Six studies (n=259) were included: 1 prospective study (n=20), 2 retrospective studies (n=70) and 3 case series (n=169). The sample size ranged from 20 to 83.
Most of the studies included a sub-population from a larger group, but the methods used to select the participants were not clear.
Walking function: 5 studies reported improvements in various measures of walking function with the silicon liner compared with other types of prosthesis. The measures included walking ability indoors and on uneven surfaces, walking speed and distance, use of walking aids, general walking, and ascending and descending stairs and inclines.
Comfort: 3 studies found that between 7% and 53% of patients reported an increase in comfort; one of these studies also reported a decrease in comfort in some patients.
Skin: 3 studies assessed skin changes associated with silicon liner use. These reported increased skin problems from perspiration in 42% after liner use, creasing in the back of knee in 38%, and a decrease in local pressure points (1 study); a decrease in skin abrasion and irritation in some patients, but an increase in ulceration, itching, perspiration, blistering and irritation at the back of knees in other patients (1 study); and a general decrease in skin problems (1 study).
Pain: 3 studies assessed pain. These reported a decrease in stump pain in some patients (1 study), a decrease in phantom limb pain in 19% (1 study), and a decrease in pain sensation in 53% (1 study).
Suspension: 4 studies assessed suspension. One study that clinically examined the pistoning of prosthesis reported less pistoning (by 1.2 cm) with the silicon liner compared with the patellar tendon bearing socket. The other 3 studies did not assess pistoning clinically; they reported varying percentages of patients with improved suspension, with improvement noted in between 15% and 96% of patients.
Cosmesis: the authors stated that patients generally reported improvements in cosmesis. The studies reported improved appearance (1 study), no improvement (1 study), improvement in 63% of patients but decreased cosmesis in other patients (1 study), and improvement in a number of patients (1 study).
Donning and doffing: some studies reported problems with doffing and donning. Two studies reported a decrease in the ease of doffing and donning in 35% and 22% of patients, respectively, but both studies reported improvements in 31% of patients compared with other types of socket. One study reported improvements in some patients but decreases in others. One study reported a significant improvement when using silicon liners.