RESUMEN
RATIONALE: Kirner's deformity is an uncommon deformity of finger, characterized by palmo-radial curvature of distal phalanx of the fifth finger. The specific mechanism remains unknown yet. This study aims to present a case report to add the knowledge on this type of deformity. PATIENT CONCERNS: A 9-year-old girl presenting with deformity of her fifth finger since she was born was admitted to our hand surgery clinic. MRI findings showed widened epiphyseal plate, L-shaped physis, but normal flexor digitorum profundus tendon insertion, without any significantly enhanced soft issues. DIAGNOSIS: Kirner's deformity of the fifth finger. INTERVENTIONS: We presented 2 surgical choices for the patient: one was wedge osteotomy of the distal phalanx to correct the mechanical line of the distal phalanx and fixation with Kirschner wire and the other one was cut-off of deep flexor tendon insertion with brace immobilization, but her guardians refused either of them. OUTCOMES: Consecutive follow-up was performed for 19 months after the first visit, showing no any change in finger shape and function. LESSONS: The L-shaped epiphyses may be the cause of Kirner's deformity and further attention should be paid on in the clinic. This case report provided a basis for the etiological diagnosis and future treatment of Kirner's deformity.
Asunto(s)
Falanges de los Dedos de la Mano/anomalías , Deformidades Congénitas de la Mano/diagnóstico por imagen , Osteotomía/instrumentación , Cuidados Posteriores , Hilos Ortopédicos/normas , Tirantes/normas , Niño , Femenino , Falanges de los Dedos de la Mano/cirugía , Placa de Crecimiento/anomalías , Placa de Crecimiento/diagnóstico por imagen , Deformidades Congénitas de la Mano/cirugía , Humanos , Imagen por Resonancia Magnética/métodos , Osteotomía/métodos , Tendones/diagnóstico por imagen , Tendones/cirugía , Negativa del Paciente al TratamientoRESUMEN
OBJECTIVE: To evaluate the effectiveness of nitinol memory alloy two foot fixator combined with Kirschner wire in the treatment of trans-scaphoid perilunate dislocation. METHODS: Between September 2011 and October 2018, 17 patients with trans-scaphoid perilunate dislocation were treated with nitinol memory alloy two foot fixator and Kirschner wire. There were 12 males and 5 females, with an average age of 32.6 years (range, 23-52 years). The disease duration was 8 hours to 9 days, with an average of 6.5 days. The causes of injury included 6 cases of falling injury, 4 cases of traffic accident injury, 3 cases of stress injury of wrist caused by sports, 2 cases of violent injury of wrist caused by machine impact, 1 case of military training injury, and 1 case of other injury. One case was complicated with nerve injury. According to Herbert's classification, all the fractures were type B4. At 1 week before operation, 3 months, 6 months after operation and last follow-up, the wrist function was evaluated according to the Krimmer scale score. RESULTS: All the 17 patients were followed up 10.5-48 months, with an average of 18.6 months. There was no loosening or infection of the internal fixator, no necrosis of the scaphoid and lunate. The periosteal dislocations of the patients were well reduced and the scaphoid fractures all healed. The healing time was 4-18 months, with an average of 11.3 months. The Krimmer wrist scores were 37.5±4.4, 61.3±7.2, 83.3±9.3, 87.3±8.2 at 1 week before operation, 3 months, 6 months after operation and last follow-up, respectively. The Krimmer wrist score at each time point after operation was significantly improved when compared with that before operation ( P<0.05), and at 6 months after operation and last follow-up than at 3 months after operation ( P<0.05). There was no significant difference between at 6 months and last follow-up ( P>0.05). At last follow-up, the Krimmer wrist function was excellent in 13 cases, good in 2 cases, fair in 1 case, poor in 1 case, and the excellent and good rate was 88.23%. CONCLUSION: Nitinol memory alloy two foot fixator combined with Kirschner wire in the treatment of trans-scaphoid periosteal dislocation has definite effectiveness, simple operation, and good recovery of wrist function after operation.
