**2.1 Gait phases**

The constant and characteristic gait feature includes its cyclicity, i.e. the alternating occurrence of two phases (Bober, 1985):


Gait Analysis in Patients with Gonarthrosis Treated by Total Knee Arthroplasty (TKA) 49




While describing gait periods attention should also be paid to the changing range of motion







This is the end of the support phase.

leg is at the level of the support foot);

and ends when the heel touches the ground;

in the individual lower extremity joints (Fig. 2):

until the forefoot is placed on the ground;


Fig. 2. Angular placing of joints during gait cycle (Perry, 1992).


position);

foot;

20º;

foot;

position (Fig. 2)

lateral and medial ankles are lifted and it ends when the other foot touches the ground.

pre swing mid swing terminal swing

**General division Detailed division Indirect positions**  support shock-absorption rebound initial contact mid stance toe off

pre swing

terminal swing

In each gait cycle the alternating phases of lower extremity movements listed in Table 1 can be distinguished.

swing

The first application of gait analysis for clinical needs was described at Rancho Los Amigos Medical Center in Los Angeles. Dr Jacqueline Perry used film cameras and a dynamometric platform to determine the gait stereotype in children with lower extremity orthopedic problems, such as the monitoring of surgical treatment results (Minns 2004). It was also there that a gait division system commonly used today was devised (Fig. 1) (Perry, 1992).

Fig. 1. Gait phases worked out by Rancho Los Amigos Medical Center (Perry, 1992)

On the basis of this division, the gait cycle is divided into the support phase and the swing phase. The support phase consists of:


lateral and medial ankles are lifted and it ends when the other foot touches the ground. This is the end of the support phase.


48 Recent Advances in Arthroplasty

In each gait cycle the alternating phases of lower extremity movements listed in Table 1 can

The first application of gait analysis for clinical needs was described at Rancho Los Amigos Medical Center in Los Angeles. Dr Jacqueline Perry used film cameras and a dynamometric platform to determine the gait stereotype in children with lower extremity orthopedic problems, such as the monitoring of surgical treatment results (Minns 2004). It was also there that a gait division system commonly used today was devised (Fig. 1) (Perry, 1992).

initial contact mid stance toe off

pre swing mid swing terminal swing

**General division Detailed division Indirect positions** 

shock-absorption

rebound

pre swing

terminal swing

Fig. 1. Gait phases worked out by Rancho Los Amigos Medical Center (Perry, 1992)

other leg is lifted up and enters the limb advancement period;

On the basis of this division, the gait cycle is divided into the support phase and the swing



be distinguished.

support

swing

Table 1. Step phases (Bober, 1985)

phase. The support phase consists of:


While describing gait periods attention should also be paid to the changing range of motion in the individual lower extremity joints (Fig. 2):


Fig. 2. Angular placing of joints during gait cycle (Perry, 1992).

Gait Analysis in Patients with Gonarthrosis Treated by Total Knee Arthroplasty (TKA) 51

of points and registers their changes in space. The so-called passive markers are glued directly on the patient's skin. Their arrangement reflects the pattern of the biomechanical model. They are glued along the joint axes at an appropriate distance from the centre of the joints and at characteristic points on the head, chest and pelvis. In this way, it is possible to create a spatial representation of these segments of the body and to measure the individual

It is important to place the markers of the head, trunk and the lower half of the body in a precise manner. Anterior head markers define the beginning and the scale of the head as a body part, and the posterior markers indicate its location in space. Trunk markers (C7, CLAV, TH10, STRN), together with head markers, determine the axes of the coordinate system of the trunk. The pelvic markers (LASI, RASI), together with the sacrum marker, define the axes of the coordinate system of the pelvis. The marker of the sacrum should be placed in the plane perpendicular to the line joining the ASIS markers (LASI i RASI). It is very important to place the knee markers and the thigh and crus markers in the proper

The Microsoft Excel software and the statistical package SPSS 14 were used for statistical analysis of the research results. The statistical analysis of the data collected was performed

Descriptive methods of statistics were used to present the results in tables containing

Mathematical methods of statistics involved significance analysis of the means for repeated

Both of the aforementioned techniques assumed that the dependent variable distribution is not distant from normal. However, the legitimacy of this assumption cannot be verified using such a small sample. Therefore, it was decided to use parametric tests as the application of non-parametric tests (which do not require a normal distribution) would additionally reduce the strength of the analysis and, in this way, also the chance of obtaining

The values of the range of angular changes in the knee are presented in figures 3-7 in three planes of motion (saggital, frontal and transverse), in patients before and after knee arthroplasty. The grey ribbon in each diagram shows the variability of the results in the healthy population (the mean + 2sd). In the saggital plane, both in the operated and unoperated leg, a limitation of the knee extension at the stance phase is distinctly marked in the 1st and 2nd examination, while insufficient flexion can be noticed at the swing phase.

parameters – the dimensions of the pelvis and the span of the chest.

on the basis of descriptive and mathematical methods of statistics.

arithmetic means, standard deviations (s) and the range (min-max).

measurements by means of Student's t-test for repeated measures.

**4.1 Comparsion of angular changes in knee joint in sagittal plane** 

I bad op – examination before arthroplasty, operated knee I bad n/op – examination before arthroplasty, not operated knee

II bad op – examination after arthroplasty, operated knee II bad n/op – examination after arthroplasty, not operated knee

Angle (degrees) – angular degrees in the knee joint (in degrees)

Normalised (percent) – normalised time of the gait cycle (in percentages)

Norm – angular changes during normal gait in the comparative group (mean value±SD)

manner.

statistically significant results.

Ext – extension, Flex – flexion

**4. Results** 

(Fig. 3)
