Human lower leg muscles grow asynchronously.

Muscle volume must increase substantially during childhood growth to generate the power required to propel the growing body. One unresolved but fundamental question about childhood muscle growth is whether muscles grow at equal rates; that is, if muscles grow in synchrony with each other. In this study, we used magnetic resonance imaging (MRI) and advances in artificial intelligence methods (deep learning) for medical image segmentation to investigate whether human lower leg muscles grow in synchrony. Muscle volumes were measured in 10 lower leg muscles in 208 typically developing children (eight infants aged less than 3 months and 200 children aged 5 to 15 years). We tested the hypothesis that human lower leg muscles grow synchronously by investigating whether the volume of individual lower leg muscles, expressed as a proportion of total lower leg muscle volume, remains constant with age. There were substantial age-related changes in the relative volume of most muscles in both boys and girls (p < 0.001). This was most evident between birth and five years of age but was still evident after five years. The medial gastrocnemius and soleus muscles, the largest muscles in infancy, grew faster than other muscles in the first five years. The findings demonstrate that muscles in the human lower leg grow asynchronously. This finding may assist early detection of atypical growth and allow targeted muscle-specific interventions to improve the quality of life, particularly for children with neuromotor conditions such as cerebral palsy.

Sex-Specific Association Patterns of Bone Microstructure and Lower Leg Arterial Calcification.

In conversations about bone loss and the importance of calcium homeostasis, patients frequently inquire about the association with arterial calcifications. Although a relationship between bone loss and the occurrence of vascular calcifications is suspected, it is not yet fully investigated and understood. This study aims to analyze associations between bone mineralization, structure, and vascular calcification at the lower leg in patients with low bone mineral density in HR-pQCT. We retrospectively analyzed 774 high-resolution quantitative computed tomography (HR-pQCT) scans of the distal tibia for the presence of vascular calcifications. After sex-specific propensity score matching for age and BMI to account for confounders, 132 patients remained for quantification of bone microstructure, bone density, lower leg arterial calcification (LLAC), and laboratory parameters of bone turnover. The interactions between bone parameters and vascular calcification were quantified by regression analyses. The calcium metabolism was not different between individuals with and without LLAC, nor oral calcium supplementation. Female patients with LLAC had a higher cortical perimeter (p = 0.016) compared to female patients without LLAC, whereas male patients with LLAC had lower cortical pore diameter than male patients without LLAC (p = 0.027). The appearance of LLAC was sex specifically associated with bone parameters. In female patients, only plaque density was associated with HR-pQCT bone parameters and age, whereas in male patients, plaque volume was associated with HR-pQCT parameters of the distal tibia. Female patients exhibit an increasing plaque density depended on age and trabecular thinning. Decreasing cortical pore diameter and trabecular number along with increasing bone mineralization are linked to increasing plaque volume in male patients.

Clinical outcomes of perforator-based propeller flaps versus free flaps in soft tissue reconstruction for lower leg and foot trauma: a retrospective single-centre comparative study.

BACKGROUND: The efficacy and safety of perforator-based propeller flaps (PPF) versus free flaps (FF) in traumatic lower leg and foot reconstructions are debated. PPFs are perceived as simpler due to advantages like avoiding microsurgery, but concerns about complications, such as flap congestion and necrosis, persist. This study aimed to compare outcomes of PPF and FF in trauma-related distal lower extremity soft tissue reconstruction. METHODS: We retrospectively studied 38 flaps in 33 patients who underwent lower leg and foot soft tissue reconstruction due to trauma at our hospital from 2015 until 2022. Flap-related outcomes and complications were compared between the PPF group (18 flaps in 15 patients) and the FF group (20 flaps in 18 patients). These included complete and partial flap necrosis, venous congestion, delayed osteomyelitis, and the coverage failure rate, defined as the need for secondary flaps due to flap necrosis. RESULTS: The coverage failure rate was 22% in the PPF group and 5% in the FF group, with complete necrosis observed in 11% of the PPF group and 5% of the FF group, and partial necrosis in 39% of the PPF group and 10% of the FF group, indicating no significant difference between the two groups. However, venous congestion was significantly higher in 72% of the PPF group compared to 10% of the FF group. Four PPFs and one FF required FF reconstruction due to implant/fracture exposure from necrosis. Additionally, four PPFs developed delayed osteomyelitis post-healing, requiring reconstruction using free vascularized bone graft in three out of four cases. CONCLUSIONS: Flap necrosis in traumatic lower-leg defects can lead to reconstructive failure, exposing implants or fractures and potentially causing catastrophic outcomes like osteomyelitis, jeopardizing limb salvage. Surgeons should be cautious about deeming PPFs as straightforward and microsurgery-free procedures, given the increased complication rates compared to FFs in traumatic reconstruction. DATA ACCESS STATEMENT: The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Outcomes comparison of elastic bandage versus lower-leg cast immobilization after anterior talofibular ligament repair.