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Aleaciones , Hilos Ortopédicos , Fijación Interna de Fracturas , Fracturas Óseas , Luxaciones Articulares , Hueso Escafoides , Adulto , Aleaciones/uso terapéutico , Hilos Ortopédicos/normas , Femenino , Fijación Interna de Fracturas/normas , Fracturas Óseas/cirugía , Humanos , Luxaciones Articulares/cirugía , Masculino , Persona de Mediana Edad , Hueso Escafoides/cirugía , Resultado del Tratamiento , Adulto JovenRESUMEN
RATIONALE: Tension band wiring is the most widely accepted technique for the treatment of patellar fractures but the technique is associated with common complications like wire migration, prominence, and breakage. To reduce these complications, we developed and propose a modified technique that has a superior biomechanical strength and a potential to reduce such postoperative complications. PATIENT CONCERNS: The patient presented with pain and mild swelling in his left knee after he slipped on the floor and fell on his left knee. He has no significant past medical or surgical history. The patient took the tension band wiring as the first choice because of the wide acceptance. But he worried about the complications. DIAGNOSES: X-ray showed a transverse fracture of the left patella with an inferior pole occult fracture. INTERVENTIONS: The patient was operated with a modified technique of the classic tension band wiring for patellar fractures. In our 4-step procedure, double tension cerclage wires were wrapped under the exposed ends of the Kirschner wires (K-wires) and the tendons in figure-of-8 fashion. The aim was to increase the biomechanical strength so that when one of the tension wires fail, the other one can hold the fragments together. OUTCOMES: The patient recovered very well and without any complications. The patient was followed-up for 1 year and the fracture has united very well, with satisfying knee range of motion. LESSONS: From this case study, we can detect the biomechanical advantages of our technique which can increase the stability of the fracture and that allows early functional exercise and additionally the micromotion at the fracture site has a beneficial effect of fracture union. Based on the perfect outcomes, our technique is worthy of clinical application.
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Hilos Ortopédicos/normas , Traumatismos de la Rodilla/cirugía , Rótula/cirugía , Complicaciones Posoperatorias/prevención & control , Hilos Ortopédicos/efectos adversos , Fijación Interna de Fracturas/métodos , Fracturas Óseas/cirugía , Humanos , Articulación de la Rodilla/patología , Masculino , Persona de Mediana Edad , Rótula/diagnóstico por imagen , Rótula/patología , Radiografía/métodos , Resultado del TratamientoRESUMEN
BACKGROUND: Patients with a simple transversal fracture of the olecranon are often treated with a tension band wiring (TBW), because it is known as a biomechanically appropriate and cost-effective procedure. Nevertheless, the technique is in detail more challenging than thought, resulting in a considerable high rate of implant-related complications like k-wire loosening and soft tissue irritation. In the literature, a distinction is generally only made between transcortical (bi-) and intramedullary (mono-) fixation of the wires. There is the additional possibility to fix the proximal bent end of k-wire in the cortex of the bone and thus create a tricortical fixation. The present study investigates the effectiveness of bi- and tricortical k-wire fixation in a biomechanical approach. METHODS: TBW of the olecranon was performed at 10 cadaver ulnas from six donors in a usual manner and divided into two groups: In group 1, the k-wire was inserted by bicortical fixation (BC), and in group 2, a tricortical fixation (TC) was chosen. Failure behavior and maximum pullout strength were assessed and evaluated by using a Zwick machine. The statistical evaluation was descriptive and with a paired t test for the evaluation of significances between the two techniques. RESULTS: The average age of the used donors was 81.5 ± 11.5 (62-92) years. Three donors were female, and three were male. Ten k-wires were examined in BC group and 10 in the TC group. The mean bone density of the used proximal ulnas was on average 579 ± 186 (336-899) HU. The maximum pullout strength was 263 ± 106 (125-429) N in the BC group and increased significantly in the TC group to 325 ± 102 (144-466) N [p = .005]. CONCLUSION: This study confirms for the first time biomechanical superiority of tricortical k-wire fixation in the olecranon when using a TBW and may justify the clinical use of this method.
