Clinical and cost implications of using immediate MRI in the management of patients with a suspected scaphoid fracture and negative radiographs results from the SMaRT trial

The rate of nonunion in the MRI-detected occult scaphoid fracture

Aims

There is a lack of published evidence relating to the rate of nonunion seen in occult scaphoid fractures, diagnosed only after MRI. This study reports the rate of delayed union and nonunion in a cohort of patients with MRI-detected acute scaphoid fractures.

Methods

This multicentre cohort study at eight centres in the UK included all patients with an acute scaphoid fracture diagnosed on MRI having presented acutely following wrist trauma with normal radiographs. Data were gathered retrospectively for a minimum of 12 months at each centre. The primary outcome measures were the rate of acute surgery, delayed union, and nonunion.

Results

A total of 1,989 patients underwent acute MRI for a suspected scaphoid fracture during the study period, of which 256 patients (12.9%) were diagnosed with a previously occult scaphoid fracture. Of the patients with scaphoid fractures, six underwent early surgical fixation (2.3%) and there was a total of 16 cases of delayed or nonunion (6.3%) in the remaining 250 patients treated with cast immobilization. Of the nine nonunions (3.5%), seven underwent surgery (2.7%), one opted for non-surgical treatment, and one failed to attend follow-up. Of the seven delayed unions (2.7%), one (0.4%) was treated with surgery at two months, one (0.4%) did not attend further follow-up, and the remaining five fractures (1.9%) healed after further cast immobilization. All fractures treated with surgery had united at follow-up. There was one complication of surgery (prominent screw requiring removal).

Conclusion

MRI-detected scaphoid fractures are not universally benign, with delayed or nonunion of scaphoid fractures diagnosed only after MRI seen in over 6% despite appropriate initial immobilization, with most of these patients with nonunion requiring surgery to achieve union. This study adds weight to the evidence base supporting the use of early MRI for these patients.

Patient-directed follow-up for the clinical scaphoid fracture

Aims

Occult (clinical) injuries represent 15% of all scaphoid fractures, posing significant challenges to the clinician. MRI has been suggested as the gold standard for diagnosis, but remains expensive, time-consuming, and is in high demand. Conventional management with immobilization and serial radiography typically results in multiple follow-up attendances to clinic, radiation exposure, and delays return to work. Suboptimal management can result in significant disability and, frequently, litigation.

Methods

We present a service evaluation report following the introduction of a quality-improvement themed, streamlined, clinical scaphoid pathway. Patients are offered a removable wrist splint with verbal and written instructions to remove it two weeks following injury, for self-assessment. The persistence of pain is the patient's guide to 'opt-in' and to self-refer for a follow-up appointment with a senior emergency physician. On confirmation of ongoing signs of clinical scaphoid injury, an urgent outpatient 'fast'-wrist protocol MRI scan is ordered, with instructions to maintain wrist immobilization. Patients with positive scan results are referred for specialist orthopaedic assessment via a virtual fracture clinic.

Results

From February 2018 to January 2019, there were 442 patients diagnosed as clinical scaphoid fractures. 122 patients (28%) self-referred back to the emergency department at two weeks. Following clinical review, 53 patients were discharged; MRI was booked for 69 patients (16%). Overall, six patients (< 2% of total; 10% of those scanned) had positive scans for a scaphoid fracture. There were no known missed fractures, long-term non-unions or malunions resulting from this pathway. Costs were saved by avoiding face-to-face clinical review and MRI scanning.

Conclusion

A patient-focused opt-in approach is safe and effective to managing the suspected occult (clinical) scaphoid fracture.

Which clinical features best predict occult scaphoid fractures? A systematic review of diagnostic test accuracy studies

BACKGROUND

Plain radiographs cannot identify all scaphoid fractures; thus ED patients with a clinical suspicion of scaphoid injury often undergo immobilisation despite normal imaging. This study determined (1) the prevalence of scaphoid fracture among patients with a clinical suspicion of scaphoid injury with normal radiographs and (2) whether clinical features can identify patients that do not require immobilisation and further imaging.

