Background

Several risk factors for the development of osteonecrosis following treatment of developmental dislocated hip have been reported. The need for further research with a large-enough sample size including statistical adjustment of confounders was demanded. The purpose of the present study was to find reliable predictors of osteonecrosis in patients managed for developmental dislocation of the hip.

Introduction: It has been proposed that rotational gait abnormalities in the normal child are usually reflections of the anatomic deformity. A decreased acetabular and femoral anteversion have been recognized as a predisposing factor for osteoarthritis of the hip and the McKibbin instability index was introduced to quantify this relationship. Additionally, an increased femoral anteversion has been associated with osteoarthritis of the knee. However, it is well known that compensatory factors influence the dynamic rotational profile during gait. We compared rotational computed tomography data with gait analysis to evaluate their correlation and to elucidate the influence of compensatory mechanisms.

Materials and Methods: In a prospective study conducted between 2001 and 2005 patients presenting with rotational malalignment were sent for 3D gait analysis. Main exclusion criterion was any kind of neurological affection. Patients in whom surgery was considered were referred to rotational computed tomography. The rotational alignment of the pelvis, hip and knee at different times during the gait cycle as evaluated in the 3D gait analysis was compared to the angular values derived from the rotational computed tomography for the femur and tibia and statistically analyzed and correlated.

Results: There were 12 female and 16 male patients with a mean age of 16 (± 9.7) years at the time of gait analysis. After a first evaluation of data 8 limb segments were excluded to increase the quality of data. The mean anteversion of the femur was 29 degrees (2 degrees of retrotorsion to 56 degrees of anteversion) and the mean tibial torsion was 31 degrees (1 to 66 degrees of external torsion). The calculation of the Pearson correlation showed that an increase of femoral anteversion resulted in an increase of pelvic range of motion. An increase of femoral anteversion resulted in an increase of the internal rotation of the hip. Highly significant correlations were found between the rotational–CT values for the tibia and the all parameters describing rotation of the knee. The determination coefficient was high for tibial torsion versus knee rotation (R2 = 0.64), but showed a low value for femoral anteversion versus hip rotation (R2 = 0.2).

Conclusion: The rotation of the hip as found in the gait analysis showed only weak correlation with rotational CT data. This is not surprising as the hips segment offers many possibilities for compensation. The torsion of the tibia was found to correlate very strongly with the gait analysis. The McKibbin index seems questionable as a prognostic factor for the individual patient in the light of a multitude of dynamic compensatory influences. Effort should be made to integrate the static instability index with dynamic gait analysis data.

Introduction: Temporary hemiepiphyseodesis allows correction of angular deformities of the lower extremities in children before the end of growth. The eight plate is an alternative to Blount staples with the theoretical advantage of a more minimal approach, less risk of loosening with subsequent need for a re-operation and less compression of the growth plate due to the tension band mechanism. We report our results and experiences with this new implant.

Methods: Between August 2005 and May 2007 we implanted 74 eight plates (Orthofix International NV, Netherlands Antilles) in 32 patients. An idiopathic valgus deformity was the indication in 20 patients, an idiopathic varus in 4 patients, and a malalignment due to other reasons like infection, syndrome-association or trauma was seen in 8 patients. For the first part of this study we evaluated intra–and postoperative complications in patients with a minimum follow-up after the operation of 3 months. For the second part of the study we evaluated the results of correction after removal of the plate and analyzed long-standing radiographs using the malalignment test.

Results: Twenty-three patients treated with a total of 52 eight plates were included into the first part of this study. The mean follow-up after implantation was 9,5 months (range:3,4–22 months). One patient suffered from a significant postoperative haematoma which resolved spontaneously after 2 weeks and two patients showed a limited range of motion of the knee joint postoperatively. In both patients the range of motion was completely restored after 10 sessions of physical therapy. No other complication was seen during follow-up. Up to now 25 eight plates in 12 patients with 18 lower limb segments were removed. The mean age of the patients at the time of surgery was 12,2 years(rang: 6 – 13). The x-rays of these 18 lower extremities were reviewed and the alignment was analyzed. The mean preoperative mechanical axis deviation was 30,6mm (range: 8-50 mm). After hardware removal the mechanical axis showed a mean deviation from the center of the knee joint of 0,2 mm medial (range: 6mm lateral to 5 mm medial). The mean duration of implantation was 8,3 months (range: 4 to 16 months). Overcorrection was found in 2 patients, while a lack of correction at the end of growth was seen in one patient.

