[Outcome assessment in total knee arthroplasty: is the clinical measurement of range of motion a reliable measurable outcome variable?]. / Outcome-Messung in der Knieendoprothetik: Ist die klinische Bestimmung der Gelenkbeweglichkeit eine zuverlässig messbare Ergebnisgrösse?

AIM: The aim of this clinical study was to investigate the reliability of the clinical assessment (visual and goniometric) of the range of motion of the knee joint. METHOD: 30 patients were assessed concerning the range of motion of their knee joints by visual and goniometric measurements. Assessment was performed by three investigators. The obtained data were used to analyse the intra- and interobserver reliability. Statistical analysis was performed using the Spearman coefficient of correlation [r (s)]. RESULTS: Intraobserver agreement was consistent across observers regarding the visual and goniometric assessment of flexion (r (s) > 0.6), whereas reliability was uniformly low for both measurements regarding the assessment of extension (r (s) < 0.6). Interobserver agreement was consistent across all three goniometric and two out of three visual assessments regarding the measurement of flexion (r (s) > 0.6); the interobserver reproducibility of extension, however, was uniformly low both for the visual and goniometric measurements (r (s) < 0.6). CONCLUSION: Reliability of clinical assessment of range of motion should be taken critically into consideration whilst performing classical function-related scoring systems when measuring outcome after total joint arthroplasty, since these scoring systems are strongly based on a valid and reliable assessment of range of motion.

[Reliability of transcutaneous measurement of oxygen tension on the lower leg]. / Reliabilität der transkutanen Sauerstoffpartialdruckmessung an der unteren Extremität.

AIM: Measurement of transcutaneous oxygen tension is increasingly used to determine the appropriate level of amputation in patients with vascular disease. The purpose of the present study was to analyze the intra- and interrater reliability of transcutaneous oxygen [tcpO (2)] measurements in a homogeneous study group. METHOD: Five investigators assessed the transcutaneous oxygen tension of both lower legs of seven persons in a fixed setting. Assessment was repeated with the same examiners and the same examinees after 24 hours. TcpO (2) was measured at the posterior aspect of the lower leg twenty centimeters below the knee joint line. The TCM 400 Monitoring System (Radiometer Medical AIS, Bronshoj, Denmark) was used. Statistical analysis of the intra- and interrater reliability was performed with the Spearman coefficient of correlation. RESULTS: An overall mean of 56.2 +/- 10.6 mmHg was found. For the first examination, a mean of 55.3 +/- 10.6 mmHg was observed, whereas for the second examination it was 57.0 +/- 10.5 mmHg. Analysis of intrarater reliability showed a coefficient of correlation of r (s) = 0.56 (p < 0.0001). For interrater reliability, we found coefficients of correlation ranging from r (s) = 0.20 (p = 0.20) to r (s) = 0.69 (p = 0.0004). CONCLUSION: Analysis of transcutaneous oxygen tension measurements performed by different investigators in a fixed setting revealed a non- homogeneous intra- and interrater reliability, which should be taken into account prior to initiating therapy.