Femoral lengthening with a motorized intramedullary nail

Purpose — We assessed whether an intramedullary lengthening device would reduce the problems normally associated with the external fixation technique. We also wanted to determine whether it is a reliable construct for limb lengthening and deformity correction in the femur.

Patients and methods — We conducted a matched-pair comparison of 30 femoral lengthenings, 15 with a motorized intramedullary nail (the nail group) and 15 lengthenings with an external ring fixator (the fixator group). The patients were matched based on age, sex, amount of lengthening, and the etiology of leg length discrepancy. Mean lengthening was 35 (25–55) mm in the nail group and 38 (15–75) mm in the fixator group. Outcome measures were: lengthening and alignment achieved, consolidation index, knee range of motion (ROM), and complications.

Results — The pairs in this matched-pair study were similar in terms of age, sex, diagnosis, and amount of lengthening. The planned amount of lengthening was achieved in all patients in both groups and axis correction was considered sufficient. The mean radiographic consolidation index in the nail group, at 1.5 (0.9–3.0) months/cm, was better than the mean value for the fixator group (1.9 (0.9–3.4) months/cm) (p = 0.01). Knee ROM was better in the nail group during the lengthening, 6 weeks after lengthening was completed, and 6 months after lengthening was completed (p < 0.001). A larger number of complications were observed in the fixator group than in the nail group.

Interpretation — A lengthening nail may be superior to external fixation in femoral lengthening, when the anatomical conditions and the complexity of the deformity allow the use of an intramedullary nail.     

Lengthening of the femur over an existing intramedullary nail

Leg length discrepancies can occur despite successful union of femur fractures after intramedullary nailing (IMN). Often, the leg length discrepancy can result in significant disability to the patient, altered gait biomechanics, pelvic obliquity, and pain. Therefore, a successful clinical result for such deformities after IMN involves addressing the leg length inequality. Femoral reconstruction with an osteotomy around an existing intramedullary nail was introduced to address axial deformity correction and limb lengthening without changing or removing a previously inserted IMN. This technique uses the principles of lengthening over an IMN. The presence of the nail has minimized the time needed for the external fixator because the nail supports the regenerate bone or osteotomy during the consolidation phase. With this technique, surgery is minimized by avoiding the need for exchange nailing.     

Distraction osteogenesis of the femur using conventional monolateral external fixator

INTRODUCTION: The author has developed a new simple technique of distraction osteogenesis using conventional monolateral external fixator for femoral lengthening. The primary purpose of the present study was to evaluate the results of treatment with this new technique of femoral lengthening and also to evaluate the effect of preoperative and intraoperative variables on the outcome of distraction osteogenesis in general. MATERIALS AND METHODS: Fifty-one femora in 50 patients were lengthened. Limb-length discrepancy was the primary indication in all patients. The mean age of the patients at the time of the surgery was 21.9 years (range 5-48 years). The average follow-up period was 24.6 months after removal of the fixator (range 6-120 months). All lengthenings were performed using conventional AO/ASIF external fixator. Twenty-two femora had associated axial or rotational deformities. Gradual distraction was performed to increase length and to correct angular deformity in coronal plane. Acute closed wedge angular correction in sagittal plane or derotation was performed in 12 femora in this study. RESULTS: The length of the 51 femora was increased by an average 4.4 cm (range 1-13 cm), or 12% (range 2.5-40.9%). The average healing index was 50.5 days/cm (range 22.5-110.6 days/cm). Average gradual angular correction in coronal plane in 14 femora was 20.4 degrees (range 10-45 degrees ). Average acute correction in sagittal plane in five femora was 17 degrees (range 10-20 degrees ). Average acute derotation in six femora was 24.2 degrees (range 10-60 degrees ). There were a total of 61 complications, including 26 problems, 18 obstacles, and 17 sequelae. The overall rate of complications was 1.2 per femur. Fifteen femora had delayed consolidation (healing index >54 days/cm). Three of 51 lengthening procedures did not lead to consolidation (nonunion). A significant negative parabolic relationship was noted between the healing index and the amount of length gained (R = -0.47 and P = 0.004). There was a significantly positive exponential relationship between age and healing index (R = 0.51 and P < 0.001). Acute deformity correction, level of osteotomy (submetaphysis versus diaphysis) had no significant effect on healing index. The greater amount of length gained was associated with complications. CONCLUSIONS: The newly presented technique of distraction osteogenesis is a useful and cost-effective method for femoral lengthening. Increased lengthenings produced a better healing index but might associate with complications. Younger age was associated with better bone healing but age had no effect on complication rate. Level of osteotomy, acute deformity correction had no effect on healing index and rate of complications.     

