Bioabsorbable implants for subtalar arthroereisis in pediatric flatfoot

Arthroereisis in juvenile flexible flatfoot: Which device should we implant? A systematic review of literature published in the last 5 years

BACKGROUND

Flexible flatfoot (FFF) is a very common condition in children, characterized by the loss of the medial arch and by an increase in the support base with valgus of the hindfoot. Arthroereisis (AR) procedures are widely performed corrective surgeries and are classified as subtalar AR and calcaneo-stop (CS).

AIM

We investigated the literature published in the last 5 years with the aim of providing an update on the evidence related to AR treatment in FFF patients. We report the principal findings of subtalar AR and CS procedures concerning clinical and radiological outcomes and complication rates in the general population, young athletes, and obese people according to material device.

METHODS

Following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic review of studies published in the past 5 years and included the PubMed and Science Direct databases was performed on May 6, 2020. The research string used was (pediatric OR children OR Juvenile NOT adult) AND (flexible NOT rigid) AND (flat foot OR pes planus) AND (calcaneo-Stop OR arthroereisis OR subtalar extra-articular screw OR SESA OR subtalar arthroereisis OR endosinotarsal). The risk of bias assessment was performed using the Dutch checklist form for prognosis.

RESULTS

A total of 47 articles were found. Ultimately, after reading the full text and checking reference lists, we selected 17 articles that met the inclusion and exclusion criteria. A total of 1864 FFFs were identified. Eight studies concerned the subtalar AR (47.1%) and nine concerning CS (52.9%). The average age of patients at start of treatment was 11.8 years, the average follow-up of the studies was 71.9 mo (range 29.1-130). Globally, complications occurred in 153 of the 1864 FFF treated, with a rate of 8.2%.

CONCLUSION

Both AR procedures are valid surgical techniques for treating FFF. Surgeon experience, implant cost, and cosmetic correction are the most common considerations included in the orthopedic device decision-making process. In obese patients, the subtalar AR is not recommended. In adolescents who need to improve sports performance, the CS screw had better results compared with other implants.

Subtalar Arthroereisis for Flexible Flatfoot in Children-Clinical, Radiographic and Pedobarographic Outcome Comparing Three Different Methods

Subtalar arthroereises (STA) is a minimally invasive and reversible surgery to correct symptomatic flexible flatfoot (FFF) in children. Various techniques were described either applying expandable sinus tarsi implants or lateral calcaneus stop screws. Studies comparing the outcome of STA with different devices are rare. This retrospective single-center cohort study analyzes the results of STA using three different implants. 113 STA were performed in 73 consecutive patients (28 females). Mean age at surgery was 10.8 years (range 5-16). Mean follow-up was 29.0 months (range 1-111). In 21 feet the non-absorbable Kalix^® endorthesis and in 56 feet the absorbable Giannini endorthesis were applied. Subtalar extraarticular screw arthroereises (SESA) was conducted in 36 feet. Clinical, radiographic and pedobarographic parameters were analyzed. No intraoperative complications were observed. All three procedures achieved comparable improvements of the clinical, radiographic and pedobarographic parameters. The mean foot function index (FFI) improved from 36.4 (range 12-63) to 22.8 (range 2-55). The mean preoperative calcaneal inclination angle and the lateral talocalcaneal angle improved from 9.5° (range 0-22) and 42.3° (range 21-62) to 12.8° (range 0-26) and 37.6° (range 15-56), respectively. Pedobarographically determined values of the arch index, the medial midfoot contact area and the medial forefoot peak pressure decreased. In contrast to SESA (1/36, 3%), a higher incidence of implant-related complications was observed using Kalix^® (6/21, 29%) and Giannini (10/56, 8%) sinus tarsi implants. Peroneal muscle contractures only occurred in the SESA group (4/36, 11%). Premature removal due to treatment-related complications was necessary in 6/21 Kalix^® implants (29%), 4/56 Giannini implants (7%) and 4/36 SESA implants (11%). Implant choice for treatment of painful FFF in children with STA seems to play a subordinate role. Clinical, radiographic and pedobarographic outcomes are comparable between the applied implants. Surgeons and patients should be aware of the different spectrum of implant-related complications. Treatment can be reliably monitored by radiation-free pedobarography providing dynamic information about the deformity.

Functional and radiographic comparison of subtalar arthroereisis and lateral calcaneal lengthening in the surgical treatment of flexible flatfoot in children

PURPOSE

One of the most widespread diseases of children's orthopaedic problems is flatfoot. If conservative therapy failed, surgical treatment would be indicated. Lateral calcaneal lengthening (LCL) and subtalar arthroereisis (SA) are two types of operations used to correct symptomatic flexible flatfoot (FFF). The purpose of this study is to compare the functional and radiographic features of these two surgical procedures.

