This cat has a developmental anomaly called the Manx cat syndrome. Manx cats with less than 3 coccygeal vertebrae (called rumpies) may have incomplete development of the nerves arising from sacral segments S1-S3 and coccygeal segments. The pelvic, pudendal and sciatic nerves may be affected. In this case, primarily pudendal nerve. There is one coccygeal vertebra and fusion of L7 to the sacrum. These are common radiographic lesions of the Manx cat syndrome. The vertebral lesions do not cause the clinical signs so surgery is not beneficial. There is no treatment.