Discoid meniscus (DM) is a congenital variant of the knee joint that involves morphological and structural deformation, with potential meniscal instability. The prevalence of the Discoid Lateral Meniscus (DLM) is higher among the Asians than among other races, and both knees are often involved. Meniscal pathology is widely prevalent in the adult population, secondary to acute trauma and chronic degeneration. The true prevalence in children remains unknown, as pathologies such as discoid menisci often go undiagnosed, or are only found incidentally. A torn or unstable discoid meniscus can present with symptoms of knee pain, a snapping or clicking sensation and/or a decrease in functional activity, although it is not known if a specific presentation is indicative of a torn DM. While simple radiographs may provide indirect signs of DLM, magnetic resonance imaging (MRI) and arthroscopy is essential for diagnosis and treatment planning. Asymptomatic patients require close follow-up without surgical treatment, while patients with symptoms often require surgery. Partial meniscectomy is currently considered the treatment of choice for DLM. For children are more likely to achieve better results after partial meniscectomy

Abstract. Aims. The aim of this study was to evaluate the indications for patients presenting with knee pain undergoing magnetic resonance imaging of the knee prior to referral to the orthopaedic department and to ascertain whether plain radiograph imagining would be more beneficial prior to an MRI scan. Method. A retrospective review of all referrals received by the hospital over a 6-month period was performed. Patients with knee pain that underwent an MRI scan were classified into two age groups, under 50 years and over 50 years old. Patients having undergone Magnetic resonance imaging (MRI) prior to referral were identified, and findings of the scan were recorded. These patients were reviewed further to see if a plain radiograph had been completed prior to or after the MRI. Results. A total of 414 patients were referred. In the over 50's 228 MRI scans were performed. Of these 103/228 patients the predominate finding was meniscal tears and 72/228 had a finding of osteoarthritis. A plain radiograph of the knee was completed 99/228 cases, 28/99 before the MRI. In the under 50's 186 scans were performed and of these 85/186 the predominate finding was meniscal tears. A plain radiograph of the knee was completed in only eighty-three (83/186) cases, (69/83) before the MRI. Conclusion. In over 50s, 57% of patients (129 of 228) did not have a knee X-ray before having an MRI. For a single hospitals referral over 6 months these unnecessary MRI of knee cost the National Health Services £7,500

Pressure ulcers are a common occurrence in individuals with spinal cord injuries, and are attributed to prolonged sitting and limited mobility. This therefore creates the need to better understand soft tissue composition, in the attempt to prevent and treat pressure ulcers. In this study, novel approaches to imaging the soft tissue of the buttocks were investigated in the loaded and unloaded position using ultrasound (US) and magnetic resonance imaging (MRI). Twenty-six able-bodied participants (n=26, 13 males and 13 females) were recruited for this study and 1 male with a spinal cord injury. Two visits using US were required, as well as one MRI visit to evaluate soft tissue thickness and composition. US Imaging for the loaded conditions was performed using an innovative chair which allowed image acquisition in the seated upright position and MRI was done in the lateral decubitus position and loading was applied to the buttocks using a newly developed MRI compatible loader. The unloaded condition was a lateral decubitus position. Soft tissue was measured between the peak of the ischial tuberosity (IT) and the proximal femur and skin. Tissue thickness reliability for US was excellent, ICC=0.934–0.981 with no significant differences between the scan days. US and MRI measures of tissue thickness were significantly correlated (r=0.68–0.91). US underestimated unloaded tissue thicknesses with a mean bias of 0.39 – 0.56 for total tissue and muscle + tendon thickness. When the buttocks were loaded, total tissue thickness was reduced by 64.2±9.1%. US assessment of soft tissue thicknesses was reliable in both positions. The unloaded measurements using US were validated with MRI with acceptable limits of agreement, albeit tended to underestimate tissue thickness. Tissue thickness, but not fatty infiltration of muscle played a role in how the soft tissue of the buttocks responded to loading

Os acromiale is a developmental defect caused by failure of fusion of the anterior epiphysis of the acromion between the ages of 22 and 25. The prevalence of os acromiale in the general population ranges from 1.4% to 15%. Os acromiale has been reported as a contributory factor to shoulder impingement symptoms and rotator cuff injuries, despite being a common incidental observation. In this retrospective study, we examined the prevalence of os acromiale in black African patients with shoulder pain. We retrospectively reviewed the clinical records, radiographs, and magnetic resonance imaging (MRI) scans of 119 patients who presented with atraumatic and minor traumatic shoulder pain at a single institution over a one-year period. Anteroposterior, scapula Y-view, and axillary view plain images were initially evaluated for the presence of os acromiale, and this was corroborated with axial MRI image findings. Patients with verified os acromiale had their medical records reviewed to determine their first complaint and the results of their clinical examination and imaging examination. Radiographs and MRI on 24 patients (20%) revealed an osacromiale. This cohort had a mean age of 59.2 years, and there were significantly more females (65%) than males. Meso-acromion was identified as the most prevalent type (n=11), followed by pre-os acromion (n=7). All patients underwent bilateral shoulder x-rays, and 45 percent of patients were found to have bilateral meso- acromion. Most patients (70%) were reported to have unstable os acromiale with subacromial impingement symptoms, and nine patients (36%) had confirmed rotator cuff tears based on clinical and Mri findings. Surgery was necessary for 47% of the 24 patients with confirmed Os acromiale (arthroscopic surgery, n=7; open surgery, n=1) in order to treat their symptoms. The prevalence of os acromiale in our African patients with atraumatic shoulder symptoms is greater than that reported in the general population. Os acromiale is a rare condition that should always be considered when evaluating shoulder pain patients

