Transverse Osteotomy Research Articles

Some Aspects of Total Hip Replacement with Subtrochanteric Shortening Osteotomy in Patients with Congenital Hip Dislocation (Review)

Total hip replacement (THR) in patients with a high congenital dislocation of the hip (Crowe type IV dysplasia in Crowe classification) is a technically difficult operation, associated with a high risk of complications. The most common variations of THRs used to restore the true center of rotation of the hip are subtrochanteric shortening osteotomy and proximal shortening osteotomy using the Paavilainen technique. Numerous publications refer to the technique and outcomes of subtrochanteric osteotomy, but fundamental differences of opinion persist on a number of points relating to the topic.The objective of the study is to analyze the publications on the treatment for crowe type IV hip dislocations using total replacement of the hip joint (HJ) with subtrochanteric shortening osteotomy.The hypothesis of the study was as follows: the method of fixation of the femoral component, the type of osteotomy and the design features of the implant (philosophy) are the factors that determine the effectiveness of the operation. The electronic databases eLIBRARY and PubMed were searched for publications containing keywords in Russian or English: high dislocation of the hip, total replacement of the Hj, shortening subtrochanteric osteotomy. As a result of the study, the proposed hypothesis was partially confirmed. There were only minor differences in the overall incidence of complications and the survivorship of implants when using different types of cementless stems. The incidence of non-unions after the installation of cemented femoral components was higher than with the implantation of cementless. We did not find convincing evidence of the advantage of the step-cut, V-shaped and oblique osteotomies compared with the transverse osteotomy. Typical complications for such operations were the nerve injuries, intraoperative hip fractures, dislocations and non-unions of the femur at the osteotomy site.

Biomechanical comparison between solid and cannulated intramedullary devices for midshaft clavicle fixation

BackgroundA method of closed reduction and internal fixation with cannulated screws was proposed as a surgical treatment of midshaft clavicle fractures. However, there are no mechanical studies about the cannulated screw used in the fixation of midshaft clavicle fracture. We conducted this study to compare the construct bending stiffness of a fixation midshaft clavicle fracture with a Knowles pin, cannulated screw and reconstruction plate. In addition, purchase lengths of both intramedullary devices were measured.MethodsAfter transverse osteotomy over the midpoint for fracture simulation, eighteen synthetic clavicles were assigned to 3 groups and fixed with reconstruction plate, Knowles pin or cannulated screw. Purchase length was defined as the engaged length of the intramedullary portion of the two intramedullary devices Stiffness, yield load and maximum load of the cantilever bending test were calculated of each tested synthetic bones.ResultsThe Knowles pin group had a significantly longer average intramedullary purchase length compared with that of the cannulated screw group. The construct stiffness in the reconstruction plate group (5.6 ± 0.9 N/mm) was higher than that of the intramedullary devices; the Knowles pin group (3.1 ± 0.6 N/mm) provided a greater construct stiffness than did the cannulated screw group (1.7 ± 0.4 N/mm) (p = 0.007). The cannulated screw group had the lowest yield and maximum load compared with the reconstruction plate and Knowles pin groups. Both the reconstruction plate and Knowles pin failed at the implant-bone interface. However, the cannulated screw group failed at the osteotomy site with broken implants.ConclusionThis study suggests that fixation of midshaft clavicle fractures with cannulated screws may lead to early failure due to inadequate mechanical strength. Ideal intramedullary clavicle devices should supply adequate intramedullary purchase lengths and mechanical strength.

Bone Formation and Adaptive Morphology of the Anterior Tibial Muscle in 3-mm Daily Lengthening Using High-Fractional Automated Distraction and Osteosynthesis with the Ilizarov Apparatus Combined with Intramedullary Hydroxyapatite-Coated Wire.

