Summary

For injuries to the lower leg or forearm, supplemental support from soft tissue compression (STC) with a splint or brace-like system and combined with external fixation could be done effectively and quickly with a minimal of facilities in the field.

Primary malignant bone and soft tissue tumours often occur in the lower extremities of active individuals including children, teenagers and young adults. Survivors routinely face long-term physical disability. Participation in sports is particularly important for active young people but the impact of sarcoma treatment is not widely recognised and clinicians may be unable to provide objective advice about returning to sports. We aimed to identify and summarise the current evidence for involvement in sports following treatment of lower limb primary malignant bone and soft tissue tumours. A comprehensive search strategy was used to identify relevant studies combining the main concepts of interest: (1) Bone/Soft Tissue Tumour, (2) Lower Limb, (3) Surgical Interventions and (4) Sports. Studies were selected according to eligibility criteria with the consensus of three authors. Customised data extraction and quality assessment tools were used. 22 studies were selected, published between 1985 – 2020, and comprising 1005 patients. Fifteen studies with data on return to sports including 705 participants of which 412 (58.4%) returned to some form of sport at a mean follow-up period of 7.6 years. Four studies directly compared limb sparing and amputation; none of these were able to identify a difference in sports participation or ability. Return to sports is important for patients treated for musculoskeletal tumours, however, there is insufficient published research to provide good information and support for patients. Future prospective studies are needed to collect better pre and post-treatment data at multiple time intervals and validated clinical and patient sports participation outcomes such as type of sports participation, level and frequency and a validated sports specific outcome score, such as UCLA assessment. In particular, more comparison between limb sparing and amputation would be welcome

Purpose. Extraskeletal chondrosarcoma is a rare tumor with an indolent course and high propensity for local recurrence and metastasis. This tumor most commonly presents in the proximal extremities of middle-aged males, and is commonly asymptomatic. Although slow growing, these tumors have a significant risk of eventual relapse and metastases, especially to the lung. There are no clinical trials that investigated the best treatment options for this tumor given its very low incidence. The aim of this study is to present the surgical and clinical results of extraskeletal chondrosarcoma, which is a rare tumor. Methods. In our clinic, the information of 13 patients who were diagnosed with extra-skeletal chondrosarcoma between 2006 and 2018 were retrospectively reviewed. Demographic information, tumor size, surgical treatments, chemotherapy and radiotherapy status, follow-up times, recurrence and metastases of the patients were recorded. Results. This study included 13 patients with an average age of 53.6 ± 15 (range, 28 to 73) years diagnosed with extraskelatal chondrosarcoma. In 8 of the patients, the tumor was located in the lower limbs and it was observed that the thigh was located mostly (46.2%). The mean follow-up period of the patients was 52.8 ± 19.9 (range, 24 to 96) months. All patients underwent extensive resection and only one patient had a positive surgical margin. In the follow-up, 5 (38.5%) of the patients developed recurrence, while 6 patients had lung metastasis (46.2%) and 53.8% (7 patients) of the patients exitus. The mean tumor size was 10.4 ± 3.2 (range, 5 to 17) cm. The median survival time of the patients in the study was 61 (50.5–71.4) months. The 5-year survival rate is 51.8%. There was no significant difference between survival times according to age, gender, side, limb location, postoperative RT, recurrence and presence of lung metastasis (log rank tests p > 0.05). The cut off value for exitus obtained by ROC analysis of tumor size was determined as 11 cm (fig 1). Accordingly, the survival time of patients with 11 cm and above tumor size was observed to be statistically significantly shorter. Conclusion. Consequently, ECM is a rare soft tissue sarcoma with high local recurrence and metastasis capacity. Therefore, close follow-up is recommended. The first option should be extensive resection. Studies with large patient series on the prognostic factors of the future ECM are needed. For any figures or tables, please contact the authors directly

