Table 1.

Key details of the studies included in the meta-analysis

Author, year of publication	Country	Study design	Subjects	Intervention and control groups; point of assessment	Key outcome
Cha et al. (2019) [15]	Korea	Quasi-experimental	Patients with metacarpal fracture Mean (SD) age (years) Group 1, 37 (12) Group 2, 40 (11) Proportion of male subjects (56/69)—82%	Group 1 (mini-open antegrade intramedullary nailing) Group 2 (open reduction with internal fixation; ORIF) Point of assessment: clinical and functional outcomes were assessed at least 2 years after surgery	Final shortening; mean (SD) in mm Group 1 (N = 36), 0.3 (0.7) Group 2 (N = 33), 0.1 (0.5) Final visual analogue score (VAS); mean (SD) Group 1 (N = 36), 0.3 (0.6) Group 2 (N = 33), 0.3 (0.6) Final DASH (disabilities of the arm, shoulder, and hand) score; mean (SD) Group 1 (N = 36), 4 (3) Group 2 (N = 33), 6 (3) Final range of movement (ROM) of the metacarpophalangeal joint (o); mean (SD) Group 1 (N = 36), 84 (4) Group 2 (N = 33), 85 (3) Final grip strength (% of the unaffected side); mean (SD) Group 1 (N = 36), 94 (5) Group 2 (N = 33), 91 (5)
Dreyfuss et al. (2018) [16]	Israel	Non-randomized study	Adult patients operated for metacarpal shaft fractures Mean (range) age of participants (in years) Group 1, 27.5 (18–55) Group 2, 29.4 (18–57) All male subjects	Group 1 (pinning using Kirschner wire) Group 2 (open reduction with internal fixation with locking plates and screws) Point of assessment: clinical and functional outcomes were assessed at least 1 year after surgery	Final shortening; mean (SD) in mm Group 1 (N = 39), 1 (0.8) Group 2 (N = 29), 0 (0.0) Final DASH score; mean (SD) Group 1 (N = 39), 15.6 (8.8) Group 2 (N = 29), 10.5 (6.7) Final range of movement (ROM) of the metacarpophalangeal joint (o); mean (SD) Group 1 (N = 39), 71 (24.2) Group 2 (N = 29), 86 (12.5) Final grip strength (% of the unaffected side); mean (SD) Group 1 (N = 39), 83 (11.6) Group 2 (N = 29), 93 (13.8)
Vasilakis et al. (2019) [17]	USA	Retrospective chart review	Patients aged over 16 years with single digit, closed isolated extraarticular metacarpal fracture Mean (SD) age (years) Group 1, 37.9 (17.8) Group 2, 36.8 (16.1) Proportion of male subjects (49/70)—70%	Group 1 (closed reduction with percutaneous pinning) Group 2 (open reduction with internal fixation) Point of assessment: clinical and functional outcomes were assessed between 3 and 6 months post-operatively	Final DASH score; mean (SD) Group 1 (N = 44), 16.3 (7.1) Group 2 (N = 26), 18.7 (6.6) Final range of movement (ROM) of the metacarpophalangeal joint (o); mean (SD) Group 1 (N = 44), 90.8 (14.8) Group 2 (N = 26), 86.7 (20.6)
Pandey et al. (2018) [18]	India	RCT	Patients aged 16–60 years with closed shaft fracture of metacarpal Mean age (years) of the participants, 29.34 Proportion of male subjects (28/32)—87%	Group 1 (closed reduction with percutaneous pinning using Kirschner wire) Group 2 (open reduction with internal fixation) Point of assessment: clinical and functional outcomes were assessed at 2 years post-operatively	Final DASH score; mean (SD) Group 1 (N = 16), 32.98 (18.2) Group 2 (N = 16), 36.76 (16.6) Final range of movement (ROM) of the metacarpophalangeal joint (o); mean (SD) Group 1 (N = 16), 95.34 (24.9) Group 2 (N = 16), 95.82 (23.7)