Tibial lengthening and concomitant foot deformity correction in 14 patients with permanent deformity after poliomyelitis

Background In neuromuscular diseases, limb lengthening and foot deformity correction are associated with a high risk of complications associated with distraction callus and joint contracture. We have found no published articles of tibial lengthening and concomitant foot deformity correction using the Ilizarov method or traditional methods. To compare result of gradual distraction with triple arthrodesis for foot deformity combined with tibial lengthening, we investigated healing index and complications of two methods.

Patients and methods We reviewed 14 patients with permanent deformity after poliomyelitis who underwent tibial lengthening and concomitant foot deformity correction using the Ilizarov external fixator. Tibial lengthening over an intramedullary nail was performed in 3 patients and lengthening without a nail was performed in 11 patients.

Results The mean external fixation time was 6 (3.6- 10) months without nail and 1.6 (1.5-1.7) months with nail, whereas the mean healing index was 1.8 (0.8-3.1) months/cm without nail and 2 (1.8-2.3) months/cm with nail. Concomitant foot treatments included triple arthrodesis in 7 patients, pantalar arthrodesis in 2 patients with fiail ankle, and gradual foot frame distraction without bony foot procedures in 5 patients. Delayed consolidation and recurrent equinus contracture of the ankle requiring additional lengthening of the Achilles tendon were the most common bone and joint complications during tibial lengthening.

Interpretation The gradual foot frame distraction method was associated with major complications, such as recurrent foot deformity, joint luxation, and arthritis. We therefore recommend triple arthrodesis as a concomitant procedure during tibial lengthening     

Bone realignment with use of temporary external fixation for distal femoral valgus and varus deformities

BACKGROUND: Correction of a distal femoral deformity may prevent or delay the onset of osteoarthritis or mitigate its effects. Accurate correction of deformity without production of a secondary deformity depends on precise localization and quantification of the deformity. We report a technique to correct distal femoral deformities in the coronal plane. METHODS: Fourteen femora in thirteen skeletally mature patients with a distal femoral deformity underwent operative reconstruction. The preoperative deviation of the mechanical axis ranged from 90 mm laterally (genu valgus) to 120 mm medially (genu varus). The mechanical lateral distal femoral angle was abnormal in all fourteen knees. The technique consisted of application of an external fixator, performance of a percutaneous distal femoral dome osteotomy, correction of the deformity, and locking of the external fixator. A statically locked retrograde intramedullary nail was inserted following reaming, and the external fixator was removed. The mean duration of follow-up was thirty-three months (range, six to forty-seven months). RESULTS: The mean time until healing was thirteen weeks (range, six to thirty-nine weeks). Nine of the thirteen patients reported an improvement in walking, and none needed an assistive device. All nine patients with preoperative knee pain were free of tibiofemoral pain at the most recent follow-up evaluation. The mechanical lateral distal femoral angle was within the normal range in twelve of the fourteen knees. The mechanical axis was within the normal range in ten lower extremities. In three of the four remaining limbs, the residual abnormal deviation of the mechanical axis was due to a residual tibial deformity. CONCLUSIONS: Percutaneous dome osteotomy combined with temporary external fixation and insertion of an intramedullary nail can correct distal valgus and varus femoral deformities. We attributed the early mobilization of patients and the rapid bone-healing to the limited soft-tissue dissection, the low-energy corticotomy, and the use of intramedullary fixation in our surgical technique.     

