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Solid Bolt Fixation of the Medial Column in Charcot Midfoot Arthropathy

Published:August 30, 2012DOI:https://doi.org/10.1053/j.jfas.2012.05.017

      Abstract

      Charcot medial column and midfoot deformities are associated with rocker bottom foot, recurrent plantar ulceration, and consequent infection. The primary goal of surgical intervention is to realign and stabilize the plantar arch in a shoe-able, plantigrade alignment. Different fixation devices, including screws, plates, and external fixators, can be used to stabilize the Charcot foot; however, each of these methods has substantial disadvantages. To assess the effectiveness of rigid, minimally invasive fixation of the medial column and midfoot, 8 cases of solid intramedullary bolt fixation for symptomatic Charcot neuroarthropathy were reviewed. The patients included 6 males (75%) and 2 females (25%), with a mean age of 63 (range 46 to 80) years. The Charcot foot deformity was caused by diabetic neuropathy in 7 cases (87.5%) and alcoholic neuropathy in 1 (12.5%). The mean duration of postoperative follow-up period was 27 (range 12 to 44) months. The mean radiographic correction of the lateral talar–first metatarsal angle was 15° (range 3° to 19°), and the mean radiographic correction of the dorsal midfoot dislocation was 9 (range −4 to 23) mm. The mean loss of correction of the lateral talar–first metatarsal angle and midfoot dislocation after surgery was 7° (range 0° to 26°) and 1 (range 0 to 7) mm, respectively. No bolt breakage was observed, and no cases of recurrent or residual ulceration occurred during the observation period. Bolt removal was performed in 3 cases (37.5%), 2 (25%) because of axial migration of the bolt into the ankle joint and 1 (12.5%) because of infection. The results of the present review suggest that a solid intramedullary bolt provides reasonable fixation for realignment of the medial column in cases of Charcot neuroarthropathy.