PURPOSE: The aim of this study was to compare the clinical outcomes between patients with chronic ankle instability (CAI) undergoing arthroscopic anterior talofibular ligament (ATFL) repair who received elastic bandage treatment and those who received lower-leg cast immobilization. METHODS: CAI patients with isolated ATFL injury undergoing arthroscopic ATFL repair from January 2017 and August 2019 were included in the study. The visual analogue scale (VAS) at rest and during activities, American Orthopedic Foot and Ankle Society (AOFAS) score, Karlsson Ankle Functional Score (Karlsson score), and time of returning to walk, walk normally, work and sports were evaluated preoperatively, and at 6 months and 12 months follow-up. RESULTS: A total of 41 patients were included in this study. Among them, 24 patients accepted lower-leg cast fixation, and the other 17 patients were immobilized with elastic bandage. Compared to patients with lower-leg immobilization, patients with elastic bandage fixation had significantly lower VAS during activities (P = 0.021) and higher AOFAS score (P = 0.015) at 12 months follow-up. The Karlsson score at 6 months follow-up were significantly higher in elastic bandage group than those in lower-leg group (P = 0.011). However, no significant difference was observed in time of returning to walk, work and sports between the two groups. CONCLUSION: Elastic bandage treatment was better than lower-leg cast immobilization in terms of eliminating pain symptom at 12 months follow-up, and improving ankle functional outcome at 6 months follow-up. Moreover, the present study emphasized that lower-leg cast immobilization offered no advantages in arthroscopic ATFL repair postoperative immobilization. STUDY DESIGN: Cohort study; Level of evidence, 3.

Accuracy of a portable lower-limb muscle strength measuring device with a training function.

[Purpose] Quadriceps muscle strength is essential for daily living activities. Therefore, we developed a compact and simple lower limb muscle strength measuring device (LocomoScan [LCS]). This study aimed to compare LCS with other instruments to analyze its simplicity, reproducibility, and accuracy. [Participants and Methods] One hundred and four healthy university students (56 males and 48 females) were included in the study. The knee extension force was measured using LCS, and the knee extension torque was measured using other devices (Cybex). In addition, lower leg muscle mass was measured using a body composition meter. The reproducibility of LCS and the correlation between the knee extension torque and lower leg muscle mass were evaluated. [Results] The measurement reproducibility of LCS was significantly higher. The knee extension force confirmed the proportional relative reliability of Cybex with knee extension torque. A relationship between knee extension force and lower limb muscle mass was also observed, indicating that muscle mass cannot be estimated as muscle strength. [Conclusion] The high reproducibility of the knee extension force measurement using LCS demonstrates its potential as a portable alternative instrument for muscle strength measurement in clinical practice. Therefore, LCS device is a simple and effective tool for assessing muscle strength.

Ulcerated skin evaluation by electrical impedance measurements.

In the presented study, the transdermal results from the areas surrounding the ulcerated skin areas were compared with those obtained from healthy skin tissue. The analysis of electrical parameters, such as the slope of the Nyquist plot, min. IM, min. RE, min. f, Imagine part index, Phase index, Real part index, and Magnitude index were conducted. Electrical parameters have been measured in the group without lower leg ulceration and in the group with lower leg ulcers. On the basis of the statistical analysis, it was determined that these parameters may be effective in the evaluation of the skin. In fact, the skin surrounding the ulceration was characterised by different values of electrical parameters as compared with healthy skin tissue. A statistically significant difference was found in the electrical parameters obtained for the healthy leg skin and the skin surrounding the ulceration. This study was to investigate the applicability of electrical parameters in the evaluation of the skin in lower leg ulcers. The electrical parameters can be used as an effective tool in assessing the condition of the skin, both healthy and surrounding the ulcerations. The most useful parameters in assessing skin condition using electrical parameters include min. IM, min. RE, min. f, Imagine part index, Phase index, and Magnitude index.