Limb lengthening and deformity correction of congenital and acquired deformities in children using the Taylor Spatial Frame

Background and purpose — Hexapod ring fixators such as the Taylor Spatial Frame (TSF) have shown good outcomes. However, there have only been a few studies comparing the use of TSF with various etiologies of the deformity. We compared the use of TSF in congenital and acquired deformities in children.

Patients and methods — We reviewed 213 lower extremity reconstructive procedures with the TSF in 192 patients who were operated between October 2000 and October 2015. 128 procedures (67 proximal tibiae, 51 distal femora, and 10 distal tibiae) in 117 children (median age 14 (4–18) years; 59 girls) fulfilled the inclusion criteria. 89 procedures were done in children with congenital deformities (group C) and 39 were done in children with acquired deformities (group A). Outcome parameters were lengthening and alignment achieved, lengthening index, complications, and analysis of residual deformity in a subgroup of patients.

Results — Mean lengthening achieved was 3.9 (1.0–7.0) cm in group C and 3.7 (1.0–8.0) cm in group A (p = 0.5). Deformity parameters were corrected to satisfaction in all but 3 patients, who needed further surgery for complete deformity correction. However, minor residual deformity was common in one-third of the patients. The mean lengthening index was 2.2 (0.8–10) months/cm in group C and 2.0 (0.8–6) months/cm in group A (p = 0.7). Isolated analysis of all tibial and femoral lengthenings showed similar lengthening indices between groups. Complication rates and the need for secondary surgery were much greater in the group with congenital deformities.

Interpretation — The TSF is an excellent tool for the correction of complex deformities in children. There were similar lengthening indices in the 2 groups. However, congenital deformities showed a high rate of complications, and should therefore be addressed with care.     

The management of leg-length discrepancy in Ollier's disease with a fully implantable lengthening nail

Ollier's disease is characterised by severe deformity of the extremities and retarded growth because of multiple enchondromas. For correction of deformity, the Ilizarov method has been used although it has many complications. A 17-year-old boy with Ollier's disease had a limb-length discrepancy of 17.4 cm, with a valgus deformity of the right knee and recurvatum of the femur of 23 degrees . He had undergone three unsuccessful attempts to correct the deformities by using external fixators. We used a fully implantable, motorised, lengthening and correction nail (Fitbone) to achieve full correction of all the deformities without complications. We decided to carry out the procedure in three stages. First, we lengthened the femur by 3.6 cm and the tibia by 4 cm. We then exchanged the femoral nail for a longer implant and achieved a further 6 cm of length. This reduced the shortening to 3.8 cm. When the boy has finished secondary school we will adjust the remaining discrepancy.     

Limb lengthening with a fully implantable mechanical distraction intramedullary nail

AIM: The morbidity of fixator-assisted distraction osteogenesis should be reduced by intramedullary lengthening devices. The ISKD (intramedullary skeletal kinetic distractor) is a new, fully implantable mechanical lengthening nail. In a prospective cohort trial the possibilities and limitations of the device used on femur and tibia are examined. METHODS: 22 patients with a mean age of 25 (range: 16-46) years were treated with an ISKD for femoral (n = 16) and tibial (n = 6) lengthening. The average leg length discrepancy was 48 (range: 25-80) mm. The follow-up was 21 (range: 7-37) months. Clinical and radiological results and complications were evaluated. RESULTS: The results of femoral and tibial applications of the ISKD are different. At the tibia, in three patients a pseudarthrosis occurred and slow callus formation was observed twice. An equinus contracture became evident in 2 patients. At the femur, in one case the lengthening was not accomplished with the device. Five patients were manipulated under anaesthesia at least once to achieve the aim of distraction. Three of these patients received retrograde implantation of the ISKD. An infection or interlocking screw failure was not observed either at the femur or the tibia. CONCLUSION: The ISKD reduces fixator-associated problems but incorporates its own difficulties which are mainly based on the guidance of the device. Careful patient advice in monitoring the lengthening process is mandatory. At the femur 8 cm of lengthening can be achieved but the nail tends to "block". Proper reaming and osteotomy techniques are important. A lengthening of more than 1 mm/day is recommended to prevent early consolidation. At the tibia weak callus formation and soft tissue contractures occur, therefore not more than 4 cm lengthening should be planned, the distraction speed has to be reduced noticeable below 1 mm/day and the initial immobilisation should be for more than a week.     

