Necrosis in the flexor hallucis longus muscle after subclinical leg compartment syndrome and tibial fracture: A case report

INTRODUCTION: Compartment syndrome is a condition in which an increased pressure within one compartment results in decreased blood flow, preventing nutrition and blood supply from reaching nerve and muscle cells. Ongoing physiological cascades can progress to local and systemic manifestations. This article presents a case of subclinical compartment syndrome resulting in muscle necrosis and contracture. More specifically, this article highlights the presentation of a complicated and neglected case of subclinical compartment syndrome with a subsequent fixed equinus deformity and its management. PRESENTATION OF CASE: A 15-year-old high school student sustained a proximal tibia fracture during a motor vehicle accident. The compartment was not recognized until a period of follow-up. The patient later presented to our clinic with ankle equinus deformity. Further exploration found the contracture and necrosis of flexor hallucis longus (FHL) muscle. We excised the necrotic wound and performed an ankle fusion. DISCUSSION: The patient had developed subclinical localized deep posterior compartment syndrome in the distal portion of the FHL muscle. As only a small portion of the muscle was involved, there was no retraction of the main muscle belly; however, the necrotic part can become fibrotic and adhere to the surrounding tissues. While subclinical compartment syndrome is not uncommon, the finding of isolated FHL muscle necrosis is rare. Thus, the management is still debatable. CONCLUSION: This article emphasized that neglecting compartment syndrome may result in undesired complications, which emphasizes the importance of an early diagnosis and treatment.