Fixation of Mitchell's osteotomy with bioabsorbable pins for treatment of hallux valgus deformity

Tratamiento del hallux valgus rigidus con osteotomía tipo Mitchell modificada. Descripción de la técnica quirúrgica y evaluación funcional a mediano plazo

Objetivo: Describir la técnica quirúrgica de Mitchell modificada para el tratamiento del hallux valgus rigidus grado 2, y evaluar los resultados a mediano plazo. Materiales y Métodos: Estudio prospectivo observacional. Entre agosto de 2015 y enero de 2019, 21 pacientes (23 pies) con hallux valgus rigidus grado 2 fueron sometidos a una osteotomía tipo Mitchell modificada. Resultados: Se comunican los resultados sobre la base de la edad, el sexo, el seguimiento posoperatorio, el puntaje de la AOFAS, el pie afectado, la pérdida de reducción, el colapso de la cabeza del metatarsiano, el dolor residual y la necesidad de plantillado para el alta. El puntaje de la AOFAS a los 18 meses fue de 94,78. Los pacientes retornaron a su actividad laboral, en promedio, a los 16.6 días y a sus actividades previas, a los 3.43 meses. Conclusión: Presentamos una técnica quirúrgica que combina los beneficios de la osteotomía de Chevron y la de Mitchell, con excelentes resultados clínicos y funcionales.

Modified scarf osteotomy for hallux valgus: From a finite element model to clinical results

PURPOSE

Finite element (FE) analysis and clinical follow-up were used to evaluate the efficacy of modified scarf osteotomy for moderate-to-severe hallux valgus (HV).

METHOD

We retrospectively evaluated 42 patients (44 feet) who underwent modified rotational scarf osteotomy for moderate-to-severe HV at our institution between January 2010 and January 2019. Radiological indicators and subjective scores were recorded at different time points. To compare the results and elemental characteristics, a FE model of the metatarsophalangeal (MTP) joint that included anatomically realistic geometrical and structural characteristics was built. The biomechanical features and correction differences in dynamic loads as well as the incidence of troughing were estimated.

RESULTS

Both the hallux valgus angle (HVA) and intermetatarsal angle (IMA) showed significant improvement 6 weeks postoperatively (p < 0.05); additionally, the HVA increased from 6 weeks postoperatively to the last follow-up, while the IMA showed no significant changes (p > 0.05). The subjective scores significantly improved from the preoperative period to the last follow-up. The percentages of troughing and recurrence were remarkably low in our pilot study because of the innate stability of the modified rotated fixation.

CONCLUSION

Our preliminary findings suggest that modified rotational scarf osteotomy offers sufficient stability, correct HV deformity effectively, and good clinical outcomes for moderate to severe HV.

Bioabsorbable implants in forefoot surgery: a review of materials, possibilities and disadvantages

Bioabsorbable and biodegradable implants offer new possibilities in orthopaedic and trauma surgery. As soon as the initial stability of the degradable implants has reached the qualities of conventional materials, new devices may find usage in younger and more demanding patients. Residual conventional osteosynthetic material or the necessity to remove metal increasingly seems to be more of an adverse event than daily practice in forefoot surgery. Nevertheless, some drawbacks need to be discussed. Recent literature screened for the use of bioabsorbable and biodegradable materials in forefoot surgery, available implants and indications in forefoot surgery were analysed and summarized. Apart from common indications in forefoot surgery, points of interest were the type of biomaterial, the process of biodegradation and biointegration, and possible adverse events. Materials were comprehensively discussed for each indication based on the available literature. Polylactide, polyglycoside and polydioxanone are considered safe and sufficiently stable for use in forefoot surgery. Low complication rates (e.g. 0.7% for pin fixation in hallux deformities) are given. Magnesium implants suffered from an extensive corrosive process in the first generation but now seem to be safe in forefoot surgery and offer good options compared with conventional titanium screws, especially in procedures of the first ray. Allograft bone has proven feasibility in small case series, but still lacks larger or randomized clinical trials. The first results are promising. Bioresorbable and osseointegrating devices offer attractive new possibilities for surgeons and patients. Despite all the known advantages, the difficulties and possible complications must not be forgotten, such as soft tissue reactions, unwanted osteolysis and a lower primary mechanical load capacity.