Differences at motor control strategies to provide dynamic balance in various tasks in diabetic polyneuropatic (DPN) patients due to losing the lower extremity somatosensory information were reported in the literature. It has been stated that dynamics of center of mass (CoM) is controlled by center of pressure (CoP) during human upright standing and active daily movements. Indeed analyzing kinematic trajectories of joints unveil motor control strategies stabilizing CoM. Nevertheless, we hypothesized that imbalance disorders/CoM destabilization observed at DPN patients due to lack of tactile information about the base of support cannot be explained only by looking at joint kinematics, rather functional foot usage is proposed to be an important counterpart at controlling CoM. In this study, we included 14 DPN patients, who are diagnosed through clinical examination and electroneuromyography, and age matched 14 healthy subjects (HS) to identify control strategies in functional reach test (FRT). After measuring participants’ foot arch index (FAI) by a custom-made archmeter, they were tested by using a force plate, motion analysis system, surface electromyography and pressure pad, all working in synchronous during FRT. We analyzed data to determine effect of structural and functional foot pathologies due to neuropathy on patient performance and postural control estimating FAI, reach length (FR), FR to height (H) ratio (FR/H; normalized FR with respect to height), displacement of CoM and CoP in anteroposterior direction only, moment arm (MA, defined as the difference between CoP and CoM at the end of FRT), ankle, knee and hip joint angles computed at the sagittal plane for both extremities. Kinematic metrics included initial and final joint angles, defined with respect to start and end of reaching respectively. Further difference in the final and initial joint angles was defined as Δ. FAI was founded significantly lower in DPN patients (DPN: 0.3404; HS: 0.3643, p= <0.05). The patients’ FR, FR/H and absolute MA and displacement of CoM were significantly shorter than the control group (p= <0.05). Displacement of CoP between the two groups were not significant. Further we observed that CoM was lacking CoP in DPN patients (mean MA: +0.88 cm), while leading CoP in HS (mean MA: −1.59 cm) at the end of FRT. All initial angles were similar in two groups, however in DPN patients final right and left hip flexion angle (p=0.016 and p=0.028 respectively) and left ankle plantar flexion angle (p=0.04) were smaller than HS significantly. DPN patients had significantly less (p=0.029) hip flexion (mean at right hip angle, Δ=25.0°) compared to HS (Δ=33.53°) and ankle plantar flexion (DPN mean at right ankle angle, Δ=6.42°, HS mean Δ=9.07°; p=0.05). The results suggest that movement of both hip and ankle joints was limited simultaneously in DPN patients causing lack of CoM with respect to CoP at the end of reaching with significantly lower FAI. These results lead to the fact that cutaneous and joint somatosensory information from foot and ankle along with the structure of foot arch may play an important role in maintaining dynamic balance and performance of environmental context. In further studies, we expect to show that difference at control strategies in DPN patients due to restricted functional foot usage might be a good predictor of how neuropathy evolves to change biomechanical aspects of biped erect posture

