Injection or aspiration of the ankle may be performed through either an anteromedial or an anterolateral approach for diagnostic or therapeutic reasons. We evaluated the success of an intra-articular puncture in relation to its site in 76 ankles from 38 cadavers. Two orthopaedic surgical trainees each injected methylene blue dye into 18 of 38 ankles through an anterolateral approach and into 20 of 38 through an anteromedial. An arthrotomy was then performed to confirm the placement of the dye within the joint. Of the anteromedial injections 31 of 40 (77.5%, 95% confidence interval (CI) 64.6 to 90.4) were successful as were 31 of 36 (86.1%, 95% CI 74.8 to 97.4) anterolateral injections. In total 62 of 76 (81.6%, 95% CI 72.9 to 90.3) of the injections were intra-articular with a trend towards greater accuracy with the anterolateral approach, but this difference was not statistically significant (p = 0.25). In the case of trainee A, 16 of 20 anteromedial injections and 14 of 18 anterolateral punctures were intra-articular. Trainee B made successful intra-articular punctures in 15 of 20 anteromedial and 17 of 18 anterolateral approaches. There was no significant difference between them (p = 0.5 and p = 0.16 for the anteromedial and anterolateral approaches, respectively). These results were similar to those of other reported studies. Unintended peri-articular injection can cause complications and an unsuccessful aspiration can delay diagnosis. Placement of the needle may be aided by the use of ultrasonographic scanning or fluoroscopy which may be required in certain instances

The anterolateral ligament (ALL) has been recently recognized as a distinct stabilizer for internal rotation in the ACL-deficient knee and it has been hypothesized that ALL reconstruction may play an important role in improving anterolateral instability following ACL reconstruction. Both the gracilis tendon (GT) and a portion of the iliotibial band (ITB) have been suggested as graft materials for ALL reconstruction, however, there is an ongoing debate concerning whether GT or ITB are appropriate grafting materials. Furthermore, there is limited knowledge in how the mechanical properties of these potential grafts compare to the native ALL. Consequently, the aim of this study was to characterize the elastic (Young's modulus and failure load) and viscoelastic (dynamic and static creep) mechanical properties of the ALL and compare these results with the characteristics of the grafting materials (GT and ITB), in order to provide guidance to clinicians with respect to graft material choice. Fourteen fresh-frozen cadaveric knees (85.2±12.2 yr) were obtained. The ALL, ITB, and the distal (GTD) and proximal gracilis tendons (GTP) (bisected at mid portion) were harvested from each donor and tested with a dynamic material testing frame. Prior to testing, the cross-sectional area of each tissue was measured using a casting method and the force required to achieve a min-max stress (1.2–12 MPa) for the testing protocol was calculated (preconditioning (20 cycles, 3–6 MPa), sinusoidal cycle (200 cycles, 1.2–12 MPa), dwell at constant load (100 s, 12 MPa), and load to failure (3%/s)). Kruskall-Wallis tests were used to compare all tissue groups (p<0.05). The Young's modulus of both ALL (181.3±63.9 MPa) and ITB (357.6±94.4 MPa) are significantly lower than GTD (835.4±146.5 MPa) and GTP (725.6±227.1 MPa). In contrast, the failure load of ALL (124.5±40.9 N) was comparable with GTD (452.7±119.3 N) and GTP (433±133.7 N), however, significantly lower than ITB (909.6±194.7 N). Dynamic creep of the ALL (0.5±0.3 mm) and ITB (0.7±0.2 mm) were similar (p>0.05) whereas the GTD (0.26±0.06 mm) and GTP (0.28±0.1 mm) were significantly lower. Static creep progression of the ALL (1.09±0.4 %) was highest across all tissues, while GTD (0.24±0.05 %) and GTP (0.25±0.0.04 %) were lowest and comparable with ITB (0.3±0.07 %) creep progression. Since grafts from the ITB, GTD and GTP were comparable to the ALL only for certain mechanical properties, there was no clear preference for using one over another for ALL reconstruction. Therefore, further studies should be performed in order to evaluate which parameters play a vital role to determine the optimum grafting choice

