RESUMEN
BACKGROUND: Intramedullary clavicle fixation is a potential alternative to plate fixation. Previous studies documenting the complication rates of intramedullary clavicle fixation have demonstrated variable rates of soft tissue complications and fracture healing. QUESTIONS/PURPOSES: We asked the following questions: (1) Does use of the Rockwood Clavicle Pin (DePuy Orthopaedics Inc, Warsaw, IN) predispose patients to soft tissue complications requiring additional surgery or a high infection risk? (2) Does the Rockwood Clavicle Pin provide a truly minimally invasive insertion technique and reliable fracture fixation? PATIENTS AND METHODS: We retrospectively evaluated 18 patients (mean age, 31 years) who sustained a closed midshaft fracture of the clavicle treated with open intramedullary nailing with a Rockwood Clavicle Pin. We determined the incidence of complications and rate of fracture healing. RESULTS: Fourteen complications occurred in 10 patients. Five patients experienced a complication with fracture healing, including three nonunions. Nine patients experienced complications relating to soft tissue, including infection, skin necrosis, or posterior pain from pin prominence. CONCLUSIONS: The Rockwood Clavicle Pin remains a historically relevant method of clavicle fixation. However, due to an unacceptably high rate of nonunion, repeat operation, and soft tissue complications, we do not recommend this device for treating middiaphyseal clavicle fractures. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
Asunto(s)
Clavos Ortopédicos , Clavícula/lesiones , Fijación Intramedular de Fracturas/efectos adversos , Fracturas Óseas/cirugía , Adolescente , Adulto , Clavícula/diagnóstico por imagen , Desbridamiento , Diseño de Equipo , Femenino , Curación de Fractura , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Estudios Retrospectivos , Traumatismos de los Tejidos Blandos/etiología , Adulto JovenRESUMEN
STUDY DESIGN: This study is a biomechanical analysis of intervertebral cage placement, using a biomechanical model that has the appropriate matching geometry of the lumbar spine at the level of L4-L5 based upon prior morphometric studies. OBJECTIVE: The goal of this in vitro biomechanical analysis of interbody cages is to determine the effect of interbody cage position on the mechanics of posterior spinal instrumentation. This biomechanical analysis can potentially be used to guide surgical technique for placement of interbody cage devices. SUMMARY OF BACKGROUND DATA: Lumbar interbody spinal fusion cages are increasingly being used to promote spinal fusion and improve sagittal alignment in patients with degenerative disk disease. The transforaminal approach for placement of these cages has become popular, although the actual position of the cage that will provide optimal mechanical support in the intervertebral space is not known. MATERIALS AND METHODS: Leopard carbon fiber interbody cages (DepuySpine, Raynham, MA) were placed in a spinal fusion model simulating the L4-L5 disk space in one of 3 positions-anterior, middle, or anterolateral. We tested 5 constructs in each of the 3 positions, applying cyclic axial loads of 500 N at a rate of 4 Hz for 100,000 cycles. Strain on the posterior instrumentation and displacement of the cages was measured at periodic intervals. Load to failure of each construct was tested after 100,000 cycles were complete. RESULTS: Statistical analysis of biomechanical indicators show more strain in the anterolateral position as compared with the anterior position (P=0.002) and middle position (P=0.02). No difference was noted between anterior and middle positions (P=1.00). Interval analysis reveals differences in strain at 500 cycles in anterior versus anterolateral (P=0.01) and middle versus anterolateral (P=0.02). At 10,000 cycles, anterolateral strain was significantly higher (P=0.02) than anterior. No significant difference in strain was noted at 50,000 or 100,000 cycles between any of the positions. No significant differences were noted in displacement of the cages between each of the positions. Ultimate load to failure was lower (nonsignificant) in the anterolateral versus anterior position (P=0.06), but no difference was noted between anterior versus middle (P=0.57) or anterolateral versus middle (P=0.69) positions. Linear regression analysis of load-displacement curves shows significance at 500 cycles (P=0.02), approaching significance at 10,000 cycles (P=0.07), and no significant difference at 50,000 (P=0.28) or 100,000 (P=0.28) cycles. CONCLUSIONS: Positioning of interbody cages in an offset position shows higher strain upon posterior instrumentation than a central position, and quicker load to failure than an anteriorly placed cage. Biomechanical studies using shear loading, and testing of adjacent spinal levels, are necessary to further elucidate the biomechanical consequences of variable positioning of interbody cages.