      Level of Clinical Evidence

      Keywords

      Charcot neuroarthropathy commonly causes chronic destructive arthropathy involving the joints of the foot and ankle. It occurs as a consequence of various peripheral neuropathies, most commonly as a result of diabetes mellitus (
      • Gupta R.
      A short history of neuropathic arthropathy.
      ,
      • Yablon C.M.
      • Duggal N.
      • Wu J.S.
      • Shetty S.K.
      • Dawson F.
      • Hochman M.G.
      A review of Charcot neuroarthropathy of the midfoot and hindfoot: what every radiologist needs to know.
      ). Tarsometatarsal joints are most frequently affected, followed by the hindfoot, ankle joint, and forefoot (
      • Robinson A.H.
      • Pasapula C.
      • Brodsky J.W.
      Surgical aspects of the diabetic foot.
      ). Typically, destruction of the Lisfranc joint complex causes flattening of the longitudinal foot arch (rocker bottom deformity), leading to plantar ulceration, which, especially in the course of diabetes, often results in infection and significant morbidity.
      When conservative management fails to heal or prevent recurrent ulceration, surgical treatment options must be considered (
      • Johnson J.
      Operative treatment of neuropathic arthropathy of the foot and ankle.
      ). The primary goal of surgical intervention is to realign and stabilize the plantar arch, often after first eradicating osteomyelitis and allowing the Charcot process to become quiescent (
      • Grant W.P.
      • Garcia-Lavin S.
      • Sabo R.
      Beaming the columns for Charcot diabetic foot reconstruction: a retrospective analysis.
      ,
      • Lamm B.M.
      • Gottlieb H.D.
      • Paley D.
      A two-stage percutaneous approach to Charcot diabetic foot reconstruction.
      ). The commonly used surgical procedure entails arthrodesis of the midfoot with or without hindfoot arthrodesis and Achilles tendon release (
      • Yablon C.M.
      • Duggal N.
      • Wu J.S.
      • Shetty S.K.
      • Dawson F.
      • Hochman M.G.
      A review of Charcot neuroarthropathy of the midfoot and hindfoot: what every radiologist needs to know.
      ,
      • Dalla Paola L.
      • Brocco E.
      • Ceccacci T.
      • Ninkovic S.
      • Sorgentone S.
      • Marinescu M.G.
      • Volpe A.
      Limb salvage in Charcot foot and ankle osteomyelitis: combined use single stage/double stage of arthrodesis and external fixation.
      ). Minimizing soft tissue damage during surgery is essential, because incomplete or slow healing is generally known to be associated with neuropathy, vasculopathy, dermopathy, and difficulty avoiding weightbearing activities, all of which are known to affect this patient population. Rigid osteosynthesis is also important owing to the high likelihood of uncontrolled postoperative weightbearing, which can lead to failure of the implants and reconstruction (
      • Johnson J.
      Operative treatment of neuropathic arthropathy of the foot and ankle.
      ).
      Several different types of bone fixation devices, including screws, plates, and external fixators, can be used to stabilize the reconstructed Charcot foot; however, each of these devices has substantial disadvantages that can affect the clinical course. Cannulated screws break easily, and although a combination of plates and screws is stronger than screws alone (
      • Marks R.M.
      • Parks B.G.
      • Schon L.C.
      Midfoot fusion technique for neuroarthropathic feet: biomechanical analysis and rationale.
      ), such constructs tend to be bulky and can cause soft tissue complications. External fixation is an excellent minimally invasive solution for accomplishing rigid fixation (
      • Dalla Paola L.
      • Brocco E.
      • Ceccacci T.
      • Ninkovic S.
      • Sorgentone S.
      • Marinescu M.G.
      • Volpe A.
      Limb salvage in Charcot foot and ankle osteomyelitis: combined use single stage/double stage of arthrodesis and external fixation.
      ,
      • Cooper P.S.
      Application of external fixators for management of Charcot deformities of the foot and ankle.
      ,
      • Farber D.C.
      • Juliano P.J.
      • Cavanagh P.R.
      • Ulbrecht J.
      • Caputo G.
      Single stage correction with external fixation of the ulcerated foot in individuals with Charcot neuroarthropathy.
      ,
      • Pinzur M.S.
      • Sostak J.
      Surgical stabilization of nonplantigrade Charcot arthropathy of the midfoot.
      ); however, the risk of pin site infection remains, and the fixators can be inconvenient to patients.
      Recently, several investigators have proposed restoring the alignment of the medial column (medial metatarsocuneiform, medial naviculocuneiform, and talonavicular joints) by intramedullary placement of a cannulated screw (
      • Assal M.
      • Stern R.
      Realignment and extended fusion with use of a medial column screw for midfoot deformities secondary to diabetic neuropathy.
      ,
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ). The clinical results have been favorable; however, screw breakage and migration is a substantial risk associated with this form of fixation owing to the decreased relative strength of a cannulated screw compared with a solid-core screw. With screw breakage, loss of alignment can occur, and additional surgical intervention can become necessary. In an effort to assess the clinical and radiographic outcomes of reconstruction of the Charcot foot using a solid fusion bolt for intramedullary beam stabilization of the medial column and midfoot, we undertook a review of 8 feet in 8 patients with neuroarthropathy and symptomatic rocker bottom foot.

      Patients and Methods

       Patient Population

      We conducted a review of consecutive patients who were seen in our clinic and treated for Charcot neuroarthropathy-associated midfoot collapse using midfoot fusion and a solid intramedullary fusion bolt. The regional ethics committed approved the investigation, and written informed consent for inclusion in the review was obtained. The medical records were reviewed by 1 of us (M.M.), who searched for patients using the diagnosis code for Charcot foot and the diagnosis code for arthropathy associated with other endocrine and metabolic disorders (International Classification of Diseases, 9th Revision, codes 713.5 and 713.0, respectively, World Health Organization, Geneva, Switzerland). To be included in the case series, all that was required was the diagnosis of Charcot foot and treatment using intramedullary beaming and the solid fusion bolt, along with preoperative and postoperative radiographs of the involved foot.

