Classifications of Acute Scaphoid Fractures: A Systematic Literature Review

Finite Element Analysis of Postoperative Stability of Transverse Scaphoid Waist Fracture

Background and Purpose

Scaphoid waist fractures are often stabilised with compression screws, Kirschner wires (K-wires), or a combination of both. While clinical and bio-mechanical studies evaluating their utility are available, the ideal configuration of implant that would provide adequate stability to permit early use of the hand is debatable. We examined configurations of a single screw, one screw along with a K-wire, and two K-wires used for a transverse scaphoid waist fracture fixation aiming to assess the stability provided by each in the immediate postoperative period.

Methods

Computer-aided design (CAD) models of the scaphoid, K-wire, and headless compression screw were created. A transverse fracture was created at the scaphoid waist, and the CAD models of the screw and K-wire were used to fix the fracture in different configurations in a distal to proximal direction. Finite Element Analysis (FEA) was used to examine the strength of configurations when they were subjected to compression and distraction forces. The total maximum deformation (TDef) and factor of safety (FoS) for each configuration were calculated and used as indirect indicators of postoperative stability.

Results

When a single screw was used, the configurations with the screw directed posteriorly from either centre or anterior had the best combined TDef and FoS values. For one screw and one K-wire, the configuration with screw and K-wire parallel to each other with the screw located along the long axis in the AP projection and anterior to the K-wire in the lateral projection had the best combined TDef and FoS values. When using two K-wires, configurations with the two wires diverging proximally on the lateral projection had the best combined TDef and FoS values.

Conclusions

When fixing a transverse scaphoid waist fracture with a single screw, the screw directed posteriorly from either the centre or anterior aspect of the distal pole has the best stability, a parallel configuration has the best stability when fixing it using a screw and a K-wire, and divergent configuration has the best stability when fixing it with two K-wires only.

Fracture Gap Closure and Reduction Are Affected by the Orientation of the Headless Compression Screw

BACKGROUND

We evaluated the impact of a variable-pitch headless screw's angle of insertion relative to the fracture plane on fracture gap closure and reduction.

METHODS

Variable-pitch, fully threaded headless screws were inserted into polyurethane blocks of "normal" bone model density using a custom jig. Separate trials were completed with a 28-mm screw placed perpendicular and oblique/longitudinal to varying fracture planes (0°, 15°, 30°, 45°, and 60°). Fluoroscopic images were taken after each turn during screw insertion and analyzed. Initial screw push-off, residual fracture gap at optimal fracture gap reduction, and malreduction were determined in each trial. Statistical analysis was performed via a 1-way analysis of variance followed by Student t tests.

RESULTS

Malreduction was found to be significantly different between the perpendicular (1.88 mm ± 1.38) and the oblique/longitudinal (0.58 mm ± 0.23) screws. The malreduction increased for the perpendicular screw as the fracture angle increased (60° > 45°=30° > 15° > 0°). Residual fracture gap at optimal fracture gap reduction was also found to be significantly different between the perpendicular (0.97 ± 0.42) and oblique/longitudinal (1.43 ± 1.14) screws. The residual fracture gap increased for the oblique/longitudinal screw as the fracture angle increased, although the oblique/longitudinal screw with a 60° fracture angle was the only configuration significantly larger than all the other configurations. Screw push-off was not found to be significantly different between the oblique/longitudinal screw and perpendicular screw trials.

CONCLUSIONS

The perpendicular screw had a larger malreduction that increased with fracture angle, whereas the oblique/longitudinal screw had a larger residual fracture gap that increased with fracture angle.

Mechanism of scaphoid waist fracture: finite element analysis

The mechanism of scaphoid waist fracture is not completely understood. We used finite element analysis to study the formation of scaphoid waist fractures. Clinical computed tomography scans of 12 wrists were used to create models for finite element analysis. The points of application of load were at different sites along the scaphotrapeziotrapezoid joint distally, and the scaphoid fossa plus the area underlying the radioscaphocapitate ligament was regarded as the fixed proximal support. A fracture was produced at the scaphoid waist in all cases. The location of failure of bone at its anterior or dorsal cortex, either in tension or in compression, was determined by the site of application of the load. The anterior cortex failed in compression when the point of impact was located along the trapezium facet or the entire distal pole, whereas it failed in tension when the point of impact was along the trapezoid facet.

