Clinical outcomes do not support arthroscopic posterior capsular release in addition to anterior release for shoulder stiffness: a randomized controlled study.

BACKGROUND: Arthroscopic capsular release is an effective treatment for shoulder stiffness, yet its extent is controversial. PURPOSE: To compare the clinical outcomes of arthroscopic capsular release in patients with and without posterior extended capsular release for shoulder stiffness. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Between January 2008 and March 2011, 75 patients who underwent arthroscopic capsular release for shoulder stiffness were enrolled and randomized into 2 groups. In group I (n = 37), capsular release was performed, including release of the rotator interval and anterior and inferior capsule. In group II (n = 38), capsular release was extended to the posterior capsule. The American Shoulder and Elbow Surgeons score, Simple Shoulder Test, visual analog scale for pain, and range of motion (ROM) were used for the evaluation before surgery and at 3, 6, and 12 months after surgery and at the last follow-up. RESULTS: Preoperative demographic data of age, sex, symptom duration, and clinical outcomes showed no significant differences (P > .05). The average follow-up was 18.4 months. Both groups showed significantly increased ROM at the last follow-up compared with preoperative ROM (P < .05). At the last follow-up, no statistical differences were found (P > .05) between groups I and II in American Shoulder and Elbow Surgeons score (91.3 vs. 79.5), Simple Shoulder Test (83.3 vs. 83.3), and visual analog scale (1.5 vs. 2.2). There were also no statistical differences between the 2 groups at the last follow-up (P > .05) in ROM: forward flexion, 145.2° vs. 143.3°; external rotation with 90° of abduction, 88.1° vs. 86.2°; external rotation at side, 88.9° vs. 82.9°; and internal rotation, 9.1° vs. 8.3°. CONCLUSION: Posterior extended capsular release might not be necessary in arthroscopic surgery for shoulder stiffness.

Accelerated premature stress-induced senescence of young annulus fibrosus cells of rats by high glucose-induced oxidative stress.

PURPOSES: Diabetes mellitus (DM) is thought to be an important aetiological factor in intervertebral disc degeneration. A glucose-mediated increase of oxidative stress is a major causative factor in development of diseases associated with DM. The aim of this study was to investigate the effect of high glucose on mitochondrial damage, oxidative stress and senescence of young annulus fibrosus (AF) cells. METHODS: AF cells were isolated from four-week-old young rats, cultured, and placed in either 10 % FBS (normal control) or 10 % FBS plus two different high glucose concentrations (0.1 M and 0.2 M) (experimental conditions) for one and three days. We identified and quantified the mitochondrial damage and reactive oxygen species (ROS) (oxidative stress). We also identified and quantified the occurrence of senescence and telomerase activity. Finally, the expressions of proteins were determined related to replicative senescence (p53-p21-pRB) and stress-induced senescence (p16-pRB). RESULTS: Two high glucoses enhanced the mitochondrial damage in young rat AF cells, which resulted in an excessive generation of ROS in a dose- and time-dependent manner for one and three days compared to normal control. Two high glucose concentrations increased the occurrence of senescence of young AF cells in a dose- and time-dependent manner. Telomerase activity declined in a dose- and time-dependent manner. Both high glucose treatments increased the expressions of p16 and pRB proteins in young rat AF cells for one and three days. However, compared to normal control, the expressions of p53 and p21 proteins were decreased in young rat AF cells treated with both high glucoses for one and three days. CONCLUSIONS: The present study demonstrated that high glucose-induced oxidative stress accelerates premature stress-induced senescence in young rat AF cells in a dose- and time-dependent manner rather than replicative senescence. These results suggest that prevention of excessive generation of oxidative stress by strict blood glucose control could be important to prevent or to delay premature intervertebral disc degeneration in young patients with DM.

How effective is multiple needle puncturing for medial soft tissue balancing during total knee arthroplasty? A cadaveric study.

We investigated the quantitative effect and risk factors for over-release during multiple needle puncturing (MNP) for medial gap balancing in varus total knee arthroplasty (TKA). Of the ten pairs of cadaveric knees, one knee from each pair was randomly assigned to undergo MNP in extension (E group), while the other knee underwent MNP in flexion (F group). The increased extension and 90° flexion gaps after every five needle punctures were measured until over-release occurred. The extension gap (< 4mm) and the 90° flexion gap (< 6mm) gradually increased in both groups. The 90° flexion gaps increased more selectively than did the extension gaps. MNP in the flexed knee, a narrow MCL, and severe osteoarthritis were associated with a smaller number of MNPs required to over-release.