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Hilos Ortopédicos/normas , Fijación Interna de Fracturas/instrumentación , Fracturas Óseas/cirugía , Olécranon/lesiones , Olécranon/cirugía , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
PURPOSE: This study aimed to compare the radiographic and functional results of Arbeitsgemeinschaftfür Osteosynthesefragen (AO) type C2/C3 fracture of distal radius between volar locking plate (VLP) and external fixation (EF). METHODS: It was a retrospective comparative study. Between January 2015 and March 2018, a total of 62/117 patients who underwent EF (23) or VLP fixation (39) for AO type C2/C3 distal radius fractures were assessed. The follow-up period was at least 12 months. Gartland-Werley scale and the disabilities of the arm, shoulder, and hand (DASH) scale were used to evaluate the overall functional outcomes; wrist range of motion and grip strength were measured. The radiographic parameters included radial inclination, volar tilt, radial length, ulnar variance, and articular step-off. All of the comparisons were performed using SPSS 21.0. RESULTS: The mean follow-up time was 17.1 months. At final visit, VLP performed better in wrist flexion (69.7° vs 62.3°, p < 0.001), forearm pronation (73.1° vs 64.8°, p = 0.027) and supination (70.6° vs 63.1°, p = 0.033) than EF, but not different with regard to other kinematic parameters. No significant difference was found between two groups, in term of Gartland-Werley or DASH score (p > 0.05). The ulnar variance and articular step-off was significantly more improved in VLP than EF group, being 0.6 vs 1.6 mm (p = 0.002) and 0.5 vs 1.2 mm (p = 0.007). The overall rate of complications did not differ in both groups (28.2% vs 34.5%) (p = 0.587). CONCLUSIONS: Compared to EF, VLP fixation showed better performance in wrist mobility, correction of ulnar variance, and improving articular congruence, but with the comparable overall functional outcomes and complication rate.
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Placas Óseas/normas , Hilos Ortopédicos/normas , Fijación de Fractura/instrumentación , Fracturas del Radio/diagnóstico por imagen , Fracturas del Radio/cirugía , Adulto , Anciano , Femenino , Fijación de Fractura/métodos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
CASE: A 30-year-old man was found to have a posteriorly displaced osteochondral shear fracture of his left humeral head, likely from dislocation and relocation. The fragment was fixed in its native position using headless screws, and the patient regained full strength and range of motion within 9 months. CONCLUSIONS: Osteochondral shear fractures of the humeral head appear to shear off the anteromedial articular joint surface after dislocation and relocation. One should be suspicious for associated labral tears. Arthroplasty is a valid treatment option, but select patients may be eligible for other viable options.
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Cabeza Humeral/patología , Luxación del Hombro/complicaciones , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Adulto , Artroplastia/instrumentación , Hilos Ortopédicos/normas , Humanos , Cabeza Humeral/diagnóstico por imagen , Masculino , Radiografía/métodos , Rango del Movimiento Articular/fisiología , Lesiones del Manguito de los Rotadores/etiología , Lesiones del Manguito de los Rotadores/cirugía , Fracturas del Hombro/etiología , Resultado del TratamientoAsunto(s)
Luxaciones Articulares/patología , Articulación del Dedo del Pie/lesiones , Articulación del Dedo del Pie/patología , Hilos Ortopédicos/normas , Preescolar , Diagnóstico Diferencial , Pie/diagnóstico por imagen , Traumatismos de los Pies/patología , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/cirugía , Masculino , Reducción Abierta/métodos , Radiografía , Articulación del Dedo del Pie/diagnóstico por imagen , Resultado del TratamientoRESUMEN
RATIONALE: Mallet finger fracture is a common sports-related injury that may lead to the tearing of extensor tendon and protrusion of a bony fragment located at the base of the distal phalanx. We affirmed that the elastic fixation of with two K-wires technique is a good method to deal with Mallet Finger fractures that fractures could gain effective fixation than the conventional treatment method and avoid surgical incision complication PATIENT CONCERNS:: We reported a 33-year-old female patient came to our hospital complaining of mild pain, swelling and her right little finger was deformed because of sport's injury. DIAGNOSIS: Acute mallet finger fracture type IV B according to Doyle classification of mallet injuries. INTERVENTIONS: We performed an emergency operation for the elastic fixation of the mallet finger fractures with two K-wires. OUTCOMES: After the surgery, the patient showed functional recovery. No evidence of recurrence was noted 6 months after the operation, and the patient showed no symptoms of sports-related injuries. LESSONS: We discuss the clinical diagnosis, treatment, and follow-up of the patient and suggest that elastic fixation with two K-wires is a good method to treat mallet finger fractures.
