Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 
  • Users Online: 1180
  • Home
  • Print this page
  • Email this page

 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 14  |  Issue : 2  |  Page : 69-75

Patterns of distal humeral fractures among Nigerians: A radiologic study


Department of Anatomy, School of Basic Medical Sciences, College of Medical Sciences, University of Benin, Benin City, Edo State, Nigeria

Date of Web Publication19-Feb-2016

Correspondence Address:
Vitalis Chukwuma Ezeuko
Department of Anatomy, School of Basic Medical Sciences, College of Medical Sciences, University of Benin, Benin City, Edo State
Nigeria
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1596-2393.177028

Rights and Permissions
  Abstract 

Background: Fractures of the distal humerus constitute between 0.5% and 2% of all fractures, and about one-third of fractures around the elbow joint. This study was aimed at classifying the patterns of distal humeral fractures among Nigerians. Materials and Methods: The study was carried out retrospectively at the Department of Medical Records, National Orthopedic Hospital, Igbobi, Lagos State, Nigeria. Plain films of X-ray (both anteroposterior and lateral views) that were taken between 2007 and 2012. The films were from a total number of 144 patients of ages ranging from birth to 100 years (0–100 years), comprising of 88 males and 56 females. Distal humeral fractures were classified according to Müller's classification for the Association for the Study of Internal Fixation. Comparisons of the patterns of distal humeral fractures were made between the sexes, sides affected, age groups, and causes of the fractures. Results: The results showed that the most frequent type of distal humeral fractures was extra-articular fractures (50.7% [73/144]) followed by partial articular fractures (31.9% [46/144]), while the least frequent was complete articular fractures (17.4% [25/144]). Conclusion: This study shows to a great extent that there is a pattern for distal humeral fractures among Nigerians. This type of epidemiologic studies offers important data that contributes to improvement in fracture management and treatment.

Keywords: Distal, fractures, humerus, Nigerians, pattern


How to cite this article:
Ezeuko VC, Ehimigbai AR, Esechie EL. Patterns of distal humeral fractures among Nigerians: A radiologic study. J Exp Clin Anat 2015;14:69-75

How to cite this URL:
Ezeuko VC, Ehimigbai AR, Esechie EL. Patterns of distal humeral fractures among Nigerians: A radiologic study. J Exp Clin Anat [serial online] 2015 [cited 2019 Nov 20];14:69-75. Available from: http://www.jecajournal.org/text.asp?2015/14/2/69/177028




  Introduction Top


Fractures of the distal humerus constitute between 0.5% and 2% of all fractures, and about one-third of fractures around the elbow joint (Webb, 2001). More so, supracondylar fractures of the distal humerus are quite high in children, accounting for about 17.9% of all pediatric fractures. This makes them the second most common pediatric fracture (Cheng et al., 1999), second only to distal radial fractures.

Past studies had revealed that distal humeral fractures are more common in children. These injuries are most commonly caused by falls, and occur more frequently in the non-dominant arm (Cheng et al., 1999; Cheng et al., 2001; Ezeuko et al., 2014a).

Several authors had proposed different classification systems for distal humeral fractures (Reich, 1936; Riseborough and Radin, 1969; Jupiter and Mehne, 1992; Ring et al., 2003). However, for research purposes, the most widely accepted classification system is that of Müller et al. (1990) and Orthopaedic Trauma Association (OTA) (1996). Using alpha-numeric system, Müller et al., (1990) assigned distal humeral fractures into three main types: Type A (extra-articular), Type B (partial articular), and Type C (complete articular). The OTA extended this classification further into sub-types for further fracture details. Although the Muller/OTA system's clinical application is limited and is hindered by poor inter-observer reliability beyond identification of the basic three types (Wainwright et al., 2000), it has remained useful for cataloging fractures for research purposes.

There is no literature available on the pattern of fractures of the distal humeral among Nigerians. Hence, this study was aimed at classifying the pattern of distal humeral fractures among Nigerian using the Müller's classification system.


  Materials and Methods Top


The study was carried out retrospectively at the Department of Medical Records, National Orthopedic Hospital, Igbobi, Lagos State, Nigeria. Plain films of X-ray (both anteroposterior and lateral views) that were taken between 2007 and 2012. The films were from a total number of 144 patients of ages ranging from birth to 100 years (0–100 years), comprised of 88 males and 56 females.

