Abstract
Background
Studies comparing the minimally invasive proximal chevron and Akin osteotomies (MIPCA) technique with conventional techniques, such as the open proximal chevron metatarsal osteotomy with the Akin procedure (open PCMO-Akin procedure), are limited. This study aimed to compare and evaluate operative MIPCA and open PCMO-Akin procedure outcomes in the surgical correction of moderate-to-severe hallux valgus deformities.
Methods
We conducted a retrospective comparison of clinical and radiographic outcomes between the MIPCA and open PCMO-Akin procedure in patients with a hallux valgus deformity, defined as a preoperative hallux valgus angle (HVA) of ≥ 30° and/or a first to second intermetatarsal angle of ≥ 13°. The postoperative complication rate was monitored in both groups for a minimum of 12 months. An unsatisfactory correction was defined as an HVA > 15° at final follow-up.
Results
We assigned 58 and 99 patients to the MIPCA or open PCMO-Akin procedure group, respectively. At final follow-up, no significant differences were observed between the groups in terms of clinical and radiographic parameters (p > 0.05), with the exception of the distal metatarsal articular angle (DMAA) (p = 0.012). No statistically significant postoperative changes in the DMAA were observed in the MIPCA group (p = 0.875). Five patients (5.1%) experienced postoperative hallux varus in the open PCMO-Akin procedure group, whereas no such cases were observed in the MIPCA group. No statistically significant difference in the rate of unsatisfactory correction was observed between the groups at the final follow-up (MIPCA group, 15.5%; open PCMO-Akin procedure group, 10.1%; p = 0.315).
Conclusions
The MIPCA technique is a viable alternative to the open PCMO-Akin procedure for correcting moderate-to-severe hallux valgus deformities. Given the potential lack of postoperative changes in the DMAA following the MIPCA technique, careful consideration is advised when applying this technique to patients with a large DMAA.
Keywords: Hallux valgus, Operative outcome, Proximal chevron metatarsal osteotomy, Percutaneous, Minimally invasive proximal chevron and Akin osteotomies
Hallux valgus is defined as a deformity of the first ray of the foot, characterized as lateral deviation of the great toe and medial deviation of the first metatarsal, resulting in an increased hallux valgus angle (HVA; the angle formed between the long axes of the first metatarsal and the proximal phalanx of the hallux) and an increased first to second intermetatarsal angle (IMA; the angle formed between the long axes of the first and second metatarsals). A deformity with an HVA ≥ 30° or an IMA ≥ 13° is generally considered to be moderate to severe.
The minimally invasive chevron and Akin osteotomies (MICA) technique has recently become a popular technique for the surgical correction of hallux valgus. This technique employs a chevron-shaped osteotomy of the metatarsal bone, performed with a Shannon burr at the distal part of the metatarsal. Studies have reported that the MICA is a safe and effective surgical technique, providing a less noticeable postoperative scar while achieving correction outcomes comparable with those of open procedures.1,2,3,4,5) However, similar to when open distal chevron metatarsal osteotomy (DCMO) and proximal chevron metatarsal osteotomy (PCMO) techniques were widely used, the suitability of a distal metatarsal osteotomy procedure for correcting more severe hallux valgus deformities remains to be elucidated. Ongoing discussion has led to efforts to compare the efficacy of minimally invasive proximal chevron and Akin osteotomies (MIPCA) with the MICA technique, providing further insight into current practices in this area.6,7) Findings from these comparative studies suggest that the MIPCA technique may offer certain advantages over the MICA technique in managing moderate-to-severe hallux valgus, despite potentially reduced stability at the osteotomy site using the MIPCA technique. Several comparative studies between the MICA technique and other open techniques have been undertaken;8,9) however, studies comparing MIPCA with more conventional approaches, such as the open PCMO technique, are limited.
This study aimed to compare the clinical and radiographic outcomes of the MIPCA technique and those of open PCMO with the Akin procedure (open PCMO-Akin procedure) in the treatment of moderate-to-severe hallux valgus deformities. Our objective was to evaluate whether the MIPCA technique could serve as a viable alternative to the open PCMO-Akin procedure. We hypothesized that MIPCA and open PCMO-Akin procedures would yield comparable postoperative clinical and radiographic results, particularly concerning deformity correction and the rate of postoperative complications.
METHODS
The study was approved by the Institutional Ethics Review Committee of Inje University Ilsan Paik Hospital (IRB No. 2020-09-030) and conducted in accordance with the tenets of the Declaration of Helsinki. Written informed consent was obtained from all participating patients.
