Related Experiment Video
Updated: Feb 23, 2026
Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children
Published on: September 11, 2018
Detection of Retained Foreign Objects in Upper Extremity Surgical Procedures With Incisions of Two Centimeters or
Josef N Tofte1, Lindsey S Caldwell1
1University of Iowa Hospitals and Clinics Department of Orthopaedics and Rehabilitation.
Background:
While the true incidence of retained foreign bodies after surgery is unknown, it has been approximated at 1:5,500 operations overall, with substantially less frequency in hand and upper extremity procedures. Despite the rarity of foreign body retention in hand and upper extremity surgery, universal radiofrequency scanning for electronically-tagged sponges and automatic radiographic evaluation for incorrect sponge counts are employed for all surgical procedures at our institution. We demonstrate the infeasibility of retaining an operative sponge of a standard size in commonly performed hand and upper extremity procedures with incision sizes of two centimeters or less, and establish that visual detection of sponges in these cases is adequate.
Methods:
Eighteen trigger finger releases, five carpal tunnel releases, three trigger thumb releases, and three de Quervain's tenosynovitis releases were successfully performed upon five cadaveric specimens by residents under supervision of fellowship-trained hand surgeons for a total of 29 two-centimeter or smaller incisions. Randomized surgical sponge placement was evaluated by a blinded observer at two distances and incision sizes were quantified. Kappa values were calculated to determine the acuity of visual detection versus the actual presence of a sponge.
Results:
The maximum length of the standard surgical sponge that could be contained within an incision was three centimeters. When compared with the gold standard (whether the sponge had been placed or not by the operating resident), the placement of a standard surgical sponge could be detected correctly in 100% of cases at both "across the room" and "at the table" distances, for kappa values of 1.0 and 1.0 respectively. This did not vary with incision size or surgical procedure.
Conclusions:
The added cost and time from radiofrequency detection of retained sponges and radiographic evaluation in the event of incorrect sponge counts can be safely eliminated if sponges can be reliably visually detected.
Clinical Relevance:
This cadaveric study informs patient safety practices by demonstrating that visual detection of surgical sponges is adequate for certain upper extremity procedures.
