Intramuscular myxoid lipoma in the proximal forearm presenting as an olecranon mass with superficial radial nerve palsy: a case report

Endoscopic En-Bloc Resection of Intra-Muscular Lipoma of the Flexor Digitorum Profundus: A Uniportal Technique

Deep-seated lipomas can be intramuscular, intermuscular, and rarely, parosteal lipomas. Intramuscular lipoma can be divided into infiltrative, well-circumscribed, and mixed types. Marginal excision is the treatment of choice for well-circumscribed intramuscular lipoma, and histopathology eliminates diagnosis of well-differentiated liposarcoma. The purpose of this technical note is to describe the details of endoscopic en-bloc resection of intramuscular lipoma of the flexor digitorum profundus. This minimally invasive approach allows en-bloc resection of the lipoma for histopathological study, with minimal risk to the surrounding neurovascular structures.

Distribution of intramuscular giant lipomas in the functional compartments of the forearm: a report of 12 cases

PURPOSE

The aim of this study was to investigate the distribution of intramuscular giant lipomas in the functional compartments of the forearm and to compare their clinical, radiological and histopathological features with those reported in the current literature.

METHODS

The study included 12 patients who were surgically treated for intramuscular lipomas > 5 cm in size located in the forearm that had been confirmed histopathologically between April 2006 and March 2017. Data about the patients with respect to age, sex, affected side, localisation of the lipomas in the forearm functional compartments, size, histopathological features and recurrence were collected. According to the clinical complaints, direct radiography and magnetic resonance imaging were applied.

RESULTS

The average diameter was 6.5 cm (range: 5.5-9 cm). All lipomas had a well-defined border. All the patients presented with soft-tissue masses that were painless in seven patients. Five patients had nerve compression symptoms. When the lipomas were classified according to the functional compartments of the forearm, six of them were located in the superficial volar compartment, two in the deep volar compartment, two in the deep dorsal compartment and two in the lateral compartment. All lipomas were surgically removed by marginal excision. None had complications or recurrence at a mean of 6.5 years follow-up (range: 1-12 years) after surgery.

CONCLUSIONS

Intramuscular lipoma is a relatively uncommon tumour, especially in the forearm. Because of the proximity to the neurovascular structures in the forearm, excision of lipomas should be performed with care and include wide incisions. Additionally, knowing the anatomical features of the compartment where the lipoma is localised in the forearm is important in planning surgery to enable easier dissection of the lipoma and lessen the risk of damage to adjacent neurovascular structures.

LEVEL OF EVIDENCE

Level 4.

[Intramuscular lipomas: Large and deep benign lumps not to underestimated. Review of a series of 51 cases]

OBJECTIVE

To review a poorly studied pathology in the scientific literature.

MATERIAL AND METHODS

An observational, longitudinal and ambispective study of a series of 51 intramuscular lipomas in 50 patients. The frequency distribution of qualitative variables, and the median and the interquartile range (IQR) for continuous variables were calculated. The relationship between the size of the lipomas (recoded into two values) and the study variables were analyzed using the Fisher exact test.

RESULTS

Men made up 62% of the series, and the median age was 61 years, with 55% of the total being overweight. About half of the patients were diagnosed in the upper limb. More than three-quarters (78%) were strictly intramuscular lipomas. Location, clinical and image presentation, treatment and results are described.

DISCUSSION

Intramuscular lipomas have their own particular characteristics. Nevertheless, MRI is sometimes unable to distinguish them from well differentiated liposarcomas. Using size as the only criterion for referring a patient with a soft tissue injury to a reference center is still debatable.

CONCLUSIONS

Patients with intramuscular lipomas, although they may be typical in their presentation, especially when they are large and show findings that can be confused with a well-differentiated low grade liposarcoma, should be treated in experienced centers.