The plain films that were selected for the study were strictly those of Nigerians based on the information given by the subjects and filled in their case notes.

Information that were gathered from the patients' case notes included age of the patients, gender of the patients, side affected, and cause of the fracture. The causes were grouped into three: Those that occurred as a result of the fall, those occurred as a result of road traffic accident (RTA) and those that occurred as a result of other causes (these included birth injuries, pathological, industrial machines, and cutlass). The subjects were socio-economically grouped according to their ages into: Children (17 years and below), young (18–39 years), middle age (40–64 years), and elderly (65 years and above).

Distal humeral fractures were classified according to Müller et al. (1990) into three main types with three groups in each type as shown in [Figure 1].
Figure 1: Müller's classification of distal humeral fractures (Müller et al., 1990)

Click here to view


The results were presented in tables showing percentage frequencies and fractional frequencies. Comparisons of the patterns of distal humeral fractures were made between the sexes, sides affected, age groups, and causes of the fractures.


  Results Top


[Table 1] presents the fracture pattern among the subjects studied. The most frequent type of distal humeral fractures were extra-articular fractures (50.7% [73/144]) followed by partial articular fractures (31.9% [46/144]) while the least frequent was the complete articular fractures (17.4% [25/144]).
Table 1: Fracture pattern among the subjects studied

Click here to view


Among the extra-articular fracture cases [Table 1], apophyseal avulsion fractures were the most frequent (47.9% [35/73]) followed by the metaphyseal simple fractures (31.5% [23/73]) while the metaphyseal multifragmentary fractures were the least frequent (20.5% [15/73]).

Among the partial articular fracture cases [Table 1], sagittal lateral condyle fractures were the most frequent (65.2% [30/46]) followed by the sagittal medial condyle fractures (30.4% [14/46]) while the frontal fractures were the least frequent (4.3% [2/46]).

Among the complete articular fracture cases [Table 1], articular simple-metaphyseal simple fractures were the most frequent (84.0% [21/25]). The frequency of articular simple, metaphyseal multifragmentary and articular multifragmentary group were equal (8.0% [2/25] each).

[Table 2] presents comparison of the pattern of distal humeral fractures between males and females. It showed that there is a similar pattern of distal humeral fractures in both sexes with slight variation in the complete articular fractures. The most frequent type of distal humeral fractures was extra-articular fractures (50.0% [44/88] in males and 51.8% [29/56] in females) followed by partial articular fractures (31.8% [28/88] in males and 32.1% [18/56] in females) while the least frequent type was the complete articular fractures (18.2% [16/88] in males and 16.1% [9/56] in females).
Table 2: Comparison of the pattern of distal humeral fractures between males and females

Click here to view


Among the extra-articular fracture cases [Table 2], apophyseal avulsion fractures were the most frequent (43.2% [19/44] in males and 55.2% [16/29] in females), followed by the metaphyseal simple fractures (36.4% [16/44] in males and 24.1% [7/29] in females) while the metaphyseal multifragmentary fractures were the least frequent (20.5% [9/44] in males and 20.7% [6/29] in females).

Among the partial articular fracture cases [Table 2], sagittal lateral condyle fractures were the most frequent (67.9% [19/28] in males and 61.1% [11/18] in females), followed by the sagittal medial condyle fractures (28.6% [8/28] in males and 33.3% [6/18] in females) while the frontal fractures were the least frequent (3.6% [1/28] in males and 5.6% [1/18] in females).

Among the complete articular fracture cases [Table 2], articular simple-metaphyseal simple fractures were the most frequent (81.3% [13/16] in males and 88.9% [8/9] in females). This was followed in males by articular multifragmentary fractures (12.5% [2/16]) and in females by articular simple-metaphyseal multifragmentary fractures (11.1% [1/9]). Articular simple-metaphyseal multifragmentary fractures were the least frequent in males (6.3% [1/16]). In females, there was no incidence of articular multifragmentary group.



