Treatment of Length-Unstable Pediatric Femur Fractures in Children Aged 5 to 11 years: A Focused Review.

Pediatric femur fractures in children aged 5 to 11 years are typically classified as length-stable versus length-unstable. For length-stable fracture patterns, there is frequent consensus among pediatric orthopaedic specialists regarding the appropriateness of flexible intramedullary nails, submuscular plates (SMP), or lateral-entry rigid intramedullary nails (LE-RIMN). With length-unstable fracture patterns, however, the decision is more complex. Age, weight, fracture pattern, fracture location, surgical technique, surgeon experience, several implant-specific details, and additional factors are all important when choosing between flexible intramedullary nail, SMP, and LE-RIMN. These familiar methods of fixation may all be supported by conflicting and sometimes heterogeneous data. When planning to treat length-unstable fractures in young children, surgeons should understand evidence-based details associated with each implant and how each patient-specific scenario affects perioperative decisions.

Controversies in the Management of Pediatric Musculoskeletal Infections: An International Viewpoint.

Pediatric musculoskeletal infections (MSIs) are a major contributor to the global burden of musculoskeletal disease in children and young adults. If untreated, or treated inappropriately or inadequately, pediatric bone and joint infections can be fatal or result in morbidity that causes significant functional disabilities to the patient and economic burden to the family and the community at large. The past decade has witnessed many advances in this field with respect to early diagnosis, management, and prevention of complications. It is important to discuss the current controversies in the management of pediatric MSIs with an international perspective. This discussion should include the controversies associated with the early diagnosis and identification of pediatric MSI in diverse settings; the controversies involved in the nonsurgical and surgical management of acute pediatric MSIs; and the controversies associated with the management of sequelae of pediatric MSI.

Decision-making for pediatric cervical spine imaging after blunt trauma: Investigating team dynamics in the emergency department.

Objective: Cervical spine imaging decision-making for pediatric traumas is complex and multidisciplinary. Implementing a risk assessment tool has the potential to reduce variation in these decisions and unnecessary radiation exposure for pediatric patients. We sought to determine how emergency department-trauma team dynamics may affect implementation of such a tool. Methods: We interviewed (pediatric and general emergency physicians, trauma surgeons, neurosurgeons, orthopedic surgeons and ED nurses at 21 hospitals to ascertain how team dynamics affect the pediatric cervical spine imaging decision-making process. Data were coded following a framework-driven deductive coding process and thematic analysis was used. Results: Forty-eight physicians, advanced practice providers, and nurses from 21 hospitals (inclusive of three US regions, trauma levels I-III, and serving towns/cities of various population sizes) were interviewed. Overall, emergency physicians and trauma surgeons indicate being generally responsible for pediatric cervical spine imaging decisions. Conflict often occurs between these specialties due to differential weighting of concerns for missing an injury versus avoiding radiation exposure. Participants described a lack of trust and unclear roles regarding ownership for the final imaging decision. Nurses commonly described low psychological safety that prohibits them from participating in the decision-making process. Conclusions: Implementation of a standardized risk assessment tool for cervical spine trauma imaging decisions must consider perspectives of both emergency medicine and trauma. Policies to define appropriate use of standardized tools within this team environment should be developed.

Treatment of Pediatric Femoral Shaft Fractures.

Diaphyseal femur fractures are common in pediatric orthopaedic settings. A patient-specific treatment plan incorporates several factors, including age, weight, fracture pattern, associated injuries, and social considerations. Nonaccidental trauma should be considered in children younger than 3 years. In general, young children are treated with noninvasive immobilization (Pavlik harness or early hip spica casting) while school-aged children are treated with internal fixation. Internal fixation options include flexible intramedullary nails, rigid locked intramedullary nails, and plate osteosynthesis. Flexible intramedullary nails have the best outcomes in children of appropriate weight, aged 5 to 11 years, with stable fracture patterns. Lateral-entry rigid intramedullary nails have been designed for use in older children. External fixation is usually reserved for complex scenarios. Regarding all treatment methods, surgeons should be aware of several technical factors necessary to optimize outcomes.

Vascular Safe Zone During Percutaneous Pinning of the Distal Femur.

