16-Detector multislice CT in the detection of stress fractures: a comparison with skeletal scintigraphy

Therapeutic ultrasound related pain threshold in elite track & field athletes with tibial bone stress injuries

OBJECTIVE

Tibial stress injuries are challenging in terms of early diagnosis, management strategy, and safe return-to-play. In the present study, pain production associated with the application of therapeutic ultrasound (TUS) was used as a primary diagnostic tool to assess tibial bone stress injuries, and the sensitivity of this procedure was compared with Magnetic Resonance Imaging (MRI).

SUBJECT AND METHODS

The study was designed as a retrospective analysis of prospectively collected data on tibial bone stress injuries in elite Track and field athletes attending the National Track and Field Athletics Centre in Thessaloniki, Greece, in the period 1995-2007. All patients underwent evaluation by TUS, and the sensitivity of the procedure was compared with MRI.

RESULTS

Four of 29 athletes showed a positive TUS examination for stress injury while MRI showed normal findings. Additionally, 5 athletes evidenced MRI findings typical of a tibial bone stress injury, while TUS evaluation was negative. Using MRI as the standard, TUS displayed a sensitivity of 79.2%.

CONCLUSION

Therapeutic ultrasound is a reproducible modality with satisfactory reliability and sensitivity related to MRI, and could represent a useful tool for clinicians to primarily assess suspected tibial bone stress injuries in high qualification Track and Field athletes.

Rib Fractures in Professional Baseball Pitchers: Mechanics, Epidemiology, and Management

Pitching is a complex kinetic chain activity requiring the transfer of energy from the lower body, through the core and trunk, and finally through the arm to generate explosive acceleration of the baseball. As a result, large forces are generated in the trunk musculature and rib attachments from the late cocking phase of pitching through deceleration. The repetitive cumulative load and high pitch velocities put professional pitchers at risk of rib stress fracture. Given the potential for a prolonged recovery course and high rate of recurrence, early recognition of rib bone stress injury is critical to optimize care. Identifying torso strength imbalances, suboptimal pitching biomechanics (such as late or inadequate pelvic rotation), as well as metabolic deficiencies that may adversely affect bone health are essential to expedite safe return to play and prevent future injury. In this review, we discuss risk factors, mechanism of injury, typical clinical presentation, diagnostic imaging findings, and propose treatment and prevention strategies for rib stress fractures in overhand pitchers.

Prophylaxis of Pain and Fractures within Feet in the Course of Osteoporosis: The Issue of Diagnosing

Background

Considering the enormous risk of fractures in the course of osteoporosis in the area of the feet, an important aspect of prophylaxis is periodic and, in special cases, ongoing monitoring of defects and deformations as well as pressure distribution. The purpose of this article is to indicate the role of the examination of posture and pressure distribution during standing, postural balance, and gait, in the prevention of fatigue fractures in the course of osteoporosis, based on the literature review and examples of patients.

Methods

The manuscript consists of two parts; it has a review-analytical character. The first part reviews the literature. The data were obtained using the MEDLINE (PubMed), as well as Cochrane and Embase databases. The database review was carried out focusing mainly on English-language publications, while taking into account the topicality of scientific and research works in the area of osteoporosis. The problem of multiaspects in the area of bone density was pointed out. Considering the above, in the second part, the authors analyzed 11 exemplary patients with osteoporosis, referring to the assessment of foot and lower limb defects using traditional posturological methods and including pedobarography to diagnostic procedures that are used in the assessment of pressure distribution, standing and moving, and an attempt to balance.

Results

Analysis of the research and scientific literature proved the lack of unambiguous diagnostic procedures of the locomotor system recommended for the prevention of fatigue fractures in the course of osteoporosis. The main diagnostic recommendations are imaging tests (most often X-ray), which are recommended in the case of specific clinical symptoms. The analysis of exemplary patients with osteoporosis showed numerous disorders in the distribution of pressure in the plantar part of the feet, which are related, among other things, with their individual defects and lower limbs.

