Posterior Cruciate Ligament (PCL)

Where is it painful for a client with a PCL lesion?

Classical patient features for a PCL lesion

Age: Average age is 32.7 years

Gender: Male incidence is higher than female 2: 1

Activities / Sport: Football, soccer, skiing, motor vehicle racing, motor vehicle accidents

Area of symptoms for a PCL lesion

- Widespread around the knee as injury does not commonly occur in isolation

- Feelings of unsteadiness or discomfort // for both acute and idiopathic injuries

- Common to report anterior knee pain whilst completing functional activities

- Less common however patients can report pain in the back of the knee

- Retropatellar knee pain

Characteristics of symptoms for a PCL lesion

- Tightness and restriction // likely due to the mild/moderate effusion

- Patient reports vague symptoms compared to other ligamentous structures at the knee

- Knee stiffness (depending on the level of chondral injury)

- Deep aching pain // often low in intensity

- intermittent symptoms

Typical activity capability/restriction for a client with a PCL lesion

- Pain and discomfort when descending stairs, ramps and decelerating.

- Difficulty with weight-bearing in a semi-flexed position e.g. squatting and walking long distances

- Walking on uneven surfaces // patient will often complain of knee instability or feelings of giving way

Behaviour of symptoms for a a PCL lesion

Aggs: Hyper-extension, kneeling (posterior knee pain), deceleration, going downstairs, running.

Ease: Pillow under the knee, bracing, rest, ice

24-hour pattern: Mechanically related

Typical history of a client with a PCL lesion

- Patient reports a traumatic blow most commonly to the anterior portion of the proximal tibia

- Will have an acute onset of pain following the trauma

- Mechanism commonly a direct blow to the proximal tibia, a fall on the knee with the foot in plantarflexion and hyperextension with combined rotational forces

- 50% of positive tests occur secondary to sporting injuries

- PCL implicated in 40% of acute knee instability presentations

- Another common mechanism are motor vehicle accidents (impact on the tibia forcing it posteriorly)

- 2-3% of chronic PCL presentations with unknown mechanism of injury

Pathobiological mechanisms underlying a PCL lesion

- Nociceptive pain mechanism at initial presentation

- Due to commonly reported instability at the knee it is important to understand patients confidence levels especially with loaded activities in aggravating position

- If a patient feels like a knee is going to give way or not support they will alter their behaviour accordingly. This pathway will lead to increased nociplastic influences on the patient’s presentation.

Proposed pathology for a PCL lesion

- PCL can be compromised at the mid substance, or there may be an avulsion from the anterior aspect

- Isolated PCL damage occurs in athletics, multiple structures may be involved if there is high energy trauma.

-Typically PCL injuries are combined with other ligamentous, chondral (52%) and meniscal injuries (16-28%).

Grading of injury (posterior translation in relation to the femur)

- Grade 1 (0-5mm)

- Grade 2 (5-10mm)

- Grade 3 (>10mm)

Physical impairments & associated structure/tissue sources (ie P/E findings)

Local

- Symptoms are vague and minimal.

- Minimal pain

- Minimal swelling // intraarticular

- Full ROM into flexion

- 5 to 10 degrees deficit into extension // likely full ROM if an isolated injury

- reduced strength if chronic or pain inhibition

- bruising

- reduced gastrocnemius strength

Special tests

- Posterior drawer at 90 deg knee flexion (sensitivity 0.22-1.00; specificity 0.98)

- Posterior sag test (sensitivity 0.46-1.00; specificity 0.89)

- Quadriceps active test (sensitivity 0.53-0.98; specificity 0.96-1.00)

- Reverse pivot shift test (sensitivity 0.19-0.26; specificity 0.95)

Remote

- unlikely to have any changes if acute

General

- adaptive gait changes

- reduced confidence with landing and change of direction

- feelings of giving way or instability

Typical contributing factors for a PCL lesion

Intrinsic - reduced gastrocnemius activation

Extrinsic - Reduced dynamic control, poor performance with jumping/landing etc

General - hypermobility and ligament laxity

Relevant precautions/ contraindications to P/E and treatment

- Depending on severity and irritability

- If acute, encourage RICER and limit assessment to P1

- Screen for a contusion of the tibia / popliteal ecchymosis

- Screen for DVT

- Screen for boney injuries

Relevant diagnostic imaging for a PCL lesion

X-rays - bony avulsion may be observed however won’t show any findings regarding the integrity of the ligament