Purpose We studied osteogenesis and morphofunctional features of the anterior tibial muscle using 3-mm high-frequency automated lengthening with the Ilizarov apparatus alone and in combination with intramedullary nailing. Material and Methods Tibia was lengthened with a round-the-clock automated distractor at a 3-mm daily rate for 10 days in 16 mongrel dogs. In group 1 (n = 8), a 1.8-mm intramedullary titanium wire coated with hydroxyapatite was introduced into the tibial canal followed by Ilizarov frame mounting and transverse osteotomy of the diaphysis. Distraction mode was 0.025 mm x 120 increments a day. In group 2 (n = 8), distraction mode was the same but nailing was not used. Bone formation and the anterior tibial muscle were studied at two time points: (1) upon distraction completion; (2) three months after the apparatus removal. Bone formation was studied radiographically. Muscle preparations were examined histologically and stereomicroscopically. Results There was a threefold reduction in the distraction time in both groups. Consolidation took 13.83±4.02 days in group 1 and 33.7±2.4 days in group 2. Muscle macropreparations of the experimental limb in group 1 at study time points did not show significant differences from intact tissues. Muscle histostructure in both groups was characterized by activation of angiogenesis and myohistogenesis, but the volumetric density of microvessels in the lengthening phase was three times higher in group 1. Conclusion Combined technology significantly reduces the total lengthening procedure and does not compromise limb functions. Intramedullary HA-coated wires promote faster bone formation. The muscle was able to exhibit structural adaptation and plasticity of a restitution type.

Nonunion and Reoperation After Ulna Shortening Osteotomy.

Background: The primary purpose of our study was to identify factors associated with reoperation after ulna shortening osteotomy. Our secondary aims were to determine the rate and type of reoperation procedures. Methods: In this retrospective study, we included patients older than 18 years of age who underwent an ulna shortening osteotomy between January 2003 and December 2015. Medical records of patients were assessed for our explanatory variables, reoperations, and reporting of symptoms. We used bivariate and multivariable analyses to identify factors associated with reoperation after ulna shortening osteotomy. Results: Among 94 patients who underwent 98 ulna shortening osteotomies, there were 34 reoperations (35%). Nineteen patients (19%) underwent removal of hardware, 6 (6.1%) had a nonunion, and 9 (9.2%) underwent additional surgeries. Surgery on their dominant limb, trauma, and prior surgery to the ipsilateral wrist were associated with reoperation. In multivariable analysis, factors independently associated with reoperation were the dominant side being affected (odds ratio = 3.9; 95% confidence interval [CI] = 1.36-11) and traumatic origin (odds ratio = 3.4; 95% CI = 1.1-11). Bivariate analysis identified younger age and prior surgery of the affected wrist as factors associated with hardware removal. More operations for refixation due to nonunion of osteotomy were performed in patients with a transverse osteotomy compared with patients with an oblique osteotomy. Conclusions: One in 3 patients will undergo a reoperation after ulna shortening osteotomy, most often due to hardware irritation or nonunion of osteotomy. Awareness of these rates and predictive factors may be helpful for preoperative discussions and surgical decision making.

A Reliable Femoral Osteotomy in Total Hip Arthroplasty for Hartofilakidis Type C Developmental Dysplasia of the Hip: Proximal Femoral Reconstruction

BackgroundProcedure of the femur is extremely challenging during total hip arthroplasty (THA) for Hartofilakidis type C developmental dysplasia of the hip. The main purpose of this study is to compare the clinical effectiveness of proximal femoral reconstruction (PFR) with subtrochanteric transverse osteotomy (STO). MethodsBetween 2006 and 2015, 33 primary THAs in 26 patients were performed with PFR and 16 hips in 13 patients underwent STO. The mean follow-up was 4.2 (range, 2.2-10.8) years in PFR group and 5.9 (range, 3.5-11.3) years in STO group. At the final follow-up, clinical scores and radiographic results were evaluated for 33 hips in PFR group and 15 hips in STO group. ResultsPostoperative Harris hip scores and implant position did not differ between the treatment groups. The mean length of the oblique osteotomy line at proximal femur was 6.9 cm (range, 5.8-7.6 cm) in PFR group. The amount of bone union occurred within 6 months after surgery was 24 (72.7%) hips in PFR group and 9 (60.0%) in STO group. Three major postoperative complications occurred in PFR group, and medial femoral calcar erosion was noted in 1 hip in STO group. ConclusionSimilar with STO, the clinical results of PFR technique are a reliable solution for femoral procedure during THA in patients with Hartofilakidis type C developmental dysplasia of the hip.

