Accuracy of the skyline view for detecting dorsal cortical penetration during volar distal radius fixation

Avoiding screw overlength using dorsal horizon view in palmar plate osteosynthesis of distal radius fractures: a prospective randomized trial

INTRODUCTION

Distal radius fractures are the most commonly reported fractures in adults. Treatment has changed in recent years to open reduction and palmar plate fixation. Penetration of the dorsal screw, however, is a well-known complication. Intraoperative anteroposterior and lateral radiographs lack the exact assessment of dorsal screw length and intraoperative measurement is therefore very likely to be inaccurate in a comminuted dorsal radial cortex. Secondary extensor tendon ruptures are reported in up to 6% following palmar plate fixation of distal radius fracture.

MATERIALS AND METHODS

A prospective randomized trial was performed to assess the value of the dorsal horizon view. The hypothesis was that the traditional anteroposterior and lateral fluoroscopic views aided by an axial view of the dorsal part of the radius, named dorsal horizon view, could prevent dorsal screw penetration. A total of 40 patients, 6 male and 34 female, were included in the study. Standardized anteroposterior and lateral radiographs were performed intraoperatively in 18 patients (standard group = control group). In 22 patients, intraoperative axial fluoroscopic views (dorsal horizon view) were added to anteroposterior and lateral images (horizon group). Numbers of intraoperative screw changes due to the two different radiological examinations were analyzed as well as exact postoperative CT guided measurement of screw length.

RESULTS

The total numbers of intraoperative screw changes were significantly higher in the horizon group. Forty-two screws were changed in 15 patients in the horizon group while only 8 screws were changed in 3 patients in the standard group. Postoperative computed tomography scans showed significantly lower total numbers of perforating screws in the horizon group with 11 screws in 22 patients compared to 20 screws in 18 patients in the standard group (p = 0.02).

CONCLUSIONS

Based on the results of this study, the dorsal horizon view improves the assessment of the correct screw length and should routinely be used in palmar plate osteosynthesis of distal radius fractures. Since screw protrusion cannot be absolutely ruled out using the dorsal horizon view, monocortical drilling or screw downsizing is still mandatory.

TRIAL REGISTRATION

This clinical trial was not registered because it was a clinical examination without any experimental techniques.

LEVEL OF EVIDENCE: 2

[Possibilities and limits of intraoperative 2D imaging in trauma surgery]

BACKGROUND

The two-dimensional (2D) imaging represents an essential and cost-effective component of intraoperative position control in fracture stabilization, even in the era of new three-dimensional (3D) imaging capabilities.

OBJECTIVE

The aim of the present study, in addition to a current literature review, was to examine whether the intraoperative use of 2D images leads to a quality of fracture reduction comparable to postoperative computed tomographic (CT) analysis including 3D reconstructions.

MATERIAL AND METHODS

A comparative retrospective analysis of intraoperative 2D and postoperative 3D image data was performed on 21 acetabular fractures stabilized via a pararectus approach according to an established protocol using the Matta criteria.

RESULTS

The assessment of fracture reduction in intraoperative fluoroscopy compared with postoperative CT revealed a difference only in one case with respect to the categorization of the joint step reduction in the main loading zone.

CONCLUSION

In the intraoperative use of 2D imaging for fracture treatment it is important to select the correct adjustment planes taking the anatomical conditions into account in order to achieve optimum assessability. In this way, the reduction result can be adequately displayed in fluoroscopy and is also comparable to the postoperative CT control. In addition, depending on the findings, optional intraoperative dynamic fluoroscopic assessment can have a direct influence on the further surgical procedure.

Computed Tomography Evaluation of Distal Screw Penetration in Volar Locking Plate Fixation for Intra-Articular Distal Radius Fractures

PURPOSE

Volar locking plate fixation for distal radius fractures (DRFs) is a technically demanding procedure with a risk of distal screw penetration through the dorsal cortex or the articular surface. This study aimed to investigate the incidence and details of distal screw penetration after volar locking plate fixation for intra-articular DRFs using a CT scan and to evaluate the relationship between the incidence of screw penetration and fracture comminution severity and the clinical complications of screw penetration.

METHODS

This was a retrospective case series of 91 adult patients (mean age, 63 years; 27 men) who underwent volar locking plate fixation for intra-articular DRFs from 2015 to 2018. The positioning of the distal screws was evaluated using a postoperative CT scan, and radiological outcomes were compared between the AO C1 and C3 groups. At the final follow-up, tendon rupture and arthritis severity were assessed as clinical complications of dorsal and intra-articular screw penetration.

RESULTS

Distal screw penetration was observed in 44 wrists (48%), dorsal cortex screw penetration in 34, intra-articular screw penetration in 13, and both dorsal cortex and intra-articular screw penetration in three. The incidence of intra-articular screw penetration was significantly higher in the C3 group than in the C1 group. No tendon rupture was observed. Multivariable analysis revealed that intra-articular screw penetration was significantly related to high severity of arthritis.

CONCLUSIONS

Approximately half of the study patients with intra-articular DRFs had distal screw penetration. The incidence of intra-articular screw penetration was associated with the severity of fracture comminution, and the intra-articular screw penetration was associated with the incidence of early radiocarpal arthritis. Intra-articularly penetrating screws should be replaced as soon as they are discovered, regardless of the length of penetrated screw or absence of patients' subjective symptoms.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Comparison of ultrasound and dorsal tangential view for dorsal cortex screw penetration in volar plating of the distal radius

We compared the accuracy of the fluoroscopic dorsal tangential view (DTV) and an ultrasound (US) examination in detecting dorsal screw penetration during volar distal radius plating. In six fresh cadaveric distal radii, seven periarticular locking screws in two rows for each plate were inserted according to the measured length using a depth gauge and then replaced with another that was 1 and 2 mm longer, respectively. The actual protruded length of each screw was determined using computed tomography (CT) images. The accuracy of US and DTV measurements was determined using the intraclass correlation coefficient (ICC), as both measurements were compared with CT measurements. The ICC of US and DTV was 0.96 and 0.75, respectively, for all screws. After excluding the data for proximal-row screws, the ICC of US remained unchanged at 0.96, and that of DTV improved to 0.86. The ICC of US was significantly higher than that of DTV (p < 0.01). US had a 100% detection rate for screw protrusion of more than 1.0 mm. US examination showed excellent consistency with CT measurements and its accuracy was not affected by screw location. US might thus be a practical tool for detecting dorsal cortex screw penetration during volar distal radius plating.

Evaluation of Ulnar Setting of Volar Locking Plates for Distal Radius Fractures Using Modified Skyline View

Purpose

Volar lunate facet fragments in distal radius fractures are located at the center of the load in the wrist joint and, therefore, should be properly supported by the distal ulnar setting of volar locking plates to obtain better postoperative outcomes. This study evaluated the usefulness of the modified skyline view (MSV) in intraoperative fluoroscopy for the ulnar setting of volar locking plates by comparing it with that of the anteroposterior view (APV).

