Superior capsular reconstruction using a porcine dermal xenograft for irreparable rotator cuff tears: outcomes at minimum two-year follow-up.

PURPOSE: To evaluate midterm outcomes of arthroscopic superior capsular reconstruction (SCR) using a decellularized porcine dermal xenograft in patients with massive, irreparable rotator cuff tears and to determine the influence of concomitant, repairable subscapularis tears. METHODS: This is a retrospective study of 56 patients with a minimum 2-year follow-up. Preoperative and postoperative range of motion, American Shoulder and Elbow Surgeons score, Subjective Shoulder Value, and visual analog score for pain were measured. Postoperative data were collected at 3, 6, 12, 24, and 36 months. RESULTS: Of the 56 patients who underwent arthroscopic SCR, there were 39 men and 17 women. The mean age at operation was 65 ± 9 years, and the mean follow-up was 34 ± 8 months. The mean preoperative American Shoulder and Elbow Surgeons improved from 41 ± 19 to 78 ± 18 at 24 weeks, to 86± 16 at 12 months, and to 90±9 at 24 months, P < .0001. Similarly, the mean preoperative Subjective Shoulder Value improved from 39 ± 17 to 74 ± 18 at 24 weeks, to 80 ± 18 at 12 months, and to 80 ± 11 at 24 months, P < .0001. The mean preoperative visual analog score improved from 6.5 ± 2.1 to 1.4 ± 2.2 at 24 weeks, to 0.7± 1.1 at 12 months, and to 0.2 ± 0.4 at 24 months, P < .0001. There were no differences in outcome scores between patients with intact vs. repaired subscapularis. Similarly, no statistically significant differences were found in forward flexion or external rotation after SCR between patients with an intact vs. repaired subscapularis. Failure of the SCR graft was observed on magnetic resonance imaging in 14 patients, 4 of whom opted for revision to reverse shoulder arthroplasty. Eleven patients were truly pseudoparalytic before surgery; in 5 cases, pseudoparalysis was reversed after SCR. CONCLUSIONS: SCR can alleviate pain and disability from irreparable rotator cuff tears and provide significant improvements in shoulder function; however, the xenograft technique resulted in inconsistent reversal of true pseudoparalysis. No difference was found between patients who required concomitant subscapularis repair vs. those who did not.

Effects of systemic and regional taurine on skeletal muscle function following ischaemia-reperfusion injury.

INTRODUCTION: Tissues subjected to prolonged ischaemia are paradoxically further damaged when their perfusion is restored. The mechanisms underlying this ischaemia-reperfusion injury are complex, but oxidative attack is a central feature. Among the therapeutic agents used to attenuate ischaemia-reperfusion injury, endogenous agents such as taurine which form part of the native defence mechanism against oxidative damage are of particular interest. METHODS: Using a model of hindlimb ischaemia-reperfusion injury in the rat, taurine solution was administered either into the operated hindlimb, into the systemic circulation, or both. Contraction strengths of gastrocnemius biopsies from the operated and contralateral (control) hindlimbs of each animal were measured. RESULTS: Fast twitch strength was impaired significantly by ischaemia-reperfusion injury, and taurine injected into the operated limb conferred partial protection. A similar trend was observed for tetany, but protection by taurine was not statistically significant for tetanic contraction strength. CONCLUSION: Preservation of fast twitch strength following ischaemia-reperfusion injury by administration of taurine before ischaemia has clinical potential. However, delivery to the affected tissues during ischaemia presents technical difficulties.

Midpalmar space hematoma mimicking compartment syndrome of the hand.

A hematoma in the midpalmar space following a crush injury produced the signs and symptoms of compartment syndrome. The clinical presentation, findings at surgery, and likely pathogenesis are discussed.