Histomorphometric Analysis of Callus Formation Stimulated by Axial Dynamisation in a Standardised Ovine Osteotomy Model.

The cyclic axial dynamisation of a stabilised fracture is intended to promote callus formation and bone healing. Most studies focused on biomechanical properties or the quantity of new bone formation. Far less is known about the quality of newly formed callus tissues, such as tissue distribution and arrangement within the callus. The aim of this current study was to investigate the effect of cyclic, axial dynamisation on the quantity and quality of callus in an established delayed fracture healing model. In 41 sheep transverse osteotomies with a gap size of 3 mm were stabilised with a unilateral external fixator. In 32 of these, fracture ends were axially stimulated with displacement amplitudes of 0.8 mm, 0.4 mm, 0.2 mm, or 0.0 mm, respectively, for six weeks. In the remaining 9 sheep of the control group, an additional external fixator was mounted to achieve almost total rigidity. Animal material originating from a past animal experiment was reanalysed in this study. Histological thin-ground sections were histomorphometrically analysed regarding the histological structure and composition of the defect region. A slight tendency towards an increase in size of total callus area, area of new bone (nB.Ar), and cartilage (Cg.Ar) was detected with increasing displacement amplitudes compared to the control group. At the anterior callus side nB.Ar and Cg.Ar were significantly larger than at the posterior side in all groups independent of treatment. Regarding the quality of callus, areas of very compact bone were predominant in the treatment groups whereas in the control group a slight shift to more porous bone was observed. No difference of callus compactness was observed between the anterior and the posterior side. The established method to assess the local compactness of callus areas is a useful tool to quantitatively determine the spatial distribution of new bone tissue within the callus. The application of this method in combination with biomechanical testing might reveal interesting relations between tissue distribution and bone strength that, with traditional histomorphometry, cannot be identified.

Correction of Biapical Tibial Deformity by True Spherical Osteotomy, Modified Circular External Skeletal Fixation and Distraction Osteogenesis

Objectives The aim of this study was to describe a case of biapical tibial deformity as a result of premature distal physeal closure corrected by true spherical osteotomy, circular external skeletal fixation and distraction osteogenesis. Methods A 6-month-old male Labrador Retriever was presented for the evaluation and treatment of angular limb deformity of the left pelvic limb, with radiography and computed tomography revealing a multiplanar, biapical, compensatory tibial growth deformity, with marked distal tibial recurvatum and varus. A true spherical osteotomy was performed at the distal tibial centre of rotation of angulation (CORA), allowing for correction of the deformity in three planes, with a transverse osteotomy performed at the most proximal CORA. A circular external skeletal fixator was applied and distraction osteogenesis performed at the transverse osteotomy. Latency, distraction osteogenesis, and consolidation were performed over a 113-day period. Results At frame removal, tibial length discrepancy improved from 16.8% to 0.6% and frontal plane varus angulation improvement from 20° to 5°, when compared with the contralateral limb. Long-term evaluation revealed a satisfactory clinical and cosmetic outcome, judged by the clinician and owners, with force plate analysed symmetry index of the pelvic limb within reported normal limits. Clinical significance To our knowledge this is the first case report illustrating the value of true spherical osteotomy for the treatment of an angular limb deformity when performed in combination with distraction osteogenesis in a canine pelvic limb.

In vitro biomechanical comparison of headless compression versus cortex screws for fixation of simulated midbody proximal sesamoid bone fractures in horses

