Sebastian Farr

Treatment of Varus Deformities of the Lower Limbs in Patients with Achondroplasia and Hypochondroplasia

Angular deformities of the lower limbs are a common clinical problem encountered in pediatric orthopaedic practices particularly in patients with osteochondrodysplasias. The varus deformity is more common than the valgus deformity in achondroplasia and hypochondroplasia patients because of the unusual growth of the fibulae than that of the tibiae. We retrospectively reviewed six patients (four patients with achondroplasia and two patients with hypochondroplsia) with relevant limb deformities due to the above-mentioned entities. All patients manifested significant varus deformity of the lower limbs. Detailed phenotypic characterization, radiologic and genetic testing was carried out as baseline diagnostic tool. We described the re-alignment procedures, which have been applied accordingly. Therefore, bilateral multi-level procedures, multi-apical planning and limb lengthening have been successfully applied. While recognition of the underlying syndromic association in patients who are manifesting angular deformities is the baseline for proper orthopaedic management, this paper demonstrates how to evaluate and treat these complex patients.

Functional and radiographic consideration of lower limb malalignment in children and adolescents with idiopathic genu valgum

Three‐dimensional gait analysis is capable of assessing dynamic load characteristics and the resulting compensatory effects of lower limb malalignment, which are generally not reflected in static imaging. This study determined differences in gait parameters in the frontal and transverse plane between patients and controls in order to identify compensatory mechanisms, and to correlate radiographic measurements and gait parameters in a consecutive series of children with idiopathic genu valgum. Thirty‐three patients (mean age 12.3 years) were retrospectively reviewed and compared to a healthy control group. Children with genu valgum demonstrated significantly decreased internal knee valgus moments, shifting into varus moments. Furthermore, significantly different transverse plane gait patterns (decreased external knee rotation, increased external hip rotation) were observed. These patterns showed a relevant influence on the frontal knee moments, with knee rotation and foot progression angle showing the highest predictive value for changes and possible compensation of frontal knee moments. The correlation between commonly used radiographic measurements (i.e., mechanical axis deviation) and findings of the gait analysis was only low. Besides showing decreased internal knee valgus moments, our results suggest that considerable compensatory gait mechanisms may be present in children with idiopathic genu valgum to reduce joint loading.

Radiographic Early to Midterm Results of Distraction Osteogenesis in Radial Longitudinal Deficiency

PURPOSE To analyze early to midterm radiographic results after forearm lengthening in children with radial longitudinal deficiency. METHODS We conducted a retrospective chart review of patients with radial longitudinal deficiency undergoing distraction osteogenesis with an Ilizarov device. We retrospectively reviewed 8 lengthening procedures in 6 children with respect to distraction details and assessed anteroposterior and lateral radiographs of the hand and forearm of the preoperative and postoperative follow-up investigations. RESULTS The mean age at time of ulna lengthening was 9.9 years (range, 6.3-14.0 y). The mean follow-up period was 4.7 years (range, 1.0-8.5 y). Mean lengthening of the ulna was 7.0 cm (range, 3.5-8.7 cm), and the mean length gain of the ulna compared with its preoperative length was 75% (range, 42% to 103%). The mean ulna bowing was 25° preoperatively (range, 7° to 42°), 6° after forearm distraction (range, 0° to 14°), and 17° at latest follow-up (range, 0° to 45°). The mean hand-forearm angle was 25° of radial deviation preoperatively (range, 15° ulnar to 60° radial deviation), 11° of radial deviation after distraction (range, 0° to 41°), and 23° at latest follow-up (range, 0° to 45°). We encountered 2 major complications: 1 ulna fracture after removal of the Ilizarov device and 1 insufficient bone regenerate during lengthening. CONCLUSIONS We achieved both deformity correction and improvement of limb length after distraction osteogenesis with an Ilizarov device. However, some of the deformity-in particular, ulnar bowing and radial deviation of the hand-recurred at midterm follow-up.

Open surgery versus nonoperative treatments for paediatric trigger thumb: a systematic review

The purpose of this systematic review was to determine the outcome of interphalangeal (IP) joint motion in children undergoing open surgical release, splinting, and passive exercising therapy for the treatment of paediatric trigger thumb. We conducted an online literature search of seven major databases. Only studies with a mean follow-up of at least 12 months were considered for inclusion. Seventeen retrospective studies and one prospective study met all the inclusion criteria. They reported on the results of surgery (634 children, 759 thumbs), splinting (115 children, 138 thumbs), and passive exercising (89 children, 108 thumbs). The mean follow-up periods were 59 (surgery), 23 (splinting), and 76 months (exercising), respectively. Full IP joint motion without residual triggering was achieved in 95% of all children undergoing surgery, in 67% of children treated with continuous splinting, and 55% after passive exercising. Based on the low level of evidence available, it seems that open surgery resulted in more reliable and rapid outcomes compared with nonoperative treatment.

Windswept lower limb deformities in patients with hypophosphataemic rickets.

