The document discusses management and understanding of knee injuries, particularly focusing on ACL injuries, and emphasizes that most knee injuries do not require surgery and can improve with appropriate physiotherapy. It outlines the importance of prompt diagnosis and rehabilitation, including exercises to restore knee function, while noting that surgical intervention is not always urgent. Additionally, it questions the efficacy of ACL reconstruction in preventing osteoarthritis, suggesting that non-operative management may be adequate in certain cases.

1. University of Chester
MSc Sports Medicine
Sports Knee
ACL Injuries
Chester, 14th March 2024
Prof Vladimir Bobić MD FRCSEd
Consultant Orthopaedic Knee Surgeon
Chester Knee Clinic
at Nuf
fi
eld Health, the Grosvenor Hospital Chester
www.kneeclinic.info
@ChesterKnee

2. Chester Knee Clinic www.kneeclinic.info office@kneeclinic.info @ChesterKnee

3. Disclaimer

5. Basic Knee Anatomy

6. Sport Knee Problems and Injuries
❖ The Good News:
❖ Most knee injuries do not require surgery!
❖ Most knee problems will get better, given a few
weeks and appropriate physiotherapy.
❖ The Bad News:
❖ Most knee injuries will take time (usually more
than expected) to get better.
❖ It may take weeks or even months before you are
back to your pre-injury levels.

7. Who Needs Doctors (and Surgeons?)!
Skiing Knee Injuries
• Most serious knee injuries are very
painful initially.
• Some injuries, often caused by
deceleration and change of
direction, not necessarily at high
speed, are followed by a loud "pop"
or "crack" and rapid effusion,
mainly because of ACL injury and
bleeding inside the joint.
• If you knee is painful, especially if
you cannot bear weight after the
injury, it is always a good idea to
have an X-ray of your knee and leg,
as soon as possible, to exclude
clinically less obvious minimally
displaced or non-displaced bone
fractures and fissures.
• If your bones are not broken, which
is most likely, generally there is no
panic about any surgical
intervention, even if you have a
major ligament injury …
29

8. Sports Knee Injuries
• … the best course of action is to calm down,
ice the knee, get a compressive knee sleeve
or a brace (but do not immobilise the knee in
full extension), take some painkillers and have
a rest.
• If the knee is swollen, the most comfortable
position is at approximately 30 degrees of
flexion, or in semi-flexion.
• If your knee is still swollen and painful
(especially on bearing weight) the following
day, and if it feels unstable, consider seeing a
knee specialist and having an MRI scan.
8

9. Sports Knee Injuries
• If the knee remains locked it is
likely that you have developed a
displaced meniscal tear, which
may require arthroscopic
surgery.
• Sometimes femoral avulsion of
the ACL will cause loss of
extension as torn and swollen
ligament impinges on the
anterior intercondylar femoral
notch.
• A torn medial collateral
ligament (MCL) will heal and
remodel very well on its own most
of the time, except in extensive
multi-ligament knee injuries.
9

10. Sports Knee Injuries
• Acute ACL injury may require
surgery but generally there is no
rush.
• The most important thing is to get
the knee going with appropriate
exercises and to re-assess the
damage clinically, and if necessary,
with further more specific MR
imaging studies.
• In any case, you should aim to
regain full knee extension as
soon as possible, before the soft
tissues and muscles at the back
of the knee start getting tight.
• Getting rid of swelling and
restoring a full range of movement
and muscle power are the main
goals during the first 2 to 4 weeks
following a knee injury.
10

11. ACL Injuries
• An experienced clinician can
diagnose as many as 90% of
ACL tears based on history and
clinical examination, but ACL
injuries are still often missed.
• Clinical diagnosis of a complete
acute ACL tear is relatively
straightforward, although
swelling, pain, limited range of
knee movement and associated
injuries (mainly of the MCL and
the medial meniscus) complicate
this issue.
• Clinical tests, including the
Lachman's test, anterior
drawer and pivot shift are often
suggestive of a major ACL tear,
especially if associated with
symptoms of giving way and
knee instability.
11

12. ACL Injuries
• Clinical examination may be difficult in large patients, in patients
with strong secondary muscular restraints, and in patients with
an acute injury and soft tissue swelling and guarding.
• Partial ACL tears are especially difficult to diagnose clinically,
although MR imaging is quite accurate.
• Some ACL deficient knees are initially stable clinically and
remain stable and symptom-free, especially if the MCL and both
menisci are intact, and while the patient's activity levels remain
reduced.
• ACL reconstruction is not an emergency operation!
• Delaying surgery until swelling goes down and a full
range of motion is obtained significantly reduces the
chance of having problems post-operatively.
• Delaying acute surgery also allows the patient to be
mentally better prepared for surgery and gives the
patient time to learn, fully understand and practise
adequate exercises.
• Early rehabilitation, with emphasis on proprioceptive
exercises, is of paramount importance.
12