Aim. Magnetic resonance imaging (MRI) and 2-[. 18. F]-fluoro-2-deoxy-D-glucose (. 18. F-FDG) Positron Emission Tomography, paired with Computed Tomography (PET/CT) are two indicated advanced imaging modalities in the complicated diagnostic work-up of osteomyelitis. PET/MRI is a relatively novel hybrid modality with suggested applications in musculoskeletal infection imaging. The goal of this study was to assess the value of hybrid . 18. F-FDG PET/MRI for chronic osteomyelitis diagnosis and surgical planning. Method. Five suspected chronic osteomyelitis patients underwent a prospective . 18. F-FDG single-injection/dual-imaging protocol with hybrid PET/CT and hybrid PET/MR. Diagnosis and relevant clinical features for the surgeon planning treatment were compared. Subsequently, 36 patients with . 18. F-FDG PET/MRI scans for suspected osteomyelitis were analysed retrospectively. Sensitivity, specificity, and accuracy were determined with the clinical assessment as the ground truth. Standardized uptake values (SUV) were measured and analysed by means of receiver operating characteristics (ROC). Results. The consensus diagnosis was identical for PET/CT and PET/MRI in the prospective cases, with PET/CT missing one clinical feature. The retrospective analysis yielded a sensitivity, specificity, and accuracy of 78%, 100%, and 86% respectively. Area under the ROC curve was .736, .755, and.769 for the SUVmax, target to background ratio, and SUVmax_ratio respectively. These results are in the same range and not statistically different compared to diagnostic value for . 18. F-FDG PET/CT imaging of osteomyelitis in literature. Conclusions. Based on our qualitative comparison, reduced radiation dose, and the diagnostic value that was found, the authors propose . 18. F-FDG PET/MRI as an alternative to . 18. F-FDG PET/CT in osteomyelitis diagnosis, if available

Aims. The aticularis genu (AG) is the least substantial and deepest muscle of the anterior compartment of the thigh and of uncertain significance. The aim of the study was to describe the anatomy of AG in cadaveric specimens, to characterize the relevance of AG in pathological distal femur specimens, and to correlate the anatomy and pathology with preoperative magnetic resonance imaging (MRI) of AG. Methods. In 24 cadaveric specimens, AG was identified, photographed, measured, and dissected including neurovascular supply. In all, 35 resected distal femur specimens were examined. AG was photographed and measured and its utility as a surgical margin examined. Preoperative MRIs of these cases were retrospectively analyzed and assessed and its utility assessed as an anterior soft tissue margin in surgery. In all cadaveric specimens, AG was identified as a substantial structure, deep and separate to vastus itermedius (VI) and separated by a clear fascial plane with a discrete neurovascular supply. Mean length of AG was 16.1 cm ( ± 1.6 cm) origin anterior aspect distal third femur and insertion into suprapatellar bursa. In 32 of 35 pathological specimens, AG was identified (mean length 12.8 cm ( ± 0.6 cm)). Where AG was used as anterior cover in pathological specimens all surgical margins were clear of disease. Of these cases, preoperative MRI identified AG in 34 of 35 cases (mean length 8.8 cm ( ± 0.4 cm)). Results. AG was best visualized with T1-weighted axial images providing sufficient cover in 25 cases confirmed by pathological findings.These results demonstrate AG as a discrete and substantial muscle of the anterior compartment of the thigh, deep to VI and useful in providing anterior soft tissue margin in distal femoral resection in bone tumours. Conclusion. Preoperative assessment of cover by AG may be useful in predicting cases where AG can be dissected, sparing the remaining quadriceps muscle, and therefore function. Cite this article: Bone Joint Open 2020;1-9:585–593

