Freezing nerves prior to knee replacement improves outcomes
The first study of its kind has found that freezing nerves before knee replacement surgery combined with traditional pain management approaches significantly improves patient outcomes. The results of the preliminary retrospective study, led by researchers at New Orleans School of Medicine, were published online in The Knee.
A retrospective chart review was carried out to investigate the cases of 100 patients with advanced osteoarthritis requiring total knee replacement in Vinod Dasa’s LSU Health New Orleans orthopaedic practice. Half of them were treated with standard multiple pain management options, before cryoneurolysis (nerve freezing) was introduced to the practice. The first 50 patients to undergo cryoneurolysis in addition to multimodal pain management comprised the treatment group, which was compared to the control group who had standard therapy alone. The treatment and control groups were similar in terms of gender, age and body mass index, the only difference being that the treatment group received cryoneurolysis via an FDA-approved handheld device five days prior to surgery.
The KOOS (Knee Injury and Osteoarthritis Outcome Score), PROMS (Patient-reported Outcomes Measurement Information System), WOMAC (Western Ontario and McMaster Universities Arthritis Index) and Oxford Knee Score were used to measure outcomes.
“Patients in the treatment group had significantly shorter hospital stays, were prescribed significantly fewer opioids during the first 12 weeks post-operatively and had significantly fewer knee symptoms,” noted Dasa, associate professor of clinical orthopaedics at LSU Health.
The potential to decrease hospital length of stay following total knee replacement could substantially reduce costs for hospitals. In the study, only 6 per cent of patients treated with cryoneurolysis before surgery stayed in the hospital for two or more days, compared with 67 per cent of patients who did not receive treatment. Almost half of patients treated with nerve freezing were discharged on the same day of surgery, compared with only 14 per cent in the control group. The shorter length of stay of the patients in the treatment group may be due to better local control of pain and a reduced need for nerve blocks that can impair motor function, as well as reduced use of opioids for pain control, which allows patients to walk and function well enough to go home sooner.
Reference: Dasa, V., Lensing, G., Parsons, M., et al. (2016) Percutaneous freezing of sensory nerves prior to total knee arthroplasty. The Knee doi: 10.1016/j.knee.2016.01.011