Metabolic and molecular imaging in inflammatory arthritis.

It is known that metabolic shifts and tissue remodelling precede the development of visible inflammation and structural organ damage in inflammatory rheumatic diseases such as the inflammatory arthritides. As such, visualising and measuring metabolic tissue activity could be useful to identify biomarkers of disease activity already in a very early phase. Recent advances in imaging have led to the development of so-called 'metabolic imaging' tools that can detect these changes in metabolism in an increasingly accurate manner and non-invasively.Nuclear imaging techniques such as 18F-D-glucose and fibroblast activation protein inhibitor-labelled positron emission tomography are increasingly used and have yielded impressing results in the visualisation (including whole-body staging) of inflammatory changes in both early and established arthritis. Furthermore, optical imaging-based bedside techniques such as multispectral optoacoustic tomography and fluorescence optical imaging are advancing our understanding of arthritis by identifying intra-articular metabolic changes that correlate with the onset of inflammation with high precision and without the need of ionising radiation.Metabolic imaging holds great potential for improving the management of patients with inflammatory arthritis by contributing to early disease interception and improving diagnostic accuracy, thereby paving the way for a more personalised approach to therapy strategies including preventive strategies. In this narrative review, we discuss state-of-the-art metabolic imaging methods used in the assessment of arthritis and inflammation, and we advocate for more extensive research endeavours to elucidate their full field of application in rheumatology.

The Role of Supramalleolar Osteotomies in Ankle Arthritis.

The supramalleolar osteotomy (SMO) is a joint-preserving surgical procedure that allows realignment of the ankle joint in severe deformity secondary to arthritis. This osteotomy realigns the mechanical axis to provide better weight distribution through the ankle joint. With an aligned mechanical axis, the overloaded asymmetric ankle joint will shift toward the preserved joint area in a valgus or varus ankle joint. The SMO also can be used via a staged approach to correct severe deformity in an end-stage arthritic ankle before total ankle arthroplasty to optimize the implant's longevity and improve overall functional outcomes.

Percutaneous fixation of displaced intraarticular fractures of the calcaneus. A retrospective case series study and a review of the literature.

PURPOSE: To evaluate the outcome of displaced intraarticular calcaneal fractures (DIACFs) of a case series of patients who were treated with a percutaneous fixation technique. MATERIALS AND METHODS: Eight patients were operated for DIACFs and they were evaluated for the outcome and complications in a mean follow up of 9 months (range: 6 - 12 months). At the last follow up the AOFAS score, the Boehlers' angle and the presence of any complication were noted. The time from injury to surgery was also reported. The correlation of the AOFAS score and the development of post traumatic subtalar arthritis to the type of fracture, to the post operative Boehler's angle and to the time from injury to surgery were investigated. RESULTS: The overall mean AOFAS (Americal Orthopaedic Foot and Ankle Society) score was 84,625 (Range: 73 - 96). The mean AOFAS score of type II and type III fractures was 87,667 and 75,500 respectively. The mean AOFAS score for fractures with a postoperative Boehler's angle of less than 10° and more or equal to 10° was 76,750 and 92,500 respectively. This difference was found to be statistically significant. The mean AOFAS score for fractures who were treated less or equal to six days and more than six days post injury was 91,250 and 78 respectively. Two out of four patients with a post operative Boehler's angle less than 10° developed post traumatic subtalar arthritis. No patient out of four for whom a Boehler's angle of more than 10° has been achieved, developed subtalar arthritis. No infection occurred in any of the patients. CONCLUSION: Percutaneous fixation is a safe and effective way of treating DIACFs. The outcome is directly related to the quality of reduction, which is significantly dependent to the timing of surgery. The earlier the fracture is operated the better the reduction by closed means is.

Quantitative 3-D CT Demonstrates Distal Row Pronation and Translation and Radiolunate Arthritis in the SNAC Wrist.