Increasing expectations from arthroscopic anterior cruciate ligament (ACL) reconstructions require precise knowledge of technical details such as minimum intra-femoral tunnel graft lengths. A common belief of having ≥20mm of grafts within the femoral tunnel is backed mostly by hearsay rather than scientific proof. We examined clinico-radiological outcomes in patients with intra-femoral tunnel graft lengths <20 and ≥20mm. Primary outcomes were knee scores at 1-year. Secondarily, graft revascularization was compared using magnetic resonance imaging (MRI). We hypothesized that outcomes would be independent of intra-femoral tunnel graft lengths. This prospective, single-surgeon, cohort study was conducted at a tertiary care teaching centre between 2015–2018 after obtaining ethical clearances and consents. Eligible arthroscopic ACL reconstruction patients were sequentially divided into 2 groups based on the intra-femoral tunnel graft lengths (A: < 20 mm, n = 27; and B: ≥ 20 mm, n = 25). Exclusions were made for those > 45 years of age, with chondral and/or multi-ligamentous injuries and with systemic pathologies. All patients were postoperatively examined and scored (Lysholm and modified Cincinnati scores) at 3, 6 and 12 months. Graft vascularity was assessed by signal-to-noise quotient ratio (SNQR) using MRI. Statistical significance was set at p<0.05. Age and sex-matched patients of both groups were followed to 1 year (1 dropout in each). Mean femoral and tibial tunnel diameters (P =0.225 and 0.595) were comparable. Groups A (<20mm) and B (≥20mm) had 27 and 25 patients respectively. At 3 months, 2 group A patients and 1 group B patient had grade 1 Lachman (increased at 12 months to 4 and 3 patients respectively). Pivot shift was negative in all patients. Lysholm scores at 3 and 6 months were comparable (P3= 0.195 and P6= 0.133). At 1 year both groups showed comparable Cincinnati scores. Mean ROM was satisfactory (≥130 degrees) in all but 2 patients of each group (125–130 degrees). MRI scans at 3 months and 1 year observed anatomical tunnels in all without any complications. Femoral tunnel signals in both groups showed a fall from 3–12 months indicating onset of maturation of graft at femoral tunnel. Our hypothesis, clinical and radiological outcomes would be independent of intra-tunnel graft lengths on the femoral aspect, did therefore prove correct. Intra-femoral tunnel graft lengths of <20 mm did not compromise early clinical and functional outcomes of ACL reconstructions. There seems to be no minimum length of graft within the tunnel below which suboptimal results should be expected

The opposable thumb is one of the defining characteristics of human anatomy and is involved in most activities of daily life. Lack of optimal thumb motion results in pain, weakness, and decrease in quality of life. First carpometacarpal (CMC1) osteoarthritis (OA) is one of the most common sites of OA. Current clinical diagnosis and monitoring of CMC1 OA disease are primarily aided by X-ray radiography; however, many studies have reported discrepancies between radiographic evidence of CMC1 OA and patient-related outcomes of pain and disability. Radiographs lack soft-tissue contrast and are insufficient for the detection of early characteristics of OA such as synovitis, which play a key role in CMC OA disease progression. Magnetic resonance imaging (MRI) and two-dimensional ultrasound (2D-US) are alternative options that are excellent for imaging soft tissue pathology. However, MRI has high operating costs and long wait-times, while 2D-US is highly operator dependent and provides 2D images of 3D anatomical structures. Three-dimensional ultrasound imaging may be an option to address the clinical need for a rapid and safe point of care imaging device. The purpose of this research project is to validate the use of mechanically translated 3D-US in CMC OA patients to assess the measurement capabilities of the device in a clinically diverse population in comparison to MRI. Four CMC1-OA patients were scanned using the 3D-US device, which was attached to a Canon Aplio i700 US machine with a 14L5 linear transducer with a 10MHz operating frequency and 58mm. Complimentary MR images were acquired using a 3.0 T MRI system and LT 3D coronal photon dense cube fat suppression sequence was used. The volume of the synovium was segmented from both 3D-US and MR images by two raters and the measured volumes were compared to find volume percent differences. Paired sample t-test were used to determine any statistically significant differences between the volumetric measurements observed by the raters and in the measurements found using MRI vs. 3D-US. Interclass Correlation Coefficients were used to determine inter- and intra-rater reliability. The mean volume percent difference observed between the two raters for the 3D-US and MRI acquired synovial volumes was 1.77% and 4.76%, respectively. The smallest percent difference in volume found between raters was 0.91% and was from an MR image. A paired sample t-test demonstrated that there was no significant difference between the volumetric values observed between MRI and 3D-US. ICC values of 0.99 and 0.98 for 3D-US and MRI respectively, indicate that there was excellent inter-rater reliability between the two raters. A novel application of a 3D-US acquisition device was evaluated using a CMC OA patient population to determine its clinical feasibility and measurement capabilities in comparison to MRI. As this device is compatible with any commercially available ultrasound machine, it increases its accessibility and ease of use, while proving a method for overcoming some of the limitations associated with radiography, MRI, and 2DUS. 3DUS has the potential to provide clinicians with a tool to quantitatively measure and monitor OA progression at the patient's bedside

