Rupesh Kumar Vaidya1, Cheol Whan Yoo1, Joonhee Lee1, Hyuk-Soo Han1, Myung Chul Lee1, Du Hyun Ro2. 1. Department of Orthopaedic Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. 2. Department of Orthopaedic Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. duhyunro@gmail.com.
Abstract
PURPOSE: The pivot shift (PS) test is commonly used to diagnose and evaluate the dynamic instability of the knee joint in cases of anterior cruciate ligament (ACL) tear. There is a need of a reliable and inexpensive tool which is easily available to measure PS objectively in a clinical setting. The purpose of this study was to evaluate the use of a smartphone, which is readily available, to assess the PS phenomenon. METHODS: Seventeen patients with unilateral ACL-injured knees, undergoing ACL reconstruction, were enrolled in the study. PS was initially graded according to the International Knee Documentation Committee classification by two observers. The PS test was then performed by them in normal and injured knees under anaesthesia using a smartphone attached to Gerdy's tubercle. Acceleration changes during the PS test were recorded using the smartphone accelerometer application. Intra-observer and inter-observer reliability of the test among the two observers were evaluated. Acceleration changes were compared between the injured and normal knees, and also between the clinical grades of PS. Diagnostic utility of the smartphone accelerometer was examined by a receiver operating characteristic curve analysis. RESULTS: Intra-observer and inter-observer reliability were high for the smartphone accelerometer. The acceleration change was higher in the ACL-injured knees than in normal knees. The mean acceleration change was 2.54 m/s2 (SD = 0.97) in ACL-injured knees and 0.73 m/s2 (SD = 0.19) in normal knees (p < 0.001). The mean acceleration change of Grade 1 knees was 1.89 m/s2 (SD = 0.57), and that of knees of Grade 2 and above were 2.99 m/s2 (SD = 0.95) (p < 0.05). Sensitivity was 94% and specificity was 100% for the acceleration change required to detect ACL injury, i.e., 1.24 m/s2. CONCLUSIONS: The results show that a smartphone can be used to evaluate the PS quantitatively and reliably, in the diagnosis of ACL injury. LEVEL OF EVIDENCE: II.
PURPOSE: The pivot shift (PS) test is commonly used to diagnose and evaluate the dynamic instability of the knee joint in cases of anterior cruciate ligament (ACL) tear. There is a need of a reliable and inexpensive tool which is easily available to measure PS objectively in a clinical setting. The purpose of this study was to evaluate the use of a smartphone, which is readily available, to assess the PS phenomenon. METHODS: Seventeen patients with unilateral ACL-injured knees, undergoing ACL reconstruction, were enrolled in the study. PS was initially graded according to the International Knee Documentation Committee classification by two observers. The PS test was then performed by them in normal and injured knees under anaesthesia using a smartphone attached to Gerdy's tubercle. Acceleration changes during the PS test were recorded using the smartphone accelerometer application. Intra-observer and inter-observer reliability of the test among the two observers were evaluated. Acceleration changes were compared between the injured and normal knees, and also between the clinical grades of PS. Diagnostic utility of the smartphone accelerometer was examined by a receiver operating characteristic curve analysis. RESULTS: Intra-observer and inter-observer reliability were high for the smartphone accelerometer. The acceleration change was higher in the ACL-injured knees than in normal knees. The mean acceleration change was 2.54 m/s2 (SD = 0.97) in ACL-injured knees and 0.73 m/s2 (SD = 0.19) in normal knees (p < 0.001). The mean acceleration change of Grade 1 knees was 1.89 m/s2 (SD = 0.57), and that of knees of Grade 2 and above were 2.99 m/s2 (SD = 0.95) (p < 0.05). Sensitivity was 94% and specificity was 100% for the acceleration change required to detect ACL injury, i.e., 1.24 m/s2. CONCLUSIONS: The results show that a smartphone can be used to evaluate the PS quantitatively and reliably, in the diagnosis of ACL injury. LEVEL OF EVIDENCE: II.
Authors: Ji Eui Kim; Dong Hyun Kim; Jae Ik Lee; Han Gyeol Choi; You Sun Jung; Sang Hoon Lee; Yong Seuk Lee Journal: Knee Surg Sports Traumatol Arthrosc Date: 2020-05-27 Impact factor: 4.342
Authors: Richard J Napier; Julian A Feller; Brian M Devitt; Jodie A McClelland; Kate E Webster; Ciaran S J Thrush; Timothy S Whitehead Journal: Orthop J Sports Med Date: 2021-01-22