Low postoperative complication rate with high survival rate and good clinical outcome 9 years after autologous chondrocyte transplantation of the knee joint

Abstract

Purpose To investigate postoperative complications and associated risk factors for failure following autologous chondrocyte transplantation (“ACT”) as well as its long-term survival and clinical function. It was hypothesized that ACT is a safe technique for cartilage repair with a low incidence of postoperative complications and rare rates of revision surgery combined with a high long-term survival and good to excellent clinical outcome in long-term-follow-up. Methods All patients undergoing ACT-Cs of the knee joint between 2006 and 2012 at the author’s institution were included in this retrospective study. Concomitant procedures had been performed if necessary. Early postoperative complications, revision surgeries, failure and risk factors for those events were evaluated 6 months after the surgery. Long-term clinical outcome was assessed using the Lysholm Score, the Tegner Score, a 10-grade scale for satisfaction and the Visual Analogue Scale (VAS) at a minimum follow-up of 9 years postoperatively. Long-term survival was calculated using revision surgeries, clinical failures and conversion procedures to create a Kaplan–Meier analysis. A subgroup analysis for different defect locations was performed. 139 patients were included in this study (27% female/ 73%male; age 26.7 [21.7; 35.2] years). The median defect size was 4.0 [3.0; 6.0] cm2 (40% medial femoral condyle (MFC), 17% lateral femoral condyle (LFC), 36% patella, 19% trochlea). 97 (70%) of the patients had undergone previous surgery and 84 (60%) underwent concomitant procedures. Results Postoperatively, 8% of patients had complications (4% bleeding, 2% arthrofibrosis, 2% infection), 7% of patients needed revision surgery. 12% of patients had a prolonged deficit in ROM, that did not require revision surgery. No significant difference in terms of complications was found between the patellofemoral and femorotibial group. Patients demonstrated good patient reported long-term outcomes 9–15 years after the index surgery (Tegner: 4.7 ± 1.8; VAS: 2.4 ± 2.1; Lysholm: 80 ± 14; satisfaction with operation: 7.3 ± 1.9). Survival rates were 88% at 9 years, 85% at 11 years, and 85% at 13 years after the index procedure. Reasons for failure included debridement of ACT (n = 4; 5%), revision ACT (n = 3, 3%), conversion to total knee arthroplasty (n = 3, 3%) and conversion to High tibial osteotomy (HTO) (n = 1; 1%)). Conclusion The present study indicates ACT as an effective treatment option for femorotibial- as well as patellofemoral cartilage defects with a high long-term survival and low conversion rate as well as good long-term results regarding knee function and satisfaction. Postoperative complications needing revision surgery are rare. Prolongated deficits of range of motion appear frequently up to six months especially in patellofemoral defects, but can often be successfully addressed by intensified physiotherapy without requiring an arthrolysis. Level of evidence Level III.

Increased risk of reoperation and failure to attain clinically relevant improvement following autologous chondrocyte implantation of the knee in female patients and individuals with previous surgeries: a time‐to‐event analysis based on the German cartilage registry (KnorpelRegister DGOU)

“…This variability in reoperation rates underscores the need for further investigation. While we acknowledge the potential for an attrition bias due to a higher loss to follow-up in patients undergoing reoperations, our findings are consistent with previous studies [ 6 , 11 , 16 , 20 , 26 ].…”

“…Conversely, a systematic review from 2016 reported lower reoperation rates compared to our findings, with a pooled rate of 5% for patients undergoing reoperation at 2–5 years follow-up [ 26 ]. Furthermore, a recently published 9-year follow-up study of patients undergoing ACI reported a very low revision surgery rate of 7% [ 6 ]. This variability in reoperation rates underscores the need for further investigation.…”

“…Fig 6. Average group-level Knee Injury and Osteoarthritis Outcome Score (KOOS) subscores of patients with and without reoperation following autologous chondrocyte implantation (ACI).…”

Autologous minced cartilage repair for chondral and osteochondral lesions of the knee joint demonstrates good postoperative outcomes and low reoperation rates at minimum five‐year follow‐up

“…Overall surgery-related complications and revision surgery are relatively low and comparable between different chondral regenerative techniques [ 18 , 28 , 44 , 46 ]. Graft hypertrophy after MACI was reported in 12% of the patients after five years with a need for revision surgery in 8% [ 16 ].…”

“…Osteochondral autograft transfer system (OATS), autologous chondrocyte implantation (ACI), matrix-assisted chondrocyte implantation (MACI) or several cartilage repair techniques using scafolds (natural or synthetic) are contemporarily the most commonly therapies for medium to large defects [7,22]. ACI and MACI are purported to generate hyaline or hyaline-like cartilage, with low associated reoperation rates and favourable clinical outcomes even in complex cases [5,7,18,29,49]. However, the two-step approach of ACI and MACI, which requires laboratory cell cultivation, results in a high inancial and clinical burden.…”