Posterior cruciate ligament (PCL) reconstruction rehabilitation - A guide to rehabilitation following PCL reconstruction surgery

Introduction

PCL reconstruction is an operation to replace a torn posterior cruciate ligament and restore stability to the knee joint.

Anatomy of the knee joint

The PCL is one of four major ligaments that stabilises the knee joint.

A PCL injury typically occurs as a result of:

1. A non-contact injury with knee hyper-extension. These are often sporting injuries.
2. A direct blow to the tibia whilst the knee is bent. This often occurs as dashboard injuries during road traffic accidents.

PCL injuries are often associated with injuries to the ligaments and tendons on the posterolateral region of the knee such as lateral collateral ligament (LCL), anterior cruciate ligament (ACL) and/or the medial meniscus (cartilage), but it can occur in isolation.

The aim of PCL reconstruction surgery is to restore dynamic stability of the knee and to improve function. Rehabilitation is vital to ensure good functional outcomes following PCL reconstruction. Research shows that greater quadriceps (thigh muscle) strength is associated with better self-reported knee function and successful return to normal activities and sport.

This guide explains the rehabilitation process and gives exercises to perform following PCL reconstruction surgery. If you have had a repair of other structures in the knee such as the meniscus, the post-operative protocol may differ slightly and progression is usually expected to be somewhat slower. If this is the case, the physiotherapist on the ward will explain this to you.

Waling after the operation

You are usually able to take as much weight through your operated leg as pain allows (unless otherwise advised by your consultant or physiotherapist). You will be given elbow crutches. Use these for the first two weeks, or longer if your knee feels weak or you lack confidence. You will be provided with a PCL brace that should be to be worn for up to 24 weeks following your surgery or longer as specified by your consultant.

Swelling and pain

Some swelling and pain can be expected for the first few days to a week after your operation. If the knee is swollen, rest with your leg elevated and use ice (be sure not to get the wounds wet whilst using ice; wrap the ice in a towel). Pain levels are usually quite variable in your rehabilitation journey and this is normal.

Week 1 to 6 targets

• Decrease swelling in the knee.
• Ensure adequate pain control.
• Fully weight bear in PCL brace. Aim to restore normal walking pattern.
• Aim to achieve full knee extension (straighten). Avoid hyper-extension.
• Aim to achieve 0 to 90 degrees of knee flexion.
• Regain active quadriceps control. Be able to perform a straight leg raise with no lag (no bending of the knee).
• Restore proprioception (balance) and neuromuscular control.

Week 1 to 6 exercises

Ankle pumps

This exercise is designed to help with circulation. In a lying or sitting position (on the bed or sofa is fine), move your ankles up and down.

This should be performed regularly – at least every couple of hours. Repeat 8 to 12 times.

Static quads / knee extension

Lying on your back, push the back of your knee down into the bed whilst pulling your toes towards you. Hold and keep the knee straight for 5 to 10 seconds.

2 to 3 sets of 6 to 12 repetitions.

Little and often throughout the day.

Knee flexion

Lying on your back, bend and straighten your leg. Gradually increase range of movement as you are able.

Repeat 8 to 15 times.

Little and often throughout the day.

Straight leg raise

Lie on your back. Engage your thigh muscles. Keeping the leg straight, raise the whole leg off the bed and lower. Try not to let the knee bend.

2-3 sets of 6 to 12 repetitions.

Little and often throughout the day.

PASSIVE Hamstring Curl

Lie on your stomach. Allow your partner to gently bend and straighten your knee. Keep your muscles relaxed, do not try to help bend and straighten your knee. Do not go past 90 degrees.

Repeat 6 to 12 times.

2 to 3 sets.

Little and often throughout the day.

Hip Abduction/adduction

In standing, hold onto a solid support and lift your leg out to the side and back in.

2 to 3 sets of 6 to 12 repetitions.

Little and often throughout the day.

Seated Flexion

Sitting on a chair, gently bend your knee and slide your foot along the floor.

2 to 3 sets of 8 to 10 repetitions.

Note: In the case of increasing knee temperature, swelling or pain as a reaction to any of these mobilisation exercises, ease off the exercise causing discomfort. Use ice and elevation and discuss with your physiotherapist at your outpatient appointment.

Week 6 to 12

The graft is still healing to the bone at this time. Therefore, you should continue to take care to avoid falls. You would usually have seen a physiotherapist by this point who will be able to assist in the progression of exercises. It may be that you are referred to a group exercise class.

