The perception of psychosocial risks through the HSE questionnaire of a population of neurophysiology technicians: a cross-sectional study.

OBJECTIVES: The Neurophysiopathology Technicians (NTs) are exposed to psychosocial risks, exposure to psychosocial risks that cause related work stress has been related to numerous physical and mental illnesses. The aim of this study is to evaluate the perception of psychosocial risks in a population of this population. MATERIALS AND METHODS: 54 technicians of Neurophysiopathology were enrolled, consisting of 23 males (42,6 %) and 31 females (57,4 %). All subjects were administered the HSE questionnaire developed by the Health and Safety Executive. the statistical analysis provided for the assessment of the reliability of the questionnaires and the non-parametric analysis of gender differences. RESULTS: In the total population emerges as critical the perception of the domain "Managers' Support" with Cronbach's alpha values for total males and females respectively of 0,87, 0,85, 0,88. In the female population is added the critical perception of the "Peer Support" domain (p=0,026), shows that the employees indicated that they do not receive adequate information and support from their colleagues. DISCUSSION: The study highlights the exposure to psychosocial risks by technicians of neurophysiopathology able to mediate the phenomenon of WRS. The HSE questionnaire represents a tool capable of highlighting specific risks to which workers are exposed. Furthermore, its ability to capture elements of the work context significantly increases if an analysis is carried out that takes into account the worker's gender.

Tibial component alignment and risk of loosening in unicompartmental knee arthroplasty: a radiographic and radiostereometric study.

PURPOSE: Unicompartmental knee arthroplasty (UKA) has shown a higher rate of revision compared with total knee arthroplasty. The success of UKA depends on prosthesis component alignment, fixation and soft tissue integrity. The tibial cut is the crucial surgical step. The hypothesis of the present study is that tibial component malalignment is correlated with its risk of loosening in UKA. METHODS: This study was performed in twenty-three patients undergoing primary cemented unicompartmental knee arthroplasties. Translations and rotations of the tibial component and the maximum total point motion (MTPM) were measured using radiostereometric analysis at 3, 6, 12 and 24 months. Standard radiological evaluations were also performed immediately before and after surgery. Varus/valgus and posterior slope of the tibial component and tibial-femoral axes were correlated with radiostereometric micro-motion. A survival analysis was also performed at an average of 5.9 years by contacting patients by phone. RESULTS: Varus alignment of the tibial component was significantly correlated with MTPM, anterior tibial sinking, varus rotation and anterior and medial translations from radiostereometry. The posterior slope of the tibial component was correlated with external rotation. The survival rate at an average of 5.9 years was 89%. The two patients who underwent revision presented a tibial component varus angle of 10° for both. CONCLUSIONS: There is correlation between varus orientation of the tibial component and MTPM from radiostereometry in unicompartmental knee arthroplasties. Particularly, a misalignment in varus larger than 5° could lead to risk of loosening the tibial component. LEVEL OF EVIDENCE: Prognostic studies-retrospective study, Level II.

Tibio-femoral and patello-femoral joint kinematics during navigated total knee arthroplasty with patellar resurfacing.

PURPOSE: In total knee arthroplasty, surgical navigation systems provide tibio-femoral joint (TFJ) tracking for relevant bone preparation, disregarding the patello-femoral joint (PFJ). Therefore, the important intra-operative assessment of the effect of component positioning, including the patella, on the kinematics of these two joints is not available. The objective of this study is to explore in vivo whether accurate tracking of the patella can result in a more physiological TFJ and PFJ kinematics during surgery. METHODS: Ten patients underwent navigated knee replacement with patellar resurfacing. A secondary system was used to track patellar motion and PFJ kinematics using a special tracker. Patellar resection plane position and orientation were recorded using an instrumented probe. During all surgical steps, PFJ kinematics was measured in addition to TFJ kinematics. RESULTS: Abnormal PFJ motion patterns were observed pre-operatively at the impaired knee. Patellar resection plane orientation on sagittal and transverse planes of 3.9° ± 9.0° and 0.4° ± 4.1° was found. A good restoration of both TFJ and PFJ kinematics was observed in all replaced knees after resurfacing, in particular the rotations in the three anatomical planes and medio-lateral patellar translation. CONCLUSIONS: Patella tracking results in nearly physiological TFJ and PFJ kinematics in navigated knee arthroplasty with resurfacing. The intra-operative availability also of PFJ kinematics can support the positioning not only of the patellar component in case of resurfacing, but also of femoral and tibial components.

Three-dimensional motion analysis of the human knee joint: comparison between intra- and post-operative measurements.

