eCommons@AKU Section of Orthopaedic Surgery Department of Surgery 2018 Osteoid osteoma: Contemporary management Shahryar Noordin Aga Khan University, [email protected] Salim Allana Emory University Kiran Hilal Aga Khan University, [email protected] Riaz Hussain Lukhadwala Aga Khan University, [email protected] Anum Sadruddin Pidani Aga Khan University, [email protected] See next page for additional authors Follow this and additional works at: https://ecommons.aku.edu/pakistan_fhs_mc_surg_orthop Part of the Orthopedics Commons, Radiology Commons, and the Surgery Commons Recommended Citation Noordin, S., Allana, S., Hilal, K., Lukhadwala, R. H., Pidani, A. S., Ud Din, N. (2018). Osteoid osteoma: Contemporary management. Orthopedic Reviews, 10(3), 108-119. Available at: https://ecommons.aku.edu/pakistan_fhs_mc_surg_orthop/92 Authors Shahryar Noordin, Salim Allana, Kiran Hilal, Riaz Hussain Lukhadwala, Anum Sadruddin Pidani, and Nasir Ud Din This article is available at eCommons@AKU: https://ecommons.aku.edu/pakistan_fhs_mc_surg_orthop/92 Orthopedic Reviews 2018; volume 10:7496 Osteoid osteoma: Contemporary management Epidemiology Correspondence: Shahryar Noordin, Orthopaedic Surgery, Aga Khan University, Osteoid osteoma accounts for around Karachi, Pakistan. Shahryar Noordin,1 Salim Allana,2 5% of all bone tumors and 11% of benign Tel.: 021.3486.4384. 4 Kiran Hilal,3 Naila Nadeem,3 bone tumors. Osteoid osteoma is the third E-mail: [email protected] Riaz Lakdawala,1 Anum Sadruddin,4 most common biopsy analyzed benign bone 5 tumor after osteochondroma and nonossify- Key words: Osteoid osteoma; tumor; benign; Nasir Uddin imaging; pathogenesis; management. 1 ing fibroma. Two to 3% of excised primary Orthopaedic Surgery, Aga Khan bone tumors are osteoid osteomas.5 Males University, Karachi, Pakistan; Contributions: SN, SA, study design, data col- are more commonly affected with an lection, manuscript writing; KH, NU, data col- 2 5 Department of Epidemiology, Rollins approximate male/female ratio of 2 to 1. lection, manuscript writing; NN, RL, AS, School of Public Health, Emory Adolescents and young adults are usually study design, manuscript writing. University, Atlanta, GA, USA; affected in the second decade of life, with 3Department of Radiology, Aga Khan most patients being under the age of 20 Conflict of interest: the authors declare no University, Karachi, Pakistan; years. It is less likely to be seen in patients conflicts of interests. 4Department of Surgery, Aga Khan under 5 years of age or in adults greater than 4 Received for publication: 15 November 2017. University, Karachi, Pakistan; 40 years. Revision received: 6 March 20018. 5Department of Pathology and Accepted for publication: 18 March 2018. Laboratory Medicine, Aga Khan University, Karachi, Pakistan This work is licensed under a Creative Localisation Commons Attribution NonCommercial 4.0 License (CC BY-NC 4.0). Osteoid osteoma occurs predominantly ©Copyright S. Noordin et al., 2018 Abstract in the appendicular skeleton. Spine is involved in one tenth of the cases.6 Flat Licensee PAGEPress, Italy Orthopedic Reviews 2018;10:7496 Osteoid osteoma is a benign bone-form- bones with intramembraneous formation in doi:10.4081/or.2018.7496 ing tumor with hallmark of tumor cells direct- the body and skull are rarely affected. The ly forming mature bone. Osteoid osteoma lower extremity is more commonly affected accounts for around 5% of all bone tumors than the upper extremity as shown in Figure and 11% of benign bone tumors with a male 1. Commonly long bones particularly the predilection. It occurs predominantly in long femur and tibia are involved, followed far increasingly severe at night and usually bones of the appendicular skeleton. behind by bones of the feet, with a predilec- responds to salicyclates and non-steroidal According to Musculoskeletal Tumor Society tion for the talar neck. Common sites of anti-inflammatory medications. If osteoid staging system for benign tumors, osteoid femoral involvement are the juxta- or intra- osteoma involves a bone in a subcutaneous osteoma is a stage-2 lesion. It is classified articular regions of the femoral neck. In the location, then the patient usually presents based on location as cortical, cancellous, or upper extremity, phalanges of the hand are with swelling, erythema and tenderness. subperiosteal. Nocturnal pain is the most commonly affected.4 If the proximal femur or pelvis is common symptom that usually responds to involved, the patient can present with salicyclates and non-steroidal anti-inflamma- referred pain in the knee. Lesions that are tory medications. CT is the modality of within the joint or juxta-articular can pres- choice not only for diagnosis but also for Classification ent with synovitis. If