Objectives. The goals of this study were: 1) to determine if high-fat diet (HFD) feeding in female mice would negatively impact biomechanical and histologic consequences on the Achilles tendon and quadriceps muscle; and 2) to investigate whether exercise and branched-chain amino acid (BCAA) supplementation would affect these parameters or attenuate any negative consequences resulting from HFD consumption. Methods. We examined the effects of 16 weeks of 60% HFD feeding, voluntary exercise (free choice wheel running) and BCAA administration in female C57BL/6 mice. The Achilles tendons and quadriceps muscles were removed at the end of the experiment and assessed histologically and biomechanically. Results. HFD feeding significantly decreased the Achilles tendon modulus without histological alterations. BCAA administration significantly decreased the stiffness of Achilles tendons in the exercised normal diet mice. Exercise partially ameliorated both the weight gain and glucose levels in the HFD-fed mice, led to a significant decrease in the maximum load of the Achilles tendon, and an increase in the average fibril diameter of the quadriceps femoris muscle. There were significant correlations between body weight and several biomechanical properties, demonstrating the importance of controlling obesity for maintaining healthy tendon properties. . Conclusions. In summary, this study showed a significant impact of obesity and body weight on tendon biomechanical properties with limited effects of exercise and BCAAs. Cite this article: Bone Joint Res 2013;2:186–92

Lisfranc injuries were previously described as fracture-dislocations of the tarsometatarsal joints. With advancements in modern imaging, subtle Lisfranc injuries are now more frequently recognized, revealing that their true incidence is much higher than previously thought. Injury patterns can vary widely in severity and anatomy. Early diagnosis and treatment are essential to achieve good outcomes. The original classification systems were anatomy-based, and limited as tools for guiding treatment. The current review, using the best available evidence, instead introduces a stability-based classification system, with weightbearing radiographs and CT serving as key diagnostic tools. Stable injuries generally have good outcomes with nonoperative management, most reliably treated with immobilization and non-weightbearing for six weeks. Displaced or comminuted injuries require surgical intervention, with open reduction and internal fixation (ORIF) being the most common approach, with a consensus towards bridge plating. While ORIF generally achieves satisfactory results, its effectiveness can vary, particularly in high-energy injuries. Primary arthrodesis remains niche for the treatment of acute injuries, but may offer benefits such as lower rates of post-traumatic arthritis and hardware removal. Novel fixation techniques, including suture button fixation, aim to provide flexible stabilization, which theoretically could improve midfoot biomechanics and reduce complications. Early findings suggest promising functional outcomes, but further studies are required to validate this method compared with established techniques. Future research should focus on refining stability-based classification systems, validation of weightbearing CT, improving rehabilitation protocols, and optimizing surgical techniques for various injury patterns to ultimately enhance patient outcomes. Cite this article: Bone Joint J 2024;106-B(12):1431–1442

Aims. The optimal management of posterior malleolar ankle fractures, a prevalent type of ankle trauma, is essential for improved prognosis. However, there remains a debate over the most effective surgical approach, particularly between screw and plate fixation methods. This study aims to investigate the differences in outcomes associated with these fixation techniques. Methods. We conducted a comprehensive review of clinical trials comparing anteroposterior (A-P) screws, posteroanterior (P-A) screws, and plate fixation. Two investigators validated the data sourced from multiple databases (MEDLINE, EMBASE, and Web of Science). Following PRISMA guidelines, we carried out a network meta-analysis (NMA) using visual analogue scale and American Orthopaedic Foot and Ankle Score (AOFAS) as primary outcomes. Secondary outcomes included range of motion limitations, radiological outcomes, and complication rates. Results. The NMA encompassed 13 studies, consisting of four randomized trials and eight retrospective ones. According to the surface under the cumulative ranking curve-based ranking, the A-P screw was ranked highest for improvements in AOFAS and exhibited lowest in infection and peroneal nerve injury incidence. The P-A screws, on the other hand, excelled in terms of VAS score improvements. Conversely, posterior buttress plate fixation showed the least incidence of osteoarthritis grade progression, postoperative articular step-off ≥ 2 mm, nonunions, and loss of ankle dorsiflexion ≥ 5°, though it underperformed in most other clinical outcomes. Conclusion. The NMA suggests that open plating is more likely to provide better radiological outcomes, while screw fixation may have a greater potential for superior functional and pain results. Nevertheless, clinicians should still consider the fragment size and fracture pattern, weighing the advantages of rigid biomechanical fixation against the possibility of soft-tissue damage, to optimize treatment results. Cite this article: Bone Jt Open 2024;5(3):227–235

Aims

This cross-sectional study aimed to investigate the in vivo ankle kinetic alterations in patients with concomitant chronic ankle instability (CAI) and osteochondral lesion of the talus (OLT), which may offer opportunities for clinician intervention in treatment and rehabilitation.