PURPOSE: During percutaneous pinning of the pediatric distal femur, iatrogenic vascular damage in the medial thigh is a frequent concern. The proximity of a proximal-medial pin to these vessels has never been studied in children. This study describes a radiologic vascular safe zone that is easily visualized during surgery (wherein the superficial femoral vessels are safely posterior). METHODS: Patients ≤16 years old with magnetic resonance imaging of one or both femora between 2005 and 2020 were retrospectively reviewed. The "at-risk level" (ARL) was defined as the distal-most axial image with a femoral vessel anterior to the posterior condylar axis. A standardized retrograde lateral-to-medial pin was templated. A correlation matrix and least squares regression identified age and physeal width (PW) as ideal independent variables. A vascular safe zone above the medial femoral condyle (MFC) was modeled as a multiple of PW (i.e. x*PW) and needed to satisfy 3 age-dependent criteria: (1) at the ARL, the pin is medial to the vessels, (2) the pin exits the medial thigh before the ARL, and (3) the chosen "vascular safe zone" (x*PW) is always distal to the ARL. RESULTS: Forty-three patients averaging 7.1±3.9 (0.3-16) years old were included. Intra-Class correlation coefficients were excellent (0.92-0.98). All measurements strongly correlated with age ( r =0.76-0.92, P <0.001) and PW ( r =0.82-0.93, P <0.001). All patients satisfied criteria 1. Criteria 2 was satisfied in all patients ≥6 years old, 86% of children 4-5, and only 18% of children ≤3. In children >3 years old, the largest safe zone that satisfied criteria 3 was 2×PW. On average, the ARL was 2.5×PW (99% CI 2.3-2.7) above the MFC. The average ARL in children ≥6 years old was significantly higher than 2×PW (162 mm vs. 120 mm, P <0.001). CONCLUSION: During passage of a distal femur pin into the medial thigh, children ≥6 years old have a vascular safe zone that extends 2×PW proximal to the MFC. Surgeons should be cautious with medial pin placement in children 4-5 years old and, if possible, avoid this technique in children ≤3. LEVEL OF EVIDENCE: IV.

The Health & Economic Disparities of Congenital Musculoskeletal Disease Worldwide: An Analysis of 25 Years (1992-2017).

Background: Large disparities exist in congenital musculoskeletal disease burden worldwide. The purpose of this study is to examine and quantify the health and economic disparities of congenital musculoskeletal disease by country income level from 1992 to 2017. Methods: The Global Burden of Disease database was queried for information on disease burden attributed to "congenital musculoskeletal and limb anomalies" from 1992 to 2017. Gross national income per capita was extracted from the World Bank website. Nonparametric Kruskal-Wallis tests were used to compare morbidity and mortality across years and income levels. The number of avertable DALYs was converted to an economic disparity using the human-capital and value of a statistical life approach. Results: From 1992 to 2017, a significant decrease in deaths/100 000 was observed only in upper-middle and high income countries. Northern Africa, the Middle East, and Eastern Europe were disproportionately affected. If the burden of disease in low- and middle- income countries (LMICs) was equivalent to that in high income countries (HICs), 10% of all DALYs and 70% of all deaths attributable to congenital musculoskeletal disease in LMICs could be averted. This equates to an economic disparity of about $2 billion to $3 billion (in 2020 $USD). Conclusion: Considerable inequity exists in the burden of congenital musculoskeletal disease worldwide and there has been no change over the last 25 years in total disease burden and geographical distribution. By reducing the disease burden in LMICs to rates found in HICs, a large proportion of the health and economic consequences could be averted.

Current Concepts in the Treatment of Lateral Condyle Fractures in Children.

Lateral condyle fractures of the humerus are the second most common fracture about the elbow in children. The injury typically occurs as a result of a varus- or valgus-applied force to the forearm with the elbow in extension. Plain radiographs are sufficient in making the diagnosis; however, an elbow arthrogram permits optimal visualization of the articular surface in minimally displaced fractures. Traditionally, nonsurgical management is indicated for fractures with ≤2 mm of displacement and a congruent articular surface. Closed reduction and percutaneous pinning is performed for fractures with >2 mm of displacement with an intact cartilaginous hinge at the articular surface. Open reduction and internal fixation is often necessary for fractures with ≥4 mm of displacement or if there is articular incongruity. Complications include malunion, delayed presentation, fishtail deformity, lateral spurring, and growth arrest. Evolving management concepts include relative indications for surgical management, the optimal pin configuration, and the use of cannulated screw and bioresorbable fixation.

