Risks and complications
Problems, obstacles and complications, with rates and what we do about each.
Methods compared
LON vs motorised nails vs Ilizarov: how limb lengthening methods compare
Three families of method are used to lengthen the tibia or femur in adults. This page sets out how each works, what the published studies report, and where the evidence is thin.
Reviewed by Dr. Aman Khanna, M.S. Orthopaedics, an orthopaedic surgeon. Limb lengthening is bone surgery, not physiotherapy.
For adults aged 18 and over whose growth plates have closed.
Short answer. Adults are lengthened by one of three methods. Lengthening over nail (LON) combines a standard intramedullary nail with a temporary external fixator. Motorised nails, Fitbone and PRECICE, lengthen from inside the bone with no frame. Ilizarov or LRS frames lengthen and hold the bone from outside throughout. All three carry real complication rates (PMID 32670567). Living Taller performs LON as its package method and offers the Fitbone nail at a surcharge.
Risks first. Every method starts with a cut through the bone and months of lengthening, so none avoids the main risks: infection, joint stiffness, nerve irritation, bone that heals too early or too late, and further surgery. In a systematic review of 795 cosmetic patients the mean was 0.78 problems, 0.94 obstacles and 0.15 complications per patient (PMID 32670567); those three grades are Paley’s, explained with rates on the risks and complications page. All figures below are literature figures from other centres, with different patients and definitions. They are not our results.
How each method works
Lengthening over nail (LON)
A standard intramedullary nail, one that does not lengthen itself, is placed in the bone canal. An external fixator (an LRS monolateral frame, as decided at consultation) is fixed to the bone with pins and adjusted by a small amount each day. When the target length is reached the nail is locked at its other end and the frame is removed in a second, smaller operation, so the nail carries the bone while the new bone hardens (PMID 15523010, PMID 31506759). The aim is a shorter time in the frame than with a frame alone (PMID 15523010). The costs are a visible frame, daily pin-site care and a second operation.
Motorised nails: Fitbone and PRECICE
A telescoping nail with a motor sits entirely inside the bone, so there is no frame and no pin site. The Fitbone is stainless steel and is driven by an electrical current passed through a subcutaneous antenna; the PRECICE is titanium and is driven by a rotating magnet moved with an external remote controller (PMID 40224160). The surgeon sets the daily lengthening. Living Taller offers the Fitbone at a surcharge quoted at consultation. PRECICE is described because patients ask about it and because it is the other motorised family on the market; it is not part of our offer. Nail removal is not part of the package price.
Frame only: Ilizarov and LRS
The bone is cut and held entirely by an external frame: a circular Ilizarov ring fixator with wires and pins, or a one-sided frame such as the LRS. The same frame lengthens the bone and holds it until the new bone has hardened, so it stays on for the whole treatment. This is the oldest method (PMID 2403498) and it still appears in cosmetic series (PMID 25183215, PMID 27837313). It is described here so that you can compare quotes. It is not our package method.
Side by side
Figures come from different series, populations and definitions, and cannot be compared line by line.
| LON | Motorised nail (Fitbone, PRECICE) | Frame only (Ilizarov, LRS) | |
|---|---|---|---|
| What lengthens the bone | A small daily adjustment of the external fixator | The motor in the nail, set by the surgeon | A small daily adjustment of the frame |
| What holds the bone | The nail, plus the frame until the target length is reached | The nail | The frame, throughout |
| Hardware outside the body | Frame during lengthening, then removed | None | Frame during lengthening and consolidation |
| Gain per segment | Our planning rule is the same for all three: up to about 6 cm per segment, decided from X-rays. Published mean gains in cosmetic series: 6.3 cm in a LON series (PMID 15523010), 6.65 cm in 143 bilateral tibial LON cases (PMID 25081825), 6.9 cm with Ilizarov frames (PMID 25183215). Motorised-nail series are mostly not cosmetic and report means of about 4 to 5 cm (PMID 40224160, PMID 26874445). | ||
| Distraction rate | About 0.8 to 1 mm a day for all three, set by the surgeon and adjusted from X-rays and symptoms (PMID 29983659). A rate above 1.5 mm a day went with poor new bone in a mechanical-nail series (PMID 20638660). | ||
