distal radius fractures ( drf ) is one of the most common cause of emergency department visits , comprising approximately one - sixth of fracture cases ( 1 , 2 ) . except for trauma , pathological fractures due to osteoporosis , especially in elderly patients , is also one of the causes for this type of fracture ( 3 , 4 ) . depending on the type of fracture , management is different , but generally it needs closed reduction , casting and future follow - up ( 5 ) . restoration of normal or nearly normal anatomic alignment is acknowledged as a key component of the treatment of drf .   at present , conditions such as inflammation of surrounding soft tissues prevent the physician from gaining adequate information about the reduction procedure carried out , which in turn can lead to requesting repeated radiographs . it can increase the need for sedation , unnecessary exposure to x - rays , and infliction of higher expenses ( 7 ) . recently , the use of ultrasonography ( us ) instead of plain radiography has been under consideration as a practical monitoring tool of closed reductions in extra - articular drf ( 1 , 2 , 6 ) . accordingly , the present study was aimed to evaluate the accuracy of bedside us for determining the adequacy of drf reduction compared with standard plain radiography . study design and setting 
  this cross sectional study has been performed from september 2011 to september 2012 in the emergency department of al - zahra hospital , isfahan , iran . the study protocol was approved by isfahan university of medical sciences institutional review board and registered in www.clinicaltrial.gov by registration code : nct01823692 . based on the study protocol , us and radiographic findings were compared in the same group of patients . anterior - posterior view : ( a ) before reduction ; ( b ) after reduction lateral view : ( a ) before reduction ; ( b ) after reduction conventional radiographic parameters . from left to right : radial inclination ; radial height ; volar tilt patients undergoing sono - guided manipulation and reduction were enrolled over a twelve - month period , representing a convenience sample . eligible patients were prospectively recruited based on the inclusion criteria as age>18 and diagnosis of drf based on plain radiography . in addition , the exclusion criteria consisted of the following : open fractures , fractures with more than 20 angulation , intra - articular involvement , comminuted fractures with neurovascular compromise , patients requiring surgery due to other causes , need to intensive care , and patients refusal to participate in the study . patients baseline characteristics accuracy of ultrasonography in confirmation of adequate reduction compare to radiography ci : confidence interval after registration of demographic data , the patients underwent manipulation and reduction by one emergency medicine specialist under bier block regional anesthesia or procedural sedation - analgesia . this physician passed a comprehensive training course regarding to sono - guided reduction , and determining the sufficiency of reduction based on us findings . us was performed in a long axis in both anterior - posterior and lateral views ( figures 1 and 2 ) . when the distal and proximal cortices aligned into a straight line ( less than 3 mm difference ) , the reduction was defined as successful . follow - up plain radiographs were also obtained in the anterior - posterior and lateral views ( gold standard ) and reviewed by one blinded radiologist . if plain radiographs had the following criteria , the reduction was considered successful : 1 ) normal radial inclination of 15 - 25 ; 2 ) radial height at least 5 mm or higher ; 3 ) volar / palmar tilt -10 to + 20 ( 8) ( figure 3 ) . finally , proper fixation was applied . distal radius was defined as a distance less than 3 cm from the radio - carpal joint ( 9 ) . statistical analysis 
  following a descriptive analysis , the sensitivity , specificity , and positive and negative predicative values were calculated . in addition , cohen s kappa coefficient was used to evaluate inter - rater reliability between us and radiographic findings . kappa index values < 0.2 , 0.21 - 0.4 , 0.41 - 0.6 , 0.61 - 0.8 and > 0.8 were considered weak , rather weak , moderate , good , and excellent , respectively . of the 180 patients initially enrolled in the study , 26 were excluded in the final analysis ( 10 with open fractures , six angulation>20 , five intra - articular involvement and five neurovascular compromise ) . finally , 154 patients participated in this study ( 53.9% female ; 55.2% right hand drf ) with mean age of 40.0314.7 ( range : 22 - 73 ) . table 1 present the baseline characteristics of these patients . based on us and