Extended Abstract (for invited Faculty only) Cartilage /Cell Transplantation

2.0.2 - Restore Joints - A Complex Task?

Presentation Topic
Cartilage /Cell Transplantation
Date
12.04.2022
Lecture Time
13:30 - 13:45
Room
Potsdam 1
Session Type
Plenary Session
Speaker
  • T. Minas (West Palm Beach, US)
Authors
  • T. Minas (West Palm Beach, US)

Abstract

Introduction

The success of cartilage repair techniques in the knee joint is multifaceted. A fundamental element to successful clinical outcomes is addressing the causation of the articular cartilage breakdown. Abnormal anatomy and altered biomechanical loading are common factors causing or contributing to cartilage loss in the knee. Such co-pathologies or “background factors” include tibiofemoral malalignment or meniscal deficiency, which exposes a joint compartment to excessive overloading. Altered patellofemoral alignment and kinematics are additional pathological features attributed to cartilage loss. When all causative factors are addressed, even the most advanced cases are amenable to biological repair with good to excellent clinical outcomes.

Content

The success of cartilage repair techniques in the knee joint is multifaceted. A fundamental element to successful clinical outcomes is addressing the causation of the articular cartilage breakdown. Abnormal anatomy and altered biomechanical loading are common factors causing or contributing to cartilage loss in the knee. Such co-pathologies or “background factors” include tibiofemoral malalignment or meniscal deficiency, which exposes a joint compartment to excessive overloading. Altered patellofemoral alignment and kinematics are additional pathological features attributed to cartilage loss. When all causative factors are addressed, even the most advanced cases are amenable to biological repair with good to excellent clinical outcomes.

For example, bipolar or “kissing” lesions in the patellofemoral compartment, a notoriously difficult problem for orthopedic surgeons, can be successfully treated with autologous chondrocyte implantation (ACI) and a concomitant osteotomy, when warranted. A case series of 58 patients (60 knees) who underwent ACI for repair of bipolar patellofemoral lesions demonstrated significant improvement in pain and function, with good survival rates at 5 and 10 years postoperatively (83% and 79%, respectively). Of this cohort, 42 (72%) patients had a corrective osteotomy for either patellofemoral lateral maltracking, patellar instability, or tibiofemoral malalignment. The best survivorship rates were observed among the patients who underwent ACI with a concurrent tibial tubercle osteotomy (TTO). Additional unpublished subcohort analysis demonstrated a 10-year survival rate of 91% when a TTO was performed at the time of ACI using a type I/III bilayer collagen membrane.

Likewise, we showed that ACI for the treatment of symptomatic bipolar cartilage lesions in the tibiofemoral compartments provides successful clinical outcomes in patients at mid- to long-term follow-up. Predisposing risk factors were addressed through concurrent osteotomies in 44 (76%) of the 58 knees. In this series, the survival rate was 80% at 5 years and 76% at 10 years, with significantly higher survival rates in the cohort of patients treated with collagen membrane versus periosteum (97% vs 61% at 5 years, respectively; p = .0014). The patient satisfaction was also high. Of the 46 knees with retained grafts, 91% were satisfied with their outcome, 85% rated their knee as better with the surgery, and 83% rated their outcome as good or excellent at a mean 8.3 years follow-up. At the final follow-up, 24 of the 46 successful knees were radiographically assessed and showed no significant osteoarthritis progression in K-L grading.

Another challenging problem for orthopedic surgeons that can be managed with consideration of the predisposing factors are cartilage lesions in the presence of meniscal deficiency. Our study evaluating 17 symptomatic patients (18 knees) with concomitant cartilage lesions and meniscal deficiency demonstrated 5- and 10-year survival rates of 75% with patient-reported functional improvements at a mean 7.9 years postoperative when meniscal allograft transplantation (MAT) was performed at the time of ACI. Of the cohort, there was no significant osteoarthritic progression using K-L grading from preoperative to mean 5.9 years postoperative. Thirteen patients (76%) maintained their native knee at the final follow-up.

All in all, challenging cases, ranging from bipolar cartilage lesions of the patellofemoral and tibiofemoral joints to cartilage lesions with concurrent meniscal deficiency, can be successfully treated through a means of joint preservation. Careful consideration and management of the causative factors, however, is imperative for good clinical outcomes.

References

Ogura T, Bryant T, Minas T. Biological Knee Reconstruction With Concomitant Autologous Chondrocyte Implantation and Meniscal Allograft Transplantation: Mid- to Long-term Outcomes. Orthop J Sports Med. 2016;4(10):2325967116668490. Published 2016 Oct 19. doi:10.1177/2325967116668490.

Ogura T, Bryant T, Merkely G, Minas T. Autologous Chondrocyte Implantation for Bipolar Chondral Lesions in the Patellofemoral Compartment: Clinical Outcomes at a Mean 9 Years' Follow-up. Am J Sports Med. 2019;47(4):837-846. doi:10.1177/0363546518824600.

Ogura T, Bryant T, Mosier BA, Minas T. Autologous Chondrocyte Implantation for Bipolar Chondral Lesions in the Tibiofemoral Compartment. Am J Sports Med. 2018;46(6):1371-1381. doi:10.1177/0363546518756977.

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