Autologous bone grafting is a standard procedure for the clinical repair of skeletal defects, and good results have been obtained. Autologous vascularized bone grafting is currently the procedure of choice because of high osteogenic potential and resistance against reabsorption. Disadvantages of this procedure include limited availability of donor sites, clinical difficulty in handling, and a failure rate exceeding 10%. Allografts are often used for massive bone loss, but since only the marginal portion is newly vascularized after the implantation non healing fractures are often reported, along with a graft reabsorption. To overcome these problems, some studies in literature tried to conjugate bone graft and vascular supply, with encouraging results. On the other side, several studies in literature reported the ability of bone marrow derived cells to promote neo-vascularization. In fact, bone marrow contains not only hematopoietic stem cells (HSCs) and MSCs as a source for regenerating tissues but also accessory cells that support angiogenesis and vasculogenesis by producing several growth factors. In this scenario a new procedure was developed, consisting in an allogenic bone graft transplantation in a critical size defect in rabbit radius, plus a deviation at its inside of the median artery and vein with a supplement of autologous bone marrow concentrate on a collagen scaffold. Twenty-four New Zealand male white rabbits (2500–3000 g) were divided into 2 groups, each consisting of 12 animals. Surgeries were performed as follow:. −. Group 1 (#12): allogenic bone graft (left radius) / allogenic bone graft + vascular pedicle + autologous bone marrow concentrate (right radius). −. Group 2 (#12): sham operated (left radius)/ allogenic bone graft + vascular pedicle (right radius). For each group, 3 experimental time: 8, 4 and 2 weeks (4 animals for each time). The bone used as graft was previously collected from an uncorrelated study. An in vitro evaluation of bone marrow concentrate was performed in all cases, and at the time of sacrifice histological and histomorphometrical assessment were performed with immunohistochemical assays for VEGF, CD31 e CD146 to highlight the presence of vessels and endothelial cells. Micro-CT Analysis with quantitative bone evaluation was performed in all cases. The bone marrow concentrate showed a marked capability to differentiate into osteogenic, chondrogenic and agipogenic lineages. No complications such as infection or intolerance to the procedure were reported. The bone grafts showed only a partial integration, mainly at the extremities in the group with vascular and bone marrow concentrate supplement, with a good and healthy residual bone. immunohistochemistry showed an interesting higher VEGF expression in the same group. Micro CT analysis showed a higher remodeling activities in the groups treated with vascular supplement, with an area of integration at the extremities increasing with the extension of the sacrifice time. The present study suggests that the vascular and marrow cells supplement may positively influence the neoangiogenesis and the neovascularization of the homologous bone graft. A longer time of follow up and improvement of the surgical technique are required to validate the procedure

Summary. These data suggest that PTH treatment for stimulation of bone healing after trauma is not much dependent on mechanical stimulation and therefore, roughly equal treatment effects might be expected in the upper and lower extremities in humans. Introduction. Stimulation of bone formation by PTH is known to, in part, act via increased mechanosensitivity. Therefore, unloading should decrease the response to PTH treatment in uninjured bone. This has served as a background for speculations that PTH might be less efficacious for human fracture treatment in unloaded limbs, e.g. for distal radial fractures. We analyzed if the connection with mechanical stimulation also pertains to bone formation after trauma in cancellous bone. Methods. 20 male SD rats, 8 weeks old, had one hind leg immobilised via Botox injections. At 10 weeks of age the rats received bilateral screw implants into their proximal tibiae. Half of the rats were given daily injections of 5µg/kg PTH(1–34). After two weeks of healing, the tibias and femurs were harvested. Mechanical testing of screw fixation (pull-out) and µCT of the cancellous bone of the distal femurs was performed. Results. The pull-out forces served as a read-out for cancellous bone formation after trauma. PTH more than doubled the pull-out force in the unloaded limbs (from 14 to 30 N), but increased it by less than half in the loaded (from 30 to 44 N). These force values are not limited by a ceiling effect, and the difference in relative effect of PTH was significant (p = 0.03). Discussion/Conclusion. PTH appeared to exert a greater effect on bone healing in the unloaded limbs, compensating for the lack of mechanical stimulation. These data suggest that PTH treatment for stimulation of bone healing after trauma is not much dependent on mechanical stimulation. Therefore, roughly equal treatment effects might be expected in the upper and lower extremities in humans