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.

The progress in the classification and treatment of scaphoid nonunion

Scaphoid fracture is the most common carpal fracture, accounting for 50%-80% of all carpal fractures in the Youngers and manual workers. The nonunion rate of scaphoid fractures was approximately 10-15%. Scaphoid nonunion can lead to wrist deformity, wrist collapse, ischemic necrosis, and traumatic osteoarthritis resulting in the loss of wrist function and seriously influence the patients' lives. Achieving bony union is essential for the treatment of scaphoid nonunion. Although many surgical procedures including various forms of bone grafting have been developed to improve bony union, there is no conclusion about which method is the most effective and optimal. In this review, we provide an overview of the diagnostic, classification and progress in the treatments of scaphoid nonunion fractures.

Wrist Trauma: More Than Bones

Acute and subacute wrist trauma predominantly consist of fractures of the distal radius in elderly patients and most frequently carpal fractures (scaphoid, followed by triquetrum and hamatum) and avulsion fractures of the ulnar styloid in younger patients, especially in sports-related injuries but also in work activities. The initial radiographs may miss the fractures and result when untreated in complications as nonunion, osteonecrosis, and degenerative osteoarthritis.

Fractures of the distal radius and of the scaphoid may be associated with ligament injuries, most frequently the scapholunate complex, which are often overlooked at the emergency department. Patients without osseous injuries may present intrinsic and extrinsic ligament tears that may lead to carpal instability when they are clinically and/or radiologically missed.

Therefore, in acute and subacute setting, computed tomography may be helpful for the detection of subtle fractures, and magnetic resonance imaging, for the early diagnosis of occult fractures and ligament injuries.

A meta-analysis of union rate after proximal scaphoid fractures: terminology matters

Heterogeneity in the anatomical definition of 'proximal' affects the comparison of outcomes of these scaphoid fractures. This study aims to review published outcomes of all variants to determine both, differences in terminology, and union rate based upon definition. A literature search was conducted to identify articles that reported descriptions and union rate of all acute (<8 weeks of injury) proximal scaphoid fractures in adult patients (>16 years old). Proximal fractures were grouped as reported ('third', 'pole', 'fifth' or 'undefined'). The data were pooled using a fixed-effects method, and a meta-analysis was conducted to compare relative risk (RR) of non-union against non-proximal fractures. Qualitative analysis of 12 articles included three main definitions: 'proximal' (1 article), 'proximal third' (3 articles), and 'proximal pole' (8 articles). Only 6 articles adopted a specific anatomical or ratio description. In a pooled meta-analysis of union rates (15 articles), 'proximal third' and 'proximal pole' fractures demonstrated a relative risk (RR) of non-union of 2.3 and 3.4 in comparison to non-proximal fractures, respectively. Operative management yielded lower non-union rates than non-operative for all fracture types (6% vs. 18%). In conclusion, non-union risk varies depending on definition, with non-standardised classifications adding heterogeneity to reported outcomes. We recommend an approach utilizing fixed anatomical landmarks on plain radiographs (referencing scaphoid length and scapho-capitate joint) to standardise reporting of proximal fracture union in future studies. Abbreviations: CI: confidence intervals; CT: computer tomography; Df: degrees of freedom; DL: dersimonian and laird estimator; MRI: magnetic resonance imaging; NICE: national institute for health and care excellence; OTA: orthopaedic trauma association; PA: posterior-anterior; PRISMA: preferred reporting items for systematic reviews and meta analyses; RCT: randomised controlled trial; RR: relative risk; SNAC: scaphoid non-union advanced collapse; UK: United Kingdom.

Volar rerouting of the 1,2 intercompartmental supraretinacular artery vascularized bone graft for middle and distal scaphoid nonunions

BACKGROUND

The bone graft vascularized by the 1,2 intercompartmental supraretinacular artery (1,2 ICSRA) placed on the scaphoid by a dorsal approach is a technique used to treat scaphoid nonunions with avascular necrosis of the proximal pole and without significant bone loss or carpus collapse. We present the results of patients treated with a volar rerouting of the 1,2 ICSRA graft under the tendons of the first extensor compartment to treat more distal scaphoid nonunions than the proximal pole. The aim of this study was to assess the clinical and radiological outcomes of patients operated with this technique with the hypothesis that it would allow to treat more distal nonunions than those of the proximal pole.

