Neuropathic Midfoot Research Articles

Polymethylmethacrylate (PMMA) Augmentation Enhances the Mechanical Characteristics of Midfoot Beam Constructs in Charcot Neuroarthropathy Cadaver Model.

Even with the best conservative care, patients with Charcot neuroarthropathy (CN) of the foot and ankle often ulcerate, increasing their risk of infection, amputation, and death. Surgical fixation has been associated with risk of recurrent ulceration, potentially due to poor bone quality prone to recurrent deformity and ulceration. We propose midfoot beam reconstruction with PMMA augmentation as a novel means of improving fixation. A protocol was developed to create characteristic CN midfoot fragmentation both visually and fluoroscopically in each of 12 matched-pair cadaveric feet. Afterward, the pairs were divided into 2 groups: (1) midfoot beam fusion surgery alone, and (2) midfoot beam fusion surgery augmented with PMMA. A solid 7.0-mm beam was placed into the medial column and a solid 5.5-mm beam was placed across the lateral column. In the PMMA group, 8 to 10 mL of PMMA was inserted into the medial column. The hindfoot of each specimen was potted and the metatarsal heads were cyclically loaded for 1800 cycles, followed by load to failure while load and displacement were continually recorded. One specimen in the beam alone group failed before reaching the 1800th cycle and was not included in the failure analysis. The midfoot beam only group demonstrated greater mean displacement during cycle testing compared with the PMMA group, P < .05. The maximum force (N), stiffness (N/mm), and toughness (Nmm) were all significantly greater in the group augmented with PMMA, P < .05. In a CN cadaveric model, PMMA augmentation significantly decreased gapping during cyclic loading and nearly doubled the load to failure compared with midfoot beams alone. The results of this biomechanical study demonstrate that augmentation of midfoot beams with PMMA increases the strength and stiffness of the fusion construct. This increased mechanical toughness may help reduce the risk of nonunion and infection in patients with neuropathic midfoot collapse.

Republication of "Preliminary Experience Using Bioactive Glass Wedges for Cotton Osteotomy".

Medial cuneiform dorsal opening wedge (Cotton) osteotomy is often used for treating forefoot varus in patients undergoing surgery for stage II posterior tibialis tendon dysfunction. The goal of this study was to examine the radiographic outcomes of Cotton osteotomy with bioactive glass wedge to assess for both maintenance of correction and clinical results and complications. We hypothesized that bioactive glass wedges would maintain correction of the osteotomy with low complication rates. Between December 2015 and June 2016, the charts of 17 patients (10 female and 7 male) who underwent Cotton osteotomy using bioactive glass wedges were retrospectively reviewed. Patient age averaged 56.8 years (range, 16-84). The average follow-up was 6.5 months. Radiographs were reviewed to assess for initial correction and maintenance of correction of medial column sag as well as for union. Charts were reviewed for complications. The medial column sag correction averaged 15.6% on the final postoperative lateral radiograph. Meary angle averaged 19 degrees (3.14-42.8 degrees) preoperatively and 5.5 degrees (0.4-20.7 degrees) at final follow-up. All patients achieved clinical and radiographic union. One patient developed neuropathic midfoot pain and was managed with sympathetic blocks. One patient had a delayed union that healed at 6 months without surgical intervention. No patients required the use of custom orthotics or subsequent surgical procedures. Cotton osteotomy with bioactive glass wedges produced consistent correction of the medial column with low risk. Level IV, case series.