A midbody fracture of a proximal sesamoid bone (PSB) is a severe injury, especially in racehorses. Screw fixation may be the only option for horses to return to athletic activity. In a cadaveric biomechanical study, fixation of simulated transverse midbody PSB fractures with a 4.5 mm headless compression screw (HCS) was compared to the fixation using a 4.5 mm cortex screw (CS) inserted in lag fashion. The front limbs of 8 horses were prepared with a standardized midbody transverse osteotomy in each medial PSB. The left or the right limb of each pair was randomly assigned to the CS or HCS group. Fracture reduction and fixation was controlled by radiography. Markers were fixed proximal and distal to the osteotomy to document gap opening by an image correlation measurement. Cyclic compressive loading was applied with a hydraulic cylinder in an axial manner leading to tensile cyclic loading in the PSBs. After mechanical testing all limbs were radiographed to document the mode of failure. The mean cycles to total failure were 27,803 for the HCS group and 36,624 for the CS group, respectively. A mean of 14,444 cycles (HCS group) versus 27,464 cycles (CS group) was recorded at a fracture gap opening of 10 %. The mean value of initial stiffness was 300 N/mm (HCS group) versus 590 N/mm (CS group). On post-testing radiographs, failure by screw breakage was detected in 3/8 limbs of the HCS group and in 2/8 limbs of the CS group. Screw pullout and bone failure was noted in 5 limbs in each group. In one limb of the CS group, the medial suspensory branch was disrupted and the fracture fixation was intact. None of the differences between HCS and CS constructs reached statistical significance. However, the lower absolute numbers of cycles sustained before failure, at 10 % gap opening and lower initial stiffness of HCS constructs as well as limitations of the study warrant further investigation before clinical use of the HCS for this indication can be recommended.

Minimally invasive double-level osteotomy of the first metatarsus for treatment of severe hallux valgus

Background Surgery for the treatment of severe hallux valgus (HV) is commenced to correct the forefoot deformity, provide metatarsalgia relief, and provide a stable biomechanically functional foot. Many surgeons advocate moving from open surgery to minimally invasive techniques, replacing large incisions with smaller ones through which the surgeon can work. Minimally invasive techniques have been successfully used for mild to moderate HV deformities; however, controversy exists for their use in cases with more severe involvement. The aim of this prospective study was to assess the clinical and radiological outcomes of a minimally invasive technique for management of severe HV deformity. Patients and methods Between March 2015 and August 2017, a total of 24 feet in 18 active patients, comprising 11 female and seven male patients, with six patients having bilateral involvement, met our selection criteria for symptomatic severe HV deformity and were treated with a minimally invasive double-level metatarsal osteotomy technique. The surgery is done through simple transverse osteotomy, with lateral translation, of the first metatarsus both proximally and distally combined with selective distal soft-tissue dissection. The average age of patients was 37.7 years. Clinically, the American Orthopedic Foot and Ankle Society score and the subjective patient's satisfaction were evaluated. Radiologically, HV angle, distal metatarsal articular angle, and intermetatarsal angle and joint congruity were measured preoperatively, postoperatively, and at the end of the follow-up period. All data were statistically analyzed. Results The mean follow-up period was 22.7 months (range, 18–30 months). Union was achieved in all osteotomies in a mean of 6.67±0.45 weeks. Each radiological and clinical parameter showed a statistically significant improvement (P<0.001), with negligible first-ray shortening (P=0.547) and a few complications. At the end of follow-up period, no patient was dissatisfied. Conclusion Minimally invasive double-level first metatarsal osteotomy technique with selective distal soft-tissue dissection provides a simple, effective procedure, and reproducible alternative for treatment of severe HV deformity.

Fibular osteotomy strategies and techniques: A survey of the limb lengthening and reconstruction society membership

Context: Fibular osteotomy is a necessary element of most tibial procedures, but there is no consensus on the ideal location, orientation, or technique for the procedure. Aims: We surveyed limb reconstruction surgeons to learn how often a fibular osteotomy was performed, details of surgical technique, and varying intraoperative parameters. Settings and Design: A cross-sectional survey was sent to all members of the Limb Lengthening and Reconstruction Society – North America, as well as experienced international limb reconstruction surgeons. Subjects and Methods: The survey contained 12 questions regarding fibular osteotomies in the setting of limb reconstruction surgery. Responses were not specific to any particular procedure. Data were collected on how often a fibular osteotomy was performed, details of surgical technique, and varying intraoperative parameters. Statistical Analysis Used: Statistical tests employed include Kruskal–Wallis, Mann–Whitney U, Chi-square, and Fisher's exact tests where appropriate. Results: A total of 149 surveys were returned. Most surgeons perform fibular osteotomy at the junction of middle and distal thirds or in middle third, 36.9% and 31.5%, respectively. The least common location for osteotomy was in the proximal third of fibula (4%). The most common method for creating fibular osteotomy was with an oscillating saw (48.3%), followed by drilling holes and using an osteotome (45.0%). The average reported time for the completion of osteotomy was 13 ± 7.2 min, with shortest average time reported for surgeons who perform osteotomy in the distal third (11.3 ± 6.4 min) and longest for those at proximal third (14.6 ± 10.3 min). The most common closure technique was that of layered closure (97%). Conclusions: Most surgeons perform a transverse osteotomy occurring at the junction of the middle and distal thirds of the fibula. The osteotomy is most commonly performed at the beginning of the case using either an oscillating saw or multiple drill holes and osteotome. Continued research is needed to determine the specific indications for performing a fibular osteotomy, if the anatomic location of the fibula osteotomy is important, and when a segment of the fibula should be removed.

