Here is the design of a clinical trial:

Official Title: Randomized Controlled Trial Comparing Clinical Outcomes of Instant MSC Product Accompanying Autologous Chondron Transplantation (IMPACT) for Focal Articular Cartilage Lesions of the Knee to Conservative Treatment

Included conditions:
- Cartilage Damage

Study Armgroups:
- {'label': 'IMPACT', 'type': 'EXPERIMENTAL', 'description': "Application of a mixture of allogenic MSC's and autologous chondrons with a fibrin cell carrier (Tisseel®) during one surgical procedure.", 'interventionNames': ['Drug: Instant MSC Product accompanying Autologous Chondron Transplantation']}
- {'label': 'Control', 'type': 'NO_INTERVENTION', 'description': "Optional physical therapy or pain medication, according to participants' desire for 9 months."}

Interventions:
- {'type': 'DRUG', 'name': 'Instant MSC Product accompanying Autologous Chondron Transplantation', 'description': "Application of a mixture of allogenic MSC's and autologous chondrons with a fibrin cell carrier (Tisseel®) in the cartilage defect of the knee during one surgical procedure.", 'armGroupLabels': ['IMPACT']}

Primary Outcomes:
- {'measure': 'Clinical change on scale of 0-100', 'description': 'KOOS-questionnaire (Knee injury and Osteoarthritis Outcome Score, 100 indicating no symptoms and 0 indicating extreme symptoms)', 'timeFrame': 'At baseline, 3, 6 and 9 months'}
- {'measure': 'Quality of life change on scale of 0-100', 'description': "EQ-5d-questionnaire (The EQ-5D-5L has 5 dimensions, each dimension has 5 levels: no problems, slight problems, moderate problems, severe problems and extreme problems. The EQ VAS records the patient's self-rated health on a vertical visual analogue scale, where the endpoints are labelled 'The best health you can imagine' and 'The worst health you can imagine'. The VAS can be used as a quantitative measure of health outcome that reflect the patient's own judgement.)", 'timeFrame': 'At baseline, 3, 6 and 9 months'}

Please estimate the sample size based on the assumption: 
Power of 0.8, alpha of 0.05, potential loss to follow-up
Sample size {14}
        The sample size was calculated for the primary objective (treatment effect up to 9Â months postoperatively) based on the Hotelling-Lawley trace [24, 25]. Based on a standard deviation of 15 [23], correlation of the repeated measures of 0.7 (data from our phase I trial [21]), and with a power of 0.8 and alpha of 0.05, a minimum of 44 patients should be included to detect a minimal clinical relevant treatment effect of 10 for KOOS [23]. To account for potential loss to follow-up, and uncertainties in the correlation pattern and standard deviation for nonsurgical treatment, this was rounded up to 60 patients in total.