Sitting Comfort Research Articles

Cushioning capability analysis of seat foundations considering the sitter’s anthropometric dimensions

Sitting comfort is primarily determined by the cushioning capability of the seat foundation. Limited literature has been found related to the effects that different sized human buttocks had on the cushioning capability of the seat foundation. Moreover, there is no testing method specialized to measure the load-deformation behavior of foam cushions that imitates the sitting behavior between indenters with different sizes and seat support. This study investigated the effects of various indenter diameters (20 cm, 30 cm, 36 cm, 41 cm, 51 cm, and 58 cm), foam stiffness levels (high and low), and seat bases (spring versus solid flat panel) on the compressive load-deformation behavior of upholstered seat foundations. The load-deformation curves of all the tested foam-seat base combinations exhibited three typical regions, i.e., linear elasticity, plateau, and densification, when subjected to the loads applied through different indenter diameters. Statistical results indicated that the primary effects of the indenter diameter, foam stiffness level, and seat base had significant effects on the spring constants, which represented the slopes of lines in these three regions. In addition, a regression technique was proposed to derive power equations for the estimation of the spring constants of a seat foundation as a function of the indenter diameter, foam material stiffness, and seat base type.

Bone-anchored prostheses in patients with traumatic bilateral transfemoral amputations: rehabilitation description and outcome in 12 cases treated with the OPRA implant system

Purpose: To describe the rehabilitation experience and outcome of treatment with bone-anchored prostheses in individuals with bilateral transfemoral amputations (TFAs) treated in Sweden over a period of 25 years.Method: Hospital records were reviewed for all patients with traumatic bilateral TFAs treated until 2015. The use of prostheses, walking aids and wheelchairs was noted.Results: The cohort comprised 12 patients (nine men and three women with a mean age 35 years at treatment) and the median follow-up time was seven years (1–20). At baseline, 9/12 used prostheses and 3/12 did not. The main means of locomotion was in a wheelchair without wearing prostheses (n = 8/12) or in a wheelchair in combination with prosthetic walking supported by walking aids (n = 4/12). All prosthetic users had problems with sitting comfort. At follow-up, 11/12 patients used prostheses, while one did not. The means of locomotion was prosthetic walking in 3/12 cases, a combination of a wheelchair and prosthetic walking in 4/12, a wheelchair while wearing prostheses but not walking in 4/12 and a wheelchair without wearing prostheses in 1/12. Three patients walked unsupported by walking aids. Seven patients had no problem with prosthetic sitting comfort (n = 3 had small problems).Conclusions: Bone-anchored prostheses in patients with bilateral TFAs resulted in more prosthesis use during everyday locomotion, due hypothetically to improved comfort while wearing prostheses. The results further underline the importance of other assistive devices such as wheelchairs and walking aids used in combination with prostheses in this group of patients facing severe functional limitations.Implications for RehabilitationThis study provides an insight into the details of the rehabilitation and outcome in patients with traumatic bilateral transfemoral amputations treated with bone-anchored prostheses in Sweden.The treatment can lead to a large amount of prosthetic use, but most patients will also use a range of assistive devices including full-length prostheses, stubbies, walking aids and wheelchairs after treatment.The importance of sitting in comfort while wearing prostheses should not be underestimated in patients with bilateral transfemoral amputations.

2410 自動車シートの座り心地に及ぼす座面角の影響(OS.4 感性・快適性・バリアフリー)

2410 自動車シートの座り心地に及ぼす座面角の影響(OS.4 感性・快適性・バリアフリー)