Korrekturosteotomien des distalen Femur mit retrogradem Marknagel

Deformities of the distal femur are usually corrected by supracondylar osteotomy. In the "classical" procedure the bone cut is performed with an oscillating saw, and internally fixed using a plate. This technique is hampered first by an invasive approach and second by limited corrective options in case of complex deformities. A supracondylar bone cut by focal dome osteotomy or drill osteoclasis in combination with internal fixation by retrograde intramedullary nailing (RN) might be a promising alternative procedure. 12 patients with multidimensional post-traumatic deformities of the distal femur were prospectively enrolled in a study to investigate this new minimal-invasive technique. In all patients a meticulous analysis of leg geometry was done pre- and postoperatively. Details of operative planning, osteotomy and fixation procedure are given as well as the postoperative treatment. 7 corrective osteotomies were one-step procedures, in 5 patients additional lengthening over the RN was performed using unilateral external fixation. The mean follow-up was 15 (range 7-27) months. All of the osteotomies healed in a normal expected time frame. All patients had important functional benefits. In 11 patients the goal of deformity correction was achieved. In one patient the correction in the frontal plane remained insufficient. 6 months after the completion of femoral lengthening osteomyelitis developed in one patient, probably due to a pin-track infection. The infection subsided after early removal of the RN. No further complications were observed. The presented technique is demanding concerning pre-operative planning and surgical realization but it offers a minimal-invasive and promising approach for the correction of multidimensional femoral deformities.     

Correction of angular deformities by physeal distraction.

Physeal distraction is an alternative to more conventional treatments for the correction of angular deformities of the long bones. Twenty deformities of the femur and tibia, nine of which also involved associated shortening, were partially or completely corrected. In eight cases, there was physeal bony bridge. Complete correction of the angular deformity was achieved in 17 patients, and in seven patients, more than 80% correction was achieved. There were complications in four patients that hindered complete correction of the deformity, or shortening, or both. The external control of the correction until consolidation occurs is progressive and fairly noninvasive. The method allows external control of the correction until consolidation; it acts at the site of the deformity itself and permits lengthening and angular correction during therapy. In deformities with a physeal bony bridge, correction can be achieved with physeal distraction alone, prior resection of the bridge is not unnecessary. The technique is indicated in cases of angular deformities in patients nearing skeletal maturity and particularly in subjects in whom there is associated shortening.     

Corrective Osteotomy of the Distal Femur by Retrograde Nailing

Abstract Objective: Correction of deformities of distal femur by a supracondylar dome or drill hole osteotomy in combination with a retrograde intramedullary nailing as an alternative to the classic technique of osteotomizing with an oscillating saw and internally fixating with a blade plate. In addition, leg length discrepancies can be corrected by the use of a unilateral distraction fixator after correction of axial and torsional deformities. Indications: Multidimensional deformities of the distal femur. Deformities of the distal femur with shortening > 1.5 cm. Deformities of the distal femur in the presence of length discrepancy and torsional deformity of the lower leg. Distal femoral deformities that may later need to be treated with a total knee replacement. Contraindications: State after local bone or soft tissue infections. A condylar bone stock insufficient for purchase of screws for intramedullary locking. Surgical Technique: Knee arthroscopy. Determination of the entry point and direction of insertion of the intramedullary nail in the frontal and sagittal plane. Insertion of the nail up to the level of osteotomy, placement of Schanz screws proximal and distal to the planned osteotomy for later assessment of the degree of correction. Either dome os teotomy or drill hole osteotomy. Correction of axial and torsional malalignments. Advancing of nail and static locking. Optional: for intended callus distraction, mounting of a unilateral distraction fixator. Results: Follow-up after 29 (4–45) months of 18 patients, seven with callus distraction. The goal of correction was reached in 17 patients. Three nonunions and one osteomyelitis healed after surgical revision. The following is a reprint from Operat Orthop Traumatol 2003;15:363–86 and continues the new series of articles at providing continuing education on operative techniques to the European trauma community. Reprint from: Operat Orthop Traumatol 2003;15:363–86 DOI 10.1007/s00064-003-1084-5     