this continues to specifying location of the lesion, i.e. cortical progress, the patient can present with joint vs sub periosteal or medullary. Non-operative In long bones, osteoid osteoma is more pain, flexion contracture, decreased range treatment can be considered as an option often situated in the cortico-diaphyseal or of motion, and a limp or antalgic gait. since the natural history of osteoid osteoma is metaphyseal regions, but other localizations Sometimes in children, a limp may be the that of spontaneous healing. Surgical treat- such as intramedullary, subperiosteal, epi- only presenting symptom. If the lesion ment is an option for patients with severe pain physeal or apophyseal have also been involves the open physis, it can result in and those not responding to NSAIDs. noted.6 It is very rare to have two osteoid limb length discrepancy with potential Available surgical procedures include osteomas in the same patient.4 coronal and/or sagittal malalignment. radiofrequency (RF) ablation, CT-guided per- According to Musculoskeletal Tumor Referred pain and muscle atrophy can cutaneous excision and en bloc resection. Society staging system for benign tumors, result in misdiagnosis of a neurological dis- osteoid osteoma is a stage-2 lesion. It is order commonly seen in axial skeleton classified as cortical, cancellous, or subpe- involvement with postural scoliosis due to riosteal. Cortical lesions are most common.4 paravertebral muscle spasm, which is Introduction reversible after treatment.7 Osteoid osteoma is a benign bone-form- ing tumor with hallmark of tumor cells 1 Clinical presentation directly forming mature bone. These are Pathogenesis small, distinctive, nonprogressive, benign Pain is the most common symptom. osteoblastic lesions. Bergstrand first Usually it is a dull ache, which is unremit- The exact pathogenesis of osteoid described osteoid osteoma in 1930 and Jaffe ting and starts off as mild and intermittent osteoma remains unknown. High levels of in 1935 characterized it as a benign that gradually increases in intensity and per- prostaglandin E2 and prostacyclin have osteoblastic tumor.2,3 sistence. The pain has a tendency to become been found within the nidus that is believed [page 108] [Orthopedic Reviews 2018; 10:7496] Review to cause local inflammation and vasodilata- fresh, and brown to granular after formalin ally thin and short, but can be sclerotic and tion. A study by Mungo et al.8 revealed fixation. They are well demarcated from the broad and are rimmed by a single layer of increased levels of cyclooxygenase-2 surrounding white sclerotic cortical bone. osteoblasts. Scattered osteoclasts are also expression in nidus osteoblasts. The nidus color is related to vascularity of present on the surface of bony trabeculae Cyclooxygenase-2 inhibition is believed to intertrabecular areas. As osteoid osteomas (Figure 2). The osteoblasts are plump, uni- be a mechanism by which NSAIDs provide are now treated by radiofrequency ablation, form in size and shape and have eccentric symptomatic relief in osteoid osteomas. such intact specimens as described above nuclei with small nucleoli and open chro- 12 These inflammatory mediators may also are rarely received for histopathology. matin. Cytoplasm is usually amphophilic. contribute to perilesional sclerosis exhibited No nuclear pleomorphism or increased by most osteoid osteomas. In addition, high mitotic activity is seen. The intertrabecular concentrations of intralesional unmyelinat- stroma is loose and fibrovascular (Figure 3). ed nerve fibers have been implicated in the Microscopic features The reactive bone surrounding the nidus is pathogenesis of the exquisite nocturnal dense cortical or trabecular bone and when Histologically, the nidus is well circum- pain. These processes probably function in the tumor grows closer to the bone surface, scribed and composed of haphazardly inter- it becomes more pronounced. In medullary parallel to produce the characteristic 13 9,10 anastomosing trabeculae of variably miner- lesions, it is less pronounced. inflammatory symptoms. alized woven bone. The trabeculae are usu- Historically, there has been debate over The pathologic evaluation of osteoid the years about the precise nature of osteoid osteomas. Initially considered a neoplasm by Jaffe, other investigators proposed a reactive or reparative process citing its lim- ited growth potential and its ability to spon- taneously regress in some cases.2 Currently, most pathologists agree about the neoplastic nature of osteoid osteomas. The tumour’s histological similarity to osteoblastoma supports the belief that it is a benign tumour derived from the osteoblasts. There have been few cytogenetic studies that reported clonal cytogenetic abnormalities,