Knee Stability and Movement Coordination Impairments: Knee Ligament Sprain: Clinical Practice Guidelines Linked to the International Classification of Functioning, Disability, and Health from the Orthopaedic Section of the American Physical Therapy Association

. Author manuscript; available in PMC: 2011 Aug 21.

Published in final edited form as: J Orthop Sports Phys Ther. 2010 Apr;40(4):A1–A37. doi: 10.2519/jospt.2010.0303

Laxity With Valgus Stress Test at 30°
ICF category	Measure of impairment of body function, stability of a single joint

Description	The amount of separation between the tibia and femur at the MCL during a valgus stress test performed with the knee in 30° of flexion

Measurement method	The patient is supine. While facing toward the feet of the patient, the examiner holds the ankle of the tested limb with the outside hand. The limb is extended over the edge of the testing table. The examiner places his inside thigh against the thigh of the tested limb. The knee is flexed to 30°. The opposite hand of the examiner is placed over the medial joint line of the tested limb. The examiner applies a valgus force by abducting the ankle and stabilizing the thigh. The amount of separation between the femur and tibia, suggestive of a disruption of the MCL, is recorded.

Nature of variable	Ordinal

Units of measurement	As described by the IKDC 2000 knee examination form⁴, severity is graded as a difference in the involved knee compared to normal or what is assumed to be normal: Normal (−1–2 mm) Nearly normal (3–5 mm) Abnormal (6–10 mm) Severely abnormal (>10 mm)

Measurement properties	Diagnostic Accuracy⁷⁶
			95% CI
	Sensitivity	91%	81%–100%
	Specificity	49%	39%–59%
	Negative likelihood ratio	0.2	0.1–0.6
	Positive likelihood ratio	1.8	1.4–2.2