During medical record review, diagnosis, history of procedures prior to ACI, lesion location, lesion size, age at implantation, concomitant procedure performed during ACI, ACI procedure details, postoperative complications, and contralateral knee surgeries were extracted and documented to confirm JOCD history and status following ACI.
Baseline characteristics of patients including current age, height, weight, and body mass index (BMI) along with history of JOCD and detailed information of orthopedic procedures prior to ACI were examined.
Baseline information of physical characteristic, JOCD history, and orthopedic procedures for JOCD prior to ACI were determined for the ten patients enrolled in this study (Table 1).
To our knowledge, this is the first long-term study of ACI treatment of knee JOCD patients using patients' reported outcome measures: KOOS, IKDC, Modified Cincinnati Knee Rating scores, and treatment history survey.
These outcomes are considered to defer from ACI outcomes in JOCD due to the lack of underlying bone pathology and involvement.
Compared to the results of this study, a shorter follow-up study employed a similar cohort of JOCD patients with several years of follow-up duration (minimum of two years and mean follow-up time of four years) .
JOCD of the knee occurs most frequently in the classic location of the posterolateral aspect of the medial femoral condyle, as it is reported in more than 70% of cases.
There have been numerous theories proposed to explain the cause of JOCD of the knee.
(4,5,7) Other studies have suggested that a genetic component to this pathology is likely due to bilateral presentation in up to 30% of cases along with the fact that many individuals experiencing JOCD may have osteochondral defects in multiple joints.
In 1933, Fairbanks (15) proposed a traumatic mechanism where impaction of the tibial spine on the lateral aspect of the medial femoral condyle leads to the common presentation of JOCD. However, this mechanism can only explain the development of lesions in the classic site of the medial femoral condyle, and does not support those occurring in other areas, such as the lateral femoral condyle and patella.
They found that approximately 55% of the young patients with confirmed JOCD were regularly active in sports and performed strenuous athletic activity.
Theories such as aberrant joint loading and issues with epiphyseal endochondral ossification have also been suggested to contribute to the proposed multifaceted etiology of JOCD of the knee.