[Table 3] presents comparison of the pattern of distal humeral fractures between the right and left sides. The most frequent type of distal humeral fractures was extra-articular fractures (44.6% [25/56] on the right humerus and 54.5% [48/88] on the left humerus) followed by partial articular fractures (33.9% [19/56] on the right humerus and 30.7% [27/88] on the left humerus) while the least frequent type was the complete articular fractures (21.4% [12/56] on the right humerus and 14.8% [13/88] on the left humerus).
Table 3: Comparison of the pattern of distal humeral fractures between the right (n=56) and left (n=88) sides

Click here to view


Among the extra-articular fracture cases [Table 3], apophyseal avulsion fractures were the most frequent (56.0% [14/25] on the right humerus and 43.8% [21/48] on the left humerus), followed by the metaphyseal simple fractures (24.0% [6/25] on the right humerus and 35.4% [17/48] on the left humerus) while the metaphyseal multifragmentary fractures were the least frequent (20.0% [5/25] on the right humerus and 20.8% [10/48] on the left humerus).

Among the partial articular fracture cases [Table 3], sagittal lateral condyle fractures were the most frequent (68.4% [13/19] on the right humerus and 63.0% [17/27] on the left humerus) followed by the sagittal medial condyle fractures (31.6% [6/19] on the right humerus and 29.6% [8/27] on the left humerus). The frontal fractures were the least frequent on the left side (7.4% [2/27]). There was no incidence of frontal fracture on the right humerus.

Among the complete articular fracture cases [Table 3], articular simple-metaphyseal simple fractures were the most frequent (75.0% [9/12] on the right humerus and 92.3% [12/13] on the left humerus) followed on the right humerus by articular simple-metaphyseal multifragmentary fractures (16.7% [2/12]) and on the left humerus by articular multifragmentary fractures (7.7% [1/13]). Articular multifragmentary fractures were the least frequent on the right humerus (8.3% [1/12]). On the left humerus, there was no incidence of articular simple-metaphyseal multifragmentary fracture.

[Table 4] presents comparison of the pattern of distal humeral fractures among the various age groups. The most frequent type of distal humeral fractures was extra-articular fractures (50.0% [46/92] among the children, 42.3% [11/26] among the young ones, 66.6% [12/188] among the middle-aged, and 50.0% [4/8] among the elderly). This was followed, among the children and young by partial articular fractures (37.0% [34/92] among the children, 30.8% [8/26] among the young). Among the elderly, it was followed by complete articular fractures (37.5% [3/8]). The least frequent type among the children and young was the complete articular fractures (13.0% [12/92] among the children, 26.9% [7/26] among the young ones). Among the elderly, the least frequent was partial articular fractures (12.5% [1/8]). Among the middle-aged, partial articular and complete articular fractures had equal frequency (16.7% [3/18] each).
Table 4: Comparison of the pattern of distal humeral fractures among the various age groups

Click here to view


Among the children with extra-articular fractures [Table 4], apophyseal avulsion fractures were the most frequent (56.5% [25/46]) followed by metaphyseal simple fractures (32.6% [15/46]) while the least frequent were the metaphyseal multifragmentary fractures (10.9% [5/46]). Among the young with extra-articular fractures [Table 4], apophyseal avulsion and metaphyseal simple fractures had the highest but equal frequencies (36.4% [4/11] each) while metaphyseal multifragmentary fractures were the least frequent (27.3 [3/11]). Among the middle-aged with extra-articular fractures [Table 4], metaphyseal multifragmentary fractures were the most frequent (58.4% [7/12]) followed by metaphyseal simple fractures (33.3% [4/12]) while the least frequent were the apophyseal avulsion fractures (8.3% [1/12]). All the elders with extra-articular fractures [Table 4] had apophyseal avulsion fractures (100.0% [4/4]).

Among the children with partial articular fractures [Table 4], sagittal lateral condyle fractures were the most frequent (67.6% [23/34]) followed by sagittal medial condyle fractures (26.5% [9/34]) while the least frequent were the frontal fractures (5.9% [2/34]). Among the young with partial articular fractures [Table 4], sagittal lateral condyle fractures were the most frequent (62.5% [5/8]) followed by sagittal medial condyle fractures (37.5% [3/8]). Among the middle-aged with partial articular fractures [Table 4], sagittal medial condyle fractures were the most frequent (66.7% [2/3]) followed by sagittal lateral condyle fractures (33.3% [2/3]). The only elder with partial articular fracture [Table 4] had a sagittal lateral condyle fracture.