Conclusion: The eight plate is a safe and effective implant for temporary hemiepiphyseodesis. Especially loosening or implant failure, both commonly reported with the use of Blount staples, was not seen in our case series. Due to the minimal invasive approach with the need to implant only one eight-plate vs. two to four Blount staples and the sizes of the plates available the indications may be spread to a wider spectrum of deformities and ages.

Introduction: Cases of developmental dislocation of the hip occur after walking age because of late or missed diagnosis and failed conservative or operative treatment. Up to now there is no consensus on the treatment of DDH after walking age. The purpose of this retrospective study was to evaluate the results of operative treatment in DDH after walking age in our patient population and to describe the treatment strategies and operative techniques used.

Material and Methods: Forty-two patients presenting 54 cases of DDH after walking age were operated on in our clinic between 1985 and 1997. There were 34 female and 8 male patients, with an average age at the time of operation of 47 months (range: 14 – 151 months). The parameters studied were the type of DDH according to Ts, the preoperative AC- angle, the postoperative AC- and CE- angles as well as the radiological outcome using the Severin classification.

Results: Based on the Ts classification we found 18 cases of type II, 22 cases of type III and 14 cases of type IV dislocations. Each hip had an average of 1.4 operations. The average preoperative AC- angle was 38.2 degrees (range: 22–50) whereas the average AC- angle in the last radiographic follow up was 22.2 degrees (range:5–10). The statistical analysis showed that the AC angle at the last follow up was significantly (p< 0,001) smaller than in the preoperative radiographs. The classification according to Severin showed class I in 28 cases, class II in 15 cases, class III in 8 cases and class V in 3 cases.

Conclusion: Although our study presents the results after a mid-term follow up the radiological results favor our clinical experience that a single stage combined procedure consisting of open reduction, pelvic osteotomy as well as a corrective osteotomy within the proximal femur with subsequent shortening should be recommended.

Introduction: The knee joint in congenital longitudinal deformities of the lower extremity shows a large variety of pathological findings. Valgus deformity is found in most cases and is described as being juxta- articular. To describe the true anatomic pathology we performed a radiographic analysis of the knee joint in congenital longitudinal deformities.

Patients and Method: Between 1985 and 2001 we treated 102 patients presenting with congenital longitudinal deformities. Inclusion criteria for this study were diagnoses of fibular hemimelia (FBH) and/or congenital femoral deficiency (CFD), an age between 5 and 16 years, unilateral affection and availability of long standing X-rays, whereas bilateral affection or previous operations on the lower extremities were defined as exclusion criteria. Twenty-four parameters were defined on the femur and tibia respectively and a nomenclature was created. The mean values including standard deviation were calculated and we statistically compared the parameters of the affected to those of the non-affected knee. Furthermore, MRI scans of the knee joint of 20 of these patients were evaluated.

Results: Thirty- nine patients (19 female, 20 male) met the inclusion criteria. The average age at the time of evaluation was 8.87 years (3.1 SD). A combined deficiency of femur and tibia was found in 35 patients. The predominant diagnosis was CFD in 13, fibular hemime-lia in 13 and fibular aplasia in 9 cases. The anatomic lateral distal femoral angle (ALDFA) measured 75.4° (2.5 SD) on the affected, and 81.6° (1.6 SD) on the non-affected knee. The lateral distal femoral metaphyseal angle of the affected side and of the non-affected side showed no significant difference. The distal lateral femoral epiphyseal width (DLFEW) was decreased in the affected limb compared to the non affected limb, whereas the distal medial femoral epiphyseal width (DMFEW) of the affected and non-affected side showed only a minor difference. In the tibia we found no significant difference between the variables for the medial proximal tibial angle (MPTA) and for the medial proximal tibial metaphyseal angle (MPTMA) of the affected and the non-affected limb. A significant difference was found between the proximal lateral tibial epiphyseal width of the affected and the non-affected side. Analysis of the MRI scans revealed aplasia of the anterior cruciate ligament in 18 cases and aplasia of the posterior cruciate ligament in 8 of the 20 cases. The defect of ossification of the lateral tibial epiphysis as seen in plain X-rays is visible in the MRI scans as cartilage anlage. (Only the most important findings are summarized)

Conclusions: In our patient population only four patients had FBH or CFD but 35 cases presented combined defects; we assume that the femur is affected to some extent in almost all cases of FBH. The hypoplasia was only found in the lateral aspects of femur and tibia and was primarily located within the femoral epiphysis. The metaphysis was not or only minimally affected in the evaluated longitudinal deficiencies. Awareness of sagittal instability, due to ACL and/or PCL aplasia, is necessary to avoid subluxation or dislocation when lengthening procedures are performed.

