The inflammatory response is mainly due to the presence of pro-inflammatory cytokines in the
synovium; in fact, it has been shown that there is an inverse relationship between the amount
of the pro-inflammatory cytokine IL-6 in the joint in patients undergoing TKA and the
patient's functional recovery one month after surgery. It has also been shown that a high
concentration in synovial fluid of catabolic factors, such as TNF-α, MMP-13 and IL-6, is
predictive of a lower resolution of pain 2 years after prosthesis surgery. Sellam and
Berenbaum emphasise the importance of considering the synovial membrane as a promising target
for new therapeutic strategies to control inflammation and thus prevent joint problems or
resolve clinical symptoms . There is an increasing need to find a local anti-inflammatory
treatment to be implemented in the immediate post-surgery period to avoid chronic pain. Not
only the pain condition, but also the functional condition, although better than the starting
condition, cannot be considered completely satisfactory; 37% of patients one year after
surgery have not achieved a complete functional recovery.
Extensive translational research has shown that biophysical stimulation with I-ONE® therapy
(Pulsed Electromagnetic Field by IGEA SpA, Carpi, Italy) is able to modulate cartilage
metabolism by increasing the reduction of the release of inflammation mediators involved in
cartilage degeneration, such as inflammatory cytokines (IL-6 and IL-8) and lipid mediators of
inflammation (prostaglandins E2), enhances the anti-inflammatory effect of individual
adenosine agonists A2A and A3 by increasing the release of the anti-inflammatory cytokine
IL-10.
In the clinic, I-ONE® therapy is able to prevent and/or slow down the degenerative phenomena
that accompany surgery in patients with cartilage lesions treated with microfractures under
arthroscopy in the knee or ankle, both in patients undergoing autologous chondrocyte
transplantation in the presence of scaffolds at the knee , and in patients with osteochondral
lesions of the talus, treated by graft transplantation, with addition of bone marrow
concentrate. I-ONE® therapy has also proven effective in patients undergoing total knee
replacement with or without patella prosthesis and after reverse shoulder replacement
surgery.
Postoperative noninvasive therapy with the use of PEMF in patients with painful TKA resulted
in significant improvement in pain and functional recovery, as demonstrated by the
preliminary results of this prospective cohort study.
The study plans to recruit patients with painful TKA whose pain occurred from at least 30
days after surgery to a maximum of 180 days after surgery. All patients will be instructed to
use local non invasive biophysical therapy with I-ONE® therapy (1.5 mT, 75 Hz) for 4 hours a
day for 60 days. Clinical evaluations such as Visual Analog Score (VAS), SF-12 Health Survey
(SF-12), EuroQol (EQ-5D) are scheduled at 1 month, 2, 6, 12 and 24 months after PEMF
treatment; Knee Society Score (KSS) is scheduled at 3 months of follow-up. The use of
nonsteroidal anti-inflammatory drugs (NSAIDs) is also recorded. Patients will be analyzed
into three different groups based on the time elapsed between surgery and the beginning of
PEMF therapy: Group 1 (30-90 days), Group 2 (91-150 days) and Group 3 (151-180 days).