Among the children with complete articular fractures [Table 4], articular simple-metaphyseal simple fractures were the most frequent (83.3% [10/12]) followed by articular simple-metaphyseal multifragmentary fractures (16.7% [2/12]). There was no case of articular multifragmentary fracture. Among the young with complete articular fractures [Table 4], articular simple-metaphyseal simple fractures were the most frequent (87.7% [6/7]) followed by articular multifragmentary fractures (14.3% [1/7]). There was no case of articular simple-metaphyseal multifragmentary fracture. All the middle-aged with complete articular fractures [Table 4] had articular simple-metaphyseal simple fractures (100.0% [3/3]). Among the elderly with complete articular fractures [Table 4], articular simple-metaphyseal simple fractures were the most frequent (66.7% [2/3]) followed by articular multifragmentary fractures (33.3% [1/3]). There was no case of articular simple-metaphyseal multifragmentary fracture.

[Table 5] presents comparison of the pattern of distal humeral fractures caused by falls and those as caused by RTAs which were the two major causes of distal humeral fractures recorded. The most frequent type of distal humeral fractures was extra-articular fractures (48.5% [48/99] caused by falls and 57.5% [23/40] caused by RTAs) followed by partial articular fractures (34.3% [34/99] caused by falls and 22.5% [9/40] caused by RTAs) while the least frequent type was the complete articular fractures (17.2% [17/99] caused by falls and 20.0% [8/40] caused by RTAs).
Table 5: Comparison of the pattern of distal humeral fractures between the main causes

Click here to view


Among the extra-articular fractures caused by falls [Table 5], apophyseal avulsion fractures were the most frequent (56.3% [27/48]) followed by metaphyseal simple fractures (33.3% [16/48]) while the least frequent were the metaphyseal multifragmentary fractures (10.4% [5/48]). Among the extra-articular fractures caused by RTAs [Table 5], metaphyseal multifragmentary fractures were the most frequent (39.2% [9/23]) while apophyseal avulsion and metaphyseal simple fractures were equal in frequencies (30.4% [7/23] each).

Among the partial articular fractures caused by falls [Table 5], sagittal lateral condyle fractures were the most frequent (61.8% [21/34]) followed by sagittal medial condyle fractures (32.4% [11/34]) while the least frequent were the frontal fractures (5.9% [2/34]). Among the partial articular fractures caused by RTAs [Table 5], sagittal lateral condyle fractures were the most frequent (66.7% [6/9]) followed by sagittal medial condyle (33.3 [3/9]).

Among the complete articular fractures caused by falls [Table 5], articular simple-metaphyseal simple fractures were the most frequent (61.8% [21/34]) followed by articular simple-metaphyseal multifragmentary fractures (32.8% [11/34]) while the least frequent were the articular multifragmentary fractures (5.9% [2/34]). Among the complete articular fractures caused by RTAs [Table 5], articular simple-metaphyseal simple fractures were the most frequent (66.7% [6/9]), followed by articular simple-metaphyseal multifragmentary fractures (33.3% [3/9]).


  Discussion Top


The study presents pattern of distal humeral fractures among Nigerians. The most frequent type of distal humeral fractures was extra-articular fractures followed by partial articular fractures while the least frequent was the complete articular fractures. This pattern was seen in both sexes, on both sides, in both causes, and in all age groups except among the elderly in which complete articular fractures were the second most frequent while partial articular fractures were the least frequent.

It had been noted that in children, the supracondylar area is still in the process of remodeling and is therefore thinner with a more slender cortex, predisposing this area to fracture (Skaggs and Pershad, 1997). Fall had been recorded as the most common cause of these fractures (Cheng et al., 1999; Cheng et al., 2001; Ezeuko et al., 2014a). A fall onto an outstretched hand puts a hyperextension load on the arm. The distal fragment displaces posteriorly in over 95% of cases (Skaggs and Pershad, 1997). As the elbow is forced into hyperextension, the olecranon serves as a fulcrum and focuses the stress on the distal humerus causing fracture (Abraham et al., 1982). The rare flexion-type supracondylar fracture is often the result of a fall directly onto a flexed elbow.

