Elevated fat pads on a paediatric elbow radiograph may represent an intraarticular fracture. If no obvious fracture is visible, the injury may be treated with a collar and cuff until discomfort resolves. In some centres these patients are discharged directly from A&E, easing the load on fracture clinics and reducing the number of visits required by the patient. A retrospective study was carried out to review patient journey for children referred to clinic with elevated fat pads only and to investigate whether such a protocol could be established locally. Notes for all children attending fracture clinic in May 2018 were reviewed. X-rays for patients with any elbow injury were then reviewed. Patients with raised fat pads only were included in the study. Outcome following clinic review was recorded. 818 patients (315 new referrals) attended 15 clinics. 31 were referred with raised fat pads only. Mean age was 7.7 years with mean time to clinic of 4 days. 74.2% required no further treatment and were discharged at first clinic appointment. 8 patients were kept in cast for another 1–2 weeks due to parental apprehension, patient apprehension or patient being uncomfortable without cast. None of our patients required surgical intervention or re-attended following discharge. This study showed that patients with raised fat pads only can be treated with collar and cuff, analgesia and discharged from A&E with an advice leaflet. This would reduce the number of patients unnecessarily attending clinics thereby reducing patient distress and enabling more efficient use of clinic appointments

Aims. The aim of this study was to assess whether it is possible to predict the mortality, and the extent and time of neurological recovery from the time of the onset of symptoms and MRI grade, in patients with the cerebral fat embolism syndrome (CFES). This has not previously been investigated. Methods. The study included 34 patients who were diagnosed with CFES following trauma between 2012 and 2018. The clinical diagnosis was confirmed and the severity graded by MRI. We investigated the rate of mortality, the time and extent of neurological recovery, the time between the injury and the onset of symptoms, the clinical severity of the condition, and the MRI grade. All patients were male with a mean age of 29.7 years (18 to 70). The mean follow-up was 4.15 years (2 to 8), with neurological recovery being assessed by the Glasgow Outcome Scale and the Mini-Mental State Examination. Results. In all, seven who had early-onset CFES (< 24 hours), and a severe Takahashi grade on MRI, died. There was a significant association between the time of onset of neurological signs and mortality (p = 0.035). Mortality was also significantly associated with a severe Takahashi grade (p < 0.001). Among the 27 surviving patients, 26 (96.3%) recovered completely. One (3.7%) had a cognitive deficit. The mean time to recovery was 4.7 weeks (2 to 13), with late recovery aftereight eight weeks being recorded in three patients. Conclusion. There was a significantly increased rate of mortality in patients with CFES who had an early onset of symptoms and a severe grade on MRI. Complete neurological recovery can be expected in most patients with CFES who survive. Cite this article: Bone Joint J 2022;104-B(1):142–149

Introduction. Obesity has been associated with higher complication rates and poorer outcomes following joint replacement surgery. Body mass index (BMI) is a simple index of body composition and forms part of preoperative assessment. It does not take into account the proportion of lean mass and body fat and can give a false impression of body composition in healthy manual workers. A more accurate measure of body composition is available using non-invasive bioimpedance methods. This study aims to identify whether BMI provides an accurate measure of body fat composition in patients awaiting lower limb arthroplasty surgery. Methods. Consecutive patients attending for pre-assessment clinic prior to total knee and hip replacement surgery were examined. All patients had their BMI calculated and underwent bioimpedance testing using a bedside Bodystat 1500 scanner (Bodystat, UK). Results. 83 patients (28 male) were included. Mean age was 68 years (range 16 to 92). All were awaiting lower limb arthroplasty surgery (39 primary total hip replacement, 4 revision total hip replacement, 38 primary total knee replacement, one unicompartmental knee replacement and one patellofemoral joint replacement). Mean BMI was 30.8 (range 20.8 to 48.9). Mean body fat percentage was 37.4% (range 17% to 53.9%). A weak correlation was seen between the calculated BMI and the measured body fat percentage (r=0.42, Pearson's correlation coefficient). Mean body fat percentage in obese patients (BMI > 30; mean BMI 34.9; n=42) was 42% while in the non-obese patients (BMI < 30; mean BMI 26.6; n=41) was 32.8%. This difference was significant (p<0.001). Conclusion. In patients undergoing lower limb arthroplasty the calculated BMI has a weak correlation with the measured body fat percentage. Bedside, non-invasive bioimpedance analysis provides a quick and accurate measure of body composition and can be used during preoperative assessment. Future correlation of outcome against body composition and BMI will validate the use of body composition in these patients. Care should be taken when relying on BMI alone to assess body fat composition

