The relationship between medial meniscal subluxation and stress distribution pattern of the knee joint: Finite element analysis.

BACKGROUND: Degenerative changes of the knee joint and clinical follow-up after meniscal subluxation are well documented. In the current study three-dimensional (3D) finite element analysis (FEA) of human lower limb was used to investigate the effect medial meniscal subluxation on the loadings of the knee structures. METHODS: Apart from the reference model, a total of ten 3D models were created, according to amount of medial meniscal subluxation. ANSYS® 14 was used to analyze the stress/load distribution, that is to say the maximum equivalent stress (MES) (von Mises stress) on bones, cartilages, ligaments and menisci. MES was expressed as Newton/mm(2) = Megapascal (MPa). RESULTS: In a static and standing upright position the MES on all knee structures were evaluated in the reference model. Although MES increased in all structures with the increase of medial meniscal subluxation degree, tibia cartilage was found to be the most affected structure with an increase of 22.73-fold in the 10 mm subluxation model when compared with references values. CONCLUSION: This study showed that medial meniscus subluxation is associated with increased loadings on all knee structures especially the tibia cartilage. Also the degree of the medial meniscal subluxation correlates with distribution and the amount of loadings on tibia cartilage which may be a prominent feature of knee osteoarthritis.

Comparison of Semi-Invasive "Internal Splinting" and Open Suturing Techniques in Achilles Tendon Rupture Surgery.

The goal of the present study was to evaluate the semi-invasive "internal splinting" (SIIS) method for repair of Achilles tendon rupture relative to open repair with Krakow sutures. Efficacy was evaluated based on the clinical and functional outcomes, postoperative magnetic resonance imaging measurements, isokinetic results, and surgical complication rates. Functional measurements included the Thermann and American Orthopaedic Foot and Ankle Society (AOFAS) ankle scores, bilateral ankle dorsiflexion, and plantar flexion measurements. Magnetic resonance imaging was used to compare the bilateral length and thickness of each Achilles tendon. The isokinetic outcomes were evaluated using a Biodex System 3 dynamometer. Of the 45 patients meeting the inclusion criteria, 24 were treated by SIIS and 21 by the open Krackow suture technique. The mean follow-up time for all patients was 43.7 (range 6 to 116) months. In the SIIS group, patients returned to normal daily activities after 7.2 (range 6 to 8) weeks compared with 14.3 (range 12 to 15) weeks in the open surgery group. The AOFAS ankle scores were 93.5 (range 82 to 100) points in the open repair group and 96.2 (range 86 to 100) points in the SIIS group. The Thermann scores were 80.4 (range 53 to 91) points for the open repair group and 87.9 (range 81 to 100) points for the SIIS method. The mean Achilles length on the operated side measured using magnetic resonance imaging was 175.06 (range 110 to 224) mm and 177.76 (range 149 to 214) mm for the open surgery and SIIS groups, respectively. Sensory impairment in the territory of the sural nerve was identified in 1 patient immediately after SIIS surgery, although this defect had completely resolved within 12 months. SIIS yielded better outcomes relative to the open surgery group according to the isokinetic measurements. Taken together, these data indicate the SIIS method for Achilles tendon ruptures performed better in terms of both functional and objective outcomes compared with open surgery.

Assessment of Postoperative Tendon Quality in Patients With Achilles Tendon Rupture Using Diffusion Tensor Imaging and Tendon Fiber Tracking.