Knee laxity following anterior cruciate ligament (ACL) injury is a complex phenomenon influenced by various biomechanical and anatomical factors. The contribution of soft tissue injuries – such as ligaments, menisci, and capsule – has been previously defined, but less is known about the effects of bony morphology. (Tanaka et al, KSSTA 2012) The pivot shift test is frequently employed in the clinical setting to assess the combined rotational and translational laxity of the ACL deficient knee. In order to standardise the maneuver and allow for reproducible interpretation, the quantitative pivot shift test was developed. (Hoshino et al, KSSTA 2013) The aim of this study is to employ the quantitative pivot shift test to determine the effects of bone morphology as determined by magnetic resonance imaging (MRI) on rotatory laxity of the ACL deficient knee. Fifty-three ACL injured patients scheduled for surgical reconstruction (36 males and 17 females; 26±10 years) were prospectively enrolled in the study. Preoperative magnetic resonance imaging (MRI) scans were reviewed by two blinded observers and the following parameters were measured: medial and lateral tibial slope, tibial plateau width, femoral condyle width, bicondylar width, and notch width. (Musahl et al. KSSTA 2012). Preoperatively and under anaesthesia, a quantitative pivot shift test was performed on each patient by a single experienced examiner. An image analysis technique was used to quantify the lateral compartment translation during the maneuver. Subjects were classified as “high laxity” or “low laxity” based upon the median value of lateral compartment translation. (Hoshino et al. KSSTA 2012) Independent t-tests and univariate logistic regression were used to investigate the relationship between the pivot shift grade and various features of bone morphology. Statistical significance was set at p<0.05. A high inter-rater reliability was observed in all MRI measurements of bone morphology (ICC=0.72–0.88). The median lateral compartment translation during quantitative pivot shift testing was 2.8mm. Twenty-nine subjects were classified as “low laxity” (2.8mm). The lateral tibial plateau slope was significantly increased in “high laxity” patients (9.3+/−3.4mm versus 6.1+/−3.7mm; p<0.05). No other significant difference in bone morphology was observed between the groups. This study employed an objective assessment tool – the quantitative pivot shift test – to assess the contribution of various features of bone morphology to rotatory laxity in the ACL deficient knee. Increased lateral tibial plateau slope was shown to be a significant independent predictor of high laxity. These findings could help guide treatment strategies in patients with high grade rotatory laxity. Further research into the role of tibial osteotomies in this sub-group is warranted

Introduction. Although total knee arthroplasty (TKA) is generally considered successful, 16–30% of patients are dissatisfied. There are multiple reasons for this, but some of the most frequent reasons for revision are instability and joint stiffness. A possible explanation for this is that the implant alignment is not optimized to ensure joint stability in the individual patient. In this work, we used an artificial neural network (ANN) to learn the relation between a given standard cruciate-retaining (CR) implant position and model-predicted post-operative knee kinematics. The final aim was to find a patient-specific implant alignment that will result in the estimated post-operative knee kinematics closest to the native knee. Methods. We developed subject-specific musculoskeletal models (MSM) based on magnetic resonance images (MRI) of four ex vivo left legs. The MSM allowed for the estimation of secondary knee kinematics (e.g. varus-valgus rotation) as a function of contact, ligament, and muscle forces in a native and post-TKA knee. We then used this model to train an ANN with 1800 simulations of knee flexion with random implant position variations in the ±3 mm and ±3° range from mechanical alignment. The trained ANN was used to find the implant alignment that resulted in the smallest mean-square-error (MSE) between native and post-TKA tibiofemoral kinematics, which we term the dynamic alignment. Results. Dynamic alignment average MSE kinematic differences to the native knees were 1.47 mm (± 0.89 mm) for translations and 2.89° (± 2.83°) for rotations. The implant variations required were in the range of ±3 mm and ±3° from the starting mechanical alignment. Discussion. In this study we showed that the developed tool has the potential to find an implant position that will restore native tibiofemoral kinematics in TKA. The proposed method might also be used with other alignment strategies, such as to optimize implant position towards native ligament strains. If native knee kinematics are restored, a more normal gait pattern can be achieved, which might result in improved patient satisfaction. The small changes required to achieve the dynamic alignment do not represent large modifications that might compromise implant survivorship. Conclusion. Patient-specific implant position predicted with MSM and ANN can restore native knee function in a post-TKA knee with a standard CR implant