Intramedullary Fixation of Both Bone Forearm Fractures in Children and Adolescents: Healing Correlates With Development of the Olecranon Apophysis.

BACKGROUND: The purpose of this study was to determine whether healing of both bone forearm (BBFA) fractures in children and adolescents is associated with the stage of the olecranon apophysis development as described by the Diméglio modification of the Sauvegrain method. METHODS: Records were reviewed from 2 children's hospitals from 1997 to 2008 to identify all patients younger than 18 years of age who had BBFA fractures treated with intramedullary nail fixation. Sixty-three patients were identified meeting inclusion and exclusion criteria. The stage of the olecranon apophysis was noted on the lateral radiograph at the time of the injury. Data were statistically analyzed to assess the olecranon stage at which the increased rate of delayed union becomes more prevalent using the receiver operating characteristic curve. Time to union, complications, and need for reoperation were recorded for each group. RESULTS: One thousand three hundred ninety-eight patient records were reviewed with 63 patients meeting the inclusion criteria. Using a receiver operating characteristic curve, a cutoff of olecranon stage > 3 (stages 4 to 7) was a significant predictor of the increased rate of delayed union time compared with olecranon stages 0 to 3 (P=0.004). Non-healing-related complication rates for each group were 2/28 (7.1%) for olecranon stages and 0 to 3 and 6/35 (17.1%) for olecranon stages 4 to 7. CONCLUSIONS: The rate of delayed union for BBFA fractures that have been treated with intramedullary nail fixation is increased in children with more mature olecranon apophyses as compared with those with younger olecranon stages. We propose the use of the stage of olecranon apophysis development when choosing the surgical approach and implant for when treating operative BBFA fractures in children. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Hoverboard injuries in children and adolescents: results of a multicenter study.

With the increasing popularity of hoverboards in recent years, multiple centers have noted associated orthopaedic injuries of riders. We report the results of a multi-center study regarding hoverboard injuries in children and adolescents. who presented with extremity fractures while riding hoverboards to 12 paediatric orthopaedic centers during a 2-month period were included in the study. Circumstances of the injury, location, severity, associated injuries, and the required treatment were recorded and analysed using descriptive analysis to report the most common injuries. Between-group differences in injury location were examined using chi-squared statistics among (1) children versus adolescents and (2) males versus females. Seventy-eight patients (M/F ratio: 1.8) with average age of 11 ± 2.4 years were included in the study. Of the 78 documented injuries, upper extremity fractures were the most common (84.6%) and the most frequent fracture location overall was at the distal radius and ulna (52.6%), while ankle fractures comprised most of the lower extremity fractures (66.6%). Majority of the distal radius fractures (58.3%) and ankle fractures (62.5%) were treated with immobilization only. Seventeen displaced distal radius fractures and three displaced ankle fractures were treated with closed reduction in the majority of cases (94.1% versus 66.7%, respectively). The distal radius and ulna are the most common fracture location. Use of appropriate protective gear such as wrist guards, as well as adult supervision, may help mitigate the injuries associated with the use of this device; however, further studies are necessary to demonstrate the real effectiveness of these preventions.

Variation Among Pediatric Orthopaedic Surgeons When Treating Medial Epicondyle Fractures.

BACKGROUND: Medial epicondyle fractures are a common pediatric and adolescent injury accounting for 11% to 20% of elbow fractures in this population. This purpose of this study was to determine the variability among pediatric orthopaedic surgeons when treating pediatric medial epicondyle fractures. METHODS: A discrete choice experiment was conducted to determine which patient and injury attributes influence the management of medial epicondyle fractures by pediatric orthopaedic surgeons. A convenience sample of 13 pediatric orthopaedic surgeons reviewed 60 case vignettes of medial epicondyle fractures that included elbow radiographs and patient/injury characteristics. Displacement was incorporated into the study model as a fixed effect. Surgeons were queried if they would treat the injury with immobilization alone or open reduction and internal fixation (ORIF). Statistical analysis was performed using a mixed effect regression model. In addition, surgeons filled out a demographic questionnaire and a risk assessment to determine if these factors affected clinical decision-making. RESULTS: Elbow dislocation and fracture displacement were the only attributes that significantly influenced surgeons to perform surgery (P<0.05). The presence of an elbow dislocation had the largest impact on surgeons when choosing operative care (ß=-0.14; P=0.02). In addition, for every 1 mm increase in displacement, surgeons tended to favor ORIF by a factor of 0.09 (P<0.01). Sex, mechanism of injury, and sport participation did not influence decision-making. In total, 54% of the surgeons demonstrated a preference for ORIF for the included scenarios. On the basis of the personality Likert scale, participants were neither high-risk takers nor extremely risk adverse with an average-risk score of 2.24. Participant demographics did not influence decision-making. CONCLUSIONS: There is substantial variation among pediatric orthopaedic surgeons when treating medial epicondyle fractures. The decision to operate is significantly based on the degree of fracture displacement and if there is a concomitant elbow dislocation. There is no standardization regarding how to treat medial epicondyle fractures and better treatment algorithms are needed to provide better patient outcomes. LEVEL OF EVIDENCE: Level V.