Methods

Sixty-five patients with distal radius fractures who underwent open reduction and plate fixation as well as follow-up intraoperative fluoroscopy and postoperative computed tomography (CT) at our institution between April 2019 and March 2022 were included. The distance between the ulnar edge of the plate and the distal radius (d-value) was measured retrospectively using intraoperative fluoroscopy (distance measured from MSV and distance measured from APV) or postoperative CT (distance measured using postoperative CT). The distance measured from MSV and that measured from APV were compared with those measured using CT as the true values. Each measurement was performed twice by 2 examiners at an interval of 1 month. The comparison scores were evaluated using the intraclass correlation coefficient.

Results

The distance measured from MSV showed a difference of 0.6 ± 0.5 mm from that measured using CT, which was significantly smaller than that measured from APV (1.2 ± 0.9 mm; P < .001). Neither postoperative volar subluxation nor dislocation of bone fragments was found during the study period. Both intraclass correlation coefficient (1,1) and intraclass correlation coefficient (2,1) reliabilities were substantial to almost perfect.

Conclusions

Modified skyline view is an effective and versatile imaging method for estimating the ulnar setting of volar locking plates; it provides measurements more similar to those provided by postoperative CT compared with APV. The use of MSV may reduce postoperative complications, such as volar subluxation and dislocation of bone fragments, especially in cases with volar lunate facet fragments in which the ulnar setting of the plate is significant.

Type of study/level of evidence

Diagnostic III.

[Claims following distal Radius Fractures]

BACKGROUND

As distal radius fractures as well as diagnostic and therapeutic options vary widely, there is an enormous potential for deficient convalescence and subsequent patient dissatisfaction. The aim of this study is the evaluation of malpractice in distal radius fracture management, which could help to draw conclusions regarding optimization and prevention as well as raising patient satisfaction and minimizing subsequent costs.

MATERIAL AND METHODS

Files and patient data of all distal radius fracture complaints regarding one public hospital operator in a period between 2007 and 2017 were reviewed and subjected to descriptive statistics.

RESULTS

A total of 35 cases with complaints regarding medical treatment, communication and long-term effects were identified, broken down into key issues and analyzed by means of descriptive statistics.

CONCLUSION

Complications and long-term effects of distal radius fractures are not completely avoidable. It is possible, however, to prevent lack of communication and treatment delays. To achieve increased patient satisfaction, it is essential to reflect on diagnostic, therapeutic and interpersonal strategies.

Distal radius fracture fixation using volar plate: A comparative study evaluating the biomechanical behavior of uni and bicortical distal screws

Extensor tendon ruptures caused by bicortical screws impingement following distal radius fracture fixation with volar plates are extensively reported in the literature. Thus, a biomechanical study comparing unicortical and bicortical fixations in intra-articular distal radius fracture models is critical in decision-making regarding distal radius fracture management. Forty-two synthetic radius models were fixed using a variable angle volar distal locking plate with seven screws. They were divided into 6 groups (n = 7): G1/G3/G4 unicortical fixation (75% of anteroposterior distal radius lenght); G2/G4/G6 bicortical fixation. Each group underwent a different mechanical test: axial compression (G1/G2), dorsal flexion (G3/G4), and volar flexion (G5/G6). The load application rate was 5 mm/min and 1000 cycles of 50 to 250 N at 1 Hz were performed between both static tests. Comparative results in the first static test, in the second static test, and in failure generally showed a very similar behavior. Models depicted similar behavior in the second static test when cyclic load was performed. Therefore, one can realize that stiffness differed during dorsal flexion only in the first static test. Maximum force to break the model in axial compression was greater in bicortical than in unicortical construct. Since biomechanical properties are similar, we recommend using unicortical distal locking screws in distal radius fracture fixation with volar plates to prevent extensor tendon ruptures.

Fluoroscopy of the Elbow: A Cadaveric Study Defining New Standard Projections to Visualize Important Anatomical Landmarks

Background

Despite new 3-dimensional imaging modalities, 2-dimensional fluoroscopy remains the standard intraoperative imaging modality. The elbow has complex anatomy, and defined standard fluoroscopic projections are lacking. Therefore, the aim of this study was to define standard projections of the elbow for intraoperative fluoroscopy.

Methods

This study consisted of 2 parts. In part I, dissected cadaveric elbows were examined under fluoroscopy, and their radiographic anatomical features were assessed, with focus on projections showing defined anatomical landmarks. In part II, projections from part I were verified on entire cadavers to simulate intraoperative imaging. Standard projections for anteroposterior (AP) and lateral views as well as oblique and axial views were recorded.

Results

Eight standardized projections could be defined and included 3 AP, 1 lateral, 2 oblique, and 2 axial views. By applying these specific projections, we could visualize the epicondyles, the trochlea with its medial and lateral borders, the capitellum, the olecranon, the greater sigmoid notch, the coronoid process including its anteromedial facet, the proximal radioulnar joint with the radial tuberosity, and the anterior and posterior joint lines of the distal part of the humerus. These standard projections were reliably obtained using a specific sequence.

Conclusions

Knowledge about radiographic anatomy and standard projections is essential for visualizing important landmarks. With the presented standard projections of the elbow, important anatomical landmarks can be clearly examined. Thus, fluoroscopic visualization of anatomical fracture reduction and correct implant placement should be facilitated.

Clinical Relevance

This basic science cadaveric study defines fluoroscopic standard projections of the elbow essential for visualization of anatomical landmarks during surgery.

Systematic use of short unicortical epiphyseal locking screws versus full-length unicortical locking screws in distal radius fracture volar plating: A prospective and comparative study

PURPOSE

Volar locking plates, used in distal radius fracture (DRF), present a risk of injuring extensor tendons with screws penetrating the dorsal cortex of the radius. Actually, even when aiming to use maximum-length unicortical locking screws, some still could be bicortical. We hypothesize the use of only short unicortical screws would allow a proper stabilization of the radial epiphysis without the risk of dorsal cortex penetration.

MATERIALS AND METHODS

A prospective monocentric non-randomized study was conducted. Patients with DRF (excepted for partial dorsal joint fractures) were treated in group A with short locking epiphyseal screws (16 mm for females, 18 mm for males) and in group B with full-length unicortical locking screws. Ultrasound was done 3 months postoperatively to evaluate the number and length of prominent dorsal screws. X-rays were performed after 6 weeks to assess stability according to volar tilt and radial inclination variations.

RESULTS

There were 37 patients in group A and 39 in group B with 148 and 156 epiphyseal screws, respectively. In group A, there were 0% of dorsal penetrating screws against 6.5% (10 screws from 8 patients) in group B (p < 0.05). There was no significant difference for the stability between the groups: mean volar tilt variation ( - 0.6° vs. - 0.7°) and mean radial inclination variation ( - 0.4° vs. - 0.4°).

