Adjusted Indirect and Mixed Comparisons of Conservative Treatments for Hallux Valgus: A Systematic Review and Network Meta-Analysis

Immediate effect of the use of toe separators on dynamic balance and ankle range of motion: a pilot study

BACKGROUND AND OBJECTIVES

Injuries involving ankle stability and range of motion are among the most frequent in athletes and in the general population. In response, this study aimed to assess the immediate effects of toe separators on dynamic stability and ankle range of motion in healthy young individuals.

METHODS

Among the 68 eligible participants, 50 healthy and active subjects completed all trials. The impact of the intervention was evaluated using the Weight Bearing Lunge Test and Y-Test. The control condition performed the tests without toe separators, while the experimental condition performed the tests with toe separators. All participants performed both conditions with a wash-out period of at least 7 days between trials.

RESULTS

Statistical analysis revealed no significant differences in dynamic balance (p > 0.05) and range of motion (p > 0.05) between the two conditions. Additionally, no asymmetries were detected between the lower limbs in both tests (p > 0.05).

CONCLUSIONS

The results of this pilot study indicate that using toe separators does not have an immediate effect on ankle range of motion and dynamic balance in young, healthy individuals. Future research should consider evaluating intervention programs of longer duration and exploring different populations.

The efficacy of shoes modification and orthotics in hallux valgus deformity: a comprehensive review of literature

Hallux valgus (HV) is a frequent forefoot deformity affecting about 23% of adults and 35.7% of people over 65. The exact etiology is not fully understood. The first ray plays a significant role in walking cause it bears the principal amount of weight and maintains the position of the medial arch. Several factors that deteriorate the integrality of the first ray, such as foot deformities, restrictive footwear, and pes planus, may be ascribed to the HV occurrence. Before any surgical correction, conservative treatment should always be initiated first. Currently, there is no consensus that conservative management by shoe modification and foot orthoses could correct the pathology or terminate the clinical worsening of the condition.From a careful analysis of the literature, proper footwear should be a shoe with an adequate length, wide toe box, cushioned sole, and a lowered heel to not increase the load on the metatarsal heads and cause pain. Personalized 3D printed customized toe spreaders may be applied in patients with HV, improving symptoms and bringing pain relief. Compensating the subtalar joint hyperpronation through foot orthoses plays a fundamental role in the HV development, preventing or at least controlling the condition's progress; this, along with weight reduction and regular physical activity.Data obtained suggest that dynamic foot orthoses prefer a biomechanical type with 3/4-length, which is less likely to negatively affect the dorsal or medial pressures, which instead were noted to increase with the sulcus- and full-length orthoses.Although some studies suggest that foot orthoses would favor the correction of HV deformity, results have been very variable and just in few studies appear to correct HV or reduce its progression, improving symptoms and bringing pain relief. In the case of HV surgical correction, orthoses seem to maintain the correct position acquired over time.

Additional effect of neuromuscular electrical stimulation in a conservative intervention on morphology and strength of abductor hallucis muscle and correction of hallux valgus deformity: a randomized controlled trial

BACKGROUND

In hallux valgus, morphological changes and functional weakness of intrinsic foot muscles occur, especially in the abductor hallucis muscle.

OBJECTIVES

This study aimed to investigate how a conservative treatment with the addition of neuromuscular electrical stimulation affects the volume and strength of the muscle, the correction of deformity, passive range of motion, pain, and disability.

METHODS

Twenty-eight female participants (48 feet) were randomly assigned to two groups. The interventions included orthoses and exercise (Ortho) in both groups. One group received additional neuromuscular electrical stimulation of abductor hallucis muscle to activate it. Each group received the treatments for one month and was assessed two times, at baseline before starting and after one month of treatment. Mixed within-between ANOVA, analysis of covariance, and nonparametric tests were used for data analysis.

RESULTS

The muscle volume, abduction strength, goniometric angle, and passive hallux dorsi/plantar flexion showed significant changes in both groups (p < .001). Subscales of the foot and ankle ability questionnaire, significantly changed (p ≤ .05). Pain decreased significantly in the two groups (p < .001 and p = .02). Intermetatarsal angle did not significantly differ between the two groups (p = .86, partial eta effect size = 0.001). But, the hallux valgus angle mean (on MRI) in the Ortho group was less than that of the orthoNMES group (p = .007, partial eta effect size = 0.15).

