Impact of shoulder rotation on neck-shaft angle: A clinical study.

BACKGROUND: Two recent experimental studies evaluated the influence of shoulder rotation on neck-shaft angle, with conflicting results. However, there have been no clinical studies of whether this angle varies in different shoulder positions. The present study aimed to determine whether shoulder rotation affects neck-shaft angle on standard radiographs in patients with complaints of shoulder pain. HYPOTHESIS: Shoulder rotation does not affect neck-shaft angle. MATERIALS AND METHODS: A prospective study was conducted in selected patients with shoulder pain. Three true anterior-posterior radiographic views were obtained: in neutral rotation, 30° external rotation, and internal rotation with patient's arm in a sling. The X-rays were evaluated by three shoulder and elbow surgeons. Inter- and intra-observer reliability was evaluated by intraclass correlation coefficient (ICC). RESULTS: Neck-shaft angle on true AP view did not differ between neutral rotation and 30° external rotation: 132±6° and 130±9°, respectively (P>0.999). In internal rotation with the hand resting on the abdomen, neck-shaft angle was 145±6°: i.e., significantly different (P<0.001) to the other two positions. Intra- and inter-observer correlation demonstrated excellent reliability. CONCLUSIONS: Radiographic neck-shaft angle was significantly different in internal rotation with the patient's arm in a sling, compared with views in neutral or 30° external rotation. Intra- and inter-observer correlation showed excellent reliability. LEVEL OF EVIDENCE: II, comparative prospective study.

Osteoid osteoma of the glenoid: Arthroscopic treatment.

Osteoid osteoma is a benign tumor that is rarely found in the scapula. We report a clinical case involving a 36-year-old female patient who suffered from progressive pain in her right shoulder for 1 year. This patient was initially diagnosed with impingement syndrome and was treated unsuccessfully with medication and physical therapy for approximately 2 months. Based on imaging exams, a juxta-articular osteoid osteoma of the glenoid was identified. The patient underwent a shoulder arthroscopy that included tumor removal and treatment of the resulting chondral lesion. At 6-, 12- and 36-month assessments, the patient was asymptomatic, with a normal range of motion and experienced a pain intensity corresponding to 0 points on the Visual Analog Scale (VAS) and 35 points on the University of California, Los Angeles (UCLA) Scale. A postoperative MRI indicated the absence of any residual tumor tissue or inflammatory signs. We believe that the approach described in this paper allows juxta-articular osteoid osteomas to be accessed in a minimally invasive manner and permits not only adequate resection but also the treatment of chondral lesions that could remain after tumor resection.

Assessment of the function and resistance of sternoclavicular ligaments: A biomechanical study in cadavers.

BACKGROUND: Few biomechanical studies have assessed the resistance of the ligamentous structures of the sternoclavicular joint, and none have reproduced the physiological movements of the joint. Determining the structures that are injured in sternoclavicular dislocations is important for the surgical planning of acute or chronic ligament reconstruction. METHODS: Forty-eight joints from 24 human cadavers were studied, and they were divided into 4 groups of 12 joints each (retraction, protraction, depression and elevation). Biomechanical testing assessed primary and secondary failures. The mechanical resistance parameters between movements that occurred on the same plane (depression versus elevation, protraction versus retraction) were compared. RESULTS: The posterior sternoclavicular ligament was the most injured structure during the protraction test, but it was not injured during retraction. The anterior sternoclavicular ligament was the most affected structure during retraction and depression. The costoclavicular ligament was the most affected structure during elevation. Joint resistance was significantly greater during protraction movements when compared to retraction (P<0.05). CONCLUSION: The anterior sternoclavicular ligament was the most affected structure during retraction and depression movements. During protraction, lesions of the posterior sternoclavicular ligament were most frequent during elevation, and the costoclavicular ligament was the most frequently injured ligament. The resistance of the sternoclavicular joint was significantly greater during protraction movement when compared to retraction. LEVEL OF EVIDENCE: IV, basic science, biomechanics, cadaver model.