PURPOSE: To compare intra-operative knee joint kinematic measurements immediately after total knee replacement with those of the same patients post-operatively at 6-month follow-up. METHODS: Fifteen patients who underwent total knee arthroplasty were analysed retrospectively. Eight were implanted with one prosthesis design and seven with another. The intra-operative measurements were performed by using a standard knee navigation system. This provided accurate three-dimensional positions and orientations for the femur and tibia by corresponding trackers pinned into the bones. At 6-month follow-up, the patients were analysed by standard three-dimensional video-fluoroscopy of the replaced knee during stair climbing, chair rising and step-up. Relevant three-dimensional positions and orientations were obtained by an iterative shape-matching procedure between the silhouette contours and the CAD-model projections. A number of traditional kinematic parameters were calculated from both measurements to represent the joint motion. RESULTS: Good post-operative replication of the intra-operative measurements was observed for most of the variables analysed. The statistical analysis also supported the good consistency between the intra- and post-operative measurements. CONCLUSIONS: Intra-operative kinematic measurements, accessible by a surgical navigation system, are predictive of the following motion performance of the replaced knees as experienced in typical activities of daily living. LEVEL OF EVIDENCE: Prognostic studies--investigating natural history and evaluating the effect of a patient characteristic, Level II.

Geometrical changes of knee ligaments and patellar tendon during passive flexion.

Patterns of fibre elongation and orientation for the cruciate and collateral ligaments of the human knee joint and for the patellar tendon have not yet been established in three-dimensions. These patterns are essential for understanding thoroughly the contribution of these soft tissues to joint function and of value in surgical treatments for a more conscious assessment of the knee status. Measurements from 10 normal cadaver knees are here reported using an accurate surgical navigation system and consistent anatomical references, over a large flexion arc, and according to current recommended conventions. The contours of relevant sub-bundles were digitised over the corresponding origins and insertions on the bones. Representative fibres were calculated as the straight line segments joining the centroids of these attachment areas. The most isometric fibre was also taken as that whose attachment points were at the minimum change in length over the flexion arc. Changes in length and orientation of these fibres were reported versus the flexion angle. A good general repeatability of intra- and inter-specimens was found. Isometric fibres were found in the locations reported in the literature. During knee flexion, ligament sub-bundles slacken in the anterior cruciate ligament, and in the medial and lateral collateral ligaments, whereas they tighten in the posterior cruciate ligament. In each cruciate ligament the two compounding sub-bundles have different extents for the change in fibre length, and also bend differently from each other on both tibial planes. In the collateral ligaments and patellar tendon all fibres bend posteriorly. Patellar tendon underwent complex changes in length and orientation, on both the tibial sagittal and frontal planes. For the first time thorough and consistent patterns of geometrical changes are provided for the main knee ligaments and tendons after careful fibre mapping.

Powered wheelchairs and independence in young children with tetraplegia.

The aim of this study was to assess the effect of early provision (< or = 8 years) of a powered wheelchair (PWC) in children with tetraplegia. Twenty-nine children (15 males, 14 females; mean age 6 years 3 months, age range 3 to 8 years) with spastic or dystonic tetraplegia were studied. All participants had severe motor impairment. Treatment outcomes were investigated in several dimensions of disablement: Impairment, Functional Limitation/Activity, Disability/Participation. It was found that the level of independence improved significantly after PWC provision, while motor impairment, IQ, and quality of life did not. The majority of children (21 of 27) reached a level of driving competence which allowed them to move around with or without minimal (i.e. verbal) adult support. Achievement of this competence was not statistically related to IQ or motor impairment but correlated to the time spent in the PWC. The majority of parents (21 of 25) were not in favour of the PWC when the study started but after PWC provision, 23 of 25 parents expressed positive feelings about it. Reactions of the majority of children (23 of 25) were positive from the beginning of the study and did not change over time. The authors concluded that PWCs can aid independence and socialization and the majority of children can achieve a good-enough driving competence, even those with severe learning disability or motor deficit. PWCs should not be viewed as a last resort but as a means of providing efficient self-locomotion in children with a severe motor deficit.

Functional status of adults with cerebral palsy and implications for treatment of children.

This study examined the evolution of individuals with cerebral palsy (CP) from childhood to adulthood. Seventy-two adults with a diagnosis of CP born between 1934 and 1980 were studied. Individuals were recruited and data comprehensively collected using case notes and through direct assessments of the majority of participants from three rehabilitation units in Bologna, Padua, and Rovigo in Italy. The main findings can be summarized as follows: contact with health and rehabilitation services was radically reduced once individuals reached adulthood; more individuals who were integrated into mainstream schools achieved and maintained literacy than those who had attended special schools; in a high number of participants, motor performance deteriorated once into adulthood. Independent walking or other forms of supported locomotion were lost in many on reaching adulthood. Of those who continued to walk, walking deteriorated in terms of distance. It was concluded that even though CP has been considered as predominantly a childhood pathological condition, the evolution of the effects of CP do not stop at 16 or 18 years of age. For this reason, the traditional child- (or infant-) oriented approach concentrating mainly or exclusively on the achievement of independent walking, may not be an ideal approach to children with CP. Instead a more independence-oriented therapeutic approach would be appropriate.