Introduction
Fractures of distal humerus are relatively uncommon injuries in adults and are very challenging to manage. Approximately 7% of the adult fractures involves the elbow, of which about one-third involve the distal humerus [1,2]. The proximity of neurovascular structures, the frequent occurrence of metaphyseal bone loss and significant articular comminution, and the unforgiving tendency of the elbow toward capsular stiffness and heterotopic ossification make these fractures often difficult to treat [3,4].
Overall incidence of distal humerus fracture is increasing, mimicking the increasing incidence of hip, proximal humerus and wrist fractures [5]. Historically, these injuries were treated by means of closed reduction and slinging (the so called "bag of bones" technique) because the results of open reduction and internal fixation were poor [6].
Advances in the techniques of open reduction and internal fixation and newer implants along with the goal of anatomic restoration and early mobilization, the standard of care has now shifted to surgical treatment of these injuries by open reduction and internal fixation. The ultimate surgical goals are stable facture fixation and early mobilization of elbow [7].
Depending upon the severity of communition and displacement, open reduction and internal fixation can be done with locking plates, reconstruction plates, cannulated cancellous screws (C.C. screws), kirschner wire or tension band wiring. The introduction of anatomical pre-contoured locking plate technology approximately a decade ago, ushered in the latest advances for the management of distal humerus fractures, offered enhanced biomechanical properties and more robust fixation, thus allowing early rehabilitation.
Controversy persists, whether standard non-locking plate screws construct well-placed to maximize subchondral buttressing performs better than locking screws placed through the factory preset trajectories which are often distant from and not parallel to the articulation of the distal humerus. Further long term, clinical benefits of locking plate fixation for distal humerus fractures are not known [8].
The aim of this study was to compare and evaluate the results of pre-contoured locking plates and conventional reconstruction plates in management of AO type C distal humerus fractures in adults with regard to functional outcome using Mayo Elbow Performance Score (MEPS) and radiological outcome in terms of rate of union.
Materials and Methods
This randomized prospective study was done comparing patients with intra-articular distal humerus fractures AO type C treated either by pre-contoured locking plates or conventional reconstruction plates after getting approval from institutional ethical committee and written consent from all patients. Fractures were classified using the AO/OTA classification system on the basis of preoperative X-rays and CT scans.
All AO type C distal humerus fractures, with age more than 18 years were included in the study. Open fractures, pathological fractures, fractures with neuro-vascular injury and associated fracture of ipsilateral upper limb were excluded from the study.
All the fractures were treated with definitive open reduction and internal fixation (ORlF) within 3 days. For the surgical procedure, the patients were placed in the lateral position with the involved arm supported and forearm hanging allowing at least 90° flexion.
In all patients, posterior approach along with Chevron osteotomy of the olecranon was done. The ulnar nerve was explored routinely; however, transposition was only performed in those patients where mechanical irritation seen by medial plate, was a concern.
After temporary reduction and fixation with K-wires, osteosynthesis using either the anatomically pre-contoured locking compression plates or 3.5mm reconstruction plates were used for both the columns. The patients were randomly randomized into these groups. Olecranon osteotomy was fixed with cannulated cancellous screws or tension band wiring (Figure 1).
Postoperatively, the elbow was splinted in 90° flexion and the limb was kept elevated to decrease swelling and patient was encouraged to move their fingers. Intravenous antibiotics were continued till post-operative day 2. Suction drain was removed after 48 hours and wound inspection was done at 2nd and 5th post-operative day.
Oral antibiotics and analgesics were given to the patient till the time of suture removal. Sutures/staples were removed on the 12th postoperative day. At 2 weeks POP slab was removed and patient was given arm pouch and active elbow and shoulder range of motion exercises were started as per patients pain tolerance.
Patients were instructed to carry out physiotherapy in the form of active elbow flexion-extension and pronation-supination. Patients were advised not to lift heavy weight or exert the affected upper limb.
Patients were followed up regularly at 6 weeks, 3 months, 6 months and 12 months post-operatively. At each follow up, patients were assessed subjectively for pain, swelling and restriction of joint motion.
The functional assessment of the patient was done according to Mayo elbow performance score and radiological assessment done for union. The results were statistically analyzed using Mann Whitney U test and a level of p < 0.05 was considered significant.
Results
A total of 25 patients (18 men and 7 women) were included in this study. The baseline characteristics of the patients in both groups are given in Table 1. The mean age of patients was 35 years (range 18 to 75 years). The dominant arm was involved in 16 fractures (16/25).