Cite this article: EFORT Open Rev 2021;6:1132-1139. DOI: 10.1302/2058-5241.6.200157

Modified Mitchell technique for treating hallux valgus: Retrospective case series on a Middle-Eastern population and literature review

Introduction

The hallux valgus deformity is a complex deformity of the first ray of the foot, with more than 100 procedures developed for its treatment. The aim of this retrospective study was to assess the clinical and radiographic outcomes of a modified Mitchell's technique.

Methods

Between 2007 and 2018, 75 patients underwent the procedure. Clinical results were assessed by the AOFAS score. Radiological studies were evaluated by measuring pre-operative and post-operative HVA and IMA angles as well as the relative shortening of the first metatarsal.

Results

Of the initial 75 patients, 42 patients remained eligible with a total of 67 feet. The mean age and follow-up were 47.8 and 5.2 years respectively. Global AOFAS score improved from 45.3 to 88.8 (p < 0.01). Mean HVA and IMA improved from 37.0 to 10.2 (p < 0,01) and 12.1 to 5.6 (p < 0.01), respectively. The mean metatarsal shortening was 3.0 mm (p < 0.01). The statistical analysis showed no significant correlation between preoperative HVA and IMA angles with postoperative shortening, metatarsalgia, AOFAS scores nor the difference between the preoperative and postoperative AOFAS scores.

Conclusion

Short- and long-term outcomes of this modified Mitchell's osteotomy have been reported. Compared to other studies, these modifications proved to result in very good clinical and radiological outcomes even in severe cases with HVA>40. It has shown to be reliable, reproducible, and cost-efficient with low complication rates. We would like to highlight the importance of proper patient selection, limited soft tissue stripping, and adherence to the proposed surgical steps to avoid unwanted complications.

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The Modified Mitchell Technique has been shown to be reliable, reproducible, and cost-efficient with low complication rates.

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The addition of intra-articular lateral soft tissue release, preventing a lateral incision, decreasing wound and soft tissue complications.

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The use of autologous bone graft adjacent to the osteotomy stump helps improve union.

The effect of hallux valgus open and percutaneous surgery on AOFAS scale: a systematic review and meta-analysis

PURPOSE

To estimate the comparative effect of open and percutaneous hallux valgus (HV) surgery on patients' quality of life (QoL) using the American Orthopedic Foot and Ankle Society (AOFAS) scale including total score and individual domains (pain, function, and alignment).

METHODS

MEDLINE, EMBASE, Cochrane Library, and Web of Science databases were systematically searched from inception to March 2020 for studies on the effect of HV surgery on patients' QoL using the AOFAS score. A standardized mean difference score was calculated on the total AOFAS score and on each AOFAS domain (pain, function, and alignment) using Cohen's d index.

RESULTS

Considering the 53 published studies included, the pooled effect size (ES) estimates for the AOFAS total score were 3.69 (95% CI 3.37-4.01; I² = 95.5%) for open surgery and 3.40 (95% CI 2.99-3.80, I² = 88.2%) for percutaneous surgery. The total pooled ES estimate was 3.61 (95% CI 3.35-3.87, I² = 94.5%). Considering the pain domain, the pooled ES estimates were 2.21 (95% CI 1.98-2.43, I² = 64%) for open surgery and 2.52 (95% CI 1.83-3.20, I² = 92.6%) for percutaneous surgery. For the function domain, the pooled ES estimates were 1.37 (95% CI 0.93-1.81, I² = 91%) for open surgery and 2.28 (95% CI 1.10-3.47, I² = 96.8%) for percutaneous surgery. Finally, the pooled ES estimates for the alignment domain were 3.99 (95% CI 3.51-4.47, I² = 85.7%) for open surgery and 2.66 (95% CI 2.23-3.09, I² = 78.5%) for percutaneous surgery.

CONCLUSION

Our data support that HV surgery increases the total AOFAS score as well as the AOFAS scores by domain (pain, function, and alignment). Furthermore, our data show that HV surgery increases patients' QoL, after both open and percutaneous surgery, without differences between them.

Mitchell's osteotomy augmented with bio-absorbable pins for the treatment of hallux valgus: A comparative finite element study

BACKGROUND

There is an inadequacy of conventional means to assess the surgical outcomes of a bunion surgery. We used the Finite Element Analysis for evaluating the typical Mitchell's procedure outcomes with or without bio-absorbable pins.

