Quantitative analysis of the sympathetic innervation of the rat knee joint.

Retrograde tracing with Fluoro-Gold (FG) was used to identify the complete population of knee joint sympathetic postganglionic efferents in the lumbar sympathetic chain of adult female Wistar rats. In 6 rats, the total number and distribution of FG-labelled neurons in the lumbar sympathetic chain was determined. The rat knee joint is supplied by an average of 187+/-57 sympathetic afferents with the majority at the L3 and L4 levels. Immunohistochemistry using antibodies specific for tyrosine hydroxylase (TH), somatostatin (SS) or vasoactive intestinal polypeptide (VIP) revealed that 33 % of knee joint sympathetic afferents contained TH, 42 % contained VIP, and none contained somatostatin. Retrograde tracing with FG provided accurate and reproducible labelling of the joint-innervating subpopulation of sympathetic efferent neurons. This model lends itself to the further study of the molecular responses of this neuronal population in the various disorders and conditions affecting joints.

Anticoagulation in spinal surgery. A critical review of the literature.

OBJECTIVE: To determine the natural incidence of thromboembolic complications and the effect of thromboprophylaxis associated with elective spinal surgery. DATA SOURCES: A search of the MEDLINE database, using the key words anticoagulation, deep vein thrombosis (DVT) and spine, alone and in different combinations. Individual journals were also searched. Articles investigating the incidence or treatment (or both) of thromboembolism in elective spinal surgery were identified. STUDY SELECTION: Studies describing elective spinal surgery. The type of surgery, days of recumbency, methods of thromboprophylaxis, study design, surveillance methods, rates of DVT and pulmonary embolism (PE), and type and rates of complications of thromboprophylaxis were determined. DATA EXTRACTION: Single observer. DATA SYNTHESIS: Only 15 studies were found. Most were of poor statistical quality: 5 were level IV quality (nonrandomized, historic controls), 8 were level V quality (no controls, cases series), 1 was a level III study (nonrandomized, contemporaneous controls) and 1 was a level II study (small randomized study, moderate to high risk of error). The raw incidence of thromboembolic complications derived from these studies was 7.1% (14.1%) (mean [and SD]). However, because of the poor quality of these studies, this figure is suspect. CONCLUSIONS: The true incidence of thromboembolic complication in spinal surgery remains unknown. Recommendations for thromboprophylaxis cannot be made from the findings of these studies. There is a need for a well-designed, randomized controlled study to define the efficacy of thromboprophylaxis in elective spinal surgery.

Diagnostic peritoneal lavage versus abdominal computed tomography in blunt abdominal trauma: a review of prospective studies.

OBJECTIVE: To determine whether abdominal computed tomography (CT) or diagnostic peritoneal lavage (DPL) should be used in the evaluation of hemodynamically stable patients with blunt abdominal trauma and equivocal findings on physical examination. DATA SOURCE: MEDLINE. STUDY SELECTION: Prospective studies of hemodynamically stable trauma patients with blunt abdominal trauma and equivocal findings on physical examination that compared abdominal CT and DPL. DATA EXTRACTION: Data were extracted by a single observer. DATA SYNTHESIS: Most studies had excellent DPL results. The mean sensitivity was 98% (range from 90% to 100%), the mean specificity was 92% (range from 73% to 100%), the mean positive predictive value (PPV) was 82% (range from 57% to 92%), the mean negative predictive value (NPV) was 100% (range from 99% to 100%) and the mean accuracy was 93% (range from 80% to 98%). One study reported a low specificity (73%), PPV (57%) and accuracy (80%) for DPL, which may have been due to the loose criteria for red blood cells used in that study. The mean CT values were as follows: sensitivity 60% (range from 20% to 97%), specificity 98% (range from 91% to 100%), PPV 88% (range from 50% to 100%), NPV 84% (range from 76% to 93%) and accuracy 87% (range from 73% to 97%). In studies done in the mid-1980s the CT results were inferior, but they were improved in studies reported in the 1990s (sensitivity 88%, NPV 97%, accuracy 92%). These latest studies also suggest that CT and DPL are complementary rather than equivalent studies. CONCLUSION: DPL should be performed if there are no contraindications and no associated injuries that would be better delineated by CT, in which case abdominal CT is indicated.

The use of femoral head autograft shelf reconstruction and cemented acetabular components in the dysplastic hip.

In view of the controversy about bulk autografts to provide support for the acetabular cup in reconstruction of the dysplastic hip, a series of 15 dysplastic hips were investigated as follows: Femoral head autograft shelf reconstruction and cemented acetabular components were evaluated at an average follow-up period of 99 months after operation (range, 27-141 months). Hip rating scores and radiographic assessments were done on each patient before surgery and at postoperative examinations. The average preoperative hip score was 43.6 points (range, 22-82). The average hip score at review was 72.3 points (range, 48-100). The increase in hip scores was 29 points (range, -10 to +69). All grafts showed radiographic evidence of union to the pelvis at review. There was no resorption in five cases. The graft showed some resorption in eight cases, six of which were minor. None of the grafts or the acetabular components showed any signs of migration. Although the number of cases is small, the results show that bulk acetabular allografts can survive beneath cups in reconstructed dysplastic hips.