CONCLUSION

For a same stability with volar locking plates for DRF, short epiphyseal locking screws should be preferred to full-length unicortical screws in order to prevent extensor tendon injuries. Based on 75% of distal radial average anteroposterior width for each sex, screw lengths of 16 mm for females and 18 mm for males seem to be the length to use. LEVEL OF EVIDENCE 2: Prospective, Comparisons made, non-randomized.

Influence of training on dorsal tangential radiographic view to detect screw protrusion after anterior plating of the distal radius: a cadaveric study

In this cadaveric study of anterior plating of the distal radius, we aimed to determine the interobserver agreement and diagnostic performance for detecting dorsally protruding screws using the dorsal tangential radiographic view before and after specific training. Without prior instruction, 13 observers interpreted the dorsal tangential view of cadaveric specimens, in which anterior radial plates were placed. After seeing a training video on the dorsal tangential view, they repeated the task. Though we found that accuracy and interobserver agreement was lower than described in some other clinical series, training led to statistically significant improvements of (1) the interobserver agreement on the decision to exchange screws, (2) the self-confidence of the surgeon in obtaining adequate views, and (3) the number of fluoroscopic images required to obtain these views. After training, the number of protruding screws missed was reduced by 36%, but 7% of dorsally protruding screws was still missed.

A 2-free-end flexor carpi radialis tendon graft for treating a complex index finger extensor tendon injury

Background:

Volar plating has increasingly become the most used technique for the treatment of unstable distal radius fractures due to the low soft-tissue disturbance and its biomechanical reliability, which allows the early mobilization of the wrist. One of the main goals of the volar locking compression plates design is to avoid those soft tissue complications historically associated to the dorsal plating. However, extensor tendon complications can not be completely excluded.

Method:

The authors report the case of a patient with a complete rupture of the index finger extensor tendons after volar plate fixation of the distal radius. Due to the presence of a severe tendons retraction with a 4-centimeter gap and the neighbouring soft tissues damage, it was decided to fill the gap with a 2-free-end autograft harvested from the Flexor Carpi Radialis (FCR) tendon, using the volar surgical approach performed to remove the plate.

Results:

At the 2-month follow-up, the patient showed the complete recovery of the flexion-extension movements.

Conclusions:

Even though the 2-free-end FCR tendon graft is not commonly reported for the reconstruction of extensor tendons defects, we assume it deserves to be considered as an adequate technique whenever the neighbouring tendons are critically compromised. (www.actabiomedica.it)

Predicting epiphyseal screw length in anterior plating of distal radial fractures

The purpose of this study was to determine whether optimal epiphyseal screw length could be predicted with reference to a given diaphyseal screw length when fixating a plate to the anterior surface of the distal radius. Computerized tomography scans of 40 wrists of 28 men and 12 women were semi-automatically segmented. A virtual anterior plate model was fixed to the distal radius. The mean maximal appropriate length of one diaphyseal screw and of the four distal epiphyseal screws were measured and linear regression analyses were performed. We found that the epiphyseal screw lengths were highly correlated to the diaphyseal screw length. Based on the data derived from measurements, we recommend epiphyseal screw lengths from ulnar to radial of 18, 18, 20 and 16 mm, respectively, if the diaphyseal screw is 14 mm or less. For diaphyseal screws longer than 14 mm we recommend epiphyseal screws of 20, 20, 22 and 18 mm. Using these recommended screw lengths as general guidelines may reduce the risk of intra-operative and postoperative extensor tendon injury.

Radiological results of surgical management of fracture of the distal radius treated with volar locking plates

OBJECTIVES

Distal radius fracture (DRF) is the most common upper extremity fracture. The incidence of complications after surgical treatment still remains high. The objective of our study was to assess functional and radiological results of DRF treated with volar locking plate.

METHODS

We conducted a retrospective study including DRF treated by open reduction and internal fixation with a volar locking plate during a period of 8 years (2010-2018). Data were collected from clinical records and included patient demographics, fracture characteristics, radiological parameters (radial inclination, palmar tilt, ulnar variance, articular step-off), range of motion (ROM), complications and reinterventions.

RESULTS

A total of 170 patients (63.5% female) met the inclusion criteria with a mean age of 55.9 years [24.1-83.7; 13.76]. High energy injuries were more frequent in younger patients (25.56% vs 3.95%; p < 0.0001). AO classification was: 2R3A: 23.5%, 2R3B: 24.1% and 2R3C: 52.4%. Time until surgery was 8.5 days, longer in extraarticular fractures (AO-2R3A: 12.22 days, AO-2R3B: 7.97 days, AO-2R3C: 7.04 days, p = 0.018). Younger patients had better radial inclination (excellent in 85.1% vs 59.21%, p = 0.001) and radial shortening (excellent in 100% vs 88.15%, p = 0.001). ROM was: flexion 63° [0-90°; 19.73], extension 57.67° [5-90°; 21.61], pronation 78.94° [40-90°] and supination 81.76° [38-90°; 8.87]. We found a weak correlation between ROM in flexion-extension and radial shortening (r = 0.218; p = 0.001) and articular step-off (r = -0.269; p = 0.002). We had 39 complications (21.18% of patients). 10.6% of patients needed a re-operation, being the most frequent hardware removal (6.5%) and tendinous disruptions repairs (2.4%). Reintervention rate was higher in younger patients (14.9% vs 5.3%; p = 0.042), complete articular fractures (AO-2R3A: 2.5%; AO-2R3B: 7.3%; AO-2R3C: 15.7%; p = 0.037) and high energy injuries (8.4% vs 22.2%; p = 0.044). Patients undergoing reintervention had a decreased flexion-extension (94.44° vs 123.83°, p = 0.007).

CONCLUSION

Radial shortening and articular step-off seem the most important predictors for postoperative range of motion. Worse radiological outcomes are observed in complete articular fractures and those affecting elder population. Although radiological and functional results are good or excellent in most of cases, the incidence of complications and need for reintervention still remains noticeable. Re-operations were more frequent in younger patients, complete articular fractures and high energy injuries, and it worsened functional outcomes.

Detection of dorsal screw penetration during volar plating of the distal radius fractures: A comparison of different fluoroscopic views and screw sizes

OBJECTIVE

The objective of this study was to compare different screw lengths combined with different fluoroscopic views to detect intraoperative dorsal screw penetration in distal radius fractures treated with volar locked plating.

MATERIAL AND METHODS

From April 2014 to October 2018, one hundred and eighty patients were included. We divided the patients into four groups. Intraoperative AP and lateral views were taken and sizes of the screws were chosen based on actual measurement (Group A, 45 patients). AP, lateral and tangential views were taken and sizes of the screws were also chosen based on actual measurement (Group B, 45 patients). Intraoperative AP and lateral views were taken and the selected screws were 2mm shorter than actual measurement (Group C, 45 patients). AP, lateral and tangential views were taken and the selected screws were 2mm shorter than actual measurement (Group D, 45 patients). Prominent screws were changed intraoperatively according to each view. A computed tomography (CT) was taken postoperatively to identify residual prominent screws.

