Journal of NeuroEngineering and Rehabilitation

as a percent of predicted VO 2max calculated using the method described by Hansen et al. [ 16 , 17 ] or as reported in the respective articles. Percent VO 2max was calculated post hoc in one study [ 4 ] in relation to the results of the age-matched, able-bodied controls completing the same protocol. Weighted means are given in Table 1 . Available data were synthesized into EESs and assigned research grades based on the guidelines estab- lished in the UK-NSF document [ 14 ] . Statements had to be supported by at least two articles to be synthe- sized. The review ’ s six synthesized statements are in- cluded in Table 3 . All empirical evidence statements were supported by Grade A evidence. EES 6 was also designated the grade of E2 indicating synthesis by professional expert opinion. The CPG developed from the findings of this review is outlined in the discussion and is presented in illustrated form in Fig. 3 . The CPG depicts a pathway whereby a patient with limb loss suspected of cardiovascular com- promise may benefit from results of exercise testing to clarify the extent of their conditioning or their candidacy for prosthetic ambulation. It is intended only for use when there is reasonable concern of cardiopulmonary compromise or impairment in a patient which would limit prosthetic use or function. The organization and synthesis of statements into the CPG were based on the expert opinion of the multidisciplinary team. Discussion A systematic literature review regarding exercise testing in the population of individuals with history of lower ex- tremity amputation was performed and articles were evaluated using the UK-NSF critical appraisal tool. This review served as the basis for development of CPG for the use of exercise testing in evaluation of prosthetic candidacy for those individuals with limb loss who are suspected to have cardiovascular compromise. Guide- lines may prove useful when an individual with LEA pre- sents for an initial of prosthetic fitting as well as a subsequent prosthesis. The CPG should not be applied to any case where reasonable concern for cardiopulmo- nary impairment or compromise are not present. All CPGs must also be based in evidence and efficient. There- fore, the aforementioned endpoints will be connected using highly-graded synthesized evidence statements sup- plemented with expert opinion from a consensus of the multi-disciplinary team only when necessary. Although all synthesized EESs received the highest re- search grade provided by the framework, the use of SLE and %VO 2max calculation as an evaluation for cardiorespi- ratory fitness in subjects with LEA had the greatest num- ber of evidentiary support articles. Viability of the SLE test was made by Chin et al. in 1997 [ 3 ] and since most of these articles were produced from the same group, the method for VO 2max prediction is the same between studies and is also commonly used [ 4 – 6 , 16 , 18 , 19 ] . Two defini- tive statements can be made regarding correlation to suc- cessful prosthetic ambulation using this test. The first is that a subject ’ s ability to sustain ≥ 50%VO 2max is likely an indicator for successful prosthetic ambulation in the eld- erly subject with LEA proximal to the knee. Although the definition of elderly varies among the studies in this review many articles have found prosthetic function to decrease with age and, conversely, to increase with youth [ 2 , 10 , 20 ] . For this reason, it can be assumed, at least for the pur- poses of this synthesis, that achievement of a %VO 2max value or workload sustained by an elderly individual which would predict prosthetic ambulatory success would also indicate the likelihood of prosthetic ambulatory success to be achieved in younger subjects. Similarly, energy Table 3 Empirical Evidence Statements (EES) Supporting Articles The single-leg continuous maximal cycle ergometer test propelled by a sound limb is viable for evaluation of cardiorespiratory fitness using the percent achieved of a predicted VO 2max value (%VO 2max ) measured using direct spirometry in subjects with unilateral lower extremity limb loss. 3,4,5,6,19 The ability to sustain an exercise intensity of ≥ 50%VO 2max during a continuous maximal cycle ergometer test propelled by a single, sound limb is a strong predictor of the ability of the elderly subject with lower extremity limb loss proximal to the knee to successfully ambulate 100 m with a prosthesis. 5,6,19 The ability to sustain an exercise intensity of ≥ 60%VO 2max during a continuous maximal cycle ergometer test propelled by a single, sound limb is a predictor of the ability of an elderly, non-vascular subject with unilateral hip disarticulation to ambulate with a prosthesis. 3,5,19 The upper extremity intermittent submaximal cycle ergometer test is viable for evaluation of physical performance using achieved maximum workload (in W) of elderly subjects with lower extremity limb loss. 2,20,26 Achievement of 30 W on a submaximal intermittent upper extremity cycle ergometer test is a strong indicator of the ability of the elderly subject with history of transfemoral limb loss secondary to vascular etiology to successfully ambulate with a prosthesis. 2,15,20 Subjects with history of lower extremity amputation who do not achieve recommended levels of cardiorespiratory fitness or physical function in pre-prosthetic exercise testing should be prescribed a supervised physical rehabilitation program, preferably including ergometry with the sound lower extremity, and re-evaluated upon its completion. (E2) 6,20,26 Klenow et al. Journal of NeuroEngineering and Rehabilitation 2018, 15 (Suppl 1):64 Page 16 of 72