       Surgical Procedure

      Alignment of the medial column and midfoot, specifically the medial metatarsocuneiform, medial naviculocuneiform, and talonavicular joints, was restored and fixed using intramedullary placement of a 6.5-mm diameter solid bolt (Midfoot Fusion Bolt, Synthes, Zuchwil, Switzerland) (
      • Wiewiorski M.
      • Valderrabano V.
      Intramedullary fixation of the medial column of the foot with a solid bolt in Charcot midfoot arthropathy: case report.
      ). Joint realignment was performed with a full, open dissection. Joint resection of the medial column in preparation for fusion was performed (cases 1 through 4 and 8); alternatively, the joint surfaces where left intact (cases 5 through 7). The intramedullary bolt was inserted in either a retrograde fashion, directed from the distal end of the first metatarsal into the talus, or an antegrade fashion, directed from the posterolateral aspect of the talus into the first metatarsal. Additional midfoot joints were fused, if needed, using additional large diameter screws or other forms of internal fixation. If the Achilles tendon was found to be tight, effecting ankle equinus, the aponeurosis of the gastrocnemius or the Achilles tendon was lengthened before bone realignment. Postoperative care consisted of the use of a non–weightbearing orthosis for the first 12 weeks, followed by gradual progression to full weightbearing according to the clinical and radiographic findings.

       Clinical Assessment

      The medical records were reviewed, and the clinical history information was abstracted. The clinical examination at the last follow-up visit included the American Orthopaedic Foot and Ankle Society midfoot score (
      • Kitaoka H.B.
      • Alexander I.J.
      • Adelaar R.S.
      • Nunley J.A.
      • Myerson M.S.
      • Sanders M.
      Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes.
      ), Wagner ulcer grading (
      • Wagner F.W.
      A classification and treatment program for diabetic, neuropathic, and dysvascular foot problems.
      ), and the Inlow 60-Second Diabetic Foot Screen (
      • Inlow S.
      The 60-second foot exam for people with diabetes.
      ). The Inlow screening score reflects the residual risk of foot ulceration and ranges from 0 (lowest risk) to 23 (highest risk). We were also interested in whether the patients could ambulate with supportive shoe gear with or without a cane after surgery and healing.

       Radiologic Assessment

      All patients underwent pre- and postoperative radiographic imaging. The patterns of osseous deformity as described by Sammarco et al (
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ) were assigned to each Charcot foot. The skeletal structures were also classified according to the classification of Schon et al (
      • Schon L.C.
      • Easley M.E.
      • Cohen I.
      • Lam P.W.
      • Badekas A.
      • Anderson C.D.
      The acquired midtarsus deformity classification system—interobserver reliability and intraobserver reproducibility.
      ). Radiographic measurements were taken with the patient weightbearing in the preoperative setting, non–weightbearing in the immediate postoperative setting, and weightbearing at the last follow-up evaluation. The talar–first metatarsal angle was measured in the anteroposterior view, with positive value representing valgus deformity (
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ). The talar–first metatarsal angle and the calcaneal–fifth metatarsal angle were measured on the lateral radiographs, with negative values representing valgus deformity (
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ). Dorsal midfoot displacement was measured on the lateral radiographs according to the method described by Sammarco et al (
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ). A paired Student's t-test was performed to compare the radiographic measurements from the pre- and postoperative periods, with statistical significance defined at the 5% (p ≤ .05) level.