Conclusions

Detailed posture diagnostics and gait estimation, along with the analysis of pressure distribution within the feet are a very important aspect of the prevention of structural degradation and fatigue fractures within the feet. An important postulate for further research and scientific work is the elaboration of the procedures that will serve the preventive diagnostics of the locomotor system, aimed at early detection of threats of fatigue fractures.

Conservative versus surgical treatment of 21 sports horses with osseous trauma in the proximal phalangeal sagittal groove diagnosed by low-field MRI

OBJECTIVE

To compare the outcome following conservative vs surgical management of sports horses with a diagnosis of subchondral bone trauma of the proximal aspect of the proximal phalanx (PP) by low-field MRI.

STUDY DESIGN

Retrospective case series.

ANIMALS

Twenty-one mature sports horses with evidence of high water signal within the proximal sagittal groove of the PP according to low-field MRI of the fetlock, with no definitive radiographic evidence of fracture.

METHODS

Medical records (2010-2017) of horses admitted to 2 referral hospitals were reviewed. Historical, clinical, radiographic, and MRI findings and treatment choice were recorded. Conservative management consisted of confinement to a stall followed by gradual reintroduction to exercise. Surgical management consisted of cortical screw fixation across the proximal aspect of the PP. Long-term outcome was determined by telephone questionnaire or by clinical records review. Fisher's exact test was used to compare outcome between the 2 treatment groups.

RESULTS

Follow-up was available in 17 of 21 horses in the study, including 8 horses treated conservatively and 9 treated surgically. No difference in outcome was detected in this study; 4 of 8 horses were sound after conservative management, and 5 of 9 horses were sound after surgery (P > .99).

CONCLUSION

Approximately half of the horses that had a diagnosis of osseous trauma within the proximal aspect of PP returned to athletic activity, regardless of conservative or surgical management.

CLINICAL SIGNIFICANCE

The prognosis for return to athletic functions in horses with osseous trauma within the proximal aspect of the PP is guarded.

ACR Appropriateness Criteria® Stress (Fatigue/Insufficiency) Fracture, Including Sacrum, Excluding Other Vertebrae

Stress fractures, including both fatigue and insufficiency types, are frequently encountered in clinical practice as a source of pain in both athletes and patients with predisposing conditions. Radiography is the imaging modality of choice for baseline diagnosis. MRI has greatly improved our ability to diagnose radiographically occult stress fractures. Tc-99m bone scan and CT may also be useful as diagnostic tools. Although fatigue and insufficiency fractures can be self-limited and go onto healing even without diagnosis, there is usually value in initiating prompt therapeutic measures as incomplete stress fractures have the potential of progressing to completion and requiring more invasive treatment or delay in return to activity. This is particularly important in the setting of stress fractures of the femoral neck. Accuracy in the identification of these injuries is also relevant because the differential diagnosis includes entities that would otherwise be treated significantly different (ie, osteoid osteoma, osteomyelitis, and metastasis). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Stress Fractures of the Calcaneus Diagnosed by Sonography: Report of 8 Cases

We present a retrospective review of 8 patients (6 women and 2 men, with an age range of 46-80 years; mean age, 60.2 years) in whom sonography was used to diagnose a calcaneal stress fracture. Sonography was performed because of a clinical suspicion of soft tissue injuries. Two patients were first assessed by standard radiography; for the remaining patients, sonography was the first imaging technique used. Patients were subsequently examined by magnetic resonance imaging, except for 1 patient in whom the diagnosis was made only on a clinical-sonographic correlation. On sonography, there was thickening of the periosteum and subcutaneous edema in all patients; a calcified bone callus was evident in none of the 8 patients. Cortical irregularities were found in 6 of 8 patients. Color Doppler imaging showed local hypervascular changes of the periosteum in all patients. Sonography, together with clinical findings, can be used to diagnose a calcaneal stress fracture. We suggest that sonologists should include a calcaneal stress fracture in their differential diagnosis in cases of mechanical hind foot pain. They must also include, as a part of every sonographic examination of the ankle, an examination of the calcaneus and be aware of the sonographic appearance of stress fractures. If the diagnosis is still uncertain after the sonographic examination, magnetic resonance imaging should be prescribed.