METHODS

We developed a 3D FE model based on the CT images of a female volunteer with hallux valgus. A typical procedure was simulated on the foot model and two pins were virtually inserted for enhancing the fixation. We validated our model by comparing the predicted pressure results with the plantar pressure measured by a specific platform.

RESULTS

The comparison of the plantar pressure distribution revealed similar patterns. A greater displacement was observed on the medial side of the osteotomy, but it was decreased after using pins. The maximum average pressure under the 1^st metatarsal head was decreased after the osteotomy. The respective pressure under the 3^rd and 5^th metatarsal head was decreased more after using pins, while, under the 2^nd and 4^th metatarsal head, an increase was developed.

CONCLUSION

The use of pins had no significant influence on the healing process but gave additional stability inside the osteotomy and could be used in cases where enhancement is needed. The surgeon should be familiar with the expected stress rising to the other metatarsal, considering the concomitant pathology or the additional interventions that should be performed.

Percutaneous forefoot surgery for treatment of hallux valgus deformity: an intermediate prospective study

BACKGROUND

This study aims to illustrate the results of percutaneous forefoot surgery (PFS) for correction of hallux valgus.

MATERIALS AND METHODS

A prospective study of 108 patients, with hallux valgus deformity, who underwent PFS was conducted. The minimum clinical and radiological follow-up was two years (mean 57.3 months, range 22-112).

RESULTS

Preoperative mean visual analog scale was 6.3 ± 1.5 points, and AOFAS scores were 50.6 ± 11 points. At the last follow-up, both scores improved to 1.9 ± 2.4 points and 85.9 ± 1.83 points, respectively. Mean hallux valgus angle changed from 34.3° ± 9.3° preoperatively to 22.5° ± 11.1° at follow-up. At follow-up, 76.5% of the subjects were satisfied or very satisfied. Recurrence of medial 1st MT head pain happened in 22 cases (16.7%).

CONCLUSIONS

PFS, in our study, does not improve the radiological and patient satisfaction rate results compared with conventional procedures. The main advantage is a low postoperative pain level, but with an insufficient HVA correction.

LEVEL OF EVIDENCE

II, prospective study.

Prospective randomized study of chevron osteotomy versus Mitchell's osteotomy in hallux valgus

BACKGROUND

We conducted a prospective randomized trial to compare the most popular osteotomy types of operative treatment of hallux valgus (HV) used in Norway, Mitchell's osteotomy (MO) and chevron osteotomy (CO).

METHODS

One hundred twenty adult female patients were prospectively randomized to treatment with either MO or CO. All operative procedures were performed with ankle block and with tourniquet applied. None of the patients received any antibiotic or antithrombotic prophylaxis. The follow-up period was 3 years. Clinical results were rated according to the American Orthopaedic Foot and Ankle Society (AOFAS) Clinical Rating System (CRS).

RESULTS

HV in the MO group was reduced from 30 (range, 20 to 44) to 15 (range, 8 to 24) degrees and IM angle from 11 (range, 6 to 14) to 7 (range, 4 to 11) degrees. HV in the CO group was reduced from 31 (range, 22 to 42) to 16 (range, 6 to 24) degrees and IM angle from 14 (range, 8 to 20) to 6 (range, 2 to 10) degrees. Transfer metatarsalgia occurred in 36 (60%) patients and hammertoe in 6 (10%) patients in the MO group. In the CO group, metatarsalgia occurred in 5 patients. The median loss of postoperative HV correction was 4 (range, 2 to 10) degrees in mild deformity and 6 (6 to 10) degrees in moderate deformity.

CONCLUSION

Patients treated with CO had significantly better results for AOFAS CRS, number of postoperative complications, patient satisfaction, and length of sick leave for the employed patients. Based on our results, we consider that in female patients CO should be regarded as the first-line procedure for treatment of mild and moderate HV.

LEVEL OF EVIDENCE

Level I, prospective randomized study.

Proximal opening wedge metatarsal osteotomy for correction of moderate to severe hallux valgus deformity using a locking plate

PURPOSE

Hallux valgus is a complex deformity of the first metatarsophalangeal joint, with varus angulation of the first metatarsal, valgus deviation of the great toe and lateral displacement of the sesamoids and the extensor tendons. The aim of the surgery is to achieve correction of the varus deviation of the 1st metatarsal which is considered by some as the primary intrinsic predisposing factor to hallux valgus deformity.