BACKGROUND X-linked hypophosphataemic rickets is an X-linked dominant disorder that is secondary to renal phosphate-wasting. Genu varum and/or genu valgum have been described as the most common deformities in patients with hypophosphataemic rickets. Windswept deformity, which is valgus deformity in one knee and varus deformity in the other, was the most common deformity encountered in our department. PATIENTS AND METHODS We collected seven patients who had phenotypic and genotypic features consistent with the diagnosis of X-linked hypophosphataemic rickets. All presented with windswept lower limb deformity. We discuss the phenotypic and genotypic correlation, and the surgical procedures applied. Surgical interventions were scheduled to correct the triad of appearance, function and biomechanics. RESULTS Re-alignment orthopaedic measures were applied to correct and to restore normal growth and development in these children. Post-operative measurements showed dramatic improvements in balance and gait. CONCLUSION The most common deformity seen in patients with hypophosphataemic rickets is gradual anetrolateral bowing of the femur combined with tibia vara. Windswept lower limb deformity was the most common angular deformity in our patients with hypophosphataemic rickets. Baseline skeletal surveys and genotypic characterisation were subject to close scrutiny and assessment, with the aim of proper diagnosis and treatment. Nevertheless, recurrence of deformity is a common sequel and younger patients have a higher risk for recurrence.

Reconstruction for elbow instability caused by congenital aplasia of the ulnar coronoid process—a case report

A 13-year-old girl presented at our tertiary referral center with bilateral posterior radial head dislocation and aplasia of the ulnar coronoid process (Figure 1). She was pain-free, had a 30-degree lack of elbow extension, limited forearm pronation and supination (80–20 degrees on the right side, 80–0 degrees on the left side), but no signs of elbow instability. After several years without any relevant restrictions during her daily life activities, she returned to our outpatient clinic at the age of 17 with increasing pain on both sides and distinct radiological signs of posterior humeroulnar dislocation due to aplasia of the ulnar coronoid process (Figure 2). A review of the literature did not yield any information about that specific deformity or any possible treatment options. We decided to reconstruct the right elbow via an anteromedial approach, using a tricortical iliac crest bone graft as a coronoid equivalent and artificial bony restraint to the elbow joint.

Bone Lengthening in the Pediatric Upper Extremity.

➤Bone lengthening has been used successfully for several congenital and acquired conditions in the pediatric clavicle, humerus, radius, ulna, and phalanges.➤Common indications for bone lengthening include achondroplasia, radial longitudinal deficiency, multiple hereditary exostosis, brachymetacarpia, symbrachydactyly, and posttraumatic and postinfectious growth arrest.➤Most authors prefer distraction rates of <1 mm/day for each bone in the upper extremity except the humerus, which can safely be lengthened by 1 mm/day.➤Most authors define success by the amount of radiographic bone lengthening, joint motion after lengthening, and subjective patient satisfaction rather than validated patient-related outcome measures.➤Bone lengthening of the upper extremity is associated with a high complication rate, with complications including pin-track infections, fixation device failure, nerve lesions, nonunion, fracture of regenerate bone, and joint dislocations.

Radiographic Criteria for Undergoing an Ulnar Shortening Osteotomy in Madelung Deformity: A Long-term Experience From a Single Institution.

Background: There are no established guidelines on the age or the severity of deformity for which an ulna shortening osteotomy or ulna epiphysiodesis should be performed in children and adolescents with Madelung deformity. The purpose of this study was to identify radiographic criteria associated with the eventual performance for an ulna shortening procedure in this patient population. Methods: We retrospectively identified 41 wrists in 31 Madelung patients (mean±SD age 13.8±3.2 y) subjected to surgical correction of their deformity between 1999 and 2013. We assessed established radiographic criteria (ulnar tilt, lunate subsidence, palmar carpal displacement, ulnar variance) at preoperative and postoperative visits. Univariate and multivariate analyses were carried out to determine which radiographic criteria were associated with the performance of an “ulnar shortening procedure” at the first (index) surgical procedure. Results: Eleven wrists were subjected to an ulna shortening osteotomy at the index and 5 at subsequent procedures; 10 cases received an ulnar epiphysiodesis (mean age 13.4±1.5 y). Ulnar shortening at the index procedure was associated with significantly higher preoperative lunate subsidence, ulnar variance, and palmar carpal displacement. Ulnar variance of >5 mm and lunate subsidence >4 mm resulted in a respective 67% and a 53% likelihood of undergoing ulnar shortening osteotomy; palmar carpal displacement over 22 mm resulted in a 50% likelihood for ulnar shortening. Patients who required a subsequent procedure (n=8) showed a significant increase in palmar displacement between surgeries. None of the 10 cases with a primary ulnar epiphysiodesis received a subsequent ulnar shortening; none of those undergoing late ulnar shortenings had an ulna epiphysiodesis at their index procedure (at 10.3±4.3 y). Conclusions: Lunate subsidence, ulnar variance, and palmar carpal displacement were significant radiographic criteria for undergoing an ulnar shortening osteotomy at our institution. A shortening osteotomy may be prevented by early ulna epiphysiodesis in skeletally immature children older than 10 years of age. Level of Evidence: Therapeutic level IV—case series.

