Internal fixation of unstable proximal humerus fractures with an anatomically preshaped interlocking plate: a clinical and radiologic evaluation.
BACKGROUND
We evaluated the outcome after internal fixation of unstable or displaced proximal humerus fractures with a new fixed-angle implant.


METHODS
Prospective consecutive study with a 1-year clinical follow-up in 119 of 137 patients (87%; mean 68 +/- 15 years; 31 two-, 47 three-, and 41 four-part fractures).


RESULTS
One year postoperatively, the range of motion of the injured side demonstrated on average four-fifths of the function of the contralateral side. Ninety-five percentage of patients (n = 114) could dress themselves independently with no or only slight restriction. The mean disabilities of the arm, shoulder, and hand score was 21 (range, 0-62). The absolute and relative Constant score significantly (p < 0.001) improved from 56 +/- 18 (75% +/- 21%) at 6 months postoperatively to up to 65 +/- 18 (82% +/- 18%) at 12 months postoperatively. The initial fracture configuration did not have a significant influence on clinical outcome or complications. Twenty-six patients (22%) underwent a reintervention because of a clinical problem or subjective complaint, which led to total or relevant relief of problems in 23 patients (87%). Radiologic follow-up revealed a significant correction of the mean fragment angles (p < 0.001) postoperatively compared with initial postcrash radiographs. The precision of intraoperative reduction had a significant impact on the patient's disabilities of the arm, shoulder, and hand scoring (p = 0.02). A comparison of the last evaluable radiographs with the intraoperative intensifier images revealed a mean loss of reduction over time of </=2 degrees.


CONCLUSIONS
The angular stability of the fixed-angle interlocking plate could be proven radiologically in this clinical series. This fixation system seems to be a promising alternative in the treatment of displaced or unstable proximal humerus fractures. Clinical outcome can be further improved by avoiding certain minor errors in operative technique.
Hirschmann
Michael Tobias
MT
Orthopedic Department, Kantonsspital Bruderholz, Bruderholz, Switzerland.
Quarz
Volker
V
Audigé
Laurent
L
Ludin
Dietmar
D
Messmer
Peter
P
Regazzoni
Pietro
P
Gross
Thomas
T
D000203:Activities of Daily Living; D000368:Aged; D001860:Bone Plates; D005260:Female; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal / Q000379:methods*; D006801:Humans; D016015:Logistic Models; D008297:Male; D010147:Pain Measurement; D011859:Radiography; D016059:Range of Motion, Articular; D012784:Shoulder Fractures / Q000145:classification / Q000000981:diagnostic imaging / Q000601:surgery*; D013997:Time Factors