Learning curve in relation to radiation exposure, procedure duration and complications rate for Minimally Invasive Chevron Akin (MICA) osteotomy

The Learning Curve in Hallux Valgus Surgery

For any surgical technique, the learning curve is the number of times a particular procedure must be undertaken in order to complete it repeatedly with high accuracy and proficiency. Scientifically, a difficult task to master is represented by a flat learning curve, as the steep portion of the learning curve would correlate with rapid learning. Today, there's more literature on the learning curve of percutaneous HV surgery than on any other procedure in foot and ankle surgery. Due to the lack of conclusive research on traditional HV techniques, no comparison to modern percutaneous techniques is possible. The current literature suggests that it takes between 30-40 cases to gain sufficient proficiency in 3rd generation percutaneous hallux valgus correction.

A Multi-Dimensional Systematic Review of Minimally Invasive Bunion Surgery (MIBS)

Background/Objectives: Hallux valgus, or a bunion, is a prevalent foot deformity associated with pain, limited mobility, and reduced quality of life. Surgical treatments include minimally invasive and traditional open techniques, but the optimal approach remains debated. This systematic review evaluates long-term outcomes, patient satisfaction, cost-effectiveness, the influence of patient-specific factors, rehabilitation protocols, and complication rates for these methods. Methods: A comprehensive search of PubMed, Medline, EMBASE, and Cochrane databases identified 22 studies published within the last 15 years, each with a minimum follow-up of 2 years. The systematic review adhered to PRISMA-ScR guidelines. Eligible studies reported on at least one of six key outcomes, and data were extracted on radiographic and clinical results, patient satisfaction, costs, rehabilitation timelines, and adverse events. Results: Minimally invasive bunion surgery (MIBS) showed faster recovery, higher patient satisfaction, and improved quality of life compared to open surgery. Radiographic outcomes, including hallux valgus and intermetatarsal angle correction, were durable, though outcomes were less consistent for severe deformities. MIBS was more cost-effective over time, owing to shorter operating times and faster recovery. Rehabilitation was accelerated, and wound complications were fewer with MIBS. However, open techniques remained preferable for severe deformities due to their reliability in complex corrections. Conclusions: MIBS offers substantial advantages for most patients undergoing bunion surgery, including faster recovery and fewer complications. However, open techniques may be better suited for severe deformities. Further research is needed to refine patient selection criteria and evaluate long-term outcomes in diverse populations.

Short-term results of minimally invasive surgery using a 3D-printed guide for the treatment of hallux valgus

INTRODUCTION

Minimally invasive surgery (MIS) is often used to treat hallux valgus deformities, as it is associated with few wound complications and shorter recovery times. Minimally invasive chevron osteotomy and Akin osteotomy (MICA) is a common minimally invasive treatment for HV. However, effective correction of hallux valgus and precise screw placement during MIS are difficult. The aim of this study was to introduce and evaluate the clinical and radiographic effectiveness of a novel MIS technique involving the use of a 3D-printed guide for hallux valgus.

MATERIALS AND METHODS

We retrospectively studied the results of MIS with a 3D-printed guide plate for symptomatic hallux valgus from May 2022 to December 2023. The preoperative and postoperative hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), first metatarsal pronation angle (M1PA), tibial sesamoid position (TSP), forefoot width, visual analogue scale (VAS) score, AOFAS Hallux MTP-IP score, and the number of intraoperative fluoroscopy were measured.

RESULTS

A total of 22 feet in 19 patients were included in the study. There were 15 women and 4 men with an average age of 38.0 y (range 16-61). The preoperative HVA, IMA, DMAA and M1PA were 30.3 ± 10.7°, 13.9 ± 2.8°, 8.3 ± 2.9° and 16.3 ± 6.5°, respectively. The postoperative HVA, IMA, DMAA and M1PA were 10.7 ± 4.1°, 5.7 ± 1.8°, 2.3 ± 1.7° and 3.5 ± 2.1°, respectively. The forefoot width decreased from 92.1 ± 5.5 mm to 85.6 ± 5.4 mm on average. The VAS and TSP ranged from 4.4 ± 0.9 and 4.9 ± 0.8 to 0.3 ± 0.6 and 2.0 ± 1.1, respectively. The AOFAS Hallux MTP-IP scores improved from 59.1 ± 10.7 to 94.8 ± 5.7 on average. The average number of fluoroscopy shots during operation were 34 times (range 30 to 38).

CONCLUSIONS

A 3D printed guide technique can be beneficial for precise positioning of the first metatarsal head, enhancing the accuracy of screw placement, and reducing radiation exposure.

