Early Radiological Outcome of MIS Bunionectomy With Guided Trajectory System
Auteurs
Victor Dubois-Ferrière & Antoine Acker & Lisca Drittenbass, M.D. & Mathieu Assal & Laura Peurière, PhD & Elisabeth Schauer
Année
2025
Abstract
Early radiologic outcome and technical details of MIS
bunionectomy using a guided trajectory system is reported here.
From April 2022 to March 2023, 20 consecutive minimally invasive
bunionectomies were performed on 17 female patients (bilateral in 3
patients) with an average age of 63.6 (range: 46 to 82). The mean
IMA improved from 14.3 degrees (SD: 3.2) to 4.6 degrees (SD: 2.0),
HVA from 28.2 degrees (SD: 6.3) to 6.7 degrees (SD: 2.8), DMAA
from 16.6 degrees (SD: 5.6) to 6.6 degrees (SD: 1.8). Preoperatively,
17 feet (89.5%) were in TSP grades 2 and 3. Postoperatively, 19 feet
(95%) improved to either TSP grades 0 and 1. The mean duration of
operative time was 50 (SD: 9.25, range: 23 to 65) minutes. No
intraoperative complications were reported. Overall, this study
provides valuable insights into the benefits of using a guided trajectory
system to improve the success of bunion correction surgeries.
Level of evidence: Level 4.
A Hallux Valgus Surgical Planning Survey Using WBCT-based 3D Printing
Auteurs
Antoine Acker
Année
2025
Abstract
Background: Recent literature highlights the importance of treating hallux valgus (HV) as a 3-dimensional (3D) deformity.
Although 3D printing may enhance visualization of the multiplanar aspects of HV, its influence on surgical planning remains unclear. This study assessed changes in surgical plans when surgeons sequentially reviewed 2D radiographs, 3D weightbearing computed tomography (WBCT), and 3D-printed models, hypothesizing that 3D printing would have the greatest impact.
Methods: A single HV case (a 40-year-old woman, intermetatarsal angle [IMA] 21 degrees, HV angle [HVA] 47 degrees) was evaluated by 30 surgeons in a masked, stepwise manner. Surgical plans were recorded at each stage. Surgeons rated the influence of WBCT and 3D printing using a 5-point Likert scale. A follow-up survey examined the effect of these technologies on correction amplitudes.
Results: The participants were mostly early career surgeons (median age 35.5 years, 2 years in practice). WBCT was accessible to 43.3% and used in 30% of HV cases, whereas 3D printing was accessible to 23.3% and used in 6.6%. Changes in the treatment algorithm occurred in 30% of cases after WBCT and in 43.3% after 3D printing. Significant differences (P < .05) were observed for the Lapicotton procedure between radiography and WBCT, and between WBCT and 3D printing. Surgeons performing <50 HV cases annually or with >70% Foot and Ankle specialization were more influenced by WBCT. Follow-up data (n = 23) indicated that WBCT and 3D printing influenced correction amplitudes, particularly for pronation and distal metatarsal articular angle (DMAA), more than for the IMA.
Discussion: Both WBCT and 3D printing influenced surgical planning, mostly explained by changes in first ray tarsometatarsal procedures. The rotational components (pronation and DMAA) were perceived as the most significantly affected. Future studies should explore cost-effectiveness, patient outcomes, and the utility of combining WBCT and 3D
printing in other deformities requiring multiplanar corrections.
Level of Evidence: Level IV, cross-sectional survey.
Foot Malalignment and Proximal Fifth Metatarsal Fractures
Auteurs
Antoine Acker
Année
2025
Abstract
Background: Proximal fifth metatarsal fractures are common injuries that are classified into 3 zones according to their anatomical localization. While zone 1 and 2 fractures typically are traumatic, zone 3 fractures may be linked to foot alignment abnormalities, such as hindfoot varus and metatarsus adductus. The aim of the study was to explore the association between hindfoot alignment and different fracture zones, as well as the relationship between traumatic and atraumatic fracture origin and foot alignment.
Methods: We conducted a retrospective cohort study of patients with proximal fifth metatarsal fractures who had received a weightbearing computed tomography (WBCT) scan. Feet with zone 1 and 2 fractures were compared to zone 3
fractures and a healthy control group. Additionally, we compared feet with a traumatic fracture origin with those without.
Foot alignment parameters, including the foot and ankle offset (FAO) and the forefoot arch angle (FAA), were analyzed alongside data from semiautomated segmentation reports. P <.05 was considered significant.
