Depending on the reference, pin track infection rates in external fixation surgery have been stated to be anywhere from 0% to 100%. We critically evaluated the pin track infection rate for external fixation by performing systematic review of the external fixation literature since 1980. Using PubMed, a search of the peer-reviewed literature on external fixation was performed. This systematic review was conducted, as much as possible, in accordance with PICOS and PRISMA guidelines. A total of 150 articles were reviewed, including at least one from each year between 1980 and 2014. The following data were collected from each article: the year of publication, number of patients in the study, average age of the patients, reason for the external fixation, fixation per segment (two or more than two points), body part involved, whether or not hydroxyapatite-coated pins were used, duration of the external fixator, type of fixator used, and number of patients with documented pin track infections. These 150 studies represented 6130 patients. There were 1684 reported pin track infections from these 6130 patients, giving a cumulative pin track infection rate of 27.4%. A more recent year of publication was associated with an increasing infection rate (P = 0.015) while increasing age was associated with a decreased infection rate (P < 0.0005). There were trends toward association of humerus location (P = 0.059), shorter fixator duration (P = 0.056), and circular fixation (P = 0.079) with decreased infection rates. This systematic review of external fixation publications revealed a cumulative pin track infection rate of 27%. Younger age was the factor leading to increased pin track infection rates. Circular fixation trended toward being protective of pin track infection when usage was factored into the multiple regression analysis. Longer duration of fixation trended toward increased infection rate as expected. This data provides important base values for a common complication in external fixation treatment, highlights the importance of a more consistent definition of a pin track infection in future research, and identifies the pediatric population as the group at greatest risk.

Introduction: The SAFE Dualcore Universal Nail is an interlocking nail with an antibiotic cement core. We compared the clinical and radiological results with a standard interlocking nail for treating open fractures of the tibia. Materials and Methods: Prospective, controlled cohort trial, including thirty patients with open fractures of the tibia. Patients were divided into two groups according to the treatment method: Group I (STD), consisting of 14 patients treated by delayed interlocking standard nailing, after an antibiotic treatment and bed rest. Group II (SAFE) had 16 patients treated with an interlocking intramedullary nail with a core of polymethyl methacrylate cement with antibiotics. Five of these were temporarily stabilized with an external fixator. We added vancomycin (2 g) and flucloxacillin (2 g) to the bone cement in the core of the nail. The two groups were similar on demographic data (age, gender), fracture, and extent of the wounds (P > 0.05). The mean follow-up was 2.4 years (5 months to 4 years) for the STD group and 2.1 years (4 months to 3 years) for the SAFE group. Results: Fifteen of the 30 patients had positive cultures, including 13 cases growing Enterobacter, Enterococcus, Pseudomonas, and methicillin-susceptible Staphylococcus aureus (MSSA) groups. The infection rate was significantly more in STD at 43% (6/14 patients) compared to SAFE 6% (1/16 patients), (P = 0.02). Healing times was significantly more for STD group, at an average of 7.5 months (3-18 months) compared to 4.5 months (2-8.5 months) for the SAFE group (P = 0.02). The complication rate was 64% (9/14) in the STD group and 25% (4/16) for the SAFE, including the infection rate, a statistically significant difference (P = 0.03). The six infected STD nailing cases were salvaged with antibiotic coated cement nails, five of which healed. Infection recurred in the sixth case and was treated with the Ilizarov method. Conclusion: SAFE nails had lesser infection, faster consolidation, and fewer complications compared with standard nails in treating open fractures of tibia. We can choose the type and dose of antibiotics eluted by the nail. The SAFE DualCore Universal nail is mechanical stable as well as biologically active. It allows fixation of intermediate bone segments, shortens hospital stay, healing time, and reduces the cost of treatment. Level of Evidence: Level III.

Introduction: Congenital pseudarthrosis of the tibia (CPT) is a rare condition that can pose a challenge in achieving union after surgical excision of the pseudarthrosis site. Multiple methods have been described for management of fractures complicating this abnormal bone, including intramedullary nails (IMNs) and external fixators. One of the IMN designs is the telescoping nail, which has many models including the Fassier-Duval (FD) rod. This system has been known for its use in the management of osteogenesis imperfecta and different types of dysplasia. In this series, we describe our experience with the use of this system in the management of CPT of the tibia in children. Methods: We conducted a retrospective chart review of four patients with FD rod insertions for CPT management. The mean age at surgery was 7.6 years (range: 1.5-17) and the minimum follow-up was 20 months (average: 52.3 months, range: 20-93 months). Two out of the four patients had a concomitant diagnosis of neurofibromatosis Type 1. Results: All four cases achieved union of the fracture at final follow-up. Complications encountered in these cases included a case of joint intrusion into the knee and a case of rod migration due to the failure of telescoping. Conclusion: The FD rod showed promising results in our cohort, but before this treatment modality can be recommended for the management of CPT, additional studies are required. Level of Evidence: IV

