PURPOSE OF THE STUDY: The aim of the study was to compare two surgical methods 
of treating diaphyseal fractures of the humerus.
MATERIAL AND METHODS: A prospective randomised study on the surgical treatment 
of humeral diaphyseal fractures was carried out between September 2009 and 
January 2013. The patients indicated for surgical treatment fell into two groups 
according to the technique used as follows: minimally invasive plate 
osteosynthesis (MIPO) with a locking compression plate (LCP; Synthes, 
Switzerland); depending on the fracture type and course of fracture line, either 
a straight narrow or a Philos or a metaphyseal LCP was used (group 1); and 
intramedullary nailing (EHN, Synthes, Switzerland) (group 2). A total of 49 
patients were entered into the study. The men-to-women ratio was about 1:1 and 
the average age was 52 years (18 to 83). Of them, 45 patients with 46 humeral 
fractures were followed up and evaluated. The injury was caused by a fall from 
standing or while walking (n=21), traffic accident (n=16), sports activity (n=3) 
or work-related activity (n=5). A single injury was treated in 72% and multiple 
trauma in 28% of the patients. Using the AO classification, fractures were 
diagnosed as types A, B and C in 25, 10 and 11 patients, respectively. The 
patients were randomised into the groups using a computer programme allowing for 
the maintenance of group homogeneity. Each patient received information on the 
method to be used in a sealed envelope.
RESULTS: The average injury-surgery interval was 6 days (range, 0 to 26). The 
average operative time was 128 minutes (80 to 200). The average intra-operative 
exposure to X-ray was 8 minutes (3 to 20). The average hospital stay was 20 days 
(4 to 100) The average rehabilitation time till functional recovery was 17 weeks 
(3 to 37), the time of bone union by radiographic assessment was 20 weeks (12 to 
40). The functional outcome was assessed using the Constant-Murley (CM) and 
Liverpool Elbow Score (LES) systems. The relative CM/LES score, as compared with 
the healthy extremity, was 95/100. Excellent and good results were achieved in 
89% and complications were recorded in 26% of the patients. The most frequent 
complication was impingement syndrome or prolonged rehabilitation both in the 
patients with proximal humerus fractures managed with the Philos locking plate 
and in those treated by intramedullary nailing, although this was not 
necessarily due to a technical error, i.e., osteosynthetic material protrusion. 
Iatrogenic radial nerve injury was found only in one patient treated by 
intramedullary nailing and was associated with traction during reduction and 
nail insertion. Pseudoarthrosis was recorded in one patient of each group and 
there were no infectious complications.
DISCUSSION: Intramedullary nailing has not yet shown such good outcomes in 
humeral as in tibial fractures. The results of metaanalysis have indicated that 
humeral fractures treated by plate osteosynthesis have fewer complications and 
require repeat surgery less frequently. However, as shown by most recent 
studies, this difference is getting smaller. The MIPO technique was adopted at 
our department several years ago and the aim was to compare our results with 
those of other centres. The studies so far published have show that MIPO and 
conventional open plate osteosynthesis give comparable outcomes. CONCLUSIONS The 
statistical evaluation using the unpaired t-test did not show any significant 
differences in either the functional results or the number of complications 
between the two methods. Both achieved about 90% of excellent and good results 
and had 26% of complications. The only significant difference was found in the 
length of operative time (136 min in MIPO versus 117 min in EHN). With use of 
the Chi-Square test, a significant correlation between AO fracture type and 
treatment outcome in the MIPO group was found, i.e., no poor result was recorded 
for type A fractures, as assessed by the CM/LES score. No such correlation 
between the fracture type and the functional outcome was seen in the EHN group.