Introduction: Biodegradable systems releasing antibiotics are promising candidates for the management of chronic osteomyelitis. Gentamicin and fluoroquinolones are the commonest antibiotics applied with these systems. The effectiveness of a new system from polymerized dilactide (PLA) with incorporated linezolid has been investigated in a rabbit model for treating osteomyelitis by methicillin-resistant Staphylococcus Aureus (MRSA).

Methods: The PLA – Linezolid system was made after thorough stirring 2gr of polymer with 100 mg of linezolid. Experimental osteomyelitis was established in 40 rabbits by a modification of the Norden model. Methicillin-resistant Staphylococcus aureus (MRSA) was applied as the test isolate. After drilling a hole in the upper right femur, the isolate was inoculated along with a thin needle working as a foreign body. After three weeks the needle was removed and cultured and PLA-Linezolid system was implanted in half of the animals. Animals were sacrificed at regular time intervals and tissue around the site of implantation was sent for histologic examination and quantitative cultures.

Results: At 2 – 4 – 6 – 8 – 10 weeks time after removal of the needle results (mean values) were as follows (Controls/PLA-Linezolid): Log10 (cfu/g) at infection site: 2.99/5.68 – 3.44/3.20 – 3.22/2.39 – 1.00/1.27 – 1.00/1.00 respectively and Δlog10 (cfu/g) compared to start: −0.05/−3.23 – 0.23/0.13 – 0.05/0.93 – 1.34/1.09 – 3.31/3.34 respectively. Histology confirmed the previous mentioned results, showing an early decrease following by late recurrence of the infectious reaction at the animals that PLA-Linezolid system was used.

Conclusions: It is concluded that the applied system achieved an early decrease of the tissue bacterial load which was not maintained until late on follow-up. This might be explained by the bacteriostatic mode of action of linezolid.

Aims: The evaluation of the results becoming from the use of demineralized bone matrix (DBM) in the bone defects.

Methods: In the present study the above substance was implanted during the period 2000–2002 (28 months) to 24 patients, 11 males and 13 females average age 39.1 for the males and 60 for the females. As a cause was referred in 12 patients the fall, in 3 patients the car crash, in 5 patients following the removal of osteosynthesis materials, in 2 patients the bone cysts, in 1 patient fracture of ankle joint following fusion and in 1 patient a pseudarthrosis. The implantation of DBM concerned 8 hips, 4 femurs, 6 knees, 1 humerus, 1 forearm, 1 ankle, 2 metacarpal and 1 phalanx. All the fractures as well the fusion were treated through internal fixation. There was a regular post op follow-up and concerned the clinical and x-ray examination per month until the total incorporation of the graft (12 weeks).

Results: In all patients the total incorporation of the DBM was accomplished in a brief period of time, depended on the place of implantation without having local or systemic side effects. We have to remark the early signs of bone shadow around the 3rd week, as well the incorporation of the matrix around the 12th week in the x-ray findings.

Conclusions: The use of DBM in bone defects could play an important role to the filling of bone defects due to fractures or benign cysts as a result of its incorporation and without inducing local or systematic side effects.

Purpose: To investigate the accuracy of the MRI of the knee for the detection of injuries of the meniscus, cruciate ligaments and articular cartilage, in comparison with the preoperative clinical examination and intraoperative findings.

Material and methods: During 2002 88 patients underwent surgical arthroscopy in our institution, with the diagnosis of meniscal and or cruciate tear. 56 from these patients had preoperative MRI of the affected knee. The accuracy, sensitivity and specificity of the MRI findings were correlated with the lesions identified during arthroscopy. Furthermore, the predictive value of the preoperative MRI was compared with the preoperative clinical evaluation, as well as definitive intraoperative findings.

Results : The accuracy for tears of the medial, lateral meniscus, anterior and posterior cruciate ligaments and articular cartilage was 81%, 77%, 86%, 98% and 60% respectively. The specificity was 69%, 88%, 89%, 75% and 73% respectively. The positive predictive value was 83%, 81%, 90%, 100% and 53% respectively. Finally, the clinical examination had less reliability in the detection of these injuries.

Conclusions: As seen in this retrospective study the accuracy of the MRI in detecting injuries to the knee is superior to the clinical examination. The arthroscopy still remains the gold standard for definitive diagnosis.