Ilizarov external fixation in the correction of severe pediatric foot and ankle deformities

Complex rigid foot deformity correction with hexapod external fixator system

PURPOSE

Complex rigid foot deformities include three-plane deformities and usually presents with poor soft tissue coverage. In the last decades, gradual correction with computer-assisted fixator became an appropriate option for the treatment rigid foot deformities. This study aims to report our experience about treatment of complex foot deformities using Smart Correction fixator system®.

METHODS

We retrospectively analyzed 13 complex rigid foot deformities of ten consecutive patients treated with Smart Correction fixator system® from 2016 to 2020. Primary outcomes were classified as good, fair, and poor according to previously determined criteria. The outcomes were also assessed with The Manchester-Oxford Foot Questionnaire (MOXFQ). Non-parametric analysis (Wilcoxon test) for continuous variables and the Fisher's exact test for categorical variables were used.

RESULTS

Plantigrade foot was achieved in all patients after correction program. Supramalleolar osteotomy was applied in nine feet, midfoot osteotomy was applied in two feet, hindfoot osteotomy was required in one foot, and only soft tissue distraction performed in two feet. Two patients had recurrent deformity managed by further acute corrections. The mean MOXFQ scores improved from 72.7 preoperatively to 24.8 at last follow-up.

CONCLUSIONS

Present study shows that SCF the reliable option for the treatment of complex foot deformities, which also facilitates three-plane correction and concomitant lengthening with gradual soft tissue balance.

The Gradual Correction of Adult Severe Rigid Equinus Deformity Using Minimal Invasive U-Osteotomy With Taylor Spatial Frame

BACKGROUND

U-osteotomy with Taylor Spatial Frame correction is a rarely reported treatment method particularly well-suited for severe rigid equinus deformity in adults. The purpose of this study was to evaluate the effectiveness and efficacy of deformity correction and clinical outcome using this technique.

METHODS

We present a retrospective review of 30 feet in 26 patients who received U-osteotomy with Taylor Spatial Frame. Radiologic outcomes were measured using the anterior tibiotalar angle (TTA) with conventional weightbearing radiographs. Functional assessments included American Orthopaedic Foot & Ankle Society (AOFAS) ankle and hindfoot scores and patient satisfaction using Likert scale.

RESULTS

The etiology included trauma (9), neglected or relapsed clubfoot (6), spina bifida (5), poliomyelitis (4), Charcot-Marie-Tooth disease (4), and iatrogenic (2). All patients had equinus deformity with TTA more than 140 degrees (median 157.5, 141-177). There were varus deformity in 19 feet, limb length discrepancy in 6 legs, and genu procurvatum deformity in 2 legs. The duration of gradual correction was 53.6±13.5 days (33-73 days), and the external fixation time was 147.8±25.2 days (98-203 days). At last follow-up, TTA in all patients improved significantly (P < .001) to 113.5 degrees (111.8-116.0). All patients had plantigrade feet, except for 2 cases of residual mild equinovarus deformity, 2 cases of residual mild hindfoot varus deformity, 1 case of moderate hindfoot varus recurrence. The AOFAS scores significantly improved (P < .001) from 51.0 points (29.0-66.0) to 76.0 points (69.5-88.0). Eighteen patients were very satisfied, 6 patients were somewhat satisfied, and 2 patients were somewhat dissatisfied.

CONCLUSION

Using minimally invasive U-osteotomy with Taylor Spatial Frame to gradually correct the adult severe rigid equinus deformity proved to be an effective and relatively safe method associated with high patient satisfaction rates.

LEVEL OF EVIDENCE

Level IV, case series.

Post-traumatic severe ankle valgus and forefoot supination deformities treated by staged surgery using ilizarov technique and limited osteotomy: A case report

RATIONALE

Post-traumatic ankle valgus deformities are relatively rare. Old post-traumatic ankle deformity compounded by abundant scar contracture tissue formation around the joint is a big challenge for orthopedics. Conventional one-stage corrective osteotomy with internal fixation always results in many knotty postoperative complications, such as soft tissue avascular necrosis, implant-related infections, and distinct lower limb discrepancy. Here, we describe a patient with old post-traumatic severe ankle valgus and forefoot supination deformities and obtained satisfactory clinical results following multi-stage surgery using the Ilizarov technique and limited osteotomy. Even more encouraging, any complications of conventional one-stage surgery were successfully avoided through our treatment regimen.

