True innovation—improvement way beyond the incremental—is rare in orthopaedics, whether it’s pre- and postoperative management, surgical technique, or prosthetic design. Innovation is even rarer, understandably, in addressing conditions that themselves are rare. Rarer still are innovations in treating pediatric conditions because of the many different congenital etiologies that don’t present in sufficient numbers to meaningfully study interventions.
Congenital pseudarthrosis of the tibia is one such rare pediatric condition, and it is one of the most challenging problems facing pediatric orthopaedic surgeons. In its pre-fracture state, this condition is called congenital tibial dysplasia or anterolateral bowing of the tibia. The goal of treatment at this stage is preventing fracture in the dysplastic, bowed area, because post-fracture union is difficult to achieve and maintain—and because chronic nonunion puts patients at risk for long-term pain, deformity, and disability.
In the December 2, 2020 issue of The Journal, Laine et al. present results of a simple outpatient surgical solution to this problem in 10 pediatric patients who were followed for an average of 5 years. Using a limited-exposure, plate-and-screw approach to control physeal growth, these authors produced correction in tibial alignment in all 10 patients. Most importantly, no patient developed a tibial fracture or pseudarthrosis after the guided-growth procedure, which also improved radiographic appearance of dysplastic bone and preserved leg length. Although 6 of the 10 patients required a plate exchange, the authors’ institution now offers this procedure as first-line treatment to all patients presenting with pre-fracture congenital tibial dysplasia.
Congenital bowing of the tibia is a condition that will probably never be subject to a controlled clinical trial due to the (fortunately) low number of patients affected. However, carefully conducted small cohort studies such as this can reveal true innovation that advances care for small but very vulnerable populations.
Marc Swiontkowski, MD
There has been a huge worldwide effort over the last 2-plus decades to establish arthroplasty registries. Among the many advantages of such registries, advocates emphasize the potential detection of early failures associated with new implant designs and biomaterials. The large number of patients enrolled in most registries and the methodical capturing of data yield substantial statistical and research benefits.
Based on the successes of arthroplasty registries, parallel registries have been established for sports medicine (especially for shoulder and knee conditions and treatments), fractures, musculoskeletal tumors, and others. Although the focus has been on enrolling large numbers of patients with relatively common disorders or procedures, there have been less well-publicized efforts to create smaller registries of rarer diseases.
In the October 21, 2020 issue of The Journal, Forman et al. use the 8-site Congenital Upper Limb Differences (CoULD) registry to report on associations between congenital deficiency of the radial aspect of the forearm in 259 patients (383 involved limbs) and thumb hypoplasia. Two findings stood out to me:
- The severity of radial deficiency was correlated with the severity of thumb deficiency.
- Compared with subjects who had no diagnosed syndromes, patients with concomitant syndromes (such as VACTERL and Holt-Oram) were twice as likely to have bilateral deficiency and 2.5 times as likely to have radial and thumb deficiencies as opposed to thumb deficiency alone.
In addition to reinforcing findings from previous single-institution studies, these data from Forman et al. will help surgeons counsel parents, determine treatment approaches, and establish frameworks for following patient outcomes after both surgical and nonsurgical treatment. It is my hope that other clinician-researchers with interest in understanding and managing rare conditions will establish similar registries to benefit these smaller but no-less-important groups of patients and families.
Click here to read the JBJS Clinical Summary on Congenital Hand Differences.
Marc Swiontkowski, MD