When compared to magnetic resonance imaging (MRI), ultrasound (US) performed by experienced users is an inexpensive tool that has good sensitivity and specificity for diagnosing rotator cuff (RC) tears. However, many practitioners are now utilizing in-office US with little to no formal training as an adjunct to clinical evaluation in the management of RC pathology. The purpose of our study was to determine if US without formal training is effective in managing patients with a suspected RC tear. This was a single centre prospective observational study. Five fellowship-trained surgeons each examined 50 participants referred for a suspected RC tear (n= 250). Patients were screened prior to the consultation and were included if ≥ 40 years old, had an MRI of their affected shoulder, had failed conservative treatment of at least 6 months, and had ongoing pain and disability. Patients were excluded if they had glenohumeral instability, evidence of major joint trauma, or osteonecrosis. After routine clinical exam, surgeons recorded their treatment plan (“No Surgery”, “Uncertain”, or “Surgery”). Surgeons then performed an in-office diagnostic US followed by an MRI and documented their treatment plan after each imaging study. Interrater reliability was analyzed using a kappa statistic to compare clinical to ultrasound findings and ultrasound findings to MRI, normal and abnormal categorization of biceps, supraspinatus, and subscapularis. Following clinical assessment, the treatment plan was recorded as “No Surgery” in 90 (36%), “Uncertain” in 96 (39%) of cases, “Surgery” in 61 (25%) cases, and incomplete in 3 (2%). In-office US allowed resolution of 68 (71%) of uncertain cases with 227 (88%) of patients having a definitive treatment plan. No patients in the “No Surgery” group had a change in treatment plan. After MRI, 16 (6%) patients in the “No Surgery” crossed-over to the “Surgery” group after identification of full-thickness tears, larger than expected tears or alternate pathology (e.g., labral tear). The combination of clinical examination and in-office US may be an effective method in the initial management of patients with suspected rotator cuff pathology. Using this method, a definitive diagnosis and treatment plan was established in 88% of patients with the remaining 12% requiring an MRI. A small percentage (6%) of patients with larger than expected full-thickness rotator cuff tears and/or alternate glenohumeral pathology (e.g., labral tear) would be missed at initial evaluation

The anterolateral ligament (ALL) is considered as an important stabilizer of the knee joint. This ligament prevents anterolateral subluxation of the proximal tibia on the femur when the knee is flexed and internally rotated. Injury of the ALL was not investigated in patients with knee dislocation. The aim of the current research is to study the prevalence and characteristics of ALL injury in dislocated knees. A retrospective review of charts and radiological images was done for patients who underwent multiligamentous knee reconstruction surgery for knee dislocation in our institution from May 2008 to December 2016. Magnetic resonance imaging (MRI) was used to describe the ALL injury. The association of ALL injury with other variables related to the injury and the patient's background features was examined. Forty-eight patients (49 knees) were included. The mean age of the patients was 32.3 ± 10.6 years. High energy trauma was the mechanism of dislocation in 28 (57.1%) knees. Thirty-one knees (63.3%) were classified as knee dislocation (KD) type IV. Forty-five (91.8%) knees had a complete ALL injury and three (6.1%) knees had incomplete ALL injury. Forty (81.6%) knees had a complete ALL injury at the proximal fibres of the ALL, while 23 (46.9%) knees had complete distal ALL injury. None of the 46 (93.9%) knees with lateral collateral ligament (LCL) injury had normal proximal ALL fibres (p = 0.012). Injury to the distal fibres of the ALL, as well as overall ALL injury, were not associated with any other variables (p >0.05). Moreover, all patients with associated tibial plateau fractures (9, 18.4%) had abnormality of the proximal fibres of the ALL (p = 0.033). High grade ALL injury is highly prevalent among dislocated knees. The outcomes of reconstructing the ALL in multiligamentous knee reconstruction surgery should be investigated in future studies

Lymph node metastasis are a rare occurrence in soft tissue sarcomas of the extremity, arising in less than 5% of patients. Few studies have evaluated the prognosis and survival of patients with a lymph node metastasis. Early reports compared lymph node involvement to lung metastasis, while others suggested a slightly better outcome. The purpose of this study was to evaluate the impact of lymph node metastasis on patient survival and to investigate the histologic and clinical features associated with lymph node involvement. A retrospective review was done of the prospectively collected soft tissue sarcoma database at our institution. Two thousand forty-five patients had surgery for soft tissue sarcoma of an extremity between January 1986 and August 2017. Included patients either presented with a synchronous lymph node metastasis or were diagnosed with a lymph node metastasis after their initial treatment. Demographic, treatment, and outcome data for patients with lymph node involvement were obtained from the clinical and radiographic records. Lymph node metastases were identified as palpable adenopathy by physical examination and were further characterized on cross-sectional imaging by computed tomography (CT) or magnetic resonance imaging (MRI) scans. All cases were confirmed by pathologic examination of biopsy specimens. A pathologist with expertise in sarcoma determined the histologic type and graded tumors as 1, 2, or 3. One hundred eighteen patients with a mean age of 55.7 (SD=18.9) were included in our study. Seventy-two (61.3%) out of 119 patients were male. Thirty six patients (57.1%) had lymph node involvement at diagnosis. The mean follow-up from the date of the first surgery was 56.3 months. The most common histological diagnoses were Malignant fibrous histiocytoma (35) and liposarcoma (12). Ninety eight patients (89%) underwent surgical treatment of the lymph node metastasis while 21 (17.6%) were treated with chemotherapy and/or radiation therapy. The mean survival was 52.6 months (range 1–307). Our results suggest that patients with a lymph node metastasis have a better prognosis than previously described. Their overall survival is superior to patients diagnosed with lung metastasis. A signifant proportion of patients may expect long term survival after surgical excision of lymph node metastasis. Furthermore, our study also indicates that different histological subtypes such as liposarcoma or malignant peripheral nerve sheath tumor (MPNST) may also be responsible for lymph node metastasis. Additional studies to further improve the treatment of soft tissue sarcoma nodal metastasis are warranted