Radiographic cortical thickness parameters as predictors of rotational alignment in proximal femur fractures: A cadaveric study.

Radiographic assessment tools such as the cortical step sign (CSS) or the diameter difference sign (DDS) aim to identify clinically relevant rotational malalignment after long bone fracture fixation. We aimed to analyze the effect of rotational malalignment on CSS and DDS parameters in a subtrochanteric fracture model and to construct a prognostic model to identify clinically relevant rotational malalignment. A subtrochanteric transverse osteotomy was set in human femora. Rotation was set stepwise from 0° to 30° in internal and external rotation. Images were obtained using a C-arm and transferred for measuring the medial cortical thickness (MCT), lateral cortical thickness (LCT), femoral diameter (FD) in AP and the anterior cortical thickness (ACT) as well as the posterior cortical thickness (PCT) and the FD of the proximal and the distal main fragment. There were significant differences between the various levels of rotation for each of the absolute values of the evaluated variables. MCT, PCT and FD (AP & lat.) were the most affected parameters. In internal rotation, the MCT, PCT and the FD were the most affected variables. The parameters with the highest correlation with femoral rotation were ACT, PCT and FD. A model combining ACT, LCT, PCT and FD AP was most suitable model in identifying rotational malalignment. The best prediction of clinically relevant rotational malalignment was obtained with the FD and the PCT. The CSS and the DDS are promising tools for detecting rotational deformities of the proximal femur and should be used intra- and postoperatively. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Корекційна остеотомія бічної кісточки гомілки при її хибно консолідованих переломах

Мета. Проаналізувати результати застосування модифікованої методики корекційної остеотомії бічної кісточки гомілки при її хибно консолідованих переломах без виражених деструктивно-дистрофічних змін травмованого гомілковостопного суглоба.
 Матеріали і методи. Дослідження проведено щодо 37 пацієнтів, з них чоловіків - 16, жінок - 21, середній вік яких становив (38 ± 7) років. З моменту травми минуло від 6 до 15 міс, у середньому - (7,8 ± 1,9) міс. Під час рентгенологічного обстеження у пацієнтів виявлено післятравматичний остеоартроз гомілковостопного суглоба І-ІІ стадії за Келгреном - Лоуренсом.
 Корекційна остеотомія включала поперечну остеотомію бічної кісточки гомілки на рівні суглобової щілини гомілковостопного суглоба, що уможливило виконати трьохплощинну корекцію положення кісточки та відновити співвідношення в гомілковостопному суглобі.
 Функціональні результати оцінювали за шкалою AOFAS (American Orthopaedic Foot and Ankle Society Score) для гомілковостопного суглоба та заднього відділу стопи до та після хірургічного лікування. Ступінь прогресування остеоартрозу визначали за результатами рентгенографії в навантаженні згідно з класифікацією Келгрена - Лоуренса. Середній термін спостереження з аналізом результатів становив (1,9 ± 0,6) року.
 Результати. Оцінка функціональних результатів за шкалою AOFAS у межах терміну спостереження зросла з (58,7 ± 2,4) до (86,2 ± 1,8) бала. Під час рентгенологічного обстеження у всіх пацієнтів спостерігали відновлення осі гомілковостопного суглоба, але у 8 (21%) пацієнтів виявили ІІІ стадію остеоартрозу, що свідчило про його прогресування.
 Висновки. Модифікована методика корекційної остеотомії бічної кісточки гомілки при її хибно консолідованих переломах дає змогу відновити конгруентність та біомеханічну вісь подкодженого суглоба, значно покращити його функціональну здатність та уповільнити прогресування післятравматичного остеоартрозу.