RESULTS

The number of dorsally prominent screws exceeding 1mm was 6 of 301 in Group A (2.0%), 15 of 290 (5.2%) in Group B, 2 of 289 in Group C (0.7%), and 2 of 282 (0.7%) in Group D. All these prominent screws (25 screws) were exchanged for shorter screws during surgery. Group A and Group B had significant difference in detecting intraoperative dorsal screw penetration (p<0.05). Group C and Group D had no significant difference in detecting intraoperative dorsal screw penetration (p>0.05). Postoperative CT identified 12 additional prominent screws with≥1mm dorsal penetration in Group A, 2 screws in Group B, 1 screw in Group C and 0 screw in Group B respectively. Significant difference was found between Group A and Group B of CT results (p<0.05) while no statistical difference was found between Group C and Group D of CT results (p>0.05).

DISCUSSIONS

Tangential view helped identify screw penetration. If tangential view was not available intraoperatively, screw penetration could also be avoided by downsizing the distal locking screw by 2mm shorter than actual measurement.

Volar Plating: Imaging Modalities for the Detection of Screw Penetration

Background  Volar plating for distal radius fractures exposes the risk of extensor tendon rupture, mechanical problems, and osteoarthritis due to protruding screws. Purposes  The purpose of this review was to identify the best intraoperative diagnostic imaging modality to identify dorsal and intra-articular protruding screws in volar plating for distal radius fractures. Methods  The Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were followed for this review. In vitro and in vivo studies that analyzed the reliability, efficacy, and/or accuracy of intraoperatively available imaging modalities for the detection of dorsal or intra-articular screw protrusion after volar plating for distal radius fractures were included. Results  Described additional imaging modalities are additional fluoroscopic views (pronated views, dorsal tangential view [DTV], radial groove view [RGV], and carpal shoot through [CST] view), three-dimensional (3D) and rotational fluoroscopies, and ultrasound (US). For detection of dorsal screw penetration, additional fluoroscopic views show better results than conventional views. Based on small (pilot) studies, US seems to be promising. For intra-articular screw placement, 3D or 360 degrees fluoroscopy shows better result than conventional views. Conclusion  Based on this systematic review, the authors recommend the use of at least one of the following additional imaging modalities to prevent dorsal protruding screws: CST view, DTV, or RGV. Tilt views are recommended for intra-articular assessment. Of all additional fluoroscopic views, the DTV is most studied and proves to be practical and time efficient, with higher efficacy, accuracy, and reliability compared with conventional views. Level of Evidence  The level of evidence is Level III.

Biomechanical considerations for strategies to improve outcomes following volar plating of distal radius fractures

This article is a systematic review of the recent published literature on the biomechanics of volar locking plate fixation of distal radius fractures. PUBMED/MEDLINE and EMBASE databases were searched on 13th Sep 2018. Biomechanical papers on volar locking plate fixation of distal radius fractures since 2010 were included. Papers were analysed and included studies were appraised by the author using the validated quality assessment GRADE tool. The search revealed 456 papers between January 2010 and the present day whose abstracts were reviewed for relevance and 21 papers were included for full paper review. The aim of this systematic review was to evaluate the evidence to determine the surgical techniques and strategies that are associated with the best biomechanical outcomes of volar plating for distal radius fractures. Review of the literature revealed that it was not necessary to fill all available distal locking screws, there was little evidence to support the use of 2 rows of screws distally over 1 row. Screws of 75% length of the distal cortex are sufficient to withstand standard postoperative regimes in extrarticular fractures. The was a paucity of evidence to conclude multidirectional locking plates were superior to fixed angle plates or that one brand of plate was superior to another.

Screw Length Optimization of a Volar Locking Plate Using Three Dimensional Preoperative Planning in Distal Radius Fractures

BACKGROUND

A three-dimensional (3D) digital pre-operative planning system for the osteosynthesis of distal radius fracture was developed. The objective of this study was to evaluate screw choices for three-dimensional (3D) digital pre-operative planning of osteosynthesis of distal radius fractures and to compare with the screw choices for the conventional method.

METHODS

Distal radius fracture patients who underwent osteosynthesis using volar locking plates were evaluated. Thirty wrists in the plan group utilized 3D preoperative planning, and nineteen wrists in the control group utilized conventional preoperative assessment. In the plan group, the 3D preoperative planning was performed prior to surgery. The reduction was simulated with 3D image, and the implant choice/placement also simulated on the 3D image. In the control group, standard preoperative planning was performed using posterior-anterior and lateral view radiographs, and CT scan. After the planning, osteosynthesis was performed. During the surgery, the operator performed the reduction and the placement of the plate while comparing images between the pre-operative plan and fluoroscopy. The distal screw lengths and the anteroposterior diameter of the radius along the axis of the distal screws were measured. The ratios of the screw length and radius diameter were evaluated. The screw/radius ratios within the range of 0.75-1.00 were considered appropriate. The screw choices less than 0.75, or greater than 1.00 were considered inappropriate. The rate of appropriate screw choices were compared between plan and control groups.

RESULTS

The results of appropriate screw choices were 86.1% and 74.8% in the plan group and the control group, respectively. The inappropriate screw choices were 14.0% and 25.2% in the plan group and the control group, respectively. The three-dimensional planning significantly increased appropriate screw choices compared to the conventional planning (p < 0.05).

CONCLUSIONS

Three-dimensional digital preoperative planning is useful for the optimization of screw lengths in osteosynthesis of distal radius fractures.

Distal radius fluoroscopic skyline view: extension-supination versus flexion-supination

The aim of our study was to compare the vertical fluoroscopic view of the wrist in extension and supination (ES) to the view in flexion and supination (FS) and determine which of the two views allowed the best visualization of four selected anatomical landmarks SDLR (radial styloid, dorsal radius cortex, Lister's tubercle and distal radioulnar joint). Our case series included 50 patients who had suffered a distal radius fracture and undergone an open reduction and internal fixation procedure with a volar locking plate. For each case, two fluoroscopic views were taken: ES (wrist extension and supination) (group I) and FS (wrist flexion and supination) (group II). Ten observers had to recognize the SDLR anatomical landmarks on 100 fluoroscopic skyline views (time 1) and 15 days later (time 2). The rate of recognition of the four anatomical landmarks was 78% in group I and 66% in group II (p < 0.001). The concordance rate of recognition of the four anatomical landmarks was mediocre (κ = 0.411). In conclusion, the vertical fluoroscopic skyline view in wrist extension and supination seems to be the most adequate view to assess the quality of the fracture reduction, the distal radioulnar joint and the length of the screws in open reduction and internal fixation of distal radius fractures with volar locking plates.

"Island-shape" Fractures of Lister's tubercle have an increased risk of delayed extensor pollicis longus rupture in distal radial fractures: After surgical treatment by volar locking plate

PURPOSE

Weperformed a retrospective case-control study to explore the hypothesis that conditions adjacent to Lister's tubercle (LT) in patients with distal radial fractures (DRFs) exhibiting dorsal comminution would influence the extent of the delayed extensor pollicis longus (EPL) rupture.

