Treatment of complex foot deformities with hexapod external fixator in growing children and young adult patients

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.

Accuracy of the hexapod external fixator in treating tibial angular deformities with or without limb length discrepancy: a retrospective study

OBJECTIVE

Hexapod external fixator systems allow simultaneous deformity correction in multiple planes as well as limb lengthening. The aim of this study is to evaluate the accuracy of a hexapod frame (smart correction frame) in different types of tibial deformities requiring correction with or without lengthening.

METHODS

A total of 54 tibial angular deformities and limb length discrepancies operated with a hexapod frame between January 2015 and January 2021 were classified into four groups: "Group A ( n  = 13): only lengthening," "Group B ( n  = 14): lengthening and uniplanar correction," "Group C ( n  = 16): only uniplanar correction," and "Group D ( n  = 11): biplanar correction." The accuracy of angular deformity correction/lengthening was calculated by dividing the actual correction/lengthening achieved after frame removal by the preoperative planned lengthening/correction.

RESULTS

The lengthening accuracy in Group A and Group B was 96.3 ± 7.1% and 95.7 ± 5.9%, respectively ( P  = 0.685). The angular deformity correction accuracy was 85.1 ± 9.9% for Group B, 85.2 ± 13.9% for Group C, and 80.2 ± 18.4% for Group D ( P  = 0.852). A revision program was performed in six cases (1 in Group B, 1 in Group C, and 4 in Group D) for full correction of the deformities.

CONCLUSION

The accuracy of tibial lengthening is high with the hexapod frame and is minimally affected by simultaneous deformity correction; however, the accuracy of angular correction slightly reduces as the deformity becomes more complex. Surgeons should be aware that reprogramming may be required after complex deformity correction.

Correction of a Complex Foot Deformity With V and Y Osteotomy and Ilizarov Method

Many authors consider the Ilizarov method as the best choice for correction of complex multiplanar foot deformities. Fifty-one patients, for a total of 55 feet, underwent V or Y osteotomy (respectively 32 and 23), 12 were due to congenital clubfoot outcomes, 11 were from post-traumatic pathologies, 9 from hemimelia, 7 from Charcot-Marie-Tooth, 5 from poliomyelitis, 3 from spina bifida, 2 from myopathy, 2 from poly-epiphyseal dysplasia, 1 from achondroplasia, 1 from arthrogryposis, 1 patient from Charcot's foot and 1 rheumatoid arthritis. All patients were contacted to undergo AOFAS and EQ-5D-5L questionnaire. The mean distraction time was 74.0 days (±25.3) and it was longer for V osteotomy (63.1 ± 21.1 vs 81.8 ± 25.4 days for Y and V respectively, p = .006). The average fixation time was 97.9 days (± 61.2), 90 days in the Y and 103 days in the V osteotomy groups. The mean preoperative foot length was longer in the group of Y osteotomy patients (158.7 ± 21.3 mm vs 133.5 ± 21.6 mm, p < .001). The mean length postoperatively was substantially the same (Y group 164.0 mm vs V group 167.4 mm, p < .562). The V osteotomy produces an elongation ratio of 440% with respect to that produced from the Y osteotomy (ratio length/distraction V/Y 0.44/0.1), with only 19% more in the distraction days. (81.8 V group vs 63.1 Y group). While the V osteotomy allows a lengthening of about 27%, the Y osteotomy, despite having correction potential superimposable to the V osteotomy, minimizes the elongation component.

Updates in the Surgical Management of Recurrent Clubfoot Deformity: a Scoping Review

PURPOSE OF REVIEW

This article focuses on the current advances in surgical management for clubfoot deformity, supported by up-to-date longitudinal studies on each approach.