METHODS

This systematic review of diagnostic test accuracy studies included all study designs that evaluated predictors of scaphoid fracture among patients with normal initial radiographs. Quality assessment was undertaken using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Meta-analyses included all studies.

RESULTS

Eight studies reported data on 1685 wrist injuries. The prevalence of scaphoid fracture despite normal radiographs was 9.0%. Most studies were at overall low risk of bias but two were at unclear risk; all eight were at low risk for applicability concerns. The most accurate clinical predictors of occult scaphoid fracture were pain when the examiner moved the wrist from a pronated to a supinated position against resistance (sensitivity 100%, specificity 97.9%, LR+ 45.0, 95% CI 6.5 to 312.5), supination strength <10% of contralateral side (sensitivity 84.6%, specificity 76.9%, LR+ 3.7, 95% CI 2.2 to 6.1), pain on ulnar deviation (sensitivity 55.2%, specificity 76.4%, LR+ 2.3, 95% CI 1.8 to 3.0) and pronation strength <10% of contralateral side (sensitivity 69.2%, specificity 64.6%, LR+ 2.0, 95% CI 1.2 to 3.2). Absence of anatomical snuffbox tenderness significantly reduced the likelihood of an occult scaphoid fracture (sensitivity 92.1%, specificity 48.4%, LR- 0.2, 95% CI 0.0 to 0.7).

CONCLUSION

No single feature satisfactorily excludes an occult scaphoid fracture. Further work should explore whether a combination of clinical features, possibly in conjunction with injury characteristics (such as mechanism) and a normal initial radiograph might exclude fracture. Pain on supination against resistance would benefit from external validation.

TRIAL REGISTRATION NUMBER

CRD42021290224.

Scaphoid and Carpal Bone Fracture: The Difficult Cases and Approach to Management

Scaphoid and carpal bone fractures are challenging injuries to manage and have significant functional implications. Prompt diagnosis is important and relies on systematic evaluation via history, examination, and imaging. Cross-sectional imaging is often helpful for diagnosis and treatment planning. Treatment for nondisplaced fractures is often closed but these injuries typically require prolonged immobilization and may still result in nonunion or avascular necrosis. Displaced carpal bone fractures, and those associated with carpal instability, typically require open reduction internal fixation.

Thousand shades of gray - The role of imaging display in diagnosis of occult scaphoid fractures - A pilot study

Introduction

Most hospitals and clinics utilize commercial grade displays for viewing wrist radiographs. There is no evidence regarding the role of the imaging display used to evaluate the radiographs. The aim of this study was to compare the rates of scaphoid fracture diagnosis by commercial grade and medical grade displays.

Methods

Wrist radiographs of patients that had clinical signs of scaphoid fracture without findings on plain radiography (suspected scaphoid fractures) were retrospectively collected from ER department and interpreted for radiographic signs of fracture by four orthopedics seniors commercial grade and medical grade displays. The difference in fracture diagnosis rates were studied. Inter- and intra-observer variability were also studied.

Results

Study population comprised of 175 high quality wrist radiographs were interpreted. Mean 48.25 (27%) scaphoid fractures were observed on commercial grade display compared to 66 (38.2%) on medical grade display (p = 0.076). The total inter-observer agreement could be defined as a moderate agreement (κ = 0.527, Accuracy = 0.77). Total agreement between all observers were observed in 86 (49.1%) cases compared to 89 (50.9%) cases when reviewing X-rays on commercial and medical displays, respectively.

Discussion

The scaphoid fracture detection rate on medical grade display was not statistically higher compared to non-medical grade displays, but we did find a tendency toward medical grade display. We found that in a substantial number of cases, our observers recognize signs of fracture that were initially evaluated as "suspected fracture" by the ER physicians. As a pilot study, we found evidence that support the need for a prospective study designed to compare the observations to a gold standard modality, such as MRI. We believe utilizing medical grade displays can increase the rate of diagnosis in cases of clinically suspected scaphoid fractures and better manage the clinical scenario of a suspected scaphoid fracture.

