Limb length deficiency, secondary to trauma or infection, is a common reason for referral to our tertiary service. After experiencing troubles with the Intramedullary Skeletal Kinetic Distractor (ISKD), we changed implant to the magnet operated Precice nail. We evaluated the safety and reliability of this novel device and compared it to our early ISKD results.

To minimise variables, we selected femurs only. In total, we reviewed medical and radiographic records of 20 cases (8 ISKD, 12 Precise) from 2010–2015. At each postoperative visit, the accuracy and precision of distraction and complications were recorded. Accuracy reflected how close the measured lengthening was to the prescribed distraction at each postoperative visit. Precision reflected how close the repeated measurements were to each other over the course of total lengthening period. No patients were lost to follow-up (1–3.5 years).

With the Precice nail (2012–2015), 11/12 were male and 10/12 were caused by trauma. The mean age was 34. Mean total lengthening was 38mm (range, 29–53mm), with an accuracy of 98percnt; and precision of 92percnt;. All patients achieved target lengthening at a rate of 1mm lengthening per day. In one case, the Precice nail fractured and this was revised successfully. With the ISKD group (2010–2012), 8/8 had complications (magnet jamming, nail breakage, equinus contractures and claw toes), with 25percnt; achieving accurate lengthening and precision of 38percnt;.

Our results so far have justified our change in implant choice and, in our experience, support the Precice nail as being safe and precise.

Background:

External fixators are not as well tolerated around the femur when compared to the tibia. Lengthening with an intramedullary device is therefore attractive.