Rehabilitation Guidelines After Knee Replacement Surgery

Early Postoperative Phase (First Week)

The British Journal of Sports Medicine recommends beginning isometric quadriceps exercises in the first week to reactivate the quadriceps muscles, provided they cause no pain 2, 3
Immediate weight bearing with correct gait pattern should be implemented in the first week, with no pain, effusion or increase in temperature 2, 3
Cryotherapy should be applied in the first postoperative week to reduce pain 2, 4, 1
Immediate knee mobilization should be started within the first week to increase joint range of motion, reduce knee pain and prevent complications like extension deficit 1, 5
Neuromuscular electrical stimulation (NMES) can be considered as an addition to isometric strength training for re-educating voluntary contraction of the quadriceps muscles 2, 4, 6

Closed kinetic chain (CKC) exercises should be begun from week 2 postoperative 2, 3
Progression from isometric exercises to concentric and eccentric exercises should be done when the quadriceps is reactivated and the knee doesn't react with effusion or increased pain 2, 3
Supervised rehabilitation with a physiotherapist should be continued, though home-based rehabilitation may be suitable for highly motivated patients 2, 7

Open kinetic chain (OKC) exercises should be started from week 4 postoperative in a restricted range of motion (ROM) of 90–45° 2, 7, 1
For bone-patellar tendon-bone (BPTB) grafts, extra resistance is allowed at this stage 2
For hamstring (HS) grafts, adding extra weight should be avoided in the first 12 weeks to prevent graft elongation 2, 1
ROM in OKC exercises should be gradually increased: to 90–30° in week 5, to 90–20° in week 6, to 90–10° in week 7, and to full ROM in week 8 2, 3

Neuromuscular training should be added to strength training to optimize self-reported outcomes and prevent reinjuries 2, 4, 1
Rehabilitation should be continued for 9–12 months, depending on the final return-to-work or play goals 2, 3
Quadriceps and hamstring strength should be measured regularly to track progress 2
Psychological changes during rehabilitation should be evaluated using objective instruments 2, 3

An extensive test battery for quantity and quality of movement should be performed before returning to sports or demanding activities 2, 3
Strength tests, hop tests, and quality of movement assessments should be included 2, 8
A Limb Symmetry Index (LSI) of >90% should be used as a cut-off point for general activities 2, 8
For pivoting/contact sports, an LSI of 100% should be aimed for 2

Supervised rehabilitation should be continued for optimal outcomes, especially for complex cases 2, 1
Home-based physiotherapy may be as effective as outpatient clinic-based therapy for motivated patients 7, 4

Continuous passive motion should be avoided as it is not recommended by most guidelines 4, 1
Postoperative functional bracing is generally not recommended 4, 1

Delaying mobilization can lead to stiffness and extension deficits 1
Failing to address quadriceps strength deficits can significantly impact long-term functional outcomes 2, 9
Progressing too quickly with open kinetic chain exercises with hamstring grafts can lead to graft elongation 2, 3
Neglecting neuromuscular training alongside strength training increases risk of reinjury 2, 4
Discontinuing rehabilitation too early (before 9-12 months) may compromise optimal functional recovery 2, 3