Tibial lengthening over an intramedullary nail

Background Long-term application of an external fixator to treat leg-length discrepancy and short stature often causes complications, such as pin-tract infection or loss of range of motion at the knee or ankle (or both). Prolonged fixator use also interferes with the activities of daily living. To minimize such problems, we have combined intramedullary nailing with external fixation. Using this technique, the external fixator can be removed more quickly after completing the lengthening. Methods We combined intramedullary nailing with lengthening in 13 tibias (8 patients) and then compared these cases with 17 standard tibial lengthenings (16 patients) using an external fixator alone. In both groups we excluded patients who had a history of previous bone infection, open fracture, immature bone, soft tissue compromise, antineoplastic chemotherapy, or bone deformity of a severity that required gradual deformity correction. We also excluded cases with lengthening of less than 3 cm. Results The mean external fixation index differed significantly between the two groups, but the consolidation index did not. Mean operating time for lengthening combined with intramedullary nail placement was approximately 60 min longer than for standard lengthening without nail placement; intraoperative blood loss was not greater in the nailing group. Complications related to the external fixator were far fewer in the combined intramedullary nailing and lengthening group compared with the control group, and callus formation was satisfactory for both groups. Conclusions A combination of intramedullary nailing and external fixation produces callus formation as good as that obtained by the standard Ilizarov method of lengthening. Furthermore, this combined procedure decreases the external fixation time and is associated with fewer complications.     

The intramedullary elongation nail for femoral lengthening

We have analysed the results of 24 femoral lengthenings in 23 patients operated on between 1993 and 2000, using a gradual elongation intramedullary nail (Albizzia). Of the 23 patients, 22 had femoral deficiency and one was of short stature. Their mean age was 16.9 years. Technical difficulties encountered during the procedure were mild or moderate in 18 femora and severe in six femora. Distraction was obtained by 15 ratchetings per day (1 mm/day). There were 18 excellent results although in two patients this was achieved after the development of a pseudarthrosis which required further surgery. There were four good and two fair results in which the lengthening obtained was at least 3 cm less than had been projected. The consolidation index was 35.2 days/cm. No patient had associated long-term stiffness of the knee. Femoral lengthening using an elongation nail gives good results and is a comfortable procedure.     

Limb lengthening and correction of deformity in the lower limbs of children with osteogenesis imperfecta

We performed limb lengthening and correction of deformity of nine long bones of the lower limb in six children (mean age, 14.7 years) with osteogenesis imperfecta (OI). All had femoral lengthening and three also had ipsilateral tibial lengthening. Angular deformities were corrected simultaneously. Five limb segments were treated using a monolateral external fixator and four with the Ilizarov frame. In three children, lengthening was done over previously inserted femoral intramedullary rods. The mean lengthening achieved was 6.26 cm (mean healing index, 33.25 days/cm). Significant complications included one deep infection, one fracture of the femur and one anterior angulation deformity of the tibia. The abnormal bone of OI tolerated the external fixators throughout the period of lengthening without any episodes of migration of wires or pins through the soft bone. The regenerate bone formed within the time which is normally expected in limb-lengthening procedures performed for other conditions. We conclude that despite the abnormal bone characteristics, distraction osteogenesis to correct limb-length discrepancy and angular deformity can be performed safely in children with OI.     

