RESUMO
PURPOSE: The purpose of the present review is to systematically review the available literature for failure rates and complications of cartilage restoration of bipolar chondral defects in the patellofemoral (PF) joint to assess the ability to treat these lesions without arthroplasty. METHODS: PubMed and MEDLINE databases were queried between 2000 to 2020 using the keywords "osteochondral" and "knee" and "microfracture," "autologous chondrocyte implantation (ACI)," or "transplantation." Patient selection included patients with bipolar chondral lesions of the patellofemoral joint that were treated with cartilage restoration procedures. Treatment of PF joints were reviewed for surgical indications/technique, rates of failure, defect characteristics, and time to failure. For the purposes of this study, failure was defined by each individual author on their respective studies. RESULTS: After screening 1,295 articles, there were 8 publications analyzed quantitatively and 10 articles analyzed both quantitatively and qualitatively. A total of 249 knees involved bipolar lesions of the patellofemoral joint. The weighted average age was 36.5 ± 10.4 years, and weighted average follow-up was 89.0 ± 31.7 months. There were failures in 0% to 50% of cases, revision procedures in 0% to 10% of cases, conversion to arthroplasty in in 0% to 50% of cases, and unsatisfactory outcome without revision in 0% to 8.3% of cases. The range in average failure rate was 0% to 50.0% (I2 = 68.0%), whereas the range in average time to failure was 2.9 to 6.8 years (I2 = 79.0%). CONCLUSION: From the available data, established cartilage restoration procedures may provide favorable patient-reported function, avoidance of secondary surgery, and joint preservation in at least 80% of patients at short- to mid-term follow-up. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.
RESUMO
PURPOSE: The purpose of the present study is to systematically review the available literature for management of bipolar lesions within the tibiofemoral joint and determine whether tibiofemoral cartilage restoration is an effective treatment modality. METHODS: PubMed and MEDLINE databases were queried between 2000 and 2020 using the following keywords: "osteochondral" and "knee" and "microfracture," "autologous chondrocyte implantation (ACI)," or "transplantation." Articles were reviewed for the presence of a bipolar or "kissing" tibiofemoral lesion and reported lesion size, concomitant procedures, failure rates, and time to failure. RESULTS: After screening 1,295 articles, there were 4 articles available for analysis and a total of 152 knees involving the management of bipolar tibiofemoral lesions. Age ranged from 14 to 60 years, and mean follow-up was between 12 and 240 months. There was 1 retrospective cohort study (36 knees) and 3 case series (mean, 38.7 ± 17.5 knees). There were 58 knees treated with bipolar osteochondral allograft (OCA) transplantation, 58 knees treated with bipolar ACI, 20 knees treated with femoral OCA and tibial debridement, and 16 knees treated with femoral OCA and tibial microfracture. There were 37 failures (24.3%): 16 patients (10.5%) were converted to unicompartmental or total knee arthroplasty, 4 restorative procedures (2.6%) were revised, and 8 patients (1.6%) had unsatisfactory outcomes only. The remaining 15 failures (9.9%) had an unspecified combination of objective failure. The mean rate of failure ranged between 0% and 44.1% (I 2 = 83.2%). The mean time to failure ranged between 2.7 and 4.1 years (I 2 = 79.1%). CONCLUSIONS: Cartilage restoration, through both ACI and OCA, had failure rates between 0% and 44% in patients with bipolar lesions of the tibiofemoral compartment. Although a higher level of evidence is required to prove efficacy, the current study demonstrates midterm survivorship rates between 55% and 100%, which may delay the need for secondary arthroplasty. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.