31 P MRSI at 7 T enables high-resolution volumetric mapping of the intracellular magnesium ion content in human lower leg muscles.

PURPOSE: The non-invasive determination of the free magnesium ion concentration ([Mg2+free ]) using 31 P MRSI in vivo is of interest in research on various pathologies, e.g. diabetes. The purpose of this study was to demonstrate the potential of 31 P MRSI at 7 T to enable volumetric, high-resolution mapping of [Mg2+free ]. METHODS: 3D 31 P MRSI datasets from the lower leg of three healthy volunteers were acquired at B0  = 7 T with a nominal spatial resolution of (8 × 8 × 16) mm3 in 56 min. Volumetric [Mg2+free ] maps were calculated based on the quantified local chemical shift difference between the α- and ß-resonance of adenosine triphosphate (ATP) considering also local pH values. Mean [Mg2+free ] values from three different muscle groups were compared. To demonstrate the potential of reducing the measurement time, the analysis was repeated on the acquired MRSI data retrospectively reconstructed with fewer averages. RESULTS: The generated [Mg2+free ] maps revealed local differences, and mean [Mg2+free ] values of (1.08 ± 0.03) mM were found in the tibialis anterior, (0.91 ± 0.04) mM in the soleus and (0.98 ± 0.03) mM in the gastrocnemius medialis. The time-reduced 28-min scan resulted in comparable [Mg2+free ] maps, and mean values being in agreement with the values from the 56-min scan. CONCLUSION: 31 P MRSI at 7 T enables volumetric, high-resolution mapping of free magnesium ion content in human lower leg muscles. The measurement time of the 31 P MRSI acquisition can be reduced to 28 min, opening the potential to apply volumetric [Mg2+free ] mapping for the investigation of pathologies with altered magnesium homeostasis.

Effect of 6-month high-impact step aerobics and resistance training on BMD and tibial bending strength in sedentary premenopausal women.

The rationale of this study was to examine the effectiveness of 6-month high-impact step aerobics (SA) or moderate-intensity resistance training exercise (RT) on bone mineral density (BMD) and bone bending strength in sedentary women. Results show that SA enhanced BMD in the heel, lower leg, and lumbar spine 2. INTRODUCTION: To determine the effectiveness of 6 months of high-impact step aerobics (SA) or moderate-intensity resistance training (RT) on areal bone mineral density (aBMD) and tibial bending strength in sedentary premenopausal women. METHODS: Sixty-nine women (20-35 years old) who were randomly assigned to RT (n = 22), SA (n = 26), or non-treatment control (CON, n = 21) groups completed the study. SA had a minimum of 50 high-impact landings each training session. RT had a periodized lower body resistance training program incorporating eight exercises (65-85% of 1 repetition maximum: 1-RM). Both RT and SA met 3 times weekly. aBMD was assessed using dual X-ray absorptiometry (DXA). Tibial bending strength was assessed using mechanical response tissue analysis (MRTA). Measurements at 6 months were compared to baseline using ANCOVA, adjusted for baseline measures and covariates with α = 0.05. RESULTS: Calcaneus aBMD (0.0176 vs -0.0019 or -0.0009 g/cm2 relative to RT, p < 0.004, and CON, p < 0.006, respectively), lower leg aBMD (0.0105 vs -0.0036 g/cm2, relative to RT, p = 0.02), and lumbar spine 2 (L2) aBMD (0.0082 vs -0.0157 g/cm2 relative to CON, p < 0.02) were significantly greater in the SA group after 6 months. Tibial bending strength and bone resorption biomarkers were unchanged in all three groups after 6 months. CONCLUSION: Sedentary premenopausal women engaging in 6 months of high-impact aerobic exercise improved aBMD in the calcaneus, lower leg, and L2.

Vibrio vulnificus necrotizing fasciitis with sepsis presenting with pain in the lower legs in winter: a case report.

BACKGROUND: Vibrio vulnificus infections develop rapidly and are associated with a high mortality rate. The rates of diagnosis and treatment are directly associated with mortality. CASE PRESENTATION: We describe an unusual case of a 61-year-old male patient with chronic liver disease and diabetes who presented with a chief complaint of pain in both lower legs due to V. vulnificus infection in winter. Within 12 h of arrival, typical skin lesions appeared, and the patient rapidly developed primary sepsis. Despite prompt appropriate antibiotic and surgical treatment, the patient died 16 days after admission. CONCLUSION: Our case findings suggest that V. vulnificus infection should be suspected in patients with an unclear infection status experiencing pain of unknown origin in the lower legs, particularly in patients with liver disease or diabetes, immunocompromised status, and alcoholism.