RECENT FINDINGS

Long-term analysis following primary and repeated soft tissue releases has demonstrated good results in young patients with low relapse rates. Tibialis anterior transfer following the Ponseti method shows no difference in long-term pedographic analysis in comparison to the Ponseti method alone. Furthermore, tibialis anterior transfer following surgical relapses provides good long-term results with improved correction in talus-first metatarsal angle. Bony osteotomies may also play a role in addressing surgical relapses in older children. However, talar neck osteotomy may result in avascular necrosis of the talar dome. Hexapod external fixation may be considered by experienced surgeons to correct rigid clubfoot deformities in older patients with good long-term results and drastic improvements in pain perception. Long-term analysis of anterior distal tibial epiphysiodesis (ADTE) for recurrent equinus deformity following surgical correction has demonstrated statistical improvements in the anterior distal tibial angle (ADTA) and ankle dorsiflexion. Talectomy and naviculectomy are rarely used in today's practice as long-term studies have demonstrated high relapse rates and residual pain impeding patient mobility. Surgical correction following failure of the conservative approaches can be implemented to achieve full correction in clubfoot deformity. It is difficult to achieve a plantigrade feet with pain-free gait with repeated surgical interventions. Therefore, proper choice of the initial surgical technique is essential for achieving satisfactory long-term outcomes.

The Novel Application of Three-Dimensional Printing Assisted Patient-Specific Instrument Osteotomy Guide in the Precise Osteotomy of Adult Talipes Equinovarus

Objective

This current research is aimed at assessing clinical efficacy and prognosis of three-dimensional (3D) printing assisted patient-specific instrument (PSI) osteotomy guide in precise osteotomy of adult talipes equinovarus (ATE).

Methods

We included a total of 27 patients of ATE malformation (including 12 males and 15 females) from June 2014 to June 2018 in the current research. The patients were divided into the routine group (n = 12) and 3D printing group (n = 15) based on different operative methods. The parameters, including the operative time, intraoperative blood loss, complications, time to obtain bony fusion, functional outcomes based on American Orthopedic Foot and Ankle Society (AOFAS), and International Congenital Clubfoot Study group (ICFSG) scoring systems between the two groups were observed and recorded regularly.

Results

The 3D printing group exhibits superiorities in shorter operative time, less intraoperative blood loss, higher rate of excellent, and good outcomes presented by ICFSG score at last follow-up (P < 0.001, P < 0.001, P = 0.019) than the routine group. However, there was no significant difference exhibited in the AOFAS score at the last follow-up and total rate of complications between the two groups (P = 0.136, P = 0.291).

Conclusion

Operation assisted by 3D printing PSI osteotomy guide for correcting the ATE malformation is novel and feasible, which might be an effective method to polish up the precise osteotomy of ATE malformation and enhance the clinical efficacy.

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.

Multiplanar correction of proximal tibial recurvatum deformity with tibial osteotomy and computer assisted fixator

BACKGROUND

Several treatment modalities including open wedge osteotomies and Ilizarov reconstruction have been described for treatment of Proximal tibial recurvatum (PTR). However, the literature lacks information regarding the multiplanar correction of PTR using the computer assisted hexapod external fixator. The aim of the study is to present the results of PTR treatment with a computer assisted fixator systems.

METHODS

There were three female and three male patients (10 lower extremities) with a mean age of 20.6 years (7.3 to 25.2y) in the study group. The angle of genu recurvatum (aGR), the tibial plateau tilt angle (aTP), the mechanical posterior proximal tibial angle (mPPTA) and sagittal mechanical axis deviation (MADs) was measured for the sagittal plane assessment.

RESULTS

Preoperative sagittal assessment showed that the mean aGR was 28.9°±6.8°, mean aTP was 64.5°±10.2° and mean mPPTA was mPPTA was 114.1° ±10.3°. At the final follow-up there was a significant correction (p < 0.05 for aGR, aTP and mPPTA). Mean MADs was improved from 66.1 ± 14.2 mm to 16.6 ± 5.1 mm (p:0.005). Mean A:B ratio was 0.92 ± 0.13 preoperatively and 0.89 ± 0.14 postoperatively (p:0.37). Nine out of 10 knees had valgus deformity and mean preoperative tibiofemoral anatomic angle (TFA) was improved from 10.8°±3.7° valgus to 6.5°±1.7° valgus.

CONCLUSION

The treatment of PTR deformity with a computer-assisted hexapod external fixator is safe and effective. It provides multiplanar correction of the deformity with a high precision and the patellar alignment remains stable during the correction.