Background. The anatomy of the human body has been studied for centuries. Despite this, recent articles have announced the presence of a new knee ligament- the anterolateral ligament. It has been the subject of much discussion and media commentary. Previous anatomical studies indicate its presence, and describe its location, origin, course and insertion. Magnetic resonance imaging (MRI) is the best and most commonly used investigation to assess the ligamentous structure of the knee. To date, most MRI knee reports make no mention of the anterolateral ligament. The aim of this study was to assess for the presence of the anterolateral ligament using MRI, and to describe the structure if visualised. Methods. All right knee MRIs performed on a Siemens Magnetom Espree 1.5 Tesla scanner in Merlin Park Hospital over a 4 year period were retrospectively analysed. Patients born before 1970, or with reported abnormalities were excluded. The normal MRIs were then analysed by a consultant radiologist specialising in musculoskeletal imaging. Measurements on origin, insertion, course and length were noted. Results. 942 right knee MRIs were performed in the time period. 62 were classed as normal, and within the specified age range. 10 were randomly sampled. Of these the ligament was visible on all 10 MRIs, best viewed in the coronal plane. The average length (visible in 8/10) was 28.88mm +/− 5.14mm. The origin (visible in all 10) was 2.25mm +/− 0.39mm. The insertion (visible in 9/10) was 1.93mm +/− 0.424. The mid thickness was 1.87mm +/− 0.2mm. Conclusions. This study indicates that the ALL is a discrete, visible structure on MRI. This furthers the evidence of the presence of the ALL and also provides information that may be beneficial in future studies, and assessment of knee injuries. Level of evidence. 4

Background. Return to sports after anterior cruciate ligament reconstruction (ACLR) is multifactorial and rotational stability is one of the main concerns. Anterolateral ligament reconstruction (ALLR) has been recommended to enhance rotational stability. Purpose. To assess the effect of ALLR on return to sports. Study Design. Retrospective comparative cohort study;. Level of evidence: III. Methods. A total of 68 patients who underwent ACLR after acute ACL injury between 2015 and 2018 with a follow-up of at least 24 months were enrolled in the study. Patients with isolated ACLR (group ALL(-), n=41) were compared to patients with ACLR+ALLR (group ALL(+), n=27) in regard to subjective knee assessment via Tegner activity scale, Anterior Cruciate Ligament-Return to Sport after Injury (ACL-RSI) scale, Knee Documentation Committee (IKDC) form and Lysholm score. All tests were performed before the surgery, at 6 months and 24 months postoperatively. Results. Mean follow-up was 29.7±2.9 months for group ALL(-) and 31.6±3.0 for ALL(+) (p=0.587). Tegner, ACL-RSI and IKDC scores at last follow-up were significantly better in ALL(+) compared to ALL(-). There were no significant differences in isokinetic extensor strength and single-leg hop test results between the groups. 40 (97.6%) patients in ALL(-) and 27 (100%) in ALL(+) had a grade 2 or 3 pivot shift (p=0.812) preoperatively. Postoperatively, 28 (68.3%) patients in ALL(-) and 25 (92.6%) patients in ALL(+) had a negative pivot shift (p<0.001). 2 (5.9%) patients in ALL(-) and 1 (3.7%) patient in ALL(+) needed ACLR revision due to traumatic re-injury (p=0.165). There was no significant difference in the rate of return to any sports activity (87.8% in ALL(-) vs 88.9% in ALL(+); p=0.532), but ALL(+) showed a higher rate of return to the same level of sports activity (55.6%) than group ALL(-) (31.7%) (p=0.012). Conclusion. ACLR combined with ALLR provided a significantly higher rate of return to the same level sports activity than ACLR alone, probably due to enhanced rotational stability

Recent National Institute for Health and Care Excellence (NICE) guidance has advised against the continued use of the Thompson implant when performing hip hemiarthroplasty and recommended surgeons consider using the anterolateral surgical approach over a posterior approach. Our objective was to review outcomes from a consecutive series of Thompson hip hemiarthroplasty procedures performed in our unit and to identify any factors predicting the risk of complications. 807 Thompson hip hemiarthroplasty cases performed between April 2008 and November 2013 were reviewed. 721 (89.3%) were cemented and 86 (10.7%) uncemented. 575 (71.3%) were performed in female patients. The anterolateral approach was performed in 753 (93.3%) and the posterior approach with enhanced soft tissue repair in 54 (6.7%). Overall, there were 23 dislocations (2.9%). Dislocation following the posterior approach occurred in 13.0% (7 of 54) in comparison to 2.1% (16 of 753) with the anterolateral approach (odds ratio (OR) 8.5 (95% CI 2.8 to 26.3) p < 0.001). Surgeon grade and patient history of cognitive impairment did not have a significant impact on dislocation rate. Patients were discharged home in 459 cases (56.9%), to a care home or other hospital in 273 cases (33.8%). 51.8% (338 of 653) returned home within 30 days. 75 died during their admission (9.3%). 30-day mortality was 7.1% and 1-year mortality was 16.6%. Intraoperative fracture occurred in 15 cases (1.9%) of which 14 were cemented. Superficial or deep infection occurred in 33 cases (4.1%). We recommend against the continued use of the posterior approach in hip hemiarthroplasty, as enhanced soft tissue repair did not reduce dislocation rates to an acceptable level. Our findings, however, demonstrate satisfactory results for patients treated with the Thompson hip hemiarthroplasty performed through an anterolateral approach. We suggest that the continued use of the Thompson implant in a carefully selected patient cohort is justifiable

