Leif Pål Kristiansen

Lengthening of the tibia over an intramedullary nail, using the Ilizarov external fixator : Major complications and slow consolidation in 9 lengthenings

We lengthened 9 tibial segments over a nail to reduce the time in the external fixator in 5 patients with constitutional shortness. The median lengthening was 7 (5.5-7.3) cm and the external Ilizarov frame was removed after median 99 (63-125) days. In spite of a short time in the external fixator, consolidation was slow, with a median lengthening index of 4.4 (2.4-6.1) months/cm. The procedure resulted in 3 fatigue fractures of the intramedullary nail or interlocking screws that needed revision and bone grafting. In 1 patient, a deep intramedullary infection occurred. After the experience of these major complications we have returned to the traditional callotasis lengthening method described by Ilizarov.

No difference in tibial lengthening index by use of Taylor Spatial Frame or Ilizarov external fixator

Background Different methods and devices are used to perform lengthening and deformity reconstruction in the tibia. Recently, the Taylor spatial frame (TSF) has been introduced as a computer-assisted and versatile external ring fixator. Lengthening index (LI) and complications are important result parameters, and the aim of this study was to review our first 20 tibial segments operated with the TSF and to compare the results with our experience of using the traditional Ilizarov external fixator (IEF). Patients and methods We lengthened 20 tibial segments in 20 patients with the TSF. The results were compared with those of 27 tibial segments from 27 patients that were lengthened with the IEF. All segments were operated on with monofocal osteotomies. Results In the overlapping zone of comparable lengthening distances between 2.4 and 6.0 cm, the LI of 2.4 and 1.8 months/cm was not significantly different between the TSF and IEF groups, respectively (p = 0.17). This non-significant difference was confirmed after adjustment for age. Interpretation We found no difference between the TSF and IEF frames regarding LI and complication rate. However, rotational, translational, and residual deformity correction is easier to perform with the TSF.

Residual challenges after healing of congenital pseudarthrosis in the tibia.

The purpose of the current study was to evaluate the clinical results of the Ilizarov bone transport method in the treatment of congenital pseudarthrosis in the tibia. In seven patients operated on between 2.6 and 7.8 years of age, primary healing of the pseudarthrosis was achieved in all patients (after additional bone grafting in two patients). Within a followup of 6 to 8 years, major complications occurred in all patients. Five refractures occurred, and in one patient the refracture did not heal. At the last followup, axial deformities and an abnormal malalignment test with lateral mechanical axis deviation of 10 mm or greater was found in all patients. Three patients had leg length inequality of 20 mm or more. The Ilizarov bone transport method is useful in achieving primary healing in congenital pseudarthrosis of the tibia, but residual challenges with secondary reconstructive surgery caused by refracture and postoperative deformities must be expected.

The normal development of tibial torsion.

Abstract.Objective:Pathological rotation of the leg is a well-known problem in paediatric orthopaedics. In this study the normal development of tibial torsion during growth was evaluated by computed tomography (CT). Design: Seventy-eight normal individuals (52 children, 26 adults) aged 3–51 years were examined with CT. In axial scans the angle between a line tangential to the posterior part of the femoral condyles and the intermalleolar line, a line through the centre of the lateral and medial malleolus, was measured. The radiation exposure was evaluated and accepted by The National Department for Radiation and the Regional Committee for Ethics in Science. Results: CT showed that the average lateral torsion of the leg at the age of 4 years was 28° with an individual variation of 20°–37°. Later the increase in tibial torsion was on average 1°/year until 10 years of age and, thereafter, 4° until maturity when the mean lateral torsion was 38° (18°–47°). Conclusion: Tibial torsion in children mainly develops during the first 4 years of life. After this the increase was of less clinical significance.

Reduced tibial torsion in congenital clubfoot: CT measurements in 24 patients

We determined leg torsion with CT scans through the femoral condyles and the ankle joints in 24 children (17 boys) with congenital clubfoot. In 16 cases, there was a bilateral clubfoot, in 5 cases it was left-sided and in 3 cases, it was on the right side. These children were compared to 17 healthy boys and 7 girls. The ages of all children ranged between 3 and 12 years. The average external torsion of the leg in the patients with clubfoot was 20 (15) versus 31 (7) degrees in the healthy children (p = 0.002). This study shows that there are great variations in leg torsion in children with congenital clubfoot and, on average, the external torsion is significantly lower than in healthy subjects.

High frequency distraction improves tissue adaptation during leg lengthening in humans

The present study investigates the effect of distraction frequency on the development of tensile force in the tissues during lengthening. Two patients with bilateral Ilizarov leg lengthening underwent distraction with high frequency in one leg and low frequency in the other. The clinical situation represented a unique model for investigating the effect of distraction frequency, as each individual served as its own control. Both patients had double level lengthening. Distraction frequency at the proximal lengthening zone was 0.25 mm × 4 in the first leg and 1/1440 mm once every minute in the other. Total diurnal distraction at the proximal metaphysis was 1 mm in both legs. In addition, a distal metaphyseal distraction of 0.25 mm × 3 daily was performed on each leg. The tissues mechanical response was monitored by measuring the tensile force at the proximal osteotomy. Both patients experienced a significant lower level of force during the high frequency lengthening. The lower level of force was concluded to be due to improved soft tissue adaptation, rather than reduced bone regeneration. Accordingly, high distraction frequency was considered favourable to low frequency, and is recommended in large lengthenings where high force levels are expected.