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Hilos Ortopédicos/normas , Traumatismos de los Dedos/cirugía , Falanges de los Dedos de la Mano/lesiones , Fracturas Óseas/cirugía , Adulto , Cuidados Posteriores , Hilos Ortopédicos/efectos adversos , Femenino , Traumatismos de los Dedos/diagnóstico por imagen , Falanges de los Dedos de la Mano/cirugía , Fijación Interna de Fracturas/métodos , Humanos , Rango del Movimiento Articular/fisiología , Recuperación de la Función/fisiología , Traumatismos de los Tendones/cirugía , Resultado del TratamientoRESUMEN
Congenital pseudarthrosis of the clavicle (CPC) is a very rare pathology of which over 200 cases have been reported. Usually discovered during the first months of life, CPC is characterised by a definitive bone defect in the middle third of the clavicle. Generally asymptomatic, the pseudarthrosis of the clavicle can cause aesthetic issues and functional symptoms indicating a surgical repair. Different reconstruction techniques have been reported with various complications. We present a 14-year-old boy diagnosed with CPC and concerned about the cosmetic aspect of a swelling of his right clavicle. We performed a two-stage surgical repair using the induced membrane technique described by Masquelet. A complete bone union has been obtained, and patient is satisfied with the cosmetic appearance. In our opinion, the Masquelet technique is a safe and reproducible procedure to treat CPC in high-risk older patients with long gap allowing a rapid and lasting bone union.
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Clavícula/anomalías , Seudoartrosis/congénito , Adolescente , Hilos Ortopédicos/normas , Clavícula/patología , Estética/psicología , Humanos , Masculino , Seudoartrosis/diagnóstico , Seudoartrosis/diagnóstico por imagen , Seudoartrosis/cirugía , Radiografía , Enfermedades Raras , Resultado del TratamientoRESUMEN
This study aimed to evaluate and compare two types of internal fixation, locking angular plate (group 1) and Kirschner-wires (group 2), for post-traumatic cubitus varus. The parameters used were Laupattarakasem's criteria (for range of motion in extension/flexion, correction of carrying angle, and the 'lazy S' deformity) and the Barrett's questionnaire (for patient satisfaction). In group I (plate+screws), we had three excellent results and five good. In group II (Kirschner-wires), we had two good results, three fair, and two poor. Statistical analysis showed a better outcome for group I (plate+screws) considering the correction of the humeral-elbow-wrist angle (P<0.003), the postoperative lateral prominence index (P<0.048), and the patient satisfaction (P<0.011). We recommend the locking angular plate, because it can rigidly stabilize the osteotomy, ensuring an excellent functional and cosmetic outcome.
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Placas Óseas/normas , Hilos Ortopédicos/normas , Lesiones de Codo , Articulación del Codo/cirugía , Osteotomía/instrumentación , Osteotomía/normas , Niño , Articulación del Codo/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Fijadores Internos/normas , Masculino , Estudios RetrospectivosRESUMEN
OBJECTIVES: This meta-analysis aimed to compare the therapeutic effect of mini-plate versus Kirschner wire (K-wire) internal fixation on the treatment of metacarpal and phalangeal fractures among Chinese Han population. METHODS: Databases of China National Knowledge Infrastructure (CNKI), Wanfang, Chinese VIP, PubMed, and Embase were retrieved for studies on mini-plate (case group) versus K-wire (control group) internal fixation for the treatment of metacarpal and phalangeal fractures among Chinese Han population. The odds ratio (OR) and standardized mean difference (SMD) at 95% confidence interval (CI) were used for estimating the effects of dichotomous data and continuous data, respectively. All statistical analyses were performed by Review Manager 5.2 software. RESULTS: A total of 18 studies involving 1,375 metacarpal or phalangeal fracture patients (709 cases and 666 controls) were included in the meta-analysis. There were significant differences in fracture healing time (SMD = -1.28; 95% CI: -1.81, -0.76), postoperative infection rate (OR = 0.25; 95% CI: 0.16, 0.39), complication incidence (OR = 0.24; 95% CI: 0.15, 0.38), and surgery time (SMD = 1.57; 95% CI: 0.76, 2.37) between the case and the control group, while no significant difference was found in hospital stays between these two groups (SMD = 0.43; 95% CI: -0.34, 1.20; P = 0.27). CONCLUSIONS: For the treatment of metacarpal or phalangeal fracture among Chinese Han population, mini-plate has advantages of shorter healing time and lower infection rate and complication incidence compared with K-wire internal fixation, while a longer surgery time than K-wire. In conclusion, mini-plate is prior than K-wire internal fixation for the treatment of metacarpal or phalangeal fracture among Chinese Han population.