PATIENT CONCERNS

A 24-year-old healthy man had post-traumatic 90-degree hindfoot valgus and forefoot supination deformities of the right foot for more than 10 years. The complicated issue was the vast, poorly vascularized scar contracture tissues tightly adhered to the bones of the lateral malleolus and dorsum pedis.

DIAGNOSES

Old post-traumatic severe ankle valgus and forefoot supination deformities and scar contracture of soft tissues of the foot and ankle joint.

INTERVENTIONS

In the first stage, Ilizarov external fixation was used to stretch the scar contracture tissue of the lateral malleolus. In the second stage, limited osteotomy of the tibiotalar joint and progressive closure of the osteotomy site were performed. In the third stage, Chopart joint osteotomy and slow forefoot pronation by external frame were performed.

OUTCOMES

Our treatment regimen not only guaranteed soft tissue safety, but also avoided infection and obvious lower limb discrepancy. At the 1-year follow-up, the patient acquired aesthetic and functional right foot.

LESSONS

Although relatively rare, old post-traumatic severe ankle valgus and forefoot supination deformities can be corrected using Ilizarov external fixation technology combined with limited osteotomy. With a well-designed staged operation scheme, soft tissue avascular necrosis, infection of the wound, obvious lower limb discrepancy, and flap grafting can be avoided.

Ilizarov Technique in Severe Pediatric Foot Disorders

The treatment of foot disorders in pediatric age with Ilizarov method is reserved for complex cases, cases in which it is not possible to perform acute corrections or cases that need bone and soft-tissue lengthening. Ilizarov method permits to correct any deformity. Correction can be achieved progressively with a closed procedure or combining the external fixator with a treatment involving soft or bone tissues. Complications are frequent; however, most of them do not affect the outcome of the treatment.

Comparison of three different correction trajectories for foot and ankle deformity treated by supramalleolar osteotomy using a novel external fixator

Based on the principle of distraction osteogenesis, external fixators are widely used in deformity correction of the foot and ankle. In this study, a novel ankle external fixator is proposed to correct complex multiplane deformities, especially for supramalleolar osteotomy to correct distal tibia deformities. The relatively simple structure and fewer struts in the proposed fixator reduce the complexity of adjusting the external fixator. Based on two existing adjustment strategies, a new strategy taking into account the orientation and shortest path of the ankle joint center is proposed, which is named joint adjustment for equal bone distraction. By proposing the inverse kinematic solutions of the novel external fixator, mathematical derivations of the bone trajectory and modelling of the bone shape for the three distraction strategies are performed. The results obtained by comparative analysis indicate that a uniformly spaced path of the ankle joint center can be acquired, and a smooth and uniform correction trajectory of the distal tibia end can be obtained using the new adjustment strategy. It can avoid bone end interference and only generates a maximum deviation 0.66% greater than the currently optimal 1 mm/day. The new strategy can perform multiplane corrections simultaneously, which shortens the correction time and reduces the patient's pain.

Complex foot deformities associated with lower limb deformities: a new therapeutic strategy for simultaneous correction using Ilizarov procedure together with osteotomy and soft tissue release

AIM

The aim of the current study is to introduce a new therapeutic strategy for simultaneous correction of complex foot deformities (CFD) and the associated lower limb deformities (LLD) by using Ilizarov technique with osteotomy and soft tissue procedure and to report its early clinical results.

METHODS

A retrospective review of CFD associated with LLD simultaneous correction utilizing the Ilizarov procedure together with osteotomy and soft tissue balance from 2015 to 2019 was conducted.

