Innovative hyaluronan/gellan gum/hydroxypropyl methyl cellulose membrane for prevention of adhesion in postoperative achilles tendon

A novel anti-adhesion barrier membrane composed of FDA-approved hyaluronan (HA), gellan gum (GG), and hydroxypropyl methylcellulose (HPMC) was developed to prevent postoperative tendon adhesion in our study. Seprafilm, a commercial hydrogel barrier membrane comprising HA and carboxymethyl cellulose (CMC), is effective in abdominal surgeries to reduce postoperative adhesions between the abdominal wall and underlying tissues. However, it is fragile, difficult to handle, and degrades rapidly, limiting its barrier function. Our HA/GG/HPMC (HGH) membrane overcame these drawbacks, exhibiting superior resilience, hydrophilicity, water content, swelling ratio, and stress-strain properties compared to the HG (HA/GG) and Seprafilm membranes. The HGH membrane was highly hydrophilic and reached hydration equilibrium within 3 min, enabling it to wrap tendons snugly without sticking or tearing. It degraded more slowly (60% mass remaining after 12 days <i>in vitro</i>, <i>vs.</i> 15% for Seprafilm after 4 days), providing an extended protective presence during the tendon's healing period. In a rat Achilles tendon repair model, the HGH membrane significantly reduced peritendinous adhesions and facilitated better healing histologically. The repaired tendon breaking strength after 3 weeks was significantly higher in the HGH group (37.5 N) than in the untreated (6.5 N), HGC (16 N), or Seprafilm (15.5 N) groups. Haematoxylin and eosin staining indicated that the HGH membrane resulted in significantly less tendon-tissue adhesion and superior healing. In summary, the HGH membrane degraded more slowly, was less fragile, more resilient, and more hydrophilic, making it easier to handle during surgery and thus an effective candidate for preventing adhesions in tendon surgery.