Nonunion Rates Among Ulnar-Shortening Osteotomy for Ulnar Impaction Syndrome: A Systematic Review

The purpose of this study was to systematically review all available literature reporting nonunion rates of ulnar-shortening osteotomies (USO) used for the treatment of ulnar impaction syndrome (UIS) and to compare those rates among transverse versus oblique cuts for the osteotomy. Electronic databases including PubMed, EMBASE, and Cochrane Central Register of Controlled Trials were searched for studies that evaluated outcomes of both transverse and oblique USO for UIS. Level of evidence was determined by 2 independent reviewers. Studies were screened based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and inclusion and exclusion criteria were applied. A total of 37 studies (1,423 patients) were included in final analysis. The average rate of nonunion and delayed union for each group (transverse and oblique osteotomy) was calculated. The average rate of nonunion among all osteotomies was 4.0%. The average rate of nonunion was 4.16% and 3.86% in transverse osteotomies and oblique osteotomies, respectively. This difference was not statistically significant. The average rate of delayed union, in those studies that reported delayed union, was 5.7%. The average rate of delayed union was 7.41% and 4.1% in transverse osteotomies and oblique osteotomies, respectively. Based on our review of the literature, there is no difference in the rate of nonunion between transverse and oblique osteotomies. Therefore, the decision of which of the 2 surgical techniques should not be based on rate of nonunion. Therapeutic IV.

Total hip arthroplasty with a monoblock conical stem and subtrochanteric transverse shortening osteotomy in Crowe type IV dysplastic hips.

This series assessed the clinical and radiographic outcomes of total hip arthroplasty (THA) with femoral shortening osteotomy for the management of patients with Crowe type IV hip dysplasia. Only patients with Crowe type IV hip dysplasia who underwent primary THA combined with a subtrochanteric transverse osteotomy with an uncemented monoblock conical stem were included. The clinical and radiographic evaluations were performed before and immediately after surgery, and at last follow-up. The hip function was assessed with the Harris Hip Score (HHS). Seventy-four patients (102 hips) with a mean age of 53.9 (range, 20-83) were evaluated at an average follow-up of 11.3years (range, 5-25). Stem revision occurred in two (1.9%) cases, with a survivorship of 95.9% (95%IC, 91.9-99.9%) at tenyears. The average HHS increased from 44 (range, 15-78) pre-operatively to 90.3 (range, 62-100) at last follow-up (p < 0.001). Osteotomy site non-union and early dislocation were observed in 3.9 and 3.8%, respectively. No cases of nerve palsy were reported. THA with a monoblock conical stem associated with subtrochanteric transverse osteotomy provides good long-term survival, clinical and radiographic results. It may be considered an effective management of patients with Crowe IV hip dysplasia.

Results of Crowe Type IV Developmental Dysplasia of Hip Treated by Subtrochantric Osteotomy and Total Hip Arthroplasty

Background:Crowe type IV developmental dysplasia of hip (DDH), subtrochanteric shortening osteotomy is required to restore the hip joint. Several approaches have been described for subtrochanteric shortening osteotomy. Several osteotomy fixation techniques have been defined for Crowe type IV DDH. This study evaluates the outcomes of subtrochanteric shortening osteotomy fixed with a combination of split onlay autograft and distal fluted femoral stem.Materials and Methods:A retrospective study was carried out on 41 hips of 37 patients treated with total hip replacement for Crowe type IV developmental dysplasia of the hip by subtrochanteric transverse osteotomy and fixed with split intercalary autograft by two cables. A femoral stem with proximal coated and distally fluted was used. The patients were evaluated at a mean of 34 months (range 12–68 months) for union time, leg equalization, and clinical outcomes. Results:Mean time of union was 13.5 ± 4.6 weeks (range 6–24 weeks). Intraoperative instability of the osteotomy site (n = 16) that was encountered at the trial stage was restored properly by this surgical protocol. Leg length discrepancies were improved to 1.4 ± 0.8 cm (range 0–3 cm). Harris scores were improved from 47.7 ± 10.8 (range 30–68) to 88 ± 5.6 (range 72–98) (P < 0.05) points. There was no nonunion.Conclusions:Distally well-fitted stem and strengthening of fixation with split intercalary autograft promote additional rotational stability and improve bone union.

