Is intra-articular injection of autologous micro-fragmented adipose tissue effective in hip osteoarthritis? A three year follow-up

Background: Recently, increased attention on regenerative medicine and biological injective treatments have been proposed to restore native cartilage. Micro-fragmented adipose tissue (MFAT) has been studied for its anti-inflammatory, paracrine, and immunomodulatory effects. The long-term effects of MFAT are still poorly understood: the aim of the present study is to demonstrate how hip articular injections with autologous MFAT can have an impact on clinical outcomes. Methods: Seventy-one consecutive patients affected by early hip osteoarthritis underwent an ultrasound-guided hip injection of autologous MFAT between June 2017 and December 2018. Patients were divided into four groups according to the Oxford Hip Score. All patients received 4 mL of autologous micro-fragmented adipose tissue under an ultrasound guide. A clinical evaluation was done between 29 and 41 months after the initial treatment. During this follow-up period, we recorded any new treatment the patients had done, whether that be injection or arthroplasty surgery. Results: The study included 55 patients. Out of 55 patients, 28 saw benefits and were in no need of further treatment. Moreover, the score between the beginning and control increased by 6.9 points. Ten patients underwent a new articular injection: the mean time between the two injections was 635.7 ± 180 days. Seventeen patients underwent total hip replacement: the mean period between the autologous MFAT injection and the surgery was 495 days. Conclusion: This study found that intra-articular injections with autologous MFAT achieve beneficial clinical results in patients affected by early to moderate hip osteoarthritis, with an OHS between 48 and 30. Furthermore, these subjects are the ideal patients for whom this treatment obtains good clinical results.