Anterior Ankle Incision Wound Complications Between Total Ankle Replacement and Ankle Arthrodesis: A Matched Cohort Study.

The anterior incision is commonly used for total ankle replacement (TAR) and ankle arthrodesis. Historically, the anterior incision has demonstrated a high incidence of complications. The purpose of this study was to evaluate anterior incisional healing and soft tissue complications between TAR and ankle arthrodesis with anterior plate fixation.This was an IRB-approved retrospective review of wound healing and other complications among 304 patients who underwent primary TAR (191 patients) or ankle arthrodesis (113 patients) via the anterior approach over a 4-year period. The operative approach, intraoperative soft tissue handling, and postoperative protocol for the first 30 days were the same between groups. The mean follow-up was 11.8 months. To diminish the effect of selection bias, a subgroup analysis was performed comparing 91 TAR patients matched to an equal number of demographically similar ankle arthrodesis patients. Overall, 19.7% of patients experienced delayed wound healing greater than 30 days. Although the TAR and arthrodesis subgroups had dissimilar demographics, there was no difference in outcomes. Between matched pairs, no statistically significant differences were observed; however, trends were identified with matched cohort groups when compared to the overall patient series. These trends toward statistically significant differences in delayed wound healing and incidence of wound care in the matched cohort groups warrants further investigation in larger series or multicenter study. Further work is needed to identify the modifiable risk factors associated with the anterior ankle incision.

Medial Structure Injury During Suture Button Insertion Using the Center-Center Technique for Syndesmotic Stabilization.

BACKGROUND: The center-center technique for syndesmosis fixation has been described as an improved and reliable technique for proper reduction of the syndesmosis during ankle fracture repair. Concurrently, the use of flexible fixation with a suture button is becoming an established means of syndesmosis stabilization. The purpose of this cadaveric study was to assess for medial structure injury during the placement of a suture button using the center-center technique for ankle syndesmosis repair at 3 insertion intervals. METHODS: Simulated open syndesmosis repair was performed on 10 cadaveric specimens. Three intervals were measured at 10 mm, 20 mm, and 30 mm proximal to the level of the distal tibial articular surface along the fibula. Proper longitudinal alignment of the center-center technique was completed under fluoroscopic guidance and was marked on the medial aspect of the tibia. The 3 intervals were drilled in the appropriate technique trajectory. The suture button was subsequently passed through each drill-hole interval. A single observer used a digital caliper to measure the distance from each suture button aperture with respect to the tibialis anterior tendon, tibialis posterior tendon, and greater saphenous vein and nerve. RESULTS: A total of 30 interval measurements (10 cadavers with 3 suture button segments each) were used for data analysis. Direct impingement on the greater saphenous vein was seen in 11 of 30 (36.6%) interval measurements. Six of the 11 (54.5%) observed saphenous structure impingement events occurred at the 10-mm drill hole. CONCLUSION: The results of the present study suggest that the use of the center-center technique for syndesmosis repair with suture button fixation risks preventable injury to the greater saphenous neurovasculature. CLINICAL RELEVANCE: To understand the medial ankle anatomy, as it pertains to insertion of flexible syndesmotic fixation in a cadaveric model, to aid in prevention of clinical iatrogenic injury.

Arthroscopic Evaluation of Syndesmotic Instability and Malreduction.

Ankle fractures are a common injury treated by orthopaedic surgeons. The distal tibiofibular syndesmosis can be injured during these fractures as well as in isolation. They pose a significant challenge with regard to the diagnosis of instability as well as evaluating reduction after fixation. Multiple studies have demonstrated that traditional radiographic analysis fails to accurately identify syndesmotic diastasis, instability, or malreduction. Ankle arthroscopy has been proposed as an alternative way to evaluate the syndesmosis. Ten transtibial amputation cadavers were utilized for this study. Two distinct analyses were undertaken. The first, analysis of instability, utilized 2 dissection groups, a superficial dissection only and a partial disruption instability model. The second analysis was of syndesmotic malreduction. For this, all 10 specimens underwent complete disruption of the syndesmosis and subsequent fixation in either anatomic alignment or malreduction. Both analyses were performed by surgeons blinded to the condition of the syndesmosis. Two groups of surgeons were able to identify syndesmotic instability a combined 75% of the time. Malreduction diagnosis was mixed with a 100% accurate diagnosis of sagittal plane displacement but only 50% accuracy for rotation and 17% for an anatomic reduction. Syndesmotic injury during ankle fracture presents a significant problem to the treating surgeon. Ankle arthroscopy has been shown in the literature to be highly sensitive for diagnosing instability but has not been evaluated in diagnosing malreduction. The current study shows moderate success in diagnosing both malreduction and instability. LEVELS OF EVIDENCE: Therapeutic, Level V: Basic Science.

Clinical Adaptation of the "Tibiofibular Line" for Intraoperative Evaluation of Open Syndesmosis Reduction Accuracy: A Cadaveric Study.

