Partial Flexor Tendon Laceration Assessment: Interobserver and Intraobserver Reliability
Accurate assessment of partial-thickness flexor tendon lacerations in the hand is difficult owing to the subjectivity of evaluation.
In this study, we created 12 partial-thickness flexor tendon lacerations in a cadaveric hand, evaluated the accuracy of 6 orthopedic residents and 4 fellowship-trained hand surgeons in estimating the percentage thickness of each laceration, and assessed the groups’ interobserver and intraobserver agreement. The 10 participants estimated each laceration independently and on 2 separate occasions and indicated whether they would repair it. The actual thickness of each laceration was calculated from measurements made with a pair of digital microcalipers. Overall estimates differed significantly from calibrated measurements. Estimates grouped by residents and fellowship-trained hand surgeons also differed significantly. Third-year residents were the most accurate residents, and fellowship-trained hand surgeons were more accurate than residents. Overall interobserver agreement was poor for both readings. There was moderate overall intraobserver agreement. Fellowship-trained hand surgeons and first-year residents had the highest intraobserver agreement. These results highlight the difficulty in accurately assessing flexor tendon lacerations. Accuracy appears not to improve with surgeon experience.
Once the decision has been made to go to the operating room and the injury is being evaluated, what should be done with the information from the measurement, whether made with loupe magnification, calipers, rulers, or the naked eye? Surgeons must weigh the risks for triggering, entrapment, and rupture of untreated partial tendon lacerations1 with the added bulk and potential for adhesions, along with the tensile strength reduction that accompanies tendon repair. Both Reynolds and colleagues13 and Ollinger and colleagues14 found tensile strength significantly diminished in sutured tendons. Ollinger and colleagues14 showed a decrease in tendon gliding after surgical exposure and tenorrhaphy for partial tendon lacerations. Reynolds and colleagues13 concluded that surgical repair leads to poorer results than nonsurgical treatment.
Clinical studies have demonstrated excellent results with nonintervention, and in vivo and in vitro studies have indicated that early motion can be initiated in partial lacerations of up to 95% of total CSA. Wray and Weeks6 treated 26 patients with partial lacerations varying from 25% to 95% of total CSA and noted 1 incidence of trigger finger (which resolved) and no late ruptures. They advocated treatment with early motion and excision or repair of beveled partial lacerations with simple sutures. Stahl and colleagues2 reported comparable outcomes in children with partial lacerations up to 75% of total CSA treated with and without surgery and noted no complications in either group. In a biomechanical study, Hariharan and colleagues4 found lacerations up to 75% can withstand forces associated with active unresisted mobilization.
Conversely, how many patients or surgeons want to return to the operating room to fix a late rupture when it could have been repaired in the primary setting? Schlenker and colleagues,1 reporting on a late flexor pollicus tendon rupture that required tendon grafting, recommended exploration and primary repair of all partial flexor tendon lacerations. Often, it is difficult to determine whether surgical repair is necessary to ensure the best outcome for the patient.
Our study results showed that, in the evaluation of flexor tendon lacerations, both accuracy and interobserver agreement were poor among residents and fellowship-trained hand surgeons, and intraobserver agreement was moderate. Third-year residents were the most accurate residents, and there was no difference in accuracy between residents and fellowship-trained hand surgeons. Our results highlight the difficulty in making accurate assessments of flexor tendon lacerations owing to the subjectivity of evaluation, which appear not to improve with surgeon experience.
