Evaluation of the reproducibility of the KT-1000 arthrometer

• Published in: Scandinavian journal of medicine & science in sports 2001-04, Vol.11 (2), p.120-125
• Main Authors: Sernert, N., Kartus, J., Köhler, K., Ejerhed, L., Karlsson, J.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Anesthesia; Anterior Cruciate Ligament Injuries; Biological and medical sciences; Humans; Investigative techniques, diagnostic techniques (general aspects); Joint Instability - diagnosis; Joint Instability - physiopathology; Knee Joint - physiopathology; Male; Medical sciences; Middle Aged; Orthopedic Equipment; Osteoarticular system. Muscles; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Range of Motion, Articular - physiology; Reference Values; Reproducibility of Results; Rupture - diagnosis; Statistics, Nonparametric
• ISSN: 0905-7188; 1600-0838
• DOI: 10.1034/j.1600-0838.2001.011002120.x

The aim of the study was to examine whether the KT‐1000 arthrometer was reliable when it came to distinguishing between a group of patients with a chronic anterior cruciate ligament (ACL) rupture and a group of patients without an ACL rupture, and to examine the reproducibility of the examination between two experienced examiners. The aim was also to examine whether the KT‐1000 measurements were dependent on whether the patients were awake or under anaesthesia. The study comprised 40 patients: Group A consisted of 20 patients who had a chronic unilateral ACL rupture and Group B consisted of 20 patients who were scheduled for arthroscopy due to knee problems other than an ACL rupture. The KT‐1000 examination was performed before surgery by two experienced physiotherapists (PT I and PT II). PT II subsequently performed a retest of the patients under anaesthesia. The mean anterior side‐to‐side laxity difference between PT I and PT II was 0.2 mm in Group A and 1.8 mm in Group B (n.s., P=0.03). The anterior side‐to‐side measurements of knee laxity revealed significant differences between Group A and Group B, independent of who the measurements were made by when the patients were awake (PT I P=0.011, PT II P=0.001). However, no significant difference (P=0.063) was found when the patients were under anaesthesia. The interclass correlation coefficient (ICC) between PT I and PT II in Group A was 0.55 (P=0.005) for the anterior side‐to‐side laxity, while it was 0.60 (P=0.002) in Group B. There were no significant differences within Group A or Group B between the measurements made when people were awake compared with those under anaesthesia. The conclusions of the study were that the KT‐1000 arthrometer was able to distinguish a group of patients with an ACL rupture from a group without one. The reproducibility of the KT‐1000 measurements of anterior knee laxity between two experienced examiners was considered as fair. Furthermore, the measurements were not dependent on whether the patients were awake or under anaesthesia.