Background
The Missouri Osteochondral Preservation System (MOPS) is a novel medium designed to increase the viability of donor tissue cells beyond the typical 14-day period of fresh graft storage (4°C) medium that is the standard of care for osteochondral allografts (OCA). Recent biochemical analysis has shown that an acceptable number of viable chondrocytes maybe present at as many of 60 days in MOPS grafts. The prevailing theory is that increased number of viable cell available in donor grafts should increase the rate of incorporation at the host site and potential increase in functional impact. The goal of our study was to assess short term functional outcome measures following treatment of symptomatic chondral lesions treated with MOPS.
Methods
A retrospective review of 53 patients with symptomatic knee chondral lesions treated with MOPS were evaluated retrospectively for safety and improvement in functional outcomes. Patient demographic information was collected and assessed against the following benchmarks: Short Form-12 (SF-12), Subjective International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm Knee Scoring System, Visual Anologue Scale (VAS) Pain Severity scores, and Pain Frequency scores.
Results
Fifty-three patients were evaluated pre-operatively and post-operatively at 3 months, 12 months, and 24 months. Lysholm, IKDC, SF-12, and KOOS: Pain, Symptoms, ADLs Sports, QOL, VAS and Pain frequency scores improved at each follow up compared to pre-operative baseline (POB). These trends were maintained at most recent follow up (average 24.5 months) with significant increases compared to pre-operative baseline (POB) of IKDC scores (48.77?24.05 versus 31.05?15.0, p < .001), Lysholm scores (61.34?26.0 versus 40.42?18.8, p < .001), and KOOS scores: Pain (66.03?26.4 versus 51.71?24.1, p<0.003), Symptom (66.96?23.3 versus 48.71?19.7, p < .001), ADL (70.38?28.1 versus 56.85?22.4, p=0.002), Sports (39.77?30.5 versus 19.67?19.9, p < .001), QOL (42.46?31.1 versus 17.88?15.7, p < .001), and PSF-12 scores (36.69?11.19 versus 30.79?6.43, p < .001). At most recent follow up VAS and pain frequency ratings had improved by 4.3 and 2.1 (p < .001), respectively.
Conclusion
Our clinical results demonstrate significant increases in functional scores at the time of latest follow up compared to POB when MOPS was used to treat symptomatic articular cartilage lesions. This short-term follow-up data in this patient population indicates that patients who received the MOPS OCA can expect to gradually improve over a time period of 12 months with maintenance at 24 months as evidenced by multiple modalities of functional scoring. Future Long term studies and randomized controlled trials is needed to validate the efficacy and superiority of MOPS compared to the standard of care.