A 24-month follow-up after treatment of hallux rigidus with resection arthroplasty in combination with a resorbable polymer-based implant and platelet-rich plasma.

BACKGROUND: Aim of this study was to analyze the clinical outcome after treatment of hallux rigidus with implantation of a resorbable polymer-based implant immersed with autologous platelet-rich plasma (PRP). METHODS: Forty-five patients with hallux rigidus were treated with three-stage resection arthroplasty and subsequent covering of the metatarsal head with a polyglycolic acid-hyaluronan implant immersed with autologous PRP. Patients were clinically assessed using the AOFAS rating scale preoperatively and at 12 and 24 month follow-up. Alignment and range of motion in the metatarsophalangeal joint was measured using a goniometer. RESULTS: The AOFAS rating scale and ROM showed significant (p<.01) improvement in all subcategories one and two years after surgery compared to the preoperative situation. CONCLUSIONS: Covering of the metatarsal head after resection arthroplasty with the PGA-hyaluronan implant immersed with autologous PRP is safe and leads to a notable improvement of the symptoms in patients with hallux rigidus.

Augmentation and repair tissue formation of the nucleus pulposus after partial nucleotomy in a rabbit model.

Disc degeneration alters disc height and mechanics of the spinal column and is associated with lower back pain. In preclinical studies gel-like materials or resorbable polymer-based implants are frequently used to rebuild the nucleus pulposus, aiming at tissue regeneration and restoration of tissue function. To compare the outcome of tissue repair, freeze-dried resorbable polyglycolic acid-hyaluronan (PGA/HA) implants without any bioactive components or bioactivated fibrin (fibrin-serum) was used in a degenerated disc disease model in New Zealand white rabbits. Animals with partial nucleotomy only served as controls. The T2-weighted/fat suppression sequence signal intensity in the nuclear region of operated discs as assessed by magnet resonance imaging was reduced in operated compared to healthy discs, indicating loss of water and did not change from week 1 to month 6 after surgery. Quantification of histological and immunohistochemical staining indicated that the implantation of PGA/HA leads to significantly more repair tissue compared to nucleotomy only. Type II collagen content of the repair tissue formed after PGA/HA or fibrin-serum treatment is significantly increased compared to controls with nucleotomy only. The data indicate that intervertebral disc augmentation after nucleotomy has a positive effect on repair tissue formation and type II collagen deposition as shown in the rabbit model.