Additional Case 1. Presentation to GP. David, 21, apprentice plumber R leg injury during rugby game (last pm) Hit from R side during tackle Impact on upper outside 1/3 of leg (foot planted on ground) No previous Hx of knee injuries No PMH of note. Review the anatomy of the knee.
David, 21, apprentice plumber
R leg injury during rugby game (last pm)
Hit from R side during tackle
Impact on upper outside 1/3 of leg (foot planted on ground)
No previous Hx of knee injuries
No PMH of note
makes up the joint capsule on either side of the patella; maintains patella alignment
contribute to stability when standing (this is when they are taut) are also ‘check’ ligaments for flexed rotation (permit but limit rotation)
Oblique popliteal ligament:
reinforces the joint capsule posteriorly
strengthens the joint capsule posterolaterally
Anterior cruciate ligament:
limits posterior rolling of the femoral condyles on the tibial plateau during flexion; prevents posterior displacement of the femur on the tibia and hyperextension of the knee joint
Posterior cruciate ligament:
limits anterior rolling of the femur on the tibial plateau during extension; also prevents anterior displacement of the femur on the tibia and helps prevent hyperflexion of the knee joint.
Medial collateral ligament tear
Non-contact change of direction; hyperextension on landing from a jump or; direct valgus force
Contact injury to the ground or; clash of knees
Contact valgus injury
Twisting on a planted foot
Positive swipe test
Tenderness along the subcutaneous border of the fibula (around the area he identifies as the impact site)
Grade 3 laxity with valgus stress
Lachman’s Test and anterior draw are inhibited by pain from David
Tell David he has injured a major knee ligament and that the pain is from local bruising
Knee splint + crutches
Refer for physiotherapy rehab and advice on weight bearing/return to work+sport
Source: Angus Hann
With Ligament testing you assess symptom response ( pain), laxity and end feel. Acute spasm will guard the joint and give u a false negative on Ligament testing.
Inhibition affects strength. May be unable to straight leg raise. Pain causes reflexive inhibition and may cause knee to give way. Need to encourage patient to relax when testing. Acute knee difficult.
3. What could be done to improve your confidence in the Lachman's and anterior draw test in this case?
4. What happens to the quadriceps muscle group with knee injury and splinting, does it matter? - what proactive measures may limit or prevent this?
The following week you are surprised to see David represent with a letter from the physio agreeing with your diagnosis about the knee injury, but expressing concern about the cause of the ongoing leg pain.
Repeat clinical examination shows a large effusion and there is laxity with Lachman's test.
You refer David for an x-ray which is shown below.
Femortibial joint space
hyper-extension lateral view allows assessment of slope of intercondylar roof in relation to the tibial plateau;
Plain radiographs cannot be used to diagnose ACL tears. In some cases, an avulsion fracture of the anterolateraltibial plateau (ie, Segond fracture) is identified at the site of attachment of the lateral capsular ligament.
The impact was on the upper outside one third of the leg while his foot was planted on the ground.
landing from a jump
A blow to the side of the knee, which can occur during a football tackle, may result in an ACL tear.
Coming to a quick stop, combined with a direction change while running, pivoting, landing from a jump, or overextending the knee joint (called hyperextended knee), also can cause injury to the ACL.
Basketball, football, soccer, and skiing are common causes of ACL tears
The ACL infrequently ruptures in children. Rather the bone on either end comes off.
Depends on activity level of patient
Long term sequelae include instability, particularly with pivoting type sports, but even walking
Instability causes damage to the menisci and the other ligaments