Quadriceps muscle and fibre cross-sectional areas (CSA), torque and neural activation were studied in seven healthy males during 6 months of weight training on alternate days with six series of eight unilateral leg extensions at 80% of one repetition maximum. After training, the quadriceps cross-sectional area increased by 18.8 +/- 7.2% (P < 0.001) and 19.3 +/- 6.7% (P < 0.001) in the distal and proximal regions respectively, and by 13.0 +/- 7.2% (P < 0.001) in the central region of the muscle. Hypertrophy was significantly different between and within the four constituents of the quadriceps. Biopsies of the vastus lateralis at mid-thigh did not show any increase in mean fibre cross-sectional area. Maximum isometric voluntary torque increased by 29.6 +/- 7.9%-21.1 +/- 8.6% (P < 0.01-0.05) between 100 degrees and 160 degrees of knee extension, but no change in the optimum angle (110 degrees-120 degrees) for torque generation was found. A 12.0 +/- 10.8% (P < 0.02) increase in torque per unit area together with a right shift in the IEMG-torque relation and no change in maximum IEMG were observed. Time to peak isometric torque decreased by 45.8% (P < 0.03) but no change in time to maximum IEMG was observed. In conclusion, strength training of the quadriceps results in a variable hypertrophy of its components without affecting its angle-torque relation. The increase in torque per unit area, in the absence of changes in IEMG, may indicate changes in muscle architecture. An increase in muscle-tendon stiffness may account for the decrease in time to peak torque.

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The recurrence rate deteriorated with time. Involvement in contact sports and overhead activities appears to be a risk factor for recurrence of instability, although this could not be proved statistically with the numbers available, whereas age, gender, and number of preoperative dislocations did not reveal any correlation with recurrence. Degenerative changes of the glenohumeral joint were noted but had no significant effect on the clinical outcomes.

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The tendon of the long head of the biceps (LHB) is a common source of pain in the shoulder, and the surgical treatments proposed are tenotomy or tenodesis performed in different ways. The purpose of this study is to compare the clinical results (objective and subjective) of tenotomy versus soft tissue tenodesis. One-hundred and four patients with an isolated LHB pathology, arthroscopically treated between 2004 and 2007, were observed retrospectively. Forty-eight of these patients were treated with tenotomy and 56 with a soft tissue tenodesis technique. All the patients were evaluated by an independent observer with a minimum follow-up of 2 years which included VAS, DASH questionnaire, Constant score and ROM evaluation with a goniometer. All these evaluations were performed pre- and post-operatively. An independent expert radiologist then performed an ultrasound examination only in the post-operative evaluation of the tenodesis group looking to confirm the effectiveness of the procedure. In both groups, the scores were significantly improved. In the tenotomy group, 16.6 % of the patients had bicipital cramps for a mean post-operative time of 1 month. Constant score improved in both groups: 46.6 to 86.1 in tenotomy group and 48.9-84.9 in tenodesis group; VAS improved from 8.4 to 1.5 in tenotomy group and from 8.8 to 1.4 in tenodesis group; DASH scores changed from 42.5 to 13.6 in tenotomy group and from 55.8 to 11.4 in tenodesis group. Popeye sign was present in 37.5 % in the tenotomy group and in 5.3 % in tenodesis group. In 3 patients of the tenodesis group, ultrasound revealed complete failure of the tenodesis. In conclusion, both procedures are effective in terms of treatment of LHB pathologies. Tenotomy does not require specific post-operative treatment and is easy to perform, but cramp and Popeye sign may occur after surgery. The soft tissue tenodesis technique is an easy and cost-effective way to perform tenodesis with good results, especially in preventing the Popeye sign, but requires a longer rehabilitation time. Level of evidence IV.

Arthroscopic transtendon partial articular supraspinatus tendon avulsion-type rotator cuff repair was a reliable procedure that resulted in a good outcome in terms of pain relief and shoulder scores in 98% of the 54 patients. Better results could be expected in patients with less tendon retraction, a larger footprint exposure, of younger age, and with a clinical history of trauma.

Peak blood lactate ([Labl]peak) and blood lactate concentration ([Labl]) vs. workload (W) relationships during acclimatization to altitude and in the deacclimatization were evaluated in 10 Caucasian lowlanders at sea level (SL0); after approximately 1 wk (Alt1wk), 3 wk (Alt3wk), and 5 wk (Alt5wk) at 5,050 m; and weekly during the first 5 wk after return to sea level (SL1wk-SL5wk). Incremental bicycle ergometer exercises (30 W added every 4 min up to exhaustion) were performed. At Alt1wk and at Alt5wk, the experiments were repeated in hypobaric normoxia (Alt1wk-O2 and Alt5wk-O2). [Labl] was determined at rest and during the last approximately 30 s of each W. [Labl]peak was taken as the highest [Labl] during recovery. Acid-base status (pH and concentration of HCO-3 in arterialized capillary blood) was determined at rest. Mean [Labl]peak values were 11.5 (SL0), 8.0 (Alt1wk), 6.4 (Alt3wk), 6.3 (Alt5wk), 8.0 (SL1wk), 9.4 (SL2wk), 10.8 (SL3wk), 11.3 (SL4wk), and 11.6 (SL5wk) mM. At Alt1wk-O2 and Alt5wk-O2, peak W increased, compared with Alt1wk and Alt5wk, whereas no changes were observed for [Labl]peak. [Labl] vs. W was shifted to the left (i.e., higher [Labl] values were found for the same W) at Alt1wk compared with SL0 and partially shifted back to the right (i.e., lower [Labl] values were found for the same W) at Alt3wk and Alt5wk. At Alt1wk-O2 and Alt5wk-O2, [Labl] vs. W values were superimposed on that at SL0. At SL1wk-SL5wk, [Labl] vs. W values were shifted to the right compared with that at SL0. At Alt1wk, a condition of respiratory alkalosis was found, which was only partially compensated for during acclimatization. At SL1wk, the acid-base status was back to normal. We conclude that 1) the reduced [Labl]peak at altitude is still present for 2-3 wk after return from altitude; is not attributable to reduced peak W nor to hypoxia per se, nor to a reduced buffer capacity; alternatively, it could be related to some central determinants of fatigue. 2) The [Labl] vs. W leftward shift at altitude was due to hypoxia per se. 3) The factor(s) responsible for the [Labl] vs. W partial rightward shift during acclimatization could still be effective during the first weeks after return to sea level.