Table 4.

Motor Performance

Study	N	Age range/mean	Diagnoses	Non-SCD Control	Relevant Outcome Measures	Findings Related to Physical Impairments and Function
Armstrong et al. 201356	193	7–18 months/12.7 ± 2.7mo	HbSS HbSβ0	No	Bayley Scale of Infant Development, 2nd edition (BSID-II) Psychomotor Development Index (PDI) Vineland Adaptive Behavior Scales (VABS)	Participants with SCD presented with scores within the average range for BSID-II, PDI, and VABS motor skills BSID-II, PDI (5.7% ≤ 70 or < 10th percentile; 7.7% 70–84 or 10th −29th percentile; 86.5% ≥ 85 or ≥ 30th percentile VABS Motor Skills (0% ≤ 70 or < 10th percentile; 1.6% 70–84 or 10th −29th percentile; 98% ≥ 85 or ≥ 30th percentile
Brousse et al. 20205	51	5–17 years/11.9 ± 3.8 years	HbSS HbSβ0	No	6-minute walk test (6MWT)	6MWT distance (531–593 ± 38–76 m) Percentage of expected 6MWT distance (72–76 ± 7–10%)
Brownell et al. 202037	22	9–12 years/13.8 ± 3.3 years	HbSS	No	Jump Height Bruininks-Oseretsky Test of Motor Performance, 2nd edition (BOT-2)	Jump Height (33.2 ± 9.9 cm) BOT-2 total score (67.4 ± 6.1)
Burkhardt et al. 201749	32	7–17.25 years/11.14 ± 4.48 years	HbSS HbSC HbSβ0	Yes	WACOM fine motor-digital writing tablet	Participants with SCD performed worse on the WACOM writing tablet task for frequency, automatization, velocity, and variability. WACOM frequency z-score (SCD: −0.95 ± 1.49); p ≤ 0.001 WACOM automatization z-score (SCD: 0.57 ± 1.62); p ≤ 0.02 WACOM velocity z-score (SCD: 0.70 ± 2.09); p ≤ 0.02 WACOM variability z-score (SCD: 0.53 ± 1.30); p ≤ 0.02 WACOM pressure z-score (SCD: 0.15 ± 0.96); NS
Dedeken et al. 20146	46	6.1–19.7 years/12 years	HbSS HbSC HbSβ0 HbSβ+	No	6-minute walk test (6MWT)	6MWT distance (551 ± 92 m) 6MWT distance % of predicted: Silent infarct (74.9%) No silent infarct (86.0%) All (83.2 ± 12.1%)
Dougherty et al. 202039	21	5–20 years/11 ± 4 years	HbSS	Yes	Maximal jump height Bruininks-Oseretsky Test of Motor Performance (BOT)	Jump height (SCD: 25.2 ± 5.2 cm; controls: 28.0 ± 8.3 cm) BOTMP total score (SCD: 61.5 ± 14.0; controls: 62.3 ± 15.2)
Drazen et al. 201550	43	1–34 months/8.8 ± 7.5 months	HbSS HbSC HbSβ0 HbSβ+ SPFH	No	Bayley Scale of Infant Development, 3rd edition (BSID-III)	BSID-III, fine motor (p < 0.001): mean 8.0 ± 2.6, Scores of ≤ 7 (31.7%) BSID-III, gross motor (p = 0.009): mean 8.7 ± 2.9; Scores of ≤ 7 (32.6%)
Glass et al. 201357	80	Mean: 20.5 months	HbSS HbSC	No	Bayley Scales of Infant Development, 2nd edition (BSID-II)	Participants with SCD overall, on average, presented with no motor delay. Bayley Motor Index: 89.1 ± 14.4
Hostyn et al. 20138	46	6–18 years/9.15 ± 3.06 years	HbSS HbSC HbSβ0 HbSβ+	No	6-minute walk test (6MWT)	6MWT distance: All (480.89 ± 68.70 m) HbSS/HbSβ0 thalassemia (459.30 ± 57.19 m) HbSC/HbSβ+ thalassemia (502.39 ± 73.6 m)
Melo et al. 20179	57	6–18 years/11.9 ± 3.5 years	HbSS	Yes	6-minute walk test (6MWT)	6MWT distance (SCD: 500.6 ± 88.7; controls: 536.3 ± 94); p = 0.09, NS