Although pre- and postoperative imaging of Achilles tendon rupture (ATR) has been well documented, radiographic evaluations of postoperative intratendinous healing and microstructure are still lacking. Diffusion tensor imaging (DTI) is an innovative technique that offers a noninvasive method for describing the microstructure characteristics and organization of tissues. DTI was used in the present study for quantitative assessment of fiber continuity postoperatively in patients with acute ATR. The data from 16 patients with ATR from 2005 to 2012 were retrospectively analyzed. The microstructure of ART was evaluated using tendon fiber tracking, tendon continuity, fractional anisotropy, and apparent diffusion coefficient values by way of DTI. The distal and proximal portions were measured separately in both the ruptured and the healthy extremities of each patient. The mean patient age was 41.56 ± 8.49 (range 26 to 56) years. The median duration of follow-up was 21 (range 6 to 80) months. The tendon fractional anisotropy values of the ruptured Achilles tendon were significantly lower statistically than those of the normal side (p = .001). However, none of the differences between the 2 groups with respect to the distal and proximal apparent diffusion coefficient were statistically significant (p = .358 and p = .899, respectively). In addition, the fractional anisotropy and apparent diffusion coefficient measurements were not significantly different in the proximal and distal regions of the ruptured tendons compared with the healthy tendons. The present study used DTI and fiber tracking to demonstrate the radiologic properties of postoperative Achilles tendons with respect to trajectory and tendinous fiber continuity. Quantifying DTI and fiber tractography offers an innovative and effective tool that might be able to detect microstructural abnormalities not appreciable using conventional radiologic techniques.

Can hyperbaric oxygen be used to prevent deep infections in neuro-muscular scoliosis surgery?

BACKGROUND: The prevalence of postoperative wound infection in patients with neuromuscular scoliosis surgery is significantly higher than that in patients with other spinal surgery. Hyperbaric oxygen has been used as a supplement to treat postsurgical infections. Our aim was to determine beneficiary effects of hyperbaric oxygen treatment in terms of prevention of postoperative deep infection in this specific group of patients in a retrospective study. METHODS: Forty two neuromuscular scoliosis cases, operated between 2006-2011 were retrospectively reviewed. Patients who had presence of scoliosis and/or kyphosis in addition to cerebral palsy or myelomeningocele, postoperative follow-up >1 year and posterior only surgery were the subjects of this study. Eighteen patients formed the Hyperbaric oxygen prophylaxis (P-HBO) group and 24, the control group. The P-HBO group received 30 sessions of HBO and standard antibiotic prophylaxis postoperative, and the control group (received standard antibiotic prophylaxis). RESULTS: In the P-HBO group of 18 patients, the etiology was cerebral palsy in 13 and myelomeningocele in 5 cases with a mean age of 16.7 (11-27 yrs). The average follow-up was 20.4 months (12-36mo). The etiology of patients in the control group was cerebral palsy in 17, and myelomeningocele in 7 cases. The average age was 15.3 years (8-32 yrs). The average follow-up was 38.7 months (18-66mo). The overall incidence of infection in the whole study group was 11.9% (5/42). The infection rate in the P-HBO and the control group were 5.5% (1/18), and 16.6% (4/24) respectively. The use of HBO was found to significantly decrease the incidence of postoperative infections in neuromuscular scoliosis patients. CONCLUSION: In this study we found that hyperbaric oxygen has a possibility to reduce the rate of post-surgical deep infections in complex spine deformity in high risk neuromuscular patients.

The use of intralaminar screws in patients with spinal deformity.

STUDY DESIGN: Retrospective study. OBJECTIVE: To demonstrate that intralaminar screws (ILS) can be used as supplements in spinal deformity surgery in the thoracic and lumbar levels in pediatric and adult patients. SUMMARY OF BACKGROUND DATA: Rigid posterior fixation of the spine is generally accomplished using pedicle screws, hooks, or wires. ILSs are useful tools when other spinal fixation techniques have failed or the bony anatomy precludes hook or screw placement. MATERIALS AND METHODS: All spinal deformity patients (primary/revision) operated between 2007 and 2011 were retrospectively reviewed. The patients with ILS were included in the study. The anteroposterior and lateral standing x-rays were evaluated in terms of preoperative and postoperative coronal and sagittal deformities. The number and level of ILS, intraoperative complications, and postoperative complications were noted. RESULTS: There were 20 patients (12 male and 8 female). The mean age was 21.75 years. The mean follow-up period was 17.4 months. Fifty-seven ILS were inserted. Seventeen screws were used in the uppermost to lowermost levels. Forty screws were used in the middle. There was 1 lamina fracture and screw pull out (1.75%). There were 3 canal violations (corrected intraoperative) and 2 instrument prominences which required implant removal. The mean preoperative/postoperative cobb angles were 78.5 degrees/27.8 degrees and the mean preoperative/postoperative kyphosis angles were 57.2 degrees/32.5 degrees, respectively. The loss of correction was 1.2 degrees. There were no neurological deficits and no instrument failures. CONCLUSIONS: ILS are safe and effective when used in deformity correction. However, biomechanical studies and randomized controlled trials are needed to conclude whether ILS will be considered a first-line technique, or will remain a technique for salvage situations.

