Table 4.

Characteristics of the Therapeutic Interventions in the Included Trials

Authors	Control Group Treatment	Exercises Performed	Exercise Variables	Nonexercise Care	Treatment Period and Frequency
Dursun et al53	Exercise only	Quadriceps setting, straight-leg raises, hip adductor strengthening, terminal knee extensions, and closed kinetic chain exercises; hamstrings, triceps surae, iliotibial band, and quadriceps stretching; proprioception training; bicycling	Duty cycle 10:20 s	NA	4 wk, 5 d/wk (EMGB group wore the device only 3/5 weekly sessions)
Yip and Ng49	Exercise only	Quadriceps, hamstrings, gastrocnemius, hip adductors, and iliotibial band flexibility; quadriceps setting, terminal knee extension, semisquat, wall slide, lunge, step-up, step-down, eccentric hamstrings exercise, and hip adduction exercises; balance and proprioception training; plyometric and agility training	NA	NA	8-wk daily home exercise program
Draper50	Exercise only	Quadriceps setting, straight-leg raises, active and passive range of motion, isokinetic exercises	1 wk postoperatively: 10 repetitions2 wk: increased repetitions4 wk: straight-leg raises, 5 sets of 10 each in prone, supine, and side-lying position	Electric stimulation progress to weight bearing tolerated at 12 wk	12 wk (18 or 26 sessions, depending on the patient's schedule)
Draper and Ballard51	Exercise and electrotherapy	Quadriceps setting, straight-leg raises, active and active-assistive range of motion, hamstrings stretching, isotonic knee extension and flexion exercises	Duty cycle 10:20 s (in conjunction with EMGB or electrotherapy), 3 sets of 10 (wk 1–2), 5 sets of 10 (wk 3–6), progressively increasing intensity	Progress to weight bearing as tolerated at 4 wk	6 wk total wk 1–4: daily home exercise program, 3×/d wk 5–6: 3 sessions/wk at rehabilitation clinic
Kirnap et al54	Exercise only	Phase 1: quadriceps setting, straight-leg raises Phase 2: hip adductor strengthening and terminal knee extension added Phase 3: closed kinetic chain exercises and lateral step-up exercises added	Duty cycle 5:10 s over 20 cycles	Cryotherapy and patellar mobilization	2 wk, 5 d/wk
Levitt et al55	Exercise only	Quadriceps setting	Duty cycle 5:10 s	NA	10-d home exercise program, 3×/d
Durmus et al52	Exercise and electrotherapy	Isometric knee extension (EMGB at 25°–30° knee flexion, electrotherapy at 60° knee flexion)	EMGB duty cycle 10:50 s, electrotherapy duty cycle 10:10 s	NA	4 wk, 5 d/wk
Yilmaz et al56	Exercise only	Quadriceps isometrics, minisquats, hip adductor isometrics, 4-way straight-leg raises, terminal knee extension	10 repetitions	NA	3 wk, 3×/d, both supervised group and home exercise programs

Abbreviations: EMGB, electromyographic biofeedback; NA, not available.