BACKGROUND: In scaphoid nonunion advanced collapse (SNAC) wrist arthritis, we analyzed the 3-dimensional (3-D) deformity patterns of carpal alignment secondary to scaphoid nonunion and quantified subchondral arthritis by investigating alterations in bone density. METHODS: We constructed 3-D models of the carpal bones and radius from 51 patients with scaphoid nonunion (nonunion group) and 50 healthy controls (control group). We quantified the differences in 3-D geometric position of the distal carpal row relative to the distal radius in SNAC wrists versus controls. In addition, we assessed the bone density of anatomic regions of interest in the radiocarpal and capitolunate joints relative to the pisiform bone density to characterize degenerative changes in SNAC wrists. RESULTS: The distal carpal row pronated by a difference of 14° (7.2° versus -6.7°; p < 0.001), deviated ulnarly by a difference of 19° (7.7° versus -11.2°; p < 0.001), shifted dorsally by a difference of 17% of the dorsovolar width of the distal radius (21.0% versus 4.4%; p < 0.001), shifted radially by a difference of 8% of the radioulnar width of the distal radius (13.2% versus 5.3%; p < 0.001), and migrated proximally by a difference of 12% of the lunate height (96.3% versus 108.8%; p < 0.001) in the nonunion group compared with the control group. Additionally, it was found that bone density was greater at the capitolunate joint (capitate head: 140.4% versus 123.7%; p < 0.001; distal lunate: 159.9% versus 146.3%; p < 0.001), the radial styloid (157.0% versus 136.3%; p < 0.001), and the radiolunate joint (proximal lunate: 134.8% versus 122.7%; p < 0.001; lunate fossa: 158.6% versus 148.1%; p = 0.005) in the nonunion group compared with the control group. CONCLUSIONS: Scaphoid nonunion exhibited a unique deformity pattern and alteration in bone-density distributions. The distal carpal row not only shifted dorsally and migrated proximally but also pronated, deviated ulnarly, and shifted radially. Bone density was greater at the capitolunate joint, the radial styloid, and surprisingly, the radiolunate joint. Our findings give insight into the natural history and progression of arthritis of the SNAC wrist. Additionally, future studies may give insight into whether successful treatment of scaphoid nonunion arrests the progression of arthritis. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Best practices for ultrasound-guided synovial biopsy in the United States.

The target organ in many forms of inflammatory arthritis is the synovium. However, synovial tissue has historically been perceived as either difficult to obtain or of little practical value. Ultrasound-guided synovial biopsy [UGSB] is a safe and well-tolerated bedside procedure that is established in Europe and rapidly growing in popularity in the United States. The technique can be mastered by rheumatologists who are already experienced in ultrasound-guided procedures such as joint aspirations. The USGB procedure allows the proceduralist to access small, medium, and large joints and is inexpensive and less invasive compared to surgical alternatives. The relative ease of obtaining this tissue, along with recent research suggesting that synovium may have more clinical and investigational utility than previously thought, has led clinicians and researchers to a new appreciation of the role of synovial biopsy in both the clinical and research setting. In this manuscript, the authors present recommendations on best practices for ultrasound-guided synovial biopsy in the United States, based on our initial training with well-established experts overseas and our own subsequent collective experience in performing numerous synovial biopsies in the United States over the past 7 years for both clinical and research indications. We envision a future where UGSB is more frequently incorporated in the standard diagnostic workup of arthritis and drives novel research initiatives.

Proximal Interphalangeal Joint Arthrodesis of the Hand Utilising a Rigid Intramedullary Device.

The proximal interphalangeal joint (PIPJ) is critical for proper finger and hand function. Arthritis of this joint can lead to significant pain and functional impairment. The APEX IP® Extremity Medical fusion device (Extremity Medical, Parsippany, New Jersey, USA) is an interlocking intramedullary screw device that provides a reliable method of hand PIPJ arthrodesis with good patient outcomes. We describe an easily reproducible surgical technique guide for using this device. Level of Evidence: Level V (Therapeutic).