Diagnostic Accuracy of Various Imaging Modalities for Suspected Lower Extremity Stress Fractures: A Systematic Review With Evidence-Based Recommendations for Clinical Practice

BACKGROUND

The literature is filled with conflicting findings regarding diagnostic accuracy and protocols for imaging suspected lower extremity stress fractures. The absence of systematic reviews on this topic has limited the development of evidence-based recommendations for appropriate imaging protocols in cases of suspected lower extremity stress fractures.

PURPOSE

To determine the diagnostic accuracy statistics of imaging modalities used to diagnose lower extremity stress fractures and to synthesize evidence-based recommendations for clinical practice.

STUDY DESIGN

Systematic review.

METHODS

A generic search strategy for published studies was performed using multiple databases. A study was eligible for inclusion if it met all of the following criteria: (1) at least 1 diagnostic imaging modality was studied, (2) at least 1 radiological reference standard was used, (3) the study reported or allowed computation of diagnostic accuracy statistics (sensitivity, specificity, positive likelihood ratio, negative likelihood ratio), (4) a full-text version was available, (5) the article was written in English, and (6) the study included lower extremity stress fractures. Studies that examined asymptomatic individuals or patients with fractures due to disease or pharmacologic intervention were excluded.

RESULTS

Reported sensitivity and specificity (95% CI) were as follows: For conventional radiography, sensitivity ranged from 12% (0%-29%) to 56% (39%-72%) and specificity ranged from 88% (55%-100%) to 96% (87%-100%). For nuclear scintigraphy (NS), sensitivity ranged from 50% (23%-77%) to 97% (90%-100%) and specificity from 33% (12%-53%) to 98% (93%-100%). For magnetic resonance imaging (MRI), sensitivity ranged from 68% (45%-90%) to 99% (95%-100%) and specificity from 4% (0%-11%) to 97% (88%-100%). For computed tomography, sensitivity ranged from 32% (8%-57%) to 38% (16%-59%) and specificity from 88% (55%-100%) to 98% (91%-100%). For ultrasound, sensitivity ranged from 43% (26%-61%) to 99% (95%-100%) and specificity from 13% (0%-45%) to 79% (61%-96%).

CONCLUSION

MRI was identified as the most sensitive and specific imaging test for diagnosing stress fractures of the lower extremity. When MRI is available, NS is not recommended because of its low specificity, high dosage of ionizing radiation, and other limitations. Conventional radiographs are likely to result in false negatives upon initial presentation, particularly in the early stages of stress fracture, and in some cases may not reveal an existing stress fracture at any time. A diagnostic imaging algorithm was developed with specific recommendations for cost-efficient imaging of low-risk and high-risk suspected stress fractures.

Stress fracture of the pelvis and lower limbs including atypical femoral fractures-a review

Stress fractures, that is fatigue and insufficiency fractures, of the pelvis and lower limb come in many guises. Most doctors are familiar with typical sacral, tibial or metatarsal stress fractures. However, even common and typical presentations can pose diagnostic difficulties especially early after the onset of clinical symptoms. This article reviews the aetiology and pathophysiology of stress fractures and their reflection in the imaging appearances. The role of varying imaging modalities is laid out and typical findings are demonstrated. Emphasis is given to sometimes less well-appreciated fractures, which might be missed and can have devastating consequences for longer term patient outcomes. In particular, atypical femoral shaft fractures and their relationship to bisphosphonates are discussed. Migrating bone marrow oedema syndrome, transient osteoporosis and spontaneous osteonecrosis are reviewed as manifestations of stress fractures. Radiotherapy-related stress fractures are examined in more detail. An overview of typical sites of stress fractures in the pelvis and lower limbs and their particular clinical relevance concludes this review.

Teaching Points

• Stress fractures indicate bone fatigue or insufficiency or a combination of these.

• Radiographic visibility of stress fractures is delayed by 2 to 3 weeks.

• MRI is the most sensitive and specific modality for stress fractures.

• Stress fractures are often multiple; the underlying cause should be evaluated.