Perivascular stem cells (PSCs) from lipoaspirate demonstrate increased purity and immaturity with greater engraftment potential than standard mesenchymal stem cells (MSCs). MSCs from the infra-patellar fat pad (IFP) have previously demonstrated increased chondrogenic potential. This study investigated the availability and potential of PSCs harvested from the infra-patellar fat pad of the human knee for musculoskeletal regeneration. Tissue sections of IFP were stained with markers for PSCs, MSCs and endothelial cells to confirm their presence and location. Samples were obtained from patients undergoing TKR (n=13) or ACL reconstructions (n=10). Pericytes and adventitial cells made up 3.8% and 21.2% respectively of the stromal vascular fraction. The total number of pericytes and adventitial cells were 4.6±2.2×104 and 16.2±3.2×104 respectively. Cells were cultured both separately and combined. Cell identity was ascertained using fluorescence-activated cell sorting, immunocytochemistry and PCR. Cultured PSCs were differentiated using chondrogneic, osteogenic, adipogenic and myogenic medias. Differentiation was determined using Alcian Blue, Alizarin red, Oil Red O and myosin staining. This study demonstrates that the IPFP is a viable source of PSCs that can be harvested either arthroscopically or through an arthrotomy by orthopaedic surgeons for cell-based musculoskeletal regeneration. Their potential now needs to be compared to conventional MSCs

Perivascular stem cells (PSCs) from lipoaspirate demonstrate increased purity and immaturity with greater engraftment potential than standard mesenchymal stem cells (MSCs). MSCs from the infra-patellar fat pad (IFP) have previously demonstrated increased chondrogenic potential. This study investigated the availability and potential of PSCs harvested from the infra-patellar fat pad of the human knee for musculoskeletal regeneration. Sections of IFP were stained with markers for PSCs, MSCs and endothelial cells to confirm their presence and location. Samples were obtained from patients undergoing TKR (n=13) or ACL reconstructions (n=10). Pericytes and adventitial cells made up 3.8% and 21.2% respectively of the stromal vascular fraction. The total number of pericytes and adventitial cells were 4.6±2.2×10. 4. and 16.2±3.2×10. 4. respectively. Cells were cultured both separately and combined. Cell identity was ascertained using fluorescence-activated cell sorting and immunocytochemistry. Cultured PSCs were differentiated using chondrogneic, osteogenic, adipogenic and myogenic medias. Differentiation was determined using Alcian Blue, Alizarin red, Oil Red O and mysosin staining. This study demonstrates that the IFP is a viable source of PSCs that can be harvested either arthroscopically or through an arthrotomy by orthopaedic surgeons for cell-based musculoskeletal regeneration. Their potential now needs to be compared to conventional MSCs