METHODS

Among patients treated by volar locking plates (VLPs) were placed between March 2011 and December 2015, 314 met inclusion/exclusion criteria and were analyzed. We designated group 1 as the "EPL rupture" and group 2 as the "no EPL rupture". Basic demographic data, radiological findings, and operative variables were evaluated. The fracture patterns around LT were classified as follows: type I, no fracture line/fragment in LT or the EPL groove (third compartment); type IIA, a fracture of LT or the EPL groove with displacement <2 mm; type IIB, a fracture of LT or the EPL groove with displacement >2 mm; and type III, the presence of an island-shaped fracture fragment of LT (isolated free fragment of LT).

RESULTS

EPL ruptures were found in 18 patients (5.7%). The basic demographic parameters did not differ significantly among the groups. Clinically, neither the time to surgery nor the type of VLP used (of three different types) was not significantly associated with EPL rupture, nor was arthroscopically assisted reduction. In terms of radiological variables, the overall ratio of intra-to-extra-articular fractures did not differ among the groups. However, the fracture type significantly affected the extent of the rupture (P < 0.001), the odds ratio of which increased significantly in the fracture order IIA, IIB, and III, compared to type I (91.9, 220.1, and 342.06, respectively).

CONCLUSIONS

The extent of delayed EPL rupture after treatment of DRFs by VLPs was associated with the fracture pattern around the LT. Especially, an island-shaped LT fracture was associated with a high rupture risk because callus formation narrowed the EPL groove.

LEVEL OF EVIDENCE

Therapeutic Level III.

Volar plating in distal radius fractures: A prospective clinical study on efficacy of dorsal tangential views to avoid screw penetration

PURPOSE

The purpose of this prospective cohort study of patients treated with volar plating for distal radius fractures is to evaluate the efficacy (defined as detection rate, or the ability to detect dorsally protruding screws) of additional dorsal tangential views (DTV) after obtaining standard anteroposterior (AP) and elevated lateral views by evaluating the change in intraoperative strategy in 100 patients.

MATERIALS AND METHODS

100 patients aged 18 years and older undergoing volar plating for acute extra- or intra- articular distal radius fractures were prospectively enrolled. Intraoperative fluoroscopy views, including AP, elevated lateral and DTV were obtained. Intraoperative -screw- revision frequency for dorsal screw protrusion, screw position relative to volar plate and to dorsal compartment, and screw lengths were evaluated.

RESULTS

Additional DTV led to a change of intraoperative management in 31 of 100 (31%) of patients. A total of 35 out of 504 screws (6.9%) were changed. Screws in the two most radial screws in the plate were at the highest risk of being revised; 16 (46%) screws in most radial position and nine (26%) screws in the 2nd from radial position were revised. Furthermore, five (14%) screws in both the 2nd from ulnar and most ulnar screw holes were revised after DTV. No screws were revised in the central hole. The median length of revised protruding screws was 22 mm (range, 12-26 mm), and these were changed to a mean length of 20  mm (range, 10-22 mm).

CONCLUSION

In this prospective series of 100 patients, obtaining additional DTV is found to be efficacious as it led to change in intraoperative strategy in one-third of patients. We concur with previous pilot studies that DTV, after obtaining conventional AP and elevated lateral views, is advised to avoid dorsally protruding screws, which could minimise the potential for iatrogenic extensor tendon rupture after volar plating for distal radius fractures. Diagnostic accuracy of DTV is subject of a subsequent prospective cohort study with post-operative CT to serve as the reference standard.

LEVEL OF EVIDENCE

.Prognostic I.

Volar Locking Plate Fixations for Displaced Distal Radius Fractures: An Evaluation of Complications and Radiographic Outcomes

BACKGROUND

A volar locking plate (VLP) is the most frequently used form of implant used for open reduction and internal fixation of distal radius fractures. They are known to have a complication rate of up to 27%. We hypothesized that plate design could influence complication rates.

METHODS

We performed a review of patients undergoing VLP fixation for distal radius fracture. A total of 228 patients underwent fixation with the Distal Volar Radial Anatomical (DVR) plate; 388 patients underwent fixation with the VariAx plate. Independent observers performed blinded case note and radiographic review, to assess for the quality of reduction, and complications for the inserted VLP.

RESULTS

Mean time to surgery was 6.0 days; mean follow-up was 17.5 weeks. Mean age was 56.5 years. The quality of reduction was classified as anatomical (46%), good (36.3%), moderate (13.0%), or poor (3.9%). Complications were identified in 109 patients (17%). Plate prominence was seen in 133 patients (21%). The DVR plate was less prominent ( P < .001) and had better overall radiographic appearances ( P = .025). Flexor tendon complications were related to plate prominence ( P = .005). Inferior reduction was associated with increased time to surgery ( P = .020).

CONCLUSIONS

This study highlights the importance of prompt surgery, effective fracture reduction, and careful plate positioning to avoid volar prominence.

Comparison of ultrasound and dorsal horizon radiographic view for the detection of dorsal screw penetration

OBJECTIVE

The aim of this study was to compare the efficiency of dorsal tangential fluoroscopy and ultrasonography in detecting dorsal screw penetration in distal radius volar locking plate applications.

METHODS

Ten cadaveric forearms were operated. The distal four screws were protruded 0, 1 and 2 mm into each of the second, third and fourth dorsal compartments of distal radius. Dorsal horizon views were taken using fluoroscopy. Each radiographic image was evaluated by two orthopedic surgeons who are blinded to procedure. Sonographic evaluations were performed by an orthopedic surgeon blinded to the procedure. Both dorsal horizon view and ultrasonography assessments were noted by the evaluators whether the tip of the screw penetrated or not the dorsal cortex for each compartment.

RESULTS

No significant difference was observed on correct detection of 0 mm, 1 mm and 2 mm screw penetrations at second and third compartments. In the fourth compartment, there was no difference with 0 mm and 2 mm penetrations but correct detection accuracy of 1 mm screw penetration was 87% in ultrasonography group and 71% in dorsal horizon view group.

CONCLUSIONS

The accuracy of ultrasonography on 1 mm penetration at the fourth compartment is better than dorsal horizon view. However, dorsal horizon view and ultrasonography accuracy is similar for the other compartments and penetration levels. Ultrasonography is a reliable and effective procedure for detection of dorsal screw penetrations.

LEVEL OF EVIDENCE

Level III, Diagnostic study.

Sensitivity and Specificity of Skyline and Carpal Shoot-Through Fluoroscopic Views of Volar Plate Fixation of the Distal Radius: A Cadaveric Investigation of Dorsal Cortex Screw Penetration

BACKGROUND

Volar plate fixation of distal radius fractures can result in soft tissue injuries. Abnormal contour of the dorsal cortex of the distal radius provides difficulties in discerning screw penetration on standard radiographs. The skyline and carpal shoot-through views are additional views to improve dorsal cortex visibility. We report on the sensitivity and specificity of determining screw protrusion with these views.

