Hypermobility in Hallux Valgus

Immediate effect of hallux valgus surgery on the biomechanical behavior of the first ray

BACKGROUND

The surgical treatment of hallux valgus (HV) deformity has been the subject of countless publications but few focus on the altered windlass mechanism or analyze the biomechanical behavior immediately after surgery.

METHODS

Patients treated for HV between January and March 2023 were included. The surgery consisted of a L-reverse first metatarsal osteotomy. To analyze the windlass mechanism we record two different measurements; the isolated first metatarsophalangeal joint (MTPJ) dorsiflexion angle (IDA) and dynamic plantarization of the first metatarsal head when performing first MTPJ dorsiflexion imprinting a mark on a modeling foam.

RESULTS

A total of 30 patients diagnosed with symptomatic HV were included. In all patients, a change in the IDA angle was evident, being overall statistically significant. About modeling foam imprinted mark, all measurements, in all planes of space, had a clear tendency to increase, which turned out to be statistically significant (p < 0.001).

CONCLUSIONS

An altered windlass mechanism may be successfully recovered immediately after hallux valgus deformity surgery. This could be evinced by an indirect measurement analyzing the imprint of the head of the first metatarsal in a modeling foam and the IDA.

LEVELS OF EVIDENCE II

None.

Characteristics of hindfoot morphology and ankle range of motion in young women with hallux valgus

BACKGROUND

Hallux valgus occurs more frequently in women as they age; therefore, it is beneficial to prevent hallux valgus in younger women. The purpose of this study was to clarify the characteristics of hindfoot morphology and the range of motion of the ankle joint with hallux valgus in young women.

METHODS

The participants were 140 young women (mean age 18.8 ± 0.6 years). A three-dimensional footprint automatic measurement apparatus was used to measure the hallux valgus angle in the standing position and the arch-height ratio and heel-floor angle (HFA) in the standing and chair-sitting positions. The amount of change in foot morphology owing to differences in posture was calculated. The range of motion of the ankle joint dorsiflexion, plantarflexion, inversion, and eversion was measured. Participants were classified into two groups according to the presence of hallux valgus. Statistical analysis was used to compare hindfoot morphology and range of motion between the two groups, and the correlation between foot morphology and range of motion was investigated depending on the presence of hallux valgus.

RESULTS

With hallux valgus, the HFA tilted inwards (p = 0.010), and the change in the arch-height ratio due to the difference in posture was large (p = 0.021). There was no difference in the range of motion of the ankle joints with or without hallux valgus. In women with hallux valgus, the amount of change in arch height and HFA was correlated with the range of motion of eversion (r = 0.391, p = 0.027; r = -0.362, p = 0.042).

CONCLUSIONS

With hallux valgus, the hindfoot pronated, and the arch height decreased from sitting to standing. Furthermore, the amount of change in the hindfoot and midfoot due to posture was related to the range of motion of eversion.

Intra‑ and Interobserver Reliability of Yamaguchi's Method for the Assessment of First Metatarsal Pronation in Hallux Valgus Deformity

Pronation of the first metatarsal is a risk factor for the formation and progression of the hallux valgus deformity. Recently, Yamaguchi et al published a study that showed how the round sign increases on digitally reconstructed radiography taken from a CT scan when pronation is applied. In this study, the shape of the lateral edge of the first metatarsal head was evaluated on weightbearing dorsoplantar radiographs. Yamaguchi's signs were presented to observers after the visual presentation of each foot as an image. The best-fit circle was drawn using the PACS drawing function. Ninety radiographs of adults presenting hallux valgus deformities were classified as mild-to-moderate, based on hallux valgus angle and intermetatarsal angle. The global average observations were 3.72 ± 3.92 (range 2.3°-4.6°). The interclass correlation (Fleiss Kappa index κ = 0.225) and the Spearman correlation (0.16 of Kappa) coefficients were poor for interobserver measurements and statistically significant. Using the linear model, there was no significant variability between the repetitions corresponding to each observer (t-value -1.527, p value .127). Our findings show that the Yamaguchi method can be very subjective and should not be the exclusive technique to assess the rotation of the first metatarsal or head roundness.

