloarthritis [n = 4]). The cuboid pulley lesions did not cause localized lateral foot pain and tenderness, except in one patient who had an accompanying stress fracture of the cuboid.

CONCLUSION

MRI of the ankle rarely but clearly shows cuboid pulley lesions, which themselves are not likely to cause localized pain, and cuboid pulley lesions show significant associations with peroneal tenosynovitis, Achilles enthesitis, and clinically diagnosed inflammatory arthritis.

MR imaging features of cuboid fractures in children

BACKGROUND

Cuboid fractures are rare, usually occult on initial radiographs and are often underdiagnosed. MRI is more sensitive than radiographs for detecting acute, non-displaced cuboid fractures in adults, but only case reports have described these findings in children.

OBJECTIVE

To summarize the MR and clinical features of cuboid fractures and compare MR findings with initial and follow-up radiographs in a cohort of children.

MATERIALS AND METHODS

A retrospective search for patients <18 years of age with cuboid fractures was performed during a 10-year period at a large tertiary children's hospital. Subjects with cuboid fractures reported on MRI and available clinical history were included. MR images were evaluated for fracture location, fracture morphology, percentage of marrow edema in the cuboid, subchondral disruption, and associated tendon or ligamentous injury. Initial and short-term follow-up radiographs were also reviewed when available.

RESULTS

Nineteen children ages 18 months to 17 years (mean: 9.0 years, standard deviation: 4.1 years, 63% boys) were diagnosed with cuboid fractures by MRI. Most cases of cuboid fractures are related to acute trauma (63%) but can be seen as stress fractures (16%). Most fractures (17/19, 89%) were linear in configuration. Fractures were most commonly adjacent to the tarsometatarsal joint (10/19, 52%). The degree of marrow edema was variable. Ligamentous injury was seen in two patients and tendon pathology was seen in one, all adolescents. Initial radiographs (n=10) were negative in 9 cases (90%). All available follow-up radiographs (n=12, obtained 19-42 days after MRI) demonstrated sclerosis in the region of the fracture.

CONCLUSION

MR-depicted cuboid fractures in children typically occur in isolation. The fractures were most commonly adjacent to the tarsometatarsal joint and linear in morphology. Initial radiographs were usually normal and follow-up radiographs depicted sclerosis at the site of fracture in all available cases.

Cuboid Injuries

Cuboid fractures are rare injuries. A number of different treatment methods have been proposed including plaster immobilization, open reduction, and internal fixation or external fixation. Bone grafting is commonly used to restore bony length. The majority of the current literature suggests that the loss of length of the lateral column and articular congruency are the two criteria opting for the surgical management of these fractures. Nevertheless, the exact indications and ideal management of these fractures are not established mainly due to the rarity of these injuries and the paucity of literature.

Stress fractures of the foot and ankle, part 2: site-specific etiology, imaging, and treatment, and differential diagnosis

Stress fractures of the foot and ankle are a commonly encountered problem among athletes and individuals participating in a wide range of activities. This illustrated review, the second of two parts, discusses site-specific etiological factors, imaging appearances, treatment options, and differential considerations of stress fractures of the foot and ankle. The imaging and clinical management of stress fractures of the foot and ankle are highly dependent on the specific location of the fracture, mechanical forces acting upon the injured site, vascular supply of the injured bone, and the proportion of trabecular to cortical bone at the site of injury. The most common stress fractures of the foot and ankle are low risk and include the posteromedial tibia, the calcaneus, and the second and third metatarsals. The distal fibula is a less common location, and stress fractures of the cuboid and cuneiforms are very rare, but are also considered low risk. In contrast, high-risk stress fractures are more prone to delayed union or nonunion and include the anterior tibial cortex, medial malleolus, navicular, base of the second metatarsal, proximal fifth metatarsal, hallux sesamoids, and the talus. Of these high-risk types, stress fractures of the anterior tibial cortex, the navicular, and the proximal tibial cortex may be predisposed to poor healing because of the watershed blood supply in these locations. The radiographic differential diagnosis of stress fracture includes osteoid osteoma, malignancy, and chronic osteomyelitis.

MR Imaging of the Midfoot Including Chopart and Lisfranc Joint Complexes

Following a brief description of the normal anatomy and biomechanics of the midfoot, this article focuses on MR imaging features of common osseous, tendon, and ligament abnormalities that affect the midfoot. Discussion of the anatomy and pathology affecting the Chopart and Lisfranc joint complexes, both of which play important roles in linking the midfoot to the hindfoot and the forefoot respectively, is also included.

Midfoot and Forefoot Injuries

Sports injuries of the midfoot and forefoot encompass a spectrum of osseous and soft tissue trauma. Magnetic resonance imaging serves as a primary or important supplementary diagnostic modality in evaluation of various injuries, most important of which include Lisfranc complex injury, stress fractures, and injury to the first metatarsophalangeal joint, aka "turf toe." Current technical advances in magnetic resonance and improved knowledge of regional anatomy enable thorough evaluation of the complex anatomic structures of the foot and facilitate accurate diagnosis in the setting of trauma.

The pathophysiology, diagnosis, and management of foot stress fractures

INTRODUCTION

There is an increasing prevalence of osteoporosis, and with it a rise in the diagnosis of stress fractures. Postmenopausal women are particularly at risk of stress fractures. This review article describes the pathophysiology of foot stress fractures and the latest diagnostic and treatment strategies for these common injuries.

DISCUSSION

There are numerous risk factors for stress fractures that have been identified in the literature. Reduced bone mineral density is an independent risk factor for delayed union. Prevention of stress fractures with training periodization and nutritional assessment is essential, especially in females. Diagnosis of stress fractures of the foot is based on history and diagnostic imaging, which include radiographs, ultrasound, therapeutic ultrasound, computed tomography, and bone scans; however, magnetic resonance imaging is still the gold standard. Treatment depends on the bone involved and the risk of nonunion, with high-risk fractures requiring immobilization or surgical intervention. Patients presenting with underlying bone mineral deficiency treated without surgery require a longer period of activity modification. Training rehabilitation protocols are described for those with low-risk stress fractures.

RESULTS

A useful algorithm is presented to guide the clinician in the diagnosis and management of such injuries.