TABLE 2.

Association between impaired muscle strength/function and PAD

Reference	Patients population	Number of patients/controls	Assessment method			Main results
			Muscle strength	Muscle mass/quality	Physical performance
Kakihana et al., 2017, J Vasc Surg 35	PAD	16/10	‐	‐	7‐m walkway embedded with a force plate test	PAD was associated with slower walk at self‐selected walking speed (88.32 ± 15.15 cm/s for PAD patients vs. 126.04 ± 16.31 cm/s for controls, P < 0.001) and at fast walking speed (119.90 ± 21.07 cm/s vs. 162.01 ± 21.47 cm/s for controls, P < 0.001); lower cadence at self‐selected walking speed (109.92 ± 12.17 step/min vs. 118.38 ± 7.28 steps/min, P < 0.001) and at fast walking speed (121.29 ± 11.39 steps/min vs. 135.11 ± 9.47 step/min, P < 0.001); and reduced peak hip flexor generation power at self‐selected walking speed (0.50 ± 0.18 W/kg vs. 1.00 ± 0.22 W/kg, P < 0.001) and at fast walking speed (0.78 ± 0.27 W/kg vs. 1.40 ± 0.39 W/kg, P < 0.001)
Schieber et al., 2017, J Vasc Surg 29	PAD	94/16	Maximal isometric plantar flexion contractions of 10 s	‐	‐	PAD patients exhibited strength deficits, with impaired peak torque values (69.1 ± 28.7 N.m for claudicating patients vs. 98.2 ± 27.6 N.m for controls, P < 0.01)
Dziubek et al., 2015, Maturitas 33	CLI	85/50	Force‐velocity parameters (peak torque, total work, average power) of the lower limb	‐	6‐min walk test	PAD was associated with lower 6‐min walk distance (349.77 ± 65.08 m for PAD patients vs. 515.86 ± 96.39 for controls, P < 0.0001), lower mean walk speed (3.49 ± 0.65 km/h vs. 5.15 ± 0.96 km/h for controls, P < 0.01), and significantly lower values of force‐velocity parameters (including peak torque, total work and average power of the knee joint) compared with the control group (P < 0.005)
Parmenter et al., 2013, J Vasc Surg 34	PAD	22/−	Maximum strength/endurance testing (hip extensors, hip abductors, quadriceps, hamstrings, plantar flexors, pectoral, upper back muscles)	‐	6‐min walk test	Greater severity of PAD was associated with reduced bilateral hip extensor strength (r = 0.54, P = 0.007), whole body strength (r = 0.32, P = 0.05), shorter distance to first stop during the 6‐min walk test (r = 0.38, P = 0.05) and poorer single leg balance (r = 0.44, P = 0.03) (using univariate and stepwise multiple regression models)
Câmara et al., 2012, Ann Vasc Surg 30	PAD	20/9	Plantar flexion/dorsiflexion movements, knee extension/flexion movements	‐	Plantar flexion/dorsiflexion movements, knee extension/flexion movements	PAD patients presented lower muscle strength in dorsiflexion (0.20 ± 0.10 N/m/kg for PAD patients vs. 0.29 ± 0.10 N/m/kg for controls, P < 0.01), plantar flexion (0.36 ± 0.20 N/m/kg vs. 0.53 ± 0.20 N/m/kg, P < 0.01) and knee flexion movements (0.50 ± 0.30 N/m/kg vs. 0.62 ± 0.10, P = 0.04). Also, PAD was associated with lower muscle endurance in dorsiflexion (8.0 ± 3.5 N/m/kg vs. 9.9 ± 6.6 N/m/kg, P = 0.01) and plantar flexion movements (20.0 ± 9.0 N/m/kg vs. 25.7 ± 10.7 N/m/kg, P = 0.02)
Wurdeman et al., 2012, Gait Posture 31	PAD	30/32	Joint moments and powers at early, mid and late stance (hip and knee and ankle joints)	‐	‐	PAD was associated with reduced peak hip power absorption in midstance (−0.788 ± 0.25 W/kg for PAD patients vs.−0.950 ± 0.27 W/kg for controls, P = 0.017), reduced peak knee power absorption in late stance (−0.729 ± 0.21 W/kg vs.−0.899 ± 0.33 W/kg for controls, P = 0.02), and reduced peak ankle power generation in late stance (2.677 ± 0.45 W/kg vs. 2.998 ± 0.60 W/kg, P = 0.021)
Koutakis et al., 2010, J Vasc Surg 32	PAD	20/16	Joint torques and powers at early, mid and late stance (hip, knee and ankle joints)	‐	Ambulation on a walkway	PAD patients presented significantly reduced hip power generation in late stance (0.569 ± 0.18 W/kg for claudicating patients vs. 0.706 ± 0.24 W/kg for controls, P = 0.03), knee power absorption in late stance (−0.580 ± 0.25 W/kg vs. −0.882 ± 0.32 W/kg, P = 0.0015), and ankle power generation in late stance (2.178 ± 0.51 W/kg vs. 2.957 ± 0.69 W/kg, P = 0.0001) Also, PAD was associated with reduced gait velocity (1.09 ± 0.13 m/s for claudicating patients vs. 1.28 ± 0.13 m/s for controls, P = 0.0007) and stride length (1.27 ± 0.11 m vs. 1.47 ± 0.11 m for controls, P < 0.001)
Koutakis et al., 2010, J Vasc Surg 36	PAD	20/10	Joint torques and powers at early, mid and late stance (hip, knee and ankle joints)	‐	‐	PAD was associated with reduced knee power generation in early stance (0.26 ± 0.31 W/kg for claudicating patients vs. 0.62 ± 0.25 W/kg for controls, P < 0.05) and ankle power generation in late stance (2.05 ± 0.59 W/kg vs. 4.00 ± 0.88 W/kg for controls, P < 0.05)
Herman et al., 2009, J Am Geriatr Soc 37	PAD	374/−	Hip extension/flexion, knee extension/flexion strength Walking over a force platform	‐	7‐m walking speed test 6‐min walk test Short physical performance battery	In women with PAD, weaker baseline hip and knee flexion strength were associated with faster average annual decline in usual‐paced 4‐m walking velocity (P trend < 0.001 and P trend = 0.02 respectively) and in short physical performance battery test (P trend = 0.019 and P trend = 0.01, respectively)
McDermott et al., 2008, J Am Geriatr Soc 28	PAD	424/271	Isometric knee extension/plantar flexion strength Handgrip strength Knee extension power	‐	6‐min walk test 4‐m walking velocity test	Lower arterial brachial index values were associated with lower plantar flexion strength (P trend = 0.04) and lower knee extension power (P trend < 0.001)
Kuo et al., 2008, J Gerontol A Biol Sci Med Sci 38	PAD	206/1592	Isokinetic dynamometer	‐	20‐ft timed walk test	PAD associated with weak leg force, low gait speed and functional dependence (based on multiple logistic regression analyses)