Fujitani et al. (2012) [19]	Japan	Prospective quasi-randomized	Patients with displaced metacarpal neck fracture Mean (SD) age (years) of the participants, 31 (11) Group 1, 28 (13) Group 2, 33 (8) Proportion of male subjects (26/30)—87%	Group 1 (closed reduction with percutaneous pinning using Kirschner wire) Group 2 (open reduction with internal fixation) Point of assessment: clinical and functional outcomes were assessed within 1 year post-operatively	Final shortening; mean (SD) in mm Group 1 (N = 15), 1.5 (0.4) Group 2 (N = 15), 0.7 (0.5) Final range of movement (ROM) of the metacarpophalangeal joint (o); mean (SD) Group 1 (N = 15), 93 (23) Group 2 (N = 15), 78 (23) Final grip strength (% of the unaffected side); mean (SD) Group 1 (N = 15), 67 (18.3) Group 2 (N = 15), 86 (20.9)
Ozer et al. (2008) [20]	USA	Prospective quasi-randomized	Patients with closed, displaced extraarticular metacarpal fracture Mean age (range) (in years) of the participants Group 1, 25 (19–45) Group 2, 28 (19–47) Proportion of male subjects (35/52)- 67%	Group 1 (intramedullary nail fixation) Group 2 (plate screw fixation) Point of assessment: clinical and functional outcomes were assessed at 18–19 weeks (i.e., ~ 5 months) post-operatively	Final shortening; mean (SD) in mm Group 1 (N = 38), 3 (0.83) Group 2 (N = 14), 0 (0.0) Final DASH score; mean (SD) Group 1 (N = 38), 9.47 (4.2) Group 2 (N = 14), 8.07 (4.5) Final range of movement (ROM) of the metacarpophalangeal joint (o); mean (SD) Group 1 (N = 38), 91 (14) Group 2 (N = 14), 83 (23)
Facca et al. (2010) [21]	France	Prospective comparative non-randomized	Patients with closed, isolated, displaced 5th metacarpal neck fractures Mean age (in years) of the participants, 32.1 Proportion of male subjects (34/38)—90%	Group 1 (intramedullary K-wire fixation) Group 2 (locked plate screw fixation) Point of assessment: clinical and functional outcomes were assessed at a mean follow-up period of 3.3 months in group 1 and 4.8 months in group 2, post-operatively	Final visual analogue score (VAS); mean (SD) Group 1 (N = 20), 0.9 (1.02) Group 2 (N = 18), 0.94 (1.14) Final DASH score; mean (SD) Group 1 (N = 20), 9.8 (7.99) Group 2 (N = 18), 15.88 (7.47) Final range of movement (ROM) of the metacarpophalangeal joint (o); mean (SD) Group 1 (N = 20), 98 (4) Group 2 (N = 18), 74 (20) Final grip strength (% of the unaffected side); mean (SD) Group 1 (N = 20), 92.9 (20.6) Group 2 (N = 18), 88.4 (19.0)
Gupta et al. (2007) [22]	India	Prospective comparative non-randomized	Patients aged ≥ 14 years with closed, stable, extraarticular, non-avulsive metacarpal fracture Mean age (in years) of the participants, 35.6 The study was conducted among male subjects	Group 1 (reduction with percutaneous K-wire fixation) Group 2 (open/closed reduction with external fixation using locked plate/screw) Point of assessment: clinical and functional outcomes were assessed at 3 months, post-operatively	Total active range of motion was excellent in 42% (13/31) and good in 48.4% (15/31) of the patients in group 1. In group 2, in 42.8% patients, it was excellent and in 28.6% patients it was good. The observed differences were statistically non-significant. Total active range of motion was defined in terms of percent regained motion compared to the normal range of digital motion (i.e., 260°); excellent 85 to 100%; good 70–84%; fair 50–69%; and poor < 50%
Takigami et al. (2010) [23]	Japan	Retrospective	Patients operated for metacarpal fractures Mean (SD) age (in years) of the participants Group 1, 36 (21) Group 2, 45 (20) Proportion of male subjects (53/71)—75%	Group 1 (reduction with percutaneous K-wire fixation) Group 2 (reduction with low profile plate and screw) Point of assessment: clinical and functional outcomes were assessed at 6–13 months of being operated	Total active flexion (TAF) was 235° ± 38° in the low profile plate and screw group and 243° ± 22° in the K-wire group. This difference was not statistically significant. Total extension lag (TEL) was 12° ± 20° in the LPP group and 9° ± 12° in the K-wire group (not significant).