Prediction Of Palmaris Longus Tendon Length And Thickness Through Simple Anthropometric Measurements.

Objective: This study aimed to test whether palmaris longus tendon (PLT) length and thickness can be predicted from simple anthropometric measurements.

Materials and methods: 120 healthy volunteers with bilateral PL muscles were enrolled in this prospective study. PLT length and thickness were measured by ultrasonographic examination. Anthropometric measurements included body height, weight, forearm length, and wrist circumference. Correlation, linear regression, and Bland-Altman plot were used for analysis.

Results: The mean PLT length and thickness were 10.8±1.4 cm and 4.0±0.9 mm, respectively. Body height and PLT length had a moderate positive correlation (r:0.407, p:0.001), and forearm length and PLT thickness had a weak positive correlation (r:0.229, p:0.001). The regression analysis showed that body height was the best predictor for PLT length, and forearm length was the best predictor for PLT thickness. The regression equations were as follows: PLT length=0.276+(0.062×height) (r2=0.165, p<0.001) and PLT thickness=1.373+(0.108×forearm length) (r2=0.052, p<0.001). The predicted PLT lengths and thicknesses were calculated using these regression formulas and compared with the actual thicknesses and lengths using the Bland-Altman plot. The upper and lower limits of agreement (95% CI) ranged from -2.54 cm to 2.51 cm for actual PLT length and predicted PLT length and from -1.76 mm to 1.74 mm for actual PLT thickness and predicted PLT thickness in the Bland-Altman plot with a weak agreement and proportional bias.

Conclusions: These findings indicate that height and forearm length have limited accuracy in predicting PLT length and thickness. The preoperative ultrasonographic examination can provide valuable assistance, particularly in cases that require grafts with precise length and thickness requirements.