Evidence supports criteria-based progression rather than a strict time-based progression. This means that you should discuss your progression through these activities with your physiotherapist. It is important that you feel you have developed good leg strength and stability and that you only progress when you feel ready.

Week 6 to 12 targets

• Continue to wear the brace.
• Continue the exercises of weeks 1 to 6.
• Wean yourself off crutches if you can achieve a good straight leg raise.
• Able to maintain a static single leg stand (knee slightly flexed) on steady and unsteady surface.
• Maintain full knee extension, avoiding hyperextension.
• Commence passive knee full range of motion in supine and prone.
• Commence gentle hamstring stretches.
• Commence exercises for weight transference.
  • Double leg press up to 70 degrees.
• Gradual increase range of motion within limits of pain.
• Aim for 120 degrees of flexion (bending) by the end of week 12.
  • If you have 115 degrees knee flexion, commence stationary biking with zero resistance

Week 16 onwards targets

• Progress leg press past 70 degrees knee flexion.
• Commence isolated hamstring exercises.
• Progress to single leg bridges with knees flexed.
• Continue proprioception and balance exercises.
• Progress stationary bike resistance and duration.

Week 24 weeks onwards targets (3 to 6 months)

• Wean off brace after 24 weeks.
• Continue progressive strengthening.
• Promote proper movement patterns.
• Avoid post exercise pain/swelling.
• Aim to have full, pain-free active and passive range of movement, muscle strength and proprioception.
• Sport-specific training can begin once patient has gained enough strength and endurance at approx. 24 weeks.

Six months onwards and returning to normal sporting activities

Research indicates that the decision around return to sport should be based on meeting key performance criteria rather than based on time frames.

The earliest that you are likely to be able to return to sport is six months. Evidence shows that the risk of injury when returning to sport is significantly reduced when return-to-sport criteria are met and by waiting until nine months after your operation.

It is important to only progress your rehabilitation and look to start returning to sporting based activities when you feel ready. Evidence shows that there are psychological aspects of the rehabilitation to consider (as with any injury). It is important to understand that the psychological factors of rehabilitation are normal and will differ from person to person depending on their progress.

6 to 9 months

• Maintenance of strength, endurance, and function.
• Gradual return to running without pain and swelling.
  • Light running initially in a straight line.

Return-to-sport performance criteria often includes:

Progression at this stage of rehabilitation can be discussed with your outpatient physiotherapist.

The information in this leaflet guides you through the initial six weeks and onwards following PCL reconstruction surgery. The timescales described are for guidance only. The exact progress will vary depending on the individual.

You will normally see one of the orthopaedic consultant’s team in an outpatient appointment a few weeks after the operation. The physiotherapist on the ward will refer you to your local physiotherapy outpatients department for ongoing rehabilitation.

The information in this booklet follows recommended guidelines based on the available evidence and literature.

Contacts

If you have any concerns following discharge from hospital, the Surgical Hub physiotherapy team can be contacted on 01223 388160 or the Main Hospital physiotherapy team on 01223 216104. Should you wish to contact the Physiotherapy Outpatient department the number is 01223 216633.

References

Anderson et al, 2018 Acute Posterior cruciate Ligament Injuries: Effect of location, severity and associated injuries on the surgical management. Skeletal Radiology Acute posterior cruciate ligament injuries: effect of location, severity, and associated injuries on surgical management | Skeletal Radiology (springer.com) (opens in a new tab)

Gao et al. 2013 Effect of partial and complete posterior cruciate ligament transection on medical meniscus: a biomechanical evaluation in the cadaveric model, Indian Journal of orthopedcis Sept 2013. Effect of partial and complete posterior cruciate ligament transection on medial meniscus: A biomechanical evaluation in a cadaveric model - PMC (nih.gov) (opens in a new tab)

Posterior Cruciate Ligament Injury.

Longo UG, Viganò M, Candela V, De Girolamo L, Cella E, Thiebat G, Salvatore G, Ciccozzi M, Denaro V. Epidemiology of posterior cruciate ligament reconstructions in Italy: a 15-year study. Journal of clinical medicine. (opens in a new tab) 2021 Feb 1;10(3):499.

Massachusetts general Brigham Sports Medicine: rehabilitation Protocol for PCL Reconstruction

Rehabilitation-protocol-for-posterior-cruciate-ligament-pclr.pdf (massgeneral.org) (opens in a new tab)