Background: Intramuscular venous malformations, often erroneously called "intramuscular hemangiomas," present to pediatric orthopaedic surgeons either as a differential diagnosis of tumor or as a cause of muscle pain. Treatment options include injection sclerotherapy or surgery. There is some literature to indicate that sclerotherapy can reduce pain, but little evidence on the effectiveness of surgery. The primary aim of this study was to evaluate the efficacy of surgical resection for intramuscular venous malformations, with a secondary aim to evaluate the natural history and presentation of intramuscular venous malformations to improve clinician understanding of this condition.
Methods: A retrospective chart analysis was performed of cases identified from a vascular anomalies database from January 2004 and December 2018. Primary outcome was change in preoperative and postoperative pain. Natural history of the lesion was assessed, including age when the lesion was first noticed, when it became painful, and when it required treatment.
Results: Fifty-four cases were identified in the study period of which 40 underwent surgery. Pain improved in 36 of 39 patients (92.3%) who had pain before surgery and 29 (74.4%) were pain free after surgery. All 13 patients who required whole muscle excision to resect the lesion experienced an improvement in pain and 10 (76.9%) were pain free. A history of previous intervention, with surgery or sclerotherapy showed a trend towards less successful surgical outcomes. Patients presented across a wide age range from infancy to adulthood, but the most common presentation was pain with exercise between 9 and 16 years of age, with presence of a mass in about half of cases.
Conclusions: Surgery, when performed by a surgeon with appropriate experience, is an effective first-line treatment for painful intramuscular venous malformations, offering pain relief in the majority of cases. Magnetic resonance imaging and ultrasound are diagnostic in most cases. The majority of lesions are resectable, meaning they can be removed with a margin leaving a functional limb. Sometimes resection of a whole muscle is required.
Level of evidence: Level IV-case series.