Introduction. Charcot neuroarthropathy is a limb threatening condition and the optimal surgical strategy for limb salvage in gross foot deformity remains unclear. We present our experience of using fine wire frames to correct severe midfoot deformity, followed by internal beaming to maintain the correction. Materials and Methods. Nine patients underwent this treatment between 2020–2023. Initial deformity correction by Ilizarov or hexapod butt frame was followed by internal beaming with a mean follow up of 11 months. A retrospective analysis of radiographs and electronic records was performed. Meary's angle, calcaneal pitch, cuboid height, hindfoot midfoot angle and AP Meary's angle were compared throughout treatment. Complications, length of stay and the number of operations are also described. Results. Mean age was 53 years (range:40–59). Mean frame duration was 3.3 months before conversion to beaming. Prior frame-assisted deformity correction resulted in consistently improved radiological parameters. Varying degrees of subsequent collapse were universal, but 5 patients still regained mobility and a stable, plantargrade, ulcer-free foot. Complications were common, including hardware migration (N=6,66%), breakage (N=2,22%), loosening (N=3,33%), infection (N=4,44%), 1 amputation and an unscheduled reoperation rate of 55%. Mean cumulative length of stay was 42 days. Conclusions. Aggressive deformity correction and internal fixation for Charcot arthropathy requires strategic and individualised care plans. Complications are expected for each patient. Patients must understand this is a limb salvage scenario. This management strategy is resource heavy and requires timely interventions at each stage with a well-structured MDT delivering care. The departmental learning points are to be discussed

Aim. The aim of this paper is to analyse the cause of neuropathic diabetic foot ulcers and discuss their preventive measures. Methods. Review of patients with foot ulcers managed in our diabetic MDT clinics since Feb 2018 were analysed. Based on this observation and review of pertinent literature, following observations were made. Results. Forefoot. Progressive hindfoot equinus from contraction of gastroc-soleus-tendo-Achilles complex, with additional contraction of tibialis posterior and peroneal longus muscles and, progressive plantar flexed metatarsal heads secondary to claw toe deformity results in increased forefoot plantar pressures. In patients with insensate feet, this result in ulcer formation under the metatarsal heads from shear stress when walking. Callosity under the metatarsal heads is the earliest clinical sign. Most patients by this time have fixed tightness of the muscle groups as assessed by negative Silfverskiold test. Percutaneous tendo-Achilles lengthening (TAL) has shown to reduce the mid-forefoot plantar pressures by 32% and ulcer healing in 96% of patients within 10 weeks (± 4 weeks). Additional z-lengthening of peroneal longus and tibialis posterior tendons helped in patients with big-toe and 5. th. metatarsal head ulcers. Proximal metatarsal osteotomies further reduce the forefoot pressures to near normality. Midfoot. Midfoot ulcers are secondary to rocker-bottom deformity a consequence of Charcot neuroarthropathy (CN). Hindfoot equinus as described and relative osteopenia from neurally mediated increased blood flow (neurovascular theory) and repeated micro-trauma (neurotraumatic theory) result in failure of medial column osseo-ligamentous structures. As the disease progress to the lateral column, the cuboid height drops resulting in a progressive rocker bottom deformity. The skin under this deformity gradually breaks down to ulceration. In the pre-ulcerative stages of midfoot CN, TAL has shown to stabilise the disease progression and in some patents’ regression of the disease process was noted. The lump can excised electively and the foot accommodated in surgical shoes. Hindfoot. These develop commonly at the pressure areas and bony exostosis in non-ambulatory patients. In ambulatory patients, the most common cause are factors that result in over lengthening of tendo-Achilles such as after TAL, spontaneous tears, or tongue-type fractures. Conclusions. Early identification of factors that result in plantar skin callosity and treating the deforming forces prevent progression to ulceration. Total contact cast without treatment of these deforming forces results in progression of these callosities to ulceration while in the cast or soon after completion of cast treatment