PATIENTS AND METHODS

This retrospective study involved patients treated by a volar rerouting of the 1,2 ICSRA graft for nonunions of the middle and distal thirds of the scaphoid. Assessments included clinical outcomes and radiological bone consolidation. QuickDASH and Mayo Wrist scores were computed. Range of motion and grip strength were evaluated for both the operated and the contralateral sides.

RESULTS

Nineteen patients were followed-up for 33 months (range: 6-75). Mean postoperative QuickDASH score was 10 (range: 0-45), and mean Mayo wrist score was 85 (range: 50-100). Flexion and extension, ulnar and radial deviations were statistically different between the affected and healthy sides (p<0,05). Consolidation was achieved in 17 patients (89%).

DISCUSSION

This technical modification allowed good functional outcomes and scaphoid consolidation. It expands the classic indications of the vascularized 1,2 ICSRA bone graft to more distal nonunions than the proximal pole.

LEVEL OF EVIDENCE

IV.

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.

Diagnostic and Therapeutic Approach to Acute Scaphoid Fractures

The scaphoid is the carpal bone that most often fractures, accounting for up to 70% of carpal fractures and 11% of hand fractures. It is the second most common arm fracture, only surpassed by fractures of the distal radius. Despite being so common, these fractures can be difficult to diagnose and treat due to the anatomic and physiological particularities of the bone, including its precarious vascularization, its complex three-dimensional structure, and its ligament connections, which greatly contribute to the risk of complications such as malunion, pseudoarthrosis and avascular necrosis. Although there are many published studies on the treatment of these injuries, there is still controversy over what is the most suitable one for certain fracture types. The present article is a comprehensive and updated review of the literature. Combining strategies for clinical and radiological diagnosis, we propose a complete algorithm for the diagnosis of scaphoid fractures based on the varying availability of resources, and we also describe the most appropriate therapeutic approach for the different types of acute fractures of this bone.

3D mapping of scaphoid fractures and comminution

OBJECTIVE

Acute and subacute scaphoid fractures were assessed using 3D computer tomography (CT). The aims were to describe fracture morphology, to map fractures onto a 3D scaphoid model and to correlate this to scaphoid anatomy.

MATERIALS AND METHODS

A retrospective, multicentre database search was performed to identify CT studies of acute and subacute scaphoid fractures. CT scans of scaphoid fractures less than 6 weeks from time of injury were included in this retrospective, multicentre study. CTs were segmented and converted into three-dimensional models. Following virtual fracture reduction, fractures were mapped onto a three-dimensional scaphoid model.

RESULTS

Seventy-five CT scans were included. The median delay from injury to CT was 29 days. Most studies were in male patients (89%). Most fractures were comminuted (52%) or displaced (64%). A total of 73% of displaced fractures had concomitant comminution. Waist fractures had higher rates of comminution and displacement when compared with all other fractures. Comminution was located along the dorsal ridge and the volar scaphoid waist.

CONCLUSION

Our study is the first to describe acute fracture morphology using 3D CT and to correlate comminution and displacement to fracture types. The dorsal ridge and volar waist need prudent assessment, especially in waist fractures.

Determining diagnosis of scaphoid healing: Comparison of cone beam CT and X-ray after six weeks of immobilization

PURPOSE

To assess the accuracy and reliability of using cone beam computed tomography (CBCT) compared to X-ray six weeks after injury for predicting scaphoid union.

