Abstract. Objectives. Single-event multilevel surgery (SEMLS) is the standard orthopaedic treatment for gait abnormalities in children with diplegic cerebral palsy (CP). The primary aim of this study was to report the long-term functional mobility of these patients after surgery. The secondary aim was to assess the relationship between functional mobility and quality of life (QoL). Methods. Patients were included if they met the following criteria: 1) diplegic CP; 2) Gross Motor Function Classification System (GMFCS) I to III; 3) SEMLS at age ≤ 18. A total of 61 patients, mean age at surgery 11 years eight months (SD 2y 5m), were included. A mean of eight years (SD 3y 10m) after SEMLS, patients were contacted and asked to complete the Functional Mobility Scale (FMS) questionnaire over the telephone and given a weblink to complete an online version of the CP QOL Teen. FMS was recorded for all patients and CP QOL Teen for 23 patients (38%). Results. Of patients graded GMFCS I and II preoperatively, at long-term follow-up the proportion walking independently at home, school/work and in the community was 71% (20/28), 57% (16/28) and 57% (16/28), respectively. Of patients graded GMFCS III preoperatively, at long-term follow-up 82% (27/33) and 76% (25/33) were walking either independently or with an
Despite the increasing use on uncemented implants, cement continues to be used for hip and knee replacement in both primary and revision cases. Whilst the exact clinical relevance of reducing cement porosity, and thereby increasing its strength, is unclear in such applications, successive generations of mixing and implanting have all concentrated on reducing the amount of air in cement. The aim of the present study was to elucidate whether the use of a power tool mixing device could reduce cement porosity more than the use of mixing under vacuum conditions alone. Furthermore, we determined if variability in cement porosity could also be reduced with power tool mixing compared with hand mixing under vacuum conditions. Cement was mixed in three different ways in a Stryker cement mixing cartridge. For group 1, cement was mixed by hand with no vacuum. For group 2, cement was mixed manually under vacuum. For group 3, cement was mixed under vacuum using the Stryker Revolution system. For all three groups, cement was stored and mixed at the same temperature and humidity. To study cement porosity, we used 3-dimensional computerised microtomography, a technique which has previously been used by other investigators. Porosity for the sample in group 1 was 9.4%, and for groups 2 and 3, mean sample porosity was 1.8% (SD 1.3) and 1.1% (SD 1.0) respectively. The large difference in porosity between group 1 and the other groups was evident on visual examination. These pores were absent when vacuum was applied. This confirms the results of several studies that have shown significant cement porosity under non-vacuum mixing conditions, even when there is strict adherence to mixing methods. Under vacuum conditions, using the Stryker Revolution system, further small reduction in cement porosity was achieved compared with manual mixing. Both Groups 2 and 3 showed variations in porosity between specimens from the same batch (intra-batch) and between batches (inter-batch). Individual specimens also demonstrated regional variations in internal porosity. Whilst the absolute reduction in overall porosity was small between the two groups (0.7%), the results favoured mixing using a rotary power tool. In addition the Revolution device was of great benefit from an ergonomic perspective. It enabled low porosity specimens to be mixed with greater ease, homogeneity and reproducibility than with manual mixing. Using the Revolution device was operator independent and involved less effort. This is likely to be of benefit in the operating room. In current practice, staff members often do not work with the same surgical team on a repeated basis, so the surgeon is likely to get greater cement consistency with such a device. It is likely to be easier to mix cement well for less experienced members of the surgical scrub team. Whilst an experience operator may be able to produce a mix of cement with very low porosity by manual mixing, it is still likely to be higher than one mixed using a power