BACKGROUND: The "tibiofibular line" is a new axial computed tomography parameter for assessing syndesmosis reduction, which references the flat anterolateral surface of the fibula and anterolateral tibial tubercle. These same bony landmarks are easily visualized via a lateral approach to the fibula. This cadaveric study assessed the practical aspects of measuring the tibiofibular line intraoperatively. METHODS: Three observers simulated the tibiofibular line using operative rulers in 3 measurement series utilizing 10 cadaveric specimens: intact syndesmosis, syndesmosis reduction, and fixation after application of lateral plate and screws to the fibula, and post syndesmosis reduction and fixation without plate and screws. RESULTS: The majority (78%) of clinical tibiofibular line measurements were within the "normal" range (0-2 mm). However, there was a general trend toward malreduction (>2 mm) across measurement series. Intraobserver variability ranged from poor to excellent (intraclass correlation range, 0.12-0.85, Fleiss kappa range, 0.19-0.40) and interobserver reliability was only generally in the fair range (intraclass correlation range, 0.49-0.61; Fleiss kappa range, 0.19-0.40). CONCLUSION: Taken as a whole, these findings found that the technique was feasible but clearly indicated that further refinement of this protocol, including the use of computed tomography, would be needed to determine if better control of confounding variables would reveal better observer reliability. CLINICAL RELEVANCE: The CT-based TFL technique for syndesmosis reduction assessment could not reliably be translated into an intraoperative open technique because of the confounding effects of subjectivity and operator error.

Obtaining Volar Tilt in Distal Radius Fixation: Use of a Screw as a Proximal Post.

Volar plating of distal radius fractures was introduced as a means to circumvent some of the issues with dorsal-based plating but has been shown not to be a complete panacea, as other advantages and challenges have subsequently been discovered. Careful attention and proper technique must be utilized to restore and maintain volar tilt. This study reports a technique of using a locking screw as a proximal peg to reliably obtain the volar tilt in a simple fashion.

Effect on Clinical Outcome and Growth Factor Synthesis With Adjunctive Use of Pulsed Electromagnetic Fields for Fifth Metatarsal Nonunion Fracture: A Double-Blind Randomized Study.

BACKGROUND: Electromagnetic bone growth stimulators have been found to biologically enhance the bone healing environment, with upregulation of numerous growth factors. The purpose of the study was to quantify the effect, in vivo, of pulsed electromagnetic fields (PEMFs) on growth factor expression and healing time in fifth metatarsal nonunions. METHODS: This was a prospective, randomized, double-blind trial of patients, cared for by 2 fellowship-trained orthopedic foot and ankle surgeons. Inclusion criteria consisted of patients between 18 and 75 years old who had been diagnosed with a fifth metatarsal delayed or nonunion, with no progressive signs of healing for a minimum of 3 months. Eight patients met inclusion criteria and were randomized to receive either an active stimulation or placebo PEMF device. Each patient then underwent an open biopsy of the fracture site and was fitted with the appropriate PEMF device. The biopsy was analyzed for messenger-ribonucleic acid (mRNA) levels using quantitative competitive reverse transcription polymerase chain reaction (QT-RT-PCR). Three weeks later, the patient underwent repeat biopsy and open reduction and internal fixation of the nonunion site. The patients were followed at 2- to 4-week intervals with serial radiographs and were graded by the number of cortices of healing. RESULTS: All fractures healed, with an average time to complete radiographic union of 14.7 weeks and 8.9 weeks for the inactive and active PEMF groups, respectively. A significant increase in placental growth factor (PIGF) level was found after active PEMF treatment (P = .043). Other factors trended higher following active PEMF including brain-derived neurotrophic factor (BDNF), bone morphogenetic protein (BMP) -7, and BMP-5. CONCLUSION: The adjunctive use of PEMF for fifth metatarsal fracture nonunions produced a significant increase in local placental growth factor. PEMF also produced trends toward higher levels of multiple other factors and faster average time to radiographic union compared to unstimulated controls. LEVEL OF EVIDENCE: Level I, prospective randomized trial.

Arthroscopic Evaluation of Syndesmotic Instability in a Cadaveric Model.

BACKGROUND: Ankle fractures are among the most common lower extremity injuries. Proper care requires evaluation for syndesmotic ligament disruption. Ankle arthroscopy has been proposed as an intraoperative tool that can evaluate stability. Our focus was to evaluate the amount of displacement produced in the coronal, sagittal, and transverse planes visualized through ankle arthroscopy in a cadaveric model. METHODS: Seven below-knee specimens were mounted in a traction tower. Four groups were evaluated: no ligamentous disruption; anterior inferior tibiofibular ligament and interosseous ligament disruption; above plus anterior talofibular ligament and calcaneofibular ligament disruption; and posterior inferior tibiofibular ligament and transverse ligament disruption. Force was applied and measured using a digital scale. The amount of displacement of the fibula in relation to the center of the incisura was measured under arthroscopic evaluation using a calibrated probe. RESULTS: An intact syndesmosis and lateral ankle ligaments provided multiplanar stability. In group 2, syndesmosis diastasis was appreciated in the transverse-external rotation plane with as little as 6 lb of force. In group 3, a greater amount of displacement was appreciated with less force. Multiplane instability was visible in every specimen with as little as 2 lb of force. Group 4 specimens were completely disrupted and so grossly unstable that testing was impossible. CONCLUSION: Ankle arthroscopy has the potential to evaluate even partial disruption of the syndesmotic ligament complex. Instability in the sagittal and transverse planes was encountered early in the spectrum of disruption. Traditional evaluation methods have poor sensitivity for instability in these planes. CLINICAL RELEVANCE: Arthroscopic evaluation of subtle displacement in multiple planes may assist the surgeon in understanding the extent of the syndesmotic injury. Further studies are necessary to determine to what extent instability requires fixation as well as the role for arthroscopy in assessing anatomic reduction of the syndesmosis after fixation is performed.