Nobuhiro Tanaka

A rare case of absence of the celiac trunk: the left gastric, the splenic, the common hepatic and the superior mesenteric arteries arising independently from the abdominal aorta

This report describes a rare case of absence of the celiac trunk, which was encountered in a Japanese female cadaver in the dissecting room at Kurume University School of Medicine in 1993. In this case, the left gastric, the splenic, the common hepatic and the superior mesenteric arteries arose independently in that order from the abdominal aorta. In addition, the left aberrant hepatic artery arose from the left gastric artery. This anomalous case belongs to type 5 (Typus primitivus) of Moritas classification (1935), and is the fifth case of this kind of vascular variation to be reported in Japan.

Analysis of strain distribution in the medial collateral ligament using a photoelastic coating method

The strain distribution over the entire medial collateral ligament (MCL) was measured using a photoelastic coating method. This new approach utilized a polyurethane monomer as a photoelastic coating film. The initial experiments investigating MCL strain measurement showed that this film had a high sensitivity for strain and good adhesion to the ligament. It was confirmed that strain distribution could be obtained qualitatively over the entire ligament using this method. The mechanism of MCL injury was studied by applying this polyurethane coating film to the entire MCL in a femur-MCL-tibia complex. When simple tension was applied to the complex, strain concentrations were centred at the tibial insertion site, and all the specimens ruptured at the MCL tibial insertion site. With application of a valgus bending moment, increased strain was seen in the MCL from the medial femoral condyle to the medial epicondyle. Histological analysis demonstrated midsubstance ligament ruptures in this same region. For both tests, rupture sites and increased strain concentration sites correlated. In addition, an impingement phenomenon of the MCL on the medial femoral condyle can be seen during application of valgus force, and this phenomenon may explain the higher incidence of MCL injuries on the femoral side seen in the clinical setting. This polyurethane coating method allows for direct and visual measurements, and can qualitatively measure the strain behaviour over the entire MCL surface. This new technique represents a significant improvement over previous point-by-point strain measurement methods.

Deterioration of the femoral articular surface after meniscal repair evaluated by second-look arthroscopy: comparison with partial meniscectomy

Abstract To evaluate whether meniscal repair can protect the cartilage deterioration, changes in articular cartilage of the involved compartment were evaluated by reviewing the videotapes recorded at the time of operations (33 meniscal repairs, 18 meniscectomies) and second-look arthroscopies. Meniscal repairs gave marginally better results than meniscectomies but the articular cartilage was often deteriorated in cases that had the incompletely healed meniscus or the unhealed meniscus. Although completely healed menisci restore the meniscal function and protect the articular damage, unsuccessful meniscal healings sometimes provoke degeneration of the articular cartilage.

Frequency Analysis of Surface EMG on Knee Extensors in Cases with ACL Insufficiency. Per- and Post-operative Comparison.

Six cases (4 males, 2 females) with ACL insufficiency were evaluated by frequency analysis of surface EMG preoperatively and at 4 or 6 months after surgery. Patients ranged in age from 17 to 41 years (mean 27 years). The surface EMG was recorded from above the quadriceps muscle during sustained (30 sec.) isometric contraction. The recorded EMG was computerized by spectrum analyzer. Results were as follows. Mean power frequency showed a more sudden decrease post-operatively compared to per-operative values. In other words, the higher (>81Hz) frequency zone was increased post-operatively compared with pre-operation. We concluded that type II fibres on knee extensors were actived by reconstrution and rehabilitation.