Background. Percutaneous vertebroplasty (PVP) is a well established procedure with respect to improved pain and function following vertebral compression fracture. Currently, there is no consensus on the optimal cement distribution within a treated vertebral body. The aim of this study was to determine the influence of two distinct patterns of cement distribution following PVP on patient reported outcome measures up to 1 year post procedure. Methods. A retrospective study was undertaken of 42 patients consecutively undergoing PVP of up to 3 levels by a sole operator. Immediate post-procedural CT scans were analysed with VOXAR MPR software to determine cement distribution in each treated vertebrae as one of two defined patterns -“anterolateral” or “diffuse”. Patients completed an EQ-5D questionnaire pre-procedure and at 1, 2, 6 and 12 months from the procedure. Results. A 97% follow up rate of questionnaire completion was achieved for 30 patients. There were 58 treated levels with PVP performed at all levels between T6 and L5. Twelve patients had an anterolateral fill pattern and 18 patients had a diffuse fill pattern. Statistically significant improvement occurred in in all EQ-5D domains except self care at almost all timepoints in the study group. In the anterolateral group, pain was significantly improved at 1 week, 2months, 6 months and 1 year compared with only at 1 year in the diffuse group. Conclusion. PVP leads to immediate and sustained improvement in quality of life. Lateral cement placement leads to greater pain relief in the short term compared with diffuse cement filling. Conflicts of Interest. None. Source of Funding. None. This abstract has not been previously published in whole or in part; nor has it been presented previously at a national meeting

Chondral defects in the knee have cartilage biomechanical differences due to defect size and orientation. This study examines how the tibiofemoral contact pressure is affected by increasing full-thickness chondral defect size on the medial and lateral condyle at full extension. Isolated full-thickness, square chondral defects increasing from 0.09cm. 2. to 1.0cm. 2. were created sequentially on the medial and lateral femoral condyles of six human cadaveric knees with intact ligaments and menisci. Chondral defects were created 1.0cm from the femoral notch posteriorly. The knees were fixed to a uniaxial load frame and loaded from 0N to 600N at full extension. Contact pressures between the femoral and tibial condyles were measured using pressure mapping sensors. The peak contact pressure was defined as the highest value in the 2.54mm. 2. area around the defect. The location of the peak contact pressure was determined relative to the centre of the defect. Peak contact pressure was significantly different between (4.30MPa) 0.09cm. 2. and (6.91MPa) 1.0cm. 2. defects (p=0.04) on the medial condyle. On the lateral condyle, post-hoc analysis showed differences in contact pressures between (3.63MPa) 0.09cm. 2. and (5.81MPa) 1.0cm. 2. defect sizes (p=0.02). The location of the stress point shifted from being posteromedial (67% of knees) to anterolateral (83%) after reaching a 0.49cm. 2. defect size (p < 0.01) in the medial condyle. Conversely, the location of the peak contact pressure point moved from being anterolateral (50%) to a posterolateral (67%) location in defect sizes greater than 0.49cm. 2. (p < 0.01). Changes in contact area redistribution and cartilage stress from 0.49cm. 2. to 1.0cm. 2. impact adjacent cartilage integrity. The location of the maximum stress point also varied with larger defects. This study suggests that size cutoffs exist earlier in the natural history of chondral defects, as small as 0.49cm. 2. , than previously studied, suggesting a lower threshold for intervention

The Pivot-shift test is a clinical test for knee instability for patinets with Anterior cruciate ligament (ACL), however the test has low inter-observer reliability. Dynamic radiostereometry (dRSA) imaging is a highly precise method for objective evaluation of joint kinematics. The purpose of the study was to quantify precise knee kinematics during Pivot-shift test by use of the non-invasive dynamic RSA imaging. Eight human donor legs with hemipelvis were evaluated. Ligament lesion intervention of the ACL was performed during arthroscopy and anterolateral ligament (ALL) section was performed as a capsular incision. Pivot-shift test examination was recorded with dRSA on ligament intact knees, ACL-deficient knees and ACL+ALL-deficient knees. A Pivot-shift pattern was identifyable after ligament lesion as a change in tibial posterior drawer velocity from 7.8 mm/s in ligament intact knees, to 30.4 mm/s after ACL lesion, to 35.1 mm/s after combined ACL-ALL lesion. The anterior-posterior drawer excursion increased from 2.8 mm in ligament intact knees, to 7.2 mm after ACL lesion, to 7.6 mm after combined lesion. Furthermore a change in tibial rotation was found, with increasing external rotation at the end of the pivot-shift motion going from intact to ACL+ALL-deficient knees. This experimental study demonstrates the feasibility of RSA to objectively quantify the kinematic instability patterns of the knee during the Pivot-shift test. The dynamic parameters found through RSA displayed the kinematic changes from ACL to combined ACL-ALL ligament lesion

