Can adjunctive perioperative radiation improve range of motion after total knee revision for arthrofibrosis?

Background: Total knee arthroplasty revision (TKRev) can be performed to treat chronic arthrofibrosis. Low-dose irradiation may decrease fibro-osseous proliferation of soft tissue; therefore, it may be effective at increasing range of motion (ROM) after TKRev. Our hypothesis is that low-dose radiation administered in the immediate postoperative period leads to increased ROM after TKRev for arthrofibrosis.

Methods: A retrospective analysis was conducted from 2008-2015 on 26 patients who underwent TKRev for treating chronic arthrofibrosis. Fifteen patients (XRT group) received 800 cGy radiation within 48 hours after TKRev and 11 patients (CTL group) did not. Measurements of extension, flexion, and total arc of ROM were performed preoperatively and at one, six, and 12 months postoperatively.

Results: ROM improved from 14.3° extension, 69.0° flexion, and 54.7° total ROM preoperatively, to 3.3° extension, 94.0° flexion, and 90.7° total ROM postoperatively in the XRT group. ROM improved from 18.6° extension, 85.9° flexion, and 67.3° total ROM preoperatively to 4.1° extension, 102.5° flexion, and 98.5° total ROM postoperatively in the CTL group. The 1-year overall improvement in extension (12.5°), flexion (21.4°), and total ROM (33.9°) vs preoperative ROM was significant for all measurements (p < 0.001). The 8.4° improvement in flexion (25.0° vs 16.6°, p = 0.10) in the XRT group vs the CTL group approached, but did not reach significance.

Conclusions: TKRev for arthrofibrosis showed significant improvement in extension, flexion, and total ROM at one year. The use of low dose irradiation showed promise with improved flexion, but the result did not reach statistical significance in this small sample of patients.