Lower leg symmetry: a Q3D-CT analysis.

PURPOSE: In fracture and realignment surgery, the contralateral unaffected side is often used as a model or template for the injured bone even though clinically valuable quantitative data of bilateral symmetry are often unavailable. Therefore, the objective of the present study was to quantify and present the bilateral symmetry of the tibia and fibula. METHODS: Twenty bilateral lower-leg CT scans were acquired in healthy volunteers. The left and right tibia and fibula were segmented resulting in three-dimensional polygons for geometrical analyses (volume, surface and length). The distal and proximal segment of the right tibia of each individual was subsequently matched to the left tibia to quantify alignment differences (translation and rotation). Bone symmetry on group level was assessed using the Student's t test and intra-individual differences were assessed using mixed-models analyses. RESULTS: Intra-individuals differences were found for tibia volume (5.2 ± 3.3 cm3), tibia surface (5.2 ± 3.3 cm2), translations in the lateral (X-axis; 9.3 ± 8.9 mm) and anterior direction (Y-axis; 7.1 ± 7.0 mm), for tibia length (translation along Z-axis: 3.1 ± 2.4 mm), varus/valgus (φz: 1.7o ± 1.4°), and endotorsion/exotorsion (φz: 4.0o ± 2.7°). CONCLUSION: This study shows intra-individual tibia asymmetry in both geometric and alignment parameters of which the surgeon needs to be aware in pre-operative planning. The high correlation between tibia and fibula length allows the ipsilateral fibula to aid in estimating the original tibia length post-injury. Future studies need to establish whether the found asymmetry is clinically relevant when the contralateral side is used as reference in corrective surgery. LEVEL OF EVIDENCE: III cohort study.

[Cerebral fat embolism syndrome after polytrauma : Complication after fracture treatment of several long bones of the lower extremities]. / Zerebrales Fettemboliesyndrom nach Polytrauma : Komplikation bei Frakturversorgung mehrerer langer Röhrenknochen der unteren Extremität.

In consequence of a car accident a 20-year-old woman with bilateral fractures of the femur and an unilateral lower leg fracture was treated with external fixation. Afterwards she was soporific with signs of impaired consciousness and required intubation and intensive medical care surveillance. A cerebral fat embolism syndrome could be detected as the reason, which was characterized by acute respiratory insufficiency, neurological symptoms and petechiae. Subsequently, definitive treatment was performed by intramedullary nailing. After neurological and orthopedic rehabilitation no performance inhibiting limitations remained.

LONG-TERM RESULTS OF TREATING PATIENTS WITH OPEN FRACTURES OF LOW-LEG BONES.

OBJECTIVE: The aim: To analyse long-term results of treating patients with open fractures of low-leg bones within a specific time period and to describe concomitant problems. PATIENTS AND METHODS: Materials and methods: A retrospective study was carried out to evaluate the results of the final treatment of patients after one year and after five years. Patients were divided into two groups. Group I included 47 (61.84%) patients for whom the treatment method was changed from external fixation to internal fixation. Group II included 29 (38.16%) patients for whom the final treatment of an open fracture was performed with an external fixation device without changing the method. The study exclusion criteria were patients under 18 years old and patients with gunshot fractures of the lower leg bones. RESULTS: Results: Patient treatment included initial surgical debridement and fracture stabilization with external fixation devices. In all patients, wound healing occurred within 30 days (on average, 24 ± 4.5 days). When evaluating the treatment of patients in group I, 32 (68.09%) of them underwent a one-stage removal of an external fixation device and osteosynthesis of fragments during the first 7-10 days. In 3 (20.0%) patients, osteosynthesis was performed with an intramedullary locking nail, in 12 (80.0%) patients - with a plate. The decision to change the fixation method was made taking into account clinical and laboratory parameters. It is noted that the treatment of patients with type III open fractures of the lower leg bones according to the Gustilo-Andersen classification, provided that the method of external fixation is replaced with an internal one, gives better results compared to osteosynthesis with external fixation devices. CONCLUSION: Conclusions: Treatment of patients with high-energy injuries of the lower leg bones is a long-term process. It is possible to improve the therapy efficiency by changing the fixation method from external to internal one. In this regard, the main evaluative characteristics are such indicators as uncomplicated wound healing combined with the absence of laboratory and clinical signs of inflammation.

