Accuracy of Visual Estimates of Partial Flexor Tendon Lacerations

To determine whether hand surgeons could accurately and consistently estimate the size of partial flexor tendon lacerations.

Thirty-two partial flexor tendon lacerations were made in the flexor digitorum profundus tendons of a fresh-frozen cadaveric hand. Four hand surgeons and 5 residents estimated the size of the lacerations. Estimates were repeated 3 days later. Magnified images of the laceration cross-section were used to calculate the true size of each laceration. Inter- and intrarater reliability were calculated using the intraclass correlation coefficient. Accuracy was measured with the mean bias error and the mean absolute error.

Interrater and intrarater reliabilities were both high. There was a high level of consistency for both surgeons and residents. In terms of accuracy, there was a 3% bias toward underestimation. The mean absolute error was 11%. There was no statistically significant difference between the accuracy of attending hand surgeons and that of residents. Participants were less accurate when estimating lacerations close to a 60% laceration threshold for surgical repair (lacerations in the 50%-70% range). For lacerations within this range, an incorrect management decision would have been made 17% of the time, compared with 7% of the time for lacerations outside that range.

The accuracy and reliability of surgeon estimates of partial flexor tendon laceration size were high for surgeons and residents. Accuracy was lower for lacerations close to the threshold for repair.

Visual estimation is acceptable for evaluating partial flexor tendon lacerations, but it may be less reliable for lacerations near the threshold for repair. Therefore, surgeons should be cautious when deciding whether or not to repair partial lacerations in the borderline range.