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

Charcot neuroarthropathy (CN) is a highly destructive, pathologic process with devastating consequences to foot structure and viability. The use of intramedullary fixation “superconstructs” allows for “re-bar” support of compromised bone and allows for some dynamic fixation. This study examines radiodensity in Hounsfield units (HU) to compare bone quality of medial column fixation targets using computed tomography 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 a circular region of interest centered on the first metatarsal head and the anterior, middle, and posterior thirds of the talar body. Radiodensity was compared between groups, and among talar locations, Eichenholtz stages and Brodsky types, with statistical significance set at p ≤ .05. Age and body mass index were not significantly different between groups. The CN group maintained greater mean HU than the control group at the metatarsal head (p < .001), and talar body locations (p < .019). The difference in mean HU of these bones was not statistically significant between Stages 0 to 1 and Stages 2 to 3 or Brodsky Types 1 and 2. Mean HU differences among talus positions were not statistically significant. Indirect bone density analysis using HU showed an increased density in CN patients with no significant difference among talar body locations or midfoot Charcot stages and types. These results may assist in optimizing fixation length. Future studies may examine these densities in ankle CN.     

Early Results with Use of the Midfoot Fusion Bolt in Charcot Arthropathy

Charcot neuroarthropathy is a complicated condition affecting up to 1 in 680 diabetic patients that can rapidly cause severe destruction of the bony architecture in the foot, with resultant gross instability and frank deformity. Conservative care is not always successful at maintaining an intact soft tissue envelope of the foot; therefore, surgical reconstruction is often attempted in an effort to salvage the limb. The goal is to create a stable, plantigrade foot that can be placed in a shoe or simple brace. However, this effort is dramatically more challenging because of the pathologic bone biology, the inelasticity of the connective tissues, and the difficulty in maintaining non-weightbearing status during the postoperative period. Various forms of internal and external fixation have been described in published studies for use in this setting, all of which have been accompanied by complications such as nonunion, dehiscence, and implant failure. Although the concept of beaming the longitudinal columns of the foot is not new, it has previously been described with the use of cannulated screws. Cannulated screws are inherently weaker than solid-core screws and thus subject to failure at lesser loads. The midfoot fusion bolt offers a technical advantage compared with other forms of fixation in these challenging cases. We present our limited experience with 4 patients who had this device used as a part of the surgical approach and the short-term results. All patients went on to successful union of all fusion sites and were able to return to ambulation in diabetic shoe gear and appropriate bracing.     

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.     

A Systematic Review of Intramedullary Fixation in Midfoot Charcot Neuroarthropathy

Charcot neuroarthropathy can cause severe deformity of the midfoot, and intramedullary use of beams and bolts has been utilized as a method of definitive stabilization. This systematic review evaluated the outcomes of intramedullary beaming in patients with Charcot neuroarthropathy and determined the methodological quality of the studies. Four online databases were searched: PubMed, MEDLINE (Clarivate Analytics), CINAHL (Cumulative Index to Nursing and Allied Health) and Web of Science (Clarivate Analytics). To assess the methodological quality of the studies, the Coleman Methodology Score was used. The data was pooled into 2 outcomes groups for comparison: (1) Studies that reported on the outcomes of Charcot specific implants (study group). (2) Studies that reported on the outcomes using non-Charcot specific implants (control group). After screening, 16 studies were included. Compared to our control group, our study group had significantly higher rates of overall hardware complications, hardware migration, surgical site infection, reoperation, and nonunion. The study group had significantly lower rates of limb salvage compared to the control group. Our study and control groups did not differ in the rates of hardware breakage, wound healing complications, or mortality. The limb salvage rate was 92% and 97% of patients were still alive at a mean follow-up of 25 months. The mean Coleman Methodology Score indicated the quality of the studies was poor and consistent with methodologic limitations. The quality of published studies on intramedullary implants for Charcot reconstruction is low. Complications when utilizing intramedullary fixation for Charcot reconstruction are high, whether or not Charcot specific implants are used.     