Aims. The objective of our study is to identify the causes for recurrence and to evaluate the results of our technique. Material and Methods. We retrospectively analysed 18 patients (12 females; 6 males) who had both clinical and electrophysiological confirmation (7 focal entrapments; 11 severe entrapments) of recurrent carpal tunnel syndrome. In all the patients, after releasing the nerve a vascularised fat pad flap was mobilised from hypothenar region and sutured to the lateral cut end of flexor retinaculum. All the patients were assessed post-operatively for relief of pain, recovery of sensory and motor dysfunction. Results. The average age was 61 years and dominant hand was involved in 13/18. The average time between the first and second surgery was fifty-nine months. Intra-operatively ten had completely reformed retinaculum, two partially reformed (proximally) and five had scar tissue between the cut ends and one had scar tissue and fibrosis around the nerve. All patients had improvement of symptoms post-operatively. Ten had complete recovery immediately after surgery, the remaining patients had severe focal entrapment and had scar tissue intraoperatively. The patients with delayed recovery had high incidence of a) Early recuurence (average of nine months), b) Diabetes mellitus c) Obese/over-weight and d) cervical spine problems. Conclusions. The hypothenar fat pad transposition flap provides a reliable source of vascularised local tissue that prevents scar formation and helps nerve gliding. 80% of the patients in whom recurrence occurred within a year are associated with poor outcome/delayed recovery

Mesenchymal stem cells (MSCs) reside around blood vessels in all organs. This reservoir of progenitors can be ‘recruited’ in response to injury. The ability to manipulate stem cells therapeutically within injured tissue provides an attractive alternative to transplantation. Stem cells are regulated by neighbouring cells. We hypothesized that endothelial cells (ECs) influence MSC differentiation into bone and fat. MSCs were sorted from fat using fluorescent activated sorting. Their capacity to differentiate into bone, fat and cartilage was used to confirm MSC phenotype. MSCs and ECs were cultured in two-dimensions (standard culture dishes) and three-dimensions (vascular networks suspended in gel). Cocultures were exposed to osteogenic and adipogenic media. The role of EC-released factors on MSC differentiation was determined using a system in which cells share media but do not contact. Wnt pathway modulators were used to investigate the role of Wnt signalling. MSCs differentiated into bone, fat and cartilage. MSCs and ECs integrated in two- and three-dimensions. MSCs and ECs formed vessel-like structures in three-dimensions. When cultured with ECs, MSC differentiation to bone was accelerated while differentiation to fat was inhibited. This effect on osteogenesis was maintained when cells shared media but did not contact. Coculture with Wnt modulators confirmed that this effect is in part, mediated through Wnt signalling. Our data suggest that ECs influence MSC differentiation. Therapeutic targeting of EC-MSCs signalling may enable manipulation of MSCs in vivo avoiding the need for cell transplantation. This could enable trauma and orthopaedic patients who have healthy resident stem cells to self-repair

The role of mesenchymal stem cells (MSCs) in enhancing healing process has been examined with allogeneic and xenogeneic cells in transplantation models. However, certain factors might limit the use of allogeneic cells in clinical practice, (e.g. disease transmission, ethical issues and patient acceptance). Adipose tissue represents an abundant source for autologous cells. The aim of this study was to evaluate adipose-derived autologous cells for preventing non-union. Adults male Wistar rats (n=5) underwent a previously published surgical procedure known to result in non-union if no treatment is given. This consisted of a mid-shaft tibial osteotomy with peri/endosteal stripping stabilised by intramedullary nail fixation with a 1mm gap maintained by a spacer. During the same operation, ipsilateral inguinal subcutaneous fat was harvested and processed for cell isolation. After three weeks in culture, the cell number reached 5×106 and were injected into the fracture site. At the end of the experiment, all tibias (injected with autologous fat-MSCs) developed union. These were compared with a control group injected with PBS (n=4) and with allogenic (n=5) and xenogeneic (n=6) cell transplantation groups. The amount of callus was noticeably large in the autologous cell group and the distal-callus index was significantly greater than that of the other groups, P-value =<0.05, unpaired t-test, corrected by Benjamini & Hochberg. We report a novel method for autologous MSCs implantation to stimulate fracture healing. Local injection of autologous fat-MSCs into the fracture site resulted in a solid union in all the tibias with statistically significantly greater amounts of callus

Title

3D distribution of cortical bone thickness in the proximal humerus, implications for fracture management.

Aims

This study aimed to compare mortality in trochanteric AO/OTA A1 and A2 fractures treated with an intramedullary nail (IMN) or sliding hip screw (SHS). The primary endpoint was 30-day mortality, with secondary endpoints at 0 to 1, 2 to 7, 8 to 30, 90, and 365 days.