Rebound of Frontal Plane Malalignment After Tension Band Plating

Background: Despite the popularity of tension band plating (TBP) current literature lacks clinical data concerning recurrence (“rebound”) of frontal plane malalignment. This study investigated the rebound phenomenon after TBP in idiopathic genu varum/valgum deformities. We analyzed factors that may contribute to the development of rebound after removal of TBP. Methods: Patients who had correction of idiopathic valgus or varus deformities by TBP at the distal femoral and/or proximal tibial growth plate were selected from a prospective consecutive database. Only patients who had plates removed for at least 1 year and had a long standing radiograph of the lower limbs before plate removal were included. Patients who had presumably not yet reached skeletal maturity (age under 14 y for girls and under 16 y for boys) were excluded. The change of the mechanical axis from plate removal to follow-up after skeletal maturity was evaluated and a statistical analysis was performed. Results: Twenty-nine patients (64 extremities) were eligible. The mean follow-up was 39.1 months (range, 12.3 to 67.3 mo). The mean mechanical axis deviation (MAD) was +0.8 mm (range, −26 to +22 mm) after plate removal and −2.4 mm (range, −29 to +27 mm) at follow-up, accounting for a significant change of MAD (P=0.046). We observed a mean, relative recurrence of frontal plate malalignment into valgus direction of −3.2 mm (range, −48 to +23 mm). Twenty extremities (31%) showed <3 mm of MAD change; 27 extremities (42%) showed >3 mm of MAD change into valgus, and 17 extremities (27%) >3 mm of MAD change into varus direction. Patients with <3 mm MAD change had only 0.8 years, and those >3 mm a mean of 2.0 years of remaining growth until skeletal maturity. Each additional m2/kg of body mass index increased the risk of valgus recurrence by 12.1%. The 3 genua vara patients revealed to have an even higher rate of malalignment recurrence (4 of 6 limbs) at final follow-up. Conclusions: Given our strict criteria, there is a high rate of radiologic recurrence of frontal plane malalignment after TBP. Children who are more than 1 year before skeletal maturity at TBP removal, and those with increased body mass index are at higher risk for rebound growth. Level of Evidence: Level IV—consecutive therapeutic case series.

A unique case of temporary epiphysiodesis in an adolescent patient with ulnocarpal impaction syndrome.

quantify cortical reorganization, we calculated Euclidean distances between the cortical source of the SEF and a fixed reference point that was selected based on magnetic resonance imaging (MRI) data. Euclidean distances were calculated using the following formula (√(∆ x)2 + (∆ y)2 + (∆ z)2) (Wiech et al. 2000). Cortical somatotopy was identified on three-dimensional brain surface images reconstructed from MRI data. The cortical sources of SEFs from the intact thumb were similar across the three time points. Euclidean distance was 60.6 mm at 7 weeks, 60.8 mm at 24 weeks and 59.6 mm at 42 weeks. However, the transplanted thumb showed remarkable cortical reorganization. Euclidean distance in the affected side was 58.0 mm at 7 weeks, 60.3 mm at 24 weeks and 67.7 mm at 42 weeks, and dipole strength values increased. In contrast, hand sensibility of the transplanted thumb showed no remarkable change over time (4.31-diminished protective sensation, purple) (Figure 1). Our major finding is that the SI cortical representation of the transplanted thumb moved more medially and more superiorly at 24 and 42 weeks than at 7 weeks after surgery, indicating SI cortical plasticity, but there was no parallel change in the results of S–W test. After digit amputation, SI cortical representation of adjacent intact digits enhanced at the expense of the amputated digit cortical region, and progression in the nerve regeneration process results in increased peripheral sensory inputs and this enables the transplanted thumb to restore more of its original SI cortical region (Wiech et al., 2000). The cortical plasticity in our case may show the same condition. The normal thumb has lower current perception threshold than normal toe (Chu, 1996), and the recovery in the S–W test of the replanted digit would be much better than that of toe-to-digit transplantation (Hirasawa et al., 1985). SEFs responses after nerve repair depend on nerve regeneration progression rather than skin reinnervation (Wiech et al., 2000). Therefore, we assumed that cortical re-organization observed by magnetoencephalography could be a finer indicator for the nerve regeneration process than the S–W test. The difference in the cortical source of SEFs from the transplanted thumb and the intact thumb at 42 weeks might be owing to inter-hemispheric differences in hand representation in the SI. A previous report has indicated that the cortical source of median nerve stimulation is located more medially in the left SI hemisphere than in the right SI hemisphere (Jung et al., 2008). In conclusion, SI cortical reorganization for the transplanted thumb continued even though the S–W score remained unchanged. Conflict of interests