MATERIALS AND METHODS

Overall; 52 patients with scaphoid fractures between April 2018 and March 2019 were prospectively included in this study. The mean age was 34.52 (13-88) years, and the gender ratio male/female 43/9. Of the fractures, 26 had occurred on the right side, and 26 on the left side. In total, 28 % of patients were manual workers. All patients underwent X-ray and CBCT six weeks after injury. Four readers, two radiologists, and two hand surgeons analyzed the findings using double-blinded X-ray and CBCT and categorized fractures as consolidated based on a 50 % visibility threshold concerning trabecular bridges. Proximal pole sclerosis, communition, cyst formation, and humpback deformity were similarly analyzed for all cases. Agreement between readers was calculated using Kappa, and sensitivity, specificity, and accuracy using RStudio software. The gold standard was the radiologic and clinical follow-up for all patients at two months.

RESULTS

Inter-reader agreement between the four readers was moderate concerning X-ray (0.543) but substantial concerning CBCT (0.641). It was almost perfect between seniors regarding CBCT (Kappa = 0.862). Sensitivity, specificity, and accuracy were 0.75-0.78, 0.4, and 0.61-0.64, respectively, for two readers regarding CBCT. The X-ray values were 0.65-0.71, 0.35-0.4, and 0.53-0.59, respectively.

CONCLUSION

CBCT proves more accurate and reliable than X-ray for diagnosing scaphoid union at an early follow-up and prevents longer immobilization and interruption of activity or work.

Conservatively Managed, Displaced Scaphoid Fracture in a Young, Female Collegiate Basketball Player

Fractures of the scaphoid bone occur in 60-70% of wrist bone fractures. It most often occurs after a fall onto outstretched hand injury. Many times, the diagnosis of a scaphoid fracture is missed due to the unique anatomy and positioning of this carpal bone. Treatment options vary depending on the type of fracture and degree of displacement. We present the case of a 19-year-old female patient. She reported to the urgent care facility after a fall on an outstretched hand while playing basketball. She was diagnosed with a wrist sprain. After having continued pain she sought care at the sports medicine clinic where she was diagnosed with a displaced scaphoid fracture. She was managed conservatively with thumb-spica casting and later adjuvant therapy treatments with low-intensity pulsed ultrasound (LIPUS) technology.

Volar Scaphoid Plating for Nonunion: A Multicenter Case Series Study

Background  The volar scaphoid plate from Medartis (Medartis AG, Austrasse, Basel, Switzerland) is a variable angle titanium locking plate, preformed for the volar aspect of the scaphoid. It does not have compressive capability, and may act as a bridging device. It may provide an advantage over a compression screw where the pathoanatomy is less favorable to such a device with increased rotational stability. It may act as a buttress plate for correction of humpback deformity for example. It has been used in nonunions and with vascularized grafts. Questions  Our study aims to assess the results of our patients with scaphoid nonunion treated with scaphoid volar plating over a larger number of patients. We aim to identify techniques to increase the success of plating. Methods  Patients from our cohort were retrospectively reviewed. Operations were performed by three hand fellowship trained surgeons and in two centers. Inclusion involved a scaphoid plate procedure for a nonunion of the scaphoid with a minimum of 6 months of follow-up. Exclusions were those who had less than 6 months of follow-up. Data included demographics, patient-rated wrist evaluation (PRWE), a quick disabilities of the arm, shoulder, and hand (qDASH), visual analogue score, and range and grip. Radiology was reviewed. Results  Thirty-two eligible patients were assessed. The mean age was 25 years (range 13-46), 2 were female and 15 were smokers. Mean follow-up postsurgery was 18 months. Twenty-nine of 32 patients united (90.6%) on computed tomography scan. Clinical assessment was performed in the 25 patients. The mean qDASH score was 12.5 (range 0-42) and mean PRWE was 11 (range 0-54). The mean arc of motion was 115 degrees. The mean grip strength was 39 kg compared with 41 kg on the nonoperated side. Conclusion  We postulate that the plate acts like an internal bridging device, acting over a small distance, and inherent stability of the construct with structural graft and accurate reduction prior to plating is advantageous. Potential problems include plate impingement on the volar lip of the radius, particularly when trying to plate more proximal fractures. Ideally, it is utilized for mid to distal waist fractures.

Acute scaphoid fractures: guidelines for diagnosis and treatment

In cases of suspected scaphoid fracture where the initial radiographs are negative, a supplementary MRI, or alternatively CT, should be carried out within three to five days.

