Diagnosis, technique may affect proximal interphalangeal joint replacement failure rates

Extensor mechanism failure was associated with more than two-thirds of re-operations following non-constrained interphalangeal proximal joint arthroplasty, according to results of a large retrospective study presented at the 2011 Annual Meeting of the American Society for Surgery of the Hand.

“Extensor mechanism pathology was the most common etiology in our series for re-operations following [proximal interphalangeal joint] PIPJ non-constrained arthroplasty, and these were associated with what we considered to be more aggressive dorsal approaches,” Tamir Pritsch, MD, a former Mayo Clinic fellow, and currently a hand surgeon in Tel Aviv Sourasky Medical Center, said.

In a study conducted from 2001 to 2009, Pritsch and senior author Marco Rizzo, MD, analyzed why re-operations occurred following unconstrained PIPJ arthroplasty in 76 fingers of 59 patients. The procedures involved 50 pyrocarbon and 26 metal/plastic implants. All but six implants were cemented.

They also examined the number of re-operations per finger, analyzing clinical outcomes using a univariate model.

Factors for replacement

The investigators studied 40 women and 19 men with a mean age of 51 years who had an average follow-up of 2.3 years. Overall, 21 index, 27 middle, 18 ring and 10 small fingers required surgery. Forty-five (59%) fingers underwent one operation, 19 fingers (25%) underwent two surgeries, 11 fingers (14.5%) underwent three surgeries and one finger (1.3%) underwent four operations, according to the abstract.

In 35 patients, primary osteoarthritis (OA) was the main diagnosis and indication for surgery. Post-traumatic OA led to surgery in 24 cases, and inflammatory arthritis was the diagnosis and cause for surgery in 17 cases.

The results showed that extensor mechanism dysfunction caused 67% of PIPJ arthroplasty failures, and Chamay or central slip reflection approaches were associated with the most failures in that group. Component loosening was the next most frequent cause of failure (22%).

Reasons for reoperation

Pritsch said that the initial diagnosis and surgical approach were associated with failures, noting the association between extensor mechanism failures and the chamay and central slip reflection approaches, and that 13% of the failures were for collateral ligament failure, with inflammatory arthritis being the primary cause of PIPJ disease. Significant associations between increased number of reoperations and amputations and arthrodeses were found.

“It is important to emphasize we are not saying in any way that non-constrained PIPJ arthroplasties should not be used,” Pritsch told Orthopedics Today. “The purpose of the paper was to identify reasons for failures in order to hopefully improve future outcomes.”

Overall, there was an average of 1.6 re-operations. On average, women had 1.7 reoperations and men had 1.4 reoperations. Collateral ligament failure was associated with two reoperations on average, while the reoperation rate was 1.5 in cases without collateral ligament failure.

The researchers found no significant difference between preoperative and postoperative range of motion and reported that most patients reported mild or no pain at follow-up. – by Jeff Craven

Reference:

• Pritsch T, Kakar S, Rizzo M. Reoperations following proximal interphalangeal joint unconstrained arthroplasty. Paper #49. Presented at the 2011 Annual Meeting of the American Society for Surgery of the Hand. Sept. 8-10. Las Vegas.

• Tamir Pritsch, MD, can be reached at the Division of Hand Surgery, Orthopedic Department, Tel Aviv Sourasky Medical Center, 6 Weizmann St., Tel Aviv, Israel; email: pritscht@gmail.com.
• Marco Rizzo, MD, can be reached at the Division of Hand Surgery, Orthopedic Department, Mayo Clinic, 200 1st Street, Rochester, MN; email: rizzo.marco@mayo.edu
• Disclosure: Pritsch, Kakar and Rizzo have no financial disclosures.

Re-operation following unconstrained proximal interphalangeal (PIP) joint arthroplasty remains a clinical problem. In this single institution, multi-surgeon cohort, one in four patients required re-operation and the most common reason was dysfunction of the extensor mechanism.

The current choices for unconstrained arthroplasty of the PIP joint are biomechanically sound devices; however, their efficacies are limited by the surgical approaches available to an anatomically complex joint. The success of unconstrained PIP joint arthroplasty hinges on management of the soft tissues. Failure of these devices is almost assured if the collateral ligaments, extensor mechanism or the volar plate are compromised during the surgical procedure.

Alternatives to current surgical approached to the PIP joint should be considered in order to improve the survival of the unconstrained arthroplasty of the PIP joint.

— Peter M. Murray, MD
College of Medicine, Mayo Clinic
Jacksonville, Fla.
Disclosure: Murray has no relevant financial disclosures.