Diagnosis Of Scaphoid Fractures Research Articles

Interobserver Variability Among Radiologists for Diagnosis of Scaphoid Fractures by Computed Tomography

To determine the interobserver variability among radiologists for computed tomography (CT) diagnosis of scaphoid fractures. Four specialized musculoskeletal radiologists evaluated the CT scans of 150 consecutive patients who were clinically suspected of having sustained a scaphoid fracture but whose scaphoid-specific radiographs were normal. The radiologists were asked to determine the presence or absence of a scaphoid fracture and to localize the fracture. Interobserver agreement was calculated using the kappa statistic. The radiologists diagnosed between 11 (7%) and 22 (15%) scaphoid fractures; the kappa value was 0.51. Agreement on the presence of a scaphoid fracture and its location on a CT scan was moderate among the 4 radiologists. This finding raises the question as to whether scaphoid fractures could be under- or overdiagnosed in daily practice when CT is used to exclude or confirm a fracture. This should be kept in mind when interpreting clinical and radiological results in patients with suspected scaphoid fractures.

Acute scaphoid fractures

The most commonly fractured carpal bone is the scaphoid. Scaphoid fractures remain most common in males, but the frequency of scaphoid injury in females is increasing. Suspected scaphoid injuries are ubiquitous and early diagnostic imaging may aid in the diagnosis of scaphoid fractures and prevent needless immobilization. Nonoperative treatment involves some form of immobilization; however, the benefit of inclusion of the elbow, thumb, or both into the cast has not been proven. Nondisplaced fractures of the scaphoid have recently been treated more often with early screw fixation. While this may lead to better functional outcomes, the data establishing this are quite limited, and it may come at the cost of a significantly higher complication rate. Fractures in children over 10 years of age more closely resemble adult patterns. This is thought to be due to increasing body mass index in children and greater participation in high-energy sports.

SCAPHOID NON-UNIONS, WHERE DO THEY COME FROM? THE EPIDEMIOLOGY AND INITIAL PRESENTATION OF 270 SCAPHOID NON-UNIONS

Scaphoid injury and subsequent non-union is a well documented and researched subject. This article gives an overview of the epidemiology and results of the patients we have treated for scaphoid non-union at a University Hospital. 283 scaphoid non-unions in 268 patients (83% men) were operated upon, 230 as a primary and 47 as a secondary. The median age at time of surgery was 27 years. One-third of the non-unions were located in the proximal part of the scaphoid and the remaining two-thirds in the middle part. Of the 146 patients (55%) who contacted a doctor at the time of injury, 53 fractures where diagnosed (20%). Fourteen (5%) were operated primarily while 39 (15%) (seven dislocated) were immobilized in plaster casts. Thirty-two (12%) were under the age of 16 at the time of injury. The average time from the injury to the initial non-union surgery was 1.5 years with 2.8 years to the second procedure. The risk of osteoarthritis increased time from injury to surgery (both primary and secondary procedures). The greatest potential for the reduction of scaphoid non-union is an increased awareness amongst younger men. There is also potential for improved accuracy in the diagnosis of scaphoid fractures (better clinical tests, the use of radiographs, CTs and MRIs) in order to identify the fracture and evaluate dislocation at the initial injury. Early diagnosis and treatment of fractures and non-unions will reduce the development of degenerative wrist changes.

Skaphoidfrakturen im Kindesalter

This article reviews current knowledge about scaphoid fractures in children and adolescents, including the development of the scaphoid, its injuries and age-specific treatment for acute and late presenting fractures. The following recommendations are based on the literature, although scientific evidence to support treatment strategies is scarce. The diagnosis of scaphoid fractures is often missed on initial X-rays. Therefore all suspected fractures should be treated with a thumb spica cast for 2weeks, followed by clinical examination and repeat X-ray if symptoms persist. In cases of negative X-ray findings an MRI or alternatively a CT scan are indicated. None or minimally displaced paediatric scaphoid fractures should be treated in a spica cast for at least 7 weeks until union is documented. Unlike in adults, evidence has not been provided for a benefit of routine surgical therapy. Late presenting non-unions that have not yet been treated adequately warrant a trial of conservative therapy, because healing can be expected under prolonged immobilisation. Surgical treatment should be reserved for dislocated fractures, established pseudarthroses that have not united under adequate conservative treatment or for patients to whom prolonged immobilisation does not appear to be acceptable.