Deficiency in the gluteus medius and minimus abductor muscles is a well-recognised cause of hip pain and considerable disability. These patients present a management challenge, with no established consensus for surgical intervention. Whiteside in 2012 described a surgical technique for gluteus maximus tendon transfer, with successful outcomes reported. This study is the largest known case series to date of patients undergoing gluteus maximus tendon transfer with clinical and patient reported outcomes measured. 13 consecutive patients were included in the study. All patients had clinical evidence of abductor dysfunction together with MRI evidence of gluteal atrophy and fat infiltration. All patients underwent gluteus maximus transfer with surgery performed according to the procedure described by Whiteside. Patients were followed up with both clinical assessment and patient questionnaires conducted. Mean age was 69 (range 54–82) with 9 patients (69%) having previous Hardinge approach to the affected hip. 6 patients (46%) reported they were satisfied overall with the procedure and 5 patients (38%) were unsatisfied. 7 patients (54%) had improvements in visual analogue scale of pain and 5 patients (54%) reported overall improvements in function. Mean Oxford Hip Score on follow up was 20/48 (range 5–48) and trendelenberg test was positive in 11 patients (85%). No differentiating variable could be identified between patients with positive and negative outcomes (Assessed Variables: Age, sex, BMI, aetiology and gluteus maximus muscle thickness). Clinical outcomes were varied following gluteus maximus tendon transfer for chronic hip abductor dysfunction. Results are considerably less promising than pre-existing studies would suggest

Background. Tears of the rotator cuff are a common pathology and poorly understood. Achieving a good functional outcome for patients may be difficult, and the degree of fat infiltration into the muscle is known to be a major determining factor to surgical repair and post operative function. It is the hypothesis of this study that the degree of retraction of the common central tendon as seen on MRI corresponds to the amount of fat infiltration classified according to the Goutallier grading System. Methods. MRI scans of the supraspinatus were reviewed and two groups identified: no tear (NT) and full thickness tear (FTT). The following measures were taken: central tendon retraction (CTR) and the Goutallier Grade according to MRI. The difference between Goutallier grade between NT and FTT were measured using the Mann-Whitney test. The relationship between Goutallier grade and increasing amount of CTR was described using Spearman's rank correlation and differences assessed using Mann-Whitney tests. Results. 143 scans had NT and 148 scans had FTT after exclusion and inclusion criteria were satisfied. All FTT involved the central tendon, with varying retraction. 143 in the NT group were Goutallier Grade 0–1. FTT revealed 2 Grade 0, 21 Grade 1, 35 Grade 2, 14 Grade 3, 76 Grade 4. The difference in Goutallier grade between the NT and FTT was highly significant (p<0.001). The increase in Goutallier grade associated with increasing retraction of the central tendon was also highly significant p<0.001. Conclusion. CTR can be directly linked to Goutallier grading and as such may help to determine surgical intervention between groups. Level of Evidence. Level 1 Diagnostic Study

Aims

Heterotopic ossification (HO) is a common complication after elbow trauma and can cause severe upper limb disability. Although multiple prognostic factors have been reported to be associated with the development of post-traumatic HO, no model has yet been able to combine these predictors more succinctly to convey prognostic information and medical measures to patients. Therefore, this study aimed to identify prognostic factors leading to the formation of HO after surgery for elbow trauma, and to establish and validate a nomogram to predict the probability of HO formation in such particular injuries.