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Placas Óseas , Hilos Ortopédicos , Falanges de los Dedos de la Mano/cirugía , Fijación Interna de Fracturas/instrumentación , Fracturas Óseas/cirugía , Huesos del Metacarpo/cirugía , Pueblo Asiatico/etnología , Placas Óseas/normas , Hilos Ortopédicos/normas , Falanges de los Dedos de la Mano/lesiones , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/normas , Fracturas Óseas/etnología , Humanos , Huesos del Metacarpo/lesiones , Vigilancia de la Población , Resultado del TratamientoRESUMEN
OBJECTIVE: To determine mechanical properties of various prosthetic materials secured to cadaveric canine femurs via various methods and to compare results with those for isolated loops of prosthetic material. SAMPLE: 80 femurs obtained from cadavers of skeletally mature large-breed dogs. PROCEDURES: 10 femoral constructs in each of 8 groups (single circumfabellar loop of polyethylene cord, double loop of polyethylene tape secured via a bone anchor [BAPT], single or double circumfabellar loops of nylon leader material [CNL] or polyethylene tape [CPT], or single or double loops of polyethylene tape secured via a toggle placed through a bone tunnel [BTPT]) and 10 isolated loops of prosthetic material in each corresponding configuration were tested. Stress relaxation, creep, elongation, load at 3 mm of displacement, stiffness, and peak load at failure were determined. RESULTS: 5 single CNL constructs failed before completion of testing. Double CNL and single circumfabellar polyethylene cord constructs had the lowest loads at 3 mm of displacement. Single and double CPT constructs had the highest stiffness. Double BTPT and CPT constructs had the highest peak loads at failure. Double BTPT, double CPT, and BAPT constructs were mechanically superior on the basis of lower creep and stress relaxation and higher stiffness and load at 3 mm of displacement versus other constructs. Stiffness of femoral constructs was 28% to 69% that of corresponding isolated prosthetic loops. CONCLUSIONS AND CLINICAL RELEVANCE: Double BTPT, double CPT, and BAPT constructs were mechanically superior to other constucts. Mechanical properties and methods of anchorage and securing of free ends of prostheses contributed to mechanical properties of constructs.
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Ligamento Cruzado Anterior/cirugía , Enfermedades de los Perros/cirugía , Fémur/cirugía , Rodilla de Cuadrúpedos/cirugía , Dispositivos de Fijación Quirúrgicos/veterinaria , Animales , Fenómenos Biomecánicos , Hilos Ortopédicos/normas , Hilos Ortopédicos/veterinaria , Cadáver , Perros , Falla de Equipo/veterinaria , Prótesis Articulares/veterinaria , Cinta Quirúrgica/veterinaria , Anclas para Sutura/normas , Anclas para Sutura/veterinaria , Resistencia a la TracciónRESUMEN
OBJECTIVE: The aim of the present study was to assess the quality of treatment using two reduction and fixation techniques for zygoma fractures. PATIENTS AND METHODS: A randomized clinical trial was carried out involving a sample of 10 patients with Knight and North type III, IV and V zygoma fractures divided into two groups. One group underwent the closed reduction technique and fixation with Kirschner wire and the other group underwent the open reduction technique and fixation with titanium plates. The groups were submitted to subjective evaluation based on the patient's perception of areas of deformity and paresthesia as well as the measurement of range of mouth opening and pain upon mouth opening in the preoperative (T0) and postoperative (T1) periods. The assessment of bone reduction quality was performed using quantifiable points (lateral wall of the orbit, anteroposterior projection of the zygoma and ocular globe projection), measured based on tomographic images. RESULTS: Seventy percent of the patients remained with paresthesia and 20% remained with the complaint of deformity at T1. Mouth opening range increased in both groups at T1. In the overall sample, mean total disjunction of the lateral wall of the orbit and the difference in the anteroposterior projection of the zygoma were reduced between T0 and T1 (4.36 mm to 1.25 mm and 6.94 mm to 2.86 mm, respectively). There was also a reduction in ocular globe projection in both groups between T0 and T1. CONCLUSIONS: Both techniques achieved adequate reduction of zygoma fractures in the postoperative period.
