M. Perrott

Knee biomechanics early after knee replacement surgery predict abnormal gait patterns 12 months postoperatively.

An abnormal flexor moment pattern is often evident following total knee replacement (TKR) surgery. We investigated whether such a pattern at 12 months post‐surgery could be predicted using biomechanical gait measures assessed before surgery and at 4 months post‐surgery. Thirty two TKR patients were evaluated and classified as normal (biphasic pattern) or abnormal (flexor moment pattern) at each time point. Biomechanical parameters collected before surgery and at 4 months post‐surgery were then explored for their ability to predict gait patterns at 12 months post‐surgery. The gait pattern at 4 months was significantly associated with the 12 month post‐surgery gait pattern, with over half of those with a flexor moment pattern at 4 months retaining this pattern at 12 months. Discriminant function analysis indicated that peak knee flexion during early stance, peak knee extension, and peak knee extension moment at 4 months post‐surgery were independent predictors of the gait pattern at 12 months. Thus, an abnormal knee flexor moment pattern at 12 months post‐surgery can be predicted by biomechanical analysis 4 months after surgery. Therefore, interventions aimed at improving active extension may need to be implemented early after surgery to restore a normal gait pattern.

The anatomical basis for clinical tests assessing musculoskeletal function of the shoulder

Abstract A large number of clinical tests have been reported to assess the musculoskeletal integrity of the shoulder; however, for some of these tests, diagnostic accuracy is poor. Poor diagnostic accuracy may be related to a lack of understanding of the anatomical basis of the test. We conducted a systematic review of the relevant literature to ascertain whether an anatomical basis had been established for 34 common clinical tests for shoulder pathology. Searching of electronic databases yielded 11 papers that had reported on the anatomical basis for a total of six of the 34 clinical tests. Four of these tests had evidence from more than one study of a valid anatomical basis, but only two tests provided consensus evidence that supported the anatomical basis provided by the test developer. The lack of evidence about the anatomical validity of common clinical tests for shoulder function may explain the poor diagnostic accuracy of many of these tests. Further research into anatomical validity of tests may assist in the development of clinical tests of musculoskeletal integrity with improved diagnostic accuracy.

Accuracy of clinical tests to diagnose superior labral anterior and posterior (SLAP) lesions

Abstract Numerous clinical tests to diagnose superior labral anterior and posterior (SLAP) lesions of the glenoid labrum have been described. The current systematic review of the relevant literature was undertaken to ascertain the accuracy of these tests as determined by likelihood ratios. Searching of electronic databases yielded 16 papers that had reported test accuracy on a total of 16 separate clinical tests for SLAP lesions, and some combinations of these tests. Although many tests appeared to be highly accurate when initially reported, all tests that had been evaluated by authors other than those who devised the test typically showed poor levels of accuracy in subsequent studies. The results of this review suggest that no one clinical test can be recommended for use in clinical practice to diagnose accurately the presence or absence of a SLAP lesion. It is possible that further investigations into the anatomical basis of these tests may explain the variability in accuracy.

Development of Clinical Rating Criteria for Tests of Lumbopelvic Stability

Background. Lumbopelvic stability (LPS) is regarded as important for injury prevention, yet there are few reliable or valid tests that can be used in the clinical assessment of LPS. Three dynamic functional tests were identified that assess LPS in multiple planes of motion: dip test (DT), single leg squat (SLS), and runner pose test (RPT). Existing rating criteria for SLS have limited reliability and rating criteria for DT and RPT have not been established. Objective. To develop rating criteria for three clinical tests of LPS. Design. Qualitative research: focus group. Method. A focus group of five expert physiotherapists used qualitative methods to develop rating criteria for the three clinical tests. Results. Detailed rating criteria were established for the three tests. Each key factor considered important for LPS had characteristics described that represented both good and poor LPS. Conclusion. This study established rating criteria that may be used to clinically assess LPS.

Lumbopelvic exercise reduces lower limb muscle strain injury in recreational athletes

Abstract Background: Lower limb muscle strain injury (LLMSI) has a high incidence in sport. Reports of injury reduction after lower limb stretching and strengthening interventions have been inconsistent; however, it has been proposed that poor proximal control may predispose athletes to LLMSI. Deficits in lumbopelvic stabilizers, reduced trunk control, pelvic strength imbalance, poor balance and reduced hip flexibility have been reported as risk factors for leg muscle injuries including hamstring, groin and thigh strain. Exercise interventions targeting the lumbopelvic region may be effective in preventing LLMSI. Objective: To determine if lumbopelvic exercise interventions reduce the incidence of LLMSI. Methods: Databases were searched for exercise trials that targeted the lower back, abdomen, pelvis and hip. The search included a range of interventions: lumbopelvic stability, resistance training, muscle stretching and posture or balance exercise. Quality of included trials was assessed using the PEDro scale. Results: Six studies were identified that compared lumbopelvic exercise with other interventions or usual training and reported the incidence of LLMSI. Lumbopelvic exercise intervention was favoured with a significant effect size both in a meta-analysis (OR = 0·40, 95% CI 0·17–0·94, P = 0·03) and in a sensitivity analysis based on one high quality study (OR = 0·27, 95% CI 0·09–0·75, P = 0·01). Sub-group analysis of three balance studies did not show a significant effect in reducing LLMSI. Conclusions: Lumbopelvic exercise reduces the incidence of LLMSI. Stabilization, agility and neuromuscular were the most successful interventions.

Comparison of lower limb and trunk kinematics between markerless and marker-based motion capture systems

Three dimensional (3-D) motion capture systems are used by researchers and clinicians to analyze the kinematics of human movement. Traditional marker based systems are time consuming and limit the size of studies. Markerless 3-D systems are quicker to use but the differences between data captured in each system is unclear. AIM To examine the relationship of kinematic data captured by marker based and markerless motion capture systems. METHODS Movement was assessed in two tests: a simple knee flexion test and single leg squat with a marker based protocol (Vicon) and a markerless protocol (Organic Motion). RESULTS There was no significant difference between protocols in knee flexion angle (p=0.33). In single leg squat there was no significant difference in 9 of 13 clinically relevant joint angles in the change in angle from the start to the peak of squat. There were significant differences in the angle at the peak of the squat for 9 of 13 joint angles. DISCUSSION This study provides evidence that a marker-based and a markerless protocol report similar ranges of change in angle from the start of a squat to peak squat in the pelvis and lower limb in single leg squat. Specific joint angles should not be compared between protocols.