Treatment of high-energy supracondylar/intercondylar fractures of the distal humerus

Operative treatment of high-energy intra-articular fractures of the distal humerus is challenging and controversial. We conducted a retrospective study at a Level I trauma center to evaluate the results of a specific treatment protocol. Seventy-one patients were treated through a posterior olecranon osteotomy. Capsulectomy was performed in patients who perceived their functional range of motion to be limited after an average of 10~months. Clinical followup consisted of physical examination, radiography, and completion of the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. Average followup duration was 22 (range, 6 to 70) months. Sixty-five percent of the patients achieved excellent or good results, 28% fair, and 7% poor. Thirty-one percent underwent capsulectomy, with 59% of those patients achieving excellent or good results. This is the largest series reported to date. Our patients experienced mild functional impairment and a low rate of nonunion. We advocate capsulectomy for patients with limited range of motion postoperatively.

Episodic and semantic memory tasks activate different brain regions in Alzheimer disease

OBJECTIVE

To compare brain activity identified by fMRI in subjects with Alzheimer disease (AD) and older healthy controls (HCs) performing an episodic/working memory (EWM) and semantic memory (SM) task.

METHODS

Nine AD (mean age 73.6) and 10 HC (mean age 71.8) subjects underwent an fMRI memory paradigm. Tasks comprised 1) baseline (recognizing a single digit presented for 1 second), 2) SM (addition of two single digits, always producing a single digit answer), and 3) EWM (recall of the previous single digit on the stimulus of the next digit). Each condition was presented in 2-minute blocks with a shorter and longer time interval for the first and second minute within blocks.

RESULTS

Comparing AD and HC subjects, there were no activated brain regions in common for EWM > SM, but left anterior cingulate (Brodmann area [BA] 24, 0, 31, 4) and left medial frontal lobe gyrus (BA 25, -6, 23, -15) were activated by both groups for SM > EWM. Key differences were that for EWM > SM, HC subjects activated the right parahippocampal gyrus, whereas subjects with AD activated the right superior frontal gyrus and left uncus.

CONCLUSIONS

Subjects with Alzheimer disease (AD) recruited brain regions for easier episodic/working memory (EWM) tasks used by healthy controls (HCs) for more difficult EWM tasks. AD subjects recruited brain regions for semantic memory tasks used by HCs for more difficult EWM tasks. The authors propose a functional "memory reserve" model of compensatory recruitment according to task difficulty and underlying neuropathology.