Novel Pathology Classification System (FEMASK-Score) for Charcot Neuropathic Arthropathy Reveals Intraneural Vasculopathy and Predicts Outcome

Category:Basic Sciences/Biologics; Ankle; Diabetes; Midfoot/ForefootIntroduction/Purpose:Charcot neuropathic arthropathy (CNA) is a debilitating, rapidly destructive degenerative joint disease that occurs in diabetic, neuropathic midfoot. Clinicoradiologic assessment for CNA previously relied on Eichenholtz Stage. There is limited data on CNA histopathology. The goal of this study was to independently develop a histopathologic scoring system for Charcot neuropathic arthropathy.Methods:Retrieval of surgical pathology specimens from neuroarthropathic CNA patients (2012-2019) were analyzed to evaluate joint soft tissue and bone. Considering progression from large to small periarticular bone fragments to resolution, we devised and applied a CNA FEMASK-score (named after coauthors): 0= intraneural arteriolosclerosis; 1= large bone fragments without host histiocytic response; 2= mixed bone fragments with host histiocytic response; 3= small minute bone spicules resorption to fibrosis. Clinical modified Eichenholtz staging and outcome were then compared the CNA FEMASK-score to assess for associations between these three elements.Results:Forty-eight cases of CNA included 34 males and 14 females, mean age 60.3 and age range 28-83 years, with clinical diabetes mellitus (predominantly Type II) and longstanding neuropathy. Elevated HbA1C, Eichenholtz stage, American Society of Anesthesia score, and Charlson comorbidity index were predictive of amputation. Pathologic specimens varied from fixation tissue to amputation. In addition to neurotraumatic, neurovascular and inflammatory findings, a distinctive intraneural hyalinized arteriolosclerosis was observed. FEMASK-scores:1 = 10%, 2= 58%, and 3=32%. FEMASK-score comparisons were 98% accurate compared with the modified Eichenholtz criteria scores of each patient and 98% reproducible among pathologists. FEMASK 2 and 3 correlates strongly with amputation.Conclusion:Our novel CNA FEMASK-score classification, derived from the largest cohort of diabetic neuropathic specimens, is reproducible, explains pathophysiology, correlates with Eichenholtz, and predicts amputation. The unique intraneural vasculopathy observed contributes to CNA etiology.

Novel FEMASK-score, a histopathologic assessment for destructive Charcot neuropathic arthropathy, reveals intraneural vasculopathy and correlates with progression and best treatment

BackgroundCharcot neuropathic arthropathy is a debilitating, rapidly destructive degenerative joint disease that occurs in diabetic, neuropathic midfoot. Clinicoradiologic assessment for Charcot neuropathic arthropathy previously relied on Eichenholtz stage. There is limited histopathologic data on this entity. We wanted to independently develop a histopathologic scoring system for Charcot neuropathic arthropathy. DesignRetrieval of surgical pathology midfoot specimens from Charcot patients (2012–2019) were analyzed to evaluate joint soft tissue and bone. Considering progression from large (≥half 40× hpf) to small (<half 40× hpf) periarticular bone fragments to resolution, we devised and applied a Charcot neuropathic arthropathy novel FEMASK-score (named after coauthors: Fanburg-Smith, Frauenhoffer, Flemming, Fritsche, Elfar, Murie, Aynardi, Stauch, Smith, King, and Klein): 0 (initial) = the observed intraneural arteriolosclerosis in all diabetic neuropathic patient specimens (not observed in other diabetic nerves); and finally scored with the most destruction observed: 1 = large bone fragments without host histiocytic response; 2 = mixed bone fragments with host histiocytic response; 3 = small minute bone spicules resorption to fibrosis. Eichenholtz stage and outcome were then compared. ResultsForty-eight cases of Charcot neuropathic arthropathy included 34 males and 14 females, mean age 60.3 and age range 28–83 years, with clinical diabetes mellitus (predominantly Type II) and longstanding neuropathy. Elevated HbA1C, Eichenholtz stage, American Society of Anesthesia score, and Charlson comorbidity index indicated initial clinical amputation. Pathologic specimens varied from fixation tissue to amputation. In addition to neurotraumatic, neurovascular and inflammatory findings, a distinctive intraneural hyalinized arteriolosclerosis was observed. FEMASK-scores: 1 = 10%, 2 = 58%, and 3 = 32%. Score comparisons were 98% accurate compared with Eichenholtz and 98% reproducible among pathologists. FEMASK 2 and 3 correlate with clinical need for amputation. ConclusionsOur novel Charcot neuropathic arthropathy FEMASK-score classification, derived from the largest cohort of diabetic neuropathic specimens, is reproducible, explains pathophysiologic progression of destructive phase of Charcot, correlates with Eichenholtz, and predicts progression to or clinical need for amputation. The unique intraneural vasculopathy observed contributes to Charcot neuropathic arthropathy etiology.