The Learning Curve of Reverdin-Isham and Akin Percutaneous Osteotomies for Hallux Valgus Correction: A Bayesian Approach

Background/Objectives: Assessing the learning curve is essential for surgical techniques that require precision and technical adaptation. Although modified Reverdin-Isham and Akin percutaneous osteotomies (RIAOs) are well-established procedures for the treatment of hallux valgus (HV), their percutaneous nature and specific technical demands justify the evaluation of the learning curve. Therefore, this study aimed to assess the learning curve of RIAOs for the HV correction, using for the first time a Bayesian approach. Methods: Modified RIAOs were applied to treat mild-to-moderate HV in patients who were prospectively enrolled. The hallux valgus angle (HVA), inter-metatarsal angle (IMA), distal metatarsal articular angle (DMAA) and tibial sesamoid position were assessed. Clinical outcomes were evaluated with the American Orthopaedic Foot & Ankle Society (AOFAS) Scale, Visual Analog Scale (VAS) and Numerical Rating Scale (NRS). Surgery and fluoroscopy times were recorded. To evaluate the learning curve, a Bayesian analysis using a change point model was performed. Results: Analysis of 142 patients revealed three distinct phases in the learning curve, with a plateau reached after 112 procedures. Over time, the mean operation duration decreased from 55 to 27 min, and fluoroscopy time decreased from 60 to 28 s. Conclusions: A flexible change point model was used to model a learning curve, guaranteeing a robust interpretation of the data. The correction of the HV angles showed similar results in the three phases of the curve, demonstrating that the surgeon achieved positive results from the beginning of the surgery.

Percutaneous calcaneal sliding osteotomy with the rising sun technique

BACKGROUND

Calcaneal slide osteotomies represent a well-established component in the surgical treatment of joint-preserving hind foot corrections. The percutaneous technique aims to minimize the surgical morbidity and maximize surgical efficiency. There is a consensus that percutaneous calcaneal sliding osteotomy (PCSO), using a low-speed and hightorque burr, is generally performed in four steps corresponding to the four quadrants of the cross-section of the calcaneal tuber. We present a technique that allows a more efficient osteotomy by cutting the far cortex in one step using standard percutaneous equipment. The aim of this study is to present preliminary results and the surgical technique of a modification for percutaneous calcaneal sliding osteotomy.

MATERIALS AND METHODS

Between June 2016 and March 2023, a total of 101 percutaneous calcaneal slide osteotomies were performed using the Rising Sun Technique. Prospective clinical and radiologic evaluation was completed for 70/101 cases (69.3%). Complications were classified according to the modified Clavien-Dindo-Sink Classification (CDS I-III). For the last 25 cases, additional information on surgery duration and use of fluoroscopy was available. The results of two surgeons (S1, S2) with different MIS experiences were compared to determine surgical proficiency.

RESULTS

The mean follow-up was 36 months (range 12-73 months). In 46 cases the underlying deformity was a planovalgus and in 24 a cavovarus deformity. In total, there were 5/70 (7.1%) surgery-related complications, three cases needed revision surgery: 2 patients required superficial surgical wound revision for disturbed wound healing, 1 patient requested screw removal due to discomfort related to the hardware after 15 months. The mean surgery duration for both surgeons combined was 19.6 min, and the average number of fluoroscopies was 20.2.

CONCLUSIONS

Compared to traditional open calcaneal slide osteotomies, PCSO helps to reduce softtissue morbidity and may result in fewer surgery-related complications. The Rising Sun procedure of PCSO represents a safe and easy-to-perform alternative to the traditional 4-quadrants technique in the percutaneous correction of hindfoot malalignment. Our prospective case series showed a low rate of complications and reproducible surgery time and use of fluoroscopy.

Evaluating the learning curve of Minimally Invasive Chevron and Akin Osteotomy for correction of hallux valgus deformity: a systematic review

BACKGROUND

One procedure that has gained popularity in the surgical management of hallux valgus is the minimally invasive Chevron and Akin osteotomy (MICA). The purpose of this systematic review was to evaluate the learning curve associated with this technically demanding procedure.

METHODS

A search of the EMBASE and PubMed databases was performed to identify all clinical studies that assessed the learning curve associated with the MICA procedure. Studies where patients were not diagnosed with hallux valgus, did not undergo MICA, or did not report data on operation time, fluoroscopy exposure, or complications were excluded. A risk of bias assessment was conducted to assess the validity of the studies.

RESULTS

The initial literature search yielded 287 studies, and seven studies were included in the final analysis. A quantitative comparative analysis could not be performed as the included studies used different statistical methods to quantify the learning curve. Lewis et al. determined that after 38 operations, there was a decrease in operation time and fluoroscopy exposure (p < .001). Merc et al. found that it took 29 and 30 operations to reach a plateau for operation time and fluoroscopy exposure, respectively (p < .001). Palmanovich et al. found that it took 20 and 26 operations to reach a plateau for operation time and fluoroscopy exposure, respectively (p < .001). Toepfer and Strässle found there was a significant decrease in operation time and fluoroscopy exposure after the first 19 procedures in their series (p < .001). With respect to complications, one study found a significant difference after the 42nd operation (p = .007). However, the remaining studies found that complication rates did not significantly change with increased technical proficiency. All seven studies were deemed to have a moderate risk of bias.

CONCLUSIONS

Surgeons can expect a learning curve of 20 to 40 operations before reaching technical proficiency with the MICA procedure. After the learning curve is achieved, surgeons can expect to see a significant decrease in both operation times and fluoroscopy exposure. No consistent significant difference was found in complications as one becomes more technically proficient with the procedure.

