Capsular interposition arthroplasty offers an option over fusion for hallux rigidus

The procedure maintains motion in the first metatarsophalangeal joint brings high satisfaction rates.

Issue: December 2006

Researchers have again found successful outcomes with capsular interposition arthroplasty for grade 3 hallux rigidus in the longest follow-up study on the procedure.

Seth Robert Queler, MD
Seth Robert Queler

At an average follow-up of 22 months, patients increased an average of 29 points on the American Orthopaedic Foot and Ankle Society (AOFAS) Hallux Metatarsophalangeal-Interphalangeal Scale, and 82% of them were satisfied with their results and would undergo the procedure again, according to Seth Robert Queler, MD, of Mineola, N.Y.

Although fusion remains the gold standard procedure for severe hallux rigidus, capsular interposition arthroplasty provides a surgical option for maintaining the first metatarsophalangeal (MTP) joint and resurfacing the joint surface.

Most specifically, Queler said, this procedure is indicated for patients who want to retain motion in their first MTP joint – not an option with fusion – including athletes who play lunging-type sports, such as tennis. The procedure also provides women the option of wearing shoes with a one-inch heel or higher.

But this procedure may be just a temporary fix. “I would recommend [capsular interposition arthroplasty] with the understanding that there is a chance that [patients] might need fusion down the line,” Queler told Orthopedics Today. “Even though none of our patients went on to fusion, two of the patients were not happy.”

Incision for capsular interposition arthroplasty
A single surgeon performed capsular interposition arthroplasty for all the patients in this series. This image demonstrates the typical incision for this type of procedure. The surgeon pinned the first ray into place, and inserted the capsule and extensor hallucis brevis in the first metatarsophalangeal joint.

Images: Queler SR

Queler performed this investigation while a fellow at Philadelphia Orthopaedic Foot and Ankle Surgeons.

He and the researchers evaluated 11 patients (11 feet) who underwent capsular interposition arthroplasty between 2001 and 2005.

The patient group included one man and 10 women. They were an average age of 59 years.

Queler presented the study results at the American Orthopaedic Foot and Ankle Society’s 22nd Annual Summer Meeting.

Initial treatment

Surgeons initially treated all patients conservatively with orthotic devices; shoe modifications, such as stiff-soled shoes; and NSAIDs.

Patients went on to surgical treatment with capsular interposition arthroplasty if they had clinical and radiographic evidence of severe hallux rigidus, if they complained of constant pain or if they had severe range of motion restriction in the first MTP joint.On preoperative X-rays, patients also demonstrated extensive osteophytes around the first metatarsal head and the base of the proximal phalanx – some with loose bodies – and they had severe joint space narrowing. A single surgeon performed the procedures, using the technique introduced by William G. Hamilton, MD and colleagues in 1997.

Clinical results

Researchers evaluated the patients between 9 months and 54 months postoperatively. At preop, the average AOFAS score was 51 (range, 35 to 64) with an average score of 15 for pain.

The AOFAS score increased to an average score of 80 (range, 65 to 96) with an average pain score of 30 at postop. Nine patients (82%) reported they were satisfied with the surgery and said they would undergo the procedure again.

The decision to perform capsular interposition arthroplasty depends on the patient’s expectations, Queler said. “The patients need to understand that [with fusion] they’re not going to have any motion there. Some patients are not OK with that.”

Although no patients have undergone fusion, it is a reasonable option if the procedure fails. “Minimal bone is resected in capsular interposition arthroplasty and therefore, a fusion can be done later without the need for a structural bone graft,” Queler said.

He said capsular interposition arthroplasty is not recommended for patients younger than 50 years old or those patients who have a short first metatarsal or those with metatarsalgia.

At 1-year postoperatively, this patient is showing good healing of the medial incision at the first metatarsophalangeal joint after capsular arthroplasty.

Demonstration of dorsiflexion
This patient is demonstrating dorsiflexion of the great toe at 1 year after undergoing capsular arthroplasty of the first metatarsophalangeal joint for hallux rigidus.

Demonstration of plantarflexion
This patient is demonstrating plantarflexion in the great toe at 1 year after capsular arthroplasty in the first metatarsophalangeal joint.

For more information:
Chao W, Parekh S, Queler SR, et al. Capsular interposition arthroplasty for hallux rigidus: A retrospective analysis. Presented at the American Orthopaedic Foot and Ankle Society 22nd Annual Summer Meeting. July 14-16, 2006. La Jolla, Calif.
Hamilton W, O’Malley M, Thompson F, et al. Capsular interposition arthroplasty for severe hallux rigidus. Foot Ankle Int. 1997;18:68-70.
Seth Robert Queler, MD, can be contacted at 120 Mineola Blvd., suite 600, Mineola, NY 11501, 516-747-8900, or www.winthroporthopaedics.com/.