Commentary on an article by Wouter Mallee, MSc, et al.: “Comparison of CT and MRI for Diagnosis of Suspected Scaphoid Fractures”

Despite extensive study, the optimal imaging modality for the diagnosis of a suspected scaphoid fracture remains controversial. Traditionally, patients with clinical findings consistent with scaphoid fracture but with negative initial radiographs have been managed with splint or cast immobilization followed by repeat clinical and radiographic examination two weeks following injury. However, given the relatively low prevalence of true fractures in this population, the classical approach has been criticized for overtreating a majority of these patients. To avoid diagnostic delay and unnecessary immobilization, advanced imaging techniques have gained popularity to facilitate early definitive diagnosis of scaphoid fractures. Studies advocating the use of magnetic resonance imaging (MRI), computed tomography (CT), bone scintigraphy, and ultrasound in the evaluation of suspected scaphoid fractures are plentiful. Among these imaging modalities, MRI has emerged as a relative gold standard, due to both its excellent reported diagnostic performance as well as its ability to identify alternate causes of wrist pain. Criticisms of MRI have been that it is susceptible to misinterpretation of injuries such as bone bruises, potentially resulting in false positive results, and that it has limited capacity to demonstrate subtle degrees of fracture displacement. The use of CT in the acute diagnosis of scaphoid fractures is less well documented but has been advocated because of its lower costs and widespread availability, although the diagnostic accuracy of CT in this situation has been questioned1. Although current institutional protocols vary, an often recommended algorithm is to first proceed …

Does the two-week delayed scaphoid X-ray series truly aid the diagnosis of scaphoid fractures?

Does the two-week delayed scaphoid X-ray series truly aid the diagnosis of scaphoid fractures?

Review of imaging of scaphoid fractures

Scaphoid fractures are the most common fractures of the carpus, accounting for 79% of all carpal fractures. Early diagnosis of scaphoid fractures is imperative owing to potential complications following the fracture, including non-union, avascular necrosis, carpal instability and osteoarthritis. Plain radiography remains the initial imaging modality to assess scaphoid fractures. Magnetic resonance imaging (MRI) is excellent in the detection of clinically suspected, but initially radiographically negative, scaphoid fractures. Cost-effectiveness analysis studies have demonstrated MRI is effective in this setting. Gadolinium enhanced MRI has been shown to be superior to unenhanced MRI in the detection of avascular necrosis. Computerized tomography scan is the preferred modality to assess the intricacies of scaphoid fracture, including fracture location and deformity, as well as union status. This review paper explores the recent advances in imaging of the scaphoid, with reference also to avascular necrosis and non-union following a scaphoid fracture.

Clinical Examination of Scaphoid Fractures

Undetected scaphoid fractures may lead to complications, including nonunion, malunion, avascular necrosis, and wrist arthritis. A competent physical examination is essential for the diagnosis of scaphoid fractures in the setting of occult fractures presenting with normal radiographs. The differential diagnosis of occult scaphoid fractures includes acute tears of the scaphoid-lunate ligament, Kienbock's disease, occult ganglion, nondisplaced radial styloid fractures, and injury to the radial aspect of the radio-scapho-capitate ligament. All of these may have normal plain radiographs but often can be distinguished based on physical examination findings. The 2 key points of such an examination include the exact location of point tenderness and provocative special tests. Although Watson's scaphoid shift test is classically described for scaphoid instability, we highlight its significance in the setting of scaphoid fractures.

Scaphoid Fracture Detection in a Military Population: A Standardized Approach for Medical Referral

The objective was to test, refine, and implement an algorithm for early detection and referral of clinical scaphoid fractures by U.S. Army medical personnel. Our goal was to reduce complications resulting from delayed diagnosis and to improve outcomes affecting soldier health and unit readiness. Data on scaphoid fractures treated in the orthopedic department at Tripler Army Medical Center were collected from January 1, 2001, through December 31, 2003. Demographic variables included gender, age, and military rank. The incidence of scaphoid fractures in our population was 43 cases per 100,000 personnel per year. An algorithm to guide nonorthopedic providers was developed after review of the medical literature. We present an algorithm-based approach to soldiers presenting with post-traumatic wrist pain. The algorithm was fashioned with the aim of reducing complications and poor outcomes associated with delayed diagnosis of scaphoid fractures, affecting soldier health and unit readiness. A prospective study of the algorithm is underway.

