Table 5 Characteristics of Quantitative Studies

Spinal manipulation

 Evans (United States) RCT [33]

2018

185

Adolescents (12–18 years) with nonspecific LBP with or without leg pain, VAS ≥ 3/10; subacute/recurrent (current episode 2–12 weeks duration with at least one similar episode in the past year) or chronic (current episode ≥ 12 weeks duration)

I: 15.5

C: 15.3

I: 1.6

C: 1.8

I: 65 (70%)

C: 62 (67%)

Type: SMT + Exercise

SMT: provided by chiropractors; techniques: high velocity low amplitude (preferred), low velocity low amplitude mobilization, flexion-distraction or drop-table assisted; up to a few minutes of ice/heat or soft tissue massage as needed

Duration: 12 weeks

Frequency: 1–2 x/week (20-min sessions); 8–16 sessions total

Setting: clinic

Exercise: provided by chiropractors or exercise therapists; self-care education; supervised sessions; components: aerobic, stretching, strengthening; home exercises accompanied by 20–40 min of aerobic activity

Duration: 12 weeks

Frequency: Supervised exercises: 1-2x/week (45-min sessions), 8–16 sessions total; Home exercises: 2x/week

Setting: clinic/home

Type: Exercise (provided by chiropractors or exercise therapists; self-care education; supervised sessions; components: aerobic, stretching, strengthening; home exercises accompanied by 20–40 min of aerobic activity)

Duration: 12 weeks

Frequency: Supervised exercises: 1-2x/week (45-min sessions), 8–16 sessions total; Home exercises: 2x/week

Setting: clinic/home

 Selhorst (United States) RCT [22]

2015

35

Adolescents (13–17 years) with nonspecific LBP < 90 days duration

14.88

1.27

21 (62%)

Type: SMT + Exercise

SMT: provided by physical therapists; technique: side-posture lumbar manipulation performed on symptomatic side

Duration: 1 week

Frequency: 2x/week

Setting: Clinic

Exercise: provided by physical therapist; components: lumbar stabilization, range of motion, postural training, core strengthening, stretching, addition of high-level functional exercises as indicated to promote return to activity

Duration: 4 weeks

Frequency: 2x/week

Setting: Clinic

Type: Sham SMT + Exercise

Sham SMT: provided by physical therapists; technique: patient side-lying, therapist passively flexed both hips to achieve slight lumbar flexion at patient’s most painful vertebral level, equal and opposite force applied to spinous process with both hands without inducing motion

Duration: 1 week

Frequency: 2x/week

Setting: Clinic

Exercise: provided by physical therapist; components: lumbar stabilization, range of motion, postural training, core strengthening, stretching, addition of high-level functional exercises as indicated to promote return to activity

Duration: 4 weeks

Frequency: 2x/week

Setting: Clinic

Group-based exercise

 Fanucchi (South Africa) RCT [34]

2009

72

Children (12–13 years) with low back pain in the previous three months

12.3

0.7

I: 15 (38.5%)

C: 18 (54.6%)

Type: Progressive exercise (instruction provided by PT; 10–15 min educational session about the importance of exercise, core musculature, posture and spinal alignment; weekly home exercise program including class-taught exercises; continuation of normal physical education classes, sports, and physical activity)

Duration: 8 weeks

Frequency: 1x/week (40–45 min sessions)

Setting: School

Type: Control (no intervention; continuation of normal physical education classes, sports, and physical activity)

Duration: 8 weeks

Frequency: N/A

Setting: N/A

 Harringe (Sweden) Cohort study [40]

2007

With and without LBP: 51 (I: 33; C: 18)

With LBP: 24 (I: 15; C: 4)

Female top level national gymnasts (11–16 years) with LBP (pain between the 12th rib and gluteal folds) more than 1 day during a 4-week baseline period

I: 13

C: 14

I: 11–15

C: 12–16

I: 15 (100%)

C: 4 (100%)

Type: Specific segmental muscle control exercises (group training program provided by PT; abdominal hollowing with progression: prone, four-point kneeling, prone with diagonal elevation of arm and leg, standing on balance board, in a basic trampette jump; 10 repetitions using 10-s holds; pressure biofeedback unit used initially to ensure correct muscle contraction)

Duration: 8 weeks

Frequency: 3–4 times/week

Setting: Gymnasium

Type: Control (visits provided by PT; given time for questions regarding injuries; provided advice and regime)

Duration: 8 weeks

Frequency: 3–4 times/week

Setting: Gymnasium

 Jones (1262 and 1267) (United Kingdom) RCT [35, 36]

2007

62

Adolescents (Grade 9 and 10 students) with recurrent nonspecific LBP as determined using a standardized questionnaire

I: 14.6 C: 14.6

I: 0.6

C: 0.5

Not reported

Type: Exercise rehabilitation (group-based; progressive program of strengthening and stabilization, range of motion, and aerobic exercises for the back and lower extremity; standardized with respect to number of exercises, repetitions, progression and schedule)

Duration: 8 weeks

Frequency: 2 x/week (30-min sessions)

Setting: school (home exercise encouraged)

Type: Control (continue normal daily activities)

Duration: 8 weeks

Frequency: N/A

Setting: N/A

 Vitman (Israel) RCT [39]

2022

33

Children and adolescents (10 – 18 years) with LBP

I: not reported

C: not reported

I: not reported

C: not reported

Not reported

Type: Weekly physiotherapy + monthly physiotherapy and home exercise

Weekly physiotherapy: 45-min group session with two physiotherapists, 21-exercise group therapy program

