Cartiva- Preserving great toe motion.
Hallux rigidus is the most common arthritic condition of the foot. There are only few surgical options that does not require fusing the 1st MTPJ thus allowing motion in the joint. A new first metatarsophalangeal (MTP) joint hemiarthroplasty with a polyvinyl alcohol (PVA) hydrogel implant (Cartiva) has demonstrated pain relief and functional outcomes equivalent to first MTP arthrodesis at 2- and 5-years post operation.
The Cartiva Synthetic Cartilage Implant is intended for use in the treatment of patients with painful degenerative or posttraumatic arthritis (hallux limitus or hallux rigidus) in the first metatarsophalangeal joint with or without the presence of mild hallux valgus, defined as a hallux valgus angle less than or equal to 20º (greater than 20º was an exclusion criteria in the clinical study).
Design and mechanism of action:
The Cartiva SCI device is a polymer-based biomaterial implant for treatment of first metatarsophalangeal joint osteoarthritis. The viscoelastic hydrogel implant’s material properties are conducive to replacing focal areas of damaged cartilage, providing pain reduction, and maintaining range of motion. The Cartiva SCI device does not regrow or replace cartilage.
The device is a molded cylindrical implant composed of polyvinyl alcohol and saline that is placed into the metatarsal head in the first metatarsophalangeal (MTP) joint via pressfit implantation. The Cartiva SCI device is implanted during a short and minimally invasive implantation procedure that allows for faster recovery, preservation of joint function compared to the surgical fusion of the MTP joint, and preserves the option for future surgical treatment in the event of complications.
The device, which is classified as a hydrated polymer, consists of water in similar proportion to human tissue. This organic polymer-based biomaterial is capable of withstanding repetitive loading typical of normal walking conditions, and its mechanical properties are similar to articular cartilage.
The Cartiva SCI device, a cylindrical device made from an elastic biomaterial, may be used as a replacement for damaged cartilage and bone without requiring the destruction or removal of a patient’s healthy tissue. It is intended for use during a single surgical procedure. The procedure is similar to that used for osteochondral autograft or allograft transplantation; a part is placed into a pre-drilled hole to resurface the damaged area of cartilage/bone. Cartiva SCI provides an alternative to tissue-based treatments without exposing the patient to the risk of viral transmission or an inflammatory response because it does not contain substances derived from human or animal tissue. Cartiva SCI is supplied in a range of sizes for selection by the physician.
Pre Cartiva implantation.
Cartiva in the head of the 1st MTPJ
Results (5 years of follow up):
Excellent survivorships- 96.2% implants retained at 5 years of follow up.
High satisfaction rate: 96% of patients would undergo procedure again.
A substantial and clinically meaningful reduction in pain using the Visual Analog Scale (VAS) was experienced by subjects in the Cartiva implant group at every follow-up visit through 2 years. Cartiva implant subjects demonstrated a 93% reduction from a median score of 68 at baseline to 5 at 2 years.
Functional activities were evaluated using the validated Foot and Ankle Mobility Measure (FAAM). Substantial improvement was observed for the Cartiva implant subjects throughout the 2-year follow-up period with a 168% median improvement observed in the sporting activities scale.
There was a substantial and clinically important improvement in median active dorsiflexion motion in the Cartiva implant group, restoring motion to levels which are documented in the literature to be needed for normal walking gait while experiencing substantial reduction in pain.