Changes in the loading of tibial articular cartilage following medial meniscectomy: a finite element analysis study.

PURPOSE: Depending on the location and extent of the meniscectomy, loading on the tibial articular cartilage alters. The main purpose of the present study was to analyze the loading on the tibial articular cartilage following medial meniscectomy performed in various location and extent, as well as in the healthy knee, via finite element analyses on the solid models. METHODS: Totally, 11 finite element solid models, including the reference model, were created to investigate the effect of location (anterior, posterior, longitudinal) and extent of meniscectomy (25, 50, 75, and 100 %) on loading of tibial articular cartilage. RESULTS: Maximum equivalent stress of the tibial cartilage was measured 0.86 Megapascal in the reference model and increased approximately by 78 % in 25 % meniscectomy group, 177.9 % in 50 %, 473.8 % in 75 % meniscectomy group, and 752.6 % in total meniscectomy. When only the amount of meniscal tissue removed was considered ignoring the location of meniscectomy, no significant difference was found in the amount of tissue excised between 25 % meniscectomy and 50 % meniscectomy, as well as between 75 % meniscectomy and total meniscectomy. CONCLUSION: In all meniscectomy models, the loadings on tibial articular cartilage increased. Except total meniscectomy, the highest impact was observed in longitudinal 75 % meniscectomy. During the surgical treatment, the contributions of menisci on load absorption by increasing the tibiofemoral contact area must be considered. In fact, the increase in the rate of loading on tibial articular cartilage depends on according to type and amount of meniscectomy.

A minimally invasive technique for the reduction of calcaneal fractures using the Endobutton®.

Calcaneal fractures are very common injuries, and closed reduction-percutaneous pinning, open reduction-internal fixation, and primary arthrodesis are the procedures used in the surgical treatment of these injuries. The aim of surgical treatment is to restore the normal biomechanics of the Achilles tendon and rearfoot by anatomic reduction of the articular surfaces. Minimization of the soft tissue complications commonly associated with the open treatment of calcaneal fractures can be achieved using indirect closed reduction and Kirschner wire or screw-assisted minimally invasive percutaneous osteosynthesis methods. In the present report, we describe a technique for the treatment of calcaneal fractures associated with soft tissues that are at risk of complications and present the cases of 3 patients treated with indirect, minimally invasive reduction of comminuted calcaneal fractures with the Endobutton(®) fixation device. From our experience with this method, we believe it will be useful in cases of acute calcaneal fracture with pronounced soft tissue injury localized to the hindfoot.

Investigation of diode laser effect on the inactivation of selected Gram-negative bacteria, Gram-positive bacteria and yeast and its disinfection on wastewater and natural milk.

