Electrical stimulation superimposed onto voluntary muscular contraction reduces deterioration of both postural control and quadriceps femoris muscle strength.

Fatiguing exercise of the quadriceps femoris muscle degrades postural control in human subjects. The aim of this work was to compare the effects of the fatigue of the quadriceps femoris induced by voluntary muscular contraction (VC), and by electrical stimulation (ES) superimposed onto voluntary muscular contraction (VC+ES), on postural control and muscle strength. Fourteen healthy young adults participated in the study. Postural control and muscle strength were evaluated using a stable force platform and an isokinetic dynamometer, respectively, before (PRE condition) and after the completion of each fatiguing exercise (immediately: POST condition; after a 5 min recovery time: POST 5 condition). In POST, both postural control and muscle strength were impaired by both fatiguing exercises. However, the impairment was higher for VC than for VC+ES. In POST 5, for both fatiguing exercises, postural control recovered its initial level while muscle strength did not. These results suggest that superimposing ES onto voluntary muscular contractions (VCs) impaired muscle strength and postural control less than did VCs alone. However the duration of recovery of these two neurophysiological functions did not differ for the two fatiguing exercises. For both exercises, postural control was restored faster than the ability to produce muscular strength.

[Rotator cuff ruptures with predominant involvement of the subscapular tendon]. / Ruptures de la coiffe des rotateurs avec atteinte prédominante du sous-scapulaire.

Among the all rotator cuff tears, the subscapularis lesions are quite rare. But a careful analysis leads to recognize them specially in case of antero-medial impingement between the coracoid process and the head of the humerus. This study of 25 observations where the rupture of the subscapularis was the predominant lesion, allows to emphasize some characteristics of them. The patients are often younger than for the other ruptures, a traumatic experience is not rare at the beginning of the history, the pain is usually the first symptom before the functional disability, the alterations of the rotator-interval and of the biceps tendon are very frequent, the arthroscanner is a very good help for the diagnosis and satisfying stitches are possible in case of early diagnoses. Lastly, the prognosis of these limited lesions is quite different than the one of very large cuff tears including the suscapularis tendon.

[*primary osteonecrosis of the medial femoral condyle. Unicompartmental or total replacement?]. / L'ostéonécrose primitive du condyle fémoral interne. Remplacement unicompartimental ou total?

We have inserted 18 Mod II unicondylar knee replacements for idiopathic necrosis of the medial femoral condyle. The age of the patients at operation averaged 72 years, with a range of 49 to 90. The average length of follow up at review was 4 years 6 months, with a range of 2 to 8 years. The only notable complication was deterioration of the lateral compartment if operation had produced overcorrection of the tibiofemoral angle. The stability, level of pain, range of movement and function was satisfactory in 95% of the knees. The average flexion obtained was 115 degrees, and was deliberately restricted to this level to diminish stress on the lateral side. It did not result in aseptic loosening. Most knee flexion deformities were corrected at operation. Laxity and instability before operation were usually due to bone loss rather than ligament insufficiency, and were corrected by the prosthesis. A varus deformity of more than 10 degrees, a flexion deformity greater than 15 degrees or femorotibial subluxation were not considered to be contraindications to this operation.