Are routine postoperative radiographs necessary during the first year after posterior spinal fusion for idiopathic scoliosis? A retrospective cohort analysis of implant failure and surgery revision rates.

BACKGROUND: Radiographs are routinely obtained at postoperative visits during the first year after posterior spinal fusion (PSF) for idiopathic scoliosis (IS). The goal of this study was to determine how often radiographic findings change postoperative care. METHODS: A total of 227 consecutive patients aged 10 to 21 years who underwent surgery for IS at our institution from 2004 to 2010 were identified. Charts were reviewed to determine the frequency of the following clinical symptoms during the first year after surgery: pain greater than expected, implant prominence, and sensory/motor disturbance. Radiographs were reviewed to identify implant failure and curve change. Logistic regression analysis was used to identify clinical symptoms associated with treatment deviation. RESULTS: During the first year after surgery, an average of 6 (range, 2 to 12) radiographs were obtained from patients during an average of 3 (range, 2 to 10) follow-up visits. Pain (14%) was the most common symptom. Neurologic symptoms (13%) and implant prominence (4%) were less common. Implant failure was identified in 4 subjects (2%), of which 3 required revision surgery. The incidence of revision surgery was 2.9/1000 radiographs (95% confidence interval, 0.6-8.3). Curve progression >5 degrees in the uninstrumented curve occurred in 2 patients (0.9%). Curve progression did not result in a change in treatment for any of the patients. Pain was the only clinical symptom associated with implant failure (P=0.0047). 169/227 patients did not have any symptoms and only one of these underwent revision surgery. The sensitivity of a clinical test, which uses the presence of pain to guide the need for radiographic evaluation and rule out implant failure, was 75%, specificity 87%, positive predictive value 10%, and negative predictive value 99.5%. CONCLUSIONS: After obtaining baseline postoperative radiographs, additional radiographs during the first year after surgery for IS may not be required in the absence of clinical symptoms. Reducing the number of radiographs taken during the first year after surgery for IS in patients without symptoms can reduce radiation exposure to patients and health care costs without affecting treatment. LEVEL OF EVIDENCE: Level II, Diagnostic Study.

Perfect--the enemy of good.

Our article has limitations, which we thoroughly describe. However, as the article highlights, wheelchairs are requiring repairs much too often, the repairs are causing significant consequences for users, and the problem is getting worse. The commentary concludes that producing a strong study will be difficult and of limited value, but offers no call for better, larger studies or suggestions for improvements. We believe there is much to be learned from our data, and our conclusion is that we need to do better. We need more information, larger cohorts, and better methods. It is the best way to cause changes that will positively impact the millions of wheelchair users around the world.

Plunging when drilling: effect of using blunt drill bits.

OBJECTIVE: Plunging when drilling can be a detrimental factor in patient care. There is, although, a general lack of information regarding the surgeon's performance in this skill. The aim of this study was to determine the effect that using sharp or blunt instruments had on the drill bit's soft tissue penetration, using a simulator. MATERIALS AND METHODS: Surgeons taking part in an International Trauma Course were invited to participate. Two groups were defined: experienced and inexperienced surgeons. Twelve holes were drilled in the following order: 3 holes with a sharp drill bit in normal bone (SNB), 3 holes with a sharp drill bit in osteoporotic bone (SOB), 3 holes with a blunt drill bit in normal bone, and 3 holes with a blunt drill bit in osteoporotic bone. Mean values and Student t tests were used for statistical analysis. RESULTS: Thirty-seven surgeons participated, 20 experienced and 17 inexperienced surgeons. Mean plunging depths for SNB, SOB, blunt drill bit in normal bone, and blunt drill bit in osteoporotic bone were, respectively, 5.1, 5.4, 21.1, and 13.9 mm for experienced surgeons and 7.6, 7.7, 22, and 15.9 mm for inexperienced surgeons. Drilling with SNB and with SOB was statistically different, with inexperienced surgeons plunging 2.5 mm (P = 0.31) and 2.6 mm (P = 0.042) deeper, respectively. There was a difference (P < 0.001) between sharp and blunt drill bits in all drilling conditions for both the groups. CONCLUSIONS: Our study showed a significant difference in plunging depth when sharp or bunt drill bit was being used. Surgeons, regardless of their experience level, penetrate over 20 mm in normal bone and over 10 mm in osteoporotic bone.

Diseño personalizado de una interfaz mioeléctrica para una prótesis de miembro superior / Custom design of a myoelectric interface for upper limb prostheses

Desde los años sesenta se utilizan las señales electromoigráficas (EMG) como señales de control para prótesis actuadas por servomotores, así como en la estimulación de músculos que sufren de parálisis o de atrofia parcial. Mediante el avance tecnológico se ha logrado mejorar el diseño, así como la fabricación de sistemas protésicos, que funcionan como extensiones de algún miembro del cuerpo humano, agregando además con los nuevos diseños, características básicas como: flexibilidad, estética morfológica, incremento de la relación resistencia/peso así como multifuncionalidad. Una prótesis mioeléctrica es una estructura desarrollada con el fin de reemplazar una parte o la totalidad de un miembro del cuerpo humano, lo mismo que suplir las funciones perdidas de este, sin dejar de lado la imagen corporal del paciente. Estas prótesis son accionadas por actuadores que se controlan a través de señales EMG, las cuales se obtiene mediante agujas intramusculares superficiales o por medio de electrodos colocados en el muñón del paciente. Este tipo de prótesis es cada vez más aceptado por personas con amputación de mano, ya que proporciona un mejor desempeño y permite el incremento de funcionalidad para el paciente que la utiliza, debido a que su control es más sencillo.

Since 60’s electromiographical signals (EMG’s) are used like a control signals for prostheses acted by servomotors, as well as stimulation of muscles that are affected due to partial or total paralysis. By means of technological advance, it has been possible to improve the design as well as the production of prosthetic systems that work as extensions of some member of human body, adding with the new designs also basic characteristics as: flexibility, aesthetic morphology, and superior strength/weight relationship, as well as multi-functionality. Mioelectric prosthesis is a structure developed with the purpose of replacing a part or the entirety member of human body, same as to replace the lost functions of this, without leaving aside patient's corporal image. These prostheses are acted by actuators that are controlled through EMG signals, which are obtained by means of intramuscular or superficial needles, or by means of electrodes placed in patient's stump. This class of prostheses is more and more accepted by people with hand amputation since it provides a better acting, that which allows a superior functionality for patient that uses it, because its control is simpler.