Coronal Hindfoot Alignment in Midfoot Charcot Neuroarthropathy

Coronal plane hindfoot malalignment produces abnormal compensatory forces within the midfoot and forefoot. The primary aim of this study is to compare radiographic hindfoot alignment in patients with a midfoot Charcot event, and identify patterns associated with breakdown. A retrospective review of 43 patients (48 limbs) with midfoot Charcot neuroarthropathy were compared between the coronal hindfoot alignments and Charcot joint involvement. Coronal hindfoot alignment was classified as neutral (n = 15), valgus (n = 16), and varus (n = 17) utilizing the Saltzman hindfoot alignment radiograph. Charcot joint breakdown was classified as isolated tarsometatarsal joint (n = 8), combination of tarsometatarsal and naviculocuneiform joints (n = 22), and midtarsal joints including talonavicular and calcaneocuboid joints (n = 18). Patients exhibiting varus hindfoot alignment had 5.8 times greater risk of breakdown at the tarsometatarsal and naviculocuneiform joints (odds ratio 5.8, 95% confidence interval 1.7-22.9, p < .01). Hindfoot varus induces external rotation of the talus, resulting in compensation through the naviculocuneiform and tarsometatarsal joint, which correlates with our findings of a 6-fold increase in naviculocuneiform and tarsometatarsal joint collapse. Patients exhibiting valgus hindfoot alignment had 27 times greater risk of breakdown at the midtarsal joint (odds ratio 27.0; 95% confidence interval 5.6-207.0, p < .01). Hindfoot valgus induces internal rotation of the talonavicular joint, which correlates with our findings of a 27-fold increase in midtarsal joint breakdown. Varus and valgus hindfoot alignment are associated with different midfoot injury patterns, which may have implications in surgical management and allow for focused surveillance in neuropathic patients presenting with early-stage clinical findings consistent with Charcot neuroarthropathy.     

Beaming in Charcot Arthropathy—Intramedullary Fixation for Complicated Reconstructions: A Cadaveric Study

In the modern treatment of Charcot neuroarthropathy, beam screw fixation is an alternative to plate and screw fixation. Exposure is minimized for implantation, and this technique supports the longitudinal columns of the foot as a rigid load-sharing construct. A published data review identified a paucity of data regarding metatarsal intramedullary canal morphology relevant to beam screw fixation. The purpose of the present study was to describe metatarsal diaphyseal morphology qualitatively and quantitatively in an effort to provide data that can be used by surgeons when selecting axially based intramedullary fixation. Twenty fresh-frozen cadaveric below-the-knee specimens were obtained. The metatarsals were exposed, cleaned of soft tissue, and axially transected at the point of the narrowest external diameter. Next, a digital caliper was used to measure the size and shape of the diaphysis of the first through fourth metatarsals. The diaphyseal canal shape was categorized as round, oval, triangular, or pear. The widest distance between the endosteal cortical surfaces was measured. Triangular endosteal canals were only found in the first metatarsal, and the remainder of the metatarsal canals were largely round or oval. These data help to approximate the size of fixation needed to achieve maximal screw–endosteal purchase.     

Reliability of the Measurement of Cuboid Height in Midfoot Charcot Neuroarthropathy

Cuboid height is a quantitative radiographic measurement of the relationship of the inferior cuboid to the plantar osseous plane of the lateral column of the foot and might be associated with poor clinical outcomes in patients with midfoot Charcot neuroarthropathy. We evaluated the reliability of the cuboid height measured by a group of foot and ankle surgeons on subjects with midfoot Charcot neuroarthropathy. Ten board-certified foot and ankle surgeons, 10 residents, and 10 medical students measured the cuboid height on 11 lateral weightbearing radiographic projections of subjects with midfoot Charcot neuroarthropathy. Cuboid height measurements were grouped categorically with calculation of an intraclass correlation coefficient (ICC). Ten unique images were used, with 1 repeated image to provide a measure of intrarater agreement. The overall measure of reliability of cuboid height measurement was an ICC of 0.997. Specifically, the ICC was 0.987 for surgeons, 0.992 for residents, and 0.989 for students. Participants were in agreement with the repeated measure in 24 (80.0%) of 30 cases. Specifically, each group (surgeons, residents, and students) were each in agreement for 8 (80.0%) of 10 repeated measurements. In conclusion, these results demonstrate excellent reliability for radiographic measurement of cuboid height on subjects with midfoot Charcot neuroarthropathy. To the best of our knowledge, this is the first investigation to provide a measure of reliability for this radiographic outcome, which is potentially related to clinical outcomes in the evaluation and treatment of this challenging patient cohort.     

Midfoot and hindfoot arthrodeses in diabetic Charcot arthropathy.

