Inter-rater reliability of the Rasch-modified medical research council scoring criteria for manual muscle testing in neuromuscular diseases.

It was argued that researchers and clinicians are not able to make judgments between most categories of the original Medical Research Council (MRC) scale and that a modified short version would reach higher agreement levels. We aimed to assess the inter-rater reliability for both the original and the Rasch-modified MRC scoring criteria of Manual Muscle Strength tests (MMSt) in patients with neuromuscular diseases. Two MRC scoring criteria were used to score muscle strength using MMSt in 40 muscle groups of the upper and lower limbs in patients with neuromuscular disorders. Three investigators performed the evaluations; the order of the MMSt and the use of the scales were performed according to the preferences of the investigators. The agreement coefficient (Gwet's AC2 ) was used to compute the reliability. Sixty patients (mean age of 39.3 years ± 15.2) with neuromuscular diseases were included. The mean AC2 for the muscle groups of the upper limbs ranged from 0.82 to 0.96 using the modified MRC scale and from 0.86 to 0.96 using the original MRC scale. The AC2 for the lower limb muscle groups ranged from 0.80 to 0.91 (modified MRC scale) and from 0.87 to 0.93 (original MRC scale). These values might be interpreted as "almost perfect agreement" with no significant differences between the scales. The results indicate that both MRC scoring criteria have significant reliability among trained observers. Moreover, the Rasch-modified MRC scale is as reliable as the original MRC scale and can be used in future clinical studies.

Identification of adequate vehicles to carry nerve regeneration inducers using tubulisation.

BACKGROUND: Axonal regeneration depends on many factors, such as the type of injury and repair, age, distance from the cell body and distance of the denervated muscle, loss of surrounding tissue and the type of injured nerve. Experimental models use tubulisation with a silicone tube to research regenerative factors and substances to induce regeneration. Agarose, collagen and DMEM (Dulbecco's modified Eagle's medium) can be used as vehicles. In this study, we compared the ability of these vehicles to induce rat sciatic nerve regeneration with the intent of finding the least active or inert substance. The experiment used 47 female Wistar rats, which were divided into four experimental groups (agarose 4%, agarose 0.4%, collagen, DMEM) and one normal control group. The right sciatic nerve was exposed, and an incision was made that created a 10 mm gap between the distal and proximal stumps. A silicone tube was grafted onto each stump, and the tubes were filled with the respective media. After 70 days, the sciatic nerve was removed. We evaluated the formation of a regeneration cable, nerve fibre growth, and the functional viability of the regenerated fibres. RESULTS: Comparison among the three vehicles showed that 0.4% agarose gels had almost no effect on provoking the regeneration of peripheral nerves and that 4% agarose gels completely prevented fibre growth. The others substances were associated with profuse nerve fibre growth. CONCLUSIONS: In the appropriate concentration, agarose gel may be an important vehicle for testing factors that induce regeneration without interfering with nerve growth.