More than 50 years after being bitten by a venomous snake, a woman developed a large mass in her lower leg, according to a new report of her case. 
 
 The 66-year-old woman in Thailand had been bitten by a Malayan pit viper, a venomous snake native to Southeast Asia, when she was 14. 
 
 The painless mass had become noticeable 10 years earlier, and on an X-ray it looked like an enlarged cavity wrapped in a tough, calcified membrane, resembling an eggshell. It ultimately grew so large that it broke through the woman's skin. Doctors surgically removed the mass, and the wound completely healed by one month after the surgery, they wrote in their report, published June 16 in the Journal of Medical Case Reports. 
 
 Such masses have rarely been reported following a snakebite, but they have been seen following other types of traumatic injury to muscles, according to the report's authors, who are researchers at the Prince of Songkla University in Thailand. [16 Oddest Medical Cases] 
 
 A calcified mass can form as muscle tissue starts to die after a crushing injury or disruption of the blood supply, usually in the lower leg, said Dr. Darren Fitzpatrick, an assistant professor of Radiology at Mount Sinai Medical Center in New York, who wasn't involved in the woman's case. 
 
 The result is usually a firm, hard, palpable mass that can be examined using X-ray or MRI scans. [Image of the mass] 
 
 "It's very common for it to be mistaken for a tumor, but usually, the imaging helps with the diagnosis," Fitzpatrick told Live Science. 
 
 In the case of this patient, doctors suspected that, because of the snakebite, the woman had developed a condition called compartment syndrome; the name refers to sections of muscle that are held together, along with nerves and blood vessels, by a tough tissue called the fascia, which does not stretch easily. 
 
 The woman's compartment syndrome had been left untreated, according to the report. 
 
 "Compartment syndrome usually happens below the knee," Fitzpatrick said. "You have a big group of muscles there, and they are in kind of a tight compartment. 
 
 "If the muscles start to swell from trauma or injury, they can run out of space, and that could result in compromised blood flow," he added. "That's certainly a very plausible reason as to why this could have happened in this case." 
 
 
 
 Editor's Note: This article was updated at 5:00 p.m. ET. It incorrectly referred to the snake as poisonous rather than venomous. 
 
 Email Bahar Gholipour. Follow LiveScience @livescience, Facebook & Google+. Originally published on Live Science. ||||| Calcific myonecrosis is a rare condition. This condition was first reported in two patients by Gallie and Thomson following Volkmann's ischemic contracture[1]. The exact pathophysiology of this condition is unknown. A patient with calcific myonecrosis usually has muscle necrosis that usually occurs following high-energy trauma or compartment syndrome especially in cases that have peripheral nerve injury[2, 3]. There were also reports in which this condition was found after repeated trauma during epileptic seizures[4] and patients with a history of dermatomyositis[5]. O'Keefe et al. suspected progressive enlargement happened from repeated intralesional hemorrhage[6]. 
 
 Calcific myonecrosis following snake bite is rarely reported. In the present study, the patient had a history of snake bite and the physical examination showed sequelae of untreated compartment syndrome. Compartment syndrome following snake bite has been reported[7]. The patient in this present study who had sequelae from compartment syndrome developed calcific myonecrosis. 
 
 The most common area of calcific myonecrosis is the anterolateral part of the leg[8, 9]. This condition is usually found at the anterior compartment of the leg followed by the lateral and deep posterior compartments[2, 3]. The location of disease in the present report was consistent with previous reports. However, calcified myonecrosis at other areas has also been reported such as at the forearm[10] and foot[11]. The onset of this condition usually presented in the sixth and seventh decades of life but there were reports which showed this disease could happen in a wide range of ages from the third decade to the seventh decade[10, 12]. The intervals from history taking of the injuries until the patients’ visits for treatment varied from 10 to 60 years according to reports[12]. 
 
 The clinical presentation of this condition was a gradually enlarging painless mass with occasional tenderness. A plain radiograph of the mass usually showed fusiform mass with longitudinal peripheral plaque-like calcification involving the entire compartment[2, 6]. Bone erosion could be found but the periosteal reaction was smooth[12]. In some cases cortical scalloping could happen due to the chronic pressure effect of the gradually enlarging mass. An MRI of the mass showed central liquefaction with homogeneous signal on T1-weighted and T2-weighted images and heterogeneous signal on T2-weighted image. T1- and T2-weighted images showed low signal at the peripheral calcification without enhancement after gadolinium injection[13]. However, Okada et al. reported one case in which MRI demonstrated peripheral ring enhancement on postcontrast fat-suppressed T1-weighted images[14]. 
 
 A differential diagnosis of this condition included soft tissue sarcoma and myositis ossificans. Soft tissue sarcoma with radiographic soft tissue calcification could be synovial sarcoma, epithelioid sarcoma or soft tissue osteosarcoma; soft tissue sarcoma has a more aggressive radiographic appearance than calcific myonecrosis and mineralization is usually distributed throughout the mass which is different from calcific myonecrosis which usually has peripheral calcification with central liquefaction[3]. Radiographic images of myositis ossificans usually show a central trabeculation and marrow signal in MRI without a history of progressive enlargement of the mass[11]. 
 
 A biopsy in calcific myonecrosis is not recommended due to the high risk of infection[2]. The infection could develop in cases as high as 30% after surgery[12]. However, there were some patients who had infection at the first presentation without any surgical interventions[11]. Prevention of this condition is early detection and treatment of patients who have compartment syndrome[15]. In an asymptomatic patient, a recent report suggested observation of the clinical symptoms and signs due to the benign nature of the disease to avoid complications from surgery which has a high rate of postoperative infection[2]. 
 
 In a symptomatic patient, complete mass excision with flap coverage and primary closure with a suction drain or open wound for secondary intentional healing were recommended[3, 11]. In the present study, we performed a primary closure and retained a prolonged vacuum drain for 12 days for seroma prevention by draining serous fluid from the dead space after mass excision. Postoperative antibiotics recommended in previous reports were combined with antibiotics that covered Gram-positive and Gram-negative microorganisms and then were adjusted based on the intraoperative culture. The antibiotics should be continued for 6 to 8 weeks[3, 8, 9].
– It was a slowww reaction. When she was 14, a girl in Thailand got bit in the leg by a poisonous snake called the Malayan pit viper. A half-century later, she showed up at the doctor with a painful mass in that same leg, reports LiveScience, picking up on a writeup in the Journal of Medical Case Reports. Doctors first diagnosed the mass as calcific myonecrosis, the result of the venom destroying muscle tissue, when the woman was 66. Five years later, the still-growing mass actually came through her skin, and doctors surgically removed it without further complications. (Click to read about the discovery of a snake long thought extinct.)