Introduction: Although well-recognized in adults, RSD is rarely diagnosed in children. Management is still controversial and includes, mobilization and physical therapy, spinal cord stimulation, transcutaneous electrical nerve stimulation, steroids, tricyclic antidepressants, anticonvulsants, non-steroidal anti-inflammatory drugs, injections of calcitonin, vasodilators and calcium channel blocker or alpha-sympathetic blocker. In this study, we describe the treatment of RSD in children using Iloprost, a pros-tacyclin analog that mimics sympathicolysis. We report our treatment regime, the clinical course, complications and the outcome in our first seven patients.

Patients and Methods: Seven female patients with a mean age of 9 years (6 to 11 years) suffering from reflex sympathetic dystrophy (RSD) stage II were included in this prospective study. Inclusion criteria were RSD stage II – III, an age between 4 to 12 years, no previous operative procedures and duration of symptoms for a minimum of 6 months. Diagnosis of RSD was based on the presence of neuropathic pain, such as burning, dysaesthesia, paresthesia, and hypalgesia to cold, and physical signs of autonomic dysfunction such as skin cyanosis, mottling, hyperhidrosis, edema and coldness of the extremity. Treatment regime consisted of two infusions of Iloprost (IlomedinÒ, Schering AG, Germany) administered over 6 hours on two consecutive days. Additionally, all patients underwent physiotherapy as part of their inpatient treatment and were offered psychological counselling.

Results: One day after the last infusion, all seven patients were free of pain and full weight-bearing was possible. The side-effects of Iloprost were a headache in all patients and vomiting in two patients. Two patients relapsed, one 3 months and one 5 months after primary treatment. These two patients received a second series of infusions and were again free of pain within two days. During a mean follow-up period of 30 months all patients remained asymptomatic.

Conclusion: These preliminary results indicate that the treatment of RSD with Iloprost in combination with psychological counselling is a safe and effective treatment regime. Infusion therapy is a non-frightening procedure which may be an important factor considering the possible psychogenic etiology of RSD in children. Additional psychological counselling helps patients and their parents to develop coping strategies which may help to avoid relapses.

Introduction: The Taylor Spatial Frame (TSF) is a circular external fixator based on a hexapod system consisting of two carbon fiber rings connected with six telescopic struts. In conjunction with a software program the TSF allows for correction of deformities in 6 axis. After completion of the computer generated distraction plan a residual program can be used to correct any residual malalignment. Although the TSF received marketing clearance in 1997 and is used in specialized centers around the world, there is, up to date, only one MEDLINE report of two cases treated with the TSF. We present the results of 48 cases of limb lengthening and/or deformity correction using the TSF frame.

Patients and Methods: Between June 1999 and Septem-ber 2002 we implanted a total of 102 Taylor Spatial Frames (TSF). Only cases with a minimum follow up of 6 months after removal of the frame were included in our retrospective study. Thirty-six patients with a total of 48 TSF fixators met the inclusion criteria. The 23 female and 13 male patients had a mean age of 16 years (range:4-49). Eleven cases showed a post-traumatic deformity,13 cases a metabolic, 9 a congenital, 8 a osteodysplastic deformity and 7 showed various underlying pathologies. Seven TSF frames were implanted on the femur, whereas the remaining 41 frames were applied to the tibia.

Results: In 25 cases lengthening was the main treatment goal and in 23 cases the TSF was applied for angular or rotational deformity correction. The mean lengthening achieved in the group of patients treated was 40 mm (range: 20-70) and a mean healing index of 52.73 days/cm (28-105). In the patients who were treated to correct a deformity, the mean healing index was 159.69 days/cm (88-276). The highest mean healing index (178.91 days/cm) was found in patients where a metabolic disease was the underlying pathology, whereas patients treated for congenital lateral longitudinal defects showed the lowest mean healing index (53.25 days/cm). Complications included a superficial pin infection occurred in 66.6 % of the cases. There was no case of deep infection . Further complications were temporary postoperative sensory disturbance in 2 cases, premature consolidation of the fibula requiring re-oste-otomy in 2 cases, femoral fracture after removal of the frame in one case and dislocation of the frame with the need to change the position of a pin in another case. There were no hardware associated complications. A residual program was generated in 15 cases, 3 cases needed 2 and one case 4 residual programs to achieve the desired correction.

Conclusion: The healing index varied widely within our patient population. We assume that the healing index is not applicable to the correction of angular or rotational deformities with a lengthening less than 2 cm. The possibility of performing residual correction in all axis without the need to change the frame setup is a main advantage of the TSF and is very time saving during follow up examinations. Preoperative frame assembly is easy and fast compared to the standard Ilizarov system. A computer printed day-by-day prescription of strut adjustments makes it easy for the patient to perform the distraction and augments patient compliance.