      Results

      From October 2007 to July 2010, we performed 10 unilateral midfoot arthrodeses in 10 patients using solid intramedullary bolt fixation of the medial column and midfoot. Two patients were lost to follow-up because they died, which was determined to be unrelated to their foot operation. We reviewed the clinical and radiographic data pertaining to the 8 remaining cases, and the demographic data are listed in Table 1. The study cohort consisted of 6 males (75%) and 2 females (25%), and their mean age was 63 (range 46 to 80) years. The mean postoperative follow-up duration was 27 (range 12 to 44) months. Of the 8 patients, 7 (87.5%) had diabetes mellitus, and 1 (12.5%) had alcoholic neuropathy. Of the 8 feet, 3 (37.5%) were stabilized with the bolt inserted in an antegrade fashion, and 5 (62.5%) were stabilized in a retrograde fashion. At surgery, 4 patients (50%) had a plantar ulcer. According to the Wagner ulcer grading system (
      • Wagner F.W.
      A classification and treatment program for diabetic, neuropathic, and dysvascular foot problems.
      ), 3 (37.5%) of the ulcers were grade 3 and 1 (12.5%) was grade 2. Of the 8 feet, 3 (37.5%) had a Sammarco grade 3 Charcot foot deformation, 3 (37.5%) had grade 1 deformation, and 1 (12.5%) had Sammarco grade 5 deformation (
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ). For the Schon classification of osseous deformation (
      • Schon L.C.
      • Easley M.E.
      • Cohen I.
      • Lam P.W.
      • Badekas A.
      • Anderson C.D.
      The acquired midtarsus deformity classification system—interobserver reliability and intraobserver reproducibility.
      ), 3 (37.5%) were type I, 3 (37.5%) were type III, and 1 (12.5%) was type IV. Five of the feet (62.5%) underwent concomitant fusion of other joints in the same foot. As can be seen in the radiographs (Figs. 1 and 2), stability after bolt insertion need not be associated with complete osseous fusion of the splinted joints.
      Table 1Patient characteristics (n = 8 feet in 8 patients)
      Patient No.Age (y)GenderFollow-up Period (months)Charcot Foot EtiologySammarco Classification
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      Schon Classification
      Type I, LisFranc's joint; type II, naviculocuneiform; type III, perinavicular; type IV, Chopart's joint; subclasses: A, above metatarsal–calcaneus plane; B, coplanar; C, below; a β stage is assigned if 1 of the following criteria is met: dislocation is present, the lateral talar–first metatarsal angle is ≥30°, the lateral calcaneal–fifth metatarsal angle is ≥0, or the anteroposterior talar–first metatarsal angle is ≥35°; an α stage can be assigned when all 4 features are absent.
      • Schon L.C.
      • Easley M.E.
      • Cohen I.
      • Lam P.W.
      • Badekas A.
      • Anderson C.D.
      The acquired midtarsus deformity classification system—interobserver reliability and intraobserver reproducibility.
      Preoperative UlcerPreoperative Wagner Ulcer Grade
      • Wagner F.W.
      A classification and treatment program for diabetic, neuropathic, and dysvascular foot problems.
      Mid-tarsal Bolt InsertionOther Fused Sites
      155Male23Diabetes3IIIBβNo0AntegradeSecond TMT (plate)
      263Female43DiabetesNANAYes3AntegradeNone
      368Male40Diabetes5IVCβNo0RetrogradeNone
      459Male12Diabetes3IIICβYes3RetrogradeFirst and second metatarsal, medial–intermediate cuneiform (plates)
      546Female28Diabetes3IIICαYes2RetrogradeNone
      680Male16Diabetes1IBαNo0RetrogradeFirst and second metatarsal, second, third, and fourth TMT, medial–intermediate cuneiform (screws)
      764Male44Diabetes1IBβNo0AntegradeFirst and second metatarsal, second and third TMT (screws)