Several studies have evaluated the risk of peroneal nerve (PN) injuries in all-inside lateral meniscal repair using standard knee magnetic resonance imaging (MRI) with the 30 degrees flexed knee position which is different from the knee position during actual arthroscopic lateral meniscal repair. The point of concern is “Can the risk of PN injury using standard knee MRIs be accurately determined”. To evaluate and compare the risk of PN injury in all-inside lateral meniscal repair in relation to both borders of the popliteus tendon (PT) using MRIs of the two knee positions in the same patients. Using axial MRI studies with standard knee MRIs and figure-of-4 with joint fluid dilatation actual arthroscopic lateral meniscal repair position MRIs, direct lines were drawn simulating a straight all-inside meniscal repair device from the anteromedial and anterolateral portals to the medial and lateral borders of the PT. The distance from the tip of each line to the PN was measured. If a line touched or passed the PN, a potential risk of iatrogenic injury was noted and a new line was drawn from the same portal to the border of the PN. The danger area was measured from the first line to the new direct line along the joint capsule. In 28 adult patients, the closest distances from each line to the PN in standard knee MRI images were significantly shorter than arthroscopic position MRI images (all p-values < 0.05). All danger areas assessed in the actual arthroscopic position MRIs were included within the danger areas as assessed by the standard knee MRIs. We found that the standard knee MRIs can be used to determine the risk of peroneal nerve injury in arthroscopic lateral meniscal repair, although the risks are slightly overestimated

Introduction. In tissue engineering, the establishment of sufficient vascularization is essential for tissue viability and functionality. Inadequate vascularization disrupts nutrients and oxygen supply. Nonetheless, regenerating intricate vascular networks represents a significant challenge. Consequently, research efforts devoted to preserving and regenerating functional vascular networks in engineered tissues are of paramount importance. The present work aims to validate a decellularisation process with preservation of the vascular network and extracellular matrix (ECM) components in fasciocutaneous flaps. Method. Five vascularized fasciocutaneous flaps from cadaveric donors were carefully harvested from the anterolateral thigh (ALT), preserving the main perforator of the fascia lata. The entire ALT flap underwent decellularization by perfusion using a clinically validated chemical protocol. Fluoroscopy and computed tomography (CT) were used to analyze the persistence of the vascular network within the flap, pre- and post-decellularization. Histological analysis, including hematoxylin and eosin staining, and quantitative DNA assessment evaluated decellularization efficacy. Further qualitative (immunohistochemistry, IHC) and quantitative analyses were conducted to assess the preservation of ECM components, such as collagen, glycosaminoglycans, and elastin. Result. On average, the ALT flap maintains 82% of the perfusion area (p = 0.094) post-treatment. Histological analysis confirmed decellularization efficacy and revealed structural rearrangement. Paired analysis revealed a significant decrease in DNA levels (<14.8 ng/mg of dry weight, p****< 0.0001) and well-maintained ECM. IHC indicated the persistence of elastine, collagen IV and laminin. Quantitative analysis confirmed elastin (p = 0.44) and collagen persistence (+74%, p*** = 0.001, albeit with a decrease in matrix glycosaminoglycans (-41%, p*** = 0.01). Conclusion. Decellularization effectively removed cells, while preserving the ECM overall and maintaining some vascular network integrity. Yet, further study is needed to validate these findings, involving microCT examination of the vascular network and its ability to support cell colonization and viability

In this study, we evaluated the labrum tear using radial sequence 3D Multiple Echo Recombined Gradient Echo (MERGE) MRI without arthrography based on modified Czerny's classification, comparing with actual arthroscopic findings. A total of 61 hips including 27 hips of femoroacetabular impingement (FAI), 19 hips of borderline development dysplasia of the hip (BDDH) and 15 hips of early stage osteoarthritis (OA) were enrolled this retrospective study. MRI findings evaluated in each three regions of interest; anterior region, anterolateral region, and lateral region. The cases with severe degeneration that is not concordant with any original Czerny's classification is defined as stage4. We compared MRI findings with arthroscopic findings and calculated the sensitivity, specificity, and likelihood ratio in terms of the existence of labrum tear. MRI findings revealed labrum tear more frequently in anterolateral than lateral (p<0.001). Especially in FAI group, labrum tear was more frequently observed by MRI in anterolateral than lateral (p=0.006). In comparison with MRI findings and arthroscopic findings, the sensitivity was 97%, specificity was 79% and likelihood ratio was 4.59 as average of all regions in terms of the existence of labrum tear. In each region, sensitivity and specificity was 97% and 50% in anterior, 97% and 100% specificity in anterolateral, 94% and 81% in lateral, respectively. Thus, MERGE MRI revealed excellent sensitivity and specificity for diagnosis of labrum tear, especially in anterolateral region. The cases with severely degenerated labrum were classified as newly defined stage 4, which was recognized frequently in OA cases