Results: The study included 45 fractures (23 zone 1 and 2, 22 zone 3) and 19 controls. Zone 3 fractures showed a significant association with higher body mass index (P < .01), hindfoot varus (P < .01), and metatarsus adductus (P < .01) compared with zone 1 and 2 fractures, and they more frequently had a nontraumatic origin (P < .01). Zone 3 fractures also showed a significantly higher transverse arch (P < .01). No differences have been observed between zone 1 and 2 fractures and the controls. Fractures with atraumatic origin were significantly associated with hindfoot varus (P < .01), metatarsus adductus (P < .01), hindfoot varus (P < .01), and metatarsus adductus (P < .01).
Conclusion: Hindfoot varus, metatarsus adductus, and a high transverse arch were significantly associated with zone 3 fractures as well as fractures with atraumatic origin.
Long-term Clinical Outcomes After Syndesmosis Fixation With K-wires in Ankle Fractures With Syndesmotic Instability
Auteurs
Victor Dubois-Ferrière & Filippo Pierobon
Année
2025
Abstract
Background: Syndesmotic instability is a significant concern in the management of unstable ankle fractures, occurring
in approximately 10% to 13% of these cases. Early recognition and stabilization of syndesmotic injuries are essential to
ensure optimal long-term outcomes. Several techniques are currently in use, often involving complex procedure and/or
costly devices. Our study presents a syndesmosis fixation technique using K-wires that is both simple and cost-effective.
Methods: This is a retrospective single-center case series. Three hundred seventy-seven ankle fractures with intraoperative
syndesmosis instability and subsequent syndesmosis fixation with a K-wire were treated between 2002 and 2012. Of the
377 patients, 51 died and we were able to obtain long-term questionnaire completions from 94 patients (29% of presumed
living patients), with a mean follow-up of 10.6 ± 3.0 years.
Results: The mean age was 46.6 ± 18.5 years; 42% were Danis-Weber type B and 58% type C fractures. Syndesmosis
fixation failure was observed in 9 (2%) patients, and 5 (1%) patients had K-wire displacement without loss of syndesmosis
reduction. The Manchester-Oxford Foot Questionnaire (MOXFQ) was obtained 10±3 years after surgery. The mean
MOXFQ pain score was 25.9 ± 25.4, the mean functional score was 18 ± 24.8, and the mean social score was 13.7 ± 22.2.
Conclusion: We report long-term (10.6 ± 3 years) functional outcomes using a validated patient-reported questionnaire
in patients who underwent syndesmosis fixation with 2 K-wires for unstable ankle fractures. In the subset of patients we
were able to find in follow-up, we found low rates of syndesmosis fixation failure, low pain scores, and excellent functional
outcomes. The availability and low cost of these implants make this technique an accessible and cost-effective solution to
consider for syndesmosis fixation.
Level of Evidence: Level IV, retrospective case series.
A Comprehensive Weightbearing Computed Tomography Study on Patients With Hallux Valgus: Exploring Multiplanar Deformity Interrelationships
Auteurs
Antoine Acker
Année
2025
Abstract
Background: Hallux valgus (HV) is a complex, multiplanar deformity. In this study, we examined the interrelationships
between various components of this deformity using weightbearing computed tomography (WBCT). We hypothesized
that the severity of traditional axial plane deformities would correlate with malpositioning of the metatarsosesamoid
complex, first-ray coronal rotational deformity, and malalignment of the hindfoot and midfoot. The findings may offer
valuable insights for guiding the correction of HV deformities.
Methods: Patients with an HV angle greater than 15 degrees who underwent WBCT were included. Traditional
2-dimensional parameters were semiautomatically assessed. Manual measurements included hindfoot and midfoot WBCT
parameters, for example, foot and ankle offset, talar posterior and middle facet morphology, and forefoot arch angle.
First-ray parameters, including first metatarsal rotation, sesamoid rotation angle, hallucal pronation angle, and sesamoid
position, were measured using established methods. Patients were categorized by hindfoot moment arm values to evaluate
hindfoot-forefoot relationships.
Results: Sixty-eight feet (53 patients) were included. Manual measurements exhibited excellent interobserver reliability,
with ICCs of 0.845 to 0.987 and a kappa coefficient of 0.899 for the sesamoid position. The mean HV angle was 27.4 ± 7.8
degrees, whereas the mean IM angle was 15.8 ± 3.5 degrees. Significant correlations were observed between the HV
and intermetatarsal (IM) angles, with all metatarsosesamoid complex parameters and first-ray coronal plane rotational
parameters distal to the metatarsal head. The axial and sagittal talar–first metatarsal angles correlated with the HV angle
but not with the IM angle. Significant differences in the HV angle, sagittal first tarsal–metatarsal joint angle, and first
metatarsal head rotation were observed between the hindfoot moment arm groups, as confirmed by post hoc analysis.
Conclusion: The findings support our hypothesis, identifying significant correlations between metatarsosesamoid complex
malposition, distal first-ray coronal pronation, and traditional axial plane deformities in HV. Some hindfoot–midfoot
alignments correlated with the HV angle but not with the IM angle.