Comparison of Sagittal Computed Tomography and Plain Film Radiography in a Scaphoid Fracture Model

To compare computed tomography (CT) in the sagittal plane and plain film radiography in the diagnosis of scaphoid fracture and displacement. Three groups of scaphoids (no fracture, undisplaced fractures, fractures with displacement > 1 mm) from 11 cadaver wrists were prepared. Each wrist then was imaged by using sagittal plane CT scans in the long axis of the scaphoid and plain film imaging using 6 standard scaphoid views. Eight readers from 3 specialties read each group of images. The sensitivity and specificity for the presence of fracture and fracture displacement were calculated in addition to interobserver and intraobserver reliabilities for each. Both x-ray and CT scans showed a high sensitivity and specificity in detecting the presence of a fracture with no interspecialty differences. The sensitivity for displacement greater than 1 mm was lower for both modalities with no inter-specialty differences. The specificities for x-ray and CT for detecting displacement greater than 1 mm were 84% and 89%, respectively. The poor sensitivity for detecting displacement was explained by the low sensitivity of CT in the diagnosis of radial/ulnar displacement compared with x-ray and the low sensitivity of x-ray in the diagnosis of volar/dorsal displacement compared with CT scans. When fellowship-trained hand surgeons reviewed CT scans and plain films together the sensitivity and specificity for fracture displacement increased significantly. Intraobserver and interobserver reliability for both x-ray and CT scans was excellent except for the reading of CT scans among emergency physicians and for the reading of plain x-rays among senior house staff, representing moderate agreement. Based on these results both CT scans in the sagittal plane and plain films accurately detect fractures with a high degree of interobserver and intraobserver reliability, but they fall short in detecting displacement greater than 1 mm.

MANAGEMENT OF ACUTE SCAPHOID FRACTURES

Scaphoid fractures in the athlete present a dilemma to the treating clinician. Diagnosis of scaphoid fractures should be suspected in any athlete, especially those participating in contact sports, presenting with radial wrist pain. Appropriate imaging studies should be obtained to make a timely and complete diagnosis. Treatment alternatives for acute scaphoid fractures in the athlete include casting and staying out of sports, casting with use of a playing cast, and internal fixation. Displaced unstable fractures and proximal pole fractures should be treated by open reduction and internal fixation. Nondisplaced mid-third fractures are the most common type seen in the athlete. Alternatives of treatment should be carefully explained to the patients and family and the most appropriate treatment employed.

Diagnosis of scaphoid fracture and dedicated extremity MRI.

We evaluated the value of dedicated extremity magnetic resonance imaging (E-MRI) in patients with clinical suspicion of a scaphoid fracture and normal initial radiographs. 52 patients underwent E-MRI within a mean of 4 (2-10) days after trauma. Follow-up radiographs were performed at average 11 (8-14) weeks after trauma, and these images were used as the "gold standard". A T1-weighted turbo gradient echo 3D and a tau short inversion recovery STIR were performed, both in coronal planes. The imaging time was less than 10 min. The images were evaluated independently by two radiologists. E-MRI detected occult fractures of the scaphoid in 9 patients, and of the distal radius in a further 6 patients. All these fractures were confirmed at follow-up radiographs. Furthermore, E-MRI revealed a fracture of the capitate bone in 1 patient, and of the triquetrum in 2 patients, and in 8 patients, bone bruise in 1 or more of the carpal bones. However, these fractures and bone lesions could not be confirmed by the follow-up radiographs. The agreement between the two examiners was high (kappa = 0.8) for E-MRI detection of fractures. E-MRI seems to be better than radiographs in the early diagnosis of occult fractures of the scaphoid bone and the wrist.

