Date Published: June 12, 2018
Publisher: Public Library of Science
Author(s): Simon Décary, Michel Fallaha, Sylvain Belzile, Johanne Martel-Pelletier, Jean-Pierre Pelletier, Debbie Feldman, Marie-Pierre Sylvestre, Pascal-André Vendittoli, François Desmeules, Kirill Gromov.
To assess the diagnostic validity of clusters combining history elements and physical examination tests to diagnose partial or complete anterior cruciate ligament (ACL) tears.
Prospective diagnostic study.
Orthopaedic clinics (n = 2), family medicine clinics (n = 2) and community-dwelling.
Consecutive patients with a knee complaint (n = 279) and consulting one of the participating orthopaedic surgeons (n = 3) or sport medicine physicians (n = 2).
History elements and physical examination tests performed independently were compared to the reference standard: an expert physicians’ composite diagnosis including history elements, physical tests and confirmatory magnetic resonance imaging. Penalized logistic regression (LASSO) was used to identify history elements and physical examination tests associated with the diagnosis of ACL tear and recursive partitioning was used to develop diagnostic clusters. Diagnostic accuracy measures including sensitivity (Se), specificity (Sp), predictive values and positive and negative likelihood ratios (LR+/-) with associated 95% confidence intervals (CI) were calculated.
Forty-three individuals received a diagnosis of partial or complete ACL tear (15.4% of total cohort). The Lachman test alone was able to diagnose partial or complete ACL tears (LR+: 38.4; 95%CI: 16.0–92.5). Combining a history of trauma during a pivot with a “popping” sensation also reached a high diagnostic validity for partial or complete tears (LR+: 9.8; 95%CI: 5.6–17.3). Combining a history of trauma during a pivot, immediate effusion after trauma and a positive Lachman test was able to identify individuals with a complete ACL tear (LR+: 17.5; 95%CI: 9.8–31.5). Finally, combining a negative history of pivot or a negative popping sensation during trauma with a negative Lachman or pivot shift test was able to exclude both partial or complete ACL tears (LR-: 0.08; 95%CI: 0.03–0.24).
Diagnostic clusters combining history elements and physical examination tests can support the differential diagnosis of ACL tears compared to various knee disorders.
The anterior cruciate ligament (ACL) is a major stabilizing structure of the knee against excessive anterior translation and internal rotation of the tibia [1, 2]. An ACL tear, either partial or complete, is a significant knee injury. The overall incidence rate in the general population varies between 30 to 80 per 100000 persons-years [3–5]. This injury is particularly common in younger individuals as it occurs approximately 70% of the time as a result of a trauma in a sporting activity requiring pivot such as football, soccer, basketball or alpine skiing [1, 5–7]. In the United States, this translate to about 250 000 ACL tears annually . Of these individuals, 50 to 75% will opt for an ACL reconstruction surgery which incurs costs of up to two billion dollars [1, 3, 5, 8].
Table 2 presents the characteristics of participants. A total of 279 individuals participated (96.2% of those recruited). Participants were diagnosed with 359 primary and secondary diagnoses as follows: knee osteoarthritis (n = 129), patellofemoral pain (n = 75), symptomatic meniscal tears (n = 80) or other knee diagnoses (n = 32). Forty-three individuals (15.4%) received a diagnosis of partial (n = 21) or complete (n = 22) anterior cruciate ligament (ACL) tear. Overall, individuals with an ACL tear were significantly younger (ACL: 38.6±12.9 years old, others: 51.0±15.6 years old, p<0.05) and had a lower body mass index (ACL: 26.9±5.8, others: 29.7±6.6, p<0.05) compared to those without an ACL tear. Most individuals with an ACL tear were recruited in the orthopaedic clinics (95.3%) and had an history of trauma as the reason for consultation. (79.1%). More individuals with an ACL tear had pain for less than 3 months (ACL: 23.3%, others: 10.2%, p<0.05) and more than half were referred to surgery after consultation (ACL: 53.5%, others: 10.6%, p<0.05). For complete ACL tears only, 95.4% of individuals had a history of trauma as the reason for consultation and 68.1% were referred to surgery after consultation. This study assessed the diagnostic validity of clusters combining history elements and physical examination tests to diagnose or exclude partial or complete ACL tears compared to other knee disorders. We first observed that when individually performed, the Lachman and the pivot shift tests reached substantial positive LR (LR+>10) to diagnose and moderate negative LR (LR- <0.2) to exclude partial or complete ACL tears . In the present cohort, this increased positive post-test probability by 72.6% and negative post-test probability by 12.4% and 10.4% for both tests. These results are comparable with data synthesized in a previous meta-analysis reporting substantial positive LR to diagnose a partial or complete ACL tear using these tests (Lachman: LR+ = 10.2 (95%CI: 4.6–22.7), pivot shift: LR+ = 12.0 (95%CI: 5.0–31.0)) and moderate negative LR to exclude an ACL tear (Lachman: LR- = 0.2 (95%CI: 0.10–0.30)) . Taken alone these tests can be considered clinically useful to diagnose or exclude a partial or complete ACL tear. We identified diagnostic clusters combining history elements and physical examination tests that can accurately support the differential diagnosis of partial or complete ACL tears compared to other knee disorders. Given adequate external validation and appropriate clinical training by clinicians, these clusters could be used by health providers involved in musculoskeletal care in settings with limited access to MRI and initiate an accelerated rehabilitation protocol or propose a specialty referral when surgery is considered. Source: http://doi.org/10.1371/journal.pone.0198797