Change in Height Following Tibiotalocalcaneal Arthrodesis: Retrospective Radiographic Analysis.

Tibiotalocalcaneal arthrodesis (TTCA) with an intramedullary rod is a viable treatment option for a myriad of pathologies involving the foot and ankle. While the current literature has focused on fixation techniques, deformity correction, and clinical outcomes, we are unaware of any studies specifically examining change in height following a TTCA. In the present study, we retrospectively analyzed radiographs with novel radiographic techniques to determine the change in height from preoperative to postoperative radiographs following TTCA. Patients were divided into 3 categories: Charcot, arthritis, and pes planus as the indication for surgical intervention. We found that Charcot and arthritis had an average decrease in height on anterior and posterior measurements of the height from the distal tibia to the calcaneus, while pes planus had an increase in height. The average Charcot change in height was -12.0 ± 24.4 mm anteriorly and -7.6 ± 15.5 mm posteriorly. The average change in height for the arthritis group was -6.9 ± 6.7 mm anteriorly and -3.8 ± 5.8 mm posteriorly. The pes planus group was found to have an average increase in height 0.5 ± 8.0 mm anteriorly and 2.9 ± 5.8 mm posteriorly. Overall, we found a statistically significant difference in height change between the 3 groups in anterior measurements (p = .012) and posterior measurement (p = .006). We recommend surgeons who perform this procedure to be aware of the potential change in height to better tailor surgical and postoperative care.

Lower limb alignment in patients with primary valgus ankle arthritis: A comparative analysis with patients with varus ankle arthritis and healthy controls.

BACKGROUND: While it is commonly acknowledged that the combined effect of lower limb orientation and ankle and hindfoot alignment play a fundamental role in ankle arthritis, supramalleolar/lower limb alignment has received less attention in valgus ankle arthritis. The purpose of this study was to analyze the lower limb alignment of patients with valgus ankle arthritis with primary origin, compared to that of varus ankle arthritis and normal controls. We hypothesized that patients with valgus ankle arthritis would have the opposite pattern of lower limb alignment as those with varus ankle arthritis. METHODS: A retrospective radiographic analysis was performed on 61 patients (62 ankles, mean age, 59.3 ± 12 years) with primary valgus ankle arthritis. On preoperative radiographs, seven parameters, including talar tilt angle, medial distal tibial angle (MDTA), talar center migration, anterior distal tibial angle, talo-first metatarsal (Meary's) angle, hindfoot moment arm (HMA), and mechanical axis deviation (MAD), were measured and compared to those of primary varus ankle arthritis (n = 55; mean age, 59.7 ± 8.1 years) and control patients (n = 59; mean age, 29.3 ± 7.3 years). RESULTS: The valgus group had a significantly lower mean MDTA than the control group (p < 0.0001), indicating a varus distal tibial plafond in comparison to the control group. Meary's angle and HMA were significantly lower in the valgus group compared to the varus group (p < 0.05 and p < 0.0001, respectively), indicating a lower medial longitudinal arch and valgus hindfoot alignment. On whole limb radiographs, the valgus group showed a greater MAD than the control group, indicating varus lower limb alignment (p < 0.05). However, the MAD did not differ significantly between the valgus and varus groups (p = 0.7031). CONCLUSION: Our findings indicate that a significant proportion of ankles with primary valgus arthritis have a varus tibial plafond and a varus lower limb mechanical axis. This study contributes to our understanding of primary valgus ankle arthritis and suggests that lower limb alignment should be analyzed and considered throughout valgus ankle arthritis realignment procedures.

Interobserver and Intraobserver Reliability of Classification Systems for Radiographic Complications After Radial Head Arthroplasty.

