Checked: 17-10-2014 by
vicky.ryan Next Review: 21-10-2016
Knee injuries - assessment NS MOM
management of injuries arising from acute trauma to the knee joint, including:
initial assessment and radiologic investigations
soft tissue injuries
red flags and referral criteria
management of soft tissue injuries
Out of scope:
specific management of fractures and dislocations
management of crush injuries and traumatic amputation of the knee joint
Knee injuries :
muscle strain (or 'pull'):
stretching or tearing of muscle fibres
most strains happen because the muscle has:
been stretched beyond its limits; or
been forced to contract too strongly
graded depending on the severity of muscle fibre damage:
first-degree strain − mild strain when only a few muscle fibres are stretched or torn; injured muscle is tender and painful, but has normal strength
second-degree strain − moderate strain, with a greater number of injured fibres and more severe muscle pain and tenderness; swelling present and noticeable loss of strength, sometimes with visible bruising
third-degree strain − muscle is torn all the way through, sometimes producing a 'pop' sensation as the muscle rips into two separate pieces or shears away from its tendon; there is total loss of muscle function
knee ligament injuries :
stretching or tearing of the knee ligaments
can be graded by:
grade I – no increased laxity, pain and tenderness over the course of the ligament, no actual disruption of fibres
grade II – some increased laxity compared with the other knee, usually pain and tenderness over the course of the ligament, some disruption of the fibres
grade III – gross laxity, tenderness over the ligament may or may not be present as there are no 'intact' fibres to stress, complete rupture of the ligament
meniscal tears :
menisci are semi-lunar shaped discs of fibrocartilage located in the medial and lateral aspects of the knee joint, positioned between the articular surfaces of the tibia and femur
meniscal tears typically occur as a result of tibial rotation whilst the weight bearing knee is in flexion
may also occur through repetitive motion such as squatting
Map of Medicine is not responsible for the correctness or accuracy of any content uploaded, referred to or linked to from the system.
Efforts are made to ensure the accuracy and agreement of these guidelines. However, we cannot guarantee this. This guidance does not override the individual responsibility of healthcare professionals to make decisions appropriate to the circumstances of the individual patient, in consultation with the patient and/or guardian or carer, in accordance with the mental capacity act, and informed by the summary of product characteristics of any drugs they are considering. Practitioners are required to perform their duties in accordance with the law and their regulators and nothing in this guidance should be interpreted in a way that would be inconsistent with compliance with those duties
'Knee ligament tears' and 'Meniscal tears' have been incorporated into this care map, and updated with the following references:
 Paxton ES, Stock MV, Brophy RH. Meniscal repair versus partial meniscectomy: a systematic review comparing reoperation rates and clinical outcomes. Arthroscopy 2011; 27: 1275-88
 Elattar M, Dhollander A, Verdonk R et al. Twenty-six years of meniscal allograft transplantation: is it still experimental? A meta-analysis of 44 trials. Knee Surg Sports Traumatol Arthrosc 2011; 19: 147-57.
 Hergan D, Thut D, Sherman O et al. Meniscal allograft transplantation. Arthroscopy 2011; 27: 101-12.
 Delince P, Ghafil D. Anterior cruciate ligament tears: conservative or surgical treatment? A critical review of the literature. Knee Surg Sports Traumatol Arthrosc 2012; 20: 48-61.
 Biau DJ, Katsahian S, Dartus J. Patellar Tendon Versus Hamstring Tendon Autografts for Reconstructing the Anterior Cruciate Ligament: A Meta-Analysis Based on Individual Patient Data. Am J Sports Med 2009; 37: 2470-8.
 Raynor MC, Pietrobon R, Guller U et al. Cryotherapy after ACL reconstruction: a meta-analysis. J Knee Surg 2005; 18: 123-29.
 Harrison BK, Abell BE, Gibson TW. The Thessaly test for detection of meniscal tears: validation of a new physical examination technique for primary care medicine. Clin J Sport Med 2009; 19: 9-12.
 Karachalios T, Hantes M, Zibis AH et al. Diagnostic accuracy of a new clinical test (the Thessaly test) for early detection of meniscal tears. J Bone Joint Surg Am 2005; 87: 955-62.
 American College of Radiology (ACR). Acute trauma to the knee. VA: ACR; 2011.
 Linko E, Harilainen A, Malmivaara A et al. Surgical versus conservative interventions for anterior cruciate ligament ruptures in adults. Cochrane Database Syst Rev 2005; 18: CD001356.
 Forster MC, Forster IW. Patellar tendon or four-strand hamstring? A systematic review of autografts for anterior cruciate ligament reconstruction. Knee 2005; 12: 225-30.
 Grant JA, Tannenbaum E, Miller BS et al. Treatment of combined complete tears of the anterior cruciate and medial collateral ligaments. Arthroscopy 2012; 28: 110-22.
 National Institute for Health and Clinical Excellence (NICE). Partial replacement of the meniscus of the knee using a biodegradable scaffold. London: NICE; 2012.
Date of publication: 30-Apr-2012
This care map has been drafted using the Map of Medicine editorial methodology and represents best clinical practice according to the highest quality evidence available, including the following guidelines:
 PRODIGY. Sprains and strains. Version 1.4. Newcastle upon Tyne: PRODIGY; 2008.
 New Zealand Guidelines Group (NZGG). The diagnosis and management of soft tissue knee injuries: internal derangements. Wellington, NZ: NZGG; 2003.
Further information was provided by the following references including practice-based knowledge: [3-6].
The severity of symptoms and signs depends on the severity of the sprain, eg whether there has been a partial or complete ligament tear :
common symptoms and signs include:
tenderness and swelling
functional loss, eg pain on weight-bearing
mechanical instability (if the sprain is severe)
NB: Marked bruising and swelling may indicate a complete ligament tear or fracture .
The majority of diagnoses can be made or at least strongly suggested on the history alone :
mechanism of injury 
site and severity of pain 
inability to bear weight at time of injury 
confidence on twisting 
onset and extent of swelling 
lack of extension (locking) 
sense of disruption or something coming out of place 
popping sensation or sound 
tingling, numbness, or weakness distally 
previous episodes 
general health 
anticoagulant use 
Examination should be carried out with the patient relaxed in a semi-recumbent position on an examination couch; the injured knee must be examined from the side of the couch it lies on  − assess:
look − swelling, bruising, abrasions, scars 
feel − effusion, tenderness and its specific site, test sensation/circulation 
move − ability to extend knee passively and actively, range of flexion 
tests of stability (can be difficult/impossible in acutely injured knee) :