Abstract: Musculoskeletal dysfunctions such as osteoarthritis and low back pain are commonly seen among transfemoral amputees (TFAs), and are considered as secondary disabilities among amputees. The amputation surgery changes the biomechanics of transfemoral amputees abruptly. It is not unusual that the gait deviation in TFAs is commonly observed and the primary cause is muscle weakness. The amputation leads to the loss of muscle distal insertion sites and the change of muscle’s moment arm, thus the force can be generated by hip muscles is affected. These biomechanical disadvantages result in hyperlordotic posture and load increment at the intact limb. As the consequences, TFAs have a high risk of getting back pain and knee osteoarthritis at
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In the early stage of prosthetic gait training, it is important to re-orientate TFAs to maintain the centre of pressure (COG) between two limbs, then only progress to the displacement of COG side to side and forward-backward. Walking aids can be prescribed to promote a symmetry posture and to improve weight bearing at the prosthetic leg. Lastly, an interdisciplinary approach is important in TFAs prosthetic rehabilitation in reducing or preventing musculoskeletal injuries.Next, hyperlordotic posture is commonly seen in TFAs and it may entail back pain among them. Aforementioned, hip extensor weakness is related to the above knee amputation and iliopsoas remains intact. This explains the presentation of limited hip extension range and hip flexors tightness at amputated side (Gottschalk, 1999). The reduction in iliopsoas muscle length will increase lumbar lordosis as it attaches to vertebral bodies T12 – L5, meanwhile hamstrings are weakened during the amputation and are incapable in hindering pelvic anterior tilt (Gaunaurd et al., …show more content…
The articular cartilage has viscoelastic properties. This unique feature allows articular cartilage to carry out its functions, to absorb the compressive load and transmit it to the subchondral bone (Sophia Fox et al., 2009). Excessive loading on cartilage can damage the extracellular matrix and increase catabolic activity (Sun, 2010). Moreover, bone in the osteoarthritic stage has lower modulus to absorb the forces, and transfer the load back to cartilage (Leng et al., 2013). This vicious cycle will lead to knee osteoarthritis. TFAs commonly have shorter prosthesis stance duration as they are incapable to balance at the amputated leg, feel the stump pressure pain or lack of confidence to transfer weight to the prosthetic leg. They rely on intact limb in walking, climbing stairs and overcoming ramps, soft ground (Kendell et al., 2016). Hence, the load at sound limb is consistently high. As a result, osteoarthritic changes are more pronounce at the intact limb as the cumulative of excessive joint load deforms articular cartilage (Maly, 2008). There is another interesting finding in TFAs population. According to Chang et al, the knee adduction moment of the intact leg was 32% more than the prosthetic side (Diagram 3) (Chang et al., 2011). A larger knee adduction moment means a higher torque trying to rotate the tibia into varus
In the early stage of prosthetic gait training, it is important to re-orientate TFAs to maintain the centre of pressure (COG) between two limbs, then only progress to the displacement of COG side to side and forward-backward. Walking aids can be prescribed to promote a symmetry posture and to improve weight bearing at the prosthetic leg. Lastly, an interdisciplinary approach is important in TFAs prosthetic rehabilitation in reducing or preventing musculoskeletal injuries.Next, hyperlordotic posture is commonly seen in TFAs and it may entail back pain among them. Aforementioned, hip extensor weakness is related to the above knee amputation and iliopsoas remains intact. This explains the presentation of limited hip extension range and hip flexors tightness at amputated side (Gottschalk, 1999). The reduction in iliopsoas muscle length will increase lumbar lordosis as it attaches to vertebral bodies T12 – L5, meanwhile hamstrings are weakened during the amputation and are incapable in hindering pelvic anterior tilt (Gaunaurd et al., …show more content…
The articular cartilage has viscoelastic properties. This unique feature allows articular cartilage to carry out its functions, to absorb the compressive load and transmit it to the subchondral bone (Sophia Fox et al., 2009). Excessive loading on cartilage can damage the extracellular matrix and increase catabolic activity (Sun, 2010). Moreover, bone in the osteoarthritic stage has lower modulus to absorb the forces, and transfer the load back to cartilage (Leng et al., 2013). This vicious cycle will lead to knee osteoarthritis. TFAs commonly have shorter prosthesis stance duration as they are incapable to balance at the amputated leg, feel the stump pressure pain or lack of confidence to transfer weight to the prosthetic leg. They rely on intact limb in walking, climbing stairs and overcoming ramps, soft ground (Kendell et al., 2016). Hence, the load at sound limb is consistently high. As a result, osteoarthritic changes are more pronounce at the intact limb as the cumulative of excessive joint load deforms articular cartilage (Maly, 2008). There is another interesting finding in TFAs population. According to Chang et al, the knee adduction moment of the intact leg was 32% more than the prosthetic side (Diagram 3) (Chang et al., 2011). A larger knee adduction moment means a higher torque trying to rotate the tibia into varus