PRECICE vs. LON: How the Two Most Common Limb Lengthening Methods Compare

Short Answer

Titanium PRECICE IMLL is a fully internal magnetic lengthening nail. LON combines an intramedullary nail with an external fixator during distraction, then locks the nail and removes the frame for consolidation. Neither is universally superior; anatomy, indication, deformity, device fit, load needs, infection exposure, operations, rehabilitation, cost, and provider experience all matter. ^[1]

PRECICE IMLL

The nail is inserted in the medullary canal and locked proximally and distally at the initial operation. An external controller actuates distraction. There are no external pin sites, but the method still has incision, nerve, joint, regenerate, alignment, infection, implant, load, and reoperation risks.

LON

The frame supplies distraction while the nail is already present. At the transition after distraction, the nail is locked and the frame removed so the nail supports consolidation. Frame duration is shorter than classic external fixation in comparative literature, but pin sites overlap in time with an intramedullary implant and create a route for deep infection. ^[1][2]

Daily Experience

• PRECICE: controller positioning and prescribed sessions, load restriction, assistive devices, serial imaging, therapy, and incision monitoring.
• LON: frame adjustments, pin-site and frame care, clothing and sleep adaptations, prescribed loading, serial imaging, and therapy.

Operations and Removal

PRECICE does not require routine distal locking at the end of distraction because both ends are locked initially. LON generally includes a frame-removal and nail-locking transition. Both methods can require unplanned procedures, and internal nails later require device-specific removal planning. FDA instructions for titanium PRECICE IMLL state removal after one year. ^[3]

Loading Cannot Be Compared With One Number

Permitted load depends on the exact nail or frame, diameter, bone, number of operated limbs, phase, regenerate, alignment, and surgeon. LON may permit different loading because the frame and nail share stability, but earlier or fuller loading is not universal. Use the written plan for the exact construct.

Infection Trade-Off

A fully internal nail avoids pin-site infection but not all surgical or implant infection. LON adds pin sites near an intramedullary implant. A randomized 31-limb study reported shorter frame time and fewer overall events with LON than conventional Ilizarov treatment, while 3 of 15 LON limbs developed deep intramedullary infection. The benefit and harm must be presented together. ^[4]

Direct Comparison Evidence Is Limited

Comparative studies differ by indication, bone, era, device, surgeon, and outcome definitions. A femoral cohort favoring a magnetic nail over LON does not prove the same result for every tibial or cosmetic patient. Provider-specific current outcomes remain important. ^[5]

Current U.S. Device Status

The FDA states that stainless-steel Precice devices including STRYDE remain recalled and should not be implanted. A separate Class II recall covers specified PRECICE MAX catalog and lot combinations and remained open when the FDA record was updated on July 14, 2026. Do not treat STRYDE as available. For PRECICE MAX, verify the exact UDI or lot and current instructions rather than assuming that either every unit is recalled or every unit is available for high loading. ^[3][6]

Cost Depends on the Full Pathway

Implant price alone does not compare total cost. Include facility, frame, controller, operations, pin care, therapy, imaging, housing, lost work, removal, and complications. Published cost studies reflect one system and time and do not establish a current global price.

Ask the Same Questions for Both Methods

• Exact device or construct, fit, load restriction, current regulatory status, and planned operations.
• Provider outcomes for the same segment, indication, and method with clear denominators.
• Infection, joint, nerve, alignment, regenerate, implant, and revision protocols.
• Local stay, remote-care limits, therapy, caregiver, emergency, and total-cost plan.