Intra- and Interobserver Reliability of the New Classification System of Progressive Collapsing Foot Deformity

BACKGROUND

Historical concept of flatfoot as posterior tibial tendon dysfunction (PTTD) has been questioned. Recently, the consensus group published a new classification system and recommended renaming PTTD to Progressive Collapsing Foot Deformity (PCFD). The new PCFD classification could be effective in providing comprehensive information on the deformity. To date, there has been no study reporting intra- and interobserver reliability and the frequency of each class in PCFD classification.

METHODS

This was a single-center, retrospective study conducted from prospectively collected registry data. A consecutive cohort of PCFD patients evaluated from February 2015 to October 2020 was included, consisting of 92 feet in 84 patients. Classification of each patient was made using characteristic clinical and radiographic findings by 3 independent observers. Frequencies of each class and subclass were assessed. Intraobserver and inteobserver reliabilities were analyzed with Cohen kappa and Fleiss kappa, respectively.

RESULTS

Mean sample age was 54.4, 38% was male and 62% were female. 1ABC (25.4%) was the most common subclass, followed by 1AC (8.7%) and 1ABCD (6.9%). Only a small percentage of patients had isolated deformity. Class A was the most frequent component (89.5%), followed by C in 86.2% of the cases. Moderate interobserver reliability (Fleiss kappa = 0.561, P < .001, 95% CI 0.528-0.594) was found for overall classification. Very good intraobserver reliability was found (Cohen kappa = 0.851, P < .001, 95% CI 0.777-0.926).

CONCLUSION

Almost half (49.3%) of patients had a presentation dominantly involving the hindfoot (A) with various combinations of midfoot and/or forefoot deformity (B), (C) with or without subtalar joint involvement (D). The new system may cover all possible combinations of the PCFD, providing a comprehensive description and guiding treatment in a systematic and individualized manner, but this initial study suggests an opportunity to improve overall interobserver reliability.

LEVEL OF EVIDENCE

Level III, retrospective diagnostic study.

Early results and complication rate of the LapiCotton procedure in the treatment of medial longitudinal arch collapse: a prospective cohort study

INTRODUCTION

Instability/collapse of the medial column has been associated with many conditions, particularly progressive collapsing foot deformity (PCFD), hallux valgus (HV), and midfoot arthritis (MA). Restoration of first ray length and sagittal plane alignment to restore the foot tripod is essential when treating these deformities. This study aimed to assess early results, healing, and complication rate of a distraction dorsal opening plantarflexion wedge allograft first tarsometatarsal joint fusion (LapiCotton Procedure) in patients with collapse/instability of the medial column.

METHODS

In this prospective cohort study, we included PCFD, HV, and MA patients that underwent a LapiCotton procedure. Fusion site healing was defined by > 50% bone bridging in both interfaces between allograft wedge and host bone using weight-bearing computed tomography (WBCT) after 3 months. First ray collapse radiographic correction and minor and major complications (deep dehiscence, deep infection, and reoperation) were assessed.

RESULTS

A total of 22 patients (22 feet) were included (11 PCFD, 6 MA, and 5 of HV patients). Mean follow-up was 5.9 months (range 3-12) and median allograft size was 8 mm (range 5-19 mm). Bone healing was observed in 91% of cases. Two minor complications (9%, both superficial dehiscence) and one major complication (4.5%, deep infection) were observed. Statistically significant improvement of the sagittal plane talus-first metatarsal angle was observed, with mean improvement of 9.4° (95% CI 6.7-12.1°; p < 0.0001).

CONCLUSION

In this prospective cohort study of 22 patients treated with the LapiCotton procedure for medial longitudinal arch collapse/instability, we observed a low complication rate (9% minor, 4.5% major), high healing rate after 3 months (91%), one clinically stable radiographic non-union (4.5%) and one unstable non-union (4.5%) needing reoperation. Our results demonstrate promising initial results for LapiCotton technique in treating collapse of the medial longitudinal arch in patients with PCFD, MA and HV deformities. Long-term results are needed to confirm these promising results.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

