Table 2 shows the results of the included articles’ physiotherapeutic interventions. Again, there was a large variability between studies in physiotherapeutic exercise interventions used and type of outcome measures applied.

Based on the ICF scheme, the study results were grouped into three different categories: joint and muscle function, functional performance, and participation, with results for each category reported in 68%, 78%, and 78% of the studies, respectively. Different outcome measures and units of measurement were used within categories.

Joint and muscle functions were primarily measured in terms of ROM and strength. Joint ROM was reported in degrees and measured during both active and passive movement in 20 articles [32, 34,35,36,37,38,39,40,41, 43, 44, 47, 48, 52,53,54, 59, 60, 62, 64]. Hip abductor [34, 57, 60], quadriceps muscle [33, 57, 59,60,61], and hamstrings [33, 57, 59] strength were evaluated in three, five, and three articles, respectively. Strength values were measured in these units of measurement: pounds, kilograms, Newton normalized to BMI, and Newton-metres/kilograms. One article used the Index of Muscle Function (IMF) test to perform stress testing [35]. In 64% of the articles reporting on the outcome measure joint and muscle function, there was no statistically significant difference between IG and CG [33, 35,36,37,38,39,40, 42, 44, 47, 52, 54, 59,60,61,62, 66].

Functional performance measurements have been executed in various ways. A total of 17 measurements were used to obtain the intended results in the different articles. The 6-min walk test (6MWT) [33,34,35, 42, 43, 52, 55, 60] and the Timed Up and Go test (TUG) [33, 41, 44, 51, 58,59,60, 62, 64] were used in most studies to measure functional performance. Other studies measured and reported functional performance using subjects’ maximal walking speed [38, 39, 49, 51, 59, 64], the stair-climbing test [33, 35, 42, 44, 49, 60, 67], single-leg stance test [38, 49,50,51, 56, 60, 67, 68], figure-of-eight test [35, 42, 67, 68], functional reach test [58, 59], 10-min walk test [41, 50, 62], 30-s chair test [42, 44, 60], Berg balance scale [45, 58], and subjects’ step cadence [49,