There is controversy regarding the effect of different approaches on recovery after THR. Collecting detailed relevant data with satisfactory compliance is difficult. Our retrospective observational multi-center study aimed to find out if the data collected via a remote coaching app can be used to monitor the speed of recovery after THR using the anterolateral (ALA), posterior (PA) and the direct anterior approach (DAA). 771 patients undergoing THR from 13 centers using the moveUP platform were identified. 239 had ALA, 345 DAA and 42 PA. There was no significant difference between the groups in the sex of patients or in preoperative HOOS Scores. There was however a significantly lower age in the DAA (64,1y) compared to ALA (66,9y), and a significantly lower Oxford Hip Score in the DAA (23,9) compared to PA(27,7). Step count measured by an activity tracker, pain killer and NSAID use was monitored via the app. We recorded when patients started driving following surgery, stopped using crutches, and their HOOS and Oxford hip scores at 6 weeks. Overall compliance with data request was 80%. Patients achieved their preoperative activity level after 25.8, 17,7 and 23.3 days, started driving a car after 33.6, 30.3 and 31.7 days, stopped painkillers after 27.5, 20.2 and 22.5 days, NSAID after 30.3, 25.7, and 24.7 days for ALA, DAA and PA respectively. Painkillers were stopped and preoperative activity levels were achieved significantly earlier favoring DAA over ALA. Similarly, crutches were abandoned significantly earlier (39.9, 29.7 and 24.4 days for ALA, DAA and PA respectively) favoring DAA and PA over ALA. HOOS scores and Oxford Hip scores improved significantly in all 3 groups at 6 weeks, without any statistically significant difference between groups in either Oxford Hip or HOOS subscores. No final conclusion can be drawn as to the superiority of either approach in this study but the remote coaching platform allowed the collection of detailed data which can be used to advise patients individually, manage expectations, improve outcomes and identify areas for further research

A complete cement mantle is important for the longevity of a total hip replacement. In the minimally-invasive direct anterior approach used at the Innsbruck University hospital, the femoral component has to be inserted into the femoral canal by an angulated movement. In a cadaver study, the quality and the extent of the cement mantle surrounding 13 Exeter femoral components implanted straight through a standard anterolateral transgluteal approach were compared with those of 13 similar femoral components implanted in an angulated fashion through a direct anterior approach. A third-generation cementing technique was used. The inner and outer contours of the cement mantles was traced from CT scans and the thickness and cross-sectional area determined. In no case was the cement mantle incomplete. The total mean thickness of the cement mantle was 3.62 mm (95% confidence interval 3.59 to 3.65). The mean thickness in the group using the minimally-invasive approach was 0.16 mm less than that in the anterolateral group. The distribution of the thickness was similar in the two groups. The mean thickness was less on the anteromedial and anterolateral aspect than on the posterior aspect of the femur. There is no evidence that the angulated introduction of Exeter femoral components in the direct anterior approach in cadavers compromises the quality, extent or thickness of the cement mantle