Disinfection can be accomplished by adding external chemical agents to kill harmful microorganisms or by removing them using membranes. However, most chemicals are toxic for humans and animals if it is consumed above a certain concentration. Likewise, membranes have fouling problems. The aim of this study is to investigate the effect of diode laser, which is an environmentally friendly application, on pathogenic microorganisms such as Escherichia coli (ATCC 10536), Staphylococcus aureus (ATCC 6538) and Candida albicans. To reveal the effect of diode laser on aforementioned, various parameters have been studied on how diode laser type, laser irradiation time, laser power density, laser penetration efficiency and biofilm inhibition affect microorganisms. As a result of the study, it was observed that the blue laser was more effective than red and green lasers, and the inhibition rates for 15 min at 0.36 W/cm2 laser power density were 65.9% > 34.52% > 43.63% for S. aureus, E. coli and C. albicans, respectively. After 30 min of blue laser irradiation, the microbial growth inhibitions were found as 85.39%, 41.18% and 54.55% for S. aureus, E. coli and C. albicans, respectively. The highest biofilm inhibition was 94.61% when S. aureus cells were exposed to blue laser irradiation for 60 min. The microbial growth kinetics on three microorganisms were tested by using at 0.54 W/cm2 laser power density for 28 h, and there were not observed any microbial development in microbial cultures. Moreover, blue laser irradiation was successfully disinfected wastewater and natural milk at 0.54 W/cm2 laser power density.

Effects of botulinum toxin A on fracture healing in rats: an experimental study.

INTRODUCTION: Fracture healing is a complex process influenced by intrinsic and extrinsic factors. The aim of the present study was to evaluate the effects of botulinum toxin (BTX) A on fracture healing. MATERIALS AND METHODS: Following the induction of bilateral standard closed femoral fractures and relative fixation in 18 Wistar albino rats, 8 IU of BTX A were injected into the right femoral region. After 28 days, all of the rats were sacrificed, the diameter of the callus was measured, and fracture healing was assessed by biomechanical and histopathologic evaluation. RESULTS: While an increase in biomechanical and histopathologic healing was noted on the side injected with BTX A, a decrease in callus diameter was observed. CONCLUSION: Botulinum toxin A administration increases the healing power in a relatively fixated fracture and decreases the callus diameter, just as if rigid fixation had been performed. The beneficial effect of BTX A on fracture healing might be associated with increased fixation rigidity.

Does the technique of lateral cross-wiring (Dorgan's technique) reduce iatrogenic ulnar nerve injury?

In this study we compared the results of patients with displaced supracondylar humeral fractures who had been treated with all lateral cross-wire and medio-lateral cross-wire fixation techniques. Only the 139 patients who were able to attend the final examination were included in the assessment. The patients were allocated retrospectively into two groups according to the pin configuration used. Group 1 comprised 75 patients, 60 male and 15 female, with a mean age of 7.5 years (range, 1.5-14 years). After closed reduction, fixation was achieved with crossed K-wires placed from the lateral condyle and lateral humerus towards the medial epicondyle. Care was taken so that the end of the K-wire passing from the lateral humerus did not protrude excessively at the level of the medial epicondyle. Group 2 comprised 64 patients, 54 males and ten females, with a mean age of 7.8 years (range, 2-13 years). After closed reduction, two cross-wires passed-one from medial and one from lateral. In group 1 there was no postoperative iatrogenic nerve damage whereas in group 2 iatrogenic ulnar nerve damage developed in six (9%) patients. On statistical evaluation, a significant difference was seen between the two groups. According to Flynn's criteria, there was no statistically significant difference between the two groups. In conclusion, the lateral cross-wire fixation technique may be a good choice in the treatment of paediatric supracondylar humerus fractures as it reduces the possibility of ulnar nerve damage and achieves the same level of stabilisation as medio-lateral fixation.

Giant mantle cell lymphoma in the soft tissue of the leg: rare presentation.

BACKGROUND: Mantle cell lymphomas are aggressive, mature B-cell neoplasms characteristically showing overexpression of cyclin D1. Although lymphadenopathy is the most common presentation, involvement of extranodal sites including bone marrow, peripheral blood, liver, gastrointestinal system, and Waldeyer ring is also seen frequently. Soft tissue localization is extremely rare. It has blastoid and pleomorphic subtypes associated with aggressive course. CASE DESCRIPTION: We describe a 74-year-old man who had been diagnosed 3 years previously with "mantle cell lymphoma-blastoid type" and presented 3 months ago with a giant mass in the right lower extremity that enlarged rapidly up to 15 cm in a few months. CONCLUSION: We present this rare presentation, which was evaluated in favor of hemangioma before biopsy, together with the data in the literature to emphasize the need for differential diagnosis, especially in cases with a clinical history.