PATIENTS AND METHODS

In this prospective randomized clinical trial study, we recruited 66 patients between 2018 and 2019. For clinical assessment, American Orthopedics Foot and Ankle Society (AOFAS), visual analog scale (VAS), subtalar motion, presence of medial longitudinal arch, and family satisfaction were measured. Evaluation of radiographic angles was based on AP (AP Tal-1Met) and Lat (Lat Tal-1Met) view of Talus-1st metatarsal angle (Meary's angle) and calcaneal pitch.

RESULT

There was no significant difference between the two types of surgery regarding Lat Tal-1Met and AP Tal-1Met. The significantly larger angle in the LCL group was calcaneal pitch (P value < 0.001). AOFAS significantly increased from 68.71 ± 5.70 to 87.87 ± 7.14 (P value < 0.001) and from 67.28 ± 6.01 to 86.14 ± 7.56 (P value < 0.001) in LCL and SA respectively. Family satisfaction was significantly higher in the SA (8.14 ± 0.97) comparing to LCL (7.29 ± 0.86) at the latest follow-up (P value < 0.001).

CONCLUSION

While both groups have substantial improvement in clinical and radiographic aspects, the SA technique is less-invasive, rapid symptom relief, and has early weight-bearing capacity.

TRIAL REGISTRATION

IRCT20180823040853N1.

Subtalar arthroereisis for the treatment of the symptomatic paediatric flexible pes planus: a systematic review

Subtalar arthroereisis has a controversial history and has previously been associated with high failure rates and excessive complications.A database search for outcomes of arthroereisis for the treatment of symptomatic paediatric flexible pes planus provided 24 articles which were included in this review, with a total of 2550 feet operated on.Post-operative patient-reported outcome measures recorded marked improvement. Patient satisfaction was reported as excellent in 79.9%, and poor in 5.3%. All radiological measurements demonstrated improvement towards the normal range following arthroereisis, as did hindfoot valgus, supination, dorsiflexion and Viladot grade.Complications were reported in 7.1% of cases, with a reoperation rate of 3.1%.Arthroereisis as a treatment for symptomatic paediatric flexible pes planus produces favourable outcomes and high patient satisfaction rates with a reasonable risk profile. There is still a great deal of negativity and literature highlighting the complications and failures of arthroereisis, especially for older implants.The biggest flaws in the collective literature are the lack of high-quality prospective studies, a paucity of long-term data and the heterogeneity of utilized outcome measures between studies. Cite this article: EFORT Open Rev 2021;6:118-129. DOI: 10.1302/2058-5241.6.200076.

Surgical Treatment of Severe Idiopathic Flexible Flatfoot by Evans-Mosca Technique in Adolescent Patients: A Long-Term Follow-Up Study

Flexible idiopathic flatfoot is very common in growing age and rarely causes pain or disability. Surgery is indicated only in severe symptomatic cases that are resistant to conservative treatment, and numerous surgical procedures have been proposed. Lateral column calcaneal lengthening as described by Evans and modified by Mosca is a widely used surgical technique for the correction of severe symptomatic flexible flatfoot. In the present study, we report the long-term clinical and radiographic results in 14 adolescent patients (mean age: 12.8 years) affected by severe symptomatic flexible flatfoot, surgically treated by Evans–Mosca procedure, for a total of 26 treated feet (12 cases bilateral and 2 unilateral). In all cases, surgery was indicated for the presence of significant symptoms resistant to nonsurgical management. Clinical evaluation was made according to the American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale, the Foot and Ankle Disability Index (FADI) Score, and Yoo et al.'s criteria. Radiographic evaluation was made using anteroposterior and lateral weight-bearing radiographs of the feet to evaluate Meary's angle and Costa–Bertani's angle and to evaluate possible osteoarthritic changes in the midtarsal joints. At follow-up (mean: 7 years and 7 months), we observed a satisfactory result in all patients. The mean average score of the AOFAS Ankle-Hindfoot Scale improved from 60.03 points to 95.26; the mean FADI score improved from 71.41 to 97.44; and according to Yoo et al.'s criteria, the average clinical outcome score was 10.96. At radiographic examination, nonunion of the calcaneal osteotomy was never observed. Meary's angle improved from an average preoperative value of 25° to 1.38° at follow-up; Costa–Bertani's angle improved from an average preoperative value of 154.2° to 130.9° at follow-up. In no case, significant radiographic signs of midtarsal joint arthritis were observed. According to our results, we believe that Evans–Mosca technique is a valid option of surgical treatment for severe idiopathic flexible flatfoot and allows a satisfactory correction of the deformity with a low rate of complications.

Long-term results of subtalar arthroereisis for the treatment of symptomatic flexible flatfoot in children: an average fifteen year follow-up study

AIM OF THE STUDY

The aim of this study is to report the long-term outcomes of a homogenous series of patients who underwent subtalar arthroereisis (STA) for the treatment of symptomatic flexible flatfoot (FFF).