Exercise deters systemic diseases such as osteoporosis, sarcopenia, diabetes and obesity. Brief daily periods of low intensity vibration (LIV; <0.4g) is anabolic to bone and muscle, an adaptive response achieved in part by biasing mesenchymal stem cell (MSC) fate selection towards forming higher order connective tissues. In the clinic, LIV has protected the musculoskeletal system even under severe challenges such as Crohn Disease, Cerebral Palsy, and end-stage renal disease. Low magnitude mechanical signals also suppress adipogenesis in the mouse, with reductions in subcutaneous and visceral fat. The starkly distinct response of these tissues (augment bone & muscle; suppress fat) suggests that LIV influences the differentiation pathway of MSCs. Extending this diet induced obesity model to 7 months increased total adiposity, accelerated age-related loss of trabecular bone and severely reduced B & T-cell number in the marrow and blood, shifting hematopoietic stem cells (HSC) towards the myeloid lineage. LIV introduced at 4 months rescued bone and B-cells to those levels measured in regular diet controls. These data emphasise why inactivity can promote osteoporosis, diabetes and obesity, and why a sedentary individual is predisposed to disease sequelae. Protection of MSC and HSC populations by mechanical signals may represent a unique strategy by which adiposity can be suppressed, the immune system protected, and a musculoskeletal system enhanced

Anterior knee pain post Total knee Replacement (TKR) has been reported to be as high as 49%. The source is poorly understood; both the peripatellar soft tissues and the infrapatellar fat pad have been implicated. Immunohistochemical studies demonstrate hyperinnervation of the peripatellar soft tissues. In theory circumferential electrocautery denervates the patella. However there is little evidence that this practice translates into improved clinical outcomes. This study aimed to find the effect on clinical outcome, of intraoperative circumpatellar electrocautery in patients undergoing TKR. 200 patients undergoing primary TKR were randomised to circumferential circumpatellar electrocautery or nothing. Patients were assessed for Visual (VAS) for anterior knee pain and Oxford Knee Score (OKS) preoperatively, 3 months, 6 months and 1 year post-procedure. Patients and assessors were blinded to treatment allocation until the end of the study. There were 91 patients in the electrocautery group and 94 controls. The mean VAS improvement from pre-op to one year was 3.8 in both groups. The mean improvement in OKS was 16.6 points in the control and 17.7 in the electrocautery group (p= 0.40). There were no significant differences between the two groups in terms of VAS or OKS at any other time. Although previous studies have conflicting outcomes, to our knowledge this is the first prospective randomised controlled blinded trial of significant power, to evaluate the effect of peripatellar diathermy in TKR. We conclude that denervation electrocautery of the patella makes no difference to the clinical outcomes of TKR

The imaging techniques available to aid the diagnosis of ruptures of tendo Achillis, the rotator cuff and the tendon of tibialis posterior in rheumatoid patients are well described. However, ruptures of tendon or muscle at other sites are uncommon and may be overlooked. Diagnosis is often made by localised tenderness, swelling and a lack of active movement associated with a palpable defect. Clinical examination may be inconclusive and can be aided by imaging studies. We report two cases in which ruptures of a tendon were suspected, and ultrasound imaging demonstrated the palpable defect to be a cleavage plane in the subcutaneous fat – a ‘fat fracture’

Introduction. There is a challenge to detect partial tear of the ACL, the number of bundle injured and the proportion of fibers torn. The MRI was shown efficient to individualize the two anteromedial (AM) and posterolateral (PL) bundles of the ACL. The purpose of this study was to assess the ability of the MRI to detect partial tears of the ACL on axial views to display the AM and PL bundles. Materials and methods. This retrospective study included 48 patients (19 partial tears of the ACL, 16 complete rupture of the ACL and 13 normal knee) who underwent both arthroscopy and MRI examinations of the knee. The conventional MRI protocol included one sagittal T1- weighted sequence and 3 proton-density fat sat. The images from MRI were analysis by a radiologist specialized in musculoskeletal imaging who was blinding to the arthroscopic findings. The criteria for the analysis of MRI were divided into primary (those involving the ACL himself) and secondary signs (associated abnormalities). The primary signs included the horizontalisation of the ACL (ACL axis), the global ACL signal intensity and the signal intensity of each AM and PL bundle. The secondary signs included bone bruise, osteochondral impaction, popliteus muscle injury, medial collateral ligament injury and joint effusion. The ACL was classified as normal, partially or totally torn. The rupture of the AM and PL bundle was specified. Results. In our study, MRI was found to have a 75% sensitivity and a 73% specificity for the diagnosis of partial tears of the ACL. The sensitivity to detect AM bundle lesion was 88% but the specificity was 50%. The lack of horizontalisation of the ACL was a very good sign, for partial tears of the ACL, with a sensitivity of 84% and a specificity of 81% (p<0.05). Regarding the secondary signs, there was no significant difference to distinguish partial and complete tear. However, we found that there was a greater probability to find a partial tear of the ACL with the lack of joint effusion, bone bruise and medial collateral ligament injury. Quantifying the proportion of injured fibers was unsuccessful and was found as a failure of the MRI. Conclusions. MRI exhibited lower sensitivity and specificity for partial tear than for complete rupture of the ACL. However 3 important arguments can guide us: the lack of horizontalisation of the ACL, a continuous ACL signal, the display of one of two bundles on the axial view