| Time with the frame on | External fixation index 18.7 days per cm (PMID 15523010); mean 93.7 days in 143 bilateral tibial cases (PMID 25081825) | Not applicable | External fixator index 31 days per cm, range 12 to 78 (PMID 25183215); about one month per cm in an early series (PMID 2403498) |
| Bone healing (indices are defined differently) | Femoral union at 4.5 months (PMID 29983659) | Femoral union at 3.3 months (PMID 29983659); healing index 31.3 days per cm for PRECICE against 47.1 for an LRS frame (PMID 27694593); Fitbone 35 days per cm in femurs and 48 in tibiae (PMID 21561309), 73 and 83.5 in another series (PMID 26874445) | Healing index 47.1 days per cm with the LRS frame (PMID 27694593) |
| Complications reported | 0.43 per segment, 38 percent of segments (PMID 15523010); 0.74 per segment, 0.45 without pin-tract infection (PMID 25081825) | 34 percent of 983 segments, mostly non-cosmetic patients; device and bone complications most frequent (PMID 33106069); mechanism failure in 4.3 percent of 2,495 nails (PMID 41869489) | 37 percent of 131 patients, 59 complications (PMID 25183215) |
| Method-specific issues | Pin-site infection; joint stiffness while the frame is on; a second operation to remove it | Jamming or failure of the mechanism, needing nail exchange (PMID 41869489); antenna irritation and bolt migration in one Fitbone group (PMID 40224160) | Pin-site infection; axial deformity and fracture of the new bone (PMID 31506759); the longest frame time |
| Operations (US femoral series) | 3.1 on average (PMID 30278015) | 2.1 on average (PMID 30278015) | Not reported there |
| Main cost drivers | Nail and frame, two operations, hospital days | Higher implant cost, fewer operations | Frame, the longest frame time and follow-up |
| At Living Taller | Package method | Fitbone at a surcharge quoted at consultation; PRECICE not offered | Not part of the package |
What head-to-head studies show
Direct comparisons exist but are small, retrospective and mostly not cosmetic.
- In a femoral series of 22 LON and 40 motorised-nail lengthenings, 18 percent of the nail group and 45 percent of the LON group had a complication, and union took 3.3 against 4.5 months. Knee flexion at the end of lengthening was 105 against 88.8 degrees, but the difference was gone after a year (PMID 29983659).
- In 33 femoral cases, PRECICE had a healing index of 31.3 days per cm against 47.1 for the LRS frame, and the frame group had more pin-site infections and new-bone deformity (PMID 27694593).
- In a meta-analysis of 489 cosmetic patients, external fixation had problems in 56 percent, obstacles in 48 percent and complications in 10 percent, against 37 percent, 42 percent and no significant complications for intramedullary nailing. The authors called both viable (PMID 39801900).
- A matched comparison of 27 patients found no difference in new-bone formation between Fitbone and PRECICE. Bolt migration, premature consolidation and antenna irritation occurred in the Fitbone group and none was recorded in the PRECICE group; the authors put this down to the learning curve of a new implant (PMID 40224160).
Where the studies favour the motorised nail on frame-related problems, we say so. The nail also costs more and brings device-specific risks: mechanism failure, nail exchange and a reported complication rate of 34 percent of segments (PMID 33106069, PMID 41869489). We found no randomised trial comparing lengthening methods in cosmetic patients (PubMed, 9 October 2026; search string in the references note). The randomised evidence we found concerns pin coating in short-stature lengthening (PMID 15330032, PMID 12925633), not the choice of method. We make no claim that one method is better for you.
Gain, time and cost
Gain per segment
Up to about 6 cm per segment, decided from X-rays, whichever method is used. That is our planning rule, not a published limit. In LON, lengthening of more than 6 cm, or more than 21.5 percent of the original bone length, went with a higher chance of complications (PMID 15523010). The tibia and femur are separate segments, each lengthened in its own stage. The height-after-LON tool shows how segments add up.
Time
You stay in Surat for the whole lengthening phase, usually six to ten weeks per stage, with supervised physiotherapy; you fly home once lengthening is complete and the frame is off, and the bone consolidates at home with remote review. Recovery from surgery to full activity is 12 to 18 months for cosmetic cases with any method; one Ilizarov series reported 7 to 18 months of treatment (PMID 27837313). Frame time differs. Using the LON index of 18.7 days per cm (PMID 15523010), a 6 cm segment is about 4 months in the frame by our arithmetic; the Ilizarov index of 31 days per cm (PMID 25183215) gives about 6 months. Your own time is decided from X-rays.