The detailed biomechanical mechanism of annulus fibrosus under abnormal loading is still ambiguous, especially at the micro and nano scales. This study aims to characterize the alterations of modulus at the nano scale of individual collagen fibrils in annulus fibrosus after in-situ immobilization, and the corresponding micro-biomechanics of annulus fibrosus. An immobilization model was used on the rat tail with an external fixation device. Twenty one fully grown 12-week-old male Sprague-Dawley rats were used in this study. The rats were assigned to one of three groups randomly. One group was selected to be the baseline control group with intact intervertebral discs (n=7). In the other two groups, the vertebrae were immobilized with an external fixation device that fixed four caudal vertebrae (C7-C10) for 4 and 8 weeks, respectively. Four K-wires were fixed in parallel using two aluminum alloy cuboids which do not compress or stretch the target discs. The immobilized discs were harvested and then stained with hematoxylin/eosin, scanned using atomic force microscopy to obtain the modulus at both nano and micro scales, and analyzed the gene expression with real-time quantitative polymerase chain reaction. Significance of differences between the study groups was obtained using a two-way analysis of variance (ANOVA) with Fisher's Partial Least-Squares Difference (PLSD) to analyze the combined influence of immobilization time and scanning region. Statistical significance was set at P≤0.05. Compared to the control group, the inner layer of annulus fibrosus presented significant disorder and hyperplasia after immobilization for 8 weeks, but not in the 4 week group. The fibrils in inner layer showed an alteration in elastic modulus from 91.38±20.19MPa in the intact annulus fibrosus to 110.64±15.58MPa (P<0.001) at the nano scale after immobilization for 8 weeks, while the corresponding modulus at the micro scale also underwent a change from 0.33±0.04MPa to 0.47±0.04MPa (P<0.001). The upregulation of collagen II from 1±0.03 in control to 1.22±0.03 in 8w group (P = 0.003) was induced after immobilization, while other genes expression showed no significant alteration after immobilization for both 4 and 8 weeks compared to the control group (P>0.05). The biomechanical properties at both nano and micro scales altered in different degrees between inner and outer layers in annulus fibrosus after immobilization for different times. Meanwhile, the fibril arrangement disorder and the upregulation of collagen II in annulus fibrosus were observed using hematoxylin/eosin staining and real-time RT-PCR, respectively. These results indicate that immobilization not only influenced the individual collagen fibril at the nano scale, but also suggested alterations of micro-biomechanics and cell response. This work provides a better understanding of IVD degeneration after immobilization and benefits to the clinical treatment related to disc immobilization

Introduction. The increase in revision joint replacement surgery and fractures of bone around orthopaedic implants may be partly addressed by keeping bone healthy around orthopaedic implants by inserting implants with mechanical properties closer to the patient's bone properties. We do not currently have an accurate way of calculating a patient's bone mechanical properties. We therefore posed a simple question: can data derived from a micro-indenter be used to calculate bone stiffness?. Methods. We received ethical approval to retrieve femoral heads and necks from patients undergoing hip replacement surgery for research. Cortical bone from the medial calcar region of the femoral neck was cut into 3×3×6mm cuboid specimens using a diamond wafering blade. Micro-indentation testing was performed in the direction of loading of the bone using a MicroMaterials (MicroMaterials, UK) indenter, using the high load micro-indentation stage (see Figure 1). To simulate in vivo testing, the samples were kept hydrated and were not fixed or polished. From the unloading curve after indentation, the elastic modulus was calculated, using the Oliver-Pharr method using the indentation machine software. To assess which microindentation machine settings most precisely calculate the elastic modulus we varied the loading and unloading rates, load and indenter tip shape (diamond Berkovich tip, 1mm diameter Zirconia spherical tip and 1.5mm diameter ruby spherical tip). Following this, for 11 patients' bone, we performed compression testing of the same samples after they were indented with the 1.5mm diameter ruby spherical tip to assess if there was a correlation between indentation values of apparent elastic modulus and apparent modulus values calculated by compression testing (see Figure 2). Platens compression testing was performed using an Instron 5565 (Instron, USA) materials testing machine. Bluehill compliance correction software (Instron, USA) was used to correct for machine compliance. The strain rate was set at 0.03mm/s. The apparent elastic modulus was calculated from the slope of the elastic region of the stress-strain graph. The correlation between values of apparent modulus from compression testing and indentation were analyzed using IBM SPSS Statistics 22. Results. The most precise results were obtained using a spherical indenter tip (1.5 mm diameter ruby ball), rather than a sharp Berkovich tip, high load (10N), a loading rate of 100 mN/s and unloading rate of 300 mN/s with a pause of 60 seconds at maximum load. We also used multiple load cycles with a peak load of 10N (see Figure 3). Using these optimal settings we calculated the mean elastic modulus over 10 cycles of testing with six indents on one sample to be 11.8 GPa (+/− 1.01). There was a moderate correlation between indentation and compression values of apparent modulus (r=0.62, n=11, p=0.04). Discussion. By using a spherical indenter tip and fast unloading it was possible to get precise apparent modulus values. The apparent modulus derived from micro-indentation, correlated moderately with that derived from direct compression testing. This early data suggests that microindentation may become a clinically relevant test of bone quality in real time

