Physical activity considerations in lower limb amputees

• Reasons for amputation:

  • atherosclerotic cardiovascular disease
  • complication of diabetes mellitus
  • trauma
  • malignancies
  • comorbidities are usually present in the elderly amputee for example:
  • hypertension
  • diabetes
  • peripheral neuropathy
  • reduced vision
  • peripheral vascular disease in the intact limb
  • deconditioned
• Physical activity guidelines in lower limb amputees:

  • 120 to 180 minutes of PA at moderate to vigorous intensity
  • plus 2 sets of challenging strength and balance exercises twice per week
  • health benefits can also be gained during lower intensities and duration
• Prevalence of PA in people living with disabilities:

  • in england, disabled people are twice as likely to be inactive whem compared to non-disabled people
  • 18% of disabled adults engage in at least one physical activity session per week compared to 41% of non-disabled adults
  • moreover "inactive" disabled people with 3+ impairments are more likely not to engage in any form of PA when compared to those with 1 or 2 impairments
• PA levels in adults with a lower limb amputation:

  • in a study with:
  • 72 participants
  • average age of 53.6 years
  • average time of 10.8 years since lower limb amputation
  • 65% male
  • 60% had transtibial amputations
  • the most common causes of amputation was trauma and dysvascular reasons
  • 97% were prosthetic users and 70% had completed outpatient rehabilitation
  • results:
  • majority (61%) of individuals with lower limb amputations did not undertake sufficient amounts of PA to be classified as sufficiently active
• Acute effects on the exercise response:

  • the major impact of amputation on the exercise response is that the bodys asymmetry makes activities much less efficient
  • general cardiovascular demand are 18% to 100% higher
  • aerobic economy is lower than non-amputees
  • peak vo2 is lower than non-amputees
  • perceived exertion and heart rate responses are higher than non-amputees at similar work rates
• Energy expenditure during ambulation with different levels of lower limb amputation

  
• Peak o2 consumption in older adults with a lower limb amputation

  • subjects who underwent amputation had a 13.1% lower aerobic capacity compared with able bodied controls
  • subjects with a vascular amputation had a lower VO2 peak of 29.1% compared with able bodied controls
• Metabolic costs of walking

  
• Plausible explanation for increased metabolic costs

  • vascular amputation are often associated with a greater metabolic cost than traumatic amputations, even when the level of amputation is the same
  • elevated metabolic costs of walking may be related to the number, type and magnitude of compensations to control balance and propulsion
  • for example transfemoral amputees lack mechanical and biological ankle push-off power and compensate by increasing mechanical work at the hip to continue forward progression
  • increased demand is often place on hip and pelvic musculature to control prosthetic knee and intact hip stability
  • these muscles (glutes) are larger and less efficient for propulsion
  • other deviations include vaulting, hip hiking and circumduction and trunk lean, all of which must be controlled by the trunk musculature
• Benefits of aerobic training in amputees

  • improves ventilatory response to exercise and the ventilatory threshold
  • increased maximal oxygen consumption (mean of 20%)
  • improved psychosocial wellbeing and self-efficacy
  • improved insulin sensitivity and reduced risk of prediabetes or diabetes
  • decrease in metabolic costs during ambulation
  • decreased blood platelet adhesiveness fibrinogen and blood viscosity and increased fibrinolysis
  • increased vagal tone and decreased adrenergic activity, resulting in improved heart rate variability
• Benefits of resistance training in amputees

  • reduced muscle atrophy in the amputated and intact limbs
  • increased balance and stability in the intact limb
  • increased hip flexor strength in the amputated limb will enable ground clearance of the prothesis during the swing phase of gait cycle
  • increased upper body strength will enable self-care activities, walking with crutches, transfers and self-propelling in a wheelchair
• Benefits of flexibility training in amputees

  • after prosthesis flexibility training will reduce the risk of developing hip and knee contractures
  • increase gastrocnemius and soleus ROM of the intact limb to reduce the loss of dorsiflexion
  • loss of available can cause problems for the patient who has vascular disease and peripheral neuropathy as increase stress is placed on the plantar structures
• Aerobic training considerations

  • exercise intensity arm vs leg training - heart rate training zones should be set 10 bpm lower during arm ergometers when compared to leg ergometers
  • high impact activities and activities causing friction on the stump should be avoided
  • due to falls risk, the treadmill should be avoided in the early stages on rehab and can be incorporated once the amputee can maintain a self-selected walking speed
  • shorter bouts of aerobic exercise will be more achievable in deconditioned individuals (5 to 10 minute bouts)
  • each programme should be developed specifically for each individual
  • consider the knee locking mechanism for through knee and above knee prothesis
• Strength training consideration

  • use both open chain and closed chain exercise (adapting open chained in closed chain)
  • continue with PIRPAG strengthening exercises
  • the lower extremity regimen should include exercises for the surrounding hip muscles, with particular attention to the hip abductor and hip extensor groups for pelvic stabilisation
  • shoulder stabilisers, adductors and depressors, elbow extensors, wrist stabilisers, and hand grasp strength are of prime importance for supporting the body for transfers and the use of walking aids
• Exercise training considerations:

  • think of 5 cardiovascular exercises and 5 resistance exercises (free active movements)
  • think about how you would adapt the exercise (seated/standing supported)
  • think about how long (time) you would spend on each exercise in the context of a circuit exercise class
  • think about how you would progress or regress the exercises
• Aerobic FITT for LL Amputees

  • Frequency: 3 - 7 days per week
  • Intensity:
  • moderate - 40 to 59% HRR or 11 to 12 RPE
  • intensity - 60 to 89% HRR or 14 to 17 RPE
  • cardiac - 40 to 70% HRR or 11 to 14 RPE
  • Time: 120 - 180 minutes per week of moderate of vigorous intensity PA
  • Type: prolonged, rhythmic activities using large muscle group activities, treadmill, bike, rowing, arm ergometer, swimming

  
• Strength FITT for LL Amputees

  • Frequency: minimum of 2 non-consecutive days per week, preferably 3 days per week
  • Intensity: moderate to vigorous (60 to 80% of 1RM)
  • at least 8 to 10 exercises with 2 to 4 sets of 8 to 12 repetitions
  • Types: resistance machines, bands, free weights, partial/full bodyweight

  
• Flexibility FITT for LL Amputees

  • Frequency: 2 to 3 days per week
  • Intensity: stretch to the point of tightness or slight discomfort
  • Time: hold static stretch for 10 to 30 seconds, 2 to 4 repetitions of each exercise, achieving a total time of 60 seconds for each stretch
  • Type: static, dynamic and/or PNF stretching