Preliminary Experience Using Bioactive Glass Wedges for Cotton Osteotomy

Background: Medial cuneiform dorsal opening wedge (Cotton) osteotomy is often used for treating forefoot varus in patients undergoing surgery for stage II posterior tibialis tendon dysfunction. The goal of this study was to examine the radiographic outcomes of Cotton osteotomy with bioactive glass wedge to assess for both maintenance of correction and clinical results and complications. We hypothesized that bioactive glass wedges would maintain correction of the osteotomy with low complication rates. Methods: Between December 2015 and June 2016, the charts of 17 patients (10 female and 7 male) who underwent Cotton osteotomy using bioactive glass wedges were retrospectively reviewed. Patient age averaged 56.8 years (range, 16-84). The average follow-up was 6.5 months. Radiographs were reviewed to assess for initial correction and maintenance of correction of medial column sag as well as for union. Charts were reviewed for complications. Results: The medial column sag correction averaged 15.6% on the final postoperative lateral radiograph. Meary angle averaged 19 degrees (3.14-42.8 degrees) preoperatively and 5.5 degrees (0.4-20.7 degrees) at final follow-up. All patients achieved clinical and radiographic union. One patient developed neuropathic midfoot pain and was managed with sympathetic blocks. One patient had a delayed union that healed at 6 months without surgical intervention. No patients required the use of custom orthotics or subsequent surgical procedures. Conclusion: Cotton osteotomy with bioactive glass wedges produced consistent correction of the medial column with low risk. Level of Evidence: Level IV, case series.

Neuropathic midfoot deformity: associations with ankle and subtalar joint motion.

BackgroundNeuropathic deformities impair foot and ankle joint mobility, often leading to abnormal stresses and impact forces. The purpose of our study was to determine differences in radiographic measures of hind foot alignment and ankle joint and subtalar joint motion in participants with and without neuropathic midfoot deformities and to determine the relationships between radiographic measures of hind foot alignment to ankle and subtalar joint motion in participants with and without neuropathic midfoot deformities.MethodsSixty participants were studied in three groups. Forty participants had diabetes mellitus (DM) and peripheral neuropathy (PN) with 20 participants having neuropathic midfoot deformity due to Charcot neuroarthropathy (CN), while 20 participants did not have deformity. Participants with diabetes and neuropathy with and without deformity were compared to 20 young control participants without DM, PN or deformity. Talar declination and calcaneal inclination angles were assessed on lateral view weight bearing radiograph. Ankle dorsiflexion, plantar flexion and subtalar inversion and eversion were assessed by goniometry.ResultsTalar declination angle averaged 34±9, 26±4 and 23±3 degrees in participants with deformity, without deformity and young control participants, respectively (p< 0.010). Calcaneal inclination angle averaged 11±10, 18±9 and 21±4 degrees, respectively (p< 0.010). Ankle plantar flexion motion averaged 23±11, 38±10 and 47±7 degrees (p<0.010). The association between talar declination and calcaneal inclination angles with ankle plantar flexion range of motion is strongest in participants with neuropathic midfoot deformity. Participants with talonavicular and calcaneocuboid dislocations result in the most severe restrictions in ankle joint plantar flexion and subtalar joint inversion motions.ConclusionsAn increasing talar declination angle and decreasing calcaneal inclination angle is associated with decreases in ankle joint plantar flexion motion in individuals with neuropathic midfoot deformity due to CN that may contribute to excessive stresses and ultimately plantar ulceration of the midfoot.

