MR arthrography is slightly more accurate than conventional MRI in detecting TFCC lesions of the wrist.

INTRODUCTION: In case of clinical suspicion of triangular fibrocartilage complex (TFCC) injury, different imaging techniques are used. The aim of this study was to determine whether MRA is superior to MRI and whether 3.0 T is better than 1.5 T (expresses in sensitivity, specificity and accuracy) in detecting TFCC injury, using arthroscopy as the gold standard. MATERIALS AND METHODS: The arthroscopic and MR findings of 150 patients who underwent arthroscopy for ulnar-sided wrist pain between January 2009 and November 2016 were retrospectively reviewed. RESULTS: MRA was slightly more accurate compared to conventional MRI, and 1.5 T was slightly more accurate than 3.0 T. 1.5 T wrist MRA had a sensitivity of 80%, a specificity of 100% and accuracy of 90%; 3.0 T wrist MRA 73, 100 and 86%, resp. Conventional 1.5 T wrist MRI had a sensitivity of 71%, a specificity of 75% and accuracy of 73%. For 3.0 T conventional MRI, this was 73, 67 and 70%, resp. CONCLUSIONS: MRA seems slightly superior to conventional MRI, but one could question whether this difference in diagnostic accuracy outweighs the burden and risks of an invasive procedure for patients with its additional costs. Furthermore, we could not confirm the superiority of 3 T compared to 1.5 T.

Low-field magnetic resonance imaging offers potential for measuring tibial component migration.

BACKGROUND: Roentgen stereophotogrammetric analysis (RSA) is used to measure early prosthetic migration and to predict future implant failure. RSA has several disadvantages, such as the need for perioperatively inserted tantalum markers. Therefore, this study evaluates low-field MRI as an alternative to RSA. The use of traditional MRI with prostheses induces disturbing metal artifacts which are reduced by low-field MRI. The purpose of this study is to assess the feasibility to use low-field (0.25 Tesla) MRI for measuring the precision of zero motion. This was assessed by calculating the virtual prosthetic motion of a zero-motion prosthetic reconstruction in multiple scanning sessions. Furthermore, the effects of different registration methods on these virtual motions were tested. RESULTS: The precision of zero motion for low-field MRI was between 0.584 mm and 1.974 mm for translation and 0.884° and 3.774° for rotation. The manual registration method seemed most accurate, with µ ≤ 0.13 mm (σ ≤ 0.931 mm) for translation and µ ≤ 0.15° (σ ≤ 1.63°) for rotation. CONCLUSION: Low-field MRI is not yet as precise as today's golden standard (marker based RSA) as reported in the literature. However, low-field MRI is feasible of measuring the relative position of bone and implant with comparable precision as obtained with marker-free RSA techniques. Of the three registration methods tested, manual registration was most accurate. Before starting clinical validation further research is necessary and should focus on improving scan sequences and registration algorithms.

Survey on the management of acute first-time anterior shoulder dislocation amongst Dutch public hospitals.

INTRODUCTION: The primary aim of this study was to record how orthopaedic surgeons are currently managing acute first-time anterior shoulder dislocation (AFASD) 8 years after introduction of the Dutch national guideline: "acute primary shoulder dislocation, diagnostics and treatment" in 2005. The second aim was to evaluate how these surgeons treat recurrent instability after AFASD. MATERIALS AND METHODS: An online questionnaire regarding the management of AFASD and recurrent shoulder instability was held amongst orthopaedic surgeons of all 98 Dutch hospitals. RESULTS: The overall response rate was 60%. Of the respondents, 75% had a local protocol for managing AFASD, of which 28% had made changes in their treatment protocol after the introduction of the national guideline. The current survey showed wide variety in the overall treatment policies for AFASD. Twenty-seven percent of the orthopaedic surgeons were currently unaware of the national guideline. The variability in treatment for AFASD was present throughout the whole treatment from which policy at the emergency department; when to operate for recurrent instability; type of surgical technique for stabilization and type of fixation of the labrum. As for the treatment of recurrent instability, the same variability was seen: 36% of the surgeons perform only arthroscopic procedures, 7% only open and 57% perform both open and arthroscopic procedures. CONCLUSIONS: Despite the introduction of the national guideline for the initial management of AFASD in 2005, still great variety among orthopaedic surgeons in the Netherlands was present. As for the surgical stabilization technique, the vast majority of the respondents are performing an arthroscopic shoulder stabilization procedure at the expense of the more traditional open procedure as a first treatment option for post-traumatic shoulder instability.

The new proximal femoral nail antirotation (PFNA) in daily practice: results of a multicentre clinical study.

The treatment of unstable trochanteric femoral fractures is still challenging. The ideal implant should be easy to handle, allow for immediate full weight-bearing postoperatively and should have sufficient purchase in the femoral head/neck-fragment to limit cut-outs due to varus-deviation and rotation. The proximal femoral nail antirotation (PFNA), designed by AO, is an intramedullary device with a helical blade rather than a screw for better purchase in the femoral head and was tested in a clinical study. Consecutive patients with unstable trochanteric fractures (AO-classification 31.A.2 and A.3 only) were included and followed for 1 year. Primary objectives were assessment of operative and postoperative complications, whereas secondary objectives included surgical details, general complications and final outcome measurements. In 11 European clinics, 315 patients were included and treated with a PFNA. Almost all fractures healed within 6 months. Fifty-six percent of the patients regained the pre-trauma mobility and 18% died within the follow-up period. Forty-six implant-related complications--leading to 28 unplanned re-operations--were recorded, with four acetabular penetrations (three of which were after a new fall on that hip) and seven ipsilateral femoral shaft fractures as the most serious ones. As the joint-penetrations did not resemble the cut-out seen with other implants it is concluded that the PFNA--due to its helical blade--possibly limits the effects of early rotation of the head/neck-fragment in unstable trochanteric fractures and therefore seems currently to be the optimal implant for the treatment of these fractures especially in osteoporotic bone.