      871Male12Alcoholism1ICβYes3RetrogradeFirst and second metatarsal, third TMT (screws)
      Mean63 (46–80)27 (12–44)
      Abbreviations: NA, not available; TMT, tarsometatarsal joint.
      Data in parentheses are ranges.
      Type I, LisFranc's joint; type II, naviculocuneiform; type III, perinavicular; type IV, Chopart's joint; subclasses: A, above metatarsal–calcaneus plane; B, coplanar; C, below; a β stage is assigned if 1 of the following criteria is met: dislocation is present, the lateral talar–first metatarsal angle is ≥30°, the lateral calcaneal–fifth metatarsal angle is ≥0, or the anteroposterior talar–first metatarsal angle is ≥35°; an α stage can be assigned when all 4 features are absent.
      Figure thumbnail gr1
      Fig. 1Exemplary case of successful treatment. (A and B) Preoperative weightbearing radiographs demonstrating failed previous midfoot fusion in patient 3. (C) Immediate postoperative non–weightbearing radiographs showing a realigned medial plantar arch, fixed by the antegrade inserted bolt. (D and E) Midfoot alignment was maintained at 40 months postoperatively.
      Figure thumbnail gr2
      Fig. 2Bolt migration. (A and B) Preoperative weightbearing radiographs demonstrating failed previous midfoot fusion in patient 7. (C and D) Postoperative radiographs showing correct position of the retrograde bolt. At 27 months after bolt fixation, the patient visited our clinic because of severe pain in the ankle joint. (E) Radiography revealed axial migration of the bolt into the ankle joint. The bolt was removed and the pain immediately resolved. (F) At the final follow-up examination, 13 months after bolt removal, the radiographs showed a slight loss of correction. However, the medial midfoot alignment was still improved compared with before bolt implantation.
      Figure thumbnail gr3
      Fig. 3Radiologic alignment. (A) Lateral talar–first metatarsal angle and (B) dorsal displacement were measured on the preoperative weightbearing radiographs, immediate postoperative non–weightbearing radiographs, and weightbearing radiographs at the final follow-up examination. The results for all cases are shown. Dotted lines indicate bolt removal cases (patients 6 through 8).
      The clinical and radiographic data are presented in Tables 2 and 3 and Fig. 3. No cases resulted in limb amputation, and all the patients were able to walk at least 1 block, with a cane in 2 (25%) and without a cane in 6 (75%) at the last follow-up evaluation. The mean American Orthopaedic Foot and Ankle Society midfoot score (
      • Kitaoka H.B.
      • Alexander I.J.
      • Adelaar R.S.
      • Nunley J.A.
      • Myerson M.S.
      • Sanders M.
      Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes.
      ) at the final follow-up evaluation was 67 (range 58 to 83). In addition, at the final follow-up visit, no cases of recurrent or residual ulceration had developed. The mean Inlow 60-Second Diabetic Foot Screen (
      • Inlow S.
      The 60-second foot exam for people with diabetes.
      ) score was 8 (range 5 to 11). Preoperative conventional radiographs were unavailable for 1 patient (12.5%; patient 2). Bolt migration occurred in a total of 3 cases (cases 5 through 7). Bolt removal became necessary in 3 patients (37.5%), 1 (12.5%) because of a deep infection followed by massive osteolysis and collapse of bone structure (patient 8) and 2 (25%) because of axial migration of the bolt into the ankle (patients 6 and 7). None of the bolts deformed or broke.
      Table 2Postoperative clinical and radiologic data at last follow-up visit