Millis et al. 199451†	30	Only 10-year olds	HbSS	Yes	Swimming tests (20 yard and 40 yard) Potato race (100 yard)	Participants with SCD had decreased performance on 20-yard swim, 40-yd swim, and 100-yard potato race 20-yard swim (SCD: 23.1 ± 0.6* sec; controls: 8.9 ± 0.5* sec†); p < 0.05 40-yard swim (SCD: 46.7 ± 1.0* sec; controls: 22.9 ± 0.7* sec†); p < 0.05 100-yard potato race (SCD: 29.9 ± 0.7 sec; controls: 21.4 ± 0.5* sec); p < 0.05 % time difference: 20-yard swim (160 ± 16*%) 40-yard swim (104 ± 28*%) 100-yard potato race (40 ± 58*%)
Möckesch et al. 20177	46	10–16 years/15 ± 2.4 years (HbSS) 15.1 ± 2.6 years (HbSC)	HbSS, HbSC	No	6-minute walk test (6MWT)	6MWT distance: 78% of participants with SCD (HbSS: 79%, HbSC: 77%) performed an abnormal (<80% of normative value indicates abnormal) 6MWT compared to age-standardized predicted distance No difference between 6MWT distance between HbSC and HbSS.
Moheeb et al. 200710	50	9–12 years/10.1 ± 0.076 years	HbSS	Yes	Vertical jump height	Participants with SCD had lower jump height compared to controls Jump height (SCD: 17.7 ± 0.8* cm; controls: 23.1 ± 0.8* cm); p < 0.001
Newby et al. 201852	67	5–18 years/11.36 ± 3.51 years	HbSS HbSC HbSβ0 HbSβ+	Yes	Grooved Pegboard Test	Participants with SCD performed Grooved Pegboard fine motor dexterity test within the average range (SCD: 89.62 ± 3.08; controls: 92.08 ± 3.56); NS
Schatz & Roberts 200753	61	12–18 & 32–40 months/14.8 ± 2.6 & 37.3 ± 3.4 months (HbSS/HbSβ0); 15.9 ± 2.1 & 36.1 ± 2.5 months (HbSC/HbSβ+)	HbSS HbSC HbSβ0 HbSβ+	No	Denver-II fine motor scale Vineland Adaptive Behavior Scales (VABS) motor domain	Denver II- fine motor developmental quotient: HbSS/HbSβ0 12–18 months (98.7 ± 19.0) HbSC/HbSβ+ 12–18 months (86.4 ± 13.3) HbSS/HbSβ0 32–40 months (85.8 ± 13.8) HbSC/HbSβ+ 32–40 months (83.2 ± 14.0) VABS motor standard score: HbSS/HbSβ0 12–18 months (100.0 ± 5.9) HbSC/HbSβ+ 12–18 months (101.1 ± 4.3) HbSS/HbSβ0 32–40 months (88.9 ± 10.7) HbSC/HbSβ+ 32–40 months (86.6 ± 14.9)
Zempsky et al. 201354	25	7–21 years/16.6 ± 2.4 years	HbSS HbSC HbSβ+	No	Functional Independence Measure (FIM)	FIM motor score significantly improved during hospitalization for participants with SCD FIM motor (first day of hospitalization: 54.1 ± 11.8; last day of hospitalization: 65.8 ± 12.4); p < 0.001
Zempsky et al. 201455	159	7.26–21.82 years/15.73 ± 3.63 years	HbSS HbSC HbSβ0 HbSβ+	No	Functional Independence Measure (FIM)	Mean FIM 56.65 ± 15.23

Abbreviations: N = number of participants with sickle cell disease; NS = not significant; SCD = Sickle Cell Disease; SPFH = S persistent fetal hemoglobin. Results are reported as mean ± standard deviation, except where noted otherwise.

^*Standard error.

^†The unusually fast reported times for 20- and 40-yard swim for control sample were unable to be validated due to unsuccessful attempts to contact the corresponding author.