Sledging related minor and major injuries represent a significant workload at ski-area medical centers across the world. Although safety rules exist, they are seldom obeyed or enforced. We set out to determine the incidence of sledging related injuries, identifying trends and causative factors at a busy New Zealand Ski resort. All sledging related injuries presenting during a 70-day period were prospectively reviewed. Patient demographics, mechanism, diagnosis, and treatment were recorded. Sixty patients were identified, mean age 10 years, range 4-30 years. Injuries comprised; collisions with sledgers (21), collision with wall (14) and falling from sledge (14). Site of injury included head (36), lower limb (18), spine (9), upper limb (7), and abdomen (2). Fractures included; femur (1), tibia (1), fibula (1), ankle (2), cuboid (1), clavicle (2), scaphoid (1). One 9-year-old patient sustained a serious intracranial haemorrhage, with subsequent permanent neurological sequelae. Sledging related injuries are mostly minor, however significant major injuries do occur requiring intervention at a secondary center. The potential for serious morbidity is evident. Recommendations supporting safety improvement measures does exist, however most were not implemented by the study cohort examined. The use of basic cycling helmets would seem an appropriate minimum level of protection, and greater sledging safety awareness should be encouraged

Untill recently, major reduction defects of the tibia were treated by amputation and prosthetic fitting. However, Wada et al (1) and Weber (2) recently reported impressive results of limb reconstruction in children with tibial aplasia. If an attempt is being made to reconstruct the leg and foot, a clear understanding of the nature of anomalies is necessary. A retrospective study of case records and radiographs of children with congenital anomalies of the tibia seen at our centre was undertaken to determine the patterns of associated anomalies in the leg and foot. In addition, five amputated specimens of the leg and foot from children with complete tibial aplasia were dissected. A wide spectrum of congenital anomalies of the tibia was seen and this included complete aplasia, partial aplasia, hypoplasia, dyplastic trapezoidal tibia and congenital bowing. Complete and partial aplasia was seen either with or without duplication of the formed skeletal elements. The patterns of duplication that were seen included fibular dimelia, pre-axial mirror polydactyly, duplication of the calcaneum, cuboid and lateral cuneiforms. Trapezoidal dysplastic tibia was associated with duplication of the talus and pre-axial mirror polydactyly. Dissection of the amputated specimens of complete tibial aplasia revealed aplasia of some muscles, aberratant tendinous structures, abnormal insertion of muscles and absence of the plantar arterial arch. An understanding the nature of these associated anomalies in children with tibial aplasia and dyplasia will help the surgeon to decide the strategies for reconstruction of the limb if that is the desired option. At the other end of the spectrum of congenital anomalies of the tibia is posteromedial bowing which was considered an innocuous condition that required little or no treatment. A review of 20 cases of posteromedial bowing demonstrated that there are number of problems related to the leg, ankle and foot that may require surgical intervention

Objective. To assess the usefulness of radiographs alone to evaluate acute midfoot/forefoot injuries. We believe that foot injuries are often under-estimated and that CT scans should be routinely obtained to aid in their management and avoid additional morbidity for patients. Materials & Methods. In 26 months, 255 patients had foot injuries requiring X-Rays. Of these patients, 94 (37%) had primary radiographs indicating midfoot or forefoot fractures, and 28 had subsequent CT scans. Radiographs were retrospectively re-evaluated with respect to fracture location, type, mechanism of injury and then compared with CT results. Results. Of 255 patients, 213 (84%) had one or more fractures in their foot. A total of 397 fractures were seen with 105 patients having Os Calcis (41%) fractures. 94 patients (37%) had midfoot/forefoot fractures which included the 28 patients with subsequent CT scans. 56 patients (22%) had no injury. Of those patients with midfoot/forefoot injuries, 61 fractures were seen on plain radiographs and an additional 74 were identified on CT scanning. The major mechanism of injury in these patients was Road Traffic Accident (26 patients [28%]). Commonly missed individual fractures on plain radiography were Metatarsal (29), Cuboid (12) and Cuneiform fractures (11). Nine of the 29 (31%) metatarsal bone fractures involved missed fracture-dislocations of the Lisfranc joint. Other new fractures included Talus (4), Navicular (3), Os Calcis (2) and Tibia (2). 48 required operative fixation, including 20 patients that underwent CT scanning. We found that the sensitivity of radiographs in detection of midfoot fractures was low at 44%, and only 50% in forefoot injuries. Conclusion. In patients with high energy foot injury, and those with suspected complex injury, the sensitivity of radiography is only moderate at best. We suggest that CT scanning as the primary imaging modality would lead to a decrease in their morbidity