The reliability and clinical utility of a simple MRI based classification tool for acute scaphoid injuries: the OxSMART

Aims

The evidence demonstrating the superiority of early MRI has led to increased use of MRI in clinical pathways for acute wrist trauma. The aim of this study was to describe the radiological characteristics and the inter-observer reliability of a new MRI based classification system for scaphoid injuries in a consecutive series of patients.

Methods

We identified 80 consecutive patients with acute scaphoid injuries at one centre who had presented within four weeks of injury. The radiographs and MRI scans were assessed by four observers, two radiologists, and two hand surgeons, using both pre-existing classifications and a new MRI based classification tool, the Oxford Scaphoid MRI Assessment Rating Tool (OxSMART). The OxSMART was used to categorize scaphoid injuries into three grades: contusion (grade 1); unicortical fracture (grade 2); and complete bicortical fracture (grade 3).

Results

In total there were 13 grade 1 injuries, 11 grade 2 injuries, and 56 grade 3 injuries in the 80 consecutive patients. The inter-observer reliability of the OxSMART was substantial (Kappa = 0.711). The inter-observer reliability of detecting an obvious fracture was moderate for radiographs (Kappa = 0.436) and MRI (Kappa = 0.543). Only 52% (29 of 56) of the grade 3 injuries were detected on plain radiographs. There were two complications of delayed union, both of which occurred in patients with grade 3 injuries, who were promptly treated with cast immobilization. There were no complications in the patients with grade 1 and 2 injuries and the majority of these patients were treated with early mobilization as pain allowed.

Conclusion

This MRI based classification tool, the OxSMART, is reliable and clinically useful in managing patients with acute scaphoid injuries. Cite this article: Bone Jt Open 2022;3(11):913–920.

A Virtual Fracture Clinic Pathway for Managing Suspected Paediatric Scaphoid Fractures

Introduction: The mismanagement of an occult scaphoid fracture is a significant concern in patients presenting with anatomical snuffbox tenderness and no radiographic signs of injury.

Aim: This study investigated whether a virtual fracture clinic (VFC) could improve care efficiency and expedite management decisions surrounding suspected pediatric scaphoid fractures.

Method: Data was reviewed for patients referred via the VFC for suspected scaphoid fractures at a local trauma unit over 19 months. Patients received an "appointment" in VFC. Based on their notes and imaging, patients were referred to an outpatient clinic for repeat radiographs within two weeks (if initial radiographs demonstrated no fracture). Patients with unremarkable second x-rays were contacted and informed to mobilize and return if the pain persisted at four weeks.

Results: The pathway received 175 referrals; 114 male, 61 female, mean age 14 years, range 9-17) with 42 scaphoid fractures diagnosed, 35 (83.3%) on first x-ray, and 7 (16.7%) occult fractures. The pathway managed all patients as intended; 71 patients were seen face-to-face in the clinic due to age or pathology picked up on the first x-ray, and 104 required repeat radiographs. Following the second radiograph, 78 patients were discharged directly. Twenty-six patients required further review in a face-to-face clinic after their second radiograph.

Conclusion: VFC appears to be a safe and efficient method of managing patients with suspected scaphoid fractures on short-term follow-up analysis. This cohort presents no 'missed' injuries and therefore appears safe compared to conventional treatment pathways.

Virtual management of clinically suspected scaphoid fractures

AIMS

The aim of this study was to describe the introduction of a virtual pathway for the management of patients with a suspected fracture of the scaphoid, and to report patient-reported outcome measures (PROMs) and satisfaction following treatment using this service.

METHODS

All adult patients who presented with a clinically suspected scaphoid fracture that was not visible on radiographs at the time of presentation during a one-year period were eligible for inclusion in the pathway. Demographic details, findings on examination, and routine four-view radiographs at the time of presentation were collected. All radiographs were reviewed virtually by a single consultant hand surgeon, with patient-initiated follow-up on request. PROMs were assessed at a minimum of one year after presentation and included the abbreviated version of the Disabilities of the Arm, Shoulder and Hand Score (QuickDASH), the EuroQol five-dimension five-level health questionnaire (EQ-5D-5L), the Net Promoter Score (NPS), and return to work.