Isolated pedicle screw instrumented correction for the treatment of thoracic congenital scoliosis.

STUDY DESIGN: Retrospective study. OBJECTIVE: To evaluate the radiologic results of fusion with segmental pedicle screw fixation in neglected thoracic congenital curves with a mean follow-up of 51.3 months (range: 24 to 108 mo). SUMMARY OF BACKGROUND DATA: Segmental pedicle screw fixation has been shown to be effective both in correcting and controlling the idiopathic spinal deformities. However, the choice of treatment modality is more controversial in neglected thoracic congenital curves of the aged. METHODS: Fourteen patients with thoracic congenital curves treated by segmental pedicle screw fixation and fusion were analyzed. The average age of the patients was 14.9 years (range: 10 to 25 y) at surgery. Deformity correction was achieved by compression of the convex deformity side with resection of apical 3 ribs. Radiologic analyses of coronal and sagittal plane included Cobb angles of the major compensatory curves, apical vertebrae translation, and sagittal Cobb angles, respectively. RESULTS: In the coronal plane, the preoperative mean major curve Cobb angle of 52.3 degree (range: 32.6 to 66.7 degrees) was corrected to 25.3 degree (range: 7.2 to 44.8 degree) and the mean compensatory curve Cobb angle of 23.6 degree (range: 10.3 to 34.8 degrees) was corrected to 15.9 degree (range: 5.7 to 30.6 degrees). The mean translation of apical vertebrae was 28.8 mm (range: 4.7 to 53.6 mm) before surgery and 15.5 mm (range: 2.4 to 41.3 mm) after surgery. In the sagittal plane, the mean preoperative and postoperative sagittal T5 to T12 angles were 34.8 degree (range: 16.5 to 44.7 degrees) and 27.3 degree (range: 10.4 to 43.5 degrees), respectively. The mean preoperative and postoperative sagittal T12 to S1 angles were 47.2 degree (range: 23.4 to 65.1 degrees) and 41.3 degree (range: 23.8 to 62.7 degrees), respectively. CONCLUSION: In the neglected thoracic congenital deformities of the aged, with posterior pedicle instrumented fusion, an acceptable correction can be achieved with relatively low morbidity.

Biomechanical comparison of double versus triple button reconstruction techniques in patients with acromioclavicular joint dislocation.

BACKGROUND: Although many techniques are used to treat the acromioclavicular (AC) joint dislocations, minimal invasive or arthroscopic coracoclavicular ligament reconstructions became popular recently. In this study, authors compared the biomechanical results of double versus triple button reconstruction techniques. METHODS: Three-dimensional solid modeling of the shoulder girdle was carried out using virtual finite element modeling. AC joint dislocation was applied to the reference model, and these models were repaired by double and triple button techniques, respectively. Maximum equivalent stresses on buttons and sutures as well as displacements and reaction forces on AC joint were evaluated. RESULTS: Triple button model was more stable during flexion and abduction when compared with double button technique. CONCLUSION: Mimicking conoid ligament has a crucial mission more particularly against resistance during frontal plane actions, but the absence of the trapezoid ligament causes increasing the posterior displacement of the distal clavicle during the flexion of GH joint.

Evaluation of thoracic pedicle screw placement in adolescent idiopathic scoliosis.

