Idiopathic and normal lateral lumbar curves: muscle effects interpreted by 12th rib length asymmetry with pathomechanic implications for lumbar idiopathic scoliosis

Background

The historical view of scoliosis as a primary rotation deformity led to debate about the pathomechanic role of paravertebral muscles; particularly multifidus, thought by some to be scoliogenic, counteracting, uncertain, or unimportant. Here, we address lateral lumbar curves (LLC) and suggest a pathomechanic role for quadrates lumborum, (QL) in the light of a new finding, namely of 12th rib bilateral length asymmetry associated with idiopathic and small non-scoliosis LLC.

Methods

Group 1: The postero-anterior spinal radiographs of 14 children (girls 9, boys 5) aged 9–18, median age 13 years, with right lumbar idiopathic scoliosis (IS) and right LLC less that 10°, were studied. The mean Cobb angle was 12° (range 5–22°). Group 2: In 28 children (girls 17, boys 11) with straight spines, postero-anterior spinal radiographs were evaluated similarly to the children with the LLC, aged 8–17, median age 13 years. The ratio of the right/left 12th rib lengths and it’s reliability was calculated. The difference of the ratio between the two groups was tested; and the correlation between the ratio and the Cobb angle estimated. Statistical analysis was done using the SPSS package.

Results

The ratio’s reliability study showed intra-observer +/−0,036 and the inter-observer error +/−0,042 respectively in terms of 95 % confidence limit of the error of measurements. The 12th rib was longer on the side of the curve convexity in 12 children with LLC and equal in two patients with lumbar scoliosis. The 12th rib ratios of the children with lumbar curve were statistically significantly greater than in those with straight spines. The correlation of the 12th rib ratio with Cobb angle was statistically significant. The 12th thoracic vertebrae show no axial rotation (or minimal) in the LLC and no rotation in the straight spine group.

Conclusions

It is not possible, at present, to determine whether the 12th convex rib lengthening is congenitally lengthened, induced mechanically, or both. Several small muscles are attached to the 12th ribs. We focus attention here on the largest of these muscles namely, QL. It has attachments to the pelvis, 12th ribs and transverse processes of lumbar vertebrae as origins and as insertions. Given increased muscle activity on the lumbar curve convexity and similar to the interpretations of earlier workers outlined above, we suggest two hypotheses, relatively increased activity of the right QL muscle causes the LLCs (first hypothesis); or counteracts the lumbar curvature as part of the body’s attempt to compensate for the curvature (second hypothesis). These hypotheses may be tested by electrical stimulation studies of QL muscles in subjects with lumbar IS by revealing respectively curve worsening or correction. We suggest that one mechanism leading to relatively increased length of the right 12 ribs is mechanotransduction in accordance with Wolff’s and Pauwels Laws.

24-h blood glucose pattern in type I and type II diabetics after oral treatment with pentoxifylline as assessed by artificial endocrine pancreas

Based on the known action of xanthine derivatives on the insulin secretion, the effect of pentoxifylline on carbohydrate homeostasis of type I (IDDM) and type II (NIDDM) diabetics was investigated. Pentoxifylline is known to exert a favorable influence on hemorheological disturbances in such patients. Twenty-four hour blood glucose pattern and insulin requirements were evaluated in type I and type II diabetics by the use of the artificial pancreas before and after a 14-day treatment with pentoxifylline 400 mg p.o. (Trental 400) t.i.d. During the stabilization period before treatment with pentoxifylline, NIDDM patients required 10.1 +/- 3.8 U of insulin and the IDDM 35 +/- 13.7 U. After 2 weeks on pentoxifylline, NIDDM required only 6.3 +/- 2.8 U (p less than 0.05) and IDDM 28.5 +/- 9.7 U (n.s.). Average blood glucose during the 24h decreased by 15.8 +/- 3.5% in NIDDM and by 10.3 +/- 2.5% in IDDM. Moreover, a significant smoothing of glucose fluctuations during the 24h was noted in both groups. It is concluded that pentoxifylline administered concurrently to any antidiabetic type of treatment leads to better blood glucose control as well as to prevention or delay of vascular complications.

Plasma fibronectin in normal subjects and in various disease states

Plasma fibronectin was determined in 121 normal adults and in 149 patients. Fibronectin levels in normals were strongly influenced by sex and age. The mean value of the protein in cancer patients did not differ from that in normal controls; however, patients with cryofibrinogenaemia or extensive liver metastases had lower values whereas those with obstructive jaundice due to pancreatic carcinoma had higher values than normal controls. Fibronectin levels were greatly increased in patients with primary biliary cirrhosis and moderately elevated in nephrotic syndrome. In patients with severe infection or sepsis, plasma fibronectin did not show a consistent pattern. Patients with overt disseminated intravascular coagulation, irrespective of its cause, had the lowest plasma fibronectin concentrations.