A New Procedure for Ultrasound-Guided Hydrorelease for the Scarring After Arthroscopic Knee Surgery.

Postoperative scarring is one of the complications after arthroscopic knee surgery, which is usually treated with manual therapy or arthroscopic debridement. The incidence of symptomatic scarring requiring surgery within six months postoperatively has been reported to be approximately 0.06-6.00%. We treated a patient after arthroscopic surgery with a new "ultrasound-guided hydrorelease" procedure and we describe it. A 50-year-old woman with a history of arthroscopic anterior cruciate ligament reconstruction of the right knee presented to our clinic 10 months ago with a complaint of right anterior knee pain. Ultrasound imaging showed an infrapatellar fat pad (IPFP) scarring and sliding defects. The pre-treatment Kujala scale was 62 points and the visual analogue scale was 72. The inferolateral side of the patella was palpated to identify the scarring after arthroscopy at the IPFP area. An ultrasound probe was applied vertically to identify the site of adhesion of interest. Ultrasound-guided hydrorelease was performed using 7.0mL saline injected by needle (22G, 60mm) directed at the site with hypoechoic changes in the IPFP. After the procedure, the normalization of the IPFP sliding was confirmed by an ultrasound image. Four weeks after this procedure, the patient improved, with a Kujala scale of 82 points and a visual analogue scale of 28. The most important finding from this patient's course is that her chief complaint of anterior knee pain improved by ultrasound-guided hydrorelease into the IPFP scarring after arthroscopic knee surgery. The procedure should be considered as a treatment for scarring after arthroscopic knee surgery.