Objectives. The clinical utility of routine cross sectional imaging of the abdomen and pelvis in the screening and surveillance of patients with primary soft-tissue sarcoma of the extremities for metastatic disease is controversial, based on its questionable yield paired with concerns regarding the risks of radiation exposure, cost, and morbidity resulting from false positive findings. Methods. Through retrospective review of 140 patients of all ages (mean 53 years; 2 to 88) diagnosed with soft-tissue sarcoma of the extremity with a mean follow-up of 33 months (0 to 291), we sought to determine the overall incidence of isolated abdominopelvic metastases, their temporal relationship to chest involvement, the rate of false positives, and to identify disparate rates of metastases based on sarcoma subtype. Results. A total of four patients (2.9%) exhibited isolated abdominopelvic metastatic disease during the surveillance period. In all cases of concomitant chest and abdominopelvic disease, chest involvement preceded abominopelvic involvement. There was a significant false positive rate requiring invasive workup. Conclusions. In the setting of a relative paucity of evidence concerning a rare disease process and in difference to recently published investigations, we add a clinical cohort not supportive of routine cross sectional imaging of the abdomen and pelvis. Cite this article: Bone Joint Res 2015;4:45–9

Background. The traditional Kocher approach for lateral elbow exposure is often complicated by injury to the posterior interosseous nerve (PIN) and the lateral ulnar collateral ligamentous (LUCL). Kaplan approach is less commonly used, due to its known proximity to the PIN. Extensor Digitorum Communis (EDC) splitting approach allows possible wide surgical exposure and low risk of LUCL damage. The comparison of PIN injury during surgical dissection among these 3 common lateral approaches was not previously evaluated. We aim to determine the anatomical proximity of the PIN in these 3 common lateral elbow approaches and to define a safe zone of dissection for the surgical exposure. Methods. Cadaveric dissections of 9 pairs of fresh frozen adult upper extremities were performed using EDC splitting, Kaplan and Kocher approach to the radial head sequentially in a randomised order. The radial head and PIN were exposed. A mark was made on the radial head upon the initial exposure during dissection. Measurements from the marked point of the radial head to the PIN were made. Study has been approved by the ethics committee. Results. The EDC splitting approach is associated with a significantly lower chance of encountering the PIN along the entry of dissection to reach the radial head as compared to the Kaplan approach. The Kocher approach has a lower chance of encountering the PIN along the entry of dissection to reach the radial head as compared to both Kaplan and EDC splitting approach. Conclusions. The EDC splitting approach provides adequate exposure without injury to the lateral ligamentous complex nor need to elevate or retract the EDC and ECU muscle mass that could risk injuring the PIN. The Kaplan approach should be done by experienced surgeons who are familiar with the anatomy in this region, with extreme caution due to proximity of the point of entry to the PIN. Level of evidence. IV

Introduction. A deep squat (DS) is a challenging motion at the level of the hip joint generating substantial reaction forces (HJRF). During DS, the hip flexion angle approximates the functional range of hip motion. In some hip morphologies this femoroacetabular conflict has been shown to occur as early as 80° of hip flexion. So far in-vivo HJRF measurements have been limited to instrumented hip implants in a limited number of older patients performing incomplete squats (< 50° hip flexion and < 80° knee flexion). Clearly, young adults have a different kinetical profile with hip and knee flexion ranges going well over 100 degrees. Since hip loading data on this subgroup of the population is lacking and performing invasive measurements would be unfeasible, this study aimed to report a personalised numerical model solution based on inverse dynamics to calculate realistic in silico HJRF values during DS. M&M. Fifty athletic males (18–25 years old) were prospectively recruited for motion and morphological analysis. DS motion capture (MoCap) acquisitions and MRI scans of the lower extremities with gait lab marker positions were obtained. The AnyBody Modelling System (v6.1.1) was used to implement a novel personalisation workflow of the AnyMoCap template model. Bone geometries, semi-automatically segmented from MRI, and corresponding markers were incorporated into the template human model by an automated nonlinear morphing. Furthermore, a state-of-the-art TLEM 2.0 dataset, included in the Anybody Managed Model Repository (v2.0), was used in the template model. The subject-specific MoCap trials were processed to compute squat motion by resolving an overdeterminate kinematics problem. Inverse dynamics analyses were carried out to compute muscle and joint reaction forces in the entire body. Resulting hip joint loads were validated with measured in-vivo data from Knee bend trials in the OrthoLoad library. Additionally, anterior pelvic tilt, hip and knee joint angles were computed. Results. A preliminary set of results (20 out of 50 subjects) was analysed. The average HJRF was 3.42 times bodyweight at the peak of DS (95% confidence interval: 2.99 – 3.85%BW). Maximal hip and knee flexion angles were 113° (109.7°–116.8°) and 116° (109.4 – 123.0°) respectively. The anterior pelvic tilt demonstrated a biphasic profile with peak value of 33° (28.1° – 38.4°). Discussion. A non-invasive and highly personalised alternative for determining hip loading was presented. Consistently higher HJR forces during DS in young adults were demonstrated as opposed to the Orthoload dataset. Similarly, knee and hip flexion angles were much higher, which could support the increase in HJRF. We can conclude that DS hip kinetics in young adults clearly differ from the typical total hip arthroplasty population