Cost
Cost follows the implant, the number of operations, the hospital and rehabilitation days, and the number of segments. A motorised nail costs more as an implant; in one US series that was offset by fewer operations, and total costs were similar (PMID 30278015). Consultation fee INR 10,000. Surgery fees are quoted after assessment. The international package for bilateral tibial or bilateral femoral lengthening with LON is listed from USD 15,000 to 16,000; the what is included page itemises it. The Fitbone surcharge is quoted at consultation, and a tibia-then-femur plan is two packages with a combined price quoted at consultation. See also the cost calculator.
Who suits which
Every method needs an adult with closed growth plates, standing long-leg X-rays, an examination and a psychological assessment first (PMID 30399986, PMID 39801900).
- LON suits a person who accepts a visible frame for a few months, will do daily pin-site care and physiotherapy, and wants the lower implant cost.
- A motorised nail suits a person for whom having no frame matters most and who accepts a higher implant cost and a device that can fail mechanically. Each implant has manufacturer limits on canal size and body weight, checked from your X-rays.
- Frame only is the older approach (PMID 2403498). Ask what any such quote includes, how long the frame stays on, and what happens if a complication needs another operation.
References
- Pizà G, et al. Hydroxyapatite-coated external-fixation pins. The effect on pin loosening and pin-track infection in leg lengthening for short stature. J Bone Joint Surg Br. 2004;86:892-7. PMID 15330032
- Caja VL, et al. Hydroxyapatite coating of external fixation pins to decrease axial deformity during tibial lengthening for short stature. J Bone Joint Surg Am. 2003;85:1527-31. PMID 12925633
- Marwan Y, et al. Cosmetic stature lengthening: systematic review of outcomes and complications. Bone Joint Res. 2020;9:341-350. PMID 32670567
- Bulut H, et al. Meta-analysis of complications and functional outcomes in cosmetic limb lengthening. J Orthop. 2025;65:41-45. PMID 39801900
- Paley D, et al. Problems, obstacles, and complications of limb lengthening by the Ilizarov technique. Clin Orthop Relat Res. 1990:81-104. PMID 2403498
- Kocaoglu M, et al. Complications encountered during lengthening over an intramedullary nail. J Bone Joint Surg Am 2004 86. 2406;-11. PMID 15523010
- Motallebi Zadeh N, et al. Bilateral tibial lengthening over the nail: our experience of 143 cases. Arch Orthop Trauma Surg 2014 134. 1219;-25. PMID 25081825
- Farsetti P, et al. Lower limb lengthening over an intramedullary nail: a long-term follow-up study of 28 cases. J Orthop Traumatol. 2019;20:30. PMID 31506759
- Kocaoglu M, et al. Results of cosmetic lower limb lengthening by the lengthening over nail technique. Acta Orthop Belg. 2017;83:231-244. PMID 30399986
- Novikov KI, et al. Cosmetic lower limb lengthening by Ilizarov apparatus: what are the risks? Clin Orthop Relat Res 2014 472. 3549;-56. PMID 25183215
- Guerreschi F, et al. Cosmetic lengthening: what are the limits? J Child Orthop. 2016;10:597-604. PMID 27837313
- Frost MW, et al. Systematic review of complications with externally controlled motorized intramedullary bone lengthening nails (FITBONE and PRECICE) in 983 segments. Acta Orthop. 2021;92:120-127. PMID 33106069
- Kostin E, et al. Mechanism Failures in Externally Controlled Motorized Intramedullary Lengthening Nails: A Systematic Review. JB JS Open Access. 2026;11. PMID 41869489
- Calder P, et al. Fitbone vs Precice: Is There a Difference in Regenerate Healing? Strategies Trauma Limb Reconstr. 2024;19:156-160. PMID 40224160
- Krieg AH, et al. Intramedullary leg lengthening with a motorized nail. Acta Orthop. 2011;82:344-50. PMID 21561309
- Accadbled F, et al. Bone lengthening using the Fitbone(®) motorized intramedullary nail: The first experience in France. Orthop Traumatol Surg Res. 2016;102:217-22. PMID 26874445
- Laubscher M, et al. Outcomes following femoral lengthening: An initial comparison of the Precice intramedullary lengthening nail and the LRS external fixator monorail system. Bone Joint J 2016 98-B. 1382;-1388. PMID 27694593
- Fragomen AT, et al. A Comparison of Femoral Lengthening Methods Favors the Magnetic Internal Lengthening Nail When Compared with Lengthening Over a Nail. HSS J. 2018;14:166-176. PMID 29983659
- Richardson SS, et al. Cost Comparison of Femoral Distraction Osteogenesis With External Lengthening Over a Nail Versus Internal Magnetic Lengthening Nail. J Am Acad Orthop Surg. 2019;27:e430-e436. PMID 30278015
- Kenawey M, et al. Leg lengthening using intramedullay skeletal kinetic distractor: results of 57 consecutive applications. Injury. 2011;42:150-5. PMID 20638660
Search note: PubMed, 9 October 2026, ("limb lengthening"[tiab] OR "leg lengthening"[tiab] OR "distraction osteogenesis"[tiab] OR "lengthening over nail"[tiab] OR "intramedullary lengthening"[tiab]) AND randomized controlled trial[pt] returned 68 records. We screened the titles: none compared LON, motorised nails and external frames for cosmetic lengthening. Randomised comparisons of frames exist in infected tibial nonunion, not in cosmetic patients.