Variation Among Pediatric Orthopaedic Surgeons When Diagnosing and Treating Pediatric and Adolescent Distal Radius Fractures.

BACKGROUND: Distal radius fractures are the most common injury in the pediatric population. The purpose of this study was to determine the variation among pediatric orthopaedic surgeons when diagnosing and treating distal radius fractures. METHODS: Nine pediatric orthopaedic surgeons reviewed 100 sets of wrist radiographs and were asked to describe the fracture, prescribe the type of treatment and length of immobilization, and determine the next follow-up visit. κ statistics were performed to assess the agreement with the chance agreement removed. RESULTS: Only fair agreement was present when diagnosing and classifying the distal radius fractures (κ=0.379). There was poor agreement regarding the type of treatment that would be recommended (κ=0.059). There was no agreement regarding the length of immobilization (κ=-0.004).Poor agreement was also present regarding when the first follow-up visit should occur (κ=0.088), whether or not new radiographs should be obtained at the first follow-up visit (κ=0.133), and if radiographs were necessary at the final follow-up visit (κ=0.163). Surgeons had fair agreement regarding stability of the fracture (κ=0.320).A subgroup analysis comparing various traits of the treatment immobilization showed providers only had a slight level of agreement on whether splint or cast immobilization should be used (κ=0.072). There was poor agreement regarding whether long-arm or short-arm immobilization should be prescribed (κ=-0.067).Twenty-three of the 100 radiographs were diagnosed as a torus/buckle fracture by all 9 surgeons. κ analysis performed on all the treatment and management questions showed that each query had poor agreement. CONCLUSIONS: The interobserver reliability of diagnosing pediatric distal radius fractures showed only fair agreement. This study demonstrates that there is no standardization regarding how to treat these fractures and the length of immobilization required for proper fracture healing. Better classification systems of distal radius fractures are needed that standardize the treatment of these injuries. LEVEL OF EVIDENCE: Level II.

Oblique Lateral Closing-Wedge Osteotomy for Cubitus Varus in Skeletally Immature Patients.

BACKGROUND: We perform an oblique lateral closing-wedge osteotomy of the distal end of the humerus to correct cubitus varus deformity in children. This deformity is often the consequence of undertreatment, malreduction, or malunion of supracondylar humeral fractures1. Although standard arcs of motion may be altered, cosmesis was traditionally considered a primary surgical indication. However, uncorrected cubitus varus leads to posterolateral rotatory instability of the elbow (PLRI)2, lateral condylar fractures3, snapping medial triceps, and ulnar nerve instability4. A contemporary understanding of these delayed sequelae has expanded our current indications. Detailed parameters predictive of late sequelae are needed to further specify surgical indications. DESCRIPTION: We remove an oblique lateral closing wedge from the distal end of the humerus via a standard lateral approach. The osteotomy is angled away from the varus joint line such that lateral cortices after reduction lack prominence. Kirschner wires provide adequate fixation in young patients. In older children, extension is simultaneously corrected, and fragments are stabilized via plate osteosynthesis. ALTERNATIVES: Patients who decline surgery are counseled regarding risks of delaying treatment until symptoms are present. PLRI manifests as lateral elbow pain or instability while rising from a chair. Once symptomatic, the lateral ulnar collateral ligament (LUCL) is irreversibly attenuated and morphologic changes in the ulnohumeral joint necessitate more extensive surgery to include distal humeral osteotomy, LUCL reconstruction, and possibly ulnar nerve transposition5. Alternative osteotomy techniques are described and categorized as simple lateral closing wedge, step-cut6-9, dome, 3-dimensional10, or distraction osteogenesis. Simple closing-wedge osteotomies include a distal cut parallel to the joint line and retain a problematic lateral prominence (if the medial cortex is intact or the distal end of the humerus is not translated medially)11,12. Step-cut osteotomies theoretically minimize this lateral prominence while enhancing inherent stability. However, these additional cuts mandate wide surgical exposure despite similar outcomes13. Three-dimensional planning employs computed tomography to create expensive anatomic cutting guides that address varus, extension, and internal rotation. However, residual internal rotation is generally well tolerated, derotation is associated with loss of fixation, and the extension deformity will successfully remodel in patients who are <10 years old14. We employ 3-dimensional planning in skeletally mature patients with complex deformity and no remodeling potential. RATIONALE: The oblique lateral closing wedge is ideal for skeletally immature patients because it is simple, reproducible, and efficient. It avoids the lateral prominence without increasing complexity or complications.