Reduced lengthening index by use of bifocal osteotomy in the tibia: Comparison of monofocal and bifocal procedures with the ilizarov external fixator

We lengthened 63 tibial segments in 49 patients, performing a monofocal osteotomy on 31 segments and a bifocal osteotomy on 32 segments. In the monofocal osteotomy group, the average lengthening was 4.8 (2.4-7.1) cm with a lengthening index (LI) of 1.7 (0.9-4.4) months/cm. In the bifocal osteotomy group, the average lengthening was 7.4 (4.9-10.0) cm and with a LI of 1.0 (0.7-2.1) months/cm. The difference in LI between the groups was statistically significant, but more major complications, like persistent ankle joint contracture and pseudarthrosis in the callotasis lengthening zone, occurred with bifocal lengthening.

Tissue response during monofocal and bifocal leg lengthening in patients

The purpose of this investigation was to compare the tissue response during mono‐ and bifocal limb lengthening. The study includes four patients undergoing leg lengthening. All patients started out bifocally with a total diurnal distraction of 1.75 mm, but proceeded monofocally with a rate of 1 mm a day when the distal distraction was terminated due to contractures or pain. The tissue response was monitored by registration of axial force in the distraction rods. The force increased linearly during bifocal lengthening, but culminated or decreased in the period of monofocal lengthening. Average tissue stiffness, defined as the immediate force increase due to each 0.25 mm distraction increment, was significantly higher in the bifocal lengthening phase. The force decay between each distraction was significantly lower during bifocal lengthening, thus indicating decreased tissue accommodation. Details in the force registrations indicated that the soft tissue, not the regenerate, was the main contributor to the tensile force. Conclusively, the tissues at the two osteotomy sites do not lengthen independently. Bifocal lengthening exposes the entire soft tissue to large loads, resulting in increased tissue stiffness and reduced ability to adapt to the increased length. Accordingly, bifocal leg lengthening requires special attention to soft tissue adaptation.

Ultrasonography of the infant hip: the significance of provokable instability with normal morphology.

The hips of infants 2- to 4-weeks-old were investigated with ultrasonography. In all cases, ultrasonography verified morphologically normal hips; however, either a bilateral or unilateral instability of the hip could be provoked as demonstrated by ultrasonography. The first series of 27 infants (41 hips) were treated with abduction splint (Frejkas pillow) for 16 weeks. The second series of 28 infants (44 hips) were left untreated. All infants had repeat ultrasonography at 2 and 16 weeks and radiographs at 16 weeks. At 2 weeks, provokable instability was still seen in 10 hips in the treated group and 12 hips in the untreated group. At 16 weeks, all hips were ultrasonographically stable. The morphology was evaluated by alpha and beta angles by ultrasonography and also acetabular index by radiographs at 16 weeks. In all cases, normal hip development was noted with no differences between the two groups. Therefore, sonographically, instability in morphologically normal or immature hips has no clinical significance.

Negative correlation between extent of physeal ablation after percutaneous permanent physiodesis and postoperative growth: Volume computer tomography and radiostereometric analysis of 37 physes in 27 patients

Background and purpose Percutaneous physiodesis in the knee region is a well-established method for treating leg-length inequality. Longitudinal growth in the physis is believed to stop almost immediately after the operation. The extent of physis ablation required has never been investigated by any kind of tomography in humans. Using radiostereometric analysis (RSA), we determined when definite growth arrest occurred after surgery. We also studied the correlation between the extent of physis ablation and postoperative growth. Finally, we assessed any bone bridging across the physis. Methods 6, 12, and 30 weeks after surgery, we used RSA to measure longitudinal growth in 27 patients (37 physes) with a mean age of 13 years. CT scanning of the knee region was performed 12 weeks after surgery to measure the percentage of the ablated physis and to determine the distribution of bone bridges across the physis. Results RSA showed that growth rate was reduced to less than half of the expected rate after 6 weeks. During the next 6 weeks, the growth ceased completely. CT scans revealed a large variation in the extent of ablated physes (17–69%). In the ablated areas, tissues of various densities were mixed with mature bone. Bridges were found both laterally and medially across the physes in all of the patients. There was a negative correlation between the extent of ablation and total postoperative growth (rho = –0.37, p = 0.03). Interpretation Growth across the physis is effectively stopped by percutaneous physiodesis. RSA is well-suited for observation of this phenomenon. Volume CT scanning can be used to detect bone bridges that cross the physis and to calculate the extent of physis ablation.