Combining the clinical signs improves diagnosis of scaphoid fractures: A prospective study with follow-up

This is a prospective study evaluating the efficacy of four clinical signs believed to be useful in the diagnosis of scaphoid fracture. Two hundred and fifteen consecutive patients with suspected scaphoid fracture were examined on two separate occasions to evaluate tenderness in the anatomical snuff box (ASB), tenderness over the scaphoid tubercle (ST), pain on longitudinal compression of the thumb (LC) and the range of thumb movement (TM). At the initial examination ASB, ST and LC were all 100% sensitive for detecting scaphoid fracture with specificities of 9%, 30% and 48% respectively. These clinical signs used in combination, within the first 24 hours following injury, produced 100% sensitivity and an improvement in the specificity to 74%. TM had 69% sensitivity and 66% specificity. Our results suggest that these clinical signs are inadequate indicators of scaphoid fracture when used alone and should be combined to achieve a more accurate clinical diagnosis.

Is intrasound vibration useful in the diagnosis of occult scaphoid fractures?

This study was designed to confirm the results of Finkenberg et al. (J Hand Surg 1993;18A: 4-7), who found a high sensitivity (100%) and specificity (95%) of the intrasound vibration method in diagnosing occult scaphoid fractures. These occult scaphoid fractures are not visible on x-ray films, but clinically the patients are suspected of having a scaphoid fracture. A vibratory apparatus is placed over the anatomical snuff-box and a vibration of 100 mW is emitted; a painful sensation is produced if the scaphoid is fractured. Thirty-seven consecutive patients with a clinically suspected scaphoid fracture were evaluated. In 6 patients, a scaphoid fracture was radiographically identified; in the remaining 31 patients, a 3-phase bone scan was obtained. Eleven wrists showed increased uptake over the scaphoid and were considered to have an occult scaphoid fracture. In this group, bone scintigraphy was used as the reference standard. The vibration test was painful in 1 of 6 patients with a proven scaphoid fracture and in 3 of the 11 patients with a positive bone scan. In contrast to the results of Finkenberg et al, the intrasound vibration method shows a sensitivity of 24%, a specificity of 85%, a positive predictive value of 40%, and a negative predictive value of 65%. We conclude that the accuracy of intrasound vibration is low and that it is not useful in the diagnosis of scaphoid fractures.

Intrasound vibration in the early diagnosis of scaphoid fracture

A prospective trial was designed to assess the sensitivity and specificity of intrasound vibration for the early detection of scaphoid fracture. We replicated the method described by Finkenburg et al. (J Hand Surg 1993;18A:4-7) in an attempt to corroborate their results. We found the test to be 73% sensitive and 51% specific. Because the test was not 100% sensitive, as claimed by Finkenburg et al., we discontinued the use of this device in our hospital.

The value of additional carpal box radiographs in suspected scaphoid fracture.

Carpal Box (CB) radiographs, transverse and longitudinal, produce elongated and magnified views of the carpus. These radiographs can be used after carpal injury, in addition to conventional scaphoid x-rays. In this study, the use of CB radiographs was evaluated in patients with possible scaphoid fracture. Seventy-one consecutive patients who presented at the First Aid department from May 1994 to May 1995 were included. All patients were examined for scaphoid fracture after a fall on the out-stretched hand. If a scaphoid fracture was seen on the scaphoid x-rays, patients were immobilized. If the x-rays remained negative or dubious for fracture, additional transverse and longitudinal CB radiographs were obtained. If CB radiographs remained negative or inconclusive, patients were referred for three-phase bone scintigraphy. The results of independent and masked judgment by three different observers were used for an inter- and intraobserver analysis. Twenty of 71 patients initially showed a scaphoid fracture on the conventional scaphoid x-rays, 41 were negative, and 10 inconclusive. All 41 negative patients remained negative on CB radiograph; however, the bone scintigraphy was positive for scaphoid fracture in 11 patients and in 9 patients a hot spot elsewhere in the carpus was found. Of the 10 patients with inconclusive x-rays, 2 showed a clear fracture of the scaphoid on CB radiograph, 5 were negative, and 3 remained inconclusive. The agreement between observers, calculated in kappa values, was highest in CB radiographs. In the diagnosis of scaphoid fracture, Carpal Box radiography is of limited value in patients with clinically suspected scaphoid fracture. In two of 10 patients with initial dubious scaphoid x-ray, bone scintigraphy can be avoided. Furthermore, the reliability of the interpretation of the radiographs is increased by additional Carpal Box radiography.

Can a Day 4 Bone Scan Accurately Determine the Presence or Absence of Scaphoid Fracture?