RESULTS

A total of 221 patients were referred to the virtual pathway. Their mean age was 41 years (range 16 to 87) and there were 99 male patients (45%). A total of 189 patients (86%) were discharged with advice and 19 (9%) were recalled for clinical review: seven with an undisplaced scaphoid fracture, six with another fracture of the hand or wrist, two with a scapholunate ligament injury, and four in whom no abnormality was detected. A total of 13 patients (6%) initiated follow-up with the hand service: no fracture or ligament injury was identified in this group. PROMs were available for 179 patients (81%) at a mean follow-up of 19 months (range 13 to 33). The median QuickDASH score was 2.3 (interquartile range (IQR) 0 to 15.9), the median EQ-5D-5L was 0.85 (IQR 0.73 to 1.00), the NPS was 76, and 173 patients (97%) were satisfied with their treatment. There were no documented cases of symptomatic nonunion one year following injury.

CONCLUSION

We describe the introduction of a virtual pathway for the management of patients with a suspected scaphoid fracture. We found high levels of patient satisfaction, excellent PROMs, and no detrimental effects in the vast majority of cases. Cite this article: Bone Joint J 2022;104-B(6):709-714.

Diagnosis of Suspected Scaphoid Fractures

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Suspected scaphoid fractures are a diagnostic and therapeutic challenge despite the advances in knowledge regarding these injuries and imaging techniques. The risks and restrictions of routine immobilization as well as the restriction of activities in a young and active population must be weighed against the risks of nonunion that are associated with a missed fracture.

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The prevalence of true fractures among suspected fractures is low. This greatly reduces the statistical probability that a positive diagnostic test will correspond with a true fracture, reducing the positive predictive value of an investigation.

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There is no consensus reference standard for a true fracture; therefore, alternative statistical methods for calculating sensitivity, specificity, and positive and negative predictive values are required.

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Clinical prediction rules that incorporate a set of demographic and clinical factors may allow stratification of secondary imaging, which, in turn, could increase the pretest probability of a scaphoid fracture and improve the diagnostic performance of the sophisticated radiographic investigations that are available.

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Machine-learning-derived probability calculators may augment risk stratification and can improve through retraining, although these theoretical benefits need further prospective evaluation.

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Convolutional neural networks (CNNs) are a form of artificial intelligence that have demonstrated great promise in the recognition of scaphoid fractures on radiographs. However, in the more challenging diagnostic scenario of a suspected or so-called "clinical" scaphoid fracture, CNNs have not yet proven superior to a diagnosis that has been made by an experienced surgeon.

The management of suspected scaphoid fractures in the UK: a national cross-sectional study

AIMS

Current National Institute for Health and Clinical Excellence (NICE) guidance advises that MRI direct from the emergency department (ED) should be considered for suspected scaphoid fractures. This study reports the current management of suspected scaphoid fractures in the UK and assesses adherence with NICE guidance.

METHODS

This national cross-sectional study was carried out at 87 NHS centres in the UK involving 122 EDs and 184 minor injuries units (MIUs). The primary outcome was availability of MRI imaging direct from the ED. We also report the specifics of patient management pathways for suspected scaphoid fractures in EDs, MIUs, and orthopaedic services. Overall, 62 of 87 centres (71%) had a guideline for the management of suspected scaphoid fractures.

RESULTS

A total of 11 of 87 centres (13%) had MRI directly available from the ED. Overall, 14 centres (17%) used cross-sectional imaging direct from the ED: MRI in 11 (13%), CT in three (3%), and a mixture of MRI/CT in one (1%). Four centres (6%) used cross-sectional imaging direct from the MIU: MRI in three (4%) and CT in two (2%). Of 87 centres' orthopaedic specialist services, 74 (85%) obtained repeat radiographs, while the most common form of definitive imaging used was MRI in 55 (63%), CT in 16 (19%), mixture of MRI/CT in three (3%), and radiographs in 11 (13%).

CONCLUSION

Only a small minority of centres currently offer MRI directly from the ED for patients with a suspected scaphoid fracture. Further research is needed to investigate the facilitators and barriers to the implementation of NICE guidance. Cite this article: Bone Jt Open 2021;2(11):997-1003.