Context: Hexapod fixators can be divided into two basic design groups. One group consists of frames that use ball and socket joint struts attached to the outer surface of the rings. The other group consists of frames that use cardan type universal joint struts attached to the under surface of the rings. Aims: To compare the ability of different hexapod fixator systems for deformity correction. Settings and Design: Nearly, identical two-ring frame constructs were compared to determine if there was any difference in deformity correction capability between cardan type universal joint struts and ball and socket joint struts. Materials and Methods: Maximal deformity was created using the software for each of the frame constructs in all six planes of deformity (angulation, translation, and rotation in the coronal and sagittal planes). Clinical scenarios were also compared (equinus contracture, moderate Blount disease, and severe Blount disease) and the number of strut changes necessary to correct the deformity were recorded. Results: For the small and medium-sized struts, the angular deformity corrections were similar, but the cardan type universal hinges had a greater capability for correcting translational deformity and rotation than the ball and socket joints. However, the amount of lengthening possible was greater for the ball and socket joints with these strut sizes. In the largest size of struts, the ball and socket joints had greater range in every category except rotation. In patients requiring significant rotational correction, the cardan type universal joints were found to impinge on the soft tissues 13° earlier than the ball and socket joints (39° vs. 52°). A Blount disease case with moderate multiplanar deformity and an equinus correction of 45° required the same amount of strut changes for each design. For the Blount disease case with severe multiplanar deformity, the cardan type universal joint struts required six total changes, whereas the ball and socket joint struts required only one strut change and two strut adjustments to achieve the same correction. Conclusions: Both the cardan type universal joint and the ball and socket joint hexapod frame designs allow substantial multiplanar corrections to occur. In the smaller size struts, the cardan type universal joints allow more translation and rotation, whereas the ball and socket joints allow more length. For large rotational corrections and frames built with 90° of offset, the ball and socket joint design is better at avoiding soft tissue impingement. While both systems are comparable with mild to moderate deformity correction, the ball and socket joint design allows more correction with less strut changes for patients with severe deformity in our experimental construct.

Background: This study aimed to compare two techniques of syndesmotic fixation in terms of preventing lateral malleolus migration and ankle malalignment during tibial lengthening. Methods: Children who had tibial lengthening > 20 mm using Taylor Spatial Frame were included. Two techniques of syndesmotic fixation were evaluated: Transverse tricortical screws and oblique quadricortical screws. Radiographs, before frame application and at frame removal, were reviewed. Tibial length, angular deformity, distal tibiofibular index (DTFI), proximal tibiofibular index (PTFI), and lateral distal tibial angle (LDTA) were measured. Malhotra grades and duration of external fixation were also recorded. Eighteen patients (21 limbs) were identified (transverse screws in 15 limbs and oblique screws in 6 limbs). Age and gender were similar for both groups. There was no significant difference in lengthening amount (transverse: 40 mm and oblique: 35 mm), angular correction, lateral malleolar and fibular head migration, LDTA change, and frame duration. Results: After lengthening, and only in the transverse group, DTFI and PTFI changed significantly (DTFI pre: 12 mm, post: 8 mm, P = 0.01; PTFI pre: 17 mm, post: 22 mm, P = 0.02). Two ankles in the transverse group moved from Malhotra 0 to 1; however, no grade change was noted in the oblique group. No screw-related complications were encountered in either group. Conclusion: Although migration of lateral malleolus was encountered in the transverse group, the amount of DTFI change was similar to the oblique group and no LDTA change was noted in either group. No advantage of one syndesmotic fixation method over the other was found in this study.

Background: The purpose of this study was to investigate the agreement between the three-dimensional (3D) weight-bearing radiological measurements of leg deformities in the presence of leg rotation and knee flexion in a biplanar stereoradiography system (EOS imaging) and measurements of computed tomography (CT) scans. Methods: Upright biplanar X-rays of six Sawbones^; with deformity were registered in no flexion/rotation angle, in 10° and 20° of axial rotation, and 10° and 20° of knee flexion. A CT scan of each bone was registered in supine position, and the 3D reconstruction of each bone was generated. Two-dimensional (2D) lengths and deformity angles were measured on the plain X-rays by two independent observers. Two independent observers generated the 3D reconstructions of the biplanar X-rays and the leg deformity parameters were measured in 3D using custom-developed software. 2D and 3D measurements were compared to CT measurements performed by two observers and repeated three times. The intraclass correlation and limit of agreement between the three measurement techniques were evaluated using Bland-Altman plots. Results: The intraclass correlations were good to excellent for the three imaging modalities (intraclass correlation coefficients = 0.71-0.95). Frontal deformity angles and lengths were significantly different in the 2D X-rays and CT (P < 0.05) whereas all the length and deformity measurements were comparable between CT and 3D X-rays (P > 0.05). Conclusions: The 3D measurements of the weight-bearing biplanar X-rays were comparable to 3D CT in assessment of the lower limb deformity.

Context: The osseous and soft tissue anatomy of the knee in congenital longitudinal lower limb deficiencies is important to consider, both in limb lengthening procedures and in soft tissue reconstruction. Aims: Our study aims to further define the patho-anatomy of the knee in this group of patients. Methods and Material: 24 children were reviewed clinically and radiologically. Osseous and soft tissue anatomy is described including MR imaging of 27 affected knees. Results: Our results echoed those of previous authors, with dysplasia of the menisci and cruciate ligaments a frequent finding. However, the study demonstrated that a clear correlation between the osseous anatomy and soft tissue findings was not always seen. Conclusions: MRI allows assessment of the cartilaginous epiphysis in younger children with longitudinal dysplasia and we would recommend systematic assessment of the knee prior to any surgical intervention.

Osteoarthritis of the hip joint as a complication of limb length discrepancy (LLD) caused by lower extremity deformity is rarely reported in the literature. We report two such cases of osteoarthritic changes of the long leg hip joint due to severe LLD but no developmental dysplasia of the hip. Both underwent limb lengthening, and the symptoms were improved without further treatment. The osteoarthritic changes are secondary to functional acetabular dysplasia resulting in insufficient acetabular coverage of the femoral head and lateral inclination of the pelvis caused by LLD. Thus, lengthening treatment may be one option for such patients with osteoarthritis due to functional acetabular dysplasia.