Aim. The aim of this study was to compare outcomes between patients with diabetic foot soft-tissue infection and osteomyelitis. Methods. Medical records of patients with diabetic foot infection involving either soft-tissue (STI) or bone (OM) were retrospectively reviewed. Diagnosis was determined by bone culture, bone histopathology or imaging with magnetic resonance imaging (MRI) or single-photon emission computed tomography (SPECT/CT). Patient outcomes were recorded up to 1 year after admission. Results. Out of 294 patients included in the study, 137 were diagnosed with STI and 157 had OM. No differences in age (p=.40), sex (p=.79), race (p=.83), body-mass index (p=.79) or type of diabetes (p=.77) were appreciated between groups. Frequency of comorbidities (neuropathy, chronic kidney disease, peripheral arterial disease) also did not differ except for increased prevalence of cardiac disease in patients with STI (86.9%) compared to those with OM (31.8%) (p<.00001) and decreased prevalence of retinopathy (24.8% vs. 35.7%) (p=.04). Patients with OM had greater C-reactive protein (p<.00001), erythrocyte sedimentation rate (p<.00001) and white blood cell count (p<.00001). Among 1-year outcomes, patients with OM more often underwent surgery (p<.00001), had lower limb amputations (p<.00001), became reinfected (p=.0007), were readmitted for the initial problem (p=.008), had longer time to healing (p=.03) and had longer hospital length of stay (p=.00002). However, no differences in 1-year mortality (p=1.000), overall 1-year readmission (p=.06) or healing within 1-year (p=.64) were appreciated. Conclusion. In our study, OM was associated with more aggressive treatment, reinfection and longer time to healing than STI. However, despite being associated with more aggressive care and readmissions, patients with diabetic foot OM has similar 1-year mortality and healing rates to those with diabetic foot STI

Aims. Metal-on-metal total hip replacements (MoM THRs) are frequently revised. However, there is a paucity of data on clinical outcomes following revision surgery in this cohort. We report on outcomes from the largest consecutive series of revisions from MoM THRs and consider pre-revision factors which were prognostic for functional outcome. Materials and Methods. A single-centre consecutive series of revisions from MoM THRs performed during 2006–2015 was identified through a prospectively maintained, purpose-built joint registry. The cohort was subsequently divided by the presence or absence of symptoms prior to revision. The primary outcome was functional outcome (Oxford Hip Score (OHS)). Secondary outcomes were complication data, pre- and post-revision serum metal ions and modified Oxford classification of pre-revision magnetic resonance imaging (MRI). In addition, the study data along with demographic data was interrogated for prognostic factors informing on post-revision functional outcome. Results. 180 revisions in 163 patients were identified at a median follow-up of 5.48 (2–11.7) years. There were 152 (84.4%) in the symptomatic subgroup and 28 (15.6%) in the asymptomatic group. Overall median OHS improved from 29 to 37 with revision (P<0.001). Symptomatic patients experienced greater functional benefit (DOHS 6.5 vs. 1.4, p=0.012) compared to asymptomatic patients, though they continued to report inferior outcomes (OHS 36.5 vs 43, p=0.004). The functional outcome of asymptomatic patients was unaffected by revision surgery (pre-revision OHS 41, post-revision OHS 43, p=0.4). Linear regression analysis confirmed use of a cobalt-chrome (CoCr)-containing bearing surface (MoM or metal-on- polyethylene) at revision and increasing BMI were predictive of poor functional outcome (R. 2. 0.032, p=0.0224 and R. 2. 0.039, p=0.015 respectively). Pre- and post-revision serum metal ions and pre-revision MRI findings were not predictive of outcome. The overall complication rate was 36% (n=65) with a re-revision rate of 6.7%. The most common complication was ongoing adverse reaction to metal debris (ARMD, defined as positive post-revision MRI) in 21.1%. The incidence of ongoing ARMD was not significantly different between those with CoCr reimplanted and those without (p=0.12). Conclusions. To our knowledge, our study represents the largest single-centre consecutive series of revision THRs from MoM bearings in the literature. Symptomatic patients experience the greatest functional benefit from revision surgery but do not regain the same level of function as patients who were asymptomatic prior to revision. The re-implantation of CoCr as a primary bearing surface and increasing BMI was associated with poorer functional outcome