Comparative Analysis of Structural Differences in Progressive Collapsing Foot Deformity With and Without Hallux Valgus
Auteurs
Antoine Acker
Année
2024
Abstract
Background: Progressive collapsing foot deformity (PCFD) and hallux valgus (HV) are complex 3-dimensional deformities
of the foot. This study aimed to investigate structural and alignment differences between PCFD with and without HV using
weightbearing computed tomography.
Methods: Patients with PCFD aged 18 years or older who underwent weightbearing computed tomography were
consecutively enrolled. Standard 2-dimensional PCFD and HV parameters were assessed semiautomatically. Foot and ankle
offset, forefoot arch angle, and pronation of the medial column bones in the coronal plane, with the ground as a reference,
were manually measured. Additionally, the angles from the inferior aspect of subtalar posterior facet of the talus to the
ground (subtalar horizontal angle), from the inferior (posterior facet) to superior facets of the talus (infratalar-supratalar
angle), and from the inferior (posterior facet) of the talus to the superior facet of the calcaneus (infratalar-supracalcaneal
angle) were examined. HV deformity was defined by an HV angle of ≥15 degrees.
Results: Among 72 feet (58 patients) studied, 33 displayed HV, whereas 39 did not. In the coronal plane, the PCFD
with HV group showed a higher infratalar-supratalar angle and greater pronation at the first tarsometatarsal joint, first
metatarsal bone, and head. The PCFD with HV group also exhibited greater naviculocuneiform joint supination. Generalized
estimating equation logistic regression analysis revealed significant associations of HV deformity with the intrinsic rotation
of the first metatarsal bone (P < .001), infratalar-supratalar angle (P = .004), and rotation of the first tarsometatarsal joint
(P < .001).
Conclusion: This study confirmed significant structural and alignment differences between PCFD with and without
HV. Notably, the infratalar-supratalar angle, rotation of the first tarsometatarsal joint, and intrinsic rotation of the first
metatarsal bone were associated with HV deformity.
Level of Evidence: Level III, retrospective comparative study.
Progressive First Metatarsal Shortening Is Observed Following Dermal Allograft Interpositional Arthroplasty in Hallux Rigidus: Short Report
Auteurs
Antoine Acker
Année
2024
Abstract
Background: The main goal of this study was to evaluate postoperative changes in the length of the first metatarsal
(M1) and the proximal phalanx of the hallux (P1) after acellular dermal allograft interpositional arthroplasty (ADAIPA).
We hypothesized that there would be a shortening of the first ray at the first metatarsal, the proximal phalanx,
or both.
Methods: In this retrospective study, we assessed patients who underwent ADA-IPA between 2019 and 2022. On
standing anteroposterior (AP) foot radiographs, we measured first metatarsal (M1), second metatarsal (M2), proximal
phalanx (P1), and the entire hallux (HX) lengths. M1/M2 and P1/HX ratios were calculated. The first metatarsophalangeal
joint space was calculated. All measurements were recorded preoperatively, at 6 weeks postoperatively, and at final
follow-up.
Results: The pilot study included 11 patients. At final follow-up, we found shortening of M1 and P1 in comparison to
the preoperative length, as evidenced by lower M1/M2 (82.6 ± 2.3 vs 75.4 ± 5.1; P = .001) and P1/HX ratios (53.4 ± 2.3 vs
48.9 ± 7.9; P = .001). Follow-up length was negatively correlated with M1/M2 (r = −0.76, P = .003).
Conclusion: ADA-IPA might be associated with shortening of both first metatarsal and proximal phalanx, with the former
showing progressive shortening.
Level of Evidence: Level IV, retrospective case series.
Hallux rigidus is a degenerative arthritic condition affecting the first metatarsophalangeal
(MTP) joint. This condition results in reduced joint mobility, pain, and the development
of osteophytes. It ranks as the second most common ailment targeting the
first MTP joint after hallux valgus and stands as the predominant form of arthritis in
the foot.1,2 Women are more prone to this condition than men, and it often manifests
bilaterally.1,2 Many patients, before seeking professional medical intervention,
attempt to alleviate symptoms using nonsteroidal anti-inflammatory drugs, but as
the disease advances, these methods generally prove ineffective.3 Initial treatments
usually lean toward conservative approaches, resorting to surgical methods when
conservative measures fail.3 There is a wide array of surgical options available,
ranging from joint arthrodesis to joint-sparing techniques such as osteotomies or replacements.
4,5 Each option has utility based on the desired outcomes and patientspecific
characteristics.
