Study Analysis Finds Revision Risk Comparable for Total Ankle Replacement and Ankle Arthrodesis

A recent article in the Journal of Bone and Joint Surgery compared outcomes of total ankle replacement (TAR) and ankle arthrodesis (AA) for ankle osteoarthritis. Researchers compiled longitudinal claims data from the states of New York and California, each over a multi-year period. Specifically, they examined a primary outcome of revision and secondary outcomes of in-hospital complications and below-knee amputation. Overall, the team looked at 1,477 TARs and 1,468 AA procedures.

The authors found that patients that had TAR had fewer comorbidities and were less likely to belong to a minority population than those that had AA procedures. Initial crude analysis suggested that the TAR cohort had a lower risk of revision, in-hospital complications, and below-knee amputation. However, they also performed a propensity-score-matched analysis, which revealed less significant differences (revision risk for TAR 5.6 percent, AA 7.6 percent, p = 0.16). Older age did seem to be predictive of lower revision risk after TAR, but age did not predict revision after AA. Also, female patients less frequently underwent revision after AA, but sex did not predict revision after TAR. In total, the authors commented that the frequency of performed TAR procedures has caught up with that of AA procedures.

Jeffrey E. McAlister, DPM, FACFAS says that this large observational study highlights some of the consistencies that he sees in his daily practice.

“As the volume of ankle arthroplasty procedures are increasing, the sheer number of successful outcomes are going to improve,” he explains. “Ankle arthrodesis is becoming reserved for failed ankle arthroplasty or Charcot neuroarthropathy, which inherently is going to have a higher revision rate.”

Jason DeVries, DPM, FACFAS points out that the revision rates in this article are lower than several historical articles, but are in line with modern research and his own experience.

“I also agree that ankle arthrodesis has a higher rate of revision and complications,” he says. The crude analysis presented shows that there is a rate of revision that is higher in AA and may reflect a higher-risk patient population. Even in the propensity matched comparison, though, the rate of revision is still higher in AA, although no longer statistically significant.”

This study holds value not just for surgeons, but for hospitals, says Dr. McAlister, in practice in Phoenix and Scottsdale, AZ.

“We are continuing to see growth in foot and ankle procedures, and as we move forward with cost containment, all parties included want to see improved outcomes,” he says. “To see consistent data supporting both ankle fusion and arthroplasty is great, below 10 percent for two complicated foot and ankle cases.”

Dr. DeVries, in practice in Manitowoc, WI, agrees, adding that this paper helps surgeons to understand current trends in patient selection and outcomes.

“The historical recommendation for TAR in older, less demanding (candidates) is not the current standard, and patients can still have excellent outcomes,” he says. “In addition, the historical understanding that AA is performed far more commonly that TAR is not backed up with the article. Roughly even numbers of AA and TAR took place, and that is representative of my practice as well.”

Overall, Dr. McAlister feels that, in part due to the findings of this study, today’s foot and ankle surgeons can start to have more confident conversations with patients regarding outcomes and expectations. Dr. DeVries adds that the article represents a real-world study of current, state-of-the-art practices with respect to TAR and AA.

A Closer Look At Onychomycosis Prevalence Among Patients With Psoriasis

By Jennifer Spector, DPM, FACFAS, Managing Editor

A recently published study in Dermatologic Therapy looked at frequency and characteristics of onychomycosis in 81 patients with psoriasis, using 30 patients thought to have onychomycosis, but who did not have psoriasis, as a control. Researchers performed direct microscopy and fungal culture on nails suspicious for onychomycosis or psoriatic involvement. They also recorded clinical examination findings, psoriasis area and severity index (PASI) scores, nail psoriasis severity index (NAPSI) scores, body mass index (BMI) and laboratory data.

Fungal cultures came back positive for 23.5 percent of the psoriatic cohort. The authors found the highest rates of onychomycosis in patients undergoing conventional or biologic therapy. The authors identified higher rates of onychomycosis in patients receiving biologic or conventional therapies, with multiple organisms present among the samples, including non-dermatophyte molds. Onychomycosis did not exhibit any statistically significant relationship with the PASI, NAPSI score, or BMI.

They found psoriatic nail involvement most prevalent in those not receiving formal treatment (68.8 percent), following by those using biologic agents or topicals (31.3 percent each). Patients with psoriasis receiving conventional therapies exhibited a 5.9 percent incidence of nail involvement. The difference between the patients who did not receive treatment and those who received conventional treatment was significant (p < 0.05).

The authors conclude that nail changes in patients with psoriasis receiving biologic or conventional therapy would benefit from dual, detailed evaluation both locally and through culture.

When a patient with nail pathology has psoriasis, Nicole M. DeLauro, DPM, FACPM, DABFAS, says she definitely prefers a biopsy to determine if mycosis is also present, including high-sensitivity testing of periodic acid Schiff (PAS), Grocott methenamine silver stain (GMS), Fontana-Masson stain (FM), and polymerase chain reaction (PCR).

“Patients with psoriasis receiving therapies can have an increased prevalence of onychomycosis,” she says. “If nail changes are noted on clinical exam, there should be a high suspicion of onychomycosis and further examination is warranted”

Dr. DeLauro, who practices in New Jersey and New York, stresses that clinicians can see nail dystrophy associated with systemic diseases and that these findings can serve as an early diagnostic tool for the everyday practicing podiatrist.

Which Radiographic Measurement Method is Best for Metatarsus Adductus?

By Jennifer Spector, DPM, FACFAS, Managing Editor

A recent study in the Journal of Clinical Medicine favored the Sgarlato and modified Sgarlato techniques for radiographic measurement of metatarsus adductus (MA). The researchers examined 80 weight-bearing dorsoplantar X-rays, all from recreational football (soccer) players in Spain. The subjects were all over the age of 21 and practiced their sport more than 5 hours each week. Each cohort had 40 feet, and an equal distribution of men and women (divided into control and metatarsus adductus groups). They matched controls according to age and gender. Specifically, they examined the following methods of measurement of metatarsus adductus: Sgarlato, modified Sgarlato, Rearfoot, Root, Engel, modified Engel, Kite, Kilmartin, modified Kilmartin, Simons, and Laaveg and Ponseti.

The authors found excellent reliability (p > 0.900) for the Sgarlato and modified Sgarlato methods. They also found a low standard error of measurement (SEM), coefficient of variation (CV), and minimum detectable change (MCD) for these two methods of measurement. The remaining measurement methods reveal intra- or inter-rater reliability with intraclass correlation coefficient (ICC) < 0.900, systematic differences between intersession or interobservers, or high MCD value.

In the article, the authors say that no previous publications evaluate all of the currently available methods to measure metatarsus adductus deformity. They additionally point out the clinical challenge of a lack of agreement on landmarks used to document and chart these angular measurements. Assessing reliability and repeatability, such as in this study, could be important in helping clinicians perform efficient and complete assessment of this condition, they contend.