Osteonecrosis (ON) is a debilitating condition that can progress to severe arthritis of the hip. While its exact pathogenesis remains poorly understood, ON is known to be associated with risk factors such as corticosteroid use, alcoholism, and autoimmune disease. Initial radiographic evaluation can reveal sclerotic and cystic changes in the femoral head, which are usually the first clues in diagnosis. Despite these indicators, plain radiographs generally are not sufficient for diagnosis, therefore requiring subsequent magnetic resonance imaging (MRI) studies. Moreover, performing an appropriate assessment of these imaging modalities can help guide the course of treatment. Treatment options are aimed at slowing or stopping the onset of femoral head collapse and include non-operative management, joint preservation procedures, and total joint arthroplasty. Patients at risk of developing ON may benefit from early diagnosis because the characteristic small or medium-sized pre-collapse lesions that are associated with this stage can often be treated with a non-operative or joint preservation approach. However, patients typically present with advanced disease progression and sometimes an unsalvageable joint, thereby necessitating more invasive operative intervention. Surgical modalities include the use of osteotomy, core decompression, vascular grafts, bone graft substitutes, resurfacing, and finally, total hip arthroplasty. Additionally, reports from the past several decades describe improved outcomes and survivorship of these surgical treatment options. Therefore, our purpose is to highlight recent evidence regarding the management of ON with emphasis on the various forms of operative intervention as well as their outcomes

Introduction. Fifteen percent of the primary total knee arthroplasties (TKA) fails within 20 years. Among the main causes for revision surgery are instability and patellofemoral pain. Currently, the diagnostic pathway requires various diagnostic techniques to reveal the original cause for the failed knee prosthesis and is therefore time consuming and inefficient. Accordingly, there is a growing demand for a diagnostic tool that is able to simultaneously visualize soft tissue structures, bone and TKA. Magnetic resonance imaging (MRI) is capable of visualising all the structures in the knee although a trade- off needs to be made between metal artefact reducing capacities and image quality. Low-field MRI (0.25T) results in less metal artefacts and a lower image quality compared with high-field MRI (1.5T). The aim of this study is to develop a MRI imaging guide to image the problematic TKA and to evaluate this guide by comparing low-field and high-field MRI on a case study. Method. Based on literature and current differential diagnostic pathways a guide to diagnose patellofemoral pain, instability, malposition and signs of infection or fracture with MRI was developed. Therefore, methods as Insall Salvati, patellar tilt angle and visibility of fluid and soft tissues were chosen. Visibility was scored on a VAS scale from 0 to 100mm (0mm zero visibility, 100mm excellent visibility). Subsequently, this guide is used to analyse MRI scans made of a volunteer (female, 61 years, right knee) with primary TKA (Biomet, Zimmer) in sagittal, coronal and transversal direction with a FSE PD metal artefact reducing (MAR) sequence (TE/TR 12/1030ms, slice thickness 4.0mm, FOV 260×260×120mm. 3. , matrix size 224×216) on low-field MRI (Esaote G-scan Brio, 0.25T) and with a FSE T. 1. -weighted high bandwidth MAR sequence (TE/TR 6/500ms, slice thickness 3.0mm, FOV 195×195×100mm. 3. , matrix size 320×224) on high-field MRI (Avanto 1.5T, Siemens). Scans were analysed three times by one observer and the intra observer reliability was calculated with a two-way random effects model intra class correlation coefficient (ICC). Results. Due to less metal artefacts on the low-field MRI scans the angle, distance and ratio measurements were more consistent: Insall Salvati low-field 0.97–0.99, Insall Salvati high-field 1.05–1.12, patellar tilt angle low-field 2.1–2.8°, patellar tilt angle high-field 2.4–7.6°. Over all, the VAS scores are higher on the high-field MRI scans; VAS medial collateral ligament high-field 26–45, VAS medial collateral ligament low-field 24–34, VAS popliteus tendon high-field 15–27, VAS popliteus tendon low-field 2–7. The ICC values of the VAS scores, angle measurements and ratio measurements were excellent, ICC > 0.9. The ICC values of the distance measurements were moderate, ICC > 0.6. Conclusion. MRI offers possibilities to simultaneously differentiate underlying causes of the failed knee prosthesis. The structures of interest were more clearly visible on the high-field MRI scans due to higher image contrast. The angle, distance and ratio measurements were more consistent on the low-field MRI scans due to less metal artefacts. Further research should focus on a larger group of patients with complaints after TKA to verify the analysis methods

