Transient Osteoporosis

Background: Transient osteoporosis is an uncommon and self-limited clinical syndrome characterized by acute joint pain with evidence of bone marrow edema on MRI. It predominantly affects healthy middle-aged men or women in the third trimester of pregnancy. The hips, knee, foot and ankle are affected in decreasing order of frequency. Pathophysiology is unknown but multiple etiologies such as ischemia, neurogenic compression or impaired venous return have been proposed. Classically, it is unilateral and bilateral in only 20%-40% of cases. It has been reported to periodically involve different joints over time with one report showing the progression to regional migratory osteoporosis in at least 20% of patients. There are no specific biomarkers to aid with diagnosis, MRI shows diffuse bone marrow edema sometimes associated with joint effusion with infrequent subchondral microfractures. Other etiologies to consider for bone marrow edema include osteomyelitis, avascular necrosis, trauma, tumors and inflammatory arthropathy. Transient osteoporosis can be self- limiting however, bisphosphonate use has been associated with shortened recovery time. In our patient given lack of access to his previous records to review and ascertain his previous diagnosis, his diagnosis of record was transient osteoporosis rather than regional migratory osteoporosis. Clinical Case: A 47 yo male presented to clinic with complaint of left ankle pain. Pain initially noted when he tripped and fell one year ago. Initial x-rays did not reveal any fractures. He was unable to weight bear due to pain although he had full range of motion at the ankle with a normal neurological and vascular exam of the foot. Due to persistence of pain, an MRI was done which showed cutaneous edema around the medial and lateral aspects of the ankle, trace tibiotalar joint effusion, marrow edema in the distal tibia and navicular with no acute fracture or definite evidence of avascular necrosis. On further questioning he reported a previous history of hip pain at age 32 and 41 with no preceding trauma. X-rays were negative for fracture and MRI showed marrow edema. Symptoms resolved after a few weeks with possible treatment with Alendronate. With the current presentation biochemical work up including Vitamin D, PTH, 24-hour urine calcium, electrolytes, phosphorus and alkaline phosphatase was unremarkable. Given the marrow edema reported on MRI, absence of fracture, osteochondral lesion or recent trauma transient osteoporosis was diagnosed. Given the duration of symptoms he was treated with Reclast 5mg IV once and reported 80% improvement in ankle pain during follow up 4 weeks later. Conclusion: It is important to identify transient osteoporosis and regional migratory osteoporosis to prevent unnecessary medical or surgical therapy.

THU0463 EFFICACY AND SAFETY OF NERIDRONATE IN BONE EDEMA SYNDROME

Background:Bone Marrow Edema Syndrome (BMES) is a severely disabling pain syndrome without a definite treatment and refers to transient clinical conditions with unknown pathogenic mechanism, such as transient osteoporosis of the hip (TOH), regional migratory osteoporosis (RMO), and reflex sympathetic dystrophy (RSD). Magnetic resonance imaging is used for the early diagnosis and monitoring the progression of the disease. Early differentiation from other aggressive conditions with long-term sequelae is essential in order to avoid unnecessary treatment.Objectives:Aim of this monocentric trial was to test the efficacy and the safety of the amino-bisphosphonate neridronate in patients with BMES administered in two different regimens.Methods:192 patients with BMES secondary to osteoarthritis localized to knee, hip, wrist or foot were randomly assigned to I.V. infusion of 100 mg neridronate given four times over 10 days (Group A, 72 subjects) or alternatively to I.V. infusions of 100 mg every 21 days over 3 months (Group B, 120 subjects). At baseline and after 180 days we performed an MRI. We assessed a 0-100 mm pain VAS in each patient, too. Outcomes were to evaluate the MRI changes and the VAS changes. A control group (35 patients) was enrolled too, treated conservatively with NSAIDs and articular rest.Results:we observed a significant improvement in MRI with the resolution of bone marrow lesions present at the baseline (p<0.01), without a significant difference between Group A and Group B. Visual analogue scale (VAS) score decreased significantly during the study in both groups (p<0.05) without a significant difference between the two treatment groups (p>0.1). Both groups showed a significant clinical and radiologic improvement compared with control group (p<0.001).Conclusion:In patients with BMES, the infusions of neridronate 100 mg every 21 days over 3 months or alternately every 3 days over 10 days are associated with clinically relevant and persistent benefits without significant differences between the two treatment-schedules. These results provide conclusive evidence that the use of bisphosphonates, at appropriate doses, is the treatment of choice BMES.Disclosure of Interests: :None declared

Knochenmarködemsyndrome

ZusammenfassungSeit 1959 die ersten Fälle einer transienten Osteoporose beschrieben wurden, gibt es eine Vielzahl an Literaturberichten über das Knochenmarködemsyndrom (KMÖS). Trotz der immer besseren Bildtechnologien bleibt die richtige Diagnosestellung bei Vorliegen eines Knochenmarködems immer noch eine Herausforderung. Eine regionale radiologische Knochendichteminderung zusammen mit einem Knochenmarködem kann bei mehreren KMÖS, wie z. B. der transienten Osteo- porose oder der “regional migratory osteoporosis”, beobachtet werden. Zudem ähneln sich die Erkrankungen in der klinischen Beschwerdesymptomatik mit selbstlimitierendem Verlauf. Jedoch ist die Differenzierung zu anderen aggressiven Erkrankungen mit möglichen Langzeitfolgen für eine korrekte Therapie essenziell. Der Pathomechanismus dieser Erkrankungen ist weiterhin ungeklärt und ist genauso wie verschiedene Therapieformen Gegenstand aktueller Studien.