Studies on mineral nutrition of the coffee plant (Coffea arabica L. cv. Catuaí Vermelho): LXIV. Remobilization and re-utilization of nitrogen and potassium by normal and deficient plants

Remobilization and re-utilization of 15N and 85Rb labelled nitrogen and potassium reserves for new growth and fruit formation was studied under greenhouse conditions using both normal and deficient young coffee plants. It was found that K reserves are used in higher proportion than is stored N by fruits and other organs. The export of N by organs of residence in the normal plants obeyed the following proportions of the total: leaves 47 percent-58 percent, branches and flower buds 21 percent-27 percent, roots 21 percent-32 percent. The corresponding figures in the case of deficient plants were: leaves 49 percent-65 percent, branches and flower buds 21 percent-27 percent, roots 14 percent-25 percent. Re-utilization of K took place in the following proportions in the normal plants: leaves 54 percent-64 percent, branches and flower buds 20 percent-21 percent, roots 30 percent-41 percent. In K deficient plants the figures were: leaves 62 percent-79 percent, branches and flower buds 1.2 percent-4.4 percent, roots 20 percent-33 percent. In tissues formed after the initiation of flowering buds, the demand for N is met by reserves as follows: normal plants: fruits 20.6 percent-24.8 percent, leaves 15.6 percent-19.4 percent, twigs 19 percent-20.5 percent; deficient plants: fruits 43.5 percent-48.5 percent, leaves 48.1 percent-51.9 percent, twigs 46 percent-53 percent. The K needs for new tissues are met in the order: normal plants: fruits 40 percent-45.8 percent, leaves 27 percent-37.6 percent, twigs 26 percent-33.1 percent; deficient plants: fruits 65.7 percent-81.5 percent, leaves 52.6 percent-68.4 percent, twigs 62 percent-86.1 percent. Fruits represent the main sink for both N and K. Re-utilization of both elements is higher in the case of deficient plants.

Studies on mineral nutrition of the coffee plant (Coffea arabica L. cv. Catuaí Vermelho). LXIV. Remobilization and re-utilization of nitrogen and potassium by normal and deficient plants.

Remobilization and re-utilization of 15N and 85Rb labelled nitrogen and potassium reserves for new growth and fruit formation was studied under greenhouse conditions using both normal and deficient young coffee plants. It was found that K reserves are used in higher proportion than is stored N by fruits and other organs. The export of N by organs of residence in the normal plants obeyed the following proportions of the total: leaves 47%-58%, branches and flower buds 21%-27%, roots 21%-32%. The corresponding figures in the case of deficient plants were: leaves 49%-65%, branches and flower buds 21%-27%, roots 14%-25%. Re-utilization of K took place in the following proportions in the normal plants: leaves 54%-64%, branches and flower buds 20%-21%, roots 30%-41%. In K deficient plants the figures were: leaves 62%-79%, branches and flower buds 1.2%-4.4%, roots 20%-33%. In tissues formed after the initiation of flowering buds, the demand for N is met by reserves as follows: normal plants: fruits 20.6%-24.8%, leaves 15.6%-19.4%, twigs 19%-20.5%; deficient plants: fruits 43.5%-48.5%, leaves 48.1%-51.9%, twigs 46%-53%. The K needs for new tissues are met in the order: normal plants: fruits 40%-45.8%, leaves 27%-37.6%, twigs 26%-33.1%; deficient plants: fruits 65.7%-81.5%, leaves 52.6%-68.4%, twigs 62%-86.1%. Fruits represent the main sink for both N and K. Reutilization of both elements is higher in the case of deficient plants.

Myocardial infarction and histamine release.

On the basis of previous data suggesting the involvement of cardiac histamine in ischemic heart disease (IHD), we evaluated plasma histamine (H) and creatine-kinase isoenzyme (CK-MB) level in cardiac and healthy subjects. 20 patients with acute myocardial infarction (AMI) (10 developing AMI in Hospital, thus making possible the detection of plasma H level before acute event), 10 patients with IHD not developing AMI and 10 presumably healthy subjects were admitted to the study. 15 of all patients with AMI showed a correlated H and CK-MB trend during AMI reaching the highest peak 24 hours after onset of pain. 7 of the patients with IHD who developed AMI in Hospital showed a slightly higher plasma H level, before AMI, than those with IHD who did not develop AMI. A possible role of histamine in the pathogenesis of AMI is discussed.