Return of an Intact Hook Test Result: Clinical Assessment of Biceps Tendon Integrity After Surgical Repair

BACKGROUND: The hook test is a sensitive and specific tool that has been previously described for diagnosing distal biceps tendon ruptures in an efficient, cost-effective manner. However, its application in postoperative evaluations after surgical repair of distal biceps tendon ruptures is not documented. HYPOTHESIS/PURPOSE: We hypothesized that the hook test result returns to normal at some point postoperatively after distal biceps repair. This information could be used in decision making during follow-up examinations with both normal and abnormal findings. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: We retrospectively reviewed records of distal biceps repair. Between July 1, 2003, and July 1, 2016, a total of 56 patients underwent distal biceps repair and also had clear documentation of the results of the hook test during the postoperative period. Hook test results consisted of “intact,” “abnormal,” or “absent.” The timing of the return to a normal hook test result was recorded. RESULTS: Overall, 51 of 57 (89%) repairs were documented to have the hook test result return to “intact.” The test result returned to intact by a mean of 10 weeks after surgery (range, 2 weeks to 15 months). The biceps tendon was intact according to the hook test at the 4-month follow-up in 45 of the 51 patients (88%) in whom it ultimately returned. The hook test result was abnormal in 5 repairs in 5 patients with only a short-term follow-up, ranging from 2 to 7 weeks postoperatively. One patient with an abnormal hook test result at 2 weeks postoperatively underwent revision and was confirmed to have a partial tear of the biceps insertion. His hook test result returned to intact 3 months after revision repair. CONCLUSION: The hook test result returns to normal in patients who undergo distal biceps repair in the primary and revision settings with adequate follow-up. The vast majority of patients have a normal hook test result by 4 months postoperatively. An abnormal hook test result at 4 months postoperatively may indicate a failed repair and should prompt further investigation.