To evaluate the accuracy of day 4 bone scans in predicting the presence or absence of fracture in patients with "clinical scaphoid fracture." Prospective sensitivity study of ED patients with clinical scaphoid fractures. Each patient was immobilized in a thumb spica cast and had day 4 bone scans of both wrists and hands. Blinded day 4 bone scan results were ultimately compared with the diagnosis on day 14 when patients returned for repeat clinical examination and radiographs. In cases of equivocal radiographic or clinical examination results, a day 14 bone scan was performed. Two tertiary care teaching hospital emergency departments. All ED patients older than 16 years with the diagnosis of clinical scaphoid fracture were eligible. Ninety-nine patients were enrolled and successfully completed the study protocol from October 1990 through November 1992. One patient had bilateral injury, for a total of 100 completed studies. Day 4 bone scans were 100% sensitive and 92% specific, for a positive predictive value of 65%, a negative predictive value of 100%, and accuracy of 93% (95% confidence interval, 88%, to 98%). Many other types of fractures were identified on the day 4 scans, including those of the triquetra, distal radius, capitate, hamate, trapezoid, trapezium, and metacarpals. Day 4 bone scans are an accurate means of ruling out scaphoid fracture. However, because of a significant number of false-positive scans at day 4, they do not reliably confirm the diagnosis of scaphoid fracture. The bone scans also permitted identification of several other wrist fractures that had not been radiographically apparent.

The reliability of the 3-phase bone scan in suspected scaphoid fracture: an inter- and intraobserver variability analysis.

In the diagnosis of scaphoid fracture, the dynamic phase of the radionuclide bone scan alone has been recommended as an early test. To evaluate the independent reliability of the dynamic and static phases of the 3-phase bone scan in this diagnosis, 3 examiners reviewed the 3-phase bone scans of a series of 60 patients with clinical signs of fracture of the carpal scaphoid and with negative or non-diagnostic initial radiographs. The interpretation was performed independently and without the benefit of additional data. The bone scans were reviewed after 1 year by the same observers. The results were analyzed using kappa statistics. The bone scan was suspicious of fracture of the scaphoid in 15 patients. Irrespective of training and experience, the kappa values of the dynamic bone scan between any 2 observers did not exceed 0.57. The kappa values increased significantly when the static phase of the bone scan was examined (> 0.81). The intraobserver variability showed a similar pattern. We conclude that in suspected scaphoid fracture, the dynamic phase of the radionuclide bone scan alone cannot be used as a reliable diagnostic approach because of the low inter- and intraobserver agreement in the interpretation, irrespective of the experience and training of the observer.

Magnetic resonance imaging in scaphoid fractures

The use of a 1.5 tesla superconducting M.R. imager and surface coil was found to enhance the ability of M.R.I. to depict the fine anatomy of the wrist. Five healthy volunteers and 28 patients with scaphoid fractures underwent M.R.I., which made possible a definitive diagnosis of scaphoid fractures at an early stage. A fresh fracture was identified by decreased or iso signal intensity on the T1-weighted image and increased signal intensity on the T2-weighted image. This increase continued until bony union was apparent on radiographs. On the T2-weighted image, high signal intensity was characteristic of fresh fractures and suggested that bony union was possible. When bony union was complete, the intensity of the signal for the scaphoid on both T1- and T2-weighted images returned to normal. M.R.I. should thus prove useful in the diagnosis of scaphoid fractures.

Diagnosing scaphoid fractures: radiographs cannot be used as a gold standard!

To evaluate the reproducibility of the interpretation of radiographs for the diagnosis of scaphoid fractures, 134 radiographs (60 consecutive patients) were blindly observed by a resident radiologist, consultant radiologist, resident trauma surgeon and consultant trauma surgeon. The results of radiographs were analysed using kappa (kappa) statistics and stratified according to the results of the corresponding bone scan. In 23 patients the bone scan was positive for fracture of the scaphoid. Irrespective of training and experience, the kappa of the comparison of the scores of the radiographs between any two observers did not exceed 40 per cent. After stratification of the outcome of the bone scan, the kappa did not increase significantly. A panel of three experienced observers gave their opinion of all radiographs. The results were compared with the bone scan results. We conclude that radiographs in suspected scaphoid fracture cannot be used as a reliable diagnostic approach because of the low inter-observer agreement in the interpretation, irrespective of the experience and training of the observer.