Biomechanical Analysis of a Novel Buried Fixation Technique Using Headless Compression Screws for the Treatment of Patella Fractures.

The traditional technique for patella fracture fixation utilizes prominent hardware. Prominent hardware use, however, results in a high rate of reoperation for symptomatic implant removal. This biomechanical study evaluates the effectiveness of a novel patella fixation technique that minimizes implant prominence. Patellar transverse osteotomies were created in 13 pairs of cadaveric knees. Paired knees were assigned to either standard fixation (SF) using cannulated partially threaded screws and stainless steel wire tension band, or buried fixation (BF) using headless compression screws with a No. 2 FiberWire tension band and a No. 5 FiberWire cerclage suture. Quadriceps tendons were cyclically loaded to full extension followed by load to failure. The gap across the fracture site, stiffness, and load to failure were measured. The differences in stiffness and load to failure between the 2 groups were not statistically significant. During cyclic loading, significantly greater gapping was observed across the fracture site in the BF group compared with SF group (P < .05). Both constructs failed under loads that exceeded typical loads experienced during the postoperative rehabilitation period. Nevertheless, the BF technique demonstrated larger gap formation and a reduced load to failure than the SF technique. Further clinical studies are therefore underway to determine whether the use of constructs with decreased stability but increased patient comfort could improve clinical outcomes and reduce reoperation rates.

Combination therapy with BMP-2 and psoralen enhances fracture healing in ovariectomized mice.

The advantages of combining local delivery of bone morphogenetic protein (BMP)-2 with systemic or local anti-osteoporosis treatments have also been studied for enhancing osteoporotic fracture healing. The aim of the present study was to evaluate the effect of combination therapy with BMP-2 and psoralen on fracture repair in ovariectomized mice. At 6 weeks after bilateral ovariectomy, mice (n=30) underwent unilateral transverse osteotomy on the femur and were divided into 3 groups. In the model group (n=10), animals were implanted with an absorbable collagen sponge (ACS) alone and administered physiological saline intragastrically (i.g.). In the recombinant human (rh)BMP-2 group (n=10), animals were implanted with an ACS loaded with 2.5 µg rhBMP-2 and administered physiological saline i.g. In the psoralen + rhBMP-2 group (n=10) animals were implanted with an ACS loaded with 2.5 µg rhBMP-2 and administered psoralen i.g. The mice were euthanized after 21 days and their fractured femurs were assessed by micro computed tomography, histological analysis and biomechanical testing. Furthermore, the serum of the animals was analyzed. Psoralen + rhBMP-2 exerted more beneficial effects on callus consolidation and biomechanical strength. In addition, increased bone-specific alkaline phosphatase levels and decreased C-terminal telopeptide of type-1 collagen were observed in the Psoralen + rhBMP-2 group. However, no difference in estrogen levels was detected between the groups. In conclusion, the present study demonstrated that in ovariectomized mice, combination of locally delivered BMP-2 and systemically administered psoralen improved bone healing compared with BMP-2 alone.

A Locked Intraosseous Nail for Transverse Patellar Fractures: A Biomechanical Comparison with Tension Band Wiring Through Cannulated Screws.