Three-dimensional motion analysis of the hindfoot resulting from simulated contraction of individual lower leg muscles utilizing Thiel-embalmed cadavers.

BACKGROUND: Joint movement within the foot is complex involving multiple muscles. We evaluated three-dimensional movement of the hindfoot through simulated traction of extrinsic tendons of the foot. METHODS: Six Thiel-embalmed cadavers were utilized and thread was sutured to each tendon of the lower leg muscles. Traction of the thread was prescribed and the change of calcaneal position used to quantify foot motion was measured for each increment using a magnetic tracking system. RESULTS: As the tendon traction length advanced, the angle of the calcaneus with respect to the tibia increased linearly. Eversion and abduction angles due to extensor digitorum longus (EDL) traction were significantly greater than that due to the peroneus longus. Plantarflexion due to Achilles tendon traction was significantly greater than that of other plantarflexors. CONCLUSIONS: Our results demonstrated three-dimensional characteristics of hindfoot motion by simulated muscle contraction and importance of EDL as an evertor. These information should be applicable for tendon transfer procedures around the ankle and physical therapy for ankle dysfunction such as chronic ankle instability.

Reliability of lower leg muscle thickness measurement along the long axis of the muscle using ultrasound imaging, in a sitting position.

[Purpose] To verify the reliability and validity of lower leg muscle thickness (MT) assessment along the muscle's long axis using ultrasound imaging (USI) in a sitting position. [Participants and Methods] Twenty healthy adult female participants (aged, 20.3 ± 0.9 years) were included in the study. Intra- and inter-examiner reliability of the proximal, middle, and distal MT of the tibialis anterior (TA) and medial head of the gastrocnemius (GM) were verified using USI in a sitting position. Additionally, the relationship between MT measurement using USI and muscle cross-sectional area (MCSA) measurement using magnetic resonance imaging (MRI), as well as the ankle joint's maximum muscle strength, were examined. [Results] The reliability of TA and GM MT measurement using USI was high for all regions. The relationship between MCSA measurement using MRI and MT measurement using USI showed a significant correlation in all the regions for both muscles. The relationship between ankle muscle strength and USI of MT was not significantly correlated in any region for both muscles. [Conclusion] Measurement of MT using USI is reliable and valid for MCSA, but must be combined with assessments of other factors for muscle strength.

[Endovascular interventions in patients with glass iii infrainguinal arterial disease: 2-year results]. / Endovaskulyarnye interventsii u patsientov s infraingvinal'nymi porazheniyami GLASS III stepeni: rezul'taty dvukhletnego nablyudeniya.

OBJECTIVE: To evaluate the results of endovascular surgery in patients with chronic limb-threatening ischemia (CLTI) with infrainguinal arterial disease GLASS III. MATERIAL AND METHODS: Treatment outcomes were analyzed for the period 2017-2018. Inclusion criteria were age over 18 years, CLTI, extended (>20 cm) stenosis de novo and occlusion of femoropopliteal segment (FPS) combined with occlusive lesion of tibial arteries. We analyzed 147 patients divided into 2 groups depending on stenting strategy. FPS-1-TA included 53 patients who underwent angioplasty (± stenting) of femoropopliteal arteries and lower leg arteries resulted at least one patent tibial artery. FPS-2-TA enrolled 94 patients who underwent angioplasty of femoropopliteal arteries and lower leg arteries resulted ≥2 patent tibial arteries. Mean age was 71.0±9.8 years. There were 75 men. Demographics and clinical characteristics of patients were similar. RESULTS: Technical success rate was 100%. Mean length of stenting was 203 ± 99 mm. Occlusion of all 3 leg arteries correlated with high incidence of femoropopliteal stenting. In the FPS-1-TA group, stents were implanted in 39 patients, in the FPS-2-TA group - in 71 patients (73.6% and 75.5%, respectively, p=0.8). Braided nitinol stents were used for stenting of the lower third of superficial femoral artery and p1-p3 segments. Mean follow-up period was 22.6±1.1 months. Two-year results were not age-specific in our study. Kaplan-Meier overall survival, freedom from amputation and amputation-free survival for the entire sample were 79.6%, 81.0%, and 66.7%, respectively. We compared these values in both groups using Mantel-Cox log-rank test and obtained significant differences (67.9% vs 86.2%, p=0.004; 64.2% vs 90%, p<0.0001; 47.2% vs 77.7%, p<0.0001, respectively). CONCLUSION: Our results are comparable with literature data regarding freedom from amputation and amputation-free survival. We obtained significant differences in overall survival and freedom from amputation depending on endovascular strategy for tibial arteries. Correction of distal vessels with recanalization of at least two tibial arteries is advisable for endovascular treatment of diffuse complex lesions.