PURPOSE: Although several classifications are used to assess radiographs following radial head arthroplasty (RHA), including the Popovic classification for radiolucency, the Chanlalit classification for stress shielding (SS), the Brooker classification for heterotopic ossification (HO), and the Broberg-Morrey classification for radiocapitellar arthritis, little is known about the reliability of these classification systems. The purpose of this study was to determine the interobserver and intraobserver reliability of these classifications. METHODS: Six orthopedic surgeons at various levels of training reviewed elbow radiographs of 20 patients who underwent RHA and classified them according to the Popovic, Chanlalit, Brooker, and Broberg-Morrey classifications for radiolucency, SS, HO, and RHA, respectively. Four weeks after initial review, radiographic reviews were repeated. Reliability was measured using the Fleiss kappa and the intraclass correlation coefficient. Agreement was interpreted as none (<0), slight (0.01-0.2), fair (0.21-0.4), moderate (0.41-0.6), substantial (0.61-0.8), and almost perfect (0.81-1) based on agreement among attending surgeons. RESULTS: Among fellowship-trained attending surgeons, interobserver reliability was slight for SS (Chanlalit) and the categorical interpretation of radiolucency (Popovic), fair for radiocapitellar arthritis (Broberg-Morrey) and HO (Brooker), and substantial for the ordinal interpretation of radiolucency (Popovic). Residents had a higher interobserver reliability than attending physicians when using the Brooker classification. Mean intraobserver reliability was fair for SS (Chanlalit) and the categorical interpretation of radiolucency (Popovic), moderate for HO (Brooker) and radiocapitellar arthritis (Broberg-Morrey), and almost perfect for the ordinal interpretation of radiolucency (Popovic). Trainees had higher intraobserver reliability than attending surgeons using the SS (Chanlalit) classification. CONCLUSIONS: The number of Popovic zones is reliable for communication between physicians, but caution should be taken with the Brooker, Chanlalit, Broberg-Morrey, and categorical interpretation of the Popovic classifications. All the classifications had better intraobserver than interobserver reliability. CLINICAL RELEVANCE: Reliability of classification systems for radiographic complications after RHA is less than substantial except the number of zones of radiolucency; therefore, caution is required when drawing conclusions based on these classifications.

A Systematic Approach to Diagnosing Arthritis Based on Radiological Imaging.

Radiology plays a key role in the diagnosis of arthritis. We herein suggest an algorithmic approach to diagnosing arthritis. First, the number of joint involvements is reviewed. Monoarticular arthritis includes septic arthritis, pigmented villonodular synovitis, and synovial chondromatosis. Second, polyarticular arthritis can be categorized by its characteristics: erosive, productive, and mixed. Erosive disease includes rheumatoid arthritis, hemophilia, and amyloidosis, while productive disease includes osteoarthritis and hemochromatosis. Third, mixed diseases are subcategorized by symmetricity. Ankylosing spondylitis and inflammatory bowel disease related arthritis affect joints symmetrically, while psoriatic arthritis, reactive arthritis, and crystalline arthropathy are asymmetric. Adjacent soft tissue density, periostitis, and bone density are ancillary findings that can be used as additional differential diagnostic clues. The final step in identifying the type of arthritis is to check whether the location is a site frequently affected by one particular disease over another. This systematic approach would be helpful for radiologists in diagnosing arthritis.

Thumb basal joint arthritis: New classification, diagnostic and therapeutic algorithm.

The assessment of thumb basal joint arthritis requires a radiographic evaluation and a classification of the lesions to guide the treatment choice. Arthritis of the thumb basal joint is not limited to trapeziometacarpal arthritis. The radiographic assessment must consider the scaphotrapeziotrapezoid joint, the entire carpus and the rest of the thumb column, in particular the metacarpophalangeal joint. There is currently no classification that captures all these items. This article reviews the existing classifications, proposes a new classification system that takes into account the entire thumb column and sets out the therapeutic options.

Repositional Subtalar Arthrodesis Combined With Supramalleolar Osteotomy for Late-Stage Varus Ankle Arthritis With Hindfoot Valgus.