CONCLUSION

Both groups showed nearly identical treatment effects in the primary volume and hallux valgus correction outcome measures. In this study, adding neuromuscular electrical stimulation did not have an additional effect compared to conservative in the treatment of hallux valgus.

TRIAL REGISTRATION NUMBER

The RCT Code is IRCT20200915048725N1.

Comparison of abductor hallucis muscle activity in subjects with mild hallux valgus during three different foot exercises

BACKGROUND

Normal alignment of the foot is important because the feet support the body's weight. The intrinsic muscles of the foot mainly maintain the alignment and movement of the foot, whereas the abductor hallucis (AbdH) aligns the first metatarsophalangeal joint and maintains the medial longitudinal arch.

OBJECTIVE

This study was conducted to investigate the muscle activity of the AbdH and hallux valgus (HV) angle during three different foot exercises.

METHODS

Participants included 15 subjects aged 20-24 years with mild HV. All subjects performed three different foot exercises in random order: short foot exercise (SF), toe spread out exercise (TSO), and TSO with a pressure bio-feedback unit (TSOP). The muscle activity of the AbdH and the HV angle were measured during each foot exercise using surface electromyography and X-ray and then compared using one-way repeated-measures analysis of variance, followed by Bonferroni adjustment.

RESULTS

AbdH muscle activity differed significantly among SF, TSO, and TSOP. AbdH muscle activity was greater in TSOP (89.60%) than in SF (19.99%) and TSO (60.96%) (p= 0.006). The HV angle was significantly smaller in TSOP (15.72∘) than in SF (18.85∘) and TSO (16.81∘) (p= 0.001).

CONCLUSIONS

TSOP can be recommended as an effective AbdH strengthening exercise in subjects with mild HV.

Open vs Minimally Invasive Resection of the First Metatarsocuneiform Joint: An Anatomical Study

BACKGROUND

The modified Lapidus arthrodesis is a standard procedure to correct middle to severe hallux valgus (HV) deformities. Recently, minimally invasive techniques of first metatarsocuneiform joint (MCJ) resection using a Shannon burr were described. The primary goal of this study is to compare the anatomical efficacy and safety of first MCJ resection using a straight 2 × 13-mm Shannon burr and minimally invasive technique (MIS) vs an open technique using an oscillating saw.

METHODS

Ten pairs of fresh frozen cadaveric feet were randomly assigned to open or MIS first MCJ resection with subsequent systematic dissection. For the MIS procedure, a dorsomedial approach was used and for the open procedure a medioplantar approach was used. Cartilage removal was investigated by analyzing standardized scaled photographs of the resected articular surfaces with ImageJ software. Nearby structures at risk were analyzed for iatrogenic violation: tibialis anterior (TA), extensor hallucis longus (EHL) and peroneus longus (PL) tendons, and the Lisfranc ligament complex (LLC).

RESULTS

In the MIS group, the median cartilage resection was 85.9% at the cuneiform and 85.6% at the metatarsal bone compared to 100% cartilage resection in open technique (P < .01). Iatrogenic damage of the LLC, EHL, and TA tendons was not found in any group. The PL tendon was thinned out (<25% of tendon thickness) in 4 cases (40%) in the open group and in 1 case (10%) in the MIS group. A safe zone of 3.0 mm between the articular surface of the cuneiform bone and the LLC was identified, which can be resected without putting the LLC at risk when performing lateral-based wedge resections.

CONCLUSION

In this cadaver study with the procedures performed by an experienced foot and ankle surgeon, and using 2 different surgical approaches, we found general parity between the Shannon burr MIS technique vs oscillating saw open technique techniques with more risk to the PL with our open technique and approximately 15% less cartilage resection with our MIS technique.

LEVEL OF EVIDENCE

Level V, cadaver study.

Effects of custom insoles for symptomatic hallux valgus: protocol for a sham-controlled randomised trial

INTRODUCTION

Hallux valgus (HV) is one of the most prevalent forefoot deformities, and its frequency increases with age, reaching nearly 23% in adulthood (females are usually more affected). Studies on customised insoles and orthoses for HV showed inconclusive results. There is no consensus in literature regarding the ideal insole or length of use for pain relief or functional improvement in individuals with HV. This study will assess the effects of a customised insole with retrocapital bar associated with an infracapital bar of the first metatarsal on pain and function of individuals with symptomatic HV.