From Codivilla to Ponseti: historical narrative review on clubfoot treatment in Italy

Objective

This narrative review aims to summarize the historical steps of clubfoot treatment in Italy, identifying the centuries-old historical advancement in the deformity management and the most influent involved people.

Background

Clubfoot, also referred to as congenital talipes equinovarus, is a relatively common deformity that has significative consequences in the child if it is left untreated. Effective and early treatment of clubfoot has been praised as one of the most successful practice of modern pediatric orthopedics and both surgical and conservative techniques have been proposed over the decades. As an example, Codivilla’s posteromedial release (PMR) has been known internationally as one of the milestones of surgical treatment.

Methods

The narrative review includes clinical studies and reviews concerning clubfoot that were written in English, German and Italian. As an historical review, no limits of years were considered. The search was performed using PubMed, Google Scholar, Scopus, Medline and Cochrane Library databases up to January 2021. A combination of search terms including ‘history’, ‘clubfoot’, ‘conservative management’, ‘Codivilla’, ‘Ponseti method’, ‘relapse’ was utilized. Particular attention was given to papers written by Italian authors.

Conclusions

Current clubfoot treatment arises from several studies and clinical research over the centuries. Many surgeons, starting from mid-16th century, have studied the deformity trying to find a successful and effective technique to achieve full correction. Italian scientists, surgeons and prestigious institutions surely took part in this process.

International recognition of the Ilizarov bone reconstruction techniques: Current practice and research (dedicated to 100th birthday of G. A. Ilizarov)

The Ilizarov method is one of the current methods used in bone reconstruction. It originated in the middle of the past century and comprises a number of bone reconstruction techniques executed with a ring external fixator developed by Ilizarov GA. Its main merits are viable new bone formation through distraction osteogenesis, high union rates and functional use of the limb throughout the course of treatment. The study of the phenomenon of distraction osteogenesis induced by tension stress with the Ilizarov apparatus was the impetus for advancement in bone reconstruction surgery. Since then, the original method has been used along with a number of its modifications developed due to emergence of new fixation devices and techniques of their application such as hexapod external fixators and motorized intramedullary lengthening nails. They gave rise to a relatively new orthopedic subspecialty termed “limb lengthening and reconstruction surgery”. Based on a comprehensive literature search, we summarized the recent clinical practice and research in bone reconstruction by the Ilizarov method with a special focus on its modification and recognition by the world orthopedic community. The international influence of the Ilizarov method was reviewed in regard to the origin country of the authors and journal’s rating. The Ilizarov method and other techniques based on distraction osteogenesis have been used in many countries and on all populated continents. It proves its international significance and confirms the greatest contribution of Ilizarov GA to bone reconstruction surgery.

Influence of parameter deviation on the closeness of the tibial limb and external fixator based on a novel collision detection algorithm

The Ortho-SUV frame (OSF) is a hexapod external fixator widely applied in orthopedics deformity correction. The possibility of collision between OSF's struts and the soft tissue is an essential but overlooked issue. To avoid the issue, a novel collision detection algorithm is established based on a cone-cylinder model of the tibial limb-strut interaction for detecting the closeness of the tibial limb and external fixator. The algorithm is constructed using the vector analysis based on the model of the minimum distance between the truncated cone generatrix and the cylinder axis. The motion simulation is performed on the overall alignment through the Solidworks-motion module to verify the feasibility of the algorithm. Subsequently, the installation parameter deviations of the bone-fixator system are described to investigate the influence of orientation and position deviation on the closeness of the tibial limb and external fixator through the numerical method. The investigation results show that the orientation deviation γ (around the z-axis), the position deviation τ₁ and τ₂ (along the x and y-axes, respectively) have greater sensitivity to closeness and the influence of multiple deviations on the closeness has the property of superposition. The proposed algorithm can assist clinicians to strictly design and appraise frame configurations prior to their application to avoid the collision between the external fixator and the limbs during the correction. It has great application significance in the development of computer-aided correction software.