Asunto(s)
Carbono , Modelos Teóricos , Dispositivos de Fijación Ortopédica , Prótesis e Implantes , Fenómenos Biomecánicos , Fibra de Carbono , Humanos , Técnicas In Vitro , Vértebras Lumbares/cirugía , Ensayo de Materiales , Diseño de Prótesis , Fusión Vertebral/métodosRESUMEN
STUDY DESIGN: A case report and review of the literature are presented. OBJECTIVES: To describe the clinical course and treatment of a patient with an unusual intraosseous degenerative cyst within the body of the axis, as well as review the literature regarding these lesions. SUMMARY OF BACKGROUND DATA: Intraosseous degenerative cysts of the cervical spine are extremely rare. To our knowledge, only 4 prior case studies have described these lesions, 2 of which were seen in the body of C2. METHODS: A case report of a 58-year-old patient with neck pain and an intraosseous cyst within the axis is presented with a review of the pertinent literature. RESULTS: History, examination, radiographic evaluation, and histology revealed this lesion to be an intraosseous degenerative cyst within the body of C2. The patient was treated with anterior surgical biopsy/curettage and posterior stabilization with structural graft enhancement. CONCLUSION: Although rare, intraosseous cervical degenerative cysts should be present in any differential diagnosis of cystic lesions seen in the cervical spine.
Asunto(s)
Quistes Óseos/diagnóstico por imagen , Vértebras Cervicales/diagnóstico por imagen , Quistes Óseos/diagnóstico , Quistes Óseos/cirugía , Vértebras Cervicales/cirugía , Humanos , Masculino , Persona de Mediana Edad , RadiografíaRESUMEN
BACKGROUND: The number of spinal cord injuries due to gunshot wounds continues to rise each year, and they currently rank third behind motor vehicle collisions and falls. Spine and wound infections pose difficult problems for transgastrointestinal gunshot wounds to the spine. METHODS: A retrospective review of 114 patients with low-velocity gunshot wounds to the spine was performed. Attention was paid to associated gastrointestinal (GI) tract injuries, antibiotic coverage, surgical intervention, and the development of spine and wound infections. RESULTS: Of 114 patients with gunshot wounds to the spine, 27 (23.7%) sustained a concomitant GI tract injury and 87 (76.3%) did not. Four spine infections (4/114, 3.5%) and 23 wound infections (23/114, 20.2%) developed in our patient population. Spine infection (chi = 13.36, p < 0.001) and wound infection (chi = 12.94, p < 0.001) rates were significantly higher in transgastrointestinal gunshot wounds to the spine. Surgical treatment of the spine in patients with transgastrointestinal gunshot wounds showed a significantly higher rate of spinal infection than did nonsurgical treatment of the spine (p = 0.013, Cramer's V = 0.61). No significant difference in spine infection rate was seen with adequate versus inadequate antibiotic coverage in the trans- gastrointestinal subset (p = 1.00), or in the development of wound infections with spine surgery (p = 0.628) or varying antibiotic coverage (p = 1.00). CONCLUSIONS: There is a significantly higher rate of spine and wound infections with trans-gastrointestinal gunshot wounds to the spine. These injuries, particularly those that involve the colon, put patients at risk for the development of spine infections after spinal surgery. Randomized controlled trials are necessary for the development of a specific protocol for intravenous antibiotic therapy in the setting of transgastrointestinal gunshot wounds to the spine.