METHODS

We retrospectively reviewed 85 patients (107 feet) who underwent an opening wedge osteotomy of the 1st metatarsal for correction of moderate to severe hallux valgus and metatarsus primus varus. A medially applied anatomic pre-contoured locking plate was used for fixation of the osteotomy.

RESULTS

The mean IMA was decreased from 15.8 (range 12-22) degrees to 7.8 (range 0-12) degrees. The mean pre-operative HVA was 39 (range 21-52) degrees and the mean postoperative HVA was 11.8 (6-19) degrees. The pre-operative AOFAS score was 52 (SD 3.1) and the postoperative score was 85 (SD 5.2).

CONCLUSION

The proximal opening wedge metatarsal osteotomy is a safe, effective and reproducible technique for correction of moderate to severe hallux valgus deformity. The use of a locking plate provides enough control at the fragments, enhancing healing of osteotomy and maintenance of the correction even with a violated proximal lateral cortex.

A minimally invasive technique for surgical treatment of hallux valgus: simple, effective, rapid, inexpensive (SERI)

PURPOSE

Several bony and soft tissue procedures have been described for the treatment of hallux valgus, and currently mini-invasive surgical techniques are preferred in order to reduce surgical trauma, complications, time of surgery and to allow an earlier recovery. The aim of this study is to analyse a series of 1,000 consecutive cases of hallux valgus, surgically treated by the minimally invasive SERI technique, reporting results at mid-term follow-up.

METHODS

We prospectively studied 641 patients (1,000 feet) with symptomatic hallux valgus surgically treated by SERI osteotomy. Inclusion criteria were: age between 20 and 65 years, reducible mild or moderate hallux valgus, HVA ≤ 40°, IMA ≤ 20°, and arthritis of the first metatarsophalangeal joint up to grade 2 according to the Regnauld classification.

RESULTS

The American Orthopaedic Foot and Ankle Society (AOFAS) score rose from 46.8 ±  6.7 preoperatively to 89 ± 10.3 at last follow-up. Radiographic control at follow-up showed a complete healing of the osteotomy and remodelling of the metatarsal bone. Low rate of complication has been reported.

CONCLUSIONS

This study demonstrated that the SERI technique is effective in treating mild to moderate hallux valgus in terms of relief from symptoms and functional improvement. This technique allowed correction of the main parameters of the deformity, with durable clinical and radiographic results at a mid-term follow-up.

Long-term results of the retrocapital metatarsal percutaneous osteotomy for hallux valgus

PURPOSE

The current trend in hallux valgus surgery is directed toward percutaneous procedures. However, no evidence that any of these methods of treatment are superior to the others has been described, excepting studies in the long term. The aim of this study was to analyse a series of patients who had undergone a percutaneous distal retrocapital osteotomy of the first metatarsal, and had been followed up for ten years.

METHODS

We carried out a clinical and radiological evaluation of 115 feet ten years after surgery.

RESULTS

The AOFAS scale results in the tenth postoperative year remained significantly favourable compared to their corresponding values in the preoperative period, yielding an improvement of 42.2 points overall on average. In relation to radiological findings, the mean hallux angle was maintained below 20 °, with a mean intermetatarsal angle of 8.1 °.

CONCLUSION

Percutaneous retrocapital metatarsal osteotomy for treatment of mild to moderate hallux valgus is effective in the long term, with the advantages of a minimally invasive procedure.

Mid-term results of Scarf osteotomy in hallux valgus

We performed a retrospective study on 178 Scarf osteotomies with a mean follow-up of 44.9 months (range 15-83 months). Clinical rating was based on the forefoot score of the American Orthopaedic Foot and Ankle Society (AOFAS). Weight bearing X-rays were used to perform angular measurements and assess the first metatarsophalangeal joint (MTP 1). At follow-up the mean AOFAS score had improved significantly (p < 0.001), but only 55% of the feet showed a perfect realignment of the first ray. Patients with a hallux valgus angle exceeding 30° and pre-existing degenerative changes at the MTP 1 joint displayed inferior clinical results (p < 0.05). Nearly 20% of the patients suffered from pain at the MTP 1 joint. This was clearly attributed to an onset or worsening of distinct radiographic signs of arthritis (p < 0.05) resulting in painfully decreased joint motion. Comparing radiographic appearance three months postoperatively and at follow-up, we found that radiographic criteria (hallux valgus, first intermetatarsal angle, hallux valgus interphalangeus, MTP 1 joint congruency, arthritic lesions at MTP 1) worsened with time.