The evaluation of rotational lateral ankle laxity in gravity stress position by ultrasonography: normative value in uninjured ankles

• Published in: BMC musculoskeletal disorders Vol. 25; no. 1; pp. 764 - 7
• Main Authors: Yokoe, Takuji, Yang, Fan, Tajima, Takuya, Chosa, Etsuo
• Format: Journal Article
• Language: English
• Published: London BioMed Central 01.10.2024; BioMed Central Ltd; BMC
• Subjects: Adult; Ankle; Ankle Joint - diagnostic imaging; Diagnosis; Diagnosis, Ultrasonic; Epidemiology; Female; Gender; Gravitation; Gravity; Health aspects; Healthy Volunteers; Humans; Hypermobility; Injuries; Internal Medicine; Internal rotation; Joint Instability - diagnostic imaging; Joint Instability - physiopathology; Joints; Lateral Ligament, Ankle - diagnostic imaging; Magnetic resonance imaging; Male; Mechanical properties; Medical examination; Medical research; Medicine; Medicine & Public Health; Medicine, Experimental; Methods; Orthopedics; Patients; Physiological aspects; Prospective Studies; Range of Motion, Articular - physiology; Reference Values; Rehabilitation; Rheumatology; Rotation; Rotation (Joints); Rotational lateral ankle laxity; Sports Medicine; Stress (Physiology); Surgeons; Surgery; Talus; Ultrasonic imaging; Ultrasonography; Ultrasonography - methods; Ultrasound imaging; Young Adult; Young adults; Japan; United States > US; Talus; Internal rotation; Diagnosis; Rotational lateral ankle laxity; Ultrasonography
• ISSN: 1471-2474; 1471-2474
• DOI: 10.1186/s12891-024-07881-5

Background The evaluation of lateral ankle laxity remains challenging when diagnosing chronic lateral ankle instability (CLAI). Several studies have reported that internal rotation of the talus as an indicator of rotational lateral ankle laxity (RLAL) increases in patients with CLAI. However, there is no established method for detecting and evaluating the RLAL. This study aimed to report a novel method for evaluating the RLAL in the gravity stress position by measuring the talofibular distance (TFD) using ultrasonography (US) and show the normative value of the TFD. Methods The TFDs in the subjects with healthy ankles were prospectively measured 10 mm distal to the ankle joint in the neutral ankle position and gravity stress position using US. The differences in the TFD between the two ankle positions were evaluated. The differences in the TFD by gender and ankle laterality were also evaluated. Results A total of 52 healthy ankles of 28 subjects (mean age, 24.0 ± 1.6; male/female, 12/16) were finally included. There was a significant difference in the TFD between the neutral ankle position (6.9 ± 0.9 mm) and gravity stress position (9.0 ± 0.9 mm) ( p  < 0.001). The mean difference in the TFD between the two ankle positions was 2.1 ± 0.6 mm. There were no significant differences in the TFD by gender and ankle laterality. Conclusions The present study reported a novel US method for evaluating RLAL by applying gravity stress and the normative value of the TFD.