Study Design and Patients
This retrospective study analyzed MIPCA and open PCMO-Akin procedure outcomes in patients who had undergone surgery for hallux valgus deformities between January 2010 and December 2022. A list of consecutive patients who underwent surgery for this condition was initially created, identifying those treated specifically with an MIPCA or an open PCMO-Akin procedure through a review of surgical records. Inclusion criteria comprised skeletally mature adults (aged ≥ 18 years) with a preoperative HVA of ≥ 30° and/or an IMA of ≥ 13°. Additionally, patients needed to have been followed up postoperatively for at least 12 months. Exclusion criteria comprised patients with systemic inflammatory conditions (e.g., rheumatoid arthritis, gout), a history of trauma affecting foot alignment, or a history of prior hallux valgus surgery on the affected side.
Patients who met our criteria were categorized into 2 groups based on the surgical method, namely, those who had undergone an MIPCA and those who had undergone the open PCMO-Akin procedure. Open PCMO-Akin procedures were performed between 2010 and 2017, whereas MIPCAs were performed between 2017 and 2022.
Sample Size Calculation
The study’s sample size was calculated using the formula for comparing 2 groups with a quantitative outcome measure. Study power was set at 80% and the level of significance level was set to p < 0.05. The primary endpoint for determining the sample size was the pre- to postoperative measurement change in the HVA. This calculation was informed by a prior study that examined the postoperative HVA following the MIPCA technique.6) An effect size of 5° and a standard deviation of 7.5 were used in the calculation. Based on these parameters, the required sample size was 34 patients per group. To allow for a possible 10% dropout rate during follow-up, we targeted a minimum of 38 patients per group.
Operative Technique and Postoperative Care
All surgeries were performed by 2 experienced orthopedic surgeons (JYC and JSS). Patients received either general or spinal anesthesia or an ultrasound-guided sciatic and femoral nerve block. A pneumatic tourniquet was applied to the distal thigh, with each patient placed in a supine position.
For the MIPCA technique, established protocols from previous studies were followed,6,7) using Shannon burrs with a diameter of 2 mm × 20 mm for the metatarsal and 2 mm × 12 mm for the Akin osteotomies, respectively. The primary deformity correction focused on valgus angulation of the distal fragment, facilitated by inserting curved mosquito forceps into its medullary space. Fixation involved a 3.0-mm cannulated screw and/or one or two 1.4-mm Kirschner wires (K-wires) within the intramedullary canal of the distal fragment via the metatarsal osteotomy site. For further stabilization, additional intermetatarsal fixation was performed between the first and second metatarsals using a 1.8-mm K-wire or a 3.0-mm cannulated screw (Fig. 1A).
Fig. 1. Additional intermetatarsal fixation. (A) Additional intermetatarsal fixation was necessary in most of the patients in the minimally invasive proximal chevron and Akin osteotomies group. (B) In patients who underwent open proximal Chevron metatarsal osteotomy, additional intermetatarsal fixation was necessary when there was a large degree of correction, resulting in a small osteotomy contact surface, or when interfragmentary fixation was unstable.
In the open PCMO-Akin procedure, deformity correction involved lateral translation and valgus angulation of the distal fragment, with intramedullary fixation using two or three 1.4- or 1.6-mm K-wires. When substantial correction reduced the osteotomy contact surface, additional intermetatarsal fixation between the distal fragments of the first and second metatarsals was implemented, similar to the MIPCA technique (Fig. 1B).
For all patients undergoing MIPCA, a percutaneous adductor tenotomy10) was performed after correction, while those who had undergone the open PCMO-Akin procedure had a trans-articular adductor tenotomy. In cases requiring a second Weil osteotomy, adductor tenotomy was conducted via an incision on the dorsum of the second metatarsophalangeal joint in both groups.
Postoperatively, both groups adhered to heel gait restrictions using bespoke forefoot offloading orthotic footwear with specifically designed rigid soles for 6 weeks. Thereafter, any additional intermetatarsal fixation was removed under local anesthesia, and gradual forefoot weight-bearing was introduced. Bone union was generally observed within 8 to 12 weeks, after which the removal of any remaining devices was considered.