Stress radiographs - may be used to correlate clinical findings

MRI (97% sensitive) - Gold standard, recommended if evidence of ligamentous injury

Typical prognosis for a PCL lesion

Return to play rate up to 67% of patients with grade 1 & 2 tears

Return to play rate 58-63% with operated tears grade 2 and above

- Long term consequences of isolated injury is unknown // mid-level evidence for the increased prevalence of meniscal injury, 80% of follow up group reported pain and 50% reported occasional swelling

- graft failure rate of 11% in isolated PCL reconstruction

- 7 years follow up // 23% of patients had arthritic changes

- 14 year follow up // 41% of patients had arthritic changes, of the 41%, 11% had moderate to severe OA

- noted that there was no control group so no comparison to normal age-related changes

Management/treatment selection for a PCL lesion

Isolated grade I or II PCL tears are most commonly managed conservatively. When a grade III tear is sustained acutely, along with other ligamentous injuries and/or with meniscus tears, surgery review is indicated.

Indications for surgery // or surgical review

- Grade III PCL injury WITH pain and instability

- Or instability and a failed conservative trial of management

Sample Rehabilitation outline from Brukner and Khan:

Phase 1

Duration: 6 weeks

Bracing: 2-4/52 -brace 0 ; then as below

NWB - WBAT - PWAB (1-4)

Exercises: ROM in prone; symptom Mx; isometric quads; SLR; weight shift; proprioception; DL strengthening (knee < 70 degrees flex)

Phase 2

Duration:6 to 12 weeks

Bracing: next 12-14/52 brace 0 - 110;

FWB

DL strengthening (knee < 70 degrees flex) ; SL proprioception;

Phase 3

Duration: 12 to 16 weeks

DL strengthening past 70 degrees; SL strengthening; jogging; agility

Phase 4

16 to 24 weeks

unrestricted strengthening; plyometrics; return to sport

Differential diagnosis for a PCL lesion

LCL/MCL // Will present with additional valgus/varus laxity

Posterolateral corner

ACL // Positive Lachmann's Test, positive anterior drawer test, positive pivot shift test

Neural (tibial/peroneal nerve) // differentiated by a neuro exam

Vascular (popliteal vein + artery) // differentiated by a vascular exam, Doppler Ultrasound

Tib Plateau/fibula/shaft/Segond fracture // differentiated imaging

Meniscal injury // Positive Thessaly / McMurray's Test / Appleys

Pes anserine // Tenderness over insertion, RSC of adductors

S1/S2 Nerve Root // Slump, Neurological, Reflexes

Plica // Pain with patella compression and medial glide

Baker's Cyst // Palpation, area of swelling

Osteochondritis Dessicans // Stiffness through ROM

Biceps Femoris Tendon Injury // Focal tenderness, pain with hamstring RSC, reduced hamstring length

Popliteus, plantaris muscle injuries // Tenderness in popliteal space, dynamic assessment

References

Brukner P, Khan K. Clinical sports medicine (volume 1 injuries). 5th ed. Australia: McGraw-Hill Education; 2017.

Bahr R. The IOC manual of sports injuries. 1st ed. Sweden: International Olympic Commitee; 2012.

Castro, C & João, T 2019, 'Intrinsic and Extrinsic Risk Factors for Lateral Ankle Sprain: A Literature Review', Archives of Sports Medicine, vol. 3, 09/14.

D’Amato, M 2018 'Posterior Cruciate Ligament Injuries' in C Giangarra & R Manske (eds) Clinical Orthopaedic Rehabilitation, Elsevier, Philadelphia, PA, pp - 359-367

Fowler, PJ & Messieh, SS 1987, 'Isolated posterior cruciate ligament injuries in athletes', The American Journal of Sports Medicine, vol. 15, no. 6, 1987/11/01, pp. 553-57.

Heyworth, J 2003, 'Ottawa ankle rules for the injured ankle', BMJ (Clinical research ed.), vol. 326, no. 7386, pp. 405-06.

Schüttler, KF, Ziring, E, Ruchholtz, S & Efe, T 2017, '[Posterior cruciate ligament injuries]', Unfallchirurg, vol. 120, no. 1, Jan, pp. 55-68.

Sheng, A 2019, 'Postereior Cruciate Ligament Sprain' in Walter F, Julie K.S, Thomas D.R (eds) Essentials of Physical Medicine and Rehabilitation Musculoskeletal Disorders, Pain and Rehabilitation, Elsevier, Philadelphia PA, pp - 424 - 430

In association with Peter Migliore and Sanjana Soni