MRI evaluation of the peripheral attachments of the lateral meniscal body: the menisco-tibio-popliteus-fibular complex

PURPOSE

To determine, identify and measure the structures of the menisco-tibio-popliteus-fibular complex (MTPFC) with magnetic resonance imaging (MRI) in knees without structural abnormalities or a history of knee surgery.

METHODS

One-hundred-and-five knees without prior injury or antecedent surgery were analyzed by means of MRI. The average age was 50.1 years ± 14.8. All the measurements were performed by three observers. The peripherical structures of the lateral meniscus body were identified to determine the location, size, and thickness of the entire MTPFC. The distance to other "key areas" in the lateral compartment was also studied and compared by gender and age.

RESULTS

The lateral meniscotibial ligament (LMTL) was found in 97.1% of the MRIs, the popliteofibular ligament (PFL) in 93.3%, the popliteomeniscal ligaments (PML) in 90.4% and the meniscofibular ligament (MFL) in 39%. The anteroposterior distance of the LMTL in an axial view was 20.7 mm ± 3.9, the anterior thickness of the LMTL was 1.1 mm ± 0.3, and the posterior thickness of the LMTL 1.2 mm ± 0.1 and the height in a coronal view was 10.8 mm ± 1.9. The length of the PFL in a coronal view was 8.7 mm ± 2.5, the thickness was 1.4 mm ± 0.4 and the width in an axial view was 7.8 mm ± 2.2.

CONCLUSIONS

The MTPFC has a constant morphological and anatomical pattern for three of its main ligaments and can be easily identified and measured in an MRI; the MFL has a lower prevalence, considering a structure difficult to identify by 1.5 T MRI.

The morphology of the femoral footprint of the anterior cruciate ligament changes with aging from a large semicircular shape to a small flat ribbon-like shape

PURPOSE

Compare the differences in the morphology of the ACL femoral footprint between the cadavers of the young and elderly in consideration of the degenerative physiological process that occurs with aging.

METHODS

The femoral footprint of the ACL was dissected in 81 knees of known gender and age (45 male/36 female). They were divided into four groups by age and gender, establishing 50 years as the cut-off point to divide patients by age. Three observers analyzed the femoral footprint dissections, and the shapes were described and classified. The area and morphometric characteristics of the femoral insertion of the ACL were determined and these were compared between genders and age groups.

RESULTS

The femoral footprint of the ACL from the cadavers of males younger than 50 years of age presented a semicircular morphology in 90% of the cases. In males aged more than 50 years, a ribbon-like morphology was found in 96% of the cases. In women less than 50 years old, the semicircular morphology was observed in 93.7% of the cases. In women aged over 50 years old, the ribbon-like morphology was found in 95% of the cases. A significant difference was observed between the prevalence rates of the morphologies, area size and measurements of the younger and older groups (p < 0.001 for both genders).

CONCLUSIONS

The femoral insertion of the ACL presents variations in its morphology, area and morphometric characteristics over time. It goes from a large semicircular shape that almost contacts the posterior articular cartilage to a smaller, flattened ribbon-like shape that moves away from the edge of the articular cartilage. It is bounded anteriorly by the lateral intercondylar ridge. These findings should be considered to avoid employing reconstruction techniques in which femoral tunnels with oval or rectangular shapes are used in patients under 50 years of age because they do not correspond to the morphology of the femoral insertion of the ACL in this age group.

Dermatology Surgery Training in a Live Animal Model

Background Surgical technique is an important part of resident training, which is the reason why various models have been implemented to acquire this skill. Animal models have been useful in teaching dermatologic suturing techniques. With the advancements in technology, simulators have been developed for these exercises, but at a very high cost. The use of pig heads and freshly killed animals have proven to be effective and low-cost. However, they do not reproduce skin pathologies with accuracy.

Objective To evaluate the effectiveness of a live anesthetized rat model to simulate skin pathologies requiring surgical excision in a dermatologic suture workshop for residents.

Methods We analyze the outcome of a theoretical and practical suturing workshop using live Wistar rats with 13 dermatology residents.

Results The residents showed an improvement in surgical maneuvers, suturing techniques, and in the use of surgical instruments (p < 0.01).

Conclusion The model proposed in the present study was economic, easy to obtain and to manage, and it portrays live and accurate skin response to manipulation. Therefore, it is effective for conducting surgical training sessions in dermatology.

[Efficacy of sedation in outpatient procedures performed by pediatric residents]

OBJECTIVE

To determine the efficacy of sedation in outpatient procedures performed by Pediatric Residents.

MATERIAL AND METHODS

Observational, analytic, cross-sectional study in patients that require diagnostic and therapeutic procedures. Data were collected during the period between June 01 and September 2007 in the Pediatrics Department. Patients from 1 month to 15 years of age that required sedation were included.

RESULTS

97 sedations were carried out, with an average age of 3.5 years. 59.3% were males and 40.7% were females. 100% of the procedures were carried out with 12.3% adverse effects.

CONCLUSIONS

The procedures were done successfully; the pediatric residents demonstrated the required preparation for sedating and reverting adverse effects.