A simple method to minimize limb-length discrepancy after hip arthroplasty.
BACKGROUND
Limb-length discrepancy is not uncommon after total hip arthroplasty. To minimize such discrepancies, we introduced a simple method to select an appropriate modular head during surgery.


METHODS
We used this method in 45 hips, and compared the outcome with that of a historical control group of 47 hips. Both groups received cement-less femoral components with modular heads of 4 different neck lengths. In the study group, we calculated the ideal distance between the center of the modular head and lesser trochanter on a preoperative AP radiograph. During surgery, we measured the actual distance between the center of trial heads and the lesser trochanter with a ruler, and selected the head in which the measured distance was closest to this distance. In the control group, we had selected a modular head based on preoperative planning.


RESULTS
The study group had a smaller mean postoperative limb-length discrepancy (2 (SD 2) mm) than the controls (7 (SD 4) mm).


CONCLUSIONS
This simple technique reduces limb-length discrepancy after cementless total hip arthroplasty.
Matsuda
Kenta
K
Department of Orthopaedic Surgery, Teikyo University School of Medicine, Tokyo, Japan.
Nakamura
Shigeru
S
Matsushita
Takashi
T
D000077:Acetabulum / Q000033:anatomy & histology / Q000601:surgery; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007870:Leg Length Inequality / Q000209:etiology / Q000517:prevention & control / Q000601:surgery; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome