Emerging research and clinical experience suggest that metatarsal head resurfacing can be a viable option for facilitating pain relief in patients with hallux rigidus.
The HemiCAP® system (Arthrosurface) allows podiatric surgeons to treat localized cartilage lesions and major joint defects that cause toe joint pain, according to the manufacturer. Comprised of three-dimensional mapping technology, a set of instruments to map and prepare the damaged area, and a chrome and titanium implant, the HemiCAP system enables one to precisely align the surface of the implant to the contours of the patient’s articular cartilage surface.
The mapping technology of the HemiCAP system is particularly advantageous, according to Brian Carpenter, DPM, FACFAS, an Associate Professor in the Department of Orthopaedics at the University of North Texas Health Science Center in Fort Worth, Texas.
“The mapping technology allows us to intraoperatively define the surface curvatures of the metatarsal head, make decisions about implant placement and select from a range of implant surface curvatures to optimize fit,” explains Dr. Carpenter. “Building on this technology, we have developed further understanding of certain aspects of the joint that have been oversimplified with previous generations of implants.”
Stephen Kominsky, DPM, FACFAS, has performed approximately 75 procedures with the HemiCAP system and has been happy with the results.
“This implant does not disrupt the intrinsic muscles to the first MPJ,” points out Dr. Kominsky, who has been in practice for nearly three decades. “(The implant) maintains the insertion of the flexor hallucis brevis along with the sesamoid apparatus. This allows for the stability of the joint and the hallux to remain intact.”
Dr. Kominsky says placement of the HemiCAP implant also allows for decompression of the first MPJ space when necessary.
“In the majority of hallux rigidus cases, there is a narrowing of the joint space due to either an elevated first metatarsal or a long first metatarsal,” notes Dr. Kominsky, who is in private practice in Washington, D.C. “In either case, decompression of the joint with placement of the HemiCAP device can easily be accomplished. This translates into a greater range of motion. Increased range of motion, especially in dorsiflexion, will decrease the pain reported by the patient. No other implant for the first MPJ presents these advantages.”
In a recent study published in the Journal of Foot and Ankle Surgery, Dr. Carpenter and colleagues reported on mid-term follow-up results of the HemiCAP implant in 30 patients with either grade III or grade II hallux rigidus.1 In the study, in which there was an average follow-up of 27.3 months, Dr. Carpenter and his colleagues found a high degree of patient satisfaction with the results, and no implants had to be revised or removed.
“Initially, I was using the HemiCAP system for only advanced stage II and stage III hallux rigidus. I have expanded this into some of the stage IV hallux rigidus patients over the last year and have had great results,” adds Dr. Carpenter.
When it comes to postoperative care, Dr. Carpenter says “early weightbearing and aggressive range of motion exercises are essential.” Dr. Kominsky concurs. He tries to get these patients into sneakers at two weeks postoperatively and has them begin aggressive physical therapy at that time.
Editor’s note: For further reading, see “A Guide To First MPJ Head Resurfacing” in the August 2008 issue of Podiatry Today.
1. Carpenter B, Smith J, Motley T, Garrett A. Surgical treatment of hallux rigidus using a metatarsal head resurfacing implant: mid-term follow-up. J Foot Ankle Surg. 2010; 49(4):321-5.