Simultaneous T1 , T2 , and T1ρ relaxation mapping of the lower leg muscle with MR fingerprinting.

PURPOSE: To develop a novel MR-fingerprinting (MRF) pulse sequence that is insensitive to B1+ and B0 imperfections for simultaneous T1 , T2 , and T1ρ relaxation mapping. METHODS: We implemented a totally balanced spin-lock (TB-SL) module to encode T1ρ relaxation into an existing MRF framework that encoded T1 and T2 . The spin-lock module used two 180° pulses with compensatory phases to reduce T1ρ sensitivity to B1 and B0 inhomogeneities. We compared T1ρ measured using TB-SL MRF in Bloch simulations, model agar phantoms, and in vivo experiments to those with a self-compensated spin-lock preparation module (SC-SL). The TB-SL MRF repeatability was evaluated in maps acquired in the lower leg skeletal muscle of 12 diabetic peripheral neuropathy patients, scanned two times each during visits separated by about 30 days. RESULTS: The phantom relaxation times measured with TB-SL and SC-SL MRF were in good agreement with reference values in regions with low B1 inhomogeneities. Compared with SC-SL, TB-SL MRF showed in experiments greater robustness against severe B1 inhomogeneities and in Bloch simulations greater robustness against B1 and B0 . We measured with TB-SL MRF an average T1 = 950.1 ± 28.7 ms, T2 = 26.0 ± 1.2 ms, and T1ρ = 31.7 ± 3.2 ms in skeletal muscle across patients. Bland-Altman analysis demonstrated low bias between TB-SL and SC-SL MRF and between TB-SL MRF maps acquired in two visits. The coefficient of variation was less than 3% for all measurements. CONCLUSION: The proposed TB-SL MRF sequence is fast and insensitive to B1+ and B0 imperfections. It can simultaneously map T1 , T2 , T1ρ , and B1+ in a single scan and can potentially be used to study muscle composition.

Deep learning methods for automatic segmentation of lower leg muscles and bones from MRI scans of children with and without cerebral palsy.

Cerebral palsy is a neurological condition that is known to affect muscle growth. Detailed investigations of muscle growth require segmentation of muscles from MRI scans, which is typically done manually. In this study, we evaluated the performance of 2D, 3D, and hybrid deep learning models for automatic segmentation of 11 lower leg muscles and two bones from MRI scans of children with and without cerebral palsy. All six models were trained and evaluated on manually segmented T1 -weighted MRI scans of the lower legs of 20 children, six of whom had cerebral palsy. The segmentation results were assessed using the median Dice similarity coefficient (DSC), average symmetric surface distance (ASSD), and volume error (VError) of all 13 labels of every scan. The best performance was achieved by H-DenseUNet, a hybrid model (DSC 0.90, ASSD 0.5 mm, and VError 2.6 cm3 ). The performance was equivalent to the inter-rater performance of manual segmentation (DSC 0.89, ASSD 0.6 mm, and VError 3.3 cm3 ). Models trained with the Dice loss function outperformed models trained with the cross-entropy loss function. Near-optimal performance could be attained using only 11 scans for training. Segmentation performance was similar for scans of typically developing children (DSC 0.90, ASSD 0.5 mm, and VError 2.8 cm3 ) and children with cerebral palsy (DSC 0.85, ASSD 0.6 mm, and VError 2.4 cm3 ). These findings demonstrate the feasibility of fully automatic segmentation of individual muscles and bones from MRI scans of children with and without cerebral palsy.

Peripheral quantitative computed tomography of the lower leg in children and adolescents: bone densities, cross-sectional sizes and muscle distribution reference data.