This study also shows that among the extra-articular fracture cases, apophyseal avulsion fractures were the most frequent. This was the case in both sexes, on both sides, in fractures caused by falls and in all age groups with the exception of the middle-aged. Anatomically, apophyses of the distal humerus include the lateral epicondyle which is the common extensor origin of the forearm muscles and the medial epicondyle which is the common flexor origin of the forearm muscles. The high frequency of apophyseal avulsion fractures noted in this study could be attributed to the fact that apophyses are located at the site of attachment of major muscle tendons to bone and are subjected primarily to tensile forces (Caine et al., 2006). However, acute or chronic injuries affecting apophyses are not generally associated with disruption of longitudinal bone growth. This is because the apophyses contribute to bone shape but not to longitudinal growth (Garland, 1987).

Schatzker (2005) had noted that avulsion fracture of the lateral epicondyle is an extremely rare injury in adults that may occur as part of a posterolateral or posterior dislocation of the elbow. In the latter case, it is frequently associated with a fracture of the medial epicondyle. In children where the lateral epicondyle is avulsed with varying portions of the capitulum, it may turn on itself through 180° and turn the fracture surface outward, and the outcome may be a nonunion and deformity. This complication is not seen in adults. When the elbow is reduced, the epicondylar fragment reduces and heals in place, usually by bone, although occasionally by fibrous tissue (Schatzker, 2005).

On the contrary, fractures of the medial epicondyle are most common in children, but may be seen in adults either as a result of a direct injury or as an avulsion (Schatzker, 2005). The fragments may vary in size, displacement, and degree of comminution. Small and undisplaced fragment does not usually require surgical treatment. However, fragments that are displaced and caught in the joint, as may occur in the reduction of a lateral dislocation of the elbow, require surgical reduction, and fixation. Suture to the adjacent soft tissue is most often applied to comminuted fragments (Schatzker, 2005). Occasionally, the fragment may be quite large and displaced. Whenever displaced or comminuted, it is openly reduced and stabilized by internal fixation to prevent the onset of ulnar palsy using a medial approach. As a precaution, the ulnar nerve is identified and protected before the reduction is attempted (Schatzker, 2005).

The fact that among the middle-aged with extra-articular had metaphyseal multifragmentary fractures as the most frequent coupled with the fact that extra-articular fractures caused by RTAs had metaphyseal multifragmentary fractures as the most frequent could be attributed to the high level of mobility among this age group and their higher predisposition to RTAs. Other studies had noted that this age group consists of agile, active, and very mobile age range associated with increase transit from place to place, increase in risk-taking and it is the age range associated with increased use of alcohol and drug intoxication (Kumar et al., 2008; Silas et al., 2012; Ezeuko et al., 2014b).

In contrast to the more frequent apophyseal avulsion of the medial and epicondyles, lateral sagittal condyle fractures, fracture of the capitulum which were all noted to have good prognosis, the less frequent extra-articular metaphyseal simple and multifragmentary fracture as well as complete articular fractures of the distal humerus, all have poor prognosis (Schatzker, 2005). Failure of treatment of these fractures result in stiffness and pain in the elbow. Varus or valgus deformity, frequently seen following improperly treated supracondylar fractures in children, is not as significant a problem in adults as is stiffness (Schatzker, 2005).


  Conclusion Top


This study shows to a great extent that there is a pattern for distal humeral fractures among Nigerians irrespective of the sex or the side affected. This type of epidemiologic studies offers important data that contributes to improvement in fracture management and well-being of the patient. It also goes a long way in equipping surgeons, not only for enhancement of intrinsic stability fractures, but also to allow resources to be allocated on the basis of projected frequency of different types of distal humeral fractures. The ability to predict the level of admissions to a trauma center is valuable for administrative and training purposes.[19]

 
  References Top

1.
Abraham E., Powers T., Witt P., Ray R.D. (1982). Experimental hyperextension fractures in monkeys. Clin Orthop Relat Res 171:309-18.  Back to cited text no. 1
    
2.
Caine D., DiFiori J., Maffulli N. (2006). Physeal injuries in children's and youth sports: Reasons for concern? Br J Sports Med 40:749-60.  Back to cited text no. 2
    