Objectives. The aim of this study was to compare the biomechanical stability and clinical outcome of external fixator combined with limited internal fixation (EFLIF) and open reduction and internal fixation (ORIF) in treating Sanders type 2 calcaneal fractures. Methods. Two types of fixation systems were selected for finite element analysis and a dual cohort study. Two fixation systems were simulated to fix the fracture in a finite element model. The relative displacement and stress distribution were analysed and compared. A total of 71 consecutive patients with closed Sanders type 2 calcaneal fractures were enrolled and divided into two groups according to the treatment to which they chose: the EFLIF group and the ORIF group. The radiological and clinical outcomes were evaluated and compared. Results. The relative displacement of the EFLIF was less than that of the plate (0.1363 mm to 0.1808 mm). The highest von Mises stress value on the plate was 33% higher than that on the EFLIF. A normal restoration of the Böhler angle was achieved in both groups. No significant difference was found in the clinical outcome on the American Orthopedic Foot and Ankle Society Ankle Hindfoot Scale, or on the Visual Analogue Scale between the two groups (p > 0.05). Wound complications were more common in those who were treated with ORIF (p = 0.028). Conclusions. Both EFLIF and ORIF systems were tested to 160 N without failure, showing the new construct to be mechanically safe to use. Both EFLIF and ORIF could be effective in treating Sanders type 2 calcaneal fractures. The EFLIF may be superior to ORIF in achieving biomechanical stability and less blood loss, shorter surgical time and hospital stay, and fewer wound complications. Cite this article: M. Pan, L. Chai, F. Xue, L. Ding, G. Tang, B. Lv. Comparisons of external fixator combined with limited internal fixation and open reduction and internal fixation for Sanders type 2 calcaneal fractures: Finite element analysis and clinical outcome. Bone Joint Res 2017;6:433–438. DOI: 10.1302/2046-3758.67.2000640

Aims

The Cartiva synthetic cartilage implant (SCI) entered mainstream use in the management of first metatarsophalangeal joint (MTPJ) arthritis following the positive results of large trials in 2016. Limited information is available on the longer-term outcomes of this implant within the literature, particularly when independent from the originator. This single-centre cohort study investigates the efficacy of the Cartiva SCI at up to five years.

Aims

Arthroscopic microfracture is a conventional form of treatment for patients with osteochondritis of the talus, involving an area of < 1.5 cm². However, some patients have persistent pain and limitation of movement in the early postoperative period. No studies have investigated the combined treatment of microfracture and shortwave treatment in these patients. The aim of this prospective single-centre, randomized, double-blind, placebo-controlled trial was to compare the outcome in patients treated with arthroscopic microfracture combined with radial extracorporeal shockwave therapy (rESWT) and arthroscopic microfracture alone, in patients with ostechondritis of the talus.

Aims

A local injection may be used as an early option in the treatment of Morton’s neuroma, and can be performed using various medications. The aim of this study was to compare the effects of injections of hyaluronic acid compared with corticosteroid in the treatment of this condition.

Aims. The traditional transosseus flexor hallucis longus (FHL) tendon transfer for patients with Achilles tendinopathy requires two incisions to harvest a long tendon graft. The use of a bio-tenodesis screw enables a short graft to be used and is less invasive, but lacks supporting evidence about its biomechanical behaviour. We aimed, in this study, to compare the strength of the traditional transosseus tendon-to-tendon fixation with tendon-to-bone fixation using a tenodesis screw, in cyclical loading and ultimate load testing. Materials and Methods. Tendon grafts were undertaken in 24 paired lower-leg specimens and randomly assigned in two groups using fixation with a transosseus suture (suture group) or a tenodesis screw (screw group). The biomechanical behaviour was evaluated using cyclical and ultimate loading tests. The Student’s t-test was performed to assess statistically significant differences in bone mineral density (BMD), displacement, the slope of the load-displacement curves, and load to failure. Results. The screw group showed less displacement (loosening) during cyclical loading, which was significant during 300, 500, 600, 700, 800, 900, and 1000 cycles (p < 0.05: other cycles: 0.079 < p < 0.402). Compared with the suture group, the screw group had higher mean ultimate load values (133.6 N, . sd. 73.5 vs 110.1 N,. sd. 46.2; p = 0.416). Conclusion. Fixation of the FHL tendon with a tenodesis screw enables a less invasive procedure to be undertaken and shows similar biomechanical behaviour and primary strength compared with fixation using a transosseus suture. Cite this article: Bone Joint J 2018;100-B:1175–81