      None of the patients displayed neuropathic foot ulcer at the time of final follow-up, and none of the fusion bolts were broken.
      (n = 8 feet in 8 patients)
      Patient No.Follow-up (months)Inlow Diabetic Score
      • Inlow S.
      The 60-second foot exam for people with diabetes.
      AOFAS Midfoot Score
      • Kitaoka H.B.
      • Alexander I.J.
      • Adelaar R.S.
      • Nunley J.A.
      • Myerson M.S.
      • Sanders M.
      Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes.
      Cane Used to Aid AmbulationAxial Migration of BoltBolt Removal
      123969NoNoNo
      243558NoNoNo
      3401169NoNoNo
      412772NoNoNo
      528883NoYesNo
      616570NoYesYes
      Bolt migration.
      7441056YesYesYes
      Bolt migration.
      8
      Alcoholic peripheral neuropathy.
      12861YesNoYes
      Operative site infection.
      Mean27 (12–24)8 (5–11)67 (58–83)
      Abbreviations: AOFAS, American Orthopaedic Foot and Ankle Society.
      Data in parentheses are ranges.
      None of the patients displayed neuropathic foot ulcer at the time of final follow-up, and none of the fusion bolts were broken.
      Bolt migration.
      Alcoholic peripheral neuropathy.
      § Operative site infection.
      Table 3Comparison of preoperative and postoperative radiologic results (n = 8 feet in 8 patients)
      Patient No.PreoperativeImmediate PostoperativeLong-term Postoperative
      AP Talar–First Metatarsal Angle (°)Lateral Talar–First Metatarsal Angle (°)Lateral Calcaneal–Fifth Metatarsal Angle (°)Dorsal Midfoot Displacement (mm)AP Talar–First Metatarsal Angle (°)Lateral Talar–First Metatarsal Angle (°)Lateral Calcaneal–Fifth Metatarsal Angle (°)Dorsal Midfoot Displacement (mm)AP Talar–First Metatarsal Angle (°)Lateral Talar–First Metatarsal Angle (°)Lateral Calcaneal–Fifth Metatarsal Angle (°)Dorsal Midfoot Displacement (mm)
      14−231025−2−61722−6142
      2NANANANA4025040160
      316−20643−21003−290
      415−158113−31214−1124
      510−121628627010−3150
      619−201408−12945−71611
      728−181712−2337253212
      817−17−42010−1410010−4030
      Mean15.6−17.99.610.64.0−2.120.91.15.4−8.312.02.4
      SD8.87.27.59.54.56.010.11.53.013.56.73.8
      Maximum28−1217251063741032111
      Minimum4−23−40−2−141002−4020
      Abbreviations: AP, anteroposterior; NA, not available; SD, standard deviation.
      The amount of surgical correction was determined by comparing the preoperative weightbearing and immediate postoperative non–weightbearing radiographs taken immediately after surgery (Table 3). The mean correction values were as follows: anteroposterior talar–first metatarsal angle, 12° (range 2° to 30°); lateral talar–first metatarsal angle, 15° (range 3° to 21°); lateral calcaneal–fifth metatarsal angle, 11° (range 4° to 20°); and midfoot dorsal displacement, 9 (range −4 to 23) mm. These differences were all statistically significant (p < .05). Maintenance of the correction was determined by comparing the immediate postoperative non–weightbearing and long-term postoperative weightbearing foot radiographs (Table 3). The mean loss of correction was as follows: anteroposterior talar–first metatarsal angle, 2° (range −3° to 7°), lateral talar–first metatarsal angle, 7° (range 0° to 26°); lateral calcaneal–fifth metatarsal angle, 9° (range 1° to 16°); and midfoot dorsal displacement 1 (range 0 to 7) mm. A statistically significant (p < .05) postoperative decrease was seen in the lateral calcaneal–fifth metatarsal angle (p ≤ .05) but not in the other 3 measurements. A representative case of successful midfoot fusion with a solid bolt (patient 3) is shown in Fig. 1, and a case in which the bolt migrated and required subsequent removal (patient 7) is shown in Fig. 2.

