1 Introduction

Short stature is defined as a height that is less than the 3rd percentile for the chronologic age of the patient.¹ Children with short stature have less normal psycho-social function and attention problems. Externalizing behavior problems and poor social skills are attributed to short stature.² Societal prejudices extend to short stature and may cause psychological disturbance, mostly in early adolescence but also in childhood as well.³

Over the past several decades; leg lengthening was applied to treat dwarfism and skeletal deformities caused by congenital abnormalities, trauma, tumor or infections.⁴ But lately, leg lengthening by the Ilizarov method (distraction osteogenesis) has been applied to patients with constitutional short stature who wish to be taller.⁵ This new technique is called cosmetic leg lengthening or symmetrical extended limb lengthening.⁶ Circular external fixators or monolateral fixators which have been widely used in surgeries are still being used for distraction osteogenesis. Lengthening with external fixators is related to pin-site infection, muscle contractures due to soft-tissue transfixation, joint stiffness and pain7. Prolonged use of an external fixator induce the duration of the patient's return to normal daily activities. Also refractures of regenerated bone can occur after fixator removal.⁸

Publications related to mechanical intramedular bone extensions are available in the literature. Cole et al. announced their first experience with their mechanically activated lengthening nail called the intramedullary skeletal kinetic distractor (ISKD) in 2001.⁹ Advantages of lengthening nails involve earlier rehabilitation, less pain, reduced risk of infection, malalignment and refracture.¹⁰ ISKD is a mechanical system and there are motorized systems called Fitbone®(Wittenstein, Iger-sheim, Germany) and Precice®(Ellipse Technologies, Irvine, CA,USA).

However, little is known about the use of lengthening nails to obtain height for cosmetic reasons. With this study, we wanted to share our experience at Dokuz Eylul University Hospital about the cosmetic bilateral limb lengthening by using different nail systems, and present the complications and limitations of this procedure.

2 Patients and methods

Between 2001 and 2018, a single-center, a single-operator (HH), the medical records of 9 patients with constitutional short stature (6 males, 3 females, 16 femurs, 2 tibias) who underwent cosmetic bilateral limb lengthening using three different nail systems, were reviewed retrospectively.

The mean age was 28.3; 29.3 in men and 26.3 in women. Mean height in men was 153 cm, in women 149 cm, both 151 cm. All patients practiced noncompetitive sports.

The authors evaluated clinical, psychological and radiological examinations of all patients. The patients who were able to understand the device, the magnet, the monitor, were emotionally stable, were able to cope with the difficulties of the treatment, and could adapt to the treatment program including rehabilitation. All of these selected patients had no illness or hormonal deficiency. When we asked the patients the reason why they accepted this procedure, two said that it was for professional purposes, and seven said that it was for social purposes.

Operative Technique, Post-operative Care and Follow-up. The surgery was organised in lateral decubitus position for the antegrade femur nail insertion and in supine for the tibia and retrograde femur. We first reamed intramedullary space 2 mm more then the nail diameter. With lateral approach about 5–7 cm down to the trochaner minor, two pins were inserted to control the rotation of the antegrade femur nail. For the retrograde femur, the osteotomy level was distal 2/3 of the femur and for tibia it was 5 cm below tuberositas. To facilitate axial alignment, a line was drawn between two pins. The next step was osteotomy using the multiple drill hole technique and the ossilating saw. The end step was nail insertion and locking the screws. Postoperatively, following one day of bed rest, mobilization with partial weight-bearing of 15 kg using underarm crutches was permitted. After the latent period that takes about 5–7 days, the lengthening phase started at a distraction rate or index of 1 mm per day for the femur and 0.5 mm for the tibia. Patients were informed cautiously about external remote controller (ERC) and were discharged to go home. During the lengthening phase, all patients except one, were followed up weekly and then every 6 weeks during the consolidation phase. Maximum lengthening possible with the current version of the PRECICE® nail was 65 mm.¹¹ One patient didn't fit the follow-up during lengthening period and came to our center about five months after the surgery (Fig. 1). The patient was walking without crutches. The lengthening was measured as 95 mm and sufficient bone regeneration was seen on X-rays (Fig. 2). Taking courage from this patient, the doctors thought that the other patients would have an extension of more than 65 mm and shared their thoughts with the other patients. The patients were briefed thoroughly about the complications and risks of lengthening more than 65 mm. All the patients wishing to undergo this surgery were invited to discuss the treatment with another patient. When the surgeon examined the internal structure of the extension nail on the x-ray, it was thought that the system allowed further extension but could cause mechanical failure. This thought was discussed with the patients. After informing and getting consent from patients, we continued to distraction until 100 mm. The radiological criteria for successful lengthening was complete bone bridging in at least two projections.³ The complication rate and the incidence of distraction problems were recorded and compared for femoral and tibial lengthenings.

