Repair of Osteochondral Lesions - Engineered Bone: Tissue Engineering Intelligence Unit - page 178

Assessment of Clinical Outcome
To validate the efficacy of cartilage repair procedures in clinical settings and compare results
from different methods, it will be necessary to perform rigorous controlled and randomised
trials with stringent evaluation of the outcomes. Assessments should include (i) parameters
related to the clinical status of the patient, (ii) radiographic findings and histological analyses of
biopsies at the site of repair, (iii) biochemical assays to quantify the fractions of different col-
lagen types in a small biopsy, 22 and (iv) measurement of cartilage physical properties, possibly
using minimally invasive techniques. 121,122 The International Cartilage Repair Society (ICRS)
has proposed a standard Cartilage Injury Evaluation Package (www.cartilage.org/
ICRS_Evaluation.pdf ), consisting of a self-assessment questionnaire for the patient, clinical
evaluation forms and a histological grading system for cartilage biopsies. Standardised compi-
lation of data at defined times after surgery will allow more objective patient evaluation, even if
gathered by different surgeons.
The increasing number of groups/companies offering a cell-based cartilage repair product
introduces the need to assess clinical outcome in patients grouped not only according to repair
procedure, but also to the specific product used within a certain treatment concept. Objective
comparison of different repair methods can be facilitated by the introduction of databases
where standardised evaluation of patients treated with a specific product can be recorded.
Considering that the “success” of any procedure aimed at repairing cartilage injuries can
only be quantified as the durability of a pain-free and functional joint, observation time in
clinical trials should be extended for several years before any conclusion can be drawn. Since
this fact represents a major obstacle in comparing different treatments within a reasonable time
frame, strong emphasis should be put in the identification of “early predictors” of long-term
outcomes, in order to allow establishment of shorter but equally relevant clinical trials.
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