In vivo anatomy of the Neer and Hawkins sign positions for shoulder impingement

The Neer and Hawkins impingement signs are commonly used to diagnose subacromial pathology, but the anatomy of these maneuvers has not been well elucidated in vivo. This 3-dimensional open magnetic resonance imaging study characterized shoulder anatomy and rotator cuff impingement in 8 normal volunteers placed in the Neer and Hawkins positions. Subacromial and intraarticular contact of the rotator cuff was graded, and minimum distances were computed between the tendon insertion sites and the glenoid, acromion, and coracoid. Both the Neer and Hawkins maneuvers significantly decreased the distance from the supraspinatus insertion to the acromion and posterior glenoid and from the subscapularis insertion to the anterior glenoid. However, the Hawkins position resulted in significantly greater subacromial space narrowing and subacromial rotator cuff contact than the Neer position. In the Hawkins position, subacromial contact of the supraspinatus and infraspinatus was observed in 7 of 8 and 5 of 8 subjects, respectively. In contrast, rotator cuff contact with the acromion did not occur in any subject in the Neer position. Intraarticular contact of the supraspinatus with the posterosuperior glenoid was observed in all subjects in both positions. Subscapularis contact with the anterior glenoid was also seen in 7 of 8 subjects in the Neer position and in all subjects in the Hawkins position. This extensive intraarticular contact suggests that internal impingement may play a role in the Neer and Hawkins signs.     

Osteoporosis and depression: A historical perspective

In the early 1980s, researchers studying osteoporosis noted that depression was one of the major negative consequences of bone loss and fractures. These researchers believed that osteoporosis and fractures occurred first, causing a reactive depression. Meanwhile, a similar but distinct psychiatry literature noted that osteoporosis or bone loss appeared to be an undesirable consequence of major depression. Here, depression was seen as the causal factor, and osteoporosis was the outcome. The psychiatric perspective is more biological, based on the presence of hypercorticoidism in depressed individuals. Those who believe that osteoporosis leads to depression point out that depression is a consequence of many chronic illnesses. Regardless of the correct causal order, the strong positive relationship between osteoporosis and depression merits further clinical and research attention in the future.     

Review of adherence to medications for the treatment of osteoporosis

One of the major challenges of successful osteoporosis management is poor patient adherence to current therapies. Individuals who are nonadherent have significant consequences of reduced bone mineral density response, reduced bone marker suppression, and increased risk for fracture compared with individuals who are adherent. Although reducing the dosing interval from daily to weekly oral bisphosphonates has improved adherence, adherence with weekly bisphosphonates remains suboptimal. Barriers to adherence include patient health beliefs, inadequate patient education and age. Potential solutions include increased health care provider-patient interaction, and longer times between doses of medications.     

Enzymatic breakage of the cohesive end site of phage lambda DNA: terminase (ter) reaction.

An in vitro system is described for measuring the endonucleolytic conversion of the phage lambda cohesive end sites in concatemeric DNA to the cohesive chromosomal ends of the mature molecule. This enzymic process, known as the ter reaction, is catalyzed by purified lambda A gene protein. The reaction is markedly stimulated by ATP, Mg2+, spermidine, and one or more uncharacterized factors present in extracts of uninfected Escherichia coli cells. In vitro, the ter reaction proceeds in the absence of proheads under conditions that are similar to those previously found necessary for the formation of a DNA-A gene protein intermediate for the initiation of packaging.