• Infratrochanteric lateral femoral fractures suggest an atypical femoral fracture (AFF); endocrinologist referral is advisable.

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.

Stress fractures of the pelvis and legs in athletes: a review

CONTEXT

Stress fractures are common injuries in athletes, often difficult to diagnose. A stress fracture is a fatigue-induced fracture of bone caused by repeated applications of stress over time.

EVIDENCE ACQUISITION

PubMed articles published from 1974 to January 2012.

RESULTS

Intrinsic and extrinsic factors may predict the risk of stress fractures in athletes, including bone health, training, nutrition, and biomechanical factors. Based on their location, stress fractures may be categorized as low- or high-risk, depending on the likelihood of the injury developing into a complete fracture. Treatment for these injuries varies substantially and must account for the risk level of the fractured bone, the stage of fracture development, and the needs of the patient. High-risk fractures include the anterior tibia, lateral femoral neck, patella, medial malleolus, and femoral head. Low-risk fractures include the posteromedial tibia, fibula, medial femoral shaft, and pelvis. Magnetic resonance is the imaging test of choice for diagnosis.

CONCLUSIONS

These injuries can lead to substantial lost time from participation. Treatment will vary by fracture location, but most stress fractures will heal with rest and modified weightbearing. Some may require more aggressive intervention, such as prolonged nonweightbearing movement or surgery. Contributing factors should also be addressed prior to return to sports.

The pathophysiology, diagnosis, and management of stress fractures in postmenopausal women

INTRODUCTION

Increasing numbers of elderly individuals are now participating in marathons. With increased participation in running, there has been an increase in the diagnosis of stress fractures in the elderly population. Postmenopausal women are particularly at risk due to osteoporosis.

DISCUSSION

There are numerous risk factors for stress fractures in the literature that need to be addressed to reduce the risk of injury and recurrence in postmenopausal women. Diagnostic tests include plain radiograph, ultrasound, therapeutic ultrasound, computed tomography scan, and isotope bone scans; however, magnetic resonance imaging remains the gold standard. Treatment is based on risk stratification, with high-risk fractures managed aggressively with either non-weightbearing or surgical intervention. Although exercise is prescribed as a well-recognized treatment modality of poor bone density, balance is essential to avoid precipitating stress fractures.

CONCLUSION

Optimal exercise programs should balance the beneficial effect of increasing bone mineral density through exercise with the detrimental effect of stress fractures. A useful algorithm is presented in this article to guide the clinician in the diagnosis and management of appropriate investigations and management of such injuries. This review article describes the pathophysiology and provides a review of the literature to determine the latest diagnostic and treatment strategies for this unique population.

Modern imaging of the hand, wrist, and forearm

A review of the current state of the relevant diagnostic imaging technologies and methods and their clinical application in imaging common conditions of the hand, wrist, and forearm is presented. Evolving and future imaging technologies are also considered.

Stress fractures in the lower extremity. The importance of increasing awareness amongst radiologists

Stress fractures are fatigue injuries of bone usually caused by changes in training regimen in the population of military recruits and both professional and recreational athletes. Raised levels of sporting activity in today's population and refined imaging technologies have caused a rise in reported incidence of stress fractures in the past decades, now making up more than 10% of cases in a typical sports medicine practice. Background information (including etiology, epidemiology, clinical presentation and treatment and prevention) as well as state of the art imaging of stress fractures will be discussed to increase awareness amongst radiologists, providing the tools to play an important role in diagnosis and prognosis of stress fractures. Specific fracture sites in the lower extremity will be addressed, covering the far majority of stress fracture incidence. Proper communication between treating physician, physical therapist and radiologist is needed to obtain a high index of suspicion for this easily overlooked entity. Radiographs are not reliable for detection of stress fractures and radiologists should not falsely be comforted by them, which could result in delayed diagnosis and possibly permanent consequences for the patient. Although radiographs are mandatory to rule out differentials, they should be followed through when negative, preferably by magnetic resonance imaging (MRI), as this technique has proven to be superior to bone scintigraphy. CT can be beneficial in a limited number of patients, but should not be used routinely.