METHODS

This is the protocol for a blinded, sham-controlled randomised clinical trial. Eighty participants with symptomatic HV will be randomised into two groups (40 per group): customised insole or sham insole. Assessments will be performed at baseline (T0), six (T6) and 12 weeks (T12) of intervention. A follow-up will occur after 4 weeks of intervention (T16). The primary and secondary outcomes will be pain (Numerical Pain Scale) and function (Foot Function Index), respectively.

STATISTICAL ANALYSIS

Analysis of variance with a mixed design or Friedman's test will be considered according to data distribution; post-hoc analyses will be performed using Bonferroni test. Time × group interaction and within-group and between-group differences will also be assessed. The intent-to-treat analysis will be used. A significance level of 5% and 95% s will be adopted for all statistical analyses.

ETHICS AND DISSEMINATION

This protocol was approved by the research ethics committee of the Faculty of Health Sciences of Trairi/Federal University of Rio Grande do Norte (UFRN/FACISA; opinion number 5411306). The study results will be disseminated to participants, submitted to a peer-reviewed journal and presented in scientific meetings.

TRIAL REGISTRATIONS NUMBER

NCT05408156.

Minimally Invasive Surgery Using a Shannon Burr for the Treatment of Hallux Valgus Deformity: A Systematic Review

Background

Recently there has been an increase in minimally invasive surgery (MIS) for the correction of hallux valgus deformity. This systematic review aims to evaluate and present the current literature on MIS hallux valgus correction in studies reporting the use of the Shannon burr with distal metatarsal osteotomies to help establish evidence-based guidelines for surgeons using this technique.

Methods

Two independent authors performed a systematic literature search using the following databases: PubMed, Embase, and the Cochrane library. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol and the Cochrane Handbook guidelines were followed. All studies included were published from 2008 to 2022 and included the use of the Shannon burr during distal metatarsal osteotomies MIS for hallux valgus and at least 12-month follow-up. The MINORS score criteria was used to evaluate the strength and quality of 17 studies by 3 authors. Statistical analysis and meta-analysis were not performed because of the heterogeneity of the included studies and the data being descriptive.

Results

A total of 17 studies were reviewed. A total of 911 subjects were included, and 1088 MIS procedures were performed. The average follow-up was 23.8 (12-59.1) months. American Orthopaedic Foot & Ankle Society scale and visual analog scale scores improved from 52.1 (41-62.5) to 90.3 (83.3-97.1) and 4.9 (3-8.2) to 0.8 (0-1.9). Satisfaction rates were very high among the studies that reported it. The hallux valgus angle, intermetatarsal angle, and distal metatarsal articular angle improved from 31.4 (23.5-44.1) to 11.1 (7-17.2), 13.4 (8.1-18.6) to 7.3 (4.2-10.3), and 12.3 (9-16.3) to 4.1 (1-6.7), respectively. The complication rate was 16.6%, and recurrence was 2.2%. Nonunion comprised 0.4%, infections 1.1%, nerve injury 2.2%, avascular necrosis 0%, hallux varus 0.09%, transfer metatarsalgia 0.1%, and hardware removal 6.2%.

Conclusion

MIS for the treatment of hallux valgus using the Shannon burr appears to be a safe and effective therapy, with appropriate correction of the hallux valgus deformity, improvement in functional outcomes, high patient satisfaction, low recurrence, and acceptable complication rates.

Level of Evidence

Level II, systematic review.

Anteromedial Portal Technique, but Not Outside-in Technique, Is Superior to Standard Transtibial Technique in Knee Stability and Functional Recovery After Anterior Cruciate Ligament Reconstruction: A Network Meta-analysis

PURPOSE

To compare the postoperative outcomes of 4 different femoral drilling techniques in anterior cruciate ligament reconstruction.

METHODS

Three databases were searched for randomized controlled trials comparing any 2 or more of the following femoral drilling techniques in anterior cruciate ligament reconstruction: standard transtibial (sTT), anteromedial portal (AMP), outside-in (OI), or modified transtibial (mTT) technique. A Bayesian network meta-analysis was performed to assess postoperative stability and functional recovery in terms of the side-to-side difference (measured by arthrometry), Lachman test, pivot-shift test, International Knee Documentation Committee subjective and objective scores, Lysholm score, and Tegner score. The Fisher exact probability test and χ² test were used to compare the incidences of infection and graft rupture, respectively.

