Background: Muscular forces drive proximal humeral fracture deformity, yet it is unknown if arm position can help mitigate such forces. Our hypothesis was that glenohumeral abduction and humeral internal rotation decrease the pull of the supraspinatus and subscapularis muscles, minimizing varus fracture deformity. Methods: A medial wedge osteotomy was performed in eight cadaveric shoulders to simulate a two-part fracture. The specimens were tested on a custom shoulder testing system. Humeral head varus was measured following physiologic muscle loading at neutral and 20° humeral internal rotation at both 0° and 20° glenohumeral abduction. Results: There was a significant decrease in varus deformity caused by the subscapularis (p<0.05) at 20° abduction. Significantly increasing humeral internal rotation decreased varus deformity caused by the subscapularis (p<0.05) at both abduction angles and that caused by the supraspinatus (p<0.05) and infraspinatus (p<0.05) at 0° abduction only. Conclusions Postoperative shoulder abduction and internal rotation can be protective against varus failure following proximal humeral fracture fixation as these positions decrease tension on the supraspinatus and subscapularis muscles. Use of a resting sling that places the shoulder in this position should be considered.

BACKGROUND AND PURPOSE: Following the positive results from recent trials on endovascular therapy (EVT), bridging therapy (intravenous alteplase plus EVT) is increasingly being used for the treatment of acute ischemic stroke. However, the optimal dose of intravenous alteplase remains unknown in centers where bridging therapy is actively performed. The optimal dose for eventual recanalization and positive clinical outcomes in patients receiving bridging therapy also remains unknown. METHODS: In this prospective Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED) sub-study, we explored the outcomes following treatment with two different doses (low- [0.6 mg/kg] or standard-dose [0.9 mg/kg]) of intravenous alteplase across 12 Korean centers where EVT is actively performed. The primary endpoint was a favorable outcome at 90 days (modified Rankin Scale scores 0 to 1). Secondary endpoints included symptomatic intracerebral hemorrhage (ICH) in all patients, and the recanalization rate and favorable outcome in patients who underwent cerebral angiography for EVT (ClinicalTrials.gov, number NCT01422616). RESULTS: Of 351 patients, the primary outcome occurred in 46% of patients in both the standard-(80/173) and low-dose (81/178) groups (odds ratio [OR], 1.14; 95% confidence interval [CI], 0.72 to 1.81; P=0.582), although ICHs tended to occur more frequently in the standard-dose group (8% vs. 3%, P=0.056). Of the 67 patients who underwent cerebral angiography, there was no significant difference in favorable functional outcome between the standard- and low-dose groups (39% vs. 21%; OR, 2.39; 95% CI, 0.73 to 7.78; P=0.149). CONCLUSIONS: There was no difference in functional outcome between the patients receiving different doses of alteplase in centers actively performing bridging therapy.
Cerebral Angiography ; Cerebral Hemorrhage ; Cerebral Infarction ; Humans ; Hypertension ; Intracranial Hemorrhages ; Prospective Studies ; Stroke ; Thrombectomy ; Tissue Plasminogen Activator