OBJECTIVES: To review the clinical outcome of arthrodesis of the foot in patients with diabetic Charcot arthropathy and to review the pathophysiology, clinical and radiographic features of Charcot arthropathy. DESIGN: A retrospective review and clinical follow-up of a series of patients. SETTING: St. Michael's Hospital, Toronto, a tertiary care teaching hospital. PATIENTS: Ten diabetic patients treated between 1996 and 1998 who required an arthrodesis of the midfoot or hindfoot secondary to deformity of diabetic neuropathic joints. INTERVENTIONS: Three midfoot (Lisfranc) and 7 hindfoot arthrodeses with autogenous iliac-crest bone grafting and internal fixation. OUTCOME MEASURES: Patient satisfaction, maintenance of the correction of the deformity and avoidance of amputation. Western Ontario/McMaster University score and midfoot/hindfoot American Orthopaedic Foot and Ankle Society foot ratios. Clinical examination including E-MED pedographic examination. Correction and evidence of bony or fibrous union assessed radiologically. RESULTS: The postoperative correction was maintained, no further skin ulceration occurred and amputation was avoided in 9 of 10 patients. Because this is a salvage procedure and there was often significant concomitant illness, the results of clinical rating systems were poor. Five of 9 patients had clinical and radiographic evidence of a solid bony arthrodesis; 4 had a stable fibrous union. CONCLUSIONS: With careful surgical technique, a reasonable number of feet can be salvaged by an arthrodesis of a diabetic neuropathic joint when nonoperative measures fail. Patient selection is important because there is a significant complication rate.     

Two Cases of Periprosthetic Fracture After Surgery for Acute Midfoot Charcot

Charcot neuroarthropathy is a rare condition that often results in deformity of the foot and ankle, with a high incidence of ulceration and a high risk of amputation. Traditionally, treatment of the acute stages of Charcot foot has been nonoperative until consolidation. Still, a large number of patients develop deformities, and early operative treatment of unstable Charcot feet has been suggested. To overcome some of the inherent challenges when operating on acute-stage Charcot feet, the superconstruct technique has been proposed. Early surgery for dislocated Charcot foot is sparingly described in the literature. To investigate the utility of the superconstruct technique for acute midfoot Charcot, we planned a prospective cohort study including patients with midfoot manifestation (Brodsky 1) in the active stages of the disease. Patients eligible for the study were treated with open surgery and midfoot arthrodesis using the superconstruct technique. In this report, we present the development of periprosthetic fractures related to early surgery using the superconstruct technique, possibly causing a more proximal Charcot manifestation in 2 patients with >24 months of follow-up. To our knowledge, such complications have been sparsely noted in the literature.     

A Systematic Review of Current Surgical Interventions for Charcot Neuroarthropathy of the Midfoot

Charcot neuroarthropathy of the foot, or Charcot foot, is a pathologic entity of the foot, associated with diabetes mellitus. Owing to the increase of diabetes mellitus in developed nations worldwide, the prevalence of Charcot foot has been increasing. The initial treatment of Charcot foot is often conservative, with methods including bracing, casting, and the use of customized orthopedic shoes. However, many cases of Charcot foot eventually require surgery, because the consequent destabilization of the foot associated with bone, joint, and nerve injury due to the pathology eventually leave patients unable to walk independently. The present systematic review analyzed the published data regarding surgical interventions for midfoot Charcot deformities and estimated the rates of common complications occurring with the surgical modalities studied. The main outcomes of interest analyzed in the present study were postoperative amputation and bony fusion. The included cohort of patients with Charcot foot was very heterogeneous in terms of the demographic and comorbid characteristics. However, even with this heterogeneity, the present study should provide useful information to surgeons in terms of the outcomes after some of the common surgical procedures for midfoot Charcot.     

Relationship of Cuboid Height to Plantar Ulceration and Other Radiographic Parameters in Midfoot Charcot Neuroarthropathy