Displaced transverse patellar fractures require open reduction and internal fixation. State-of-the-art stabilization techniques are tension band wiring (TBW) using Kirschner wires or cannulated screws. These techniques are associated with high rates of secondary fracture displacement, implant migration, implant prominence, wound-healing disturbances, and the need for implant removal. Recently, a locked intraosseous patellar nail prototype was developed. The aim of the present study was to investigate the biomechanical performance of this nail compared with TBW using cannulated screws. Seven paired fresh-frozen human cadaveric knees were stripped of all soft tissues except the extensor apparatus. A transverse osteotomy was created to simulate an OTA/AO type 34-C1 transverse patellar fracture. The specimen pairs were randomly assigned to be fixed with TBW using cannulated screws or with the new intraosseous nail. Each specimen was cyclically tested for 5,000 cycles by pulling on the quadriceps tendon and simulating active knee extension and passive knee flexion within the range from 90° of flexion to full knee extension. Anterior and articular margin displacement of the fracture as well as interfragmentary rotation around the mediolateral axis were investigated with optical motion tracking after 100, 500, 1,000, 2,500, and 5,000 test cycles. Within the respective 5 testing-cycle time points evaluated, the articular margin displaced on average 68%, 60%, 72%, 76%, and 81% less after intraosseous nailing compared with TBW. Whereas the difference remained nonsignificant after 100 and 500 cycles (p ≥ 0.116), a trend toward significance was observed after 1,000 cycles (p = 0.063), which became significant after 2,500 and 5,000 cycles (p ≤ 0.043). From a biomechanical point of view, the locked intraosseous patellar nail may be an alternative to TBW using cannulated screws because of the higher interfragmentary stability provided at the articular fracture site. A locked patellar nail for transverse patellar fractures achieved a stable osteosynthetic construct that may reduce hardware-associated complications because of its intraosseous positioning.

Biomechanical comparison of cemented versus non-cemented anterior screw fixation in type II odontoid fractures in the elderly: a cadaveric study

Background ContextOdontoid process fractures are the most common injuries of the cervical spine in the elderly. Anterior screw stabilization of type II odontoid process fractures improves survival and function in these patients but may be complicated by failure of fixation. PurposeThe present study aimed to determine whether cement augmentation of a standard anterior screw provides biomechanically superior fixation of type II odontoid fractures in comparison with a non-cemented standard screw. Study DesignTwenty human cadaveric C2 vertebrae from elderly donors (mean age 83 years) were obtained. MethodsAnderson and D'Alonzo type IIa odontoid fracture was created by transverse osteotomy, and fluoroscopy-guided anterior screw fixation was performed. The specimens were divided into two matched groups. The cemented group (n=10) had radiopaque high viscosity polymethylmethacrylate cement injected via Jamshidi needle into the base of the odontoid process. The other group was not augmented. A V-shaped punch was used for loading the odontoid in an anteroposterior direction until failure. The failure state was defined as screw cutout or 5% force decrease. Mean failure load and bending stiffness were calculated. ResultsThe mean failure load for the cemented group was 352±12 N compared with 168±23 N for the non-cemented group (p<.001). The mean initial stiffness of the non-cemented group was 153±19 N/mm compared with 195±29 N/mm for the cemented group (p<.001) ConclusionsCement augmentation of an anterior standard screw fixation of type II odontoid process fractures in elderly patients significantly increased load to failure under anteroposterior load in comparison with non-augmented fixation. This may be a valuable technique to reduce failure of fixation.

Combined Nasal Osteotomies With Caudal Transverse Osteotomy and Their Effect on Dorsal Geometry

Congenital, traumatic, or developmental bony vault deformities may require additional interventions rather than classical osteotomies to correct the surface structure or angulations of the nasal bones in rhinoplasty. The aim of the study was to determine the effects of the additional osteotomies applied for the correction of the nasal vault asymmetries retrospectively. Twenty-one patients among 512 primary rhinoplasty cases between 2011 and 2016 with bony vault asymmetries were included in the study. Three patients had bilateral convex, 6 patients had unilateral convex, and 7 patients had unilateral concave surface deformities. Five patients had concave deformity on one side and convex deformity on the other side. Double-layer lateral osteotomies and caudal transverse osteotomies were conducted for the correction of the severe surface anatomy deformities of the nasal bones. The caudal transverse osteotomy was delicately performed with a special osteotome, which was designed to protect inner periosteum and mucosa of the nasal bone, and to prevent uncontrolled fracture formation with thinned edge. Twenty patients (95.2%) had favorable results with restoration of a symmetric bony and cartilaginous nasal vault configuration. None of the bone fragments showed any rotation or malposition. One (4.8%) patient with a crooked nose had suboptimal dorsal geometry without requiring revisional surgery at the level of the cartilaginous nasal vault. The author described the morphology, clinical relevance, and correction methods of the nasal vault and the changes that occur in this area during rhinoplasty in patients with concave, convex, or combined three-dimensional nasal bone deformities. Level of Evidence: 4.