3.
Cheng J.C., Lam T.P., Maffulli N. (2001). Epidemiological features of supracondylar fractures of the humerus in Chinese children. J Pediatr Orthop B 10 (1):63-7.  Back to cited text no. 3
    
4.
Cheng J.C., Ng B.K., Ying S.Y., Lam P.K. (1999). A 10-year study of the changes in the pattern and treatment of 6,493 fractures. J Pediatr Orthop 19 (3):344-50.  Back to cited text no. 4
    
5.
Ezeuko V.C., Ehimigbai A.R., Esechie E.L. (2014a). Risk factors associated with distal humeral fractures: A radiological study of Nigerians admitted at National Orthopedic Hospital, Igbobi, Lagos State, Nigeria. J Exp Clin Anat 13:5-11.  Back to cited text no. 5
    
6.
Ezeuko V.C., Anetor-Oforghor E., Enogieru A.B., Ogbeide O.U. (2014b). An Insight to Patterns of Femoral Diaphyseal Fractures Among Adult Nigerians: University of Benin Teaching Hospital Experience. J Anat Sci 5 (2):33-8.  Back to cited text no. 6
    
7.
Garland J.J. (1987). Fundamentals of Orthopedics. 5th ed. Saunders, Philadelphia.  Back to cited text no. 7
    
8.
Jupiter J.B., Mehne D.K. (1992). Fractures of the distal humerus. Orthopedics 15:825-33.  Back to cited text no. 8
    
9.
Kumar A., Lalwani S., Agrawal D., Rautji R., Dogra T.D. (2008). Fatal road accidents and their relationship with head injuries: An epidemiological survey of five years. Indian J Neurotrauma 5 (2):63-7.  Back to cited text no. 9
    
10.
Müller M.E., Nazarian S., Koch P., Schatzker J. (1990). The Comprehensive Classification of Fractures of Long Bones. Springer, New York.  Back to cited text no. 10
    
11.
Orthopaedic Trauma Association Committee for Coding and Classification. (1996). Fracture and Dislocation Compendium. J Orthop Trauma 10 Suppl 1:36-41.  Back to cited text no. 11
    
12.
Reich R.S. (1936). Treatment of intercondylar fractures of the elbow by means of traction. J Bone J Surg 18:997-1004.  Back to cited text no. 12
    
13.
Ring D., Jupiter J.B., Gulotta L. (2003). Articular fractures of the distal part of the humerus. J Bone Joint Surg Am 85:232-8.  Back to cited text no. 13
    
14.
Riseborough E.J., Radin E.L. (1969). Intercondylar fractures of the humerus in the adult. J Bone Joint Surg 51A: 130-41.  Back to cited text no. 14
    
15.
Schatzker J. (2005). Fractures of the distal end of the humerus (13-A, B, and C). In: Schatzker J., Tile M., editors. The Rationale of Operative Fracture Care. 3rd ed. Springer, Berlin, Heidelberg, New York, 103-21.  Back to cited text no. 15
    
16.
Silas O.A., Adoga A.A., Echejo G.O., Dauda A.M., Manasseh M.N., Olu-Silas R.A. (2012). Pattern of Injuries Associated with Deaths Following Road Traffic Accidents as Seen in a Tertiary Health Centre Jos University Teaching Hospital (JUTH), Jos, North Central, Nigeria. J Health Sci 2 (2):5-7.  Back to cited text no. 16
    
17.
Skaggs D., Pershad J. (1997). Pediatric elbow trauma. Pediatr Emerg Care 13 (6):425-34.  Back to cited text no. 17
    
18.
Wainwright A.M., Williams J.R., Carr A.J. (2000). Interobserver and intraobserver variation in classification systems for fractures of the distal humerus. J Bone J Surg 82:636-42.  Back to cited text no. 18
    
19.
Webb L.X. (2001). Fractures of the distal humerus. In: Bucholz R.W., Heckwan J.D., editors. Rockwood and Green's Fractures in Adults. Lippincott Williams and Williams, Philadelphia, 953-72.  Back to cited text no. 19
    


    Figures

  [Figure 1]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Materials and Me...
Results
Discussion
Conclusion
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed2186    
    Printed66    
    Emailed0    
    PDF Downloaded279    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]