Surgical Precision of MICA and Reverdin-Isham Using 3D-Printed Guides: A Cadaveric Study

Background/Objectives: Hallux valgus is a common foot deformity that requires surgical correction to restore proper alignment. Precision in the osteotomies performed during these surgeries is critical to avoid complications and improve outcomes. However, variability in surgeon experience can negatively affect precision. In this context, advances in 3D printing have enabled the development of customized surgical guides, which may enhance precision and reduce variability among surgeons with different levels of expertise. This study aims to evaluate the effectiveness of a 3D-printed surgical guide in minimally invasive hallux valgus correction, focusing on the accuracy of osteotomies performed by novice surgeons, experienced surgeons, and theoretically trained consultants. Methods: An ex vivo study was performed with 30 cadaveric feet, divided into three groups according to the level of experience of the surgeons: 3D guide group, Master's students, professionals. All surgeons performed Akin and Reverdin-Isham osteotomies, but the experimental group (the 3D guide group) utilized a customized 3D-printed surgical guide for enhanced precision during these procedures. Radiographic measurements of osteotomy angles and alignment were taken after the interventions, and compared with the planned values. Statistical analyses were conducted to evaluate the variability in the precision of the cuts. Results: The use of the 3D-printed surgical guide significantly reduced angular variability in the experienced group, achieving higher levels of accuracy than experienced surgeons. Effect sizes, which ranged from small to large, indicated a greater impact on angle measurements (η2 = 0.46, p < 0.001); no significant differences were found between the groups in other evaluated parameters. Conclusions: The incorporation of 3D-printed surgical guides in hallux valgus surgery significantly improves osteotomy accuracy, particularly in less experienced surgeons. This suggests that these guides can help standardize procedures, reduce the learning curve, and lower intraoperative complications.

A comparison of three techniques for the osteosynthesis after minimal invasive osteotomies for hallux valgus

PURPOSE

Third and fourth-generation minimal invasive osteotomies (MIO) for the treatment of hallux valgus (HV) have become popular procedures worldwide with promising results due to the improvement in the fixation method. The tricortical cannulated screw placement remains a complex procedure that is technically challenging and requires a long skill learning curve with high radiation exposure mainly in the form of intensifier shots (IS) required for the MIO fixation. This study aims to compare the number of X-ray IS required using three different techniques for the cannulated guide placement.

METHODS

A retrospective cross-sectional observational and comparative study was conducted to assess the number of X-rays IS required for correct cannulated screw guide placement using three different techniques: traditional perforator, the drill and joystick, and K-wire first techniques.

RESULTS

A total of 53 MIS procedures from thirty-one patients in two different hospitals were included. IS X-rays were 155.1 ± 29.7 in the traditional technique (n = 14), 143.0 ± 43.2 in the drill and joystick technique (n = 22), and 85 ± 18.7 in the K-wires first technique (n = 17), p =  < 0.001 using one-way ANOVA.

CONCLUSIONS

The K-wire first technique statistically significantly decreases X-ray IS numbers p ≤ 0.001. There were no statistically significant differences between the traditional (after osteotomy K-wire placement) and the drill and joystick techniques (p = 0.36).

Minimally invasive hallux valgus surgery using 3D printed patient specific instrumentation

In this technical report study, we describe technique for performing the osteotomy and screw passage in minimally invasive fourth-generation hallux valgus surgery with transverse and akin extra-articular metaphyseal osteotomy (META) using a 3D-printed patient-specific surgical instrumentation guide. In an effort to minimize the learning curve and address the variability associated with technical corrections and screw placement, we have initiated the creation of personalized patient-specific instrumentation guides using 3D printing. Our hypothesis is that this approach will enhance safety, precision, decrease surgical time, and reduce exposure to radiation. Level of Evidence: Level V, expert opinion.

Intraoperative Angle Measurement of Anatomical Structures: A Systematic Review

Ensuring precise angle measurement during surgical correction of orientation-related deformities is crucial for optimal postoperative outcomes, yet there is a lack of an ideal commercial solution. Current measurement sensors and instrumentation have limitations that make their use context-specific, demanding a methodical evaluation of the field. A systematic review was carried out in March 2023. Studies reporting technologies and validation methods for intraoperative angular measurement of anatomical structures were analyzed. A total of 32 studies were included, 17 focused on image-based technologies (6 fluoroscopy, 4 camera-based tracking, and 7 CT-based), while 15 explored non-image-based technologies (6 manual instruments and 9 inertial sensor-based instruments). Image-based technologies offer better accuracy and 3D capabilities but pose challenges like additional equipment, increased radiation exposure, time, and cost. Non-image-based technologies are cost-effective but may be influenced by the surgeon's perception and require careful calibration. Nevertheless, the choice of the proper technology should take into consideration the influence of the expected error in the surgery, surgery type, and radiation dose limit. This comprehensive review serves as a valuable guide for surgeons seeking precise angle measurements intraoperatively. It not only explores the performance and application of existing technologies but also aids in the future development of innovative solutions.