Quantitative T2 mapping seems to reflect differences in repair tissues formed after two surgical cartilage repair procedures. (c) RSNA, 2008.

The results of our study were similar to several previous reports, underscoring a low incidence (1.2%) and age-related characteristics. Younger children had a predilection for injuries of the upper cervical spine, whereas children in the older age group sustained significantly more injuries of the lower cervical spine. Spinal cord injuries without radiographic abnormalities were only seen in the younger age group. Despite the low incidence of cervical spine injuries in pediatric patients, increased efforts at prevention are demanded because mortality rate (27%) and incidence of neurologic deficits (66%) were dreadfully high in our series.

Matrix-induced autologous chondrocyte implantation (MACI) is a tissue-engineering technique for the treatment of full-thickness articular cartilage defects and requires the use of a three-dimensional collagen type I-III membrane seeded with cultured autologous chondrocytes. The cell-scaffold construct is implanted in the debrided cartilage defect and fixed only with fibrin glue, with no periosteal cover or further surgical fixation. In a clinical pilot study, the MACI technique was used for the treatment of full-thickness, weight-bearing chondral defects of the femoral condyle in 16 patients. All patients were followed prospectively and the early postoperative attachment rate, 34.7 days (range: 22-47) after the scaffold implantation, was determined. With the use of high-resolution magnetic resonance imaging (MRI), the transplant was graded as completely attached, partially attached, or detached. In 14 of 16 patients (87.5%), a completely-attached graft was found, and the cartilage defect site was totally covered by the implanted scaffold and repair tissue. In one patient (6.25%), a partial attachment occurred with partial filling of the chondral defect. A complete detachment of the graft was found in one patient (6.25%), which resulted in an empty defect site with exposure of the subchondral bone. Interobserver variability for the MRI grading of the transplants showed substantial agreement (kappa=0.775) and perfect agreement (kappa(w)=0.99). In conclusion, the implantation and fixation of a cell-scaffold construct in a deep cartilage defect of the femoral condyle with fibrin glue and with no further surgical fixation leads to a high attachment rate 34.7 days after the implantation, as determined with high resolution MRI.

No abstract

Penetration of linezolid into bone and joint tissues was studied by high-performance liquid chromatography in 13 patients suffering from implant-associated infections with methicillin-resistant staphylococci. Mean concentrations of linezolid in infected tissues were greater than 10 mg/liter in a sampling time range of 35 to 124 min after administration of the preoperative dose, except in bone specimens, where they reached 3.9 ؎ 2.0 mg/liter.

The purpose was to evaluate the relative glycosaminoglycan (GAG) content of repair tissue in patients after microfracturing (MFX) and matrix-associated autologous chondrocyte transplantation (MACT) of the knee joint with a dGEMRIC technique based on a newly developed short 3D-GRE sequence with two flip angle excitation pulses. Twenty patients treated with MFX or MACT (ten in each group) were enrolled. For comparability, patients from each group were matched by age (MFX: 37.1 +/- 16.3 years; MACT: 37.4 +/- 8.2 years) and postoperative interval (MFX: 33.0 +/- 17.3 months; MACT: 32.0 +/- 17.2 months). The Delta relaxation rate (DeltaR1) for repair tissue and normal hyaline cartilage and the relative DeltaR1 were calculated, and mean values were compared between both groups using an analysis of variance. The mean DeltaR1 for MFX was 1.07 +/- 0.34 versus 0.32 +/- 0.20 at the intact control site, and for MACT, 1.90 +/- 0.49 compared to 0.87 +/- 0.44, which resulted in a relative DeltaR1 of 3.39 for MFX and 2.18 for MACT. The difference between the cartilage repair groups was statistically significant. The new dGEMRIC technique based on dual flip angle excitation pulses showed higher GAG content in patients after MACT compared to MFX at the same postoperative interval and allowed reducing the data acquisition time to 4 min.

No abstract

Surgical treatment of displaced greater tuberosity fractures revealed good functional and radiographic results. Reduction and fixation of those fractures is recommended because patients with nonoperative treatment showed significantly worse results. Similar results can be achieved for open reduction and internal fixation, or closed reduction and percutaneous fixation.