Midtarsal Arthrodesis in the Treatment of Charcot Midfoot Arthropathy

Fracture-dislocation of the midfoot with collapse of the longitudinal arch is common in patients with neuropathic arthropathy of the foot. In this study, we describe a technique of midfoot arthrodesis with use of intramedullary axial screw fixation and review the results and complications following use of this technique. A retrospective study of twenty-two patients who had undergone surgical reconstruction and arthrodesis to treat Charcot midfoot deformity was performed. Bone resection and/or osteotomy were required to reduce deformity. Axially placed intramedullary screws, inserted either antegrade or retrograde across the arthrodesis sites, were used to restore the longitudinal arch. Radiographic measurements were recorded preoperatively, immediately postoperatively, and at the time of the last follow-up and were analyzed in order to assess the amount and maintenance of correction. Patients were evaluated clinically and radiographically at an average of fifty-two months. Complete osseous union was achieved in sixteen of the twenty-two patients, at an average of 5.8 months. There were five partial unions in which a single joint did not unite in an otherwise stable foot. There was one nonunion, with recurrence of deformity. All patients returned to an independent functional ambulatory status within 9.5 months. Weight-bearing radiographs showed the talar-first metatarsal angle, the talar declination angle, and the calcaneal-fifth metatarsal angle to have improved significantly and to have been corrected to nearly normal values by the surgery. All measurements remained significantly improved, as compared with the preoperative values, at the time of final follow-up. There were no recurrent dislocations. Three patients had a recurrent plantar ulcer at the metatarsophalangeal joint that required additional surgery. There were eight cases of hardware failure. Open reduction and arthrodesis with use of multiple axially placed intramedullary screws for the surgical correction of neuropathic midfoot collapse provides a reliable stable construct to achieve and maintain correction of the deformity.

Realignment and Extended Fusion with Use of a Medial Column Screw for Midfoot Deformities Secondary to Diabetic Neuropathy

The failure of nonsurgical treatment of patients with midfoot and hindfoot deformity secondary to diabetic Charcot arthropathy may lead to a rocker-bottom foot deformity with recurrent or persistent plantar ulceration. We report our experience with realignment and extended fusion with primary use of a medial column screw for this midfoot deformity. From July 2001 through July 2005, we performed reconstructive surgery on fifteen adults with diabetes mellitus who had a severe neuropathic midfoot deformity consisting of a collapsed plantar arch with a rocker-bottom foot deformity. Thirteen had a nonhealing midfoot plantar ulcer. All underwent realignment and arthrodesis with a medial column screw; some required additional fixation techniques depending on the extent of the deformity. Outcome measures included ulcer and surgical wound-healing, radiographic results, complications, and the need for amputation. The mean duration of clinical follow-up was forty-two months. Fourteen patients were able to walk, and there were no recurrent plantar ulcers. Thirteen patients were able to wear custom-made extra-depth, wide-toed shoes with molded inserts. One patient without prior ulceration had development of a deep infection that necessitated an amputation. Four feet had a nonunion, one of which was symptomatic requiring a revision to obtain union. Surgical reconstruction of a collapsed neuropathic foot deformity is technically demanding, but a successful outcome can result in a plantigrade foot that is free of ulceration and abnormal pressure points and a patient who is able to walk. The procedure described has an acceptable degree of complications although it has a high rate of nonunion.

Realignment and Extended Fusion with Use of a Medial Column Screw for Midfoot Deformities Secondary to Diabetic Neuropathy

