Degenerative changes in the
knee 2 years after anterior cruciate ligament rupture and related risk factors:
a prospective observational follow-up study.

Van Meer
BL, Oei EHG, Meuffels DE, van Arkel ERA, Verhaar JAN, Bierma-Zeinstra SMA, and
Reijman M. Am J Sports Med. 2016.
[Epub Ahead of Print].

Take Home Message: Among 143 people with an anterior
cruciate ligament (ACL) rupture, 40% had worsening osteophytes or cartilage
defects during the first 2 years after injury. Males and people with a meniscal
tear, medial cartilage defect at baseline, or medial bone marrow lesion at 1-year
follow-up may be at risk for these early structural changes.

Sports Med Res has summarized several studies reporting that
an athlete is at increased risk for knee osteoarthritis after an anterior
cruciate ligament (ACL) injury. Unfortunately, we still need a deeper
understanding of the early structural changes to design effective screening
tools and interventions. Therefore, van Meer and colleagues completed a prospective
cohort study to identify which factors are related with early (2 years post-surgery)
structural changes as assessed by magnetic resonance imaging (MRI). A total of
143 patients (18-45 years of age, 49 females) with a diagnosed ACL rupture completed
the study. At baseline (within 6 months of injury), 1 year, and 2 years post
injury participants completed questionnaires and received a physical
examination. Participants completed questionnaires to assess patient
characteristics, activity level, and frequency of giving away. Participants
underwent MRI at baseline, 1 year, and 2 years post injury to assess cartilage
defects, joint effusion, presence of bone marrow lesions, and meniscal tears,
progression of cartilage defects, and progression of osteophytes. During the
2-year follow-up period, 40% of participants had progression of cartilage
defects and/or osteophytes. The authors noted that physical activity level,
episodes of giving way during the first year, and treatment strategy (surgery,
delayed surgery, conservative care) were unrelated to structural changes. The
authors found 4 determinants of worsening cartilage defects:
1. male sex
(4.4 times more likely to have worsening)
2. medial cartilage
defects at baseline (3.7 times more likely to have worsening)
3. presence
of a medial bone marrow lesion at 1-year follow-up (5.2 times more likely to
have worsening)
4. presence
of a meniscal tears (6.4 times more likely to have worsening)

Overall, this study
provides clinicians with further insight into the connection between ACL
rupture and early structural changes that may precede osteoarthritis. However,
it is important to recognize that we are unsure about how many people who had
worsening cartilage defects will develop symptomatic knee osteoarthritis.
Regardless, clinicians should be aware of these risk factors because they may help
us screen patients who are high risk and may need to be educated about their
risk and advised to seek early care or increased screening. Furthermore, these
predictive factors may also be used for targeting future pharmacological and rehabilitative
treatment options. Future research may also clarify if baseline and 1 year
follow-up MRIs may be valuable. For example, post-traumatic bone marrow lesions
usually resolve within the first 12 months. However, patients who have a medial
bone marrow lesion at 12 months may be more likely to have cartilage loss
during the first 2 years after injury. Until more research can be completed,
clinicians should recognize that male patients or patients with meniscal tears
or cartilage defects at baseline might be at greater risk for cartilage loss
over the next 2 years. Clinicians should educate these patients about their
risk and steps they can take to reduce the risk for joint symptoms and
osteoarthritis (e.g., weight management, adopting strategies to prevent future

for Discussion
: Do you discuss the long-term implications of injury with your
patients? If so, are your patients are receptive to this counseling?

Written by: Kyle Harris
Reviewed by:  Jeffrey Driban

Related Posts:

van Meer, B., Oei, E., Meuffels, D., van Arkel, E., Verhaar, J., Bierma-Zeinstra, S., & Reijman, M. (2016). Degenerative Changes in the Knee 2 Years After Anterior Cruciate Ligament Rupture and Related Risk Factors: A Prospective Observational Follow-up Study The American Journal of Sports Medicine, 44 (6), 1524-1533 DOI: 10.1177/0363546516631936