Antoine Acker & Kepler Alencar Mendes de Carvalho, MD; Andrew E. Hanselman, MD
Année
2023
Abstract
Summary: There is a place for initial conservative treatment in most patients with hallux rigidus, understanding that there are limitations. These treatment options should be recommended in a tailored fashion based on patients’ expectations and clinical and radiological findings. There is clearly a consensus that no conservative treatment can limit the degenerative evolution of the disease. Patients with a tolerable pain level may find a stabilization of their pain with conservative measures, despite
Subtalar Arthrodesis in Patients With Prior Tibiotalar Arthrodesis for Posttraumatic Osteoarthritis
Auteurs
Nils Reymond & Laetitia Theunissen, MD; Paul-André Deleu, PhD; Ivan Birch, PhD; Bernhard Devos Bevernage, MD; Pierre Maldague, MD; Vincent Gombault, MD; Corentin Malherbe, MD; Thibaut Leemrijse, MD
Année
2023
Abstract
Background: The tibiotalar arthrodesis for end-stage ankle osteoarthritis is a surgical procedure that leads to a modification of the kinematics of the adjacent joints and may result in the development of secondary osteoarthritic degeneration of the subtalar joint. It has previously been observed that subtalar arthrodesis in this context shows a lower fusion rate than isolated subtalar arthrodesis. This retrospective study reports the results of subtalar joint arthrodesis with previous ipsilateral tibiotalar arthrodesis and suggests some factors that may compromise the fusion of the joint.
Methods: Between September 2010 and October 2021, 15 arthrodeses of the subtalar joint with screw fixation were performed in 14 patients, with a fusion of the ipsilateral tibiotalar joint. Fourteen of 15 cases used an open sinus tarsi approach, 13 were augmented with iliac crest bone graft, and 11 had supplemental demineralized bone matrix (DBM). The outcome variables were fusion rate, time to fusion, and revision rate. Fusion was assessed by radiographs and computed tomography scan.
Results: Twelve of the 15 subtalar arthrodeses (80%) fused at the first attempt with an average fusion time of 4.7 months.
Conclusion: In this limited retrospective case series, compared to the fusion rate of isolated subtalar arthrodesis reported in the literature, the rate of subtalar fusion in the presence of an ipsilateral tibiotalar arthrodesis was found to be lower.
Level of Evidence: Level IV, retrospective case series.
Articular Cartilage Repair After Implantation of Hyaline Cartilage Beads Engineered From Adult Dedifferentiated Chondrocytes: Cartibeads Preclinical Efficacy Study in a Large Animal Model
Articular Cartilage Repair After Implantation of Hyaline Cartilage Beads Engineered From Adult Dedifferentiated Chondrocytes: Cartibeads Preclinical Efficacy Study in a Large Animal Model
Auteurs
Halah Kutaish-Stern & Mathieu Assal
Année
2023
Abstract
Background: Chondrocyte-based cell therapy to repair cartilage has been used for >25 years despite current limitations. This work presents a new treatment option for cartilage lesions.Hypothesis: High-quality hyaline cartilage microtissues called Cartibeads are capable of treating focal chondral lesions once implanted in the defect, by complete fusion of Cartibeads among themselves and their integration with the surrounding native cartilage and subchondral bone.
Study design: Controlled laboratory study.
Methods: Cartibeads were first produced from human donors and characterized using histology (safranin O staining of glycosaminoglycan [GAG] and immunohistochemistry of collagen I and II) and GAG dosage. Cartibeads from 6 Göttingen minipigs were engineered and implanted in an autologous condition in the knee (4 or 5 lesions per knee). One group was followed up for 3 months and the other for 6 months. Feasibility and efficacy were measured using histological analysis and macroscopic and microscopic scores.
Results: Cartibeads revealed hyaline features with strong staining of GAG and collagen II. High GAG content was obtained: 24.6-µg/mg tissue (wet weight), 15.52-µg/mg tissue (dry weight), and 35 ± 3-µg GAG/bead (mean ± SD). Histological analysis of Göttingen minipigs showed good integration of Cartibeads grafts at 3 and 6 months after implantation. The Bern Score of the histological assay comparing grafted versus empty lesions was significant at 3 months (grafted, n = 10; nongrafted, n = 4; score, 3.3 and 5.3, respectively) and 6 months (grafted, n = 11; nongrafted, n = 3; score, 1.6 and 5.1).
Conclusion: We developed an innovative 3-step method allowing, for the first time, the use of fully dedifferentiated adult chondrocytes with a high number of cell passage (owing to the extensive amplification in culture). Cartibeads engineered from chondrocytes hold potential as an advanced therapy medicinal product for treating cartilage lesions with established efficacy.
Clinical relevance: This successful preclinical study, combined with standardized manufacturing of Cartibeads according to good manufacturing practice guidelines, led to the approval of first-in-human clinical trial by the ethics committee and local medical authority. The generated data highlighted a promising therapy to treat cartilage lesions from a small amount of starting biopsy specimen. With our innovative cell amplification technology, very large lesions can be treated, and older active patients can benefit from it.