Histopathologic profile of bone and joint lesions in a tertiary health institution in Southeast Nigeria: A nine-year review

Background: The human skeletal system is composed of all the bones, joints, cartilage, ligaments, and tendons. The lesions of this system were thought to be uncommon in our environment and like lesions in any other part of the body are better managed when early presentations and correct diagnosis are made. The paucity of research on these lesions has prompted the need to study the topic. Aims: We aimed to study the bone and joint lesions, with a view to determining the most common types, the most involved sites of the body, the sex, and the age of presentations. Materials and Methods: This was a retrospective study carried out at the Histopathology Department of Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria, from 2011 to 2019. Results: Eighty-four cases of bone and joint lesions were diagnosed in the study period, and they had a slight male preponderance with a M: F ratio of 1.4:1 and a mean age of 38.7 ± 22.0 years. Nonneoplastic lesions were more common 58.3% (49/84) than neoplastic tumours 41.7% (35/84). Benign tumours were however more common 27.4% (23/84) than malignant tumours 14.3% (12/84). Nonneoplastic lesions and benign tumours were seen in the first and second decades of life while malignant tumours occurred in the third and fourth decades. Of the 84 lesions, 47 cases were bone lesions while 37 were joint lesions. Osteomyelitis was the most common nonneoplastic bone lesion (7/47; 14.9%) while osteochondroma and giant cell tumours were the most common and only benign bone tumours seen and accounted for 14.9% (7/47) of cases each. Metastatic bone diseases (5/47; 10.6%) and osteosarcoma (4/47; 8.5%) were the most common malignant bone tumours, with osteosarcoma being the most common primary bone malignant tumours (4/7; 57.1%). Ganglion cysts were the most common lesions in all accounting for 23.8% (20/84) and the most common nonneoplastic (20/49; 40.8%) and joint lesions (20/37; 54.1%). Nodular tenosynovitis was the most common benign joint tumour and accounted for 10.8% (4/37) of cases; there is no malignant joint tumour. Skull was the most common anatomic site for bone lesions while the humerus was the most common anatomic site for bone tumours whereas wrist was the most common site for joint lesions. Conclusion: Nonneoplastic bone and joint lesions were more common than neoplastic lesions in our environment, with ganglion cysts being the most common joint lesions while osteomyelitis, osteochondroma, and giant cell tumours were the most common bone lesions. There is no malignant joint tumour observed in this study.