Evaluating the potential for cone beam CT to improve the suspected scaphoid fracture pathway: InSPECTED - A single-centre feasibility study

BACKGROUND

The suspected scaphoid fracture remains a diagnostic conundrum with over-treatment a common risk-averse strategy. Cross-sectional imaging remains the gold standard with MRI recommended but CT used by some because of easier access or limited MRI availability. The aim of this feasibility study was to evaluate whether cone beam computed tomography (CBCT) could support early diagnosis, or exclusion, of scaphoid fractures.

METHODS

Patients with a suspected scaphoid were recruited fracture between March and July 2020. All underwent a 4-view X-ray. If this examination was normal, they were immediately referred for a CBCT scan of the wrist. Those with a normal scan were discharged to research follow-up at 2 and 6-weeks.

RESULTS

68 participants were recruited, 55 had a normal or equivocal X-ray and underwent CBCT. Nine additional radiocarpal fractures (16.2%) were demonstrated on CBCT, the remainder were discharged to research follow-up. Based on the 2-week and 6-week follow up three patients (4.4%) were referred for MRI to investigate persistent symptoms with no bony injuries identified.

CONCLUSIONS

CBCT scans enabled a rapid pathway for the diagnosis or exclusion of scaphoid fractures, identifying other fractures and facilitating early treatment. The rapid pathway also enabled those with no bony injury to start rehabilitation, suggesting that patients can be safely discharged with safety-net advice following a CBCT scan.

How to manage scaphoid waist fractures? Introduction of pragmatic imaging efficient pathway and literature review of the recent evidence

INTRODUCTION AND OBJECTIVE

The scaphoid bone sustains about 90 % of carpal bone fractures and is the second-highest bone at risk of post-traumatic osteonecrosis. Delayed diagnosis and treatment could lead to non-union and advanced carpal bones collapse. This study aimed to introduce an imaging efficient and practical scaphoid waist fracture management pathway (SWFMP) and measure its efficacy in clinical practice.

MATERIALS AND METHODS

The SWFMP was introduced in January 2020. Suspected occult fractures were approached by early orthopaedic clinical assessment and subsequent urgent MRI scan without repeating scaphoid X-rays. Scaphoid waist fractures displaced < 2 mm were treated with 8 weeks below elbow cast immobilization followed by CT scan if delayed union was suspected. Waist fractures displaced > 2 mm were managed with surgical fixation. Adult patients referred from the emergency department (ED) to the Virtual Fracture Clinic (VFC) with acute scaphoid injury from January 2019 to October 2019 (Pre SWFMP, n = 29), were identified and compared to those managed from January 2020 to October 2020 (Post SWFMP, n = 33).

RESULTS

Mean age was 37.9 (SD = 20.61) and 36.2 (SD = 17.06) years in the pre-SWFMP and post-SWFMP cohorts respectively. Fiften patients (51.7%) had the right side affected in the pre-SWFMP cohort and twenty-three patients (69.7%) in the post-SWFMP cohort. Scaphoid X-rays requested by ED have increased from 19 (65.5%) to 31 (94%) and repeated X-rays reduced from 17 (58.6%) to 10 (30.3%) after the introduction of the SWFMP. Mean wrist cast immobilization for patients without scaphoid fractures dropped from 16.9 days (SD = 5.57) to 3.6 days (SD = 6.24) after the SWFMP (p = 0.001). In the pre-SWFMP cohort, 24 patients had no fracture, 4 achieved full healing and 1 developed non-union. In the post-SWFMP cohort, 29 patients had no fracture, 1 achieved full union and delayed union was detected in 3 patients at 8 weeks.

CONCLUSIONS

The SWFMP has improved the clinical practice by reducing unnecessary ionizing radiation, unnecessary cast immobilization, and by using a timely fracture fixation intervention.

Suspected scaphoid injuries managed by MRI direct from the emergency department : a single-centre prospective cohort study

Aims

To determine the role of early MRI in the management of suspected scaphoid fractures.