Tibial lengthening and concomitant foot deformity correction in 14 patients with permanent deformity after poliomyelitis

BACKGROUND: In neuromuscular diseases, limb lengthening and foot deformity correction are associated with a high risk of complications associated with distraction callus and joint contracture. We have found no published articles of tibial lengthening and concomitant foot deformity correction using the Ilizarov method or traditional methods. To compare result of gradual distraction with triple arthrodesis for foot deformity combined with tibial lengthening, we investigated healing index and complications of two methods. PATIENTS AND METHODS: We reviewed 14 patients with permanent deformity after poliomyelitis who underwent tibial lengthening and concomitant foot deformity correction using the Ilizarov external fixator. Tibial lengthening over an intramedullary nail was performed in 3 patients and lengthening without a nail was performed in 11 patients. RESULTS: The mean external fixation time was 6 (3.6-10) months without nail and 1.6 (1.5-1.7) months with nail, whereas the mean healing index was 1.8 (0.8-3.1) months/cm without nail and 2 (1.8-2.3) months/cm with nail. Concomitant foot treatments included triple arthrodesis in 7 patients, pantalar arthrodesis in 2 patients with flail ankle, and gradual foot frame distraction without bony foot procedures in 5 patients. Delayed consolidation and recurrent equinus contracture of the ankle requiring additional lengthening of the Achilles tendon were the most common bone and joint complications during tibial lengthening. INTERPRETATION: The gradual foot frame distraction method was associated with major complications, such as recurrent foot deformity, joint luxation, and arthritis. We therefore recommend triple arthrodesis as a concomitant procedure during tibial lengthening     

Anwendung motorisierter Verlängerungsmarknägel am wachsenden Skelett

Background

Limb lengthening and deformity correction with motorized intramedullary lengthening nails is a more comfortable and equally safe procedure than the use of external fixators. While this treatment is a well-established method in adults, intramedullary nailing for skeletally immature patients remains a challenge and is the focus of current clinical investigations.

Objective

Elucidation of the indications for the application of femoral and tibial lengthening nails in skeletally immature patients, presentation of essential characteristics and limitations of the treatment.

Material and methods

Treatment of skeletally immature patients up to 16 years old who had a lengthening nail inserted was retrospectively clinically and radiologically evaluated (2016–2018).

Results

A total of 60 procedures were performed on 54 patients. Mean age at the time of surgery was 13.6 years and the mean follow-up time was 10 months. Different nailing approaches were used: antegrade femoral (n?=?42), retrograde femoral (n?=?10) and antegrade tibial (n?=?8). The average amount of lengthening was 45?mm. In 58 of the 60 cases (96.7%) the desired amount of lengthening was achieved, while 2 patients experienced complications that required interruption of the treatment. None of the patients developed growth disorders associated with the nailing approach.

Conclusion

Different approaches for intramedullary lengthening nails can be used in children and adolescents to correct leg length discrepancy with or without concomitant deformities. The treatment is limited by the size of the available nails, the residual growth and extent of the deformity. Larger trials will be needed to further validate the application of lengthening nails in skeletally immature patients.

     

Gradual femoral lengthening with the Albizzia intramedullary nail

BACKGROUND: Gradual limb lengthening with currently used external fixation techniques can result in less than optimal outcomes, with complications including infection, stiffness of adjacent joints, and secondary axial deviation of the extremity. We describe a totally implantable lengthening device designed to provide results similar to those achieved with external fixation devices, with fewer complications and improved outcomes. METHODS: Between 1993 and 1997, thirty-one patients (forty-one femora) underwent limb lengthening with a new internal fixation technique (Albizzia) to treat a congenitally short extremity (thirteen patients), post-traumatic limb-length inequality (eleven patients), or developmental problems (seven patients). Twenty-one patients (twenty-one femora) underwent unilateral surgery to equalize the limb lengths, and ten (twenty femora) underwent bilateral surgery to correct short stature. The mean age was twenty years and one month (range, twelve to thirty-nine years). After intramedullary corticotomy of the diaphysis of the femur, an intramedullary nail was inserted in an antegrade fashion. Fifteen alternating internal and external rotation maneuvers of the lower limb elongated the nail by 1 mm. The outcomes were assessed clinically and radiographically at a mean of fifty months postoperatively. RESULTS: The gain in femoral length averaged 3.4 cm (range, 2 to 5.5 cm) after the unilateral lengthening procedures and 6.3 cm (range, 4.6 to 8.4 cm) after the bilateral procedures. Patients underwent an average of three operations on each limb; these procedures included, in addition to the nail insertion and nail removal, ratcheting under general anesthesia in thirteen limbs and eleven procedures to treat complications in nine patients. At the time of follow-up, no patient had axial deviation of the limb secondary to lengthening. CONCLUSIONS: Femoral lengthening with use of the minimally invasive Albizzia technique provides a reasonable alternative to external fixation that is well tolerated by patients and results in excellent function with little or no distortion of body image.     

