Background and Aim: Genu varum and genu valgum are two most common deformities of the knee joint in children and adults. In these deformities knee muscles function maybe affected by the alteration in mechanical axis of lower limb. The aim of this survey was to provide some basic knowledge about the function of knee muscles in patients with genu varum and genu valgum deformities.

Materials and Methods: Studies were identified by searching in the Pub-Med, Science Direct, Google Scholar databases and authoritative references available on the internet and library for articles and books published after 1990,with the key words such as genu varum, genu valgum, knee muscles, bow leg, knock knee and knee frontal angle.

Results: Among 102 papers and 10 books resulted from the first search, only 30 papers and 5 books were related to this literature review and just10 papers and 2 books among them were about changes in knee muscles.

Conclusion: The results of this survey indicated that patients with genu varum and genu valgum deformities have architectural and functional alteration in their knee muscles. According to the results most of these studies have noticed the basic changes in quadriceps muscle function and architecture. It is necessary to study more about the function of other knee muscles.

Key words: Genu varum, Genu valgum, Bow leg, Knock knee, Knee muscles.

Background and Aim: Reliability or unreliability of the results achieved from recording of surface electromyography of muscles has always been questioned. The aim of present study was to  measure the reliability of the delayed reaction time of muscle electromyography of the knee joints on the exposure of unexpected rotary turbulence in the transverse plane from the area of supporting surface.

Materials and Methods: Twenty healthy women from 19 to 30 years old and free from any clear deformities in the lower extremities were participated in the present study. Surface electromyography of the six knee musculature was carried out for every subject separately in 4 situations including: External Rotation (Ext Rot) from plantar area on the transverse plane with bent and straight knee, Internal Rotation (Int. Rot) with the same conditions, Single Leg Stance situation in 4 stages, and repeatability of Intra Session through intra-class correlation coefficients when the muscles are in action on the exposure of turbulence in four applied forms were analyzed.

Result: The results from 24 analyzed forms showed that 18 forms of muscles at the time of action had moderate to high repeatability (Monroe Classification)

Conclusion: Regarding reliability, the muscles indicated different amounts in onset latency time, on the exposure of rotary turbulence, according to joint angle and the direction of applying rotation on the transverse plane. In respect to direction of rotation, most of the muscles indicated more reliability on the exposure of external rotation turbulence (clockwise) in relation to internal rotation (anti-clockwise) and also regarding the joint angle in turbulences with straight knee in relation to turbulences with bent knee. 

Keyword: Knee muscles, Surface electromyography, Reliability, Rotational turbulence