ACL Reconstruction: Brace vs. Cast — Current Standard of Care

After ACL reconstruction, a hinged knee brace is standard; a cast is not used in modern practice.

Why a Brace, Not a Cast?

Early Motion Is Critical: CPM/active-assisted ROM begins Day 0–1 to prevent arthrofibrosis, nourish cartilage, reduce stiffness.
Graft Protection ≠ Immobilization: Brace allows controlled motion (e.g., 0–90° weeks 1–2, progressive) while limiting harmful rotation/varus-valgus.
Muscle Preservation: Quadriceps inhibition is profound post-ACLR; immobilization accelerates atrophy. NMES + early weight-bearing in brace combats this.
Functional Rehab: Weight-bearing, closed-chain exercises, proprioception start early — impossible in a cast.

Concurrent fracture fixation requiring immobilization
Revision with severe bone loss/tunnel issues
Patient non-compliance risk (intellectual disability, severe behavioral issues) — still prefer articulated brace with locks.

Modern ACLR rehab is motion-driven. The brace is a protective guide, not a rigid cage. Follow your surgeon's specific protocol.

Phase	Brace Setting	Weight-Bearing
0–2 wks	Locked 0° ext for sleep/walking; unlocked 0–90° for exercises	PWB (25–50%) with crutches
2–4 wks	Unlocked 0–110°+	Progress to FWB
4–6 wks	May wean for therapy/ADLs	FWB
6+ wks	Discontinue per surgeon	Full