Assessments
Demographic data, including patient age at surgery, sex, affected side, and body mass index (BMI), were collected. Additional information regarding the surgical procedure, such as operative time, type of anesthesia, and any concurrent procedures, was documented. Radiographic assessments were conducted on standing anteroposterior radiographs of the foot, both preoperatively and at the final follow-up, measuring parameters such as the HVA, IMA, distal metatarsal articular angle (DMAA), relative second metatarsal length, and medial sesamoid position (assessed using the Hardy and Clapham method11)). The relative second metatarsal length was defined as the perpendicular distance from the apex of the second metatarsal head to a line drawn between the apices of the first and third metatarsals. To isolate the effect of the first metatarsal osteotomy, cases involving additional procedures on the second or third metatarsals, such as a Weil osteotomy, a minimally invasive distal metatarsal metaphyseal osteotomy, or a tarsometatarsal arthrodesis, were excluded. The talo-first metatarsal angle (Meary angle) was also measured on standing lateral foot radiographs, with a negative value indicating pes planus. All radiographic measurements were performed by 2 orthopedic surgeons (JYC and SOJ). For reliability assessment, 30 randomly selected cases were reviewed twice with a 2-month interval between readings, evaluating both interobserver reliability and intraobserver reproducibility through intraclass correlation coefficients, with detailed results provided in the Supplementary Table 1.
Functional outcomes were assessed preoperatively and at the final follow-up using Foot and Ankle Ability Measure (FAAM) subscale scores for activities of daily living (ADL) and sports.12,13,14) The ADL and sports subscale scores ranged from 0 to 84 and from 0 to 32, respectively, based on patient-completed self-assessment questionnaires. Postoperative complications observed during follow-up were recorded, and the incidence of each complication was analyzed and compared between the 2 procedures. Unsatisfactory correction was defined as an HVA > 15° at the final follow-up.7)
Statistical Analyses
Means and standard deviations for all dependent parameters were calculated, and data normality was evaluated using a Kolmogorov-Smirnov test. For between-group comparisons of demographic characteristics, operative time, and clinical and radiographic parameters, an independent t-test was applied. A paired t-test was used to compare preoperative and postoperative clinical and radiographic parameters within each group. A chi-square test was used to assess differences in the proportion of women in each group and the rate of unsatisfactory corrections. Statistical analyses were performed using SPSS version 21 (IBM Corp.) software, with a significance level of p < 0.05.
RESULTS
Demographic and Operation-Related Data in the 2 Groups
A patient-selection algorithm is illustrated in Fig. 2. Initially, 301 patients who underwent correctional surgery for hallux valgus were included. Following application of the algorithm, 126 patients (157 cases) were included in the study, among whom 58 and 99 patients were assigned to the MIPCA and open PCMO-Akin procedure groups, respectively.
Fig. 2. The patient selection algorithm. Of 301 initial patients, 126 (157 cases) were included in the study. Of these, 58 and 99 patients were assigned to the minimally invasive proximal chevron and Akin osteotomies (MIPCA) and open proximal Chevron metatarsal osteotomy (PCMO) procedure groups, respectively. HVA: hallux valgus angle, IMA: first to second intermetatarsal angle.
Table 1 presents the demographic and operation-related data for the MIPCA and open PCMO-Akin procedure groups. No significant differences were observed between the 2 groups in terms of mean age at the time of surgery, sex, or BMI (p > 0.05). However, the operative time was significantly shorter in the open PCMO-Akin procedure group (p = 0.018). Regarding concomitant surgical procedures performed simultaneously on the ipsilateral foot, a second metatarsal shortening procedure (a Weil osteotomy or a minimally invasive distal metatarsal metaphyseal osteotomy)15,16) was most frequently performed in both groups, followed by a medial displacement calcaneal osteotomy.
Table 1. Demographic and Operation-Related Data of the 2 Groups According to the Correction Method.
| Variable | MIPCA (58 cases in 46 patients) | Open PCMO-Akin procedure (99 cases in 80 patients) | p-value |
|---|---|---|---|
| Age at the time of surgery (yr) | 58.8 ± 7.0 | 55.5 ± 11.6 | 0.571 |
| Sex, female | 42 (91.3) | 75 (93.8) | 0.608 |
| Side (right : left) | 35 : 23 | 49 : 50 | - |
| Body mass index (kg/m2) | 25.9 ± 3.4 | 26.3 ± 3.7 | 0.762 |
| Follow-up duration (mo) | 21.7 ± 6.8 | 31.4 ± 12.3 | 0.001 |
| Operative time (min) | 42.0 ± 8.8 | 28.6 ± 5.9 | 0.018 |
| Type of anesthesia | General anesthesia, 23; sciatic and femoral nerve block under ultrasound guidance, 35 | General anesthesia, 25; spinal anesthesia, 52; sciatic and femoral nerve block under ultrasound guidance, 22 | - |
| Concomitant surgical procedures performed on the ipsilateral foot | 2nd Weil osteotomy, 19; DMMO on the 2nd metatarsal, 6; MDCO, 12; 2nd TMT arthrodesis, 4; 2nd, 3rd TMT arthrodesis, 1; 2nd hammer toe correction, 4; bunionette correction, 6 | 2nd Weil osteotomy, 30; MDCO, 20; 2nd TMT arthrodesis, 6; 2nd, 3rd TMT arthrodesis, 3; Cotton osteotomy, 2; bunionette correction, 7 | - |
Values are presented as mean ± standard deviation or number of cases (%).
