Y. Takazawa

The degeneration and destruction of femoral articular cartilage shows a greater degree of deterioration than that of the tibial and patellar articular cartilage in early stage knee osteoarthritis: a cross-sectional study

OBJECTIVE The aim of the present study was to examine whether the degenerative and morphological changes of articular cartilage in early stage knee osteoarthritis (OA) occurred equally for both femoral- and tibial- or patellar- articular cartilage using magnetic resonance imaging (MRI)-based analyses. DESIGN This cross-sectional study was approved by the ethics committee of our university. Fifty patients with early stage painful knee OA were enrolled. The patients underwent 3.0 T MRI on the affected knee joint. Healthy volunteers who did not show MRI-based OA changes were also recruited as controls (n = 19). The degenerative changes of the articular cartilage were quantified by a T2 mapping analysis, and any structural changes were conducted using Whole Organ Magnetic Resonance Imaging Score (WORMS) technique. RESULTS All patients showed MRI-detected OA morphological changes. The T2 values of femoral condyle (FC) (P < 0.0001) and groove (P = 0.0001) in patients with early stage knee OA were significantly increased in comparison to those in the control, while no significant differences in the T2 values of patellar and tibial plateau (TP) were observed between the patients and the control. The WORMS cartilage and osteophyte scores of the femoral articular cartilage were significantly higher than those in the patellar- (P = 0.001 and P = 0.007, respectively) and tibial- (P = 0.0001 and P < 0.0001, respectively) articular cartilage in the patients with early stage knee OA. CONCLUSIONS The degradation and destruction of the femoral articular cartilage demonstrated a greater degree of deterioration than those of the tibial- and patellar- articular cartilage in patients with early stage knee OA.

Analysis of non-traumatic truncal back pain in patients who visited an emergency room

To investigate epidemiology of acute non‐traumatic back pain using modern diagnostic methods in patients who visited an emergency room.

Eccentric contraction strength of knee extensor before and after anterior cruciate ligament reconstruction

Twelve men and eighteen women with a mean age of 22 (15–32) years who underwent anterior cruciate ligament (ACL) reconstruction using semitendinosus muscle tendon were studied. The quadriceps strength was isokinetically measured during concentric and eccentric contractions. When the muscle strength was examined before ACL reconstruction, the injured/uninjured ratio was 72.9% for eccentric contraction, which was significantly lower than the 81.4% for concentric contraction. For postoperative muscle, the injured/uninjured ratio was 98.6% for eccentric contraction and 80.6% for concentric contraction, showing better recovery of muscle strength for eccentric contraction. The observation of lower muscle strength for eccentric contraction than for concentric contraction in knees before ACL reconstruction may be explained by the fact that movements such as stop and turn become difficult due to ACL dysfunction. The result is that the patient avoids exerting eccentric knee extension and contraction forces even in daily living activities. On the other hand, once the joint instability is improved by ACL reconstruction, patients do not need to avoid movements such as stop and climbing down stairs that require eccentric contraction strength. This may account for good recovery of the muscle strength for eccentric contraction.RésuméDouze hommes et dix-huit femmes d’un âge moyen de 22 ans (15–32) qui avaient été opérés pour reconstruction du LCA en utilisant le tendon du demi-tendineux ont été étudiés. La force du quadriceps a été mesurée en isocinétique durant la contraction concentrique et excentrique. La force du quadriceps avant la reconstruction du LCA exprimée en ratio genou lésé/genou non lésé était de 72,9% pour la contraction excentrique, ce qui était significativement plus bas que le ratio de 81,4% pour la contraction concentrique. Une fois opéré, le même ratio était de 98,6% pour la contraction excentrique et de 80,6% pour la contraction concentrique. La constatation d’une diminution de la force de contraction excentrique avant la reconstruction du LCA s’explique par le fait que les mouvements de type «arrêt et rotation» sont difficiles avec un LCA lésé, ce qui fait que le patient évite la contraction excentrique même lors des activités de tous les jours. D’autre part, dès que l’instabilité du genou est améliorée par la reconstruction du LCA, les patients n’ont plus besoin d’éviter les mouvements comme d’arrêt ou de montée d’escaliers qui nécessitent une bonne force de contraction excentrique. Ceci doit être pris en compte pour une bonne récupération de la force musculaire en contraction excentrique.