OBJECTIVES: Peripheral quantitative computed tomography is utilised in increasing numbers of paediatric studies, however, very little is known about the reference limits for pQCT tibia measurements. The purpose of this study was to establish country-specific reference data for bone densities, cross-sectional sizes, strength and regional muscle distribution measured by pQCT in children and adolescents. METHODS: Stratec XCT 2000L apparatus was used. The measurement sites were 4%, 14%, 38% and 66% of the tibia length. The study group consisted of 222 participants (103 girls) aged 4,3-19,4 yrs. ANCOVA was used to assess the main determinants of pQCT outcomes. The LMS method was used to fit the percentile curves for each outcomes. RESULTS: Weight and age were the main determinants for most of the pQCT outcomes. Smoothed percentile curves were developed by age and by height for both sexes. CONCLUSION: In this study we present reference data for bone densities, cross-sectional size and strength as well as for regional muscle distribution measured by pQCT at certain sites of the lower leg to allow simple calculation of reliable Z scores.

Hip Joint Contact Loading and Muscle Forces During Running With a Transtibial Amputation.

People with unilateral transtibial amputations (TTA) have greater risks of bilateral hip osteoarthritis, related to asymmetric biomechanics compared to people without TTA. Running is beneficial for physical health and is gaining popularity. However, people with TTA may not have access to running-specific prostheses (RSPs), which are designed for running, and may instead run using their daily-use prosthesis (DUP). Differences in joint loading may result from prosthesis choice; thus, it is important to characterize changes in peak and impulsive hip joint contact loading during running. Six people with and without TTA ran at 3.5 m/s while ground reaction forces, kinematics, and electromyography were collected. People with TTA ran using their own RSP and DUP. Musculoskeletal models incorporating prosthesis type of each individual were used to quantify individual muscle forces and hip joint contact forces (HJCFs) during running. People using RSPs had smaller bilateral peak hip joint contact forces compared to when wearing DUPs during stance and swing, and a smaller impulse over the entire gait cycle. Greater amputated leg peak hip joint contact forces for people wearing DUPs compared to RSPs occurred with greater forces from the ipsilateral gluteus maximus during stance. People with TTA also had greater bilateral peak hip joint contact forces during swing compared to people without TTA, which occurred with greater peak gluteus medius forces. Running with more compliant RSPs may be beneficial for long-term joint health by reducing peak and impulsive hip loading compared to DUPs.

Debriding effect of amino acid-buffered hypochlorite on hard-to-heal wounds covered by devitalised tissue: pilot study.

OBJECTIVE: Wounds such as lower extremity ulcers are serious, costly and frequently hard to heal. Guidelines conclude that new dressings and treatments generally fail to show superiority compared with standard of care. Several mechanisms are probably responsible for impaired healing of hard-to-heal wounds, including inflammation and infection. Amino acid-buffered hypochlorite has presumed antiseptic and antibacterial properties and has been shown to be useful in the treatment of diabetic foot ulcers (DFUs). We evaluated the debriding effect of amino acid-buffered hypochlorite (ChloraSolv) on full skin hard-to-heal lower extremity ulcers covered with devitalised tissue (≥50%), with six applications over 5 weeks and follow-up at 12 weeks. METHOD: This was an open-label, single-arm, multicentre, pre-market pilot investigation. We recruited subjects with a lower extremity ulcer, covered with devitalised tissue (≥50%), who were candidates for cleansing and debridement/desloughing. There was a weekly application of the investigational device for five weeks. Follow-up for wound status evaluation was performed at 12 weeks from baseline. RESULTS: We evaluated 57 subjects (33 males, 24 females, median age 73 years, range 51-90 years) (intention-to-treat). Of these, 61.4% had a leg ulcer and 38.6% a foot ulcer. The median wound size at baseline was 7.7cm2 (range 2.1-52cm2) with devitalised tissue coverage of 76.5%. After 5 weeks, a decrease of 72.7% in devitalised tissue was seen, and 71.4% of the subjects showed a decrease in devitalised tissue of ≥50% (evaluated independently using PictZar). At 12 weeks' follow-up the decrease in devitalised tissue was 84.4%. Wound-related pain was reported by ten subjects, resulting in 17 adverse events (AEs). Among these, 12 AEs from eight subjects were recorded as possibly or probably related to the investigational device and one AE was reported to have a causal relationship with the investigational device. CONCLUSION: This clinical study suggests that amino acid-buffered hypochlorite can be effective and well tolerated in the treatment of hard-to-heal lower extremity ulcers to dissolve and remove devitalised tissue.