Virtual reality rehabilitation in patients with total knee replacement: Preliminary results

Abstract

INTRODUCTION
Impaired proprioceptive accuracy could be a risk factor for progression of gait limitations in knee osteoarthritis patients, even after the Total Knee Replacement (TKR) [1]. Recent studies on Virtual Reality (VR) in rehabilitation show its efficacy in restoring proprioceptive capacity, postural control and gait [2]. However, literature lacks such studies in TKR patients. This preliminary study aims to evaluate the efficacy of a VR system for the enhancement of motor skills in TKR patients.

METHODS
10 TKR patients were enrolled within 10 days after an unilateral TKR: 5 (66±10 y.o.) Control Group (CG) and 5 (64±10 y.o.) Virtual Realty Group (VRG). All subjects conducted 15 sessions of fortyfive-minutes (5 times/week) of VR (VRG) or traditional (CG) postural control and proprioceptive exercises. The VRG used the VRRS (Khymeia, Italy) standing on the balance board and receiving a real-time visual bio-feedback in serious video games. Clinical assessments and gait analysis (BTS SMART-DX Motion Capture Systems, Italy) were performed before (T1) and after (T2) rehabilitation period. Wilcoxon’s test (p<0.05) was used to detect significant changes between T1 and T2.

RESULTS
At T1, no significant differences were found between groups. Statistically significant improvements were longitudinally found for both groups in 10mWT, MRC QF, MRC TA, and VAS. Significant variation of TUG was found in VRG only. The gait analysis shows significant variation in the spatio-temporal parameters (mean velocity, cadence, cycle length, prosthetic step length) in the VRG only.

DISCUSSION
The VR system improves motor skills (gait, postural control, and direction shift) in TKR patients compared to traditional therapy. The results obtained with the gait analysis and the TUG test are encouraging and suggest further instrumental investigations on the sit-to-stand and balance tasks. An RCT on a larger sample is currently in progress in order to confirm these preliminary results.

Table 1. Mean values (standard deviation) of clinical and instrumental parameters in both groups. (on request)

REFERENCES
[1] Knoop J, et al. Osteoarthritis and Cartilage 2011;19(4):381-388.
[2] Laver K, et al. Stroke 2012;43(2):20-21.

Full text

Virtual Reality Rehabilitation in Patients with Total Knee Replacement: Preliminary Results
S. Pournajaf
1
, M. Goffredo
1
, S. Criscuolo
1
, M. Galli
2
, C. Damiani
1
, M. Franceschini
1,3
1
Department of Neurorehabilitation IRCCS San Raffaele Pisana, Rome, Italy
2
Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
3
San Raffaele University, Rome, Italy
INTRODUCTION
Impaired proprioceptive accuracy could be a risk factor for progression of gait limitations in knee
osteoarthritis patients, even after the Total Knee Replacement (TKR) [1]. Recent studies on Virtual
Reality (VR) in rehabilitation show its efficacy in restoring proprioceptive capacity, postural control and
gait [2]. However, literature lacks such studies in TKR patients. This preliminary study aims to
evaluate the efficacy of a VR system for the enhancement of motor skills in TKR patients.
METHODS
10 TKR patients were enrolled within 10 days after an unilateral TKR: 5 (66±10 y.o.) Control Group
(CG) and 5 (64±10 y.o.) Virtual Realty Group (VRG). All subjects conducted 15 sessions of fortyfive-
minutes (5 times/week) of VR (VRG) or traditional (CG) postural control and proprioceptive exercises.
The VRG used the VRRS (Khymeia, Italy) standing on the balance board and receiving a real-time
visual bio-feedback in serious video games. Clinical assessments and gait analysis (BTS SMART-DX
Motion Capture Systems, Italy) were performed before (T1) and after (T2) rehabilitation period.
Wilcoxon’s test (p<0.05) was used to detect significant changes between T1 and T2.
RESULTS
At T1, no significant differences were found between groups. Statistically significant improvements
were longitudinally found for both groups in 10mWT, MRC QF, MRC TA and VAS. Significant
variation of TUG was found in VRG only. The gait analysis show significant variation in the spatio-
temporal parameters (mean velocity, cadence, cycle length, prosthetic step length) in the VRG only.
DISCUSSION
The VR system improves motor skills (gait, postural control and direction shift) in TKR patients
compared to traditional therapy. The results obtained with the gait analysis and the TUG test are
encouraging and suggest further instrumental investigations on the sit-to-stand and balance tasks. A
RCT on a larger sample is currently in progress in order to confirm these preliminary results.
Table 1. Mean values (standard deviation) of clinical and instrumental parameters in both groups.
VRG CG
T1 T2 T1 T2
TUG (s) 23.26 (3.19) 12.17 (2.29) 26.80 (10.07) 18.09 (6.11)
10mwt (s) 16.98 (2.35) 10.79 (2.31) 21.02 (1.60) 12.8 (2.53)
MRC QF 3.10 (0.74) 4.30 (0.27) 2.80 (0.44) 4.30 (0.27)
MRC TA 3.30 (0.44) 4.20 (0.27) 2.80 (0.27) 4.20 (0.44)
Clinical Tests
VAS 4.60 ( 1.81) 2.40 (0.89) 6.40 (1.81) 4.00 (1.87)
Mean velocity (m/s)
0.36 (0.08) 0.56 (0.15) 0.38 (0.08) 0.48 (0.14)
Cadence (step/min)
65.06 (11.88) 78.80 (12.97) 69.89 (8.49) 80.04 (8.15)
PS HS PS HS PS HS PS HS
Cycle length (m) 0.64
(0.10) 0.60
(0.19) 0.83
(0.13) 0.82
(0.11) 0.612
(0.08) 0.62
(0.08) 0.73
(0.18) 0.74
(0.18)
Gait parameters
Step length (m) 0.32
(0.04) 0.33
(0.07) 0.42
(0.06) 0.41
(0.06) 0.34
(0.06) 0.28
(0.06) 0.37
(0.09) 0.35
(0.10)
TUG: Timed Up and Go test; 10mwt: 10 metres walking test; MRC QF: Medical Research Council
Quadriceps Femoris scale ; MRC TA: Medical Research Council Tibialis Anterior scale; VAS: Visual
Analog Scale ; PS: prosthetic side; HS: healthy side; bold=p<0.05, T1 vs T2
REFERENCES
[1]
Knoop J, et al. Osteoarthritis and Cartilage 2011;19(4):381-388.
[2] Laver K, et al. Stroke 2012;43(2):20-21.