Is Total Ankle Replacement Appropriate In Cases Of Severe Coronal Deformity?

Although preoperative coronal deformity greater than 20 degrees has historically been a contraindication for total ankle replacement (TAR), a recent study in the Journal of Bone and Joint Surgery contends that this is not necessarily true.

The study authors assessed 148 ankles after TAR and noted that 41 ankles had severe coronal deformity over 20 degrees. Employing radiographic and clinical evaluation, the authors compared outcomes between severe and moderate deformity groups. After a mean of 74 months follow-up, there was no significant difference in pain scores, disability scores, range of motion or complication rates between those with severe and moderate deformities. Postoperative tibiotalar angle and talar tilt angle were greater in the severe deformity group.

Ryan McMillen, DPM, FACFAS relates that he tries to perform TAR on congruent ankle joints, pointing out that implant survivorship is not the only consideration. 

“It’s also about edge loading and how it develops in joints with at least 10 degrees of coronal deformity,” explains Dr. McMillen, a member of the faculty for the Western Pennsylvania Hospital Foot and Ankle Residency Program in Pittsburgh. “This can lead to a need for poly exchange or abnormal wear on the implant.”

Mark Prissel, DPM, FACFAS, shares that large valgus deformities are more challenging and may require a staged approach, especially if they are associated with a flatfoot deformity and/or deltoid insufficiency.

Dr. McMillen agrees that ligamentous balancing may be required with these larger deformities and notes that he has seen no increase in complications in the short and intermediate terms with this balancing.

While this study showed similar results among the cohorts studied, Dr. Prissel says this may not be true in lower volume centers. 

“Complex TAR with large angular deformity should be performed by experienced TAR surgeons at centers of high volume,” maintains Dr. Prissel, who is in private practice with multiple locations in Ohio.

Dr. McMillen adds that a comparison to patients with low to no coronal deformity would have been interesting to see with this study. He acknowledges that this study could cause him to more closely consider a patient for TAR who has more than 10 degrees of deformity and is otherwise a strong candidate for the procedure. 

Study Says Younger And Less Active Patients More Prone To Sever's Disease

A recent study in the Journal of the American Podiatric Medical Association found that younger (mean age 9.8 years) and less active (sports sessions less than 60 minutes) patients are more likely to suffer from calcaneal apophysitis. 

The study included 430 children (328 male, 102 female) aged six to 14 years old. Most of the children participated in sports a mean of 2.8 times per week with each session being 60 to 120 minutes for most respondents. In addition to the primary findings regarding age and activity level, the study authors did not identify any significant differences with regard to sex, foot posture, BMI, terrain type or type of sport.

Stephen Kominsky, DPM, FACFAS says a keen understanding of the biomechanics of Sever’s disease is key to successful outcomes. Maggie Fournier, DPM, FACFAS echoes the importance of biomechanics. 

When asked about the typical patient profile in their practices with calcaneal apophysitis, both doctors have had similar clinical experiences seeing males around 11 years old in high-impact or running sports. However, age, gender and activity level may vary.

Dr. Kominsky shares that this study will not change his current patient treatment protocols. 

“I believe that treatment should be broken down into activity modification, mechanical support … and non-steroidal anti-inflammatory drugs (NSAIDs),” notes Dr. Kominsky, the former Director of Podiatric Medical Education at the Washington Hospital Center in Washington, DC. “Then, based on availability, things like physical therapy, laser and stretching/yoga can be of additional benefit.”

Relating that this study reinforces her current protocol for Sever’s disease, Dr. Fournier explains that a thorough history and sound physical examination should lead to a correct diagnosis without the need for additional imaging (unless there is concern of additional or different diagnoses).

“I do not hesitate to utilize ancillary services such as those provided by athletic trainers or physical therapists,” notes Dr. Fournier, the Immediate Past President of the American Academy of Podiatric Sports Medicine. “(Calcaneal apophysitis) can be a lingering and frustrating issue due to varying responses to treatment and continued sports demands on the patient.  However, we should not hesitate to modify our treatment plans to provide the most effective care.”

Study Looks At Umbilical Tissue In DFUs With Osteomyelitis

Could cryopreserved umbilical cord be an emerging option for complex, non-healing DFUs with osteomyelitis? A recent study in Wound Repair and Regeneration evaluated the use of such tissue (TTAX01) for these complex cases. 

Over a 16-week trial involving 32 patients with DFUs and underlying osteomyelitis, researchers performed initial surgical debridement and then the patients had a combination of systemic antibiotics with application of TTAX01. Patients received repeat applications of TTAX01 at no less than four-week intervals. The authors reported no major amputations and noted a 91 percent mean wound area reduction from baseline. 

Eric Leonheart, DPM relates treating countless DFUs and osteomyelitis over 25 years in practice. Although he has not used umbilical cord biologics, Dr. Leonheart shares he would only use biologic graft materials in complex wounds (exposed tendon, muscle, joint and bone) that are osteomyelitis-free. 

Stephanie Wu, DPM, MSc, FACFAS, a co-author of the study, says most advanced biologics are not indicated for complex, deep wounds with osteomyelitis. 

“It is rare to see a trial that focuses on complicated, deep, diabetic foot ulcers that extend to muscle, capsule or bone with radiographic evidence of osteomyelitis. There is truly a need for research (such as this) to assess the efficacy of novel biologic treatments to improve and accelerate healing in these complex wounds,” says Dr. Wu, the Associate Dean of Research, a Professor of Surgery at the Dr. William M. Scholl College of Podiatric Medicine and a Professor of Stem Cell and Regenerative Medicine at the School of Graduate Medical Sciences at the Rosalind Franklin University of Medicine and Science.  

Dr. Leonheart finds the study’s suggestion that TTAX01 may be a possibility for DFUs with osteomyelitis concerning, citing a lack of detailed information on infection staging, debridement and management along with a lack of control group.

“I am a firm believer in the principles of umbilical and placental biologics when it comes to augmenting compromised wound healing. However, I would not change my way of treating these complex infections based on the findings in this publication,” states Dr. Leonheart, who is affiliated with the Department of Orthopedics at Madigan Army Medical Center in Tacoma.

Dr. Wu states that it is important to note that this study is not a large-scale, randomized, controlled trial, and that one purpose of this study was to examine the operational aspects and ease of compliance with the study protocol before initiating a larger, phase 3 study. 

“We look forward to the confirmation of these findings in larger studies involving randomized comparison to other treatment strategies,” adds Dr. Wu.