BACKGROUND: Late-stage varus ankle arthritis is thought to be associated with varus of the tibial plafond and hindfoot. However, some late-stage varus arthritis show hindfoot valgus, which can be explained by subtalar subluxation with opposite directional motion between the talus and calcaneus. We hypothesized that late-stage varus ankle arthritis with hindfoot valgus could improve with repositional subtalar arthrodesis and supramalleolar osteotomy (SMO). The purpose of this study was to investigate the clinical and radiographic results of the repositional subtalar arthrodesis combined with SMO for late-stage varus ankle arthritis with hindfoot valgus. METHODS: This study includes 16 consecutive patients (16 ankles) with late-stage varus ankle arthritis of Takakura stage 3-b and hindfoot valgus who were treated using repositional subtalar arthrodesis combined with SMO and followed for a minimum of 2 years. Clinical results were assessed with the visual analog scale (VAS) and the Foot Function Index (FFI). Radiographic results were assessed with standard parameters measured on weightbearing foot and ankle radiographs. Clinical and radiographic results were evaluated preoperatively and at the last follow-up. RESULTS: VAS and FFI significantly improved after surgery. Mean talar tilt angle improved from 12.8 ± 2.8 degrees to 3.9 ± 3.1 degrees (P < .001). Talus center migration and Meary angle significantly improved after surgery. Medial distal tibial angle, lateral talocalcaneal angle, hindfoot moment arm, and talonavicular coverage angle significantly changed after surgery. Radiographic stage improved in 15 ankles (93.8%) after surgery. CONCLUSION: In this series with minimum 2-year follow-up, we found that late-stage (Takakura stage 3-b) varus ankle arthritis with hindfoot valgus clinically and radiographically improved with repositional subtalar arthrodesis combined with SMO. LEVEL OF EVIDENCE: Level IV, prognostic.

Prenatal cadmium exposure does not induce greater incidence or earlier onset of autoimmunity in the offspring.

We previously demonstrated that exposure of adult mice to environmental levels of cadmium (Cd) alters immune cell development and function with increases in anti-streptococcal antibody levels, as well as decreases in splenic natural regulatory T cells (nTreg) in the adult female offspring. Based on these data, we hypothesized that prenatal Cd exposure could predispose an individual to developing autoimmunity as adults. To test this hypothesis, the effects of prenatal Cd on the development of autoimmune diabetes and arthritis were investigated. Non-obese diabetic (NOD) mice were exposed to Cd in a manner identical to our previous studies, and the onset of diabetes was assessed in the offspring. Our results showed a similar time-to-onset and severity of disease to historical data, and there were no statistical differences between Cd-exposed and control offspring. Numerous other immune parameters were measured and none of these parameters showed biologically-relevant differences between Cd-exposed and control animals. To test whether prenatal Cd-exposure affected development of autoimmune arthritis, we used SKG mice. While the levels of arthritis were similar between Cd-exposed and control offspring of both sexes, the pathology of arthritis determined by micro-computed tomography (µCT) between Cd-exposed and control animals, showed some statistically different values, especially in the female offspring. However, the differences were small and thus, the biological significance of these changes is open to speculation. Overall, based on the results from two autoimmune models, we conclude that prenatal exposure to Cd did not lead to a measurable propensity to develop autoimmune disease later in life.

Joint Preservation Surgery for Varus Ankle Arthritis with Large Talar Tilt.