Fracture classification, assessment of dislocation as well as evaluation of fracture healing is best done on CT with reconstructions in the coronal and sagittal planes, following the longitudinal axis of the scaphoid.

After adequate conservative management, union is achieved at six weeks for approximately 90% of non-displaced or minimally displaced (≤ 0.5 mm) scaphoid waist fractures.

Scaphoid waist fractures with moderate displacement (0.5–1.5 mm) can be treated conservatively, but require prolonged cast immobilization for approximately eight to ten weeks.

Internal fixation is recommended for all scaphoid waist fractures with dislocation ≥ 1.5 mm.

Distal scaphoid fractures can be treated conservatively. The majority heal uneventfully after four to six weeks of immobilization, depending on fracture type.

In general, proximal scaphoid fractures should be treated with internal fixation.

Cite this article: EFORT Open Rev 2020;5:96-103. DOI: 10.1302/2058-5241.5.190025

Scaphoid Fracture Patterns-Part One: Three-Dimensional Computed Tomography Analysis

Objective  Using three-dimensional (3D) computed tomography models of acute scaphoid fractures, we looked for differences between volumetric size of the fracture fragments, recognizable groups, or a shared common fracture area. Methods  We studied 51 patients with an adequate computed tomography scan of an acute scaphoid fracture using 3D modeling. Fracture surfaces were identified and fragment volumetric size of the fracture fragments was measured. A principal component analysis was used to find groups. Density mapping was used to image probable common fracture areas in the scaphoid. Results  Forty-nine of 51 fractures had a similar pattern. It was not possible to identify subgroups based on fracture pattern. The mean volumetric size of the fracture fragments of the proximal (1.45 cm ³  ± 0.49 cm ³ standard deviation [SD]) and distal fracture fragments (1.53 cm ³  ± 0.48 cm ³ SD) was similar. There was a single common fracture area in the middle third of the bone. In the distal third, there were no horizontal fractures through-but only directly proximal to-the tubercle suggesting that these would be best classified as distal waist fractures. Conclusion  Acute scaphoid fractures mainly occur in the middle third of the bone and tend to divide the scaphoid in half by volumetric size of the fracture fragments. There were two distinct grouping patterns: fractures through the proximal and middle third were horizontal oblique, whereas fractures of the distal third were vertical oblique. It seems that scaphoid fractures might be classified into proximal pole fractures, a range of waist fractures, and tubercle avulsion fractures. Level of evidence  This is a Level IV study.

Scaphoid Fracture Patterns-Part Two: Reproducibility and Demographics of a Simplified Scaphoid Fracture Classification

Objective  To analyze the reproducibility, reliability, and demographics of a simplified anatomical scaphoid fracture classification based on posteroanterior radiographs using a large database of scaphoid fractures. Methods  The study consisted of a retrospective review of electronic medical records of 871 consecutive patients. All patients presented between 2003 and 2014 at two centers. Patient- and surgeon-related factors were analyzed. Additionally, interobserver reliability of the Herbert and simplified scaphoid fracture classifications were tested. Results  Proximal pole fractures were defined as fractures in which the center of the fracture line was proximal to the distal scapholunate interval (n = 30), waist fractures (n = 802) were defined as fractures involving the scaphocapitate interval, and distal tubercle fractures (n = 39) were defined as fractures involving the scaphotrapeziotrapezoid (STT) interval. The interobserver reliability of the simplified classification was fair (κ = 0.37) as for the Herbert classification (κ = 0.31). The average doubt of the answers of the observers was 2.1 on a scale from 0 to 10 for the simplified classification and 3.6 for the Herbert classification ( P  < 0.05). Conclusions  All complete fractures across the entire scaphoid distal to the scapholunate articulation and proximal to the STT joint can be classified as waist fractures; nonwaist scaphoid fractures are uncommon (6%) and have somewhat different presentations compared to waist fractures. Simplifying the fracture classification slightly improves interobserver reliability, although remaining fair, and significantly reduces doubt. Level of Evidence  This is a Level III, prognostic study.

