Knee Problems

ACL Injuries

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Generally, the knee injuries that include rupture of the ACL (anterior cruciate ligament) are sporting injuries or work related injuries.
These are mostly non contact injuries and involve the foot being planted securely on the ground and the body twisting in the opposite direction. Often you will hear something pop in the knee and then there is collapse of the knee and pain, shortly followed by a lot of swelling. Commonly there are associated injuries such as meniscal (cartilage) tears or collateral ligament damage.
The ACL is the primary stabiliser of the knee and damage to it usually leaves you with a feeling of instability or a vague distrust that the knee will support you. If you are active and sporty and want to return to an active lifestyle, I will usually recommend surgery with ACL reconstruction.
The goal of surgery is to stabilise the knee and to reduce the risk of further injury to the knee due to instability


This is done through an arthroscope and is best done after 10 days to 2 weeks after the injury but can happen at any stage after the injury with the risk being that the longer you wait and the more muscle you lose, the more chance there is of secondary injury and the longer your rehab will be.
This operation is generally done under general anaesthetic. The hamstring tendon is harvested from just below the knee on the inside of the leg. The camera is inserted into the knee and the damaged tissue is cleaned out of the joint. Holes are drilled into the tibia and the femur, using a special drill that works from the inside of the knee and allows the graft to be pulled into the bone. There have been recent advances and developments in this surgery in that the position that the graft takes is now more anatomical. This means that the new ligament is very close to where the original was, which makes a lot of sense. The tendons are passed over a loop with a secure button which tightens and pulls the tendon up into the femur and tibia. We tighten the graft with the knee slightly bent, so that the tension is just right.

The most important part of the operation is the rehabilitation. I recommend an step by step program which usually takes approximately 8 or 9 months. Quicker rehab programs are out there but they may not be the best thing if you have had an anatomical reconstruction . Every patient is different and it is important to complete each step before moving onto the next. Sometimes the injury won’t settle down in time to keep to this program, so use it as a guideline only and listen to your physio or biokineticist to get better idea of how you are progressing.




  • Allow knee to settle post –op. Debulking of dressing day 1 or 2
  • Work within pain as it allows
  • Aim to remove crutches and walk normally
  • Reduce joint swelling
  • Aim at achieving full extension with active and passive movements
  • Use:    
    • Mobile – Ice knee pack 3-4 times a day
    • Quads and Hamstrings contractions at different angles of knee flexion
    • Patella mobs
    • Normal gait with full ext of knee and backsetting of knee
    • Early active Hamstring strengthening
    WEEKS 3 TO 5

    need to focus all attemp;ts on achiving full range of motion in flexion and extension, active and passive movements

    cycling to get rid of swelling and loosen knee

    knee cap mobilisations

    WEEKS 5 TO 12
  • Back to full activity
  • Reduce any persistent effusion
  • Full unrestricted range of motion
  • Proprioception and muscle strengthening & control
    • Mobile-Ice twice a day – morning and night
    • Wound massage – doesn’t matter what with
    • Active/ Active assisted/ passive strengthening and range of motion - 2kg Hamstring curls
    • Swimming – no breastroke
    • Persist with ROM and stretching exercises
    WEEKS 12 to 16
  • More intense work
  • Work on endurance
  • Use:
    • As Above (3 & 4)
    • Increase repetitions – low resistance – Hamstring curls
    • Extensive stretching exercises
    • Cycling (stationery), Stepper, Leg press
    • Begin with lunges
    WEEKS 16 – 24
  • Work on balance and proprioception
  • Increase strength and endurance
  • Use:    
    • Mobile –Ice once a day
    • Wobble board
    • Cycling +++++
    • Lunges, In- line hopping, squats
    • Begin in- line jogging on flat ground
    • Increase Hamstring and Quads power output
    • Begin with lateral stepping
    WEEKS 24 - 36
    • Prepare to return to specific activity
    • Incorporate agility and reaction time into proprioceptive work
    • Combination movements with lateral stepping, hopping, jumping etc.
    • Incorporate ball/other skills to remove emphasis from the knee
    • Aerobics classes
    • Increase leg strength
    • Sport specific