A 10-year-old boy with a history of two and a half years of low back pain was referred for a bone scan. Symptoms were more troublesome at night than during the day and had worsened in the previous few months. The boy was otherwise well, and had not lost weight. Radiographs were normal, and bone scan with SPECT showed a focal area of increased tracer uptake in the lumbar spine on the right side of L4, which on SPECT imaging was shown to be in the posterior elements posterolaterally. CT scan performed shortly following the bone scan showed an osteoid osteoma in the right L4 lamina. This case demonstrates that increased uptake in the posterior elements posterolaterally can be due to osteoid osteoma, which should be included in the differential diagnosis for abnormal activity in this area.