METHODS

Thirty-four pediatric patients who underwent STA with a bioabsorbable implant were enrolled and radiographic measurements, clinical outcomes, and patients' satisfaction were evaluated.

RESULTS

At a mean 180 months follow-up, radiographic measurements showed significant improvement. A physiological footprint and a proper hindfoot alignment were shown in more than 70% of patients. Mean AOFAS score was 90.4 ± 9.2 (72-100), mean SF-12 was 44.7 with 30 out of 34 patients (88.2%) satisfied with the procedure.

CONCLUSION

STA with a bioabsorbable implant showed satisfactory long-term results. Based on the data subgroup analysis, nine to 11.5 years for female and nine to 13.5 years for male appeared to be the most appropriate age for surgery.

PEDIATRIC FLEXIBLE VALGUS FLATFOOT CORRECTION BY ARTHROEREISIS

Objective:

This article aimed to evaluate the efficacy of arthroereisis using synthetic polyethylene implants to correct excessive valgus deformity in pediatric patients with flexible valgus flatfoot.

Methods:

Retrospective study of 20 pediatric patients with flexible valgus flatfoot, totaling 23 feet, between five and 14 years old, operated between January 2009 and July 2016. Clinical evaluations were performed by the Valenti podoscopic classification and the American Orthopaedic Foot & Ankle Society criteria, based on radiographic images and podoscopic analysis. These patients underwent surgical treatment with the introduction of a synthetic implant in the sinus tarsi. Multiple linear regression analysis with Backward selection of variables, angles of pre and postoperative of radiographic images of the patients submitted to arthroereisis were performed.

Results:

The arthroereisis with interposition of synthetic material was satisfactory, considering that 91% of the cases presented clinical and radiographic improvement, with correction of angles and improvement in deformity degrees. Two cases presented implant loosening. The variables of the Bordelon and Pitch angles significantly influenced (p < 0,05) the improvement of the correction of deformity degrees.

Conclusion:

The arthroereisis with the interposition of synthetic polyethylene material showed to be an effective technique for flexible flatfoot in symptomatic pediatric patients. Level of Evidence II, Prognostic studies - Investigating the Effect of a Patient Characteristic on the Outcome of Disease.

Body Weight Effects on Extra-Osseous Subtalar Arthroereisis

Implant extrusion in subtalar arthroereisis is a common complication for pediatric flexible flatfoot. However, there were a limited number of articles addressing the body weight effects on implant extrusion after the procedure. We conducted a 24-month follow-up assessment after subtalar arthroereisis. Surgical patients who underwent the Vulpius procedure were retrospectively collected from May 2010 to January 2017, including 59 cases of both feet having implants in situ and 43 cases of both feet having implant extrusion. The average age of 102 patients was 9 years old. The mean body mass index (BMI) of the implant in situ group was 19.5, whilst the extrusion group was 21.2 (p = 0.035). The inter-observer correlation was excellent. There were 11 cases (39.3%) of bilateral extrusion in the overweight group (BMI ≥ 24) and 13 cases (23.2%) in the low body weight group (BMI ≤ 18.5) (p < 0.0004). Postoperative radiographic angles were corrected in both the implant in situ group and the extrusion group. Nonetheless, the implant in situ group revealed better postoperative outcomes of Meary’s angle and the talonavicular angle from an anterior-posterior view, and the talar inclination angle from a lateral view. We conclude that a higher BMI is related to implant extrusion and worse results after subtalar arthroereisis. Further prospective study to investigate whether preoperative weight loss results in improved surgical outcomes is warranted in the future.

Patient-perceived outcomes after subtalar arthroereisis with bioabsorbable implants for flexible flatfoot in growing age: a 4-year follow-up study

PURPOSE

Results of subtalar arthroereisis in flexible flatfoot have been mainly reported in the literature using clinical or radiographical findings. However, the aim of this study is to evaluate the patient-perceived quality of life using self-reported questionnaires after subtalar arthroereisis using a bioabsorbable implant.

METHODS

Italian modified FFI and the SEFAS scores were submitted to a consecutive series of 173 patients who underwent surgical treatment for flatfoot deformity using a bioabsorbable endo-orthotic implant. Postoperative complication rates were assessed. Time needed to resume normal sports activities was recorded.

RESULTS

Mean population age was 11.2 years with slight variability between males and females. At a mean follow-up of 4 years, arthroereisis with bioabsorbable implants showed excellent results for the perception of the quality of life with an average result for FFI score of 4.5 and an average SEFAS score of 47.19. Time needed to resume sport activities was 4.7 months ± 0.2 with almost no difference between the groups. Four patients needed a second procedure for implant removal.

CONCLUSION

Arthroereisis using a bioabsorbable implant offers good results in terms of satisfaction and quality of life with a negligible rate of failures and patient complaints based on self-reported questionnaires. The patient reported high degrees of satisfaction, and their quality of life was not compromised at all by the procedure.