Background: Closed reduction and percutaneous pin fixation is the
treatment of choice for completely displaced (type-III) extension
supracondylar fractures of the humerus in children, although controversy
persists regarding the optimal pin-fixation technique. The purpose of this
study was to compare the efficacy of lateral entry pin fixation with that of
medial and lateral entry pin fixation for the operative treatment of
completely displaced extension supracondylar fractures of the humerus in
children.
Methods: This prospective, randomized clinical trial had sufficient
power to detect a 10% difference in the rate of loss of reduction between the
two groups. The techniques of lateral entry and medial and lateral entry pin
fixation were standardized in terms of the pin location, the pin size, the
incision and position of the elbow used for medial pin placement, and the
postoperative course. The primary study end points were a major loss of
reduction and iatrogenic ulnar nerve injury. Secondary study end points
included radiographic measurements, clinical alignment, Flynn grade, elbow
range of motion, function, and complications.
Results: The lateral entry group (twenty-eight patients) and the
medial and lateral entry group (twenty-four patients) were similar in terms of
mean age, sex distribution, and preoperative displacement, comminution, and
associated neurovascular status. No patient in either group had a major loss
of reduction. There was no significant difference between the rates of mild
loss of reduction, which occurred in six of the twenty-eight patients treated
with lateral entry and one of the twenty-four treated with medial and lateral
entry (p = 0.107). There were no cases of iatrogenic ulnar nerve injury in
either group. There were also no significant differences (p > 0.05) between
groups with respect to the Baumann angle, change in the Baumann angle,
humerocapitellar angle, change in the humerocapitellar angle, Flynn grade,
carrying angle, elbow flexion, elbow extension, total elbow range of motion,
return to function, or complications.
Conclusions: With use of the specific techniques employed in this
study, both lateral entry pin fixation and medial and lateral entry pin
fixation are effective in the treatment of completely displaced (type-III)
extension supracondylar fractures of the humerus in children.
Level of Evidence: Therapeutic Level I. See Instructions
to Authors for a complete description of levels of evidence.