Patient specific instruments have been developed in response to the conundrum of limited accuracy of intramedullary and extramedullary alignment guides and chaos caused by computer assisted orthopaedic surgery. This technology facilitates preoperative planning by providing the surgeon with a three dimensional (3-D) anatomical reconstruction of the knee, thereby improving the surgeon's understanding of the preoperative pathology. Intramedullary canal penetration of the femur and tibia is unnecessary, and consequently, any potential for fat emboli is eliminated. Component position and alignment are improved with a decrease in the number of outliers. Patient specific instruments utilise detailed magnetic resonance imaging (MRI) or computed tomography (CT) scans of the patient's knee with additional images from the hip and ankle for determination of critical landmarks. From these studies a 3-D model of the patient's knee is created and with integration of rapid prototyping technology, guides are created to apply to the patient's native anatomy to direct the placement of the cutting jigs and ultimately the placement of the components. The steps in considering utilization of patient specific guides are as follows: 1) the surgeon determines that the patient is a candidate for TKA, 2) an MRI or CT scan is obtained at an approved facility in accordance with a specific protocol, 3) the MRI or CT is forwarded to the manufacturer, 4) the manufacturer creates the 3-D reconstructions, anatomical landmarks are identified, implant size is determined, and ultimately femoral and tibial component implant placement is determined via an algorithm, 4) the surgical plan is executed, 5) the physician reviews and modifies or approves the plan, 6) the guides are then produced via rapid prototyping technology and delivered to the hospital for the surgical procedure. Guides generated from MRIs are designed to uniquely register on cartilage surface whereas guides produced from CT scans must register on bony anatomy. There are currently two types of guides produced: those which register on the femur and tibia and allow for the placement of pins to accommodate the standard resection blocks; and those produced by some manufacturers which accommodate the saw blade and therefore are a combination of resection and pin guides. The utilization of patient-specific positioning guides in TKA has several benefits. They facilitate preoperative planning, obviate the need for violation of the intramedullary canals, reduce operating times and improve OR efficiency, decrease instrumentation requirements and thereby reduce potential for perioperative contamination. They are easier to use than computer navigation with no capital equipment purchase and no significant learning curve. Most importantly, patient-specific guides facilitate accurate component position and alignment, which ultimately has been shown to enhance long-term survivorship in total knee arthroplasty

The traditional treatment for a primary anterior shoulder dislocation has been immobilisation in a sling with the arm in adduction and internal rotation. The recurrence rates after the initial traumatic event range from 20% to 94%. However, recent results have suggested that recurrent instability after primary shoulder dislocation may be reduced with immobilisation in external rotation. Since then, controversy exists regarding the position of immobilisation following these injuries. The objective of the present study was to compare immobilisation in internal and external rotation after a primary anterior shoulder dislocation. Fifty patients presenting to our fracture clinic with a primary traumatic anterior dislocation of the shoulder were randomly assigned to treatment with immobilisation in either internal rotation (IR; 25 patients) or external rotation (ER; 25 patients) for three weeks. In addition of a two-years clinical follow-up, patients underwent a magnetic resonance imaging (MRI) of the shoulder with intra-articular contrast within four days following the traumatic event, and then at three months of follow-up. The primary outcome was a recurrent dislocation within 24 months of follow-up. The secondary outcome was the healing rate of the labral lesion seen on MRI (if present) within each immobilisation group. The follow-up rate after two years was 92% (23 of 25) in the IR group and 96% (24 of 25) in the ER group. The recurrence rate in the IR group (11 of 23; 47.8%) was higher than that in the ER group (7 of 24; 29.2%) but the difference did not reach statistical significance (p=0.188). However, in the subgroup of patients aged 20–40 years, the recurrence rate was significantly lower in the ER group (3 of 17; 6.4%) than that in the IR group (9 of 18; 50%, p<0,01). In the subgroup of patients with a labral lesion present on the initial MRI, the healing rate of the lesion was 46.2% (6 of 13) in the IR group and 60% (6 of 10) in the ER group (p=0.680). Overall, the recurrence rate among those who showed healing of the labrum (regardless of the immobilisation group) was 8.3% (1 of 12), but patients who did not healed their labrum had a recurrence rate of 45.5% (5 of 11; p=0.069). This study suggests that immobilisation in ER reduces the risk of recurrence after a primary anterior shoulder dislocation in patients aged between 20 and 40 years. At two years follow-up, the recurrence rate is lower in patients who demonstrated a healed labrum at three months, regardless of the position of immobilisation. Future studies are required in order to identify factors that can improve healing of the damaged labrum following a traumatic dislocation of the shoulder

Magnetic resonance imaging (MRI) scans are widely used in the assessment of knees, often prior to arthroscopic procedures. The reporting of chondral damage on MRI scans can be variable. The correlation between MRI reports of chondral damage and that found at arthroscopy is often inconsistent. The aim of this study was to identify how well MRI reports correlated with the extent of chondral damage found at arthroscopy. A retrospective case-note review of a single-surgeon series of 175 arthroscopic procedures was performed. 83 patients were included in the study. The remainder were excluded if an MRI scan had not been performed, or had been performed more than 3 months prior to surgery. The condition of the articular cartilage demonstrated by MRI was compared to that found at arthroscopy. Data was analysed for presence and extent of chondral damage. Comparison between MRI and arthroscopy findings showed high Specificity (90%) and Negative Predictive Values (89%) for chondral damage, but low Sensitivity (46%). Cohen's kappa values < 0.2 revealed very poor correlation for the extent of damage. This study demonstrates that MRI is good at describing whether articular damage is present but does not reliably describe the extent of the damage