Painful snapping of the scapula may have an anatomical cause but is usually idiopathic. Most patients respond well to conservative measures such as physiotherapy or non-steroidal anti-inflammatory drugs. Surgery can be performed if conservative treatment is unsuccessful. Conservative measures are less likely to be successful if a clear anatomical cause can be found. Several surgical techniques have been described, ranging from bursectomy to resection of the lesion or of part of the scapula. The lesion is usually resected by an open technique. Scapulothoracic arthroscopy has previously been shown to be a safe procedure with low morbidity in idiopathic cases. A case is described in which painful crepitus of the scapula not responding to conservative measures was caused by an inferior subscapular osteochondroma. Arthroscopic resection of the osteochondroma was performed using a custom, lesion specific, inferior portal. This resulted in restoration of a full and painless function of the shoulder within two weeks of surgery.