Results of femoral lengthening over an intramedullary nail and external fixator

INTRODUCTION: Current techniques of operative limb lengthening usually are based on distraction osteogenesis. One of the techniques is limb lengthening over an intramedullary nail. AIM OF PAPER: The goal of this study is to evaluate the results of femoral lengthening over an intramedullary nail. MATERIAL: Between 1999 and 200619 femoral "over nail" lengthenings were performed. There were 7 males and 12 females. Mean patients' age at surgery was 15.8 years, and mean initial femoral shortening was 5.1 cm. Operative technique consisted of one-stage implantation of intramedullary nail and external fixator. Ilizarov apparatus was used in 9 patients, monolateral fixator in 10 cases--ORTHOFIX in 9 patients, Wagner fixator--in 1 patient. Intramedullary nail was locked proximally with screws or Schanz pins from external fixator. After distraction phase, external fixator was removed and distal locking screws were applied. METHODS: Evaluation criteria: obtained lengthening, time of external fixator, treatment time, healing index, external fixation index, range of motion in hip and knee joints and complications according to Paley. RESULTS: The mean lengthening was 4.6 cm, and mean distraction time was 66.6 days. Mean time of external fixation was 115.5 days, and external fixation index was 26.2 days for centimeter. Healing index was 36.9 days for centimeter. In cases with monolateral fixator, healing index did not differ with the whole group. During treatment 18 complications occurred, for a rate of 0.9 complication per segment. CONCLUSIONS: Lengthening over an intramedullary nail reduces the time of external fixator. Over nail femoral lengthening can prevent axis deviation following regenerate bending. Complication rate is similar to lengthenings with the classic Ilizarov technique. There are no differences in the treatment time in relation to the type of external fixator.     

Promises and difficulties with the use of femoral intra-medullary lengthening nails to treat limb length discrepancies

Limb lengthening using external fixation may be associated with problems such as pin-track infections, poor patient acceptance, muscle transfixation, secondary axial deformity and re-fractures. Intramedullary lengthening nails have been designed to address these issues. We present our results for femoral limb lengthening in adults managed by intramedullary lengthening nails. A retrospective review was undertaken for 8 femoral lengthening procedures performed in adults using intra-medullary lengthening nails over a three-year period. The average age of our patients was 34 years; the average duration of follow-up was 26.5 months (range: 8 to 40 months). An Albizzia nail was used in 5 procedures, an Intra-medullary Skeletal Kinetic Distractor (ISKD nail) in 3 procedures. Target lengthening was achieved in 6 out of 8 femurs with an average of 38.77 mm (range: 0 to 70 mm) length gained. The distraction index (length gained per day) was 0.58 on average (range: 0-1.25) and the consolidation index average was 5039 (range: 0-79) days/cm. Premature consolidation was noted in 4 cases, runaway acute lengthening in one patient; prominent metalwork--noted in 4 patients--and a bent nail were frequent obstacles and meant multiple visits to theatre. Femoral lengthening with an intramedullary lengthening nail is a reasonable alternative to external fixators, thereby avoiding problems associated with callotasis using external fixation methods. It is however, important to counsel patients regarding possibilities of significant obstacles including failure and multiple visits to theatre during the process.