INTRODUCTION. In order to address high failure rates following rotator cuff repairs, a greater understanding is required of the underlying structural changes so that treatments can be appropriately targeted and biomarkers of failure can be identified. As collagen is the primary constituent of tendon and determines force transmission, collagen structural changes may affect responses to loading. For example changes in collagen 1 and 5 are associated with the hyperelastic Ehlers-Danlos syndrome, which is diagnosed by looking for pathopneumonic altered collagen fibres or ‘collagen flowers’ in skin using transmission electron microscopy (TEM). To date no study has been performed on the microstructure of torn human rotator cuff tendons using TEM. It was hypothesized that normal, small and massive human rotator cuff tendons tears will have altered microscopic structures. The unique study aimed to use TEM to compare the ultrastructure of small and massive rotator cuff tears, to normal rotator cuff tendons. METHODS. Samples from 7 human rotator cuff tendons repairs were obtained, including 4 massive (>5 cm) and 3 small (< 1 cm) tears, and 3 matched normal controls with no history of connective tissue disorders. Specimens were fixed in 4% glutaraldehyde in 0.1M phosphate buffer, processed and examined blind using routine TEM examination. To assess whether changes in the relative expression of collagen 1 and 5 (COL1A1, COL5A1 and COL5A2) occurred in all tears, qPCR was performed on another 6 phenotypically matched patients. RESULTS. The basic structure of the normal tendon consisted of tightly packed clumps of dense packed parallel running collagen fibers with few fibroblasts and small amounts of fine filamentous material between clumps. In contrast, torn samples were more variable with areas of less dense packing of collagen fibers and larger areas of filamentous material plus variable numbers of lipid droplets both within the fibroblast and between the collagen bundles. There was also evidence of twisting and random orientation of individual collagen fibers. All torn tendons showed evidence of a proportion of the fibers within the collagen bundles being enlarged with a serrated outline, similar in appearance to ‘collagen flowers’. Clear differences between the small and massive tears were not identified. qRT-PCR of torn rotator cuff tendon specimens demonstrated no altered collagen expression compared to normal tendons. DISCUSSION. This novel study has identified the previously unreported presence of atypical collagen fibers with focal swelling resulting in the appearance of ‘collagen flowers’ in torn rotator cuff tendons only. This appearance is considered pathognomonic of Ehlers-Danlos syndrome, classical type 1 and 2. Torn tendons also showed an increase in filamentous material, and infiltration with fat droplets. These novel findings may offer insight into the mechanisms of structural damage that contribute to rotator cuff failure. Further examination is required, to evaluate the significance of these observations

Aims

Osseointegrated prosthetic limbs allow better mobility than socket-mounted prosthetics for lower limb amputees. Fractures, however, can occur in the residual limb, but they have rarely been reported. Approximately 2% to 3% of amputees with socket-mounted prostheses may fracture within five years. This is the first study which directly addresses the risks and management of periprosthetic osseointegration fractures in amputees.

Aims

Debate continues about whether it is better to use a cemented or uncemented hemiarthroplasty to treat a displaced intracapsular fracture of the hip. The aim of this study was to attempt to resolve this issue for contemporary prostheses.