RESULTS

We included 20 randomized controlled trials involving 1,515 patients. The AMP technique showed a lower side-to-side difference (standardized mean difference, -0.33; 95% credible interval [CrI], -0.53 to -0.12), higher negative rate on the pivot-shift test (odds ratio, 2.19; 95% CrI, 1.38 to 3.44), and higher International Knee Documentation Committee objective score (odds ratio, 3.13; 95% CrI, 1.42 to 7.82) than the sTT technique. However, knee stability and functional outcomes did not differ significantly between the OI and sTT techniques. Safety outcomes of the mTT technique were unavailable. The incidence of graft rupture was 5.20% for the OI technique, 2.27% for the AMP technique, and 1.51% for the sTT technique. The OI technique had a significantly higher incidence of graft rupture than the sTT technique (χ² = 4.421, P = .035). No significant difference in the incidence of infection was found between the sTT, AMP, and OI techniques (P = .281).

CONCLUSIONS

The AMP technique, but not the OI technique, was superior to the sTT technique in knee stability and functional recovery. The OI technique had a higher incidence of graft rupture than the sTT technique. There was no significant difference between the AMP and OI techniques or between the mTT technique and any other femoral drilling technique.

LEVEL OF EVIDENCE

Level II, meta-analysis of Level I and II studies.

Selected hallmarks of hallux valgus in older women with symptomatic hallux valgus compared to middle-aged women with and without deformation of the forefoot

The aim of the study was to compare the shape of the feet, the mobility of the metatarsophalangeal and interphalangeal joints and the flexibility of the calf muscles in older women with hallux valgus versus middle-aged women with and without this deformation to identify the presence of features which correlate particularly strongly with hallux valgus, and on which prophylaxis and conservative treatment should focus. The study involved 201 women: 92 aged 60-84 years with hallux valgus of both toes, 78 aged 38-59 with hallux valgus of both toes, and 31 aged 38-57 years with correctly shaped feet. The intensity of pain in the foot, the valgus angle of the big toe and fifth toe, the longitudinal and transverse arches of the foot, the symmetry of foot load with body weight, toe joint mobility and muscle flexibility were analysed. Both groups of women with hallux valgus differed from women with normal feet in the height of the transverse arch, the extent of dorsal extension in the first metatarsophalangeal joint and plantar flexion in the first interphalangeal joint. Older women were additionally characterised by reduced plantar flexion in the metatarsophalangeal joint of the big toe, limited flexibility of the soleus and gastrocnemius muscles as well as less pain in the toe area than in the foot itself. The most characteristic changes which were observed in older women with hallux valgus are a limited range of motion in the MTP and IP joints of the big toe, a reduced transverse arch and increased restriction of calf muscle flexibility.

Effect of Displacement Degree of Distal Chevron Osteotomy on Metatarsal Stress: A Finite Element Method

BACKGROUND

The stress of foot bone can effectively evaluate the functional damage caused by foot deformity and the results of operation. In this study, the finite element method was used to investigate the degree of displacement of distal chevron osteotomy on metatarsal stress and metatarsophalangeal joint load; Methods: Four finite element models of displacement were established by using the CT images of a patient with moderate hallux valgus (hallux valgus angle and intermetatarsal angle were 26.74° and 14.09°, respectively), and the validity of the model was verified. Each finite element model consisted of bones and various cartilage structures, ligaments, and plantar fascia, as well as encapsulated soft tissue. Except for soft tissue, the material properties of other parts were isotropic linear elastic material, and the encapsulated soft tissue was set as nonlinear hyperelastic material. The mesh was tetrahedral mesh. Link elements were used in ligament and plantar fascia. A ground reaction force with a half-body weight was applied at the bottom of the floor to simulate the ground reaction when standing. The upper surfaces of the encapsulated soft tissue, distal tibia, and distal fibula were fixed. The stress distribution of metatarsals and the stress of cartilage of the first metatarsophalangeal joint were compared and analyzed; Results: Compared with the hallux valgus without osteotomy, the stress of the first metatarsals and second metatarsals of 2-4 mm decreased, and the stress of the interarticular cartilage of the first metatarsophalangeal joint with 4 mm was reduced. In the case of 6 mm, the stress value between the first metatarsal and the first metatarsophalangeal joint increased, and 4 mm was the most suitable distance; Conclusions: Compared with the hallux valgus without osteotomy, the stress of the first metatarsals and second metatarsals of 2-4 mm decreased, and the stress of the interarticular cartilage of the first metatarsophalangeal joint with 4 mm was reduced. In the case of 6 mm, the stress value between the first metatarsal and the first metatarsophalangeal joint increased, and 4 mm was the most suitable distance. For the degree of displacement of the distal chevron osteotomy, the postoperative stability and the stress distribution of metatarsal bone should be considered. Factors such as hallux valgus angle, intermetatarsal angle, patient's age, body weight, and metatarsal width should be considered comprehensively. The factors affecting osteotomy need to be further explored. The degree of displacement of osteotomy can be evaluated by FE method before the operation, and the most suitable distance can be obtained.