Descriptive Quantitative Analysis of First Metatarsal Sagittal Plane Motion

Evaluation of the sagittal plane motion of the first ray is a commonly accepted physical examination technique performed during the assessment and treatment of the hallux valgus deformity. Excessive or abnormal motion in this location, termed "hypermobility," has also traditionally been strongly associated with surgical decision-making and serves as a widely accepted indication for performance of the first metatarsal-medial cuneiform arthrodesis procedure. The objective of this investigation was to perform an analysis of first ray sagittal plane motion from a large population in order to determine the descriptive quantitative characteristics of the data set. First metatarsal sagittal plane motion was measured from a group of 149 subjects (298 feet) with a Klaue device. The mean total first metatarsal sagittal plane motion was 9.37 ± 2.39 mm (3.97-18.76). The data set was found to demonstrate many of the characteristics of a normally distributed population based on the histogram distribution, skewness (0.651), and kurtosis (0.761). No difference was observed between measurement of total sagittal plane motion between right and left feet (9.13 ± 2.37 mm vs 9.61 ± 2.40 mm; p = .081), nor between male and female subjects (9.29 ± 2.27 mm vs 9.58 ± 2.70 mm; p = .352). No substantial correlation was observed between total sagittal plane motion and subject age (Pearson correlation -0.053; p = .522). Results indicate that first ray sagittal plane motion might be best considered as a continuous variable as opposed to categorical variable, and might help objectify the difference between "normal" and "abnormal" motion.

Technical Tip Kerfing for Lapidus Arthrodesis: Deformity Correction With Minimal Bone Resection

The Lapidus arthrodesis can be a powerful but technically challenging procedure. Common pitfalls include gapping at the arthrodesis site, shortening, and residual malalignment. Herein is described a simple and reproducible technique to obtain a congruent arthrodesis site with excellent deformity correction and minimal bone loss by the use of joint kerfing.

Finite Element Analysis of Generalized Ligament Laxity on the Deterioration of Hallux Valgus Deformity (Bunion)

Hallux valgus is a common foot problem affecting nearly one in every four adults. Generalized ligament laxity was proposed as the intrinsic cause or risk factor toward the development of the deformity which was difficult to be investigated by cohort clinical trials. Herein, we aimed to evaluate the isolated influence of generalized ligament laxity on the deterioration using computer simulation (finite element analysis). We reconstructed a computational foot model from a mild hallux valgus participant and conducted a gait analysis to drive the simulation of walking. Through parametric analysis, the stiffness of the ligaments was impoverished at different degrees to resemble different levels of generalized ligament laxity. Our simulation study reported that generalized ligament laxity deteriorated hallux valgus by impairing the load-bearing capacity of the first metatarsal, inducing higher deforming force, moment and malalignment at the first metatarsophalangeal joint. Besides, the deforming moment formed a deteriorating vicious cycle between hallux valgus and forefoot abduction and may result in secondary foot problems, such as flatfoot. However, the metatarsocuneiform joint did not show a worsening trend possibly due to the overriding forefoot abduction. Controlling the deforming load shall be prioritized over the correction of angles to mitigate deterioration or recurrence after surgery.

Hypermobility of the First Ray: the Cinderella of the measurements conventionally assessed for correction of Hallux Valgus

Background and aim of the work:

hypermobility of the first ray (FRH) began to be considered as a pathological entity from Morton’s studies and was associated as a primary cause of hallux valgus (HV). Currently, this relationship is in discussion, and various authors consider FRH as a consequence of the deformity. The purpose of this narrative review is to summarise the most influential publications relating to First Ray Mobility (FRM) to increase knowledge and promote its conventional assessment during clinical practice.

Methods:

papers of the last century were selected to obtain a homogeneous and up-to-date overview of I-MTCJ mobility and HV, as well as their relationship and management.

Results:

in recent years, FRH was studied from a biomechanical and pathophysiologic point of view. There is still not enough data regarding the aetiology of FRM. The higher rate of instability found in HV lacks an explanation of which is the cause and which is the effect. However, the Lapidus arthrodesis is still a valid method in cases of FRH and HV, even if is not rigorously indicated to treat both. When approaching FRH, radiographic or clinical findings are mandatory for the right diagnosis.

Conclusions:

FRM is an important factor that must be considered in routine clinical practice and prior and post HV surgery, as much as the conventional parameters assessed. Surgeons should consider performing I-MTCJ arthrodesis only if strictly necessary, also paying attention to soft tissue balancing. Improving the measurement of FRH could be useful to determine if it is a cause or effect of the HV deformity. (www.actabiomedica.it)