Summary

There is tremendous variability amongst surgeons' ability to reference anatomic landmarks. This may suggest the necessity of other objective methods in determining femoral alignment and rotation.

Introduction: There is an increasing appreciation of the potential impact of ethnic and gender diversity on access to healthcare. Previous studies have shown that both race and gender are important confounding factors. In this study we isolate the influence of ethnicity on the functional outcome of total knee replacement by examining outcomes in female patients.

Materials and Methods: We reviewed a data-base of 412 female patients (518 knees) who had undergone primary TKA performed by a single surgeon between 1990 and 2008. Eighty-seven of these patients (25 African-American, 23 Hispanic and 26 Caucasian patients) were case-matched for age and BMI at the time of surgery. The average patient age was 67.0 years with a BMI of 32.0. The groups showed no statistical different in age (p=0.99) or BMI (p=0.90). Preoperative and postoperative Knee Society scores were available on all patients in addition to marital status. Outcome measures of all three groups were compared using ANOVA statistical methods with post hoc analysis.

Results: Post-op Knee Society Scores were Significantly lower in the African-American patients (76.2, p=0.02) than the Hispanic (85.1) and Caucasian (87.9) groups. There was also a Significant difference in post-op pain scores for African-American, Hispanic, and Caucasian patients were 32.2, 40.3, and 42.8 respectively, (p=0.02) showing a statistically Significant difference between groups. The average Function Score was also lower in both African-American (61.1) and Hispanic (63.3) groups when compared to Caucasian (72.1) but this difference was not statistically Significant (p=0.09, p=0.25). There was no Significant difference in preoperative knee scores, post-op ROM or stability, or marital status among the three groups (p > .05).

Discussion:

Within the female population, ethnicity was shown to have a Significant influence on the outcome of TKA as inferior results were reported by both Hispanic and African-American patients when compared to Caucasians. This effect is particularly marked in African-American women whose Knee Society Scores were 13% lower at follow-up compared to Caucasians.

Introduction: The purpose of this study was to quantify changes in lower limb muscle strength in children with spastic diplegic cerebral palsy 6 months after multi-level orthopaedic surgery.

Method: A consecutive sample of 20 children ( 10 girls and 10 boys, mean age 10.6) with spastic diplegia was studied prospectively. All participants had soft-tissue and bony surgical procedures performed as part of their clinical management. Physiotherapy treatment commenced following surgery. Lower limb muscle strength, pre and 6 months post-surgery, was measured, in addition to routine gait and function assessment. Maximum voluntary isometric strength of 5 muscle groups was measured bilaterally using a digital dynamometer. Paired-samples t-tests were performed.

Results: There was a marked deterioration of muscle strength (p < 0.05) in all muscle groups. Medial hamstrings and hip flexors showed the greatest decline with an average decrease of 54% and 41% respectively. Analysis of gait parameters showed a significant improvement in kinematics (p< 0.05) but a decrease in walking velocity and cadence. Motor function decreased significantly (p< 0.05). There was reduced motor power in 18 of the 20 at 6 months.

Discussion: Our results quantified objectively the magnitude of strength changes after multi-level surgery and show that weakness may be greater and persist longer than expected. This information will be useful for planning treatment after multi-level surgery and is part of a randomised trial investigating strength training. In general there is a decrease in power but an improvement in gait.

Introduction: Traditionally, the degree of correction for derotational femoral osteotomies in cerebral palsy has been based on clinical or radiographic measures. Recently, three dimensional gait analysis has been used to plan and evaluate orthopaedic surgery. Our aim was to assess the outcome of derotation osteotomies, where the degree of rotation at surgery was guided by transverse plane kinematics (aiming at reducing peak hip rotations to normal limits).

Method: Pre and post-operative gait analyses were reviewed in a group of these patients (16 legs) and compared with a similar group of 8 patients (16 legs) who had soft tissue procedures only.

Results: Improvement following derotation osteotomy occurred in all but one case; 11/16 osteotomies resulted in peak internal rotation within one standard deviation (SD) of peak normal internal rotation (normal range −6° to +11°), the other 4 were within 1.4 SDs.

Discussion: Objective improvement in hip rotation during gait was measured in 15/16 subjects undergoing dero-tation osteotomy based on gait analysis. There was no rotational change overall in patients who had soft tissue procedures only. Average dynamic correction of internal rotation during gait was slightly less than intra-operative correction, possibly due to tensioning of spastic muscles.