METHODS

Seven fresh frozen cadavers were instrumented with a distal radius volar locking plate. Initial screw length was determined by depth gauge measurement. A dorsal dissection of the wrist was performed to detect screw penetration. Protruding screws were documented and replaced with screws of the appropriate length and deemed as baseline. Screws were then sequentially lengthened by 2 and 4 mm. Skyline and carpal shoot-through views were obtained at baseline, 2 mm, and 4 mm. The images were randomized and compiled into an untimed survey asking orthopedic surgeons to determine whether screws were penetrating through the dorsal cortex.

RESULTS

Based on depth gauge measurements, 4 out of 44 (9.1%) volar plate locking screws penetrated the dorsal cortex, as confirmed with dorsal dissection. Sensitivities for the skyline and carpal shoot-through views were 75% and 86% ( P ≤ .001), respectively, for 2-mm protrusions, and 76% and 89% ( P ≤ .001), respectively, for 4-mm screw protrusions. Specificities were 85% and 84% for the skyline and shoot-through views, respectively.

CONCLUSIONS

We believe that the carpal shoot-through view has utility and can be implemented to augment standard intraoperative views, and may decrease the incidence of screw protrusion resulting in soft tissue injuries.

Detections of Screw Penetration during Volar Plating for Distal Radius Fractures

Background  We evaluated the detection for screw penetration on the dorsal cortex of the radius in serial oblique, dorsal tangential, and radial groove radiographic views in volar plating fixation. Materials and Methods  Eight screw positions were set in each of the four cadaveric radii. Screw 1 was placed in the styloid subregion, whereas screws 2 and 3 were placed just proximal to the styloid and were defined for the radial region of the radius. Screws 4 (distal to the extensor pollicis longus [EPL] groove), 5 (the distal half of the groove), and 6 (the proximal half of the groove) were placed in the central region of the radius. Screws 7 (just medial to the groove) and 8 (sigmoid notch subregion) were positioned in the ulnar region of the radius. The screws were overlengthened by 1 and 2 mm and were evaluated in three radiographic views. Results  Penetrations in the radial region were fully visible in supinated oblique views with 1- and 2-mm overlengthened screws. The penetration of screw 4 was clearly observable over a considerable range of views. However, the 1-mm penetration of screw 5 was not detectable at any angle of projection. Detection of the ulnar region screw was the most difficult among the three regions with oblique views. In the dorsal tangential view, the 1-mm penetration of screw 4 was not observed in any of the four radii, but the penetration of screw 5 was detectable in all the radii. The screws 2, 3, 5, 7, and 8 were readily detectable. The screw 4 was barely seen in the radial groove view, while the screws 5 and 6 were readily detectable. Conclusion/Clinical Relevance  Appropriate combinations of these well-known radiological views are essential for the overall detection of penetrated screws during plating in distal radius fractures.

Comparison of lateral and skyline fluoroscopic views for detection of prominent screws in distal radius fractures plating: results of an ultrasonographic study

INTRODUCTION

Extensor tendon rupture is a recognized complication of volar plate fixation of distal radius fractures due to screws protruding past the dorsal cortex. The aim of this study was to compare the Skyline view with traditional lateral fluoroscopic views using ultrasonography as a reference standard in the postoperative assessment.

MATERIALS AND METHODS

A monocentric prospective study was conducted to identify screws penetrating the dorsal cortex after volar plating of distal radius fractures.

PATIENTS AND INTERVENTION

Intraoperative anteroposterior (AP) and lateral views were used for group A (28 patients). AP, lateral and skyline fluoroscopic views were used for Group B (40 patients). Prominent screws were changed.

MAIN OUTCOME MEASUREMENTS

Ultrasound was done 6 months postoperatively to evaluate the number and length of prominent dorsal screws and any signs of extensor tenosynovitis.

RESULTS

The number of prominent dorsal screws exceeding 1 mm was 14 in group A (14.9%), and 16 screws (11.8%) in group B (p = 0.487). Average length of prominent dorsal screw was 1.9 mm (range 1-2.1 mm) for group A and 2.4 mm (range 1.1-4.8 mm) for group B (p = 0.534). The number of patients with extensor tenosynovitis was 11 for group A and 12 for group B (p = 0.66).

CONCLUSIONS

The Skyline view does not provide sensitive and reliable detection of the dorsal screw penetration. Intraoperative ultrasound might be a better tool to detect screw prominence.

LEVEL OF EVIDENCE

III, case-control study.

Detection of penetration of the dorsal cortex by epiphyseal screws of distal radius volar plates: Anatomical study comparing ultrasound and fluoroscopy

HYPOTHESIS

Osteosynthesis of the distal radius by a volar plate can be complicated by lesions of extensor tendons by screws penetrating the dorsal cortex. The fluoroscopic skyline view enables to confirm the length of the screws. To avoid its risk of irradiation, some authors have recommended using ultrasound instead.

MATERIAL AND METHODS

The goal of this study was to demonstrate that the detection rate of screws penetrating the dorsal cortex was at least as good using ultrasound compared to fluoroscopic skyline. A volar plate in which one screw penetrated the dorsal cortex was implanted in 10 cadaveric wrists. Three observers had to detect which screw penetrated the dorsal cortex using ultrasound and then a fluoroscopic skyline.

RESULTS

The detection rate of screws penetrating the dorsal cortex was 43.33% with ultrasound and 96.97% using the fluoroscopic skyline. Agreement between the observers was poor with ultrasound and good with fluoroscopy.

CONCLUSION

Our results show that ultrasound cannot replace the fluoroscopic skyline view to detect screws penetrating the dorsal cortex of the distal radius in clinical practice.

LEVEL OF EVIDENCE

II.

[Distal radius fracture of the adult : Diagnostics and therapy]

Fractures of the distal radius are very common. The majority of patients are elderly females. High impact trauma are often responsible for fractures in young men. Clinical and radiological diagnostics, including computer-assisted tomography (CAT) scan, are generally sufficient. The indication for conservative treatment is still recommended for specific fracture patterns. Application of palmar locking plates after open reduction proved to be efficacious for the majority of fracture patterns. Furthermore, precise detection and treatment of concomitant lesions are mandatory in order to prevent complications.

[Secondary tendon reconstruction on the thumb]

Closed tendon ruptures of the thumb that require secondary reconstruction can affect the extensor pollicis longus (EPL), extensor pollicis brevis (EPB) and flexor pollicis longus (FPL) tendons. Treatment of rupture of the EPB tendon consists of refixation to the bone and temporary transfixation of the joint. In the case of preexisting or posttraumatic arthrosis, definitive arthrodesis of the thumb is the best procedure. Closed ruptures of the EPL and FPL tendons at the wrist joint cannot be treated by direct tendon suture. Rupture of the EPL tendon occurs after distal radius fractures either due to protruding screws or following conservative treatment especially in undisplaced fractures. Transfer of the extensor indicis tendon to the distal EPL stump is a good option and free interposition of the palmaris longus tendon is a possible alternative. The tension should be adjusted to slight overcorrection, which can be checked intraoperatively by performing the tenodesis test. Closed FPL ruptures at the wrist typically occur 3-6 months after osteosynthesis of distal radius fractures with palmar plates and are mostly characterized by crepitation and pain lasting for several weeks. They can be prevented by premature plate removal, synovectomy and carpal tunnel release. For treatment of a ruptured FPL tendon in adult patients the options for tendon reconstruction should be weighed up against the less complicated tenodesis or arthrodesis of the thumb interphalangeal joint.