Close

Fig. 1 41 years old patient initial X-ray and anterior-posterior radiograph of both limb 1 day after surgery.

Export to PPT

Close

Fig. 2 Anterior-posterior and lateral radiograph of both limb 5 months after surgery: good consolidation and proximal locking screw pull-out.

Export to PPT

3 Results

The mean lengthening achieved in all patients (9 patients, 16 femurs, 2 tibias) who underwent simultaneous leg lengthening surgery was 8.7 cm (Table 1). The mean follow-up period was 22 ± 11 months. Latent period was 5–7 days. After latent period distraction began after the surgery. The mean healing index (period between index operation and full weight-bearing without crutches) was 45 + 16 days/cm (Table 1).

In one patient (one limb) proximal locking screw of nail pulled out during distraction period (Fig. 2) and this nail was removed (Fig. 3). In two patients (two limbs) developed insufficient bone regeneration. One of this complication was due to inserting the nail more lateral from the appropriate starting point. After the distraction period, this nail was replaced by a non-distractor nail. One patient had a quadriceps-contracture (retrograde nail) in regard to the violation of the knee and the patient's other knee had no signs of contracture. No superficial or deep infection, fat embolism, deep vein thrombosis, or pulmonary embolism was observed during the entire follow-up period.

Close

Fig. 3 Anterior-posterior and lateral radiograph of both limbs 11 months after surgery: good consolidation, left side nail removed.

Export to PPT

At the latest follow-up, all the patients were satisfied with the improvement in self-esteem, distress or shyness and quality of life. When asked if they would have the procedure again, 8 said that they would and the remaining one would not.

4 Discussion

Limb lengthening surgeries have widely been used for the treatment of dwarfism and/or skeletal deformities caused by congenital abnormalities trauma, tumor or infections. Nowadays, limb lengthening has evolved from using external fixation to intramedullary devices. This study focuses on the good results of the limb lengthening with different nail systems for aesthetic reasons. In this study, we selected patients only who has short stature and wanted to be taller for cosmetic purposes.

One of the advantages of this study is being a single-center and single-surgeon series. This study had several limitations. First, the number of patients was relatively small. Second, we confirm that patients were not randomized and that only descriptive statistical analyses were performed. Except for one patient, patients were compatible with follow-up. And the patient, who did not show up for a regular follow up, helped us realise by chance that the nail could be longer than the manufacturer's guide without complication.

Bone lengthening surgeries are known as surgeries that have a high complication rate. In the literature from 24% to 117% for external fixation^12–14 and from 11% to 47% for intramedullary lengthening systems^15,16 have been reported. The overall complication rate in our study was %22. These different complication rates can be explained partially by lengthening over 6.5 cm and etiology. However, 2 of the 4 cases that we had complications were made with PRECICE® and the other two cases were made with a different system (Fitbone®, ISKD®). The case that we made with Fitbone® had a quadriceps contracture. This can be due to retrograde nail insertion regardless to distraction. One of the two cases where insufficient bone regeneration was developed was tibia, and in that case we had used PRECICE® and the other case was for femur lengthening and in that case ISKD was used. According to our observations, tibia lengthening could have more complications than femur regardless to the nail system.

5 Conclusion

In accordance with technological improvements, lengthening with intramedullary nail and especially cosmetic lengthening are gradually increasing. Moreover, complication rate is decreasing day by day as well.

Bone lengthening for aesthetic purposes with different nail systems can be very safe and beneficial for the patients, improving their social capabilities and self-confidence. Nevertheless, it may also cause many complications. Therefore, patients should be well informed about the complications and risks of the lengthening surgery.

Funding

There is no funding source.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent: Informed consent was obtained from all individual participants included in the study.