Introduction Trigger finger is a rare entity in children and synovial chondromatosis is a rare cause of trigger finger in all patient groups. This is the first documented case of tenosynovial chondromatosis in the paediatric population and a review of the available literature regarding this condition. Case 16-year-old boy presented with variable and intermittent locking associated with pain in the left small finger and pain at the A1 pulley. High-resolution ultrasound revealed multiple echogenic ossified bodies within the distal flexor sheath of the A1 pulley. Explorative surgery revealed that these ossified bodies, at the level of Camper’s chiasm, herniated through the flexor sheath with passive flexion. These lesions were removed and the flexor sheath repaired. The patient was commenced on an immediate active and passive exercise program and recovered with no complications. Histopathology from the intra-operative samples collected showed a well-circumscribed osteochondroid lesion, consistent with a focus of synovial osteochondromatosis. Conclusion This case describes a rare condition in the paediatric population and the first to date. There are multiple possible causes of paediatric trigger finger and whilst tenosynovial chondromatosis is not the most common differential, this case demonstrates the importance of a thorough clinical assessment and judicious use of imaging prior to proceeding to surgery. This approach to trigger finger in both paediatric and adult patients improves surgical planning and contributes to positive functional outcomes, such as the resolution of symptoms as described for this young patient.