RESULTS

Thirty-two patients were followed for an average of 42.8 months. The mean external fixation time (EFT) was 6.5 months. The mean healing index (HI) was 1.7 months/cm. At the time of fixator removal, plantigrade feet were achieved in all patient and lower limb deformities were corrected. No recurrence of the deformities occurred. The mean LLRS AIM score was improved from 7.5 to 0.3. At the final follow-up, the ASAMI-Paley score was graded as excellent in all limbs in the aspect of bone results, and functional results were defined as excellent in 29 (90.6%) limbs and good in 3 (9.4%) limbs. The mean modified Dimeglio score was significantly improved from 7.2 to 1.3. No deep infection of the osteotomy site or nonunion was noted in the current study.

CONCLUSION

The therapeutic strategy by using the Ilizarov procedure together with osteotomy and soft tissue balance is a safe and effective way to simultaneously correct CFD and LLD.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Treatment Strategies and Frame Configurations in the Management of Foot and Ankle Deformities

To provide standardized nomenclature for various hexapod frame configurations for foot and ankle deformity correction, a unique classification of the hexapod external fixators was proposed. This classification is based on number of correction levels, secured anatomic blocks, and direction of the strut attachment. It allows the combination of all different foot and ankle frame assemblies into a few standard hexapod configurations, irrespective of which external fixator is used.

Treatment of the neglected and relapsed clubfoot

Treatment of the neglected and the relapsed clubfoot is one of the most controversial topics in pediatric foot care. This article reviews the breadth of treatment options for practicing podiatrists or orthopedists with a specialty in complex clubfoot treatment. Discussion includes the appropriate circumstances for the use of the different procedures presented and the author's preferred treatment algorithm, based on 15 years of treating neglected, relapsed, and nonidiopathic clubfeet.

The management of the neglected congenital foot deformity in the older child with the Taylor spatial frame

BACKGROUND

Neglected or inadequately treated rigid congenitally deformed feet in older children are a nightmarish challenge for the child, the parents, and the orthopaedic surgeon. Because of the multiplicity of spatial deformities exhibited by these feet and legs, it was hypothesized that correction using the Taylor spatial frame (TSF) would decrease morbidity, facilitate correction, and minimize treatment time in children from remote regions with extremely rigid deformed feet.

METHODS

Recent experience with the management of 11 such feet (Dimeglio type IV) in 9 children with an average age of 9.2 years using the TSF has been gratifying. Six children had associated leg length discrepancy, which was corrected by concomitant tibial lengthening. All feet underwent soft tissue releases, whereas forefoot and/or hindfoot osteotomies were performed in 7 feet.

RESULTS

All children attained plantigrade, functional feet, and were fully ambulatory and capable of wearing normal footwear. Complications were minor consisting of pin tract infections, residual metatarsus varus in 3, and wound dehiscence in 1. There were no neurovascular events. This was attributed to the slower 3 plane correction using the TSF technique as well as the elimination of the need for plaster immobilization thus allowing direct monitoring of the foot and limb.

CONCLUSIONS

The rigid foot deformity in the older child can be safely and effectively corrected with the aid of the TSF, which facilitates a 3 plane correction and concomitant limb lengthening.

Correction of complex equino cavo varus foot deformity in skeletally mature patients by Ilizarov external fixation versus staged external-internal fixation

BACKGROUND

Complex foot deformity is a multi-planar foot deformity with many etiologic factors. Different corrective procedures using Ilizarov external fixation have been described which include, soft tissue release, V-osteotomy, multiple osteotomies and triple fusion.

METHODS

In this study we compare the results of two groups of skeletally mature patients with complex foot deformity who were treated by two different protocols. The first group (27 patients, 29 feet) was treated by triple fusion fixed by Ilizarov external fixator until union. The second group (29 patients, 30 feet), was treated by triple fusion with initial fixation by Ilizarov external fixation until correction of the deformity was achieved clinically, and then the Ilizarov fixation was replaced by internal fixation using percutaneous screws. Both groups were compared as regard the surgical outcome and the incidence of complications.

RESULTS

There was statistically significant difference between the two groups regarding duration of external fixation and duration of casting with shorter duration in the group 2. Also there was statistically significant difference between both groups regarding pin tract infection with less incidence in group 2.

CONCLUSION

Early removal of Ilizarov external fixation after correction of the deformity and percutaneous internal fixation using 6.5 cannulated screws can shorten the duration of treatment and be more comfortable for the patient with a low risk of recurrence or infection.