A Narrative Review on Avulsion Fractures of the Upper and Lower Limbs

Avulsion fractures compromise function and movement at the affected joint. If left untreated, it can lead to deformity, nonunion, malunion, pain, and disability. The purpose of this review was to identify and describe the epidemiology and available treatment options for common avulsion fractures of the upper and lower extremities. Current evidence suggests that optimal treatment is dependent on the severity of the fracture. Conservative efforts generally include casting or splinting with a period of immobilization. Surgery is typically indicated for more severe cases or if nonoperative treatments fail; patient demographics or preferences and surgeon experience may also play a role in decision making. Some avulsion fractures can be surgically managed with any one of various techniques, each with their own pros and cons, and often there is no clear consensus on choosing one technique over another; however, there is some research suggesting that screw fixation, when possible, may offer the best stability and compression at the fracture site and earlier mobilization and return to function. Physicians should be mindful of the potential complications associated with each intervention.

Interobserver Variability of the Diagnosis of Scaphoid Proximal Pole Fractures

Purpose  Fractures of the proximal pole of the scaphoid are prone to adverse outcomes such as nonunion and avascular necrosis. Distinction of scaphoid proximal pole fractures from waist fractures is important for management but it is unclear if the distinction is reliable. Methods  A consecutive series of 29 scaphoid fractures from one tertiary hospital was collected consisting of 5 scaphoid proximal pole and 24 scaphoid waist fractures. Fifty-seven members of the Science of Variation Group (SOVG) were randomized to diagnose fracture location and displacement by using radiographs alone or radiographs and a computed tomography (CT) scan. Results  Observers reviewing radiographs alone and observers reviewing radiographs and CT scans both had substantial agreement on fracture location (κ = 0.82 and κ = 0.80, respectively; p  = 0.54). Both groups had only fair agreement on fracture displacement (κ = 0.28 and κ = 0.35, respectively; p  = 0.029). Conclusion  Proximal pole fractures are sufficiently distinct from proximal waist fractures that CT does not improve reliability of diagnosis. Level of Evidence  Level IV interobserver reliability case-control study.

Simultaneous Fractures of the Ipsilateral Scaphoid and Distal Radius

Background  Ipsilateral fractures of the distal radius and scaphoid are rare, with few reports describing mechanisms of injury, fracture patterns, and treatment approaches. Purpose  This article describes the clinical and radiographic features of ipsilateral distal radius and scaphoid fractures occurring simultaneously. Materials and Methods  Electronic databases from 2007 to 2017 at a single Level 1 trauma center were reviewed for patients with concurrent fractures of the distal radius and scaphoid. Patient demographics, injury mechanism, scaphoid and distal radius fracture pattern, treatment approach, and radiographic healing were studied. Results  Twenty-three patients were identified. Nineteen of the 23 (83%) were males, and 19 of 23 (83%) of the injury mechanisms were considered high energy. Twenty-two of the 23 (96%) scaphoid fractures were nondisplaced, all treated with screw fixation. Most distal radius fractures were displaced and comminuted, 17 of 23 (74%) were intra-articular. All distal radius fractures were treated surgically with internal and/or external fixation. Three patients were lost to follow-up. Average follow-up of the remaining 20 was to 19.8 weeks. Nineteen of the 20 (95%) scaphoids healed, one scaphoid went on to nonunion with avascular necrosis. All 20 radius fractures healed, 16 of 20 (80%) in anatomic alignment. Conclusion  Ipsilateral fractures of the distal radius and scaphoid are rare and are usually result of high-energy mechanisms. The scaphoid fracture is usually a nondisplaced fracture at the waist. The distal radius fracture pattern varies but most are displaced and comminuted. The union rate of the scaphoid is high, even if subjected to radiocarpal distraction required for distal radius management. Level of Evidence  Therapeutic level IV study.

A new acute scaphoid fracture assessment method: a reliability study of the 'long axis' measurement

Background

The aim of this study was to assess the inter observer and intra observer reliability of acute scaphoid fracture classification methods including a novel ‘long axis’ measurement, a simple method which we have developed with the aim of improving agreement when describing acute fractures.

Methods

We identified sixty patients with acute scaphoid fractures at two centres who had been investigated with both plain radiographs and a CT (Computed Tomography) scan within 4 weeks of injury. The fractures were assessed by three observers at each centre using three commonly used classification systems and the ‘long axis’ method.