MIPCA: minimally invasive proximal chevron and Akin osteotomies, PCMO: proximal chevron metatarsal osteotomy, DMMO: minimally invasive distal metatarsal metaphyseal osteotomy, MDCO: medial displacement calcaneal osteotomy, TMT: tarsometatarsal.
Outcome Comparison between the 2 Groups
Table 2 presents the pre- and postoperative clinical and radiographic parameters at the final follow-up. No significant differences were observed between the 2 groups in any of the clinical or radiographic parameters (p > 0.05), except for the DMAA at the final follow-up, which was significantly lower in the open PCMO-Akin procedure group (p = 0.012). In both groups, significant postoperative changes were noted in terms of the HVA, IMA, medial sesamoid position, Meary angle, and the FAAM-ADL and FAAM-sports scores (p < 0.05). No significant difference was observed in the MIPCA group in terms of postoperative changes in the DMAA (p = 0.875), but the open PCMO-Akin procedure group showed a significant decrease in the DMAA postoperatively (p = 0.014). There was no significant postoperative change in the relative second metatarsal length in either group (MIPCA group, p = 0.133; open PCMO-Akin procedure group, p = 0.136).
Table 2. All Clinical and Radiographic Parameters of the 2 Groups.
| Variable | MIPCA (58 cases in 46 patients) | Open PCMO-Akin procedure (99 cases in 80 patients) | p-value | |
|---|---|---|---|---|
| HVA (°) | Preoperative | 36.6 ± 5.8 | 34.4 ± 5.7 | 0.513 |
| Final follow-up | 13.4 ± 7.3 | 13.3 ± 6.5 | 0.993 | |
| p-value | < 0.001 | < 0.001 | ||
| IMA (°) | Preoperative | 15.3 ± 3.6 | 16.6 ± 3.8 | 0.772 |
| Final follow-up | 7.2 ± 3.1 | 7.5 ± 3.4 | 0.816 | |
| p-value | 0.01 | 0.01 | ||
| DMAA (°) | Preoperative | 26.2 ± 17.3 | 24.5 ± 17.4 | 0.861 |
| Final follow-up | 27.4 ± 15.7 | 12.3 ± 7.2 | 0.012 | |
| p-value | 0.875 | 0.014 | ||
| Relative second MT length (mm)* | Preoperative | 3.4 ± 1.3 | 3.6 ± 1.4 | 0.974 |
| Final follow-up | 3.9 ± 1.8 | 4.1 ± 2.5 | 0.972 | |
| p-value | 0.133 | 0.136 | ||
| Medial sesamoid position | Preoperative | 6 (5–7) | 6 (5–7) | 0.945 |
| Final follow-up | 4 (3–5) | 4 (3–5) | 0.879 | |
| p-value | 0.001 | 0.001 | ||
| Meary angle (°) | Preoperative | –10.2 ± 7.9 | –9.5 ± 7.6 | 0.652 |
| Final follow-up | –3.0 ± 10.5 | –4.2 ± 9.5 | 0.471 | |
| p-value | 0.01 | 0.01 | ||
| FAAM-ADL score | Preoperative | 59.7 ± 15.2 | 58.3 ± 15.7 | 0.872 |
| Final follow-up | 72.6 ± 13.7 | 74.9 ± 13.9 | 0.677 | |
| p-value | < 0.001 | < 0.001 | ||
| FAAM-Sports score | Preoperative | 17.3 ± 7.2 | 17.7 ± 7.3 | 0.901 |
| Final follow-up | 23.8 ± 6.3 | 24.3 ± 6.4 | 0.881 | |
| p-value | < 0.001 | < 0.001 | ||
Values are presented as mean ± standard deviation or median (interquartile range).