The objective of the present investigation was to examine the effect of cuboid height on the presence of plantar midfoot ulceration and the relationship of cuboid height to other commonly performed radiographic parameters during evaluation of midfoot Charcot neuroarthropathy. A retrospective analysis was performed of 68 feet in 60 subjects who met the inclusion criteria. We did not observe statistically significant differences in the presence of a plantar midfoot ulceration when considering a cuboid height threshold of 0.0 mm, 2.0 mm, ?2.0 mm, or ?5.0 mm nor was the cuboid height a robust predictor for the presence of plantar midfoot ulceration when considering the positive predictive value, negative predictive value, sensitivity, or specificity. We observed a significant negative association between a negative cuboid height and the presence of Sanders Type 2 deformities (76.2% of those with negative height versus 50.0% of those with positive height had type 2 deformities; p = .0036), the absence of radiographic visualization of the lateral tarsometatarsal joint (71.4% of those with negative height versus 26.9% of those with positive height had an absence of radiographic visualization; p = .005), and lower calcaneal inclination angles (6.06° versus 15.08°; p < .001). We further observed significant positive correlations between the cuboid height and the calcaneal–fifth metatarsal angle (0.655; p < .000), calcaneal inclination angle (0.591; p < .001), calcaneal–cuboid angle (0.254; p = .038), medial column height (0.264; p = .029), and first metatarsal inclination angle (0.245; p = .047). We also observed negative correlations with Meary's angle (?0.475; p < .001) and the talar declination angle (?0.387; p < .001). These findings showed a general trend toward a decreasing cuboid height and increasing sagittal plane deformity involving both the medial and the lateral columns. The results of the present investigation provide evidence against a single radiographic parameter being associated with the presence of plantar midfoot ulceration.     

Combined Medial Column Primary Arthrodesis,Middle Column Open Reduction Internal Fixation,and Lateral Column Pinning for Treatment of Lisfranc Fracture-Dislocation Injuries

Lisfranc fracture-dislocation can be a devastating injury with significant long-term sequelae, including degenerative joint disease, progressive arch collapse, and chronic pain that can be potentiated if not effectively treated. We present a case to demonstrate our preferred surgical approach, consisting of combined medial column primary arthrodesis, middle column open reduction internal fixation, and lateral column pinning, with the primary goal of minimizing common long-term complications associated with Lisfranc injuries. We present the case of a typical patient treated according to this combined surgical approach to highlight our patient selection criteria, rationale, surgical technique, and operative pearls. A 36-year-old male who had sustained a homolateral Lisfranc fracture-dislocation injury after falling from a height initially underwent fasciotomy for foot compartment syndrome. The subsequent repair 16 days later involved primary first tarsometatarsal joint fusion, open reduction internal fixation of the second and third tarsometatarsal joints, and temporary pinning of the fourth and fifth tarsometatarsal joints. He progressed well postoperatively, exhibiting an American College of Foot and Ankle Surgeons forefoot score of 90 of 100 at 1 year after surgery with no need for subsequent treatment. Lisfranc fracture-dislocations often exhibit primary dislocation to the medial column and are conducive to arthrodesis to stabilize the tarsometatarsal complex. The middle column frequently involves comminuted intra-articular fractures and will often benefit from less dissection required for open reduction internal fixation instead of primary fusion. We propose that this surgical approach is a viable alternative technique for primary treatment of Lisfranc fracture-dislocation injuries.     

Management of Complex Open Fracture Injuries of the Midfoot With External Fixation

Ten patients (11 feet) with severe, high-velocity, open injuries to the midfoot were treated with uniplanar external fixation. The mean patient age was 38 years. Five wounds measured >10 cm, and 3 had extensive degloving of the foot extending into the lower leg. All had grossly comminuted fractures of the tarsal and metatarsal bones: 9 patients had a fractured cuboid; 6 had a fractured navicular; 7 had a fractured cuneiform; and all had metatarsal fractures. Lisfranc joint dislocations were present in 7 feet, and intertarsal dislocations were seen in 3 cases. Six patients underwent split-thickness skin grafting, and 1 required a myocutaneous flap. The average duration of fixator use was 9 weeks (range, 6-15 weeks). Clinically, patients were evaluated 1 year after fixator removal for any residual pain in the foot, ability to stand on tiptoe, presence of a limp, deformity of an arch, and range of motion at the ankle, subtalar, and metatarsophalangeal joints. Each parameter was graded as good, fair, or poor. All patients had sensate plantigrade feet, with 2 patients who experienced pain on weight bearing, 5 who had difficulty standing comfortably on tiptoe, and 2 who limped because of pain. Three patients exhibited flatfoot deformity, whereas 4 had cavus deformity. All demonstrated stiffness at the midfoot and restriction of subtalar and forefoot motion, with 5 also having restricted ankle motion. Radiographically, all fractures were healed at the time of follow-up; 4 were malunited, with 1 demonstrating ankylosis across the tarsometatarsal joint. These results suggest that crush injuries to the midfoot often result in persistent morbidity despite early comprehensive management with external fixation.