Effect of selective capsulorrhaphy on the passive range of motion of the glenohumeral joint.

BACKGROUND: Capsulorrhaphy of the glenohumeral joint is a common surgical procedure for the treatment of instability caused by increased capsular laxity. The effect of capsulorrhaphy on the range of motion of the shoulder is poorly understood. METHODS: We simulated localized capsular contractures by selective capsular plications in eight human cadaveric shoulders and studied the effect of such plications on the passive range of glenohumeral abduction, flexion, and external and internal rotation in different degrees of abduction. A 0.5 or 1-N-m torque was applied to the humerus, and the range of glenohumeral motion was measured with electronic goniometers in three planes and compared with those of the intact shoulder. RESULTS: Anterosuperior capsular plication most markedly affected external rotation of the adducted arm, decreasing it by a mean of 30.1 degrees (p < 0.0001). Anteroinferior plication significantly reduced abduction by a mean of 19.4 degrees (p < 0.0001) and external rotation by a mean of 20.6 degrees (p = 0.0046). Posterosuperior plication mostly limited internal rotation of the adducted arm (mean decrease, 16.1 degrees, p = 0.0045). On the average, total anterior and total posterior plication each limited flexion by approximately 20 degrees (p = 0.005) and abduction by >or=15 degrees (p < 0.005), whereas total anterior plication limited external rotation by >30 degrees (p 20 degrees (p < 0.0001). Total inferior capsular plication restricted abduction (by a mean of 27.7 degrees, p = 0.0001), flexion, and rotation. Total superior plication restricted external rotation and flexion. CONCLUSIONS AND CLINICAL RELEVANCE: Localized plications of the glenohumeral joint capsule lead to predictable patterns of loss of glenohumeral mobility. If plication is planned, losses of movement can be anticipated. The findings of this study may assist surgeons in identifying the parts of the capsule that are contracted and that may need lengthening.

The effect of rotational malunion of the radius and the ulna on supination and pronation.

We have assessed the influence of isolated and combined rotational malunion of the radius and ulna on the rotation of the forearm. Osteotomies were made in both the radius and the ulna at the mid-diaphyseal level of five cadaver forearms and stabilised with intramedullary metal implants. Malunion about the axis of the respective forearm bone was produced at intervals of 10 degrees. The ranges of pronation and supination were recorded by a potentiometer under computer control. We examined rotational malunions of 10 degrees to 80 degrees of either the radius or ulna alone and combined rotational malunions of 20 degrees to 60 degrees of both the radius and ulna. Malunion of the ulna in supination had little effect on rotation of the forearm. Malunion of either the radius or of the ulna in pronation gave a moderate reduction of rotation of the forearm. By contrast, malunion of the radius in supination markedly reduced rotation of the forearm, especially with malunion greater than 60 degrees. Combined rotational malunion produced contrasting results. A combination of rotational malunion of the radius and ulna in the same direction had an effect similar to that of an isolated malunion of the radius. A combination in the opposite direction gave the largest limitation of the range of movement. Clinically, rotational malunion may be isolated or part of a complex angular/rotational deformity and rotational malunion may lead to marked impairment of rotation of the forearm. A reproducible method for assessing rotational malunion is therefore needed.