Painful Intramuscular Lipoma of the Infraspinatus: Unusual Location and Presentation

Abstract

1 and found it instructive for clinical practice. The authors presented a fascinating case of intramuscular lipoma located in the infraspinatus muscle and presenting with pain. The patient reported shoulder pain and deficit in joint mobility. The diagnosis was made with the use of ultrasound. Finally, after surgical excision, the patient had complete relief of pain and complete recovery of range of motion.This report was informative, detailing the specific features of the case and the diagnostic path followed by the authors. The location of this lipoma was unusual, which added value to this report. Moreover, clinical evaluation was performed and was completed with the use of instrumental diagnostic tools, in particular ultrasound. The lesion was detected by ultrasound; magnetic resonance imaging had only confirmed the presence of intramuscular alteration. Ultrasound served as an extension of the physical and visual examination.2 A lipoma with a deep localization, as in this case, is not accessible via simple palpation; hence, investigation using instrumentation is mandatory. In some cases, ultrasound is the best choice because it is less expensive and easier to perform than magnetic resonance imaging. In addition, in this case, ultrasound was necessary for successful surgery, as an accurate morphologic evaluation is needed to determine the surgical approach and avoid possible side effects of the intervention.On the basis of our experience, ultrasound plays a crucial role in orthopedics, neurology, and rehabilitation.3 In addition to evaluating the muscles, ultrasound offers the possibility of widely and precisely studying the nerves, permitting assessment of patients' condition and providing important data about diagnosis, prognosis, and therapy in cases of peripheral neuropathies.

Anatomical Distribution of Intramuscular Lipomas

“…The biceps brachii [59], the subscapularis [60], the deltoid [61][62][63], the supraspinatous [64,65], the infraspinatus [66] and the brachioradialis [67] may be involved, while localization adjacent to the proximal radius may be complicated by symptomatic radial nerve compression [68][69][70]. Involvement of the tensor fascia lata has also been reported [71] as well as of the vastus lateralis [51] and of the gluteus maximus and gastrocnemius [14].…”