[Complications of volar locking plates used to treat distal radius fractures]

About 10 years after volar locking plates were introduced to treat acute distal radius fractures, several papers have reported short-term complications. The aim of this paper was to report our complication rate over a 2-year period and to compare it to the literature. We found similar complication rates despite different classification systems. Because of the prospective nature of our study, we were able to demonstrate that extra-articular and/or intra-articular scores exceeding 8 points on a 12-points scale were statistically associated with more complications, irrespective of the patient's overall health and age.

Detecting dorsal screw penetration following volar plate fixation of the distal radius – A validation study in a saw bone model

Background

The fluoroscopic detection of dorsal screw protrusion following volar locking plate fixation of distal radius fractures remains difficult. The carpal shoot through view has recently been reported to result in a 17% intra-operative screw exchange rate. The aim of the current study was to assess the sensitivity of the carpal shoot through view in comparison to conventional fluoroscopic views for detecting dorsal cortical and distal radio-ulnar joint screw penetration.

Methods

A volar locking plate was applied to a saw bone model and fluoroscopic views taken with the distal screws inserted flush or protruding by two full screw threads. Images were then shown to 10 orthopaedic surgeons who were asked to identify excessively long screws.

Results

The CST view demonstrated the greatest sensitivity for detection of dorsal screw penetration (78%). Its inter-observer reliability was 0.66 (substantial agreement) and intra-observer reliability 0.86 (near perfect agreement). The dorsal skyline had a sensitivity of 51%; the elevated lateral view had a sensitivity of only 16%.

Conclusions

The current study confirms that the elevated lateral view cannot be relied upon alone for the detection of dorsal screw penetration. The CST view is a valid technique demonstrating the greatest sensitivity in comparison to established intra-operative views.

Using self-drilling screws in volar plate osteosynthesis for distal radius fractures: a feasibility study

Background

Symptomatic extensor tendon irritation is a frequent complication in volar plate osteosynthesis of distal radius fractures. It is typically caused by dorsal screw protrusion and overdrilling of the dorsal cortex. The use of self-drilling locking screws (SDLS) could overcome both causes. The practical applicability of SDLS depends on two prerequisites: (1) the feasibility of preoperative distal screw length determination, and (2) sufficient primary biomechanical stability of SDLS compared to standard locking screws (SLS).

Methods

We first assessed the feasibility of preoperative screw length determination (1): Distal radius width, depth and distal screw lengths were measured in 38 human radii. Correlations between distal radius width and depth were assessed, a cluster analysis (Ward’s method and squared Euclidean distance) for distal radius width conducted, and intra-cluster screw lengths analyzed (ANOVA). The biomechanical performance of SDLS (2) was assessed by comparison to SLS in a distal radius fracture model (AO-23 A3). 75 % distal screw length was chosen for both groups to simulate a worst-case scenario. Uniaxial compression tests were conducted to measure stiffness, elastic limit, maximum force and residual tilt. Statistics comprised of independent sample t-tests and a Bonferroni correction (p < 0.0125).

Results

(1) Distal radius width and depth showed a high correlation (R² = 0.79; p < 0.001). Three distal radius width clusters could be identified: small <34 mm; medium 34–36.9 mm; large >36.9 mm. ANOVA and Tukey post-hoc analysis revealed significantly different volar-dorsal depths (p < 0.05) for nearly all screws. (2) To assess biomechanical stability nine specimens were tested each; no significant differences were found between the SDLS and SLS groups.

Conclusions

This feasibility study demonstrates that (1) distal radius width can be used as a predictor for distal screw length and (2) that SDLS provides mechanical stability equivalent to SLS. These results highlight the feasibility of applying SDLS screws in volar plate osteosynthesis at least in extraarticular fractures.

Predicting a safe screw length for volar plate fixation of distal radius fractures: lunate depth as a marker for distal radius depth

PURPOSE

We hypothesized that the lunate depth as measured on plain lateral radiographs can be used to predict distal radius depth radially and ulnarly and serve as a useful reference for intraoperative screw placement in volar plate fixation of distal radius fractures.

METHODS

Plain radiographs and magnetic resonance imaging (MRI) of the wrists of 30 patients were reviewed. The lunate depth and the maximal depth of the distal radius were determined from plain lateral radiographs. Depth of the distal radius, measured in quartiles, was determined from axial MRI images, and the lunate depth was obtained from sagittal MRI images. The depth of the distal radius in each quartile was then calculated related to the lunate depth.

RESULTS

The mean depth of the lunate on plain radiographs and MRI was 17.5 mm and 17.4 mm, respectively. The depth of the distal radius from ulnar to radial was 18.4 mm, 20.2 mm, 19.4 mm, and 15.1 mm for the 1st through 4th quartiles, respectively. The depth of the distal radius is the least radially (4th quartile), with a mean 87% of the lunate depth, and greatest in the 2nd quartile, with a mean 116% of the lunate depth.

CONCLUSIONS

The depth of the lunate as measured on plain radiographs can be used as a marker for drilling and placement of safe screw lengths during volar plate fixation of distal radius fractures. We recommend that surgeons use the lunate depth as an estimate for the length of their longest screw when fixing distal radius fractures with volar plate techniques to avoid extensor tendon irritation and rupture.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

Volar locking plate fixation of distal radius fractures: use of an intra-operative 'carpal shoot through' view to identify dorsal compartment and distal radioulnar joint screw penetration

INTRODUCTION

We report our experience using a 'carpal shoot through' view of the distal radius to identify dorsal compartment screw penetration intra-operatively when performing volar plating of the distal radius.

METHODS

A prospective study of 42 patients (mean age 56 years) with acute distal radius fractures treated with open reduction internal fixation was undertaken. Surgical fixation was performed using a volar locking plate in all patients. After plate application, inclined posteroanterior and lateral radiographs were taken followed by the carpal shoot through view.

RESULTS

In six cases (14 %), the carpal shoot through view revealed dorsal screw protrusion, which was not detectable on standard PA and lateral views. In one case, a screw had penetrated the distal radioulnar joint (DRUJ), which was only apparent on the shoot through view. The overall screw exchange rate was 17 %.

CONCLUSIONS

Using the hand and carpus to minimise the contrast in X-ray penetration, the dorsal cortex of the distal radius may be imaged intra-operatively and dorsal compartment screw penetration detected in cases with significant multifragmentation when screw measurement is difficult. This view potentially reduces the risk of post-operative pain and extensor tendon injury and also provides excellent visualisation of the DRUJ.