Patients with osteoarthritis (OA) of the knee commonly alter their movement to compensate for deficiencies. This study presents a new numerical procedure for classifying sit-to-walk (STW) movement strategies. Ten control and twelve OA participants performed the STW task in a motion capture laboratory. A full body biomechanical model was used. Participants were instructed to sit in a comfortable self-selected position on a stool height adjusted to 100% of their knee height and then stand and pick up an object from a table in front of them. Three matrices were constructed defining the progression of the torso, feet and hands in the sagittal plane along with a fourth expressing the location of the hands relative to the knees. Hierarchical clustering (HC) was used to identify different strategies. Trials were also classified as to whether the left (L) and right (R) extremities used a matching strategy (bilateral) or not (asymmetrical). Fisher's exact test was used to compare this between groups. Clustering of the torso matrix dichotomised the trials in two major clusters; subjects leaning forward (LF) or not. The feet and hands matrices revealed sliding the foot backward (FB) and moving an arm forward (AF) strategies respectively. Trials not belonging in the AF cluster were submitted to the last HC of the fourth matrix exposing three additional strategies, the arm pushing through chair (PC), arm pushing through knee (PK) and arm not used (NA). The control participants used the LF+FBR+PK combination most frequently whereas the OA participants used the AFR+PCL. OA patients used significantly more asymmetrical arm strategies, p=0.034. The results demonstrated that control and OA participants favour different STW strategies. The OA patients asymmetrical arm behaviour possibly indicates compensating for weakness of the affected leg. These strategy definitions may be useful to assess post-operative outcomes and rehabilitation progress

Objectives

The surface of pure titanium (Ti) shows decreased histocompatibility over time; this phenomenon is known as biological ageing. UV irradiation enables the reversal of biological ageing through photofunctionalisation, a physicochemical alteration of the titanium surface. Ti implants are sterilised by UV irradiation in dental surgery. However, orthopaedic biomaterials are usually composed of the alloy Ti6Al4V, for which the antibacterial effects of UV irradiation are unconfirmed. Here we evaluated the bactericidal and antimicrobial effects of treating Ti and Ti6Al4V with UV irradiation of a lower and briefer dose than previously reported, for applications in implant surgery.

We used a biodegradable mesh to convert an acetabular defect into a contained defect in six patients at total hip replacement. Their mean age was 61 years (46 to 69). The mean follow-up was 32 months (19 to 50). Before clinical use, the strength retention and hydrolytic in vitro degradation properties of the implants were studied in the laboratory over a two-year period. A successful clinical outcome was determined by the radiological findings and the Harris hip score.

All the patients had a satisfactory outcome and no mechanical failures or other complications were observed. No protrusion of any of the impacted grafts was observed beyond the mesh. According to our preliminary laboratory and clinical results the biodegradable mesh is suitable for augmenting uncontained acetabular defects in which the primary stability of the implanted acetabular component is provided by the host bone. In the case of defects of the acetabular floor this new application provides a safe method of preventing graft material from protruding excessively into the pelvis and the mesh seems to tolerate bone-impaction grafting in selected patients with primary and revision total hip replacement.