Arthroscopic Cartilage Lesion Preparation in the Human Cadaveric Knee Using a Curette Technique Demonstrates Clinically Relevant Histologic Variation

Surgeon Ability to Appropriately Address the Calcified Cartilage Layer: An In Vitro Study of Arthroscopic and Open Techniques

BACKGROUND

Microfracture is a commonly utilized cartilage restoration technique for articular cartilage defects. While the removal of the calcified cartilage layer (CCL) has been shown to be critical with in vivo models, little is known with regard to surgeon reliability to adequately perform the technique.

PURPOSE

To evaluate surgeon reliability in removing the CCL utilizing open and arthroscopic techniques.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eleven cadaveric knees were utilized to create four 12-mm diameter defects in the anterior and posterior medial femoral condyles. Eleven fellowship-trained surgeons were asked to perform the following procedures: remove the CCL open, retain the CCL open, remove the CCL arthroscopically, and retain the CCL arthroscopically. Samples underwent histologic staining and analysis with 3-dimensional micro-computed tomography. The latter was used to calculate the percentage of the CCL that was removed or retained across the entire defect.

RESULTS

When surgeons were asked to retain the CCL arthroscopically, 48% ± 41% (mean ± SD) remained. When surgeons were asked to remove the CCL arthroscopically, 24% ± 35% remained. There was no statistical difference between these groups (P > .05). When the CCL was retained during open preparation, 60% ± 39% remained. During attempts to remove the CCL in an open manner, 19% ± 28% remained. There was a significant difference in the amount of CCL remaining between the open removal and open retaining groups (P = .03). There were no significant differences in the percentage of CCL remaining between the open and arthroscopic preservation groups and between the open and arthroscopic removal groups.

CONCLUSION/CLINICAL RELEVANCE

This study highlights the significant variability in surgeon ability to reliably retain or remove the CCL. However, there appears to be improved ability of surgeons to more reliably remove or retain the CCL in an open fashion as compared with the arthroscopic approach.

Long-term Clinical Outcomes of One-Stage Cartilage Repair in the Knee With Hyaluronic Acid-Based Scaffold Embedded With Mesenchymal Stem Cells Sourced From Bone Marrow Aspirate Concentrate

BACKGROUND

Cell-based cartilage repair performed as a single-stage procedure is an important advancement in the treatment of full-thickness cartilage injury and has potential for widespread clinical use.

PURPOSE

To investigate the long-term clinical outcomes of cartilage repair in the knee with a hyaluronic acid-based scaffold embedded with bone marrow aspirate concentrate (HA-BMAC) for the treatment of full-thickness cartilage injury.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients underwent treatment of full-thickness chondral injury in the knee with HA-BMAC and were followed prospectively for a minimum of 6 years. Clinical outcomes were examined with patient-reported scoring instruments that consisted of the Tegner Activity Scale, International Knee Documentation Committee (IKDC) subjective score, visual analog scale, and Knee injury and Osteoarthritis Outcome Score (KOOS). Comparative analysis of pre- and postoperative scores was performed, and the effects of patient age, body mass index, lesion size, number of treated lesions, and concurrent treatment with associated procedures were examined.

RESULTS

Twenty-three patients (mean age, 48.5 years) were followed prospectively for a mean 8 years (range, 6-10 years). Median cartilage lesion size was 6.5 cm² (range, 2-27 cm²). At final follow-up, median Tegner, visual analog scale, and IKDC subjective scores were 4, 0.3, and 85, respectively. Final median KOOS subset scores were as follows: Pain, 94; Symptoms, 89; Activities of Daily Living, 99; Sports/Recreation, 85; and Quality of Life, 85. All scores were significantly increased at final follow-up ( P < .001). Comparable median outcome scores were demonstrated after categorization of patients by age, lesion size, treatment of multiple lesions, treatment of multiple knee compartments, and treatment by associated procedures. Rank correlation analysis demonstrated a negative correlation between patient age and final outcome scores of the IKDC, Tegner, and KOOS subsets of Pain, Activities of Daily Living, and Sports/Recreation. No associations were identified between body mass index or lesion size and outcome scores.

CONCLUSION

Repair of full-thickness cartilage injury in the knee with a HA-BMAC provides good to excellent clinical outcomes at long-term follow-up in the treatment of small to large lesions. Cartilage repair with HA-BMAC leads to comparatively successful long-term outcomes in the treatment of small or large lesions, single or multiple lesions, and lesions in 1 or 2 compartments, as well as in cases of associated lesion treatment. While good outcomes can be expected among treated patients >45 years of age, outcomes may be comparatively more successful in younger patients.

Editorial