MIPCA: minimally invasive proximal chevron and Akin osteotomies, PCMO: proximal chevron metatarsal osteotomy, HVA: hallux valgus angle, IMA: first to second intermetatarsal angle, DMAA: distal metatarsal articular angle, MT: metatarsal, FAAM: Foot and Ankle Ability Measure, ADL: activities of daily living.
*The cases with surgical procedures on the second or third metatarsal (Weil osteotomy, minimally invasive distal metatarsal metaphyseal osteotomy, or tarsometatarsal arthrodesis) were excluded to evaluate the genuine effect of the first metatarsal osteotomy.
Postoperative Complications
Table 3 summarizes the postoperative complications in the 2 groups. No significant differences were observed in the rates of postoperative superficial/deep wound infections or digital nerve injuries between the groups. However, postoperative hallux varus was observed in 5 of 99 patents (5.1%) after the open PCMO-Akin procedure (Fig. 3), but no cases of hallux varus were observed following the MIPCA technique. The rate of unsatisfactory corrections at the final follow-up was higher in the MIPCA group than in the open PCMO-Akin procedure group (15.5% vs. 10.1%, respectively; p = 0.315).
Table 3. Postoperative Complications in the 2 Groups.
| Variable | MIPCA (58 cases in 46 patients) | Open PCMO-Akin procedure (99 cases in 80 patients) | p-value |
|---|---|---|---|
| Superficial wound infection | 4 (6.9) | 7 (7.1) | 0.967 |
| Deep wound infection | 0 | 0 | - |
| Digital nerve injury | 3 (5.2) | 6 (6.1) | 0.817 |
| Osteotomy site nonunion | 0 | 0 | - |
| Hallux varus | 0 | 5 (5.1) | - |
| Unsatisfactory correction* | 9 (15.5) | 10 (10.1) | 0.315 |
| Other | 0 | FHL rupture, 1 (1.0) |
Values are presented as number (%).
MIPCA: minimally invasive proximal chevron and Akin osteotomies, PCMO: proximal chevron metatarsal osteotomy, FHL: flexor hallucis longus.
*Unsatisfactory correction was defined as a hallux valgus angle greater than 15° at the final follow-up.
Fig. 3. Postoperative hallux varus deformity. Postoperative hallux varus was observed in 5 of 99 patients (5.1%) after the open proximal Chevron metatarsal osteotomy-Akin procedure; however, this deformity was not observed postoperatively in patients who underwent the minimally invasive proximal chevron and Akin osteotomies technique.
DISCUSSION
Our findings indicate that the postoperative clinical and radiographic outcomes between the MIPCA and open PCMO-Akin procedure did not differ significantly in terms of managing moderate-to-severe hallux valgus deformity. While the open PCMO-Akin procedure allowed for direct correction of the DMAA, this adjustment may not be achievable with the MIPCA technique. Moreover, we observed a risk of overcorrection leading to hallux varus with the open PCMO-Akin procedure, whereas such complications were not observed with the MIPCA technique. No statistically significant difference in the rate of unsatisfactory correction between the 2 techniques was observed at the final follow-up.
Since the development of the third-generation minimally invasive hallux valgus correction technique, which utilizes chevron-type osteotomy at the distal metatarsal level, several studies have demonstrated satisfactory outcomes even in moderate-to-severe deformities, with clear evidence regarding its correctional effectiveness.17,18,19,20) However, in our clinical experience, there have been instances where an MICA technique alone was inadequate for full correction, highlighting the importance of considering factors such as osteotomy shape, soft-tissue dissection, and osteotomy location. While we agree that the MICA technique is generally effective in addressing most moderate-to-severe hallux valgus cases, we remain cautious about its capacity to fully correct all severe cases. This underlines the need for alternative approaches within the MICA technique. In this context, we propose that the MIPCA technique could serve as a practical alternative. Additionally, from a cosmetic standpoint, converting an open PCMO-Akin procedure to an MIPCA may offer a greater reduction in scarring compared to converting an open DCMO-Akin procedure to the MICA.
Few studies have explored third-generation minimally invasive techniques at the proximal metatarsal level.6,7) These studies suggest that proximal metatarsal osteotomy may offer advantages over distal-level osteotomy for correcting deformities. In a comparative study by Choi et al.7) concerning patients with severe hallux valgus deformity treated using MIPCA and MICA techniques, a higher rate of unsatisfactory corrections was observed with the MICA technique compared with the MIPCA technique after > 2 years of follow-up, primarily because of insufficient initial correction. In contrast, while the MIPCA technique showed adequate initial correction, a tendency for correction loss was observed over time, likely owing to less stable fixation at the osteotomy site. Our clinical experience aligns with these findings. Therefore, we recommend considering additional intermetatarsal fixation when osteotomy site fixation alone proves insufficient, especially for proximal osteotomies with a longer lever arm.