Questions people ask
What is the difference between LON and PRECICE?
LON uses a standard nail plus an external frame that is worn while the bone lengthens and then removed. PRECICE is a nail that lengthens from inside the bone, driven by an external magnetic controller, so there is no frame (PMID 40224160). The trade is a frame and pin care against a more costly implant whose mechanism can fail (PMID 41869489). Living Taller performs LON and offers the Fitbone motorised nail at a surcharge. PRECICE is not part of our offer.
Is a motorised nail safer than lengthening over nail?
Some retrospective comparisons report fewer complications and a shorter time to union with a motorised nail (PMID 29983659, PMID 27694593), and a cosmetic meta-analysis found fewer problems and obstacles with intramedullary nailing than with external fixation (PMID 39801900). Motorised nails also have complications of their own: 34 percent of 983 segments in one review (PMID 33106069). The studies are small and retrospective, and we found no randomised trial comparing LON, motorised nails and frames in cosmetic patients (PubMed, 9 October 2026; search string in the references note). The randomised trials that exist concern pin coating in short-stature lengthening (PMID 15330032, PMID 12925633), not the choice of method. We do not claim that one method is safer for you; that is decided from your X-rays.
Is the Ilizarov method still used for limb lengthening?
Yes. Frame-only lengthening is the oldest method and is still reported in cosmetic series (PMID 25183215, PMID 27837313). In one series of 131 patients, 37 percent had at least one treatment-related complication and the mean external fixator index was 31 days per cm (PMID 25183215). In the LON series we cite the external fixation index was 18.7 days per cm (PMID 15523010). These are different centres and patients, so the figures are context, not a head-to-head result.
How much height can each method add?
Our planning rule is the same whichever method is used: up to about 6 cm per segment, decided from X-rays. A systematic review of 795 cosmetic patients reported a mean gain of 6.7 cm, with a range of 1.5 to 13.0 cm (PMID 32670567). The tibia and femur are separate segments, lengthened in separate stages. The height-after-LON tool shows how segments add up.
How long will I be in a frame with LON?
Published LON series report an external fixation index of 18.7 days per cm (PMID 15523010) and a mean fixator period of 93.7 days in 143 bilateral tibial cases (PMID 25081825). By our arithmetic from the first figure, a 6 cm segment is about 4 months. Your own time is decided from X-rays. Total recovery from surgery to full activity is 12 to 18 months for cosmetic cases.
What does the Fitbone surcharge cost?
It is quoted at consultation, because it depends on the segments and the plan. Consultation fee INR 10,000. Surgery fees are quoted after assessment. The international package for bilateral tibial or bilateral femoral lengthening with LON is listed from USD 15,000 to 16,000, and the what is included page itemises it. A US hospital series found similar total costs for LON and a magnetic nail because the nail needed fewer operations (PMID 30278015). That is not a prediction of our prices.
Related pages
What is included
The itemised package: included, not included, quoted separately.
Aftercare when you fly home
Tele-follow-up, X-ray review and the written complication pathway.
Height after LON
An educational estimate, one segment at a time.
Cost calculator
Work out the cost for the segments you are considering.
The limb lengthening process
Stage by stage, from surgery to full activity.
Contact the surgeon
Send your height, age and any X-rays you have. The method, the segments and the target for each are decided at consultation, after a psychological assessment. This page is information, not a plan.