Pedicle screw fixation is a challenging procedure in thoracic spine, as inadvertently misplaced screws have high risk of complications. The accuracy of pedicle screws is typically defined as the screws axis being fully contained within the cortices of the pedicle. One hundred and eighty-five thoracic pedicle screws in 19 patients that were drawn from a total of 1.797 screws in 148 scoliosis patients being suspicious of medial and lateral malpositioning were investigated, retrospectively. Screw containment and the rate of misplacement were determined by postoperative axial CT sections. Medial screw malposition was measured between medial pedicle wall and medial margin of the pedicle screw. The distance between lateral margin of the pedicle screw and lateral vertebral corpus was measured in lateral malpositions. A screw that violated medially greater than 2 mm, while lateral violation greater than 6 mm was rated as an "unacceptable screw". The malpositions were medial in 20 (10.8%) and lateral in 34 (18.3%) screws. Medially, nine screws were rated as acceptable. Of the 29 acceptable lateral misplacement, 13 showed significant risk; five to aorta, six to pleura, one to azygos vein and one to trachea. The acceptability of medial pedicle breach may change in each level with different canal width and a different amount of cord shift. In lateral acceptable malpositions, the aorta is always at a risk by concave-sided screws. This CT-based study demonstrated that T4-T9 concave segments have a smaller safe zone with respect to both cord-aorta injury in medial and lateral malpositions. In these segments, screws should be accurate and screw malposition is to be unacceptable.

Trevor's disease: up-to-date review of the literature with case series.

Trevor's disease, also known as dysplasia epiphysealis hemimelica, is a rare nonhereditary skeletal development disorder that affects epiphyses. This type of dysplastic lesion was first reported by Mouchet and Berlot in 1926 under the name 'tarsomegaly'. The main aim of this study is to raise awareness of Trevor's disease among orthopedic surgeons and underline some important aspects of treatment by a detailed presentation of four different possible manifestations of the disease. Four different treatment methods were used on four different patients (three localized in hindfoot ankle region and one classic Trevor's disease case). Treatment methods, localization of the sides involved, different characteristics of entire lower extremity, asymetry, distal femoral lateral epiphysis involvement, and hip involvement were analyzed thoroughly and the results were compared with those found in the most recent literature. Of our four patients, three were localized (hind foot ankle) cases and one was a classic dysplasia epiphysealis hemimelica with hemimelic distribution of the entire lower extremity. We used arthroscopic resection, observation, excision, and temporary hemiepiphysiodesis treatment methods in each of our cases. Clinical follow-up results were reported to be between good and excellent. In sum, our opinion is that the treatment for this condition should be customized according to lesion localization and lesion size. Majority of cases with ankle involvement show good prognosis following excision. Observation is also an alternative in patients who refuse surgery. If an intra-articular lesion is present, the surgeon should perform an arthroscopy for assessment of lesion surface. If the lesion is adapted to the joint curvature, it should be left alone and hemiepiphysiodesis should be considered for correction. The most risky involvements that are related to deformities and limb-length discrepancies are the hip and the knee. This is usually the result of corrective osteotomy targeted at the supracondylar femoral area in immature skeletons. Hemiepiphysiodesis might be a more feasible option in those cases as it provides the surgeon with the choice to remove the staples when necessary.

Arthroscopic fixation with intra-articular button for tibial intercondylar eminence fractures in skeletally immature patients.

The aim of this study was to describe our experiences with arthroscopy-guided intra-articular button fixation in the treatment of displaced tibial eminence fractures in skeletally immature children. Eleven adolescent patients with an average age of 12.2 years were treated arthroscopically between January 2005 and February 2007. At follow-up evaluation at 69 months, we did not find any instability. Only minimal differences were found in the functional outcomes (Lysholm and International Knee Documentation Committee scores: 95.7 and 94.3, respectively). None of the patients had a leg-length discrepancy defined at the time of the final follow-up. The advantages of this technique are as follows: (a) it is a simple and reliable arthroscopic technique with a direct view, (b) the fixation is stable,

Changes in the loadings on the shoulder girdle in the case of scapulothoracic fusion.

BACKGROUND: Scapulothoracic fusion (STF) may be an alternative and salvage procedure in the treatment of scapular winging. The biomechanical effects of this procedure on the shoulder girdle have not been previously considered. The purpose of this study is to demonstrate the relationship between STF and the stress distribution pattern of the shoulder girdle. METHODS: Three-dimensional solid modeling of the shoulder girdle was carried out using virtual finite element modeling. STF was applied to the reference model obtained in a computer environment. Dynamic and nonlinear analysis was performed. RESULTS: Stress distributions in joints and ligaments were calculated. With respect to loading on the joints, maximum equivalent stresses increased on acromioclavicular (AC) and GH joints in the case of STF during abduction and flexion respectively. CONCLUSION: Results revealed that STF is a non-physiological, static procedure leading to load increase on GH and AC joint cartilages, which may be a cause of potential joint osteoarthritis. Copyright © 2015 John Wiley & Sons, Ltd.