Aims. The purpose of this study was to analyse the biomechanics of walking, through the ground reaction forces (GRF) measured, after first metatarsal osteotomy or metatarsophalangeal joint (MTP) arthrodesis. Patients and Methods. A total of 19 patients underwent a Scarf osteotomy (50.3 years, standard deviation (. sd. ) 12.3) and 18 underwent an arthrodesis (56.2 years,. sd. 6.5). Clinical and radiographical data as well as the American Orthopaedic Foot and Ankle Society (AOFAS) scores were determined. GRF were measured using an instrumented treadmill. A two-way model of analysis of variance (ANOVA) was used to determine the effects of surgery on biomechanical parameters of walking, particularly propulsion. Results. Epidemiological, radiographical and clinical data were comparable in the two groups and better restoration of propulsive function was found after osteotomy as shown by ANOVA (two way: surgery × foot) with a surgery effect on vertical forces (p < 0.01) and a foot effect on anteroposterior impulse (p = 0.01). Conclusion. Patients who underwent Scarf osteotomy had a gait pattern similar to that of their non-operated foot, whereas those who underwent arthrodesis of the first (metatarsophalangeal) MTP joint did not totally recover the propulsive forces of the forefoot. Take home message: The main findings of this study were that after surgical correction for hallux valgus, patients who underwent scarf osteotomy had a gait pattern similar to that of their non-operated foot in terms of forefoot propulsive forces (Fz3, Iy2), whereas those who underwent arthrodesis of the first MTP joint had not. Cite this article: Bone Joint J 2016;98-B:641–6

Aims

The ideal management of acute syndesmotic injuries in elite athletes is controversial. Among several treatment methods used to stabilize the syndesmosis and facilitate healing of the ligaments, the use of suture tape (InternalBrace) has previously been described. The purpose of this study was to analyze the functional outcome, including American Orthopaedic Foot & Ankle Society (AOFAS) scores, knee-to-wall measurements, and the time to return to play in days, of unstable syndesmotic injuries treated with the use of the InternalBrace in elite athletes.

Charcot neuroarthropathy is a rare but serious complication of diabetes, causing progressive destruction of the bones and joints of the foot leading to deformity, altered biomechanics and an increased risk of ulceration. Management is complicated by a lack of consensus on diagnostic criteria and an incomplete understanding of the pathogenesis. In this review, we consider recent insights into the development of Charcot neuroarthropathy. It is likely to be dependent on several interrelated factors which may include a genetic pre-disposition in combination with diabetic neuropathy. This leads to decreased neuropeptides (nitric oxide and calcitonin gene-related peptide), which may affect the normal coupling of bone formation and resorption, and increased levels of Receptor activator of nuclear factor kappa-B ligand, potentiating osteoclastogenesis. Repetitive unrecognized trauma due to neuropathy increases levels of pro-inflammatory cytokines (interleukin-1β, interleukin-6, tumour necrosis factor α) which could also contribute to increased bone resorption, in combination with a pre-inflammatory state, with increased autoimmune reactivity and a profile of monocytes primed to transform into osteoclasts - cluster of differentiation 14 (CD14). Increased blood glucose and loss of circulating Receptor for Advanced Glycation End-Products (AGLEPs), leading to increased non-enzymatic glycation of collagen and accumulation of AGLEPs in the tissues of the foot, may also contribute to the pathological process. An understanding of the relative contributions of each of these mechanisms and a final common pathway for the development of Charcot neuroarthropathy are still lacking. Cite this article: S. E. Johnson-Lynn, A. W. McCaskie, A. P. Coll, A. H. N. Robinson. Neuroarthropathy in diabetes: pathogenesis of Charcot arthropathy. Bone Joint Res 2018;7:373–378. DOI: 10.1302/2046-3758.75.BJR-2017-0334.R1

