Revista de Medicina Desportiva (English) May 2018 - Page 30

the sport and labor activity . Usually , symptoms are subtle , with a feeling of discomfort or pain in the posterior face of the flexed knee and slight swelling , even in acute injury . In chronic cases , they may experience irradiation of the pain to the anterior face of the knee and when going down the stairs , walk in inclined planes or when they slowdown . 6
Physical examination must be tested for all ligament and meniscus structures . To look for the injury of the PCL , the most commonly tests are :
• Posterior sag sign
• Quadriceps activation test
• Rear drawer
• Reverse pivot shift
• Dial test at 30 ° and 90 ° of knee flexion
• External rotation recurvatum test . In cases of a chronic injury , the gait may undergo changes with the attenuation of the PCL structures , characterized by external rotation , posterolateral deviation and hyperextension ( varus thrust ). There are devices , like arthrometer , that can be used , but the evidence has shown that it underestimates the posterior
23 , 24 translation . and PCL become the main rotational stabilizers , which leads to an excessive load on these structures . On the other hand , untreated chronic PCL or ACL injuries may cause attenuation of the remaining knee stabilizers . In this way , it must be known that the normal biomechanics of the knee comes from a synergy between the static and the dynamic stabilizer structures and that the rupture of the PCL will have influence on the kinematics of the knee , causing posterior subluxation of the tibia , with increased contact forces in the medial and patellofemoral compartment , and activation of compensatory mechanisms in the march . 5 , 6 , 22
Epidemiology and pathogenesis
The rupture occurs in 5-20 % of all knee ligament injuries and there is rarely an isolated injury , being associated with 79 % of PLC injuries . 5-7 It arises by :
• Sports trauma : more common with knee-bending and footsustained or with hyperextension movement ;
• Road accidents ( 57 %): high energy and often associated with multiligamental injuries . Taking into consideration what has already been mentioned about biomechanical changes , on high energy injuries it is of capital importance to check for associate neurovascular injuries and for injuries of the other stabilizers , which , when neglected , they conduct to a failure treatment .
Semiology
The first step to evaluate the patient is the clinical history . It must be understood the circumstances , the timing and the mechanism of the injury , characterize the signs and symptoms and make an assessment of the patient ’ s profile and of
Imaging
The radiographic study in posterioranterior profile views should be performed to exclude the existence of fractures and degenerative changes . The extra-long X-ray of the lower limbs has to be performed for the identification of axial deviations .
The evidence has given more and more strength to the stress X-ray , being considered the most accurate and reproducible methods in the study of tibiofemoral translation . 5 , 24-29 These should be carried out bilaterally with the application to the knee of a force of about 89-N directed : varus / valgus at 20 ° flexion ; posterior with the knee flexed at 90 ° flexion in neutral rotation and with relaxed quadriceps . The degree of posterior translation allows the classification of the injury :
• Partial : < 8 mm ( grade I )
• Complete isolated : 8-12mm ( grade II : 8-10mm ; grade III : 10-12mm )
• Associated with the LPC : > 12mm . The MRI study is indispensable ,
28 may 2018 www . revdesportiva . pt
the sport and labor activity. Usually, symptoms are subtle, with a feeling of discomfort or pain in the posterior face of the flexed knee and slight swelling, even in acute injury. In chronic cases, they may experience irradiation of the pain to the ante- rior face of the knee and when going down the stairs, walk in inclined planes or when they slowdown. 6 Physical examination must be tested for all ligament and meniscus structures. To look for the injury of the PCL, the most commonly tests are: • Posterior sag sign • Quadriceps activation test • Rear drawer • Reverse pivot shift • Dial test at 30° and 90° of knee flexion • External rotation recurvatum test. In cases of a chronic injury, the gait may undergo changes with the attenuation of the PCL structures, characterized by external rotation, posterolateral deviation and hyper- extension (varus thrust). There are devices, like arthrometer, that can be used, but the evidence has shown that it underestimates the posterior translation. 23,24 Imaging and PCL become the main rotational stabilizers, which leads to an exces- sive load on these structures. On the other hand, untreated chronic PCL or ACL injuries may cause attenua- tion of the remaining knee stabiliz- ers. In this way, it must be known that the normal biomechanics of the knee comes from a synergy between the static and the dynamic stabilizer structures and that the rupture of the PCL will have influence on the kinematics of the knee, causing posterior subluxation of the tibia, with increased contact forces in the medial and patellofemoral compart- ment, and ac ѥمѥ̈́)ѽ䁵͵́ѡɍ԰ذ+$ḾɅյ聵ɔ)ݥѠд)хȁݥѠɕѕͥ)ٕ+$Ìܔ聡ɝ)ѕͽѕݥѠձѤ)хɥ̸)QѼͥɅѥݡ)́ɕ䁉ѥ)̰)ɝ䁥ɥ́Ё́хȴ)хѼȁͽєɼ)م͍ձȁɥ́ȁɥ́)ѡѡȁх̰ݡݡ)ѕѡ䁍ՍЁѼɔ)ɕѵи)M)䁅ѡͥ)Qɔ́Դ)Ёɥ́ѡɔ)Ʌɕ䁅ͽѕ䰁ͼ)ѕݥѠ䔁A1 ɥ̸Դ܁%)ɥ͕́(ܹɕّѥل)QЁѕѼمՅєѡѥ)́ѡѽ丁%ЁЁ)չѽѡɍյх̰ѡ)ѥѡʹѡ)䰁Ʌѕɥ锁ѡͥ́)ѽ̴͕́)Ёѡѥӊéɽ)QɅɅՑ䁥ѕɥȴ)ѕɥȁɽ٥́͡ձȴ)ɵѼ፱Ցѡѕ)Ʌɕ́Ʌѥ̸ٔ)QɄ`Ʌ䁽ѡݕ)́́Ѽəɵȁѡ)ѥѥ᥅٥ѥ̸)Q٥ٕ́ɔ)ɔɕѠѼѡɕ́`Ʌ)ͥɕѡЁԴ)ɅєɕɽՍѡ́)ѡՑ䁽ѥɅɅͱ)ѥ԰дQ͔͡ձɥ)ЁѕɅݥѠѡѥ)ѼѡɍЀ8)ɕѕم̽م́Ѐ ᥽)ѕɥȁݥѠѡᕐЀ )᥽ɅɽхѥݥѠ)ɕᕐՅɥ̸Qɕ)ѕɥȁɅͱѥ́ѡ̴)ͥѥѡ+$AѥɅ$+$ єͽѕɵɅ)%$쁝Ʌ%%$ɵ+$ͽѕݥѠѡ1A ɵ)Q5I$Ց䁥́ͅ