Radiodensity Analysis of Medial Column Superconstruct Fixation Sites in Midfoot Charcot Neuroarthropathy

Midfoot beam-plate constructs for Charcot neuroarthropathy: A Cohort study with midterm follow-up

The technique of intramedullary beaming of the metatarsals with a supplemental medial locking plate is an emerging technique to achieve and maintain plantigrade, ulcer-free feet in patients with Charcot neuroarthropathy. A retrospective chart review was performed to evaluate radiographic and clinical outcomes for 40 patients (41 limbs) with Charcot neuroarthropathy after operative management with medial beam-plate constructs between January 2014 and October 2023. Lateral Meary's angle was measured pre- and postoperatively to serve as a proxy for surgical correction of midfoot Charcot deformity. The mean age of the cohort was 57.6 (range, 37-73) years and 43.9 % (18/41) had an ulcer present at time of surgery. Mean clinical follow-up was 29.1 (range, 4-80) months. 94.4 % (17/18) of ulcers present at the time of surgery healed. Seven (17.1 %) patients in our cohort underwent a major amputation. The amputation rate after adopting the medial beam-plate construct approach decreased by 26 % compared with our institutional baseline data of patients treated with other techniques. Preoperative lateral Meary's angle averaged -31.0 degrees, immediate postoperative measured -5.3 degrees (p < 0.001), and final postoperative was -14.4 degrees (p < 0.001). Patients undergoing medial beam-plate constructs had a relatively low rate (17.1 % [7/41]) of major amputation, and a large portion of the remaining patients (82.4 %[28/34]) achieved a plantigrade, shoeable, ulcer-free foot at final follow-up. Active ulceration may not be a contraindication to open reconstructive surgery. Furthermore, medial beam-plate construct demonstrated radiographic maintenance of deformity at final follow-up.

Association Between Pronation External Rotation IV Fracture Pattern and Regional Bone Density

INTRODUCTION

Throughout the musculoskeletal system, fracture patterns and subsequent healing rely partly on bone density. In the foot and ankle, bone density has been shown to play a role in supination and external rotation fracture patterns. Adding to previous research, this investigation examines the association between bone density and trimalleolar versus trimalleolar equivalent fracture patterns following pronation and external rotation injuries using computed tomography (CT)-derived Hounsfield units (HU).

METHODS

A retrospective chart review was conducted among patients without a history of fracture or osteoporosis who sustained a PER IV fracture. Demographic data were collected. Fractures were separated between PER IV equivalent and fracture groups. CT-derived HU was assessed at the distal tibia and fibula. Density was compared between PER IV equivalent and fracture groups and among posterior malleolar fracture patterns.

RESULTS

Seventy-five patients met the selection criteria, with 17 comprising the equivalent group and 58 in the fracture group. There were 38 type 1, 9 type 2, and 11 type 3 posterior malleolus fractures. The ankle bone density of the PER fracture equivalent group (331.98 ± 65.71HU) was greater than the PER fracture group (281.61 ± 76.99HU; P = .008). A statistically significant difference in tibial bone densities among equivalent and all PER fracture types (P = .01) with the equivalent group (331.98 ± 65.71HU) maintaining a greater tibial bone density than the type 2 posterior malleolus fracture group (252.35 ± 57.33HU; P = .009).

CONCLUSION

Higher bone density was associated with PER IV equivalent fractures; however, there was no density difference among posterior malleolus fracture types. When presented with PER IV fractures, consider fixation that addresses a lower bone density.

LEVEL OF EVIDENCE

III.

Intraoperative Radiation Exposure During Midfoot Charcot Reconstruction

While radiation exposure in foot and ankle surgery varies by procedure, attempts to minimize this hazard remain imperative to protect patients and surgeons. Hindfoot deformity correction employs significant radiation through intraoperative fluoroscopy, however, a paucity of data exists concerning Charcot reconstruction. This investigation describes and compares radiation exposure across varying Charcot pathology and fixation constructs. A retrospective chart review of patients undergoing midfoot Charcot reconstruction under large C-arm assistance from 2016-2022 was conducted. Demographics, pathology-specific, and intervention-specific variables were recorded and compared among midfoot reconstructions. The threshold for statistical significance was set at p ≤ .05. Among 40 patients, the average midfoot radiation exposure and fluoroscopy times were 9.5 ± 5.39 mGy and 256.64 ± 130.67 seconds, respectively. There existed no statistically significant difference in radiation exposure (p = .32) or fluoroscopy times (p = .71) among the different midfoot constructs. There existed a statistically significant relationship between radiation exposure with weight (p = .01) body mass index (p = .03) and number of stages (p = .04). Similarly, a relationship existed between fluoroscopy time with weight (p = .02), body mass index (p = .03), and number of beams/screws (p = .003). Due to the complexity of Charcot reconstruction coupled with multiple robust types of fixation, surgeons must remain cognizant of fluoroscopy usage. Moreover, providers who routinely perform Charcot reconstruction should wear personal protective equipment to protect against radiation.

Radiodensity Analysis of Lateral Column Superconstruct Fixation Sites in Midfoot Charcot Neuroarthropathy

Lateral column deterioration and subsequent loss of function poses a challenge for limb preservation in patients with Charcot neuroarthropathy (CN). Application of "superconstructs" provides stability and clinical improvement to an often-ulcerated lateral foot. This study examines radiodensity in Hounsfield units (HU) to compare bone quality of lateral column fixation targets using computed tomography (CT) scans between patients with and without midfoot CN. A retrospective chart review identified control (nondiabetic, non-CN; n = 29) and midfoot CN (n = 21) groups. Patient demographics and medical history were collected. Two reviewers measured the mean HU of circular regions of interest centered on the fourth and fifth metatarsal heads as well as the anterior, middle, and posterior thirds of the calcaneus. Radiodensity was compared between groups, among calcaneal locations, Eichenholtz stages and Brodsky types. A p value ≤.05 was considered statistically significant. Age and body mass index were not significantly different between groups. The CN group exhibited greater HU than the control group at the metatarsal head and calcaneus (p < .001). The anterior calcaneus exhibited greater HU than the posterior calcaneus in the CN group (p = .02). The difference in HU was not statistically significant between Stages 0-1 and Stages 2-3 or midfoot Brodsky Types. Indirect bone density analysis revealed an increased density in CN compared to control patients with no significant difference between midfoot CN stages or types. The anterior calcaneus was the densest rearfoot bone among the CN patients, a result that may have implications in surgical fixation.