Introduction and Objective. Heterotopic ossification is the formation of extraskeletal mineralized tissue commonly associated with either trauma or surgery. While several mouse models have been developed to better characterize the pathologic progression of HO, no model currently exists to study HO of the hip, the most common location of acquired HO in patients. Owing to the unique biological mechanisms underpinning the formation of HO in different tissues, we sought to develop a model to study the post-surgical HO of the hip. Materials and Methods. Wild-type mice C57BL/6J mice were used to study the procedure outcomes, while Pdgfra-CreERT2;mT/mG and Scx-GFP reporter animals were used for the lineage tracing experiments (total n=16 animals, male, 12 weeks old). An anterolateral approach to the hip was performed. Briefly, a 2 cm incision was made centered on the great trochanter and directed proximal to the iliac crest and distally over the lateral shaft of the femur. The joint was then reached following the intermuscular plane between the rectus femoris and gluteus medius muscles. After the joint was exposed, the articular cartilage was removed using a micropower drill with a 1.2 mm reamer. The medius gluteus and superficial fascia were then re-approximated with Vicryl 5-0 suture (Ethicon Inc, Somerville, NJ) and skin was then closed with Ethilon 5-0 suture (Ethicon Inc). Live high resolution XR imaging was performed every 2 wks to assess the skeletal tissues (Faxitron Bioptics, Tucson, AZ). The images were then scored using the Brooker classification. Ex-vivo microCT was conducted using a Skyscan 1275 scanner (Bruker-MicroCT, Kontich, Belgium). 3D reconstruction and analysis was performed using Dragonfly (ORS Inc., Montreal, Canada). For the histological analysis of specimens, Hematoxylin and Eosin (H&E), modified Goldner's Trichrome (GMT) stainings were performed. Reporter activity was assessed using fluorescent imaging. Results. Substantial periarticular heterotopic bone was seen in all cases. A periosteal reaction and an initial formation of calcified tissue within the soft tissue was apparent starting from 4 wks after surgery. By XR, progressive bone formation was observed within the periosteum and intermuscular planes during the subsequent 8 weeks. Stage 1 HO was observed in 12.5% of cases, stage 2 in 62.5% of cases, and stage 3 HO in 25% of cases. 3D microCT reconstructions of the treated hip joints demonstrated significant de novo heterotopic bone in several location which phenocopy human disease. Heterotopic bone was observed in an intracapsular location, periosteal location involving the iliac bone and proximal femur, and intermuscular locations. Histological analyses further confirmed these findings. To assess the cells which gave rise to HO in this model, an inducible PDGFRα and constitutive Scx-GFP reporter mice were used. A dramatic increase in mGFP reporter activity was noted PDGFRα within the HO injury site, including in areas of new cartilage and bone formation. Scx-associated reporter activity increased in the soft tissue and periosteal periacetabular areas of injured hips. Conclusions. HO has a diverse set of pathologies, of which joint associated HO after elective surgery is the most common. Here, we present the first mouse model of hip dislocation and acetabular reaming that mimics elements of human periarticular HO. The diverse locations of HO after acetabular reaming (intracapsular, intermuscular and periosteal) suggests the activation of different and specific HO program after surgery. Such a field effect would be consistent with local trauma and inflammation, which is a well-studied contributor to HO genesis. Not surprisingly, joint-associated HO significantly derives from PDGFRα-expressing cells, which has been shown to similarly give rise to intramuscular and intratendinous HO

Abstract. Objectives. Three-dimensional visualisation of sonographic callus has the potential to improve the accuracy and accessibility of ultrasound evaluation of fracture healing. The aim of this study was to establish a reliable method for producing three-dimensional reconstruction of sonographic callus. Methods. A prospective cohort of ten patients with a closed tibial shaft fracture managed with intramedullary nailing were recruited and underwent ultrasound scanning at 2-, 6- and 12-weeks post-surgery. Ultrasound B-mode capture was performed using infrared tracking technology to map each image to a three-dimensional lattice. Using echo intensity, semi-automated mapping was performed by two independent reviewers to produce an anatomic three-dimensional representation of the fracture. Agreement on the presence of sonographic bridging callus on three-dimensional reconstructions was assessed using the kappa coefficient. Results. Nine of the ten patients achieved union at six months. At six weeks, seven patients had bridging callus at ≥1 cortex on the three-dimensional reconstruction; when present all united. Compared to radiographs, no bridging callus was present in any patient. Of the three patients lacking sonographic bridging callus, one went onto a nonunion (77.8%-sensitive and 100%-specific to predict union). At twelve weeks, nine patients had bridging callus at ≥1 cortex on three-dimensional reconstruction and all united (100%-sensitive and 100%-specific to predict union). Compared to radiographs, seven of the nine patients that united had bridging callus. Three-dimensional reconstruction of the anteromedial and anterolateral tibial surface was achieved in all patients, and detection of sonographic bridging callus on the three-dimensional reconstruction demonstrated substantial inter-observer agreement (kappa=0.78, 95% confidence interval 0.29–1.0, p=0.011). Conclusions. Three-dimensional fracture reconstruction can be created using multiple ultrasound images in order to evaluate the presence of bridging callus. This imaging modality has the potential to identify impaired healing at an early stage in fracture management. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Treatment of comminuted intraarticular calcaneal fractures remains controversial and challenging. Anatomic reduction with stable fixation has demonstrated better outcomes than nonoperative treatment of displaced intraarticular fractures involving the posterior facet and anterior calcaneocuboid joint (CCJ) articulating surface of the calcaneus. The aim of this study was to investigate the biomechanical performance of three different methods for fixation of comminuted intraarticular calcaneal fractures. Comminuted calcaneal fractures, including Sanders III-AB fracture of the posterior facet and Kinner II-B fracture of the CCJ articulating calcaneal surface, were simulated in 18 fresh-frozen human cadaveric lower legs by means of osteotomies. The ankle joint, medial soft tissues and midtarsal bones along with the ligaments were preserved. The specimens were randomized according to their bone mineral density to 3 groups for fixation with either (1) 2.7 mm variable-angle locking anterolateral calcaneal plate in combination with one 4.5 mm and one 6.5 mm cannulated screw (Group 1), (2) 2.7 mm variable-angle locking lateral calcaneal plate (Group 2), or (3) interlocking calcaneal nail with 3.5 mm screws in combination with 3 separate 4.0 mm cannulated screws (Group 3). All specimens were biomechanically tested until failure under axial loading with the foot in simulated midstance position. Each test commenced with an initial quasi-static compression ramp from 50 N to 200 N, followed by progressively increasing cyclic loading at 2Hz. Starting from 200 N, the peak load of each cycle increased at a rate of 0.2 N/cycle. Interfragmentary movements were captured by means of optical motion tracking. In addition, mediolateral X-rays were taken every 250 cycles with a triggered C-arm. Varus deformation between the tuber calcanei and lateral calcaneal fragments, plantar gapping between the anterior process and tuber fragments, displacement at the plantar aspect of the CCJ articular calcaneal surface, and Böhler angle were evaluated. Varus deformation of 10° was reached at significantly lower number of cycles in Group 2 compared to Group 1 and Group 3 (P ≤ 0.017). Both cycles to 10° plantar gapping and 2 mm displacement at the CCJ articular calcaneal surface revealed no significant differences between the groups (P ≥ 0.773). Böhler angle after 5000 cycles (1200 N peak load) had significantly bigger decrease in Group 2 compared to both other groups (P ≤ 0.020). From biomechanical perspective, treatment of comminuted intraarticular calcaneal fractures using variable-angle locked plate with additional longitudinal screws or interlocked nail in combination with separate transversal screws seems to provide superior stability as opposed to variable-angle locked plating only