      Discussion

      Charcot midfoot deformity is associated with recurrent plantar ulceration and consequent morbidity. The aim of surgery is, therefore, to achieve a plantigrade foot with normal plantar pressure distribution (
      • Yablon C.M.
      • Duggal N.
      • Wu J.S.
      • Shetty S.K.
      • Dawson F.
      • Hochman M.G.
      A review of Charcot neuroarthropathy of the midfoot and hindfoot: what every radiologist needs to know.
      ,
      • Simon S.R.
      • Tejwani S.G.
      • Wilson D.L.
      • Santner T.J.
      • Denniston N.L.
      Arthrodesis as an early alternative to nonoperative management of Charcot arthropathy of the diabetic foot.
      ). Although conservative treatment options are widely accepted as the first choice of treatment, the results are often unsatisfactory. Saltzman et al (
      • Saltzman C.L.
      • Hagy M.L.
      • Zimmerman B.
      • Estin M.
      • Cooper R.
      How effective is intensive nonoperative initial treatment of patients with diabetes and Charcot arthropathy of the feet?.
      ) reported that nonoperative treatment is associated with an approximately 2.7% annual rate of amputation, a 23% risk of requiring bracing for more than 18 months, and a 49% risk of recurrent ulceration.
      Surgical intervention to restore the plantar arch is typically a last resort option for patients in whom conservative treatment is not feasible or has failed. Therefore, patients undergoing reconstructive surgery usually present with a severe deformity. In our case series, the mean preoperative radiologic lateral talar–first metatarsal angle was −18°, and the mean midfoot dorsal dislocation was 11 mm. Such severe deformities require a substantial amount of realignment to effect satisfactory correction. In our case series, the mean correction of the lateral talar–first metatarsal angle and midfoot dorsal displacement angle was 15° and 9 mm, respectively. As such, a firm fixation method was necessary to try and maintain this amount of correction. Because patients with Charcot foot cannot control the weightbearing load owing to a lack of sensation and other morbidities (e.g., obesity, concomitant arthritis, visual deficits, cardiovascular disease), repetitive peak loads can lead to implant failure.
      To secure the realignment of the Charcot foot, skeletal fixation with screws, plates, and external fixation have been used (
      • Dalla Paola L.
      • Brocco E.
      • Ceccacci T.
      • Ninkovic S.
      • Sorgentone S.
      • Marinescu M.G.
      • Volpe A.
      Limb salvage in Charcot foot and ankle osteomyelitis: combined use single stage/double stage of arthrodesis and external fixation.
      ,
      • Cooper P.S.
      Application of external fixators for management of Charcot deformities of the foot and ankle.
      ,
      • Farber D.C.
      • Juliano P.J.
      • Cavanagh P.R.
      • Ulbrecht J.
      • Caputo G.
      Single stage correction with external fixation of the ulcerated foot in individuals with Charcot neuroarthropathy.
      ,
      • Pinzur M.S.
      • Sostak J.
      Surgical stabilization of nonplantigrade Charcot arthropathy of the midfoot.
      ,
      • Simon S.R.
      • Tejwani S.G.
      • Wilson D.L.
      • Santner T.J.
      • Denniston N.L.
      Arthrodesis as an early alternative to nonoperative management of Charcot arthropathy of the diabetic foot.
      ,
      • Embil J.M.
      • Trepman E.
      A case of diabetic Charcot arthropathy of the foot and ankle.
      ,
      • Horton G.A.
      • Olney B.W.
      Deformity correction and arthrodesis of the midfoot with a medial plate.
      ). Fixation of a single joint with conventional screws is no longer favored by many surgeons because of the frequent occurrence of screw breakage and loss of fixation (
      • Assal M.
      • Stern R.
      Realignment and extended fusion with use of a medial column screw for midfoot deformities secondary to diabetic neuropathy.
      ). Plates are stronger, and several investigators have addressed the successful fusion of midfoot bones by placement of a plate along the medial column (
      • Marks R.M.
      • Parks B.G.
      • Schon L.C.
      Midfoot fusion technique for neuroarthropathic feet: biomechanical analysis and rationale.
      ,
      • Simon S.R.
      • Tejwani S.G.
      • Wilson D.L.
      • Santner T.J.
      • Denniston N.L.
      Arthrodesis as an early alternative to nonoperative management of Charcot arthropathy of the diabetic foot.
      ,
      • Embil J.M.
      • Trepman E.
      A case of diabetic Charcot arthropathy of the foot and ankle.
      ,
      • Horton G.A.
      • Olney B.W.
      Deformity correction and arthrodesis of the midfoot with a medial plate.
      ). Marks et al (
      • Marks R.M.
      • Parks B.G.
      • Schon L.C.
      Midfoot fusion technique for neuroarthropathic feet: biomechanical analysis and rationale.
      ) demonstrated the biomechanical superiority of plantar plates for midfoot stabilization in a cadaver study. However, placement of a plate usually requires extensive dissection and exposure, resulting in accompanying soft tissue damage. Additionally, the implant construct can be bulky and increase tension in the overlying skin. External fixation has been recommended by several investigators (
      • Dalla Paola L.
      • Brocco E.
      • Ceccacci T.
      • Ninkovic S.
      • Sorgentone S.
      • Marinescu M.G.
      • Volpe A.
      Limb salvage in Charcot foot and ankle osteomyelitis: combined use single stage/double stage of arthrodesis and external fixation.
      ,
      • Cooper P.S.
      Application of external fixators for management of Charcot deformities of the foot and ankle.
      ,
      • Farber D.C.
      • Juliano P.J.
      • Cavanagh P.R.
      • Ulbrecht J.
      • Caputo G.
      Single stage correction with external fixation of the ulcerated foot in individuals with Charcot neuroarthropathy.
      ,
      • Pinzur M.S.