Seated Virtual Reality-Guided Exercise Improved Gait in a Postoperative Hallux Valgus Case

Virtual reality (VR)-guided exercise therapy using mediVR KAGURA has been reported to improve gait function by extending the arm to spatial targets while sitting. We aimed to investigate toe and trunk-pelvic function and plantar sensation during gait in a postoperative patient with hallux valgus. A 60-year-old woman, whose foot deformities had improved 6 months earlier, participated in the study. The exercise therapy interventions were performed twice weekly for 15 min. This study used an A-B-A design: 1-week pre-phase, 3-week intervention phase, and 2-week post-phase. The plantar pressure distribution and thoracic and pelvic displacements during gait were recorded at the end of each phase. The tactile pressure thresholds of the foot were determined before and after each exercise. The maximum force and impulse under the hallux increased after the intervention. The sensory threshold of the hallux was reduced. The amplitude of the thoracic and pelvic displacement was shortened in lateral and extended in the vertical and progressional directions after the intervention. We found that a 3-week VR-guided exercise improved toe function, plantar sensation, and postural adjustment of the trunk and pelvis during gait in a patient who had undergone surgery for hallux valgus, and the effects continued for 2 weeks.

Prevalence of chronic pain syndrome in patients who have undergone hallux valgus percutaneous surgery: a comparison of sciatic-femoral and ankle regional ultrasound-guided nerve blocks

Background

Chronic pain syndrome (CPS) is a common complication after operative procedures, and only a few studies have focused on the evaluation of CPS in foot-forefoot surgery and specifically on HV percutaneous correction. The objective of this study was to compare postoperative pain levels and incidence of CPS in two groups of patients having undergone femoral-sciatic nerve block or ankle block regional anaesthesia before hallux valgus (HV) percutaneous surgery and the association between postoperative pain levels and risk factors between these patient groups.

Methods

A consecutive patient series was enrolled and evaluated prospectively at 7 days, 1, 3 and 6 months after surgery. The participants were divided into two groups according to the regional anaesthesia received, femoral-sciatic nerve block or ankle block, and their outcomes were compared. The parameters assessed were postoperative pain at rest and during movement by the numerical rating scale (NRS), patient satisfaction using the Visual Analogue Scale (VAS), quality of life and return to daily activities. Statistical analysis was performed.

Results

One hundred fifty-five patients were assessed, 127 females and 28 males. Pain at rest (p < 0.0001) and during movement (p < 0.0001) significantly decreased during the follow-ups; at 6 months, 13 patients suffered from CPS. Over time, satisfaction remained stable (p > 0.05), quality of life significantly increased and patients returned to daily activities and work (p < 0.0001). No significant impact of type of anaesthesia could be detected. ASA 3 (p = 0.043) was associated to higher pain during movement; BMI (p = 0.005) and lumbago (p = 0.004) to lower satisfaction. No operative-anaesthetic complications were recorded. Postoperative pain at rest and during movement improved over time independently of the regional block used, with low incidence of CPS at last follow-up. Among risk factors, only a higher ASA was associated to higher pain during movement, while higher BMI and lumbago to lower satisfaction.

Conclusions

Both ultrasound-guided sciatic-femoral and ankle blocks were safe and effective in reducing postoperative pain with low incidence of CPS at last follow-up.

Trial registration

Clinical Trial NCT02886221. Registered 1 September 2016.