Summary Statement. Repetitive loading of degenerated human intervertebral discs in combined axial compression, flexion and axial rotation, typical of manual handling lifing activities, causes: an increase in intradiscal maximum shear strains, circumferential annular tears and nuclear seperation from the endplate. Introduction. Chronic low back pain (LBP) is a crippling condition that affects quality of life and is a significant burden to the health care system and the workforce. The mechanisms of LBP are poorly understood, however it is well known that loss of intervertebral disc (disc) height due to degeneration is a common cause of chronic low back and referred pain. Gross disc injury such as herniation can be caused by sudden overload or by damage accumulation via repetitive loading, which is a cause of acute LBP and an accelerant of disc degeneration. The aim of this study was to determine for the first time the relationship between combined repetitive compression, flexion and axial rotation motion of degenerated cadaver lumbar spine segments, and the progression of three-dimensional (3D) internal disc strains that may lead to disc herniation and macroscopic tissue damage. Patients & Methods. Seven degenerated human lumbar functional spinal units (FSUs) underwent pre-test MRI, had a grid of tantalum wires inserted into the mid-transverse plane of the disc and were subjected to 20,000 cycles of repetitive loading in combined compression (1.7 MPa), flexion (11–13°) and right axial rotation (2–3°) in a six degree of freedom hexapod robot. Stereoradiographs were taken at cyclic intervals (1, 500, 1000, 5000, 10000, 15000 and 20000 cycles) from which 3D intradiscal principal strains and maximum shear strains (MSS) were calculated and partitioned into nine disc anatomical regions. After testing the discs underwent post-test MRI followed by macroscopic assessment to identify tissue damage. A repeated measures ANOVA having a within-subjects factor of cycle number, and a between-subjects factor of disc region was used to examine the effects of cycle number and disc region on MSS. Results. No visible evidence of disc herniation occurred after 20,000 cycles, however circumferential annular tears and nucleus separation from the endplate were observed in all specimens in agreement with observed signal changes in post-test MRI images. There was a significant effect of both cycle number, disc region and the interaction of cycle number x disc region on MSS (p<0.001). MSS was significantly larger after 20,000 cycles compared with the first loading cycle in the anterior, left anterolateral, left lateral, and left posterolateral disc regions (p<0.037). Minor changes in MSS were seen in the posterior and nucleus regions. The largest increases were observed in the left anterolateral and left posterolateral regions after 20,000 cycles. Discussion/Conclusion. A significant increase in MSS was observed across most regions in the disc after 20,000 repetitive loading cycles, especially in the left anterolateral and left posterolateral regions. No herniation was observed, although macroscopic and MRI evidence of circumferential annular tears and nuclear separation from the endplate occurred, suggesting internal disc tissue disorganisation that may indicate a progression towards eventual herniation