Duration: 12 weeks

Frequency: 1x/week

Setting: Clinic

Monthly physiotherapy and home exercise: same as the comparison group

Type: Monthly physiotherapy (i.e., personally-tailored comprehensive training) and home exercises

Physiotherapy: 40-min session consisting of personally tailored training for muscle endurance, flexibility, and strength, as well as instructions on body awareness and application of biomechanical and ergonomic principles

Home exercises: 5–6 individualized exercises, 1 set 10 repetitions (10–15 min/day). Diary kept of home practice to monitor

Duration: 12 weeks

Frequency: 1x/monthy

Setting: Clinic

Whole-body vibration

 Jung (Korea) RCT [37]

2020

50

Adolescents (10 – 19 years) with LBP ≥ 3 months, VAS ≥ 3/10 and able to perform sit-to-stand movements without assistance

I: 18

C: 18

I: 0.65

C: 0.68

I: 10 (40%)

C: 12 (48%)

Type: Whole-body vibration + trunk stabilization exercise

Six exercises (squat, bridge, single bridge and knee flex, side bridge, plank) performed on whole-body vibration machine (15 Hz and 2 mm amplitude). Exercise duration was 60 s for single bridge, bridge and knee flex, and plank or 90 secs for squat, bridge, side bridge, performed for 2 sets with 30 s break in between

Duration: 12 weeks

Frequency: 3x/week

Setting: Clinic (supervised by physiotherapist)

Type: Trunk stabilization exercise

Six exercises (squat, bridge, single bridge and knee flex, side bridge, plank). Exercise duration was 60 s for single bridge, bridge and knee flex, and plank or 90 secs for squat, bridge, side bridge, performed for 2 sets with 30 s break in between

Duration: 12 weeks

Frequency: 3x/week

Setting: Clinic (supervised by physiotherapist)

Cognitive functional therapy

 Ng (Australia) RCT [38]

2015

36

Adolescent male rowers (14–19 years) with nonspecific LBP, VAS > 3/10

I: 16.3

C: 15.2

I: 1.5

C: 1.5

0 (0%)

Type: Cognitive functional approach (provided by a physiotherapist; components: education, discussion about factors contributing to back pain, movement training and body awareness, functional integration, conditioning)

Duration: 8 weeks

Frequency: 1x/week for first two weeks, 1x/2 weeks for remainder (1 h initial; 30-min subsequent); total 5 sessions

Setting: local rowing club or university laboratory

Type: Control (no intervention; free to seek treatment from other providers)

Multimodal care

 Ahlqwist (Sweden) RCT [32]

2008

45

Adolescents (12–18 years) with nonspecific LBP (lumbar pain in a defined area); referred by a physician or nurse; VAS > 2/10

I: 15

C: 14

I: 13–18

C: 12–17

I: 15 (65%)

C: 16 (73%)

Type: Individualized physical therapy and exercise + standardized home exercise + education

Individualized physical therapy and exercise: exercises supervised by a physical therapist (15 reps/exercise; general and specific exercises including conditioning, active and passive mobility, strengthening and coordination; resistance gradually increased); individualized therapy (manual therapy, mechanical diagnostic therapy)

Duration: 12 weeks

Frequency: 1x/week

Setting: clinic

Standardized home exercise: body weight for resistance; 2 sets of 10 reps/exercise

Duration: 12 weeks

Frequency: 2x/week

Setting: home

Education: functional anatomy, ergonomics, pain management

Frequency: 1 session

Setting: clinic

Type: standardized home exercise + education

Self-training: conditioning exercises (brisk walks, jogging, bicycling, swimming)

Duration: 12 weeks

Frequency: 3x/week

Setting: home; follow-up in clinic at 1 week; follow-up by telephone at 6 weeks

Standardized home exercise: body weight for resistance; 2 sets of 10 reps/exercise

Duration: 12 weeks

Frequency: 3x/week

Setting: home

Education: functional anatomy, ergonomics, pain management

Frequency: 1 session

Setting: clinic

 Selhorst (United States) Cohort study [41]

2021

16

Adolescent (12 – 19 years) athletes (participating in sport activity ≥ 2 times/week prior to the onset of LBP) who reports acute LBP (< 3 months) that increases during lumbar extension

I: 14.5

C: 15.5

I: 12.1

C: 1.4

I: 5 (62%)

C: 3 (38%)

Type: Physical therapist guided functional progression program (PT First)

No advanced imaging was obtained at the beginning of the treatment

PT First Program 3-phase program:

Participants were on rest from their sport

Phase I: core strengthening in neutral spine, directional preference if identified, hip strengthening, peri-scapular strengthening, flexibility exercises, manual therapy as needed, modalities for pain (sparingly)

Phase II: core strengthening in functional range, hip and peri-scapular strengthening, flexibility exercises, manual therapy (sparingly), light running, jumping

Phase III: Return to sport activity with focus on functional return to all aspects of sport

Patients who fail to progress after 5 weeks either were treated as a presumed spondylolysis or had advanced imaging. They received two months of rest except for daily activities and home exercise program, following this, they completed physical therapy before returning to sport

Duration: Variable

Frequency: 2x/week

Setting: Clinic

Type: Biomedical model

Advanced imaging was obtained to diagnose the injury and participants diagnosed with non-specific LBP or spondylolisthesis

Patients with non-specific LBP: physical therapy and progressed to sport immediately

Patients with a bony or spondylolytic injury: preliminary 2–3 month rest from activity, bracing if indicated, followed by 4–6 weeks of physical therapy. Physical therapy was individualized based on patient’s presentation

Physical therapy:

Duration: 4–6 weeks

Frequency: 2x/week

Setting: Clinic