Pediatric Polytrauma: What Is the Role of Damage Control Orthopaedics in the Pediatric Population?

Severe pediatric trauma can be complicated for clinicians to manage because it is unusual and behaves somewhat differently from severe trauma in adults. Damage control orthopaedics is a philosophy that has gained traction in the past 30 years and has become standard in unstable adult trauma patients. Studies have failed to demonstrate clear utility for this approach in pediatric patients. Clinicians should understand the concepts of early total care and damage control orthopaedics for the patient with polytrauma, the physiologic factors associated with trauma in both children and adults who sustain severe trauma, and the role of early total care versus damage control orthopaedics in the treatment of the pediatric patient with polytrauma.

Challenges in Pediatric Trauma: What We All Need to Know About Diaphyseal Forearm Fractures.

Diaphyseal fractures of the radius and ulna are common injuries in children and often result from a fall on an outstretched hand. Fractures are classified by completeness, angular and rotational deformity, and displacement. The goal of management is to correct the deformity to the anatomic position or within acceptable alignment parameters as defined in the literature. This is primarily achieved by closed reduction and immobilization. Greenstick fractures are reduced by rotation of the palm toward the apex of the deformity. Complete fractures are reduced with sustained traction and manipulation. All fractures are immobilized in a cast, applied with the proper molding technique to ensure adequate stabilization, and maintained until healing is evident. Follow-up radiographs should be obtained weekly during the first 3 weeks after reduction to assess loss of reduction. Generally, postreduction malalignment greater than 20° is unacceptable, but these parameters vary based on age, fracture pattern, and the location and plane of angulation. Surgical intervention, with intramedullary nailing or plate fixation, is indicated for open fractures, for those with substantial soft-tissue injury, and when acceptable alignment cannot be achieved or maintained. Successful outcomes are seen in most forearm fractures in children, based on bone healing and restoration of functional forearm range of motion.

Staying Out of Trouble: Complications of Supracondylar Humerus Fractures.

Supracondylar fractures are among the most common fractures in children that require surgery. These fractures are also associated with some of the most serious complications of all fractures seen in children. Timely recognition and careful management can mitigate the potentially poor outcomes of these complications. Pin-site irritation and superficial infections are the most common complications seen. Cubitus varus remains another common complication, even with the use of closed reduction and pinning for management of most displaced fractures. Neurapraxias are seen in almost 10% of patients, with most resolving spontaneously. The worst complications are those that may be catastrophic for patients, causing substantial loss of function or even amputation of the limb; for example, vascular injury and compartment syndrome. Diagnosis and management of these complications should focus on strategies to ensure the best possible outcomes.

Fracture Remodeling in Children: Which Fractures Remodel and Which Do Not?

Children have the capacity to remodel fractures because of their active physis and periosteum. Orthopaedic surgeons should be aware of the general guidelines that injuries in younger children, children with less displaced fractures, and children with injuries closer to the growth plate are likely to remodel better than in older children with injuries more distant from the growth plate and with more initial deformity. It is also important to recognize that deformity in the plane of motion is generally better tolerated than deformity outside the plane of motion. Rotational malalignment tends to remodel poorly if at all. When evaluating an injury, the physician should consider the growth potential of the physes in the area local to the injury and their likely contribution to the remodeling and healing process when deciding what management is right and what reduction is acceptable.