BACKGROUND: Varus ankle arthritis with large talar tilt (TT) is a challenging condition when considering joint preservation surgery. Three-dimensional deformity of the talus has been demonstrated with weightbearing computed tomography in varus ankle arthritis with large TT. The aim of this study was to investigate the clinical and radiographic results of posterior tibial tendon (PTT) transfer generally combined with bony realignment for varus ankle arthritis with large TT in nonparalytic ankle arthritis and to determine the indications for PTT transfer. METHODS: This study includes 23 ankles with varus arthritis and TT larger than 7.5 degrees. Patients were categorized into improved (19 ankles) and unimproved (4 ankles) groups according to the postoperative clinical results at the last follow-up. Clinical and radiographic results were compared between the groups. A cut-off point for preoperative TT that indicated a borderline between improved and unimproved groups was determined to suggest the appropriate indication for joint preservation surgery. RESULTS: In the improved group, TT, radiographic stage, Meary angle, and hindfoot alignment significantly improved at 6 months after surgery and were maintained at the last follow-up. In the unimproved group, the radiographic parameters mentioned above did not improve at 6 months after surgery, and TT decreased to 0.8 degrees as radiographic stage had progressed to end-stage arthritis at the last follow-up. In this small series, the cut-off point for predicting failure of surgery was 14.3 degrees of preoperative TT. CONCLUSION: PTT transfer often combined with bony realignment procedures may be a reasonable option for treating painful varus ankle arthritis with TT less than 14 degrees and hindfoot varus. LEVEL OF EVIDENCE: Level IV, case series.

Clinical and Radiographic Results of Ankle Joint Preservation Surgery in Posterior Ankle Arthritis.

BACKGROUND: Little information is available about how to manage ankles with eccentric arthritis in the sagittal plane. This study aimed to report clinical and radiographic outcomes following joint preservation surgery for ankles with eccentric arthritis at the posterior tibiotalar joint and a plantarflexed talus in the sagittal plane, which we named posterior ankle arthritis. METHODS: Ten ankles with posterior ankle arthritis were treated with realignment surgery between 2017 and 2018. Posterior ankle arthritis was defined as having both (1) eccentric narrowing of the joint space at the posterior aspect of the tibiotalar joint on weightbearing lateral radiographs and (2) coronal talar tilt angle less than 4 degrees on weightbearing anteroposterior radiographs. Flatfoot reconstruction with a hindfoot arthrodesis procedure was performed in all patients (subtalar arthrodesis, n = 9; triple arthrodesis, n = 1), and a supramalleolar osteotomy was added in patients with varus distal tibial alignment (n = 6). Pain, functional outcome (foot function index [FFI]), radiographic arthritis stage (stage I to IV), and 9 radiographic parameters, including lateral talar center migration (LTCM), were evaluated on pre- and postoperative weightbearing radiographs. All patients completed a minimum 2-year follow-up. RESULTS: Preoperative radiographic evaluation demonstrated that ankles with posterior arthritis had a lower medial longitudinal arch, forefoot abduction, and valgus hindfoot alignment. Postoperatively, sagittal tibiotalar alignment was restored, as evidenced by an improved median LTCM from -3.3 to -0.3 mm (P < .001). The radiographic arthritis stage improved in 7 (70%) patients, whereas 3 (30%) remain unchanged in the same stage. The median score for pain (visual analog scale) decreased significantly from 8 to 2, and the median FFI improved significantly from 67.8 to 23.4 (P < .001). None of the patients underwent conversion to joint-sacrificing procedures at the latest follow-up. CONCLUSION: The study results suggest a possible relationship between posterior ankle arthritis and the plantarflexion of the talus, which can be seen in the setting of a flatfoot deformity. Reconstruction of the flatfoot deformity using subtalar arthrodesis restored the tibiotalar relationship in the sagittal plane and resulted in clinical improvements at an average 2.3-year follow-up in this 10-ankle case series. LEVEL OF EVIDENCE: Level IV, case series.

Development and ex-vivo assessment of a novel patient specific guide and instrumentation system for minimally invasive total shoulder arthroplasty.