We initially anticipated that the MIPCA technique would produce results comparable with those of the open PCMO-Akin procedure. However, significant differences were observed between the 2 methods. In open techniques, extensive soft-tissue dissection around the osteotomy site facilitates both lateral translation and valgus angulation of the distal fragment, allowing for a wider range of deformity corrections. While this level of dissection can occasionally lead to overcorrection, resulting in postoperative hallux varus, it provides the advantage of enabling easy supination of the distal fragment. Additionally, the degree of supination can be visually controlled, which supports 3-dimensional correction and may positively affect postoperative reduction of the DMAA. In contrast, the MIPCA technique relies primarily on valgus angulation of the distal fragment owing to limited soft-tissue dissection, potentially leading to no change—or even an increase—in the DMAA compared with open techniques. It has been well established that pronation of the first metatarsal correlates with an increase in the DMAA.21,22) Addressing an increase in the DMAA remains challenging, even in open techniques. Our experience includes cases where the open PCMO-Akin procedure resulted in similar DMAA increases, yet postoperative correction satisfaction varied (Fig. 4). We suspect that factors such as soft-tissue balance and first metatarsal length likely contribute to determining surgical outcomes.
Fig. 4. Different correction results even when an increased distal metatarsal articular angle (DMAA) was observed. Instances with similarly increased DMAAs were observed at the final follow-up. The correction was determined to be either satisfactory (A) or unsatisfactory (B).
Another difference between the open PCMO-Akin procedure and the MIPCA technique is the gap at the osteotomy site. In an open PCMO, the use of an oscillating saw creates a relatively narrow osteotomy gap. Through adjusting the angle between the upper and lower osteotomy lines at the apex to approximately 30°, the distal metatarsal fragment can securely fit into the proximal site, providing enhanced stability. As a result, stable fixation is generally achievable with multiple intramedullary K-wires alone. Conversely, a Shannon burr is used in the MIPCA technique, creating a significantly wider osteotomy gap, and narrowing the apex angle is almost impossible, which results in a less stable osteotomy site. Additionally, because of the limited capacity for bicortical fixation with screws or K-wires, alternative fixation methods or materials are essential to maintain stability. Currently, we address this by employing intermetatarsal fixation; however, there is a risk of fixation material breakage if the patient initiates forefoot weight-bearing prematurely. In summary, while the MIPCA technique offers a powerful correction option and is comparable to the open PCMO-Akin procedure, the main challenge remains in achieving stable fixation.
This study has some limitations. The MIPCA group had a relatively short mean follow-up duration of < 2 years, which may limit the assessment of long-term outcomes. The study’s retrospective design and the relatively small sample size for each group could affect the generalizability of our results. Moreover, we were not able to assess first metatarsal pronation and supination in the axial plane, and the use of weight-bearing computed tomography for both pre- and postoperative evaluations could offer a deeper understanding of the MIPCA technique’s effectiveness.23,24,25) Furthermore, comparisons between MIPCA techniques and other open osteotomy procedures may provide valuable insights. Despite these limitations, our study highlights the MIPCA technique’s potential as a viable alternative to the open PCMO-Akin procedure in treating moderate-to-severe hallux valgus deformity.
In conclusion, the MIPCA technique is a viable alternative to an open PCMO-Akin procedure for correcting moderate-to-severe hallux valgus deformities. However, while the open PCMO-Akin procedure allows for comprehensive deformity correction via extensive soft-tissue dissection, the MIPCA technique, which minimizes the effect on soft tissue, has limitations in simultaneously achieving lateral translation and valgus angulation of the distal fragment. Consequently, postoperative DMAA may remain unchanged post-MIPCA surgery, necessitating caution when applying this technique to patients with a high DMAA. Our findings indicate that the rate of unsatisfactory correction at the final follow-up does not differ significantly between the techniques.
Footnotes
CONFLICT OF INTEREST: No potential conflict of interest relevant to this article was reported.
SUPPLEMENTARY MATERIAL
Supplementary material is available in the electronic version of this paper at the CiOS website, www.ecios.org.
The Statistics for Inter-observer Reliability and Intra-observer Reproducibility for 30 Randomly Selected Cases
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Supplementary Materials
The Statistics for Inter-observer Reliability and Intra-observer Reproducibility for 30 Randomly Selected Cases