Diagnostic accuracy of 99mTc-antigranulocyte SPECT/CT in patients with osteomyelitis and orthopaedic device-related infections: A retrospective analysis.

OBJECTIVES: Conventional imaging techniques are routinely used in the diagnostic work-up of patients with suspected osteomyelitis or orthopaedic implant-associated infections. Hybrid nuclear medicine imaging techniques are a suitable alternative to routine imaging modalities as they provide anatomical and functional information within one procedure. Our study investigated the performance of anti-granulocyte SPECT/CT using 99mTc-labelled monoclonal antibodies in the diagnosis of osteomyelitis and orthopaedic implant-associated infections. METHODS: In this retrospective analysis, we included patients with 99mTc-antigranulocyte SPECT/CT acquired in the context of a suspected bone and joint infection. All patients underwent routine diagnostics and/or had a clinical follow-up of at least 12months. RESULTS: 26 episodes were included. Fifteen exams were performed for suspected osteomyelitis, and 11 for suspected orthopaedic implant-associated infection. SPECT/CT was ordered most often if standard diagnostic tests or conventional imaging modalities remained inconclusive. The overall sensitivity and specificity for the diagnosis of an infection were 77.8% and 94.1%, respectively. The positive predictive value was 87.5% and the negative predictive value 88.9%. Diagnostic accuracy was 88.5%. CONCLUSIONS: 99mTc-antigranulocyte SPECT/CT imaging has a high accuracy in the diagnosis of osteomyelitis and orthopaedic implant-associated infections and is a suitable non-invasive diagnostic tool if standard diagnostic examinations are inconclusive or not applicable.

[Complex reconstruction in Charcot arthropathy using the Ilizarov ring fixator]. / Komplexe Rekonstruktionen bei Charcot-Arthropathie mittels Ilizarov-Ringfixateur.

BACKGROUND: From the foot surgeon's point of view, the surgical treatment of Charcot neuro-osteopathy is considered challenging. Conservative treatment using plaster and orthoses is used to treat Charcot arthropathy, especially in the acute stage of a treatment strategy. Surgical treatment using the Ilizarov ring fixator is established for the correction of residual misalignments and also in the acute stage. Advantages of the ring fixator are great stability of the apparatus, low loading of the soft tissues caused by foreign material, and possible long-term treatment. OBJECTIVES: The aim of this work is to explain the indication, planning of correction, assembly of Ilizarov ring fixator, and the postoperative treatment with respect to the literature and the authors' experience. The aim of treatment with the Ilizarov ring fixator is a plantigrade, resilient, ulcer-free foot. Treatment is lengthy for both the affected patients and the attending orthopedic surgeon, and great attention is required to achieve the desired corrections and a good result for the patient. DISCUSSION: According to the literature and the authors' experience, the results indicate that the Ilizarov ring fixator represents a viable method for the preservation of the affected limb in patients with Charcot neuro-osteopathy. The assembly of the apparatus must follow the principles of Ilizarov in order to avoid failure. Corrective osseous and soft tissue interventions require a detailed preoperative analysis.

[Symptomatic treatment of non-displaced avulsion and Jones fractures of the fifth metatarsal: a prospective study]. / Traitement symptomatique des fractures non déplacées de la base du cinquième métatarse: étude prospective.

The objective was to compare the results of a conservative treatment of non-displaced Jones fractures and of avulsion fractures of the fifth metatarsal. In 2004/2005 29 fractures of the fifth metatarsal were distinguished into avulsion fractures (n = 21) and Jones fractures (n =8). Six patients with avulsion fractures were lost. We proposed the same treatment for the two groups: Elastic banding, pain killers, crutches if needed and thromboembolic prophylaxis with low molecular heparin. After twelve weeks none of the patients complained about pain. Radiographic consolidation of the fracture was noticed after 7.3 weeks for the Jone's fractures and after 7.1 weeks for the avulsion fractures. We propose symptomatic treatment for the non-displaced avulsion and Jones fractures.

The risk of injury to neurovascular structures from distal locking screws of the Unreamed Humeral Nail (UHN): a cadaveric study.

When performing distal interlocking of an intramedullary humeral nail, there is risk of iatrogenic injuring to the neurovascular structures. Our cadaveric study with frozen sections through the distal humerus presents the anatomic relationship of the different neurovascular bundles and the trajectories used for the implantation of the three distal interlocking screws of the AO-UHN. The middle lateromedial pin was in direct contact with the radial nerve in 3 out of 10 cases, with the ulnar nerve in 3 out of 10 cases and with the brachial artery in 1 out of 10 cases. We recommend using only the two anteroposterior screws for distal interlocking, avoiding the lateromedial locking option. If this lateromedial locking screw is needed to gain adequate stability, it should be introduced under visual control.

Numerical analysis of the effects of material parameters on the lubrication mechanism for knee prosthesis.

The tibial component of current knee prostheses made of ultra high molecular weight polyethylene (UHMWPE) has a high degree of wear that causes knee inflammation, prosthesis loosening and subsequent replacement in not more than 15 years. In order to know which UHMWPE material properties have more influence on wear, a steady state lubrication model with non-Newtonian synovial fluid has been studied through numerical solution. The results show that UHMWPE has a very high elastic modulus that makes difficult a well lubricated artificial joint and induces the formation of very thin lubricating films between the moving surfaces with the same magnitude of roughness components. This study shows that the use of deformable porous materials in the tibial component could cause the lubricating film thickness to be higher than the average roughness and the pressure levels to be lower than the one predicted for UHMWPE. These two facts imply friction and wear reduction.