Treatment of Closed Femoral Shaft Fractures in Children Aged 6 to 10.

BACKGROUND: Management of pediatric femoral shaft fractures remains controversial, particularly in children between the ages of 6 and 10. In the current push toward cost containment, hospital type, and surgeon subspecialization have emerged as important factors influencing this treatment decision. Thus, in the present study, we use a nationwide pediatric inpatient database to compare the: (a) incidence; (b) demographic characteristics; (c) hospital costs; (d) length of stay; and (e) treatment method of pediatric closed femoral shaft fractures admitted to general versus children's hospitals. METHODS: The Kids' Inpatient Database (KID) was queried for all patients aged 6 to 10 who sustained a closed femoral shaft fracture in 2009 or 2012, and patient records were stratified into children's hospitals and general hospitals. Primary outcome measures included method of treatment, total hospital costs, and length of stay. Student/Welch t testing and χ analysis were utilized to compare continuous and categorical outcomes, respectively, between hospital types. RESULTS: The total incidence of closed femoral shaft fractures decreased between 2009 and 2012 (1919 to 1581 patients; P=0.020), as did the proportion of patients treated in children's hospitals (58.6% to 32.3%; P<0.001). In addition, patients treated at general hospitals were more likely to receive open reduction with internal fixation (45.3% vs. 41.1%) or external fixation (4.1% vs. 2.3%), and less likely to be managed with closed reduction with internal fixation (32.0% vs. 39.7%) than those treated at children's hospitals (P<0.001 for all). CONCLUSIONS: The present study demonstrates a decrease in the incidence of closed femoral shaft fractures in 6- to 10-year old patients from 2009 to 2012, as well as decreased definitive management in children's hospitals and increased selection of operative treatment. In addition, treatment in a nonchildren's hospital was associated with decreased total inpatient costs and decreased treatment with closed reduction with internal fixation in favor of open reduction with internal fixation. Future studies should seek to identify the specific surgical procedures performed and match patients more closely based specific fracture pattern. LEVEL OF EVIDENCE: Prognostic level II.

Does the Modified Gartland Classification Clarify Decision Making?

HYPOTHESIS: The modified Gartland classification system for pediatric supracondylar fractures is often utilized as a communication tool to aid in determining whether or not a fracture warrants operative intervention. This study sought to determine the interobserver and intraobserver reliability of the Gartland classification system, as well as to determine whether there was agreement that a fracture warranted operative intervention regardless of the classification system. METHODS: A total of 200 anteroposterior and lateral radiographs of pediatric supracondylar humerus fractures were retrospectively reviewed by 3 fellowship-trained pediatric orthopaedic surgeons and 2 orthopaedic residents and then classified as type I, IIa, IIb, or III. The surgeons then recorded whether they would treat the fracture nonoperatively or operatively. The κ coefficients were calculated to determine interobserver and intraobserver reliability. RESULTS: Overall, the Wilkins-modified Gartland classification has low-moderate interobserver reliability (κ=0.475) and high intraobserver reliability (κ=0.777). A low interobserver reliability was found when differentiating between type IIa and IIb (κ=0.240) among attendings. There was moderate-high interobserver reliability for the decision to operate (κ=0.691) and high intraobserver reliability (κ=0.760). Decreased interobserver reliability was present for decision to operate among residents. For fractures classified as type I, the decision to operate was made 3% of the time and 27% for type IIa. The decision was made to operate 99% of the time for type IIb and 100% for type III. SUMMARY: There is almost full agreement for the nonoperative treatment of Type I fractures and operative treatment for type III fractures. There is agreement that type IIb fractures should be treated operatively and that the majority of type IIa fractures should be treated nonoperatively. However, the interobserver reliability for differentiating between type IIa and IIb fractures is low. Our results validate the Gartland classfication system as a method to help direct treatment of pediatric supracondylar humerus fractures, although the modification of the system, IIa versus IIb, seems to have limited reliability and utility. Terminology based on decision to treat may lead to a more clinically useful classification system in the evaluation and treatment of pediatric supracondylar humerus fractures. LEVEL OF EVIDENCE: Level III-diagnostic studies.