Methods

A total of 337 consecutive patients presenting to an emergency department (ED) following wrist trauma over a 12-month period were prospectively included in this service evaluation project. MRI was not required in 62 patients with clear diagnoses, and 17 patients were not managed as per pathway, leaving a total of 258 patients with normal scaphoid series radiographs who were then referred directly from ED for an acute wrist MRI scan. Patient demographics, clinical details, outcomes, and complications were recorded at a minimum of a year following injury.

Results

The median time from injury to ED presentation was one day and the median number of positive clinical signs was two out of three (snuffbox tenderness, tubercle tenderness, pain on telescoping). Of 258 patients referred for acute MRI, 208 scans were performed as 50 patients either did not tolerate (five patients) or did not attend their scan (45 patients). MRI scans demonstrated scaphoid fracture (13%), fracture of another bone (22%), scaphoid contusion (6%), other contusion/ligamentous injury (20%), or solely degenerative pathology (10%). Only 29% of scans showed no abnormality. Almost 50% of those undergoing MRI (100 patients) were discharged by ED with advice, with only one re-presentation. Of the 27 undisplaced occult scaphoid fractures, despite prompt cast immobilization, two experienced delayed union which was successfully treated with surgery.

Conclusion

The use of MRI direct from ED enables prompt diagnosis and the early discharge of a large proportion of patients with normal radiographs following wrist trauma.

Cite this article: Bone Jt Open 2021;2(6):447–453.

Hot Topics in Hand and Wrist Surgery

The field of hand surgery continues to evolve in new and exciting directions. Advances in diagnosis and management for common complaints and complex injuries allow higher-level care, while still being cognizant of the cost of health care delivery. Indications and protocols for past paradigm shifts, such as volar locked plating for distal radial fractures, continue to be honed, and the outcomes seen for modern flexor tendon repairs are impressive. Open questions remain, but promising results for scaphoid nonunion surgery and peripheral nerve reconstruction with processed allograft will continue to shed light on these unsolved problems.

Service reconfiguration in the department of hand surgery during the UK COVID-19 lockdown: Birmingham experience

In early 2020, the COVID-19 pandemic swept through the UK and had a major impact on healthcare services. The Birmingham hand centre, one of the largest hand trauma units in the country, underwent a dramatic service reconfiguration to enable robust and safe provision of care that would withstand the peak of the pandemic. Streamlining our service significantly reduced patient footfall and hospital admission while preventing intra-hospital viral transmission. Many of the changes implemented have been kept as permanent adjustments to our practice as this new model of care yields higher patient satisfaction and efficacy to withstand the pressures of further peaks in the pandemic.

Cost-Effectiveness of Immediate Magnetic Resonance Imaging In the Management of Patients With Suspected Scaphoid Fracture: Results From a Randomized Clinical Trial

OBJECTIVES

Given the limited diagnostic accuracy of radiographs on presentation to the emergency department (ED), the management of suspected scaphoid fractures remains clinically challenging and poses an unknown economic burden to healthcare systems. We aimed to evaluate the cost-effectiveness of immediate magnetic resonance imaging (MRI) in the management of patients presenting with suspected scaphoid fracture to an ED in England.

METHODS

A pragmatic, randomized, single-center trial compared the use of immediate MRI in the ED against standard care with radiographs only. Participants' use of healthcare services and costs were estimated from primary care and secondary care databases and questionnaires at baseline, 1, 3, and 6 months postrecruitment. Costs were compared using generalized linear models and combined with quality-adjusted life years (QALYs, based on the EQ-5D-5L) to estimate cost-effectiveness at 6 months postrecruitment. Cost-effectiveness acceptability curves and bootstrapping techniques were used to estimate the probability of cost-effectiveness at different willingness-to-pay (WTP) thresholds. Four deterministic sensitivity scenarios were considered around key parameters.

RESULTS

The MRI intervention dominated standard care in the base case and all 4 deterministic sensitivity scenarios, costing less and achieving more QALY gains, with a probability of 100% of being cost-effective at 6 months using the conventional United Kingdom WTP thresholds of £20 000 to £30 000 per QALY.

CONCLUSION

The use of immediate MRI is a cost-effective intervention in the management of suspected scaphoid fractures in a Central Hospital in London. Routine clinical practice at our institution has been changed to include the intervention.