Percutaneous and minimally invasive techniques for the treatment of calcaneal fractures are becoming more popular. In their study, Tomesen et al. report on their use of the modified method of Forgon and Zadravecz1 on patients over an eight-year period. This retrospective review of thirty-seven patients suggests that this technique can be successful but that it has limitations.
In any series of patients involving fracture treatment, it is important to understand the fracture population. In this report, the large majority of fractures (thirty-two of thirty-seven) occurred as a result of a fall from a height, representing a “lower-energy” mechanism of injury. This technique may not be applicable in centers that treat patients with motor-vehicle and other high-energy trauma. On the average, fractures were surgically treated eight days after injury, with a range of one to seventeen days. The timing of surgery is consistent with many expert opinions that percutaneous techniques need to be performed early, when the fracture fragments are relatively easy to manipulate because the reduction technique relies on ligamentotaxis2. The authors treated 123 calcaneal fractures during the time period of the study, but only sixty-nine fractures were treated with this technique, of which forty-seven met inclusion criteria and ten were lost to follow-up. Although the authors utilized multiple classification systems, they stated that adequately sized sustentaculum and tuberosity fragments to support screw fixation were the key criteria used in selecting this technique.
The study outcome measures included radiographic assessment, the American Orthopaedic Foot & Ankle Society (AOFAS) score, the Maryland Foot Score (MFS), and the Short Form-36 (SF-36), as well as functional assessments. Anatomically, their method successfully restored calcaneal height and partially restored calcaneal width and Böhler angle (average, 20.1°). Range of motion was 78% of normal in the sagittal ankle plane and 55% of normal through the subtalar joint. AOFAS, MFS, and SF-36 scores were uniformly improved in most patients, with no significant difference detected among different fracture classifications with the number of patients available in the study. The only significant difference was a substantial increase in the need for footwear modification in patients who had a Sanders type-IV calcaneal fracture. Restoration of the Böhler angle did not correlate with functional outcome, nor did fracture type. Most patients (70%) returned to their previous level of work, but it is not clear how strenuous the work environments were. Just 57% were able to return to previous levels of physical activity. Most concerning was an infection rate of 13%, which is not an improvement over the results of many of the studies cited in the Discussion section of their paper. Three of these five infections were deep, which is concerning in a technique designed, in part, to minimize wound and infectious complications. In addition, there was very high rate of screw removal (46%), which, while not a failure of treatment, does obligate the patient to a second procedure.
Calcaneal fractures are severe injuries that are challenging to treat. Tomesen et al. present us with a technique that works well in their hands but is not necessarily superior to other described and reported minimally invasive and open techniques. The strengths of this study lie in the standardized technique, the heterogeneous fracture population, the multiple outcome measures, and the two-year follow-up. These strengths are tempered by limited numbers, the fact that more than 20% of patients were lost to follow-up, and the lack of postoperative computed tomography scans to assess the ability of this technique to restore articular congruity. The surgeon treating these injuries requires multiple techniques to address different fracture scenarios. Some authors have suggested that these techniques should be reserved for less comminuted fractures3 and the authors appear to agree without clear support from their data in this retrospective review. Considering the severe soft-tissue injuries that accompany calcaneal fractures and the fact that minimally invasive methods allow earlier intervention without an increased prevalence of wound problems, these techniques are here to stay. A recent review of calcaneal fracture treatment4 highlighted the fact that we currently lack well-designed studies comparing minimally invasive and open procedures for similar fracture patterns. Those investigations are the logical next step for these and other researchers in this field.
This study and other similar studies that were mentioned in the Discussion section illustrate that respect for the soft tissues and achievement of the best possible fracture reduction are the key elements of treatment. The authors do not use this method exclusively, which stresses the point that the ability to perform these minimally invasive techniques comes from experience in treating these fractures with an open technique. A thorough understanding of the complex anatomy of the calcaneus and its articulations is crucial if one plans to attempt minimally invasive treatments for these calcaneal fractures.