Osteonecrosis is a potentially devastating condition with poorly defined pathogenesis that can affect several anatomical areas with or without a previous traumatic insult. Post traumatic osteonecrosis (PON) in the foot and ankle has been commonly described in the talus and navicular but rarely in the distal tibia. PON of the distal tibia is a rarely reported and infrequent complication of fracture dislocations of the ankle. Its scarcity can lead to misdiagnosis and inappropriate management due to a lack of clinical knowledge or suspicion with resultant severe functional compromise. We aim to highlight the clinical and radiological features of PON of the distal tibia and report the findings in a series of four patients following a fracture dislocation of the ankle. Three patients sustained a SER4 fracture dislocation and one patient sustained a PER4 fracture dislocation in keeping with standard patterns of injury seen in most trauma units. In each case, PON of the distal tibia presented with progressive anterolateral tibial plafond collapse and valgus deformity of the ankle. The radiological features previously reported in the literature are based on plain film x-ray, CT and MRI but no description of SPECT-CT findings. One of the patients in the series underwent SPECT-CT following clinical suspicion of PON and thus we describe the findings not previously reported. Our objective is to highlight this rare condition as a potential cause for ongoing pain following fracture dislocation of the ankle as well as advocating the use of SPECT/CT as a useful imaging modality to aid in the diagnosis

Osteochondral lesions (OCLs) of the talus are a challenging and increasingly recognized problem in chronic ankle pain. Many novel techniques exist to attempt to treat this challenging entity. Difficulties associated with treating OCLs include lesion location, size, chronicity and problems associated with potential graft harvest sites. Matrix associated stem cell transplantation (MAST) is one such treatment described for larger lesions >15mm. 2. or failed alternative therapies. This cohort study describes a 5 year review of the outcomes of talar lesions treated with MAST. A review of all patients treated with MAST by a single surgeon was conducted. Pre-operative radiographs, MRIs and FAOS outcome questionnaire scores were conducted. Intraoperative classification was conducted to correlate with imaging. Post-operative outcomes included FAOS scores, return to sport, revision surgery/failure of treatment and progression to arthritis/fusion surgery. 32 patients were identified in this cohort. There were 10 females, 22 males, with an average age of 35. 01. 73% had returned and continued playing active sport. 23 patients underwent MAST in the setting of a failed previous operative attempt, with just 9 having MAST as a first option. 9 patients out of 32 had a further procedure. Two patients had a further treatment directed at their OCL. Two patients had a fusion, 2 had a cheilectomy at > 4 years for impingement, one had a debridement of their anterolateral gutter, one had debridement for arthrofibrosis, one patient had a re alignment calcaneal osteotomy with debridement of their posterior tibial tendon. MAST has demonstrated positive results in lesions which prove challenging to treat, even in a “failed microfracture” cohort

Introduction. The purpose of this study was to evaluate the outcome of vascularized iliac bone grafting for idiopathic osteonecrosis of the femoral head. Methods. We reviewed the clinical and radiological results of 35 operations performed on 29 patients who had osteonecrosis of the femoral head (ONFH) in which a pedicle iliac bone grafting was performed for minimum follow-up of 10 years. The average age was 35 years (range, 17 to 62 years). According to the Japanese Orthopaedic Association classification for ONFH, there were 28 stage 2, 7 stage 3-A, 17 type C-1 hips, and 18 type C-2 hips. After a bone tunnel of 1.5 × 5 cm was made in the anterior aspect of the femoral head and curettage of necrotic lesion was performed, the pedicle bone with the deep circumflex iliac artery (DCIA) was inserted into the anterolateral portion of the femoral head. The average follow-up period was 13 years and 6 months. Weight bearing was not allowed for 2 months after the operation. Survival rate of the femoral head was calculated by Kaplan-Meier methods, and collapse of the femoral head and configuration of the femoral head was investigated at final follow-up. Results. Collapse of the femoral head occurred in 19 hip joints of 35 studied. Although only 16 of 28 stage 2 hips showed collapse, all 7 stage 3 hips collapsed. Four of 17 hips (24%) showed collapse in patients with type C-1 necrosis, whereas, 15 of 18 hips (83%) developed collapse in patients with type C-2 necrosis. When the bone graft was inserted in the anterolateral portion of the femoral head, the incidence of collapse was reduced. In patients without collapse for more than 12 years, osteoarthritic change was evident in 5 hips between 12 to 19 years after operation. Conclusion. In this study, we found that collapse of the femoral head occurred or progressed in almost half of our patients, and these findings allowed us to clarify the operative indications for DCIA pedicle bone graft. In patients with stage 3, DCIA pedicle bone graft could not prevent collapse of the femoral head. While 13 of 17 hips with type C-1 were prevented from collapse, only 3 of 18 with type C-2 did not show collapse. These results indicate that DCIA bone graft may be indicated for stage 2, type C-1 necrosis. However, technical demands of this surgery tend to make it a less routine application for the treatment of ONFH