Ali Rafal S, Al-Sudani Hussein, Tan Irene J
Internal Medicine, Einstein Medical Center Montgomery, East Norriton, USA.
Rheumatology, Einstein Medical Center Philadelphia, Philadelphia, USA.
Cureus. 2022 Mar 1;14(3):e22735. doi: 10.7759/cureus.22735. eCollection 2022 Mar.
Corticosteroid therapy is a known risk factor for osteonecrosis, more commonly with chronic use and high cumulative dose. Osteonecrosis (avascular necrosis) has been described in pregnancy involving primarily the femoral head. To our knowledge, only rare cases of femoral meta diaphysis or knee osteonecrosis in pregnancy have been documented in the literature. We report a 28-year-old woman with sickle cell trait and beta-thalassemia trait who developed severe bilateral knee pain shortly after corticosteroid therapy. She was 34-weeks pregnant when she presented with the signs of preterm labor and was found to have oligohydramnios and preeclampsia. She was given two intramuscular injections of betamethasone 12 mg one day apart to enhance the fetal lung maturity. Within hours of the second injection, she developed acute and severe bilateral knee pain affecting her mobility and ambulation. Bilateral knee x-rays were unremarkable. Given the severity and persistence of her pain, magnetic resonance imaging (MRI) of bilateral lower extremities was done few days later and showed signs of early osteonecrosis involving bilateral distal femoral meta diaphysis and right lateral femoral condyle. Other than the steroid therapy she had received, no additional extrinsic risk factors for osteonecrosis were identified. Potential intrinsic risk factors were thought to include her combined sickle-beta-thalassemia traits and pregnancy. She was diagnosed with steroid-induced osteonecrosis, given the temporal relationship. Her presentation was unique, because osteonecrosis affected unreported sites during pregnancy, and it started shortly after a brief course of antenatal steroid. She was treated conservatively with analgesics, and outpatient orthopedic follow-up was recommended. She was advised to avoid prolonged weight-bearing and strenuous activities. On a follow-up appointment two months later, she was still complaining of bilateral knee pain with ambulation though it was less severe. She did not return for follow-up thereafter. We suggest the possibility of osteonecrosis in pregnancy involving uncommon sites, such as distal femur and femoral condyle in this case, following one or two doses of systemic steroid. Obstetricians need to consider osteonecrosis when evaluating an unexplained musculoskeletal pain after betamethasone that is used for preterm labors. More studies, including reporting more cases with unusual presentation and prospective studies following pregnant patients receiving steroid therapy, are needed to better understand the causes, associations, management, and clinical course of osteonecrosis in pregnancy.
皮质类固醇疗法是已知的骨坏死危险因素，长期使用且累积剂量高时更常见。文献中已描述妊娠期间发生的骨坏死（缺血性坏死）主要累及股骨头。据我们所知，文献中仅记载了妊娠期间罕见的股骨干骺端或膝关节骨坏死病例。我们报告一名患有镰状细胞性状和β地中海贫血性状的28岁女性，在接受皮质类固醇治疗后不久出现严重的双侧膝关节疼痛。她在孕34周时出现早产迹象，被发现羊水过少和子痫前期。为促进胎儿肺成熟，她在一天内分两次接受了12毫克倍他米松的肌肉注射。在第二次注射后的数小时内，她出现急性且严重的双侧膝关节疼痛，影响了她的活动和行走能力。双侧膝关节X线检查未见异常。鉴于她疼痛的严重程度和持续性，数天后对双侧下肢进行了磁共振成像（MRI）检查，结果显示早期骨坏死迹象，累及双侧股骨远端干骺端和右侧股骨外侧髁。除了她接受的类固醇治疗外，未发现其他额外的骨坏死外在危险因素。潜在的内在危险因素被认为包括她的镰状-β地中海贫血复合性状和妊娠。鉴于时间关系，她被诊断为类固醇诱导的骨坏死。她的表现很独特，因为骨坏死在妊娠期间累及了未报道的部位，并且在短期的产前类固醇治疗后不久就开始了。她接受了镇痛药保守治疗，并建议进行门诊骨科随访。建议她避免长时间负重和剧烈活动。在两个月后的随访预约中，她仍诉说行走时双侧膝关节疼痛，尽管疼痛程度减轻了。此后她未再回来随访。我们认为在妊娠期间，在接受一或两剂全身类固醇后，有可能发生骨坏死累及不常见部位，如本例中的股骨远端和股骨髁。产科医生在评估用于早产的倍他米松治疗后不明原因的肌肉骨骼疼痛时需要考虑骨坏死。需要更多的研究，包括报告更多表现不寻常的病例以及对接受类固醇治疗的孕妇进行前瞻性研究，以更好地了解妊娠期间骨坏死的病因、关联因素、管理和临床过程。
