## 6 Alternative Methods of Articular Cartilage Diagnosis
### Numerical Methods and Artificial Intelligence
Although individual methods differ in terms of clinical maturity, cost, diagnostic performance, and capacity to detect early degenerative changes, their complementary value should be emphasised. To facilitate a clearer understanding of the advantages and limitations of each modality, Table 5 provides a comparative overview of selected imaging and functional diagnostic techniques used in the assessment of articular cartilage. The comparison includes criteria such as diagnostic accuracy, invasiveness, operator dependence, clinical readiness, and ability to assess biomechanical or biochemical tissue properties. This synthetic summary may serve as a practical reference in clinical decision-making and future research planning. \begin{table}
\begin{tabular}{c c c} \hline
**Modality** & **Main Strengths** & **Key Limitations** \\ \hline T2/T1p/dGEMRIC MRI & Sensitive to biochemical changes; useful for early OA detection & Requires special protocols or contrast agents; expensive; time-consuming \\ \hline Ultrasound Elastography & Provides mechanical property estimates; fast & Surface-limited; low penetration; operator-dependent \\ \hline Vibroarthrography (VAG) & Functional, real-time mechanical assessment; simple setup & Low spatial specificity; experimental; signal variability \\ \hline OCT & Micron-level resolution; near-histological visualisation & Shallow penetration depth; limited to intra-articular or open procedures \\ \hline Raman Spectroscopy & Molecular composition profiling; high-free biochemical insights & Low depth penetration; motion sensitive; experimental \\ \hline Modal Analysis & Provides dynamic mechanical parameters; sensitive to tissue degradation & High experimental complexity; limited to research applications \\ \hline \end{tabular}
\end{table} 
Table 4: _Cont._ \begin{table}
\begin{tabular}{c c c c c c} \hline
**Modality** & **Diagnostic Accuracy** & **Invasiveness** & **Operator Dependence** & **Clinical Readiness** & **Ability to Assess Biomechanics** & **Other Notes** \\ \hline MRI & High for structure, moderate for early OA & Non-invasive & Low & Widely available & Indirect (via advanced protocols) & High cost; long exam duration; sensitive to motion artifacts \\ \hline CT-Arthrography & High for surface integrity & Minimally invasive (contrast + radiation) & Low & Available, especially when MRI is contraindicated & No & Risk of infection, allergic reaction; repeated use limited due to radiation \\ \hline \end{tabular}
\end{table} 
Table 5: Comparative analysis of alternative methods of articular cartilage diagnosis. In summary, alternative diagnostic methods of AC are an ever-evolving area of research aimed at the early detection of degenerative changes. The techniques discussed above show an increasingly precise view of the AC condition, taking into account the structural, biochemical and biomechanical aspects. Modern vibratory and quantitative imaging techniques enable the non-invasive identification of subtle changes in the composition and properties of AC, thus detecting pathological changes before morphologically visible symptoms of OA develop. A decrease in Young's modulus, disorganisation of collagen fibres, or an increase in permeability are directly reflected in the results obtained by a number of diagnostic techniques. An increase in T2 relaxation time, an increase in T1\(\rho\), or a decrease in dGEMRIC indices have been shown to be associated with a deterioration in the mechanical properties of AC [374; 375]. The use of advanced spectroscopic methods or