Histopathological changes in the human posterior cruciate ligament during aging and osteoarthritis: correlations with anterior cruciate ligament and cartilage changes

Abstract

Objectives-To determine the histological patterns of posterior cruciate ligament (PCL) degeneration during aging and in relation to changes in articular cartilage and anterior cruciate ligament (ACL) across the entire adult age spectrum.Methods-Human knee joints (n=120 from 65 donors) were processed within 72 hours postmortem. Articular cartilage surfaces were graded macroscopically. Each PCL was histologically evaluated for inflammation, mucinous changes, chondroid metaplasia, cystic changes and orientation of collagen fibers. Severity of PCL degeneration was classified as normal, mild, moderate or severe. PCL scores were compared to ACL and cartilage scores from the same knees.Results-All knees had intact PCL. Histologically, 6% were normal, 76% showed mild, 12% moderate and 9% severe degeneration. Fiber disorientation was the most prevalent and severe change. Histological grades of PCL and ACL correlated but significantly fewer PCL than ACL showed severe changes. There was weaker correlation between aging and total histological PCL scores (R=0.26) compared to aging and ACL scores (R=0.42). ACL scores correlated with cartilage scores (R=0.54) while PCL scores increased with severity of OA from grades 0 to III but not between OA grades III to IV (R=0.32). In knees with ruptured ACL, the PCL scores correlated with cartilage scores of the lateral compartment.Conclusions-PCL histopathological changes are less severe than in the ACL. PCL degeneration was associated with ACL and cartilage damage. The lack of correlation with age indicates independent pathways for PCL versus ACL degeneration.

Meniscal and ligament modifications in spontaneous and post-traumatic mouse models of osteoarthritis

“…The pathological chondrogenesis of ligaments described in mouse knee joints in this study also shows many similarities to human joints [44,45]. It has been found that human cruciate ligaments from OA patients show important chondroid and cartilage metaplasia, which involve a change in ligament cell phenotype to a more chondrocyte-like round cell morphologies [34,46]. This included positive Col2…”

Post-Traumatic Osteoarthritis in Mice Following Mechanical Injury to the Synovial Joint

“…Although there were subtle differences in meniscus pathology across loading groups and time points, our findings of meniscus and PCL pathology in the mouse were consistent with the observations that they are associated with cartilage damage and OA in humans343536. Additionally, our findings of gradual increase in osteophyte count over time (especially in 12N group) in loaded knees is consistent with another study of ACL transection in mice37.…”

Aging processes and the development of osteoarthritis

“…In addition to aging studies in the human meniscus, the anterior [10••] and posterior[11] cruciate ligaments (ACL and PCL respectively) have also been studied. Similar to the meniscus work noted above by Pauli et al[7••], the same group used human donor tissue and compared changes in the ACL and PCL to those in cartilage from the same joints.…”