It has been suggested that a supramalleolar osteotomy can return the load distribution in the ankle joint to normal. However, due to the lack of biomechanical data, this supposition remains empirical. The purpose of this biomechanical study was to determine the effect of simulated supramalleolar varus and valgus alignment on the tibiotalar joint pressure, in order to investigate its relationship to the development of osteoarthritis. We also wished to establish the rationale behind corrective osteotomy of the distal tibia. We studied 17 cadaveric lower legs and quantified the changes in pressure and force transfer across the tibiotalar joint for various degrees of varus and valgus deformity in the supramalleolar area. We assumed that a supramalleolar osteotomy which created a varus deformity of the ankle would result in medial overload of the tibiotalar joint. Similarly, we thought that creating a supramalleolar valgus deformity would cause a shift in contact towards the lateral side of the tibiotalar joint. The opposite was observed. The restricting role of the fibula was revealed by carrying out an osteotomy directly above the syndesmosis. In end-stage ankle osteoarthritis with either a valgus or varus deformity, the role of the fibula should be appreciated and its effect addressed where appropriate

Aims. In approximately 20% of patients with ankle fractures, there is an concomitant injury to the syndesmosis which requires stabilisation, usually with one or more syndesmotic screws. The aim of this review is to evaluate whether removal of the syndesmotic screw is required in order for the patient to obtain optimal functional recovery. Materials and Methods. A literature search was conducted in Medline, Embase and the Cochrane Library for articles in which the syndesmotic screw was retained. Articles describing both removal and retaining of syndesmotic screws were included. Excluded were biomechanical studies, studies not providing patient related outcome measures, case reports, studies on skeletally immature patients and reviews. No restrictions regarding year of publication and language were applied. Results. A total of 329 studies were identified, of which nine were of interest, and another two articles were added after screening the references. In all, two randomised controlled trials (RCT) and nine case-control series were found. The two RCTs found no difference in functional outcome between routine removal and retaining the syndesmotic screw. All but one of the case-control series found equal or better outcomes when the syndesmotic screw was retained. However, all included studies had substantial methodological flaws. Conclusions. The currently available literature does not support routine elective removal of syndesmotic screws. However, the literature is of insufficient quality to be able to draw definitive conclusions. Secondary procedures incur a provider and institutional cost and expose the patient to the risk of complications. Therefore, in the absence of high quality evidence there appears to be little justification for routine removal of syndesmotic screws. Cite this article: Bone Joint J 2016;98-B:1497–1504

Aims. Fractures of the navicular can occur in isolation but, owing to the intimate anatomical and biomechanical relationships, are often associated with other injuries to the neighbouring bones and joints in the foot. As a result, they can lead to long-term morbidity and poor function. Our aim in this study was to identify patterns of injury in a new classification system of traumatic fractures of the navicular, with consideration being given to the commonly associated injuries to the midfoot. Patients and Methods. We undertook a retrospective review of 285 consecutive patients presenting over an eight- year period with a fracture of the navicular. Five common patterns of injury were identified and classified according to the radiological features. Type 1 fractures are dorsal avulsion injuries related to the capsule of the talonavicular joint. Type 2 fractures are isolated avulsion injuries to the tuberosity of the navicular. Type 3 fractures are a variant of tarsometatarsal fracture/dislocations creating instability of the medial ray. Type 4 fractures involve the body of the navicular with no associated injury to the lateral column and type 5 fractures occur in conjunction with disruption of the midtarsal joint with crushing of the medial or lateral, or both, columns of the foot. Results. In order to test the reliability and reproducibility of this new classification, a cohort of 30 patients with a fracture of the navicular were classified by six independent assessors at two separate times, six months apart. Interobserver reliability and intraobserver reproducibility both had substantial agreement, with kappa values of 0.80 and 0.72, respectively. Conclusion. We propose a logical, all-inclusive, and mutually exclusive classification system for fractures of the navicular that gives associated injuries involving the lateral column due consideration. We have shown that this system is reliable and reproducible and have described the rationale for the subsequent treatment of each type. Cite this article: Bone Joint J 2018;100-B:176–82