OBJECTIVE: To develop and assess a novel guidance technique and instrumentation system for minimally invasive short-stemmed total shoulder arthroplasty that will help to reduce the complications associated with traditional open replacement such as poor muscle healing and neurovascular injury. We have answered key questions about the developed system including (1) can novel patient-specific guides be accurately registered and used within a minimally invasive environment?; (2) can accuracy similar to traditional techniques be achieved? METHODS: A novel intra-articular patient-specific guide was developed for use with a new minimally invasive posterior surgical approach that guides bone preparation without requiring muscle resection or joint dislocation. Additionally, a novel set of instruments were developed to enable bone preparation within the minimally invasive environment. The full procedure was evaluated in six cadaveric shoulders, using digitizations to assess accuracy of each step. RESULTS: Patient-specific guide registration accuracy in 3D translation was 2.2±1.2mm (RMSE±1 SD; p = 0.007) for the humeral component and 2.7±0.7mm (p<0.001) for the scapula component. Final implantation accuracy was 2.9±3.0mm (p = 0.066) in translation and 5.7-6.8±2.2-4.0° (0.001

A novel apoptosis probe, cyclic ApoPep-1, for in vivo imaging with multimodal applications in chronic inflammatory arthritis.

Apoptosis plays an essential role in the pathophysiologic processes of rheumatoid arthritis. A molecular probe that allows spatiotemporal observation of apoptosis in vitro, in vivo, and ex vivo concomitantly would be useful to monitoring or predicting pathophysiologic stages. In this study we investigated whether cyclic apoptosis-targeting peptide-1 (CApoPep-1) can be used as an apoptosis imaging probe in inflammatory arthritis. We tested the utility of CApoPep-1 for detecting apoptotic immune cells in vitro and ex vivo using flow cytometry and immunofluorescence. The feasibility of visualizing and quantifying apoptosis using this probe was evaluated in a murine collagen-induced arthritis (CIA) model, especially after treatment. CApoPep-1 peptide may successfully replace Annexin V for in vitro and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay for ex vivo in the measurement of apoptotic cells, thus function as a sensitive probe enough to be used clinically. In vivo imaging in CIA mice revealed that CApoPep-1 had 42.9 times higher fluorescence intensity than Annexin V for apoptosis quantification. Furthermore, it may be used as an imaging probe for early detection of apoptotic response in situ after treatment. The CApoPep-1 signal was mostly co-localized with the TUNEL signal (69.6% of TUNEL+ cells) in defined cell populations in joint tissues of CIA mice. These results demonstrate that CApoPep-1 is sufficiently sensitive to be used as an apoptosis imaging probe for multipurpose applications which could detect the same target across in vitro, in vivo, to ex vivo in inflammatory arthritis.

The use of magnetic resonance imaging (MRI) of the knee in current clinical practice: A retrospective evaluation of the MRI reports within a large NHS trust.

BACKGROUND: Magnetic resonance imaging (MRI) is one of the most widely used investigations for knee pain as it provides detailed assessment of the bone and soft tissues. The aim of this study is to report the frequency of each diagnosis identified on MRI scans of the knee and explore the relationship between MRI results and onward treatment. METHODS: Consecutive MRI reports from a large NHS trust performed in 2017 were included in this study. The hospital electronic system was consulted to identify whether a patient underwent x-ray prior to the MRI, attended an outpatient appointment or underwent surgery. RESULTS: 4466 MRI knees were performed in 2017 with 71.2% requested in primary care and 28.1% requested in secondary care. The most common diagnosis was signs of arthritis (55.2%), followed by meniscal tears (42.8%) and ACL tears (8.3%). 49.4% of patients who had an MRI attended outpatients and 15.6% underwent surgery. The rate of knee surgery was significantly higher for patients who had their scans requested in secondary care (32.9% vs 8.9%, p < 0.001). CONCLUSION: The rate of surgical intervention following MRI is low and given these results it seems unlikely that the scan changes practice in most cases. The rate of surgery and outpatient follow up was significantly higher in scans requested by secondary care. We urge clinicians avoid wasteful use of MRI and recommend the use of plain radiography prior to MRI where arthritis may be present.