I've just finished a months placement in the UK on elective orthopaedics lower limb, primary TKR and THR and revisions.

At the hospital I was working at, we followed protocols. Surgeons gave their post-op instructions regarding weight bearing status, bed rest (if revision or complicated) and they may have to wear a brace for 3 months (to prevent dislocation).

Contra-indications
No bending the trunk beyond 90 degrees
No crossing of legs (adduction beyond neutral)
No twisting on operated leg (ie step round when walking)

The following was used on initial ax, day 1 post-op
Check pt obs, BP, Sats, temp, early warning markers such as pain.

Check wound dressing for excess bleeding, and check for drains and aqu-fuse (Wikipedia reference-linkanti-inflammatory and pain control) at site.
Check neuro sensation (sensory and motor) on operated leg.

Motor Strength
Plantar Flexion and Dorsi Flexion = can they reach plantar grade ?

Quads - SQC - straight leg, put your hand under their knee and ask them to push their knee in to your hand.
- IRQ - rolled up towel under the knee, ask pt to pull toes back to nose and push knee down in to towel to raise foot off bed.
Put your hand above the foot....as a target.
- SLR - can they lift their leg up off the bed, without bending their knee.

Hamstrings - while in bed, slight bend in knee, your hand under their heel and ask them to push down/back in to your hand.

SGC - ask them to squeeze their butt cheeks together. When mobilising in bed, we encouraged the pt's to walk their butt cheeks one by one.

The main problem was weak IRQ and weak glutes due to previous immobility and surgical procedure (cutting thro glutes etc).

Hope this helps.