13. Source: Dr David Ritchie, Glasgow

14. Acute ACL injury with extensive lateral bone bruising
CKC UK
MRI 110206: “Recent full thickness tears of both cruciate ligaments with marrow oedema beneath the posterior
intercondylar eminence. In the lateral compartment, localised bone bruising over the posterior aspect of
the lateral tibial condyle and anterior aspect of the lateral femoral condyle.” Dr D Ritchie, Glasgow.
CKC MRI 110206 CKC MRI 110206
14

15. ACL injury + extensive BB
CKC MRI 110206
7 months later

16. Source: Dr David Ritchie, Glasgow

17. Conclusion:
A majority of
acutely ACL injured
knees (92%) had a
cortical depression
fracture, which was
associated with
larger BML volumes.
This indicates
strong compressive
forces to the
articular cartilage
at the time of
injury, which may
constitute an
additional risk
factor for later knee
OA development.
50

18. Source: Dr David Ritchie, Glasgow

21. ACL Reconstruction with BPTB autograft

22. ACL Reconstruction with BPTB autograft
and reservable interference screws

23. ACL Injury and Recon Rehab

25. ACL Repair

30. Long Term ACL Deficiency

33. “… convincing evidence
is still lacking for the
superiority of ACL
reconstruction to non-
operative management
in terms of the
incidence of PTOA …”

34. ACL Reconstruction and OA
Conclusions: The current literature does not provide substantial
evidence to suggest that ACL Reconstruction is an adequate
intervention to prevent knee osteoarthritis.
With regard to osteoarthritis prevalence, the only patients benefiting
from ACLR were those undergoing concomitant meniscectomy with
reconstruction.
Luc B, et al. J Athl Train. 2014 Sep 18.
?

35. Long Term ACL Deficiency

36. Mucoid ACL Degeneration, ACL
Ganglions & Subchondral Cysts
(an update from ACL SG Åre, Sweden, 2016)
Vladimir Bobić, MD, FRCSEd
Consultant Orthopaedic Knee Surgeon
Chester Knee Clinic, Chester, UK
ACL Study Group 2023
St Kitts, 29th January to 2nd February 2023

37. Chronic ACL Deficiency

39. Cross-talk Between Articular Cartilage,
Subchondral Bone and ACL
• Our focus now is on the role of enthesitis which seems to be the key to the start of the
inflammatory and subsequently degenerative processes of the ACL.
• MRI analyses indicates that the localization of bone marrow oedema in early OA is
often associated with ligament attachment site, the enthesis, which seems to play a
central role.
• The intimate cross-talk between synovitis, articular cartilage, ACL and
subchondral bone is no doubt the main feature of MDACL.
• The aetiology is also suggestive of disrupted neuromuscular network and joint
homeostasis at several intra-articular levels.
CKC UK

40. Articular cartilage + Subchondral plate + Trabecualar bone are
biologically and functionally inseparable OsteoChondral unit
which absorbs and distributes loads across the joint.
CKC UK

42. Quantitative MRI (qMRI) and in vivo
deformational behaviour of articular cartilage
• One of the great advantages of
MRI, in comparison with histology,
is that consecutive slices are
contiguous and spatially aligned so
that 3D parameter can be
obtained.
• These parameters include
cartilage volume, thickness,
surface and curvature.
• Current findings suggest that
human cartilage deforms very
little in vivo during
physiological activities and
recovers from deformation
within 90 min after loading, but
physical training status does not
seem to affect in vivo
deformational behaviour.
Eckstein F, Hudelmaier M, Putz R: The effects of
exercise on human articular cartilage. J Anat 2006
(Anatomical Society of Great Britain and Ireland);
208: 491-512.

43. Eckstein F, et al:
The effects of exercise on human
articular cartilage.
J Anat 2006; 208: 491-512.
Quantitative MRI (qMRI)
and in vivo
deformational behaviour
of articular cartilage

46. So, what is the best treatment option?
Well, exercise, train, enjoy your sports but be
realistic and do your best to prevent ACL injury!

47. THANK YOU FOR YOUR ATTENTION
KEEP MOVING AND LOOK AFTERYOUR KNEES!