radiographic findings successful reduction was confirmed in 145 ( 94.2% ) and 146 ( 94.8% ) cases , respectively . us had sensitivity , specificity , positive and negative predictive value of 99.3% , 100.0%100.0% , and 88.9% in confirmation of successful reduction , respectively ( table 2 ) . in addition , inter - rater agreement of reduction success between the two assessment methods was 99.35% . in addition , inter - rater reliability based on cohen s kappa coefficient was 0.94 ( 95% ci : 0.89 - 0.99 ; p<0.0001 ) . the results of the present study showed a high rate of similarity between us and radiographic findings in confirmation of adequate reduction . it seems that a sensitivity of 99.3% and a specificity of 100% make us a reliable tool for evaluation of successful reduction . sono - guided reduction is an accurate , simple , and safe technique that provides the considerable advantage of real - time observation . in addition us should decrease the number of reduction attempts and consequently fewer traumas to the surrounding soft tissues ( 8) . previous studies have been reported the sensitivity and specificity of us in confirming the adequacy of reduction between 94%-96% and 56%-97% , respectively ( 2 , 10 ) . considering the limitation of us in observation of the articular surface , because of their deep - seated position and blocked by carpal component , we excluded all patients with intra - articular fractures . multiple studies have been declared the successful utility of sono - guided reduction for different type of fractures . ang et al . stated that us guidance is effective and recommended it for routine use in the reduction of drf ( 8) . eckert et al confirm that ultrasound is an applicable and safe alternative tool to x - rays in non - displaced forearm fractures ( 10 ) . chern et al . depicted that all parameters measured on the us and radiographic findings showed remarkable restoration of anatomic alignment after reduction , and all indicators were the same on the two types of images ( 11 ) . some inherent characteristics of us such as : inability to bone penetration , observation of articular surface , and measurement of conventional radiographic parameters ) ; unlike successful rate in different age ( 12 , 13 ) ; quality and quantity of the training courses ; and operator dependency ; are among limitations in the widespread use of us for guidance and confirmation of closed fracture reduction in ed . therefore , our result may not be applicable to other age groups , or other fracture sites . in addition , although we standardized the initial training for the physicians , our study size was too small to make meaningful subgroup analysis based on level of training or prior us experience . finally , while us has some limitations that prevent it from completely replacing conventional radiography , it can facilitate the reduction and prevent repeated reduction attempts . it seems that us could be considered as a highly sensitive , accurate , easy to use , noninvasive and safe tool for guidance and confirming of closed reduction in drf . this study was supported financially by isfahan university of medical sciences , isfahan , iran . all authors met all four recommended criteria of international committee of medical journal editors for authorship contribution .
introduction : restoration of normal anatomic alignment is a key component of the treatment of distal radius fractures ( drf ) . 
 this study aimed to evaluate the accuracy of ultrasonography ( us ) in determining the adequacy of closed reduction in these fractures . 
 methods : drf patients admitted to the emergency department of al - zahra hospital , isfahan , iran from september 2011 to 2012 , were enrolled . 
 after closed reduction , the adequacy was investigated through both us and control plain radiography . 
 then , sensitivity , specificity , positive and negative predicative values of us in confirmation of closed reduction was evaluated . 
 in addition , inter - rater agreement between the two diagnostic tools was analyzed by calculating cohen s kappa coefficient . 
 results : finally , 154 patients were evaluated ( females : 53.9% ) with mean age of 40.0314.7 ( range : 22 - 73 ) . 
 us had sensitivity , specificity , positive and negative predictive value of 99.3% ( 95%ci : 96.2 - 99.9 ) , 100.0% ( 95%ci : 62.9 - 100.0 ) , 100.0% ( 95%ci : 97.5 - 100.0 ) , and 88.9% ( 95%ci : 51.7 - 98.1 ) in confirmation of the adequate reduction , respectively . 
 in addition , inter - rater reliability was 0.94 ( 95%ci : 0.89 - 0.99 ; p<0.0001 ) . 
 conclusion : it seems that us could be considered as a highly sensitive , accurate , easy to use , noninvasive and safe tool for guidance and confirmation of closed reduction in drf .