Results

Inter observer reliability: based on X-rays the ‘long axis’ measurement demonstrated substantial agreement (Intraclass Correlation Coefficient (ICC) =0.76) and was significantly more reliable than the Mayo (p < 0.01), the most reliable of the established classification systems with moderate levels of agreement (kappa = 0.56). Intra observer reliability: the long axis measurement demonstrated almost perfect agreement whether based on X-ray (ICC = 0.905) or CT (ICC = 0.900).

Conclusions

This study describes a novel pragmatic ‘long axis’ method for the assessment of acute scaphoid fractures which demonstrates substantial inter and intra observer reliability. The ‘long axis’ measurement has clear potential benefits over traditional classification systems which should be explored in future clinical research.

Analysis of instability patterns in acute scaphoid fractures by 4-dimensional computed tomographic imaging - A prospective cohort pilot study protocol

Introduction

A scaphoid fracture is the most common carpal fracture. When healing of the fracture fails (nonunion), a specific pattern of osteoarthrosis occurs, resulting in pain, restricted wrist motion and disability. Scaphoid fracture classification systems recognize fragment displacement as an important cause of nonunion. The fracture is considered unstable if the fragments are displaced. However, whether and how displaced bone fragments move with respect to one another has not yet been investigated in vivo. With a four-dimensional (4D) computed tomographic (CT) imaging technique we aim to analyze the interfragmentary motion patterns of displaced and non-displaced scaphoid fragments. Furthermore, the correlation between fragment motion and the development of a scaphoid nonunion is investigated. We hypothesize that fragment displacement is not correlated to fragment instability; and concurrent nonunion is related to fragment instability and not to interfragmentary displacement.

Methods

In a prospective single-center cohort pilot study, patients with a one-sided acute scaphoid fracture and no history of trauma to the contralateral wrist are illegible for inclusion. Twelve patients with a non-displaced scaphoid fracture and 12 patients with a displaced scaphoid fracture are evaluated. Both wrists are scanned with 4D-CT imaging during active flexion-extension and radio-ulnar deviation motion. The contralateral wrist serves as kinematic reference. Relative displacement of the distal scaphoid fragment with respect to the proximal scaphoid fragment, is described by translations and rotations (the kinematic parameters), as a function of the position of the capitate. Non-displaced scaphoid fractures are treated conservatively, displaced scaphoid fractures receive intraoperative screw fixation. Follow-up with CT scans is conducted until consolidation at 1½, 3 and 6 months. This trial is registered in the Dutch Toetsingonline trial registration system, number: NL60680.018.17.

Ethics

This study is approved by the Medical Ethics Committee of the Academic Medical Center, Amsterdam.

Management of Scaphoid Fractures

LEARNING OBJECTIVES

After reading this article, the participant should be able to: 1. Understand the epidemiology, classification, and anatomy pertinent to the scaphoid. 2. Appropriately evaluate a patient with suspected scaphoid fracture, including appropriate imaging. 3. Understand the indications for operative treatment of scaphoid fractures, and be familiar with the various surgical approaches. 4. Describe the treatment options for scaphoid nonunion and avascular necrosis of the proximal pole.

SUMMARY

The goal of this continuing medical education module is to present the preoperative assessment and the formation and execution of a surgical treatment plan for acute fractures of the scaphoid. In addition, secondary surgical options for treatment of scaphoid nonunion and avascular necrosis are discussed.

[Fractures of carpal bones]

Fractures of the carpal bones are uncommon. On standard radiographs fractures are often not recognized and a computed tomography (CT) scan is the diagnostic method of choice. The aim of treatment is to restore pain-free and full functioning of the hand. A distinction is made between stable and unstable carpal fractures. Stable non-displaced fractures can be treated conservatively. Unstable and displaced fractures have an increased risk of arthritis and non-union and should be stabilized by screws or k‑wires. If treated adequately, fractures of the carpal bones have a good prognosis. Unstable and dislocated fractures have an increased risk for non-union. The subsequent development of carpal collapse with arthrosis is a severe consequence of non-union, which has a heterogeneous prognosis.