title: Anterior cruciate ligament injury: post-traumatic bone marrow oedema correlates with long-term prognosis.
abstract: OBJECTIVE
  Bone marrow oedema (BME) in the knee is a feature of several pathological conditions, and it has been described with high frequency in patients with acute anterior cruciate ligament (ACL) injury. The aim of this study is to evaluate the significance of BME, assessed in MRIs performed for ACL injury, with regards to clinical outcome and return to sport.
  
  
  METHODS
  A total of 134 patients (98 men, 36 women) with ACL tear and MRI knee scan within six months from trauma were analysed. The presence of BME was evaluated on MRI images considering: extension and hyperintensity, the WORMS score oedema classification, and measuring the BME area. The clinical results were documented by IKDC-subjective score and the sport activity level by Tegner score at a minimum of five years follow up.
  
  
  RESULTS
  BME was present in 74 knees (55.2 %), with a mean area of 523 ± 370 mm². The presence of BME showed a gradual decrease over time (p = 0.008), being detectable in MRIs performed more than three months after trauma in just 25.0 % of cases. Although 54 % of the patients without BME after three months returned to their previous sport level, no patients with oedema reached a full sport recovery (p = 0.01). In the group that underwent ACL reconstruction, the BME area was significantly correlated with a return to the previous sport level at the mid/long-term follow-up (p = 0.038).
  
  
  CONCLUSIONS
  BME is a common finding, which decreases over time after injury. However, when BME is still detectable it correlates with clinical prognosis, and even in sport-active patients undergoing ACL reconstruction, a higher BME area is a negative predictive factor for a successful outcome at the mid/long-term follow-up.
authors: II Orthopaedic and Traumatologic Clinic-Biomechanics and Technology Innovation Laboratory, Rizzoli Orthopaedic Institute, Via Di Barbiano, 1/10, 40136, Bologna, Italy.
authors: Giuseppe
authors: G
authors: Filardo
authors: Nano-Biotechnology Laboratory, Rizzoli Orthopaedic Institute, Bologna, Italy.
authors: Elizaveta
authors: E
authors: Kon
authors: II Orthopaedic and Traumatologic Clinic-Biomechanics and Technology Innovation Laboratory, Rizzoli Orthopaedic Institute, Via Di Barbiano, 1/10, 40136, Bologna, Italy.
authors: Francesco
authors: F
authors: Tentoni
authors: II Orthopaedic and Traumatologic Clinic-Biomechanics and Technology Innovation Laboratory, Rizzoli Orthopaedic Institute, Via Di Barbiano, 1/10, 40136, Bologna, Italy.
authors: Luca
authors: L
authors: Andriolo
authors: II Orthopaedic and Traumatologic Clinic-Biomechanics and Technology Innovation Laboratory, Rizzoli Orthopaedic Institute, Via Di Barbiano, 1/10, 40136, Bologna, Italy.
authors: Alessandro
authors: A
authors: Di Martino
authors: Radiology and Diagnostic Imaging Department, Rizzoli Orthopaedic Institute, Bologna, Italy.
authors: Maurizio
authors: M
authors: Busacca
authors: II Orthopaedic and Traumatologic Clinic-Biomechanics and Technology Innovation Laboratory, Rizzoli Orthopaedic Institute, Via Di Barbiano, 1/10, 40136, Bologna, Italy. berardo.dimatteo@gmail.com.
authors: Berardo
authors: B
authors: Di Matteo
authors: II Orthopaedic and Traumatologic Clinic-Biomechanics and Technology Innovation Laboratory, Rizzoli Orthopaedic Institute, Via Di Barbiano, 1/10, 40136, Bologna, Italy.
authors: Maurilio
authors: M
authors: Marcacci
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods; D001855:Bone Marrow Diseases / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D004487:Edema / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D007719:Knee Joint / Q000473:pathology* / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D055815:Young Adult
keywords: ACL injury; Bone marrow edema; MRI; Prognosis; Return to sport
references: Int Orthop. 2013 Feb;37(2):311-20
references: 23207581
references: Knee Surg Sports Traumatol Arthrosc. 2008 Mar;16(3):270-4
references: 18074118
references: Am J Sports Med. 1998 Jan-Feb;26(1):15-9
references: 9474396
references: Int Orthop. 2013 Feb;37(2):271-7
references: 22941098
references: Int Orthop. 2011 Aug;35(8):1251-6
references: 21340682
references: Int Orthop. 2013 Nov;37(11):2265-9
references: 23995333
references: Am J Sports Med. 2000 Mar-Apr;28(2):152-5
references: 10750989
references: Int Orthop. 2013 Feb;37(2):279-84
references: 23307016
references: Clin Radiol. 2004 May;59(5):439-45
references: 15081849
references: J Bone Joint Surg Am. 2011 Aug 17;93(16):1510-8
references: 22204006
references: Am J Sports Med. 2008 Apr;36(4):671-7
references: 18326830
references: Br J Sports Med. 2004 Oct;38(5):592-6
references: 15388546
references: Arthroscopy. 2001 May;17 (5):445-9
references: 11337710
references: Arthroscopy. 2011 Jan;27(1):65-76
references: 21035995
references: Knee Surg Sports Traumatol Arthrosc. 2014 Sep;22(9):2181-6
references: 24002525
references: Eur J Orthop Surg Traumatol. 2014 Dec;24(8):1481-7
references: 24057340
references: Arthroscopy. 1994 Aug;10 (4):453-60
references: 7945643
references: Am J Sports Med. 2008 May;36(5):927-33
references: 18354139
references: Am J Sports Med. 2012 Feb;40(2):276-85
references: 21952715
references: Am J Sports Med. 2010 Sep;38(9):1778-87
references: 20595556
references: Int Orthop. 2013 Feb;37(2):285-90
references: 23138966
references: Arthroscopy. 1991;7(1):45-51
references: 2009119
references: Int Orthop. 2013 May;37(5):809-17
references: 23377111
references: Scand J Med Sci Sports. 2012 Oct;22(5):635-42
references: 21477165
references: Clin Radiol. 2005 Jun;60(6):627-36
references: 16038689
references: Radiographics. 2000 Oct;20 Spec No:S135-51
references: 11046168
references: Am J Sports Med. 1992 Jul-Aug;20(4):382-9
references: 1415878
references: Knee Surg Sports Traumatol Arthrosc. 2002 Mar;10(2):96-101
references: 11914767
references: Am J Sports Med. 2013 Aug;41(8):1801-7
references: 23744907
references: Int Orthop. 2011 Jul;35(7):1093-7
references: 21287172
references: Int Orthop. 2012 Jan;36(1):171-7
references: 21898038
references: Int Orthop. 2013 Feb;37(2):201-6
references: 22782378
references: Vojnosanit Pregl. 2011 Sep;68(9):762-6
references: 22046881
references: Am J Sports Med. 1999 Jul-Aug;27(4):489-94
references: 10424219