Unique case of intraperitoneal loss of pelvic array pin in setting of routine navigated total hip arthroplasty

Pelvic array pin placement during navigated total hip arthroplasty has been known to cause complications; however, most of them are minor. While intraoperative pin migration has been documented as a complication, a complete loss of the iliac array pin within the peritoneum has not been reported in literature.

Heng Kan et al described a case of 78-year-old female who underwent a routine computer-navigated total hip arthroplasty for the indication of severe osteoarthritis. The Intellijoint HIP approach platform was used with the standard workflow whereby iliac array pins were inserted percutaneously through a stab incision prior to primary incision. The 6.5-mm self-tapping navigation pin was inserted as per surgical technique recommended by the manufacturer. Surgical landmarks were referenced at the apex of the iliac wing between the anterior superior iliac spine and posterior inferior iliac spine. The pins are then inserted 1 cm distal to that point to ensure sufficient circumferential bone stock. Upon attachment of the handheld screwdriver to advance the pin, a sudden loss of purchase was encountered whereby the shaft of the screwdriver, including the pin attached, plunged into the pelvis leading to the loss of the pin.

On-table retrieval was attempted by taking down the external oblique attachment to the iliac crest to gain access to the medial side, but the pin was unable to be located. An intraoperative x-ray was performed to demonstrate an intrapelvic position. The primary total hip arthroplasty was abandoned.

As the surgery was performed in a peripheral metropolitan center, initially an on-table general surgical opinion was obtained. Given the position of the pin to the iliac vessels, a vascular opinion was also acquired from the nearby tertiary center. On-table clinical examination revealed a hemodynamically stable patient with strong bounding pedal pulses bilaterally. A computed tomography angiogram was performed displaying the pin’s proximity to the right common iliac artery. Examining the bony details, there was no evidence of fracture, incorrect entry point, or skiving of the pin. Instead, the image revealed a circular hole just bigger than the diameter of the pin. The patient was kept anesthetized to mitigate any further harm from patient movement while the screw remained within the pelvis, and she was immediately transferred to the tertiary center 20 minutes away.