      • Sostak J.
      Surgical stabilization of nonplantigrade Charcot arthropathy of the midfoot.
      ). Pinzur and Sostak (
      • Pinzur M.S.
      • Sostak J.
      Surgical stabilization of nonplantigrade Charcot arthropathy of the midfoot.
      ) reported a series of 51 such patients with a minimum follow-up period of 1 year, in which the mean lateral talar–first metatarsal angle was reduced from 27.6° to 6.4°. However, external fixation is known to be associated with a substantial risk of pin site infection and patient inconvenience owing to the prominence of the frame.
      Rooney et al (
      • Rooney J.
      • Hutabarat S.R.
      • Grujic L.
      • Hansen Jr., S.T.
      Surgical reconstruction of the neuropathic foot.
      ) reported a method of fixing the medial column using intramedullary screws, and several investigators recently reported obtaining favorable results with this procedure (
      • Assal M.
      • Stern R.
      Realignment and extended fusion with use of a medial column screw for midfoot deformities secondary to diabetic neuropathy.
      ,
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ). Sammarco et al (
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ) reviewed 22 cases of midfoot arthrodesis with a cannulated screw and reported significant reduction and maintenance of the talar–first metatarsal and calcaneal–fifth metatarsal angles after a mean follow-up period of 52 months. The key advantage of this method is that a long incision and wide exposure is not required for fixation. However, the implants usually used for such procedures are large-diameter cannulated screws, and it has been shown that these screws carry a substantial risk of breakage. Sammarco et al (
      • Sammarco V.J.
      • Sammarco G.J.
      • Walker Jr., E.W.
      • Guiao R.P.
      Midtarsal arthrodesis in the treatment of Charcot midfoot arthropathy.
      ) used 6.5-mm cannulated screws and reported breakage of the screws in 8 (36.4%) of 22 cases.
      The main form of fixation used in the present patients was a 6.5-mm diameter, solid, headless bolt. At a mean follow-up duration of 27 months, no bolt breakage had occurred, and the midfoot alignment was maintained in all but 1 patient, in whom postoperative infection caused massive osteolysis and failure (patient 8). In our case series, correction of the calcaneal–fifth metatarsal angle was not maintained at the last follow-up examination. We believe this was because we did not always beam the lateral column, and the radiographic angle was determined using the non–weightbearing radiographs immediately after surgery. We believe that the lateral column fixation is, however, less important for favorable clinical results, although a longer follow-up period is needed to determine whether this theory is likely to be valid. Because 1 of the most important aims of realignment surgery for patients with Charcot foot is to avoid recurrent ulceration, and none of the patients in our series experienced postoperative ulceration or amputation during the observation period, it seems that beam stabilization of the medial column and midfoot is clinically beneficial, and the residual risk of foot ulceration is low according to the Inlow 60-Second Diabetic Screen.
      A drawback of the fusion bolt used in our patients is the predilection for axial migration, which we observed in 3 patients (37.5%). In 2 of those patients, the midfoot bolt penetrated into the ankle joint and necessitated subsequent implant removal. Interestingly, bolt migration occurred only in cases in which the intramedullary bolt was used to stabilize the medial column without necessarily aiming to fuse (no joint surface resection). We believe the reason for this was the short and shallow thread of the bolt, poor bone stock in patients with Charcot disease, and subsequent weightbearing on a foot that had not, in all cases, achieved solid, radiographic evidence of arthrodesis along the beamed column of bones. We hypothesized that changing the design of the bolt to 1 with a deeper and longer thread pattern might decrease the possibility of axial bolt migration. Also, the use of an interlocking mechanism, similar to that used in femoral and tibial intramedullary nails, might also minimize the risk of this complication.
      As with all retrospective case series, we appreciate that numerous methodologic limitations threaten the validity of any conclusions we have made. For instance, coding biases could have influenced our ability to identify potentially eligible patients, and we omitted 2 patients who had undergone the procedure but died of causes determined to be unrelated to Charcot foot surgery. Similarly, the retrospective design limited our ability to undertake an explanatory analysis, and we could not determine whether the comorbidities such as renal disease, obesity, or any other factors influenced our outcomes. Furthermore, we could not compare the pre- and postoperative clinical outcomes meaningfully. Still further, our emphasis was on radiographic measurement suggestive of a more normal pedal alignment, although the precise meaning of such measurements, whether weightbearing or not, in regard to subjective patient satisfaction is not known. We were also unable to determine the association of solid radiographic evidence of fusion with satisfactory long-term outcomes compared with the influence of beam stabilization without radiographic arthrodesis. Despite these shortcomings, we believe the results from the present series of patients imply that the solid fusion bolt can be used to stabilize the realigned foot in most patients with symptomatic medial column and midfoot Charcot deformation.
      In conclusion, the results of the present preliminary series of patients could be useful in the design of future prospective cohort studies and randomized controlled trials focusing on surgical repair of the Charcot foot.

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