Patient-specific metal implants for focal chondral and osteochondral lesions in the knee; excellent clinical results at 2 years

Johannes Holz*, Tim Spalding, Tarek Boutefnouchet, Pieter Emans, Karl Eriksson, Mats Brittberg, Lars Konradsen, Clemens Koesters, Peter Verdonk, Magnus Hogstrom, Martin Lind

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Purpose Surgical treatment options for the management of focal chondral and osteochondral lesions in the knee include biological solutions and focal metal implants. A treatment gap exists for patients with lesions not suitable for arthroplasty or biologic repair or who have failed prior cartilage repair surgery. This study reports on the early clinical and functional outcomes in patients undergoing treatment with an individualised mini-metal implant for an isolated focal chondral defect in the knee. Methods Open-label, multicentre, non-randomised, non-comparative retrospective observational analysis of prospectively collected clinical data in a consecutive series of 80 patients undergoing knee reconstruction with the Episealer (R) implant. Knee injury and Osteoarthritis Outcome Score (KOOS) and VAS scores, were recorded preoperatively and at 3 months, 1 year, and 2 years postoperatively. Results Seventy-five patients were evaluated at a minimum 24 months following implantation. Two patients had undergone revision (2.5%), 1 declined participation, and 2 had not completed the full data requirements, leaving 75 of the 80 with complete data for analysis. All 5 KOOS domain mean scores were significantly improved at 1 and 2 years (p <0.001-0.002). Mean preoperative aggregated KOOS4 of 35 (95% CI 33.5-37.5) improved to 57 (95% CI 54.5-60.2) and 59 (95% CI 55.7-61.6) at 12 and 24 months respectively (p <0.05). Mean VAS score improved from 63 (95% CI 56.0-68.1) preoperatively to 32 (95% CI 24.4-38.3) at 24 months. The improvement exceeded the minimal clinically important difference (MCID) and this improvement was maintained over time. Location of defect and history of previous cartilage repair did not significantly affect the outcome (p > 0.05). Conclusion The study suggests that at 2 years, Episealer (R) implants are safe with a low failure rate of 2.5% and result in clinically significant improvement. Individualised mini-metal implants with appropriate accurate guides for implantation appear to have a place in the management of focal femoral chondral and osteochondral defects in the knee.

Original languageEnglish
Pages (from-to)2899-2910
Number of pages12
JournalKnee Surgery Sports Traumatology Arthroscopy
Issue number9
Early online date6 Oct 2020
Publication statusPublished - Sept 2021


  • Focal cartilage lesion
  • Focal knee resurfacing
  • Metal implants
  • Clinical outcomes
  • Customised
  • Personalized

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