Lengthening of the conjoined tendon of the gastrocnemius aponeurosis and soleus fascia is frequently used in the treatment of equinus deformities in children and adults. The Vulpius procedure as described in most orthopaedic texts is a division of the conjoined tendon in the shape of an inverted V. However, transverse division was also described by Vulpius and Stoffel, and has been reported in some clinical studies. We studied the anatomy and biomechanics of transverse division of the conjoined tendon in 12 human cadavers (24 legs). Transverse division of the conjoined tendon resulted in predictable, controlled lengthening of the gastrocsoleus muscle-tendon unit. The lengthening achieved was dependent both on the level of the cut in the conjoined tendon and division of the midline raphé. Division at a proximal level resulted in a mean lengthening of 15.2 mm (. sd . 2.0, (12 to 19), which increased to 17.1 mm (. sd . 1.8, (14 to 20) after division of the midline raphé. Division at a distal level resulted in a mean lengthening of 21.0 mm (. sd. 2.0, (18 to 25), which increased to 26.4 mm (. sd . 1.4, (24 to 29) after division of the raphé. These differences were significant (p < 0.001). Cite this article: Bone Joint J 2014; 96-B:778–82

Aims

In the context of tendon degenerative disorders, the need for innovative conservative treatments that can improve the intrinsic healing potential of tendon tissue is progressively increasing. In this study, the role of pulsed electromagnetic fields (PEMFs) in improving the tendon healing process was evaluated in a rat model of collagenase-induced Achilles tendinopathy.

Introduction. The aetiology of hallux valgus is almost certainly multifactoral. The biomechanics of the first ray is a common factor to most. There is very little literature examining the anatomy of the proximal metatarsal articular surface and its relationship to hallux valgus deformity. Methods. We examined 42 feet from 23 specimens in this anatomical dissection study. Results. This analysis revealed three distinct articular subtypes. Type 1 had one single facet, type 2 had two distinct articular facets, and type 3 had three articular facets one of which was a lateral inferior facet elevated from the first. Type 1 joints occurred exclusively in the hallux valgus specimens, while type 3 joints occurred exclusively in normal specimens. Type 2 joints occurred in both hallux valgus and normal specimens. Another consistent finding in regards to the proximal articular surface of the first metatarsal was the lateral plantar prominence. This prominence possessed its own articular surface in type 3 joints and was significantly flatter in specimens with hallux valgus (p < 0.001) and the angle with the joint was significantly more obtuse (p < 0.001). Conclusions. We believe the size and acute angle of this prominence gives structural mechanical impedance to movement at the tarsometatarsal joint and thus improves the stability

Aims

Functional rehabilitation has become an increasingly popular treatment for Achilles tendon rupture (ATR), providing comparably low re-rupture rates to surgery, while avoiding risks of surgical complications. Limited evidence exists on whether gap size should affect patient selection for this treatment option. The aim of this study was to assess if size of gap between ruptured tendon ends affects patient-reported outcome following ATR treated with functional rehabilitation.

Objective. The objective of this study was to evaluate the rotation and translation of each joint in the hindfoot and compare the load response in healthy feet with that in stage II posterior tibial tendon dysfunction (PTTD) flatfoot by analysing the reconstructive three-dimensional (3D) computed tomography (CT) image data during simulated weight-bearing. . Methods. CT scans of 15 healthy feet and 15 feet with stage II PTTD flatfoot were taken first in a non-weight-bearing condition, followed by a simulated full-body weight-bearing condition. The images of the hindfoot bones were reconstructed into 3D models. The ‘twice registration’ method in three planes was used to calculate the position of the talus relative to the calcaneus in the talocalcaneal joint, the navicular relative to the talus in talonavicular joint, and the cuboid relative to the calcaneus in the calcaneocuboid joint. Results. From non- to full-body-weight-bearing condition, the difference in the talus position relative to the calcaneus in the talocalcaneal joint was 0.6° more dorsiflexed (p = 0.032), 1.4° more everted (p = 0.026), 0.9 mm more anterior (p = 0.031) and 1.0 mm more proximal (p = 0.004) in stage II PTTD flatfoot compared with that in a healthy foot. The navicular position difference relative to the talus in the talonavicular joint was 3° more everted (p = 0.012), 1.3 mm more lateral (p = 0.024), 0.8 mm more anterior (p = 0.037) and 2.1 mm more proximal (p = 0.017). The cuboid position difference relative to the calcaneus in the calcaneocuboid joint did not change significantly in rotation and translation (all p ≥ 0.08). . Conclusion. Referring to a previous study regarding both the cadaveric foot and the live foot, joint instability occurred in the hindfoot in simulated weight-bearing condition in patients with stage II PTTD flatfoot. The method used in this study might be applied to clinical analysis of the aetiology and evolution of PTTD flatfoot, and may inform biomechanical analyses of the effects of foot surgery in the future. Cite this article: Bone Joint Res 2013;2:255–63