The failure of nonsurgical treatment of patients with midfoot and hindfoot deformity secondary to diabetic Charcot arthropathy may lead to a rocker-bottom foot deformity with recurrent or persistent plantar ulceration. We report our experience with realignment and extended fusion with primary use of a medial column screw for this midfoot deformity. From July 2001 through July 2005, we performed reconstructive surgery on fifteen adults with diabetes mellitus who had a severe neuropathic midfoot deformity consisting of a collapsed plantar arch with a rocker-bottom foot deformity. Thirteen had a nonhealing midfoot plantar ulcer. All underwent realignment and arthrodesis with a medial column screw; some required additional fixation techniques depending on the extent of the deformity. Outcome measures included ulcer and surgical wound-healing, radiographic results, complications, and the need for amputation. The mean duration of clinical follow-up was forty-two months. Fourteen patients were able to walk, and there were no recurrent plantar ulcers. Thirteen patients were able to wear custom-made extra-depth, wide-toed shoes with molded inserts. One patient without prior ulceration had development of a deep infection that necessitated an amputation. Four feet had a nonunion, one of which was symptomatic requiring a revision to obtain union. Surgical reconstruction of a collapsed neuropathic foot deformity is technically demanding, but a successful outcome can result in a plantigrade foot that is free of ulceration and abnormal pressure points and a patient who is able to walk. The procedure described has an acceptable degree of complications although it has a high rate of nonunion.

Midtarsal Arthrodesis in the Treatment of Charcot Midfoot Arthropathy

Fracture-dislocation of the midfoot with collapse of the longitudinal arch is common in patients with neuropathic arthropathy of the foot. In this study, we describe a technique of midfoot arthrodesis with use of intramedullary axial screw fixation and review the results and complications following use of this technique. A retrospective study of twenty-two patients who had undergone surgical reconstruction and arthrodesis to treat Charcot midfoot deformity was performed. Bone resection and/or osteotomy were required to reduce deformity. Axially placed intramedullary screws, inserted either antegrade or retrograde across the arthrodesis sites, were used to restore the longitudinal arch. Radiographic measurements were recorded preoperatively, immediately postoperatively, and at the time of the last follow-up and were analyzed in order to assess the amount and maintenance of correction. Patients were evaluated clinically and radiographically at an average of fifty-two months. Complete osseous union was achieved in sixteen of the twenty-two patients, at an average of 5.8 months. There were five partial unions in which a single joint did not unite in an otherwise stable foot. There was one nonunion, with recurrence of deformity. All patients returned to an independent functional ambulatory status within 9.5 months. Weight-bearing radiographs showed the talar-first metatarsal angle, the talar declination angle, and the calcaneal-fifth metatarsal angle to have improved significantly and to have been corrected to nearly normal values by the surgery. All measurements remained significantly improved, as compared with the preoperative values, at the time of final follow-up. There were no recurrent dislocations. Three patients had a recurrent plantar ulcer at the metatarsophalangeal joint that required additional surgery. There were eight cases of hardware failure. Open reduction and arthrodesis with use of multiple axially placed intramedullary screws for the surgical correction of neuropathic midfoot collapse provides a reliable stable construct to achieve and maintain correction of the deformity.

A Treatment Algorithm for Neuropathic (Charcot) Midfoot Deformity

Forty-nine feet in 47 patients with midfoot neuropathic foot deformity were referred for care to a comprehensive foot salvage clinic and followed for an average of 3.6 years. Twenty-three initially presented without open ulcers. Two underwent elective Syme's ankle disarticulation amputation, and the others were kept ambulatory with a combination of periods of nonweightbearing cast immobilization, accommodative extra-depth shoes with custom orthotics, and ankle-foot orthoses. Twenty-six of the feet initially presented for care with open ulcers and/or chronic osteomyelitis. Twenty-two of these patients underwent 32 surgical procedures. Sixteen underwent debridement of the infected bone and surrounding soft tissues. Excision of large, nonaccommodative boney prominence, termed exostectomy, was performed in eight. Partial excision of the deformed midfoot combined with boney stabilization and attempted arthrodesis, termed partial tarsectomy, were performed in seven. All surgical patients were managed postoperatively with long-term custom accommodative bracing. Follow-up at an average of 3.6 years revealed that all but one of the patients remained ambulatory. Six walk with accommodative shoe gear and persistent stable chronic open ulcers. None required below-knee amputation. Five amputations were performed, three at the Syme's ankle disarticulation level, one at the Chopart's hind-foot level, and one at the mid-foot level.(ABSTRACT TRUNCATED AT 250 WORDS)