Using a Combination of Intralaminar and Pedicular Screw Constructs for Enhancement of Spinal Stability and Maintenance of Correction in Patients With Sagittal Imbalance: Clinical Applications and Finite Element Analysis.

STUDY DESIGN: Case series and finite element analysis. OBJECTIVE: To report the clinical results of using intralaminar screw-rod (ILS) constructs as supplements to regular pedicle screw (PS) constructs in "high risk for implant failure" patients and to report the results of a finite element analysis (FEA) of this new instrumentation technique. SUMMARY OF BACKGROUND DATA: Despite advances in surgery and implantation techniques, osteoporosis, obesity, revision surgeries, and neuromuscular conditions (such as the Parkinson disease) are challenges against achieving solid arthrodesis and maintaining correction. Additional fixation strategies must be considered in these patients. There is only one study in the literature suggesting that ILS can be used as alternative anchor points and/or to increase fixation strength in conjunction with the PSs. MATERIALS AND METHODS: Five patients (3 male and 2 female) with mechanical comorbidities underwent PS+ILS to treat sagittal imbalance. In radiologic analysis, thoracic kyphosis, lumbar lordosis, and sagittal vertical axis were analyzed. FEA of ILS augmentation technique were carried out.Four different models were created: (1) the full-construct model with ILS+PS 2 levels above and below the osteotomy of T10; (2) only PS 2 levels above and below T10; (3) ILS+PS 1 level above and below the osteotomy; and (4) short-segment PS with only PSs 1 level above and below the osteotomy. The stress/load distributions on the implants in vertebrae were analyzed. RESULTS: The mean age of the patients included in this study was 41 years and the mean follow-up was 28.2 months. A total of 87 PSs and 39 ILSs were used. Both sagittal vertical axis and kyphosis angles showed significant improvements maintained at the latest follow-up. No pseudarthrosis or instrumentation failures were observed. FEA indicated that addition of ILS construct to a PS construct enabled decreased load bearing and increased implant life. CONCLUSIONS: Addition of an ILS construct to PS construct decreases osteotomy line deformation and reduces stress on pedicle fixation points, and the combination improves fixation stability over the conventional PS-rod technique.

Treatment of Femur Fractures in Preschool Children with Double Pin Technique: Immediate Incorporated Hip Spica Casting by Two K-Wires.

The immediate hip spica casting is a popular treatment method for femoral fractures in the pediatric age group. Femoral shortening is the unacceptable result for the treatment. In this technique, we tried to describe the immediate spica casting technique pinning with double K-wire in preschool children and evaluate the results with this method. Sixteen patients (ten boys and six girls) are treated with this technique. Patients were treated under general anesthesia in the operating room. K-wire was introduced in the supracondylar area of the femur passing from the lateral to the medial side through both cortexes, and removed from the skin in the medial section. A second K-wire was introduced through the lateral side of the proximal fragment. While an assistant was applying traction to the pin to maintain the reduction, the lower extremity was put in a spica cast on the fractured side, while the knee joint on the other side was excluded from the spica casting process. The angulation after hip spica cast applied was 9.1° (range 7°-12°) on the frontal plane and 8.9° (range 5°-17°) on the sagittal plane. After spica cast removal, it was 8.5° (range 5°-13°) on the frontal plane and 9° (range 5°-17°) on the sagittal plane. No significant difference was found. The final mean leg length discrepancy was 4.8 mm (range 0-10 mm) at the time of cast removal. This technique may be effective for femoral diaphyseal fractures in preschool children to combine the spirits of external fixation with hip spica casting in one construct in order to correct angular deformities and length discrepancies.