Spotty Bone Marrow: A Frequent MRI Finding in the Feet of Ballet Dancers.

INTRODUCTION: Bone marrow signal abnormalities on magnetic resonance imaging (MRI) are common in athletes. However, few studies evaluate the MRI appearance of bone marrow in the feet of ballet dancers. Our study aims to describe the "spotty bone marrow" (SBM) pattern in the tarsal bones of a cohort of ballet dancers, establishing its prevalence, distribution, potential associations, and evolution.
Methods: Eighty-six MRIs of 68 ankles in 56 ballet dancers were retrospectively reviewed for mar- row signal alterations, which were classified as focal or SBM (defined as patchy fluid-sensitive signal hyperintensity spanning more than one location or tarsal bone). When SBM involved the talus, its anatomic distribution in the bone and morphologic pattern were recorded. Additional osseous and soft tissue findings were documented. For subjects with more than one MRI of the same ankle, the SBM's evolution was monitored.
Results: Spotty bone marrow was identified in 44 ankles (65%). Spotty bone marrow was isolated to the talus (44%), present in all tarsal bones (25%), or distributed between the talus and one to three other tarsal bones (31%). In the talus, The SBM involved the entire bone (65%), the neck and body (31%), or the head and neck (4%). The SBM most commonly showed a random morphologic pattern (87%) but occasionally showed a peripheral predominance (13%). There was no statistically significant difference in the prevalence of other pathologies in ankles with and without SBM. In eight ankles with a follow-up MRI, the SBM worsened in one, remained stable in two, and improved in five ankles. None progressed to a stress fracture.
Conclusion: Spotty bone marrow is an MRI finding frequently encountered in ballet dancers. It is usually self-limiting and should not be misinterpreted as a more aggressive pathology.

In vitro evaluation of extemporaneously compounded slow-release capsules containing morphine sulfate or oxycodone hydrochloride.

The in vitro performance of extemporaneously compounded morphine sulfate and oxycodone hydrochloride slow-release capsules was evaluated. Capsules containing varying amoutns of morphine sulfate (15, 60, 200 mg) or oxycodone hydrochloride (10, 80, 200 mg) were prepared and provided by a Phoenix, Arizona, pharmacy. The capsules also contained 40% Methocel E4M Premium to slow the release of their active ingredient and sufficient lactose to fill the capsules. Three batches of each capsule strength were prepared, and replicates from each batch were evlauated using United Stated Pharmacopeia dissolution apparatus II. Samples were taken at regular time intervals over 24 hours. After 1 hour the pH of the dissolution medium was adjusted form 1.2 to 4.0, and after 2 hours the pH was adjusted to 6.8. The amount of drug released at each time point was determined spectrophotometrically. The compounded capsules released 14% to 23%, 67% to 85% and 93% to 98% of their active ingredient after 0.5, 4 and 12 hours, respectively. The relative standard deviations between the replicates from each batch were less than 10% for most time points. The percent of drug released over the first 4 hours was linear (r squared = 0.9409-0.9999) when plotted versus time 1/2, indicating adherence to the simplified Higuchi model. Statistical analysis of the Higuchi dissolution constants indicated a significant difference (P less than 0.05) between batch No.3 and the other two batches of 200-mg oxycodone hydrochloride capsules. There was also a statistical difference between most of the Higuchi dissolution constants for the different-strength slow-release capsules and most slow-release capsules and equivalent strength controlled-release manufactured tablets (P less than 0.05). Using 40% Methocel E4M Premium slowed the release of morphine sulfate and oxycodone hydrochloride from extemporaneously compounded capsules. The in vitro performance of the slow-release capsules showed little intrabatch variation, and only one preparation showed statistically significant interbatch variation, indicating reproducible and robust formulation. Even though changing the quantity of the formulation ingredients altered the release characteristics of the slow-release capsules, which also varied from that of equivalent strength-controlled release tablets, their release profiles were similar. Further testing is needed to determine whether these diffences are clinically significant.