The utility of the fluoroscopic skyline view during volar locking plate fixation of distal radius fractures

Background Open reduction and internal fixation (ORIF) using a volar locking plate is a common method for treating displaced distal radius fractures. There is, however, the risk of extensor tendon rupture due to protrusion of the screw tips past the dorsal cortex, which cannot always be adequately seen on a lateral fluoroscopic view. We therefore wished to compare the sensitivity of an intraoperative fluoroscopic skyline view to a lateral fluorosocopic view in detecting past pointing of these screws. Material and Methods Our series included 75 patients with an average age of 59 years who underwent volar locked plate fixation of a displaced distal radius fracture. Intraoperative anteroposterior (AP), lateral, and skyline fluoroscopic views were performed in each case. The number of screws that were seen to protrude past the dorsal cortex of the distal fracture fragment were recorded for both the lateral and skyline views. The number of screws that required exchange was also documented. Results No screws were seen to protrude past the dorsal cortical bone on the lateral fluroscopic views. 15 of 300 screws (5%) were seen to protrude past the dorsal cortex by an average of 0.8 mm (range, 0.5 to 2 mm) and were exchanged for shorter screws in 11/75 patients. Conclusion Our results demonstrate that the skyline is more sensitive than a lateral fluoroscopic view at demonstrating protrusion of the screws in the distal fracture fragment following volar locked plate fixation. Level of Evidence IV.

How many radiographs are needed to detect angular stable head screw cut outs of the proximal humerus - a cadaver study

INTRODUCTION

Cut out of locking head screws is the most common complication of locking plates in fracture fixation of the proximal humerus with potentially disastrous consequences. Aim of the study was to find the single best and combination of radiographic projections to reliably detect screw cut outs.

MATERIALS AND METHODS

The locking plate was fixed to six cadaveric proximal humeri. Six different radiographs were performed: anteriorposterior in internal (apIR), in neutral (ap0) and in 30° external rotation (apER); axial in 30° (ax30) and 60° (ax60) abduction and an outlet view. Each head screw (n=9) was sequentially exchanged to perforate the humeral head with the tip and all radiographs were repeated for each cut out. Randomized image reading by two blinded examiners for cut out was done for single projection and combinations.

RESULTS

Interrater agreement was 0.72-0.93. Best single projection was ax30 (sensitivity 76%) and the worst was the outlet view (sens. 17%). Standard combination of apIR/outlet reached a sens. of 54%. The best combination of two was: apER/ax30 (90% sens.), of three: apIR/apER/ax30 (96% sens.) and of four: apIR/ap0/apER/ax30 (100% sens.).

CONCLUSION

Standard radiographs (ap/outlet), especially in internal rotation, may miss nearly half of screw cut outs. Single best radiographic projection was an axial view with 30° abduction. To account for all cut outs and correct screw position a combination of four projections was needed. These simple and feasible intraoperative and postoperative radiographs help to detect screw perforations of the locking plate reliably.

LEVEL OF EVIDENCE

I (Study of Diagnostic Test).

A comparative study about ionizing radiation emitted during radiological "skyline" view of the wrist in pronation versus supination

The dorsal tangential view to the distal radius or "skyline," used to control the length of the screws for the ORIF with volar plates, is carried out in supination (fluoroscope vertical) or in pronation (fluoroscope horizontal). The purpose of this study was to compare the dose of ionizing radiation emitted during a "skyline" view in supination versus pronation. A "skyline" was performed on 14 fresh cadaveric wrists. In group 1, the fluoroscope was positioned vertically and the wrist was held in supination. In group 2, the fluoroscope was positioned horizontally and the wrist held in pronation. The average dose of ionizing radiation was 0.9286 cGy/cm(2) (group 1) and 0.8751 cGy/cm(2) (group 2). The difference was not statistically significant. Overall, the emitted dose for the "skyline" is negligible compared to that of a standard wrist radiography with no difference between the vertical and horizontal positioning. Peroperatively, the vertical "skyline" seems easier to setup, less time consuming and less prone to asepsis faults.

Use of the radial groove view intra-operatively to prevent damage to the extensor pollicis longus tendon by protruding screws during volar plating of a distal radial fracture

The aims of this study were to assess the efficacy of a newly designed radiological technique (the radial groove view) for the detection of protrusion of screws in the groove for the extensor pollicis longus tendon (EPL) during plating of distal radial fractures. We also aimed to determine the optimum position of the forearm to obtain this view. We initially analysed the anatomy of the EPL groove by performing three-dimensional CT on 51 normal forearms. The mean horizontal angle of the groove was 17.8° (14° to 23°). We found that the ideal position of the fluoroscopic beam to obtain this view was 20° in the horizontal plane and 5° in the sagittal plane. We then intra-operatively assessed the use of the radial groove view for detecting protrusion of screws in the EPL groove in 93 fractures that were treated by volar plating. A total of 13 protruding screws were detected. They were changed to shorter screws and these patients underwent CT scans of the wrist immediately post-operatively. There remained one screw that was protruding. These findings suggest that the use of the radial groove view intra-operatively is a good method of assessing the possible protrusion of screws into the groove of EPL when plating a fracture of the distal radius.

Intraoperative C-arm CT imaging in angular stable plate osteosynthesis of distal radius fractures

The purpose of this study was to analyze the practicability and benefit of intraoperative C-arm computed tomography (CT) imaging in volar plate osteosynthesis of unstable distal radius fractures. During a 1 year period, intraoperative three dimensional (3D) imaging with the ARCADIS Orbic 3D was performed in addition to standard fluoroscopy in 51 cases. The volar angular stable plate oesteosyntheses were analyzed intraoperatively and, if necessary, improved immediately. The duration of the scan and radiation exposure dose were measured. On average, performance of the scan and analysis of the CT dataset took 6.7 minutes. In 31.3% of the surgeries a misplacement of screws was detected and correction was done immediately. C-arm CT imaging can easily be integrated in the normal course of surgery. As a complement to the standard 2D-fluoroscopy, the C-arm CT is a useful tool to evaluate the quality of osteosynthesis.

Complications of distal radius locking plates

Fixation of distal radius fractures via locking plates is an increasingly popular method. However, these plates include variety of complications, such as flexor and extensor tenosynovitis, tendon injury and intra articular screw or peg penetration. Although they offer superior stability and early mobility, if used improperly; they may cause serious complications related to the implant. Proper use of the implant with strict adherence to the fixation principles and close follow up of patients are very important in order to decrease the rate and severity of complications.

Distal radius fractures: current concepts

Despite the frequency of distal radius fractures, the optimal treatment remains without consensus opinion. A trend toward increased distal radius fracture open reduction and internal fixation has been identified, with biomechanical and clinical studies suggesting treatment advantages of certain fixation methods over others. Well-controlled patient trials are still missing to lend objective findings to management algorithms. This article reviews the literature over the past 5 years to guide our management regarding this common upper-extremity injury.