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Materiales Biocompatibles/química , Placas Óseas , Hilos Ortopédicos , Fijación Interna de Fracturas/métodos , Titanio/química , Fracturas Cigomáticas/cirugía , Adulto , Factores de Edad , Placas Óseas/normas , Hilos Ortopédicos/normas , Exoftalmia/etiología , Ojo/diagnóstico por imagen , Ojo/patología , Estudios de Seguimiento , Fijación de Fractura/instrumentación , Fijación de Fractura/métodos , Fijación Interna de Fracturas/instrumentación , Humanos , Persona de Mediana Edad , Tomografía Computarizada Multidetector , Órbita/diagnóstico por imagen , Órbita/patología , Dolor Postoperatorio/etiología , Parestesia/etiología , Satisfacción del Paciente , Complicaciones Posoperatorias , Rango del Movimiento Articular/fisiología , Articulación Temporomandibular/fisiopatología , Resultado del Tratamiento , Cigoma/diagnóstico por imagen , Cigoma/patologíaRESUMEN
OBJECTIVE: To compare the tensile strength and stiffness of non-absorbable suture loops created with two types of crimping devices. METHODS: Loops of monofilament nylon leader line (MN) of 18 kg, 36 kg, and 45 kg multifilament polyethylene (MP) with a crimp and MP with a crimp and knot were mechanically tested to failure in quasistatic tensile loading after being created with either a wave pattern crimp device or three applications of a single crimp device. Each testing group consisted of five samples. Tensile loading to failure at a rate of 9.5 mm/s was used. Failure was defined as a sudden drop in the recorded force. RESULTS: All suture materials failed by breaking near the crimp tube with both crimp devices, with exception of the MP without knot, which slipped through the crimp tube using both devices. Sutures secured with the wave pattern crimping device were significantly stronger with a higher load yield, maximum load, displacement yield, failure displacement, and maximum displacement than the single crimp device. Loops of MP suture crimped by either device plus the addition of a surgeon's knot resulted in a significantly stronger construct than unknotted crimped MP constructs. Crimped MP combined with knot were significantly stiffer, but not stronger, than crimped 45 kg MN. CLINICAL SIGNIFICANCE: Performing extra- capsular repair for ruptured cranial cruciate ligaments with the wave pattern crimp system may result in lower failure rates due to the construct being significantly stronger than the single crimp system.
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Nylons , Polietileno , Rodilla de Cuadrúpedos/cirugía , Dispositivos de Fijación Quirúrgicos/veterinaria , Anclas para Sutura/veterinaria , Animales , Fenómenos Biomecánicos , Hilos Ortopédicos/normas , Hilos Ortopédicos/veterinaria , Perros , Ensayo de Materiales , Cinta Quirúrgica/veterinariaRESUMEN
BACKGROUND: Numerous innovative minimally invasive fusion and fixation techniques for the thoracolumbar spine have recently been developed. However, less-invasive approaches for accessing the posterior cervical spine surgery have been more elusive. One promising option for posterior cervical fixation is trans-facet screw placement. SURGICAL TECHNIQUE: This method allows for a screw to be inserted percutaneously through the articular (zygapophyseal) facet joint. This eliminates the need for a connecting rod between segments, which remains a major limitation of longer segment minimally invasive lateral mass screw-rod constructs. Surgery was successfully performed in three consecutive cases with the use of existing small fragment cancellous screws intended for orthopedic applications. CONCLUSIONS: In this report we describe an initial clinical experience with cervical trans-facet screws, which we found to be a technically feasible option in the subaxial cervical spine for truly percutaneous spinal fixation. However, until percutaneous bony fusion methods are developed, this approach is limited to the fixation application, such as supplementing an anterior fusion construct.
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Tornillos Óseos/normas , Vértebras Cervicales/cirugía , Fusión Vertebral/instrumentación , Fusión Vertebral/métodos , Espondilosis/cirugía , Hilos Ortopédicos/normas , Vértebras Cervicales/anatomía & histología , Vértebras Cervicales/diagnóstico por imagen , Fluoroscopía/métodos , Humanos , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Articulación Cigapofisaria/cirugíaRESUMEN
BACKGROUND: A weight-bearing platform applied at the distal end of an Ilizarov external frame allows patients with hindfoot transfixations, foot deformities or plantar skin lesions to bear weight. This leads to an indirect loading of the fracture or osteotomy site. However, the effect on the fracture/osteotomy site's motion or compressive loads is unknown. The aim of this study was to analyze the mechanical effects of a weight-bearing platform on the traditional all-wire, four-ring frame in comparison to a two-ring frame consisting of half-pins. METHODS: Two frame configurations, with either anatomically positioned wires or half-pins, were analyzed with and without a weight-bearing platform applied underneath the distal ring. Composite tibiae with a mid-diaphyseal osteotomy of 3.5 mm were used in all the experiments. An axial load was applied with the use of a universal test machine (UTS®). Interfragmentary movements, the relative movements of bone fragments and movements between rings were recorded using displacement transducers. Compressive loads at the osteotomy site were recorded with loading cells. RESULTS: Indirect loading with a weight-bearing platform altered the force transmission through the osteotomy. Indirect loading of the tibiae decreased the extent of the axial micro-motion by 50% under the applied weight load when compared to direct weight loading (p < 0.05). The half pin frame was 25% stiffer than the wire frame under both direct and indirect loading of the tibiae (p < 0.05). Compressive loads under indirect loading were reduced by 67% in the wire frame and by 57% in the half-pin frames compared to direct loading of the bones (p < 0.05). While axial loading in the wire frames resulted in plain axial movements at the site of the osteotomy, it was coupled with translational movements and angular displacements in the half pin mountings. This effect was more apparent in the case of indirect loading. CONCLUSIONS: A weight-bearing platform has substantial influence on the biomechanical performance of an Ilizarov external fixator. Half-pins induce greater stiffness to the Ilizarov external fixator and allow the usage of only one ring per bone segment, but shear stresses at the osteotomy under axial loading should be considered. The results allow an estimation of the size and direction of interfragmentary movements based on the extent of weight bearing.
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Fijadores Externos/normas , Técnica de Ilizarov/instrumentación , Osteotomía/instrumentación , Tibia/fisiología , Soporte de Peso/fisiología , Clavos Ortopédicos/normas , Hilos Ortopédicos/normas , Diseño de Equipo , Curación de Fractura/fisiología , Humanos , Estrés Mecánico , Fracturas de la Tibia/fisiopatología , Fracturas de la Tibia/cirugíaRESUMEN
OBJECTIVE: To compare biomechanical properties of 3 new generation polyethylene sutures (FiberTape [FT], FiberWire [FW], and OrthoFiber [OF]) with nylon leader line (NL) for use during extraarticular fixation of cranial cruciate deficient stifles. STUDY DESIGN: In vitro biomechanical testing of suture loops under monotonic tensile and cyclical loading until failure. SAMPLE POPULATION: Constructs of FT, FW, OF, and NL. METHODS: Twenty loops of each of 12 combinations of fixation and suture had monotonic tensile and cyclical loading. Two knotting techniques (square knot [SQ], slip knot [SL]) and a crimp clamp (CR) system were evaluated. Elongation, stiffness, and strength of constructs was tested. The main effects of group, loop material, and their interaction were evaluated. RESULTS: Knotted FT, FW, and OF had less elongation than knotted NL under monotonic tensile and cyclical loading. Under monotonic tensile loading, knotted FT and OF were stiffer than knotted NL. CR FT, CR FW, and CR OF were stiffer than CR NL and CR FT, CR FW, and CR OF were stiffer than knotted FT, FW, and OF. FW and OF knotted loops were weaker than knotted NL. CR FT was stronger than CR NL. CR FT and CR OF were weaker than knotted FT and OF. CONCLUSIONS: Polyethylene sutures are stronger, stiffer and elongate less than nylon leader. Crimping suture alters the biomechanical properties of the loop. CLINICAL RELEVANCE: FW, FT, and OF may perform better in reconstructive procedures, where increased strength and stiffness are considered to be beneficial.
Asunto(s)
Ligamento Cruzado Anterior/cirugía , Hilos Ortopédicos/veterinaria , Enfermedades de los Perros/cirugía , Rodilla de Cuadrúpedos/cirugía , Cinta Quirúrgica/veterinaria , Animales , Fenómenos Biomecánicos , Hilos Ortopédicos/normas , Perros , Falla de Equipo/veterinaria , Técnicas In Vitro , Nylons , Resistencia a la TracciónRESUMEN
BACKGROUND: This study evaluated intramedullary fixation of rib fractures with Kirschner wires and novel ribs splints. We hypothesized that rib splints can provide equivalent fixation strength while avoiding complications associated with Kirschner wires, namely wire migration and cutout. METHODS: The durability, strength, and failure modes of rib fracture fixation with Kirschner wires and rib splints were evaluated in 22 paired human ribs. First, intact ribs were loaded to failure to determine their strength. After fracture fixation with Kirschner wires and rib splints, fixation constructs were dynamically loaded to 360,000 cycles at five times the respiratory load to determine their durability. Finally, constructs were loaded to failure to determine residual strength and failure modes. RESULTS: All constructs sustained dynamic loading without failure. Dynamic loading caused three times more subsidence in Kirschner wire constructs (1.2 mm +/- 1.4 mm) than in rib splint constructs (0.4 mm +/- 0.2 mm, p = 0.09). After dynamic loading, rib splint constructs remained 48% stronger than Kirschner wire constructs (p = 0.001). Five of 11 Kirschner wire constructs failed catastrophically by cutting through the medial cortex, leading to complete loss of stability and wire migration through the lateral cortex. The remaining six constructs failed by wire bending. Rib splint constructs failed by development of fracture lines along the superior and interior cortices. No splint construct failed catastrophically, and all splint constructs retained functional reduction and fixation. CONCLUSIONS: Because of their superior strength and absence of catastrophic failure mode, rib splints can serve as an attractive alternative to Kirschner wires for intramedullary stabilization of rib fractures, especially in the case of posterior rib fractures where access for plating is limited.
Asunto(s)
Hilos Ortopédicos , Fijación Intramedular de Fracturas/instrumentación , Fracturas de las Costillas/cirugía , Anciano , Fenómenos Biomecánicos , Hilos Ortopédicos/efectos adversos , Hilos Ortopédicos/normas , Elasticidad , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Migración de Cuerpo Extraño/etiología , Fijación Intramedular de Fracturas/efectos adversos , Fijación Intramedular de Fracturas/métodos , Curación de Fractura , Humanos , Masculino , Ensayo de Materiales , Rotación , Férulas (Fijadores)/efectos adversos , Férulas (Fijadores)/normas , Resistencia a la Tracción , Soporte de PesoRESUMEN
BACKGROUND: The metal implants used to achieve fixation of displaced transverse patellar fractures are associated with implant failure, postoperative pain and a significant re-operation rate. Recent studies have examined braided suture as a possible alternative to stainless steel wire to increase patient satisfaction and decrease re-operation rates, but suture has not demonstrated clearly superior fixation strength. FiberWire is a reinforced braided polyblend suture that has demonstrated superior characteristics to the previous sutures studied and has not to our knowledge been examined as a material for tension band fixation of transverse patellar fractures. METHODS: Materials testing was performed on repeated samples of No. 5 FiberWire suture and 18-gauge stainless steel wire. The strength and stiffness of each material was measured. The two materials were then used for tension band fixation on a novel transverse patellar fracture model and tested to failure by three-point bending. The constructs included a single stainless steel wire, a single-strand FiberWire tied with a sliding knot, double-strand FiberWire tied with sliding knots and double-strand FiberWire tied with a Wagoner's Hitch. The fixation strength and stiffness of the constructs were measured. FINDINGS: Unlike stainless steel, FiberWire maintained its initial stiffness until failure. Furthermore, during three-point-bend testing, double-strand FiberWire was found to have a significantly higher failure load than stainless steel wire when the suture was tied and locked under the tension produced by a modified Wagoner's Hitch. INTERPRETATION: FiberWire is a potentially superior alternative to stainless steel wire in tension band fixation of transverse patellar fractures.
Asunto(s)
Hilos Ortopédicos/normas , Fijación Interna de Fracturas/instrumentación , Fracturas Óseas/cirugía , Ensayo de Materiales/métodos , Rótula/lesiones , Anciano , Humanos , Reoperación/estadística & datos numéricos , Acero Inoxidable , Técnicas de Sutura , Suturas , Resistencia a la Tracción , Resultado del TratamientoRESUMEN
OBJECTIVES: In this study, the divergent wire stretching method used to fix the fractured pieces in the Ilizarov technique is biomechanically compared with the olive wire fixation method. PATIENTS AND METHODS: Between 1999 and 2005, 36 tibial plateau fractures of 34 patients (27 males, 7 females; mean age 48.4; range 26 to 81 years) were treated with the Ilizarov technique. Divergent wire stretching technique was used in all cases. Patients were mobilized regardless of fracture type and with full load bearing in the shortest possible time after the operation. In the second stage of this study, in order to achieve interfragmentary compression, the reciprocal olive wire method was compared with the divergent wire stretching method developed by us on tibia models at the biomechanic laboratory. RESULTS: All cases were mobilized with full weight bearing at the early postoperative period. The fusion period was 14 weeks and fixators were removed at an average of 19 weeks. No deep infection was observed in any of the cases. No other surgical intervention was required for nonunion or reduction failure. More than 2 mm separation was detected in 12 cases during 24 weeks of observation. But this has not been considered to be clinically significant. In 29 cases, the knee range of motion was 0-135 degrees. In the biomechanical phase of the study, no distinct difference was observed between the classic olive wire stretching method and the divergent wire stretching method regarding the preservation of the interfragmentary compression under weight. The divergent wire stretching method was significantly superior in achieving an homogeneous interfragmentary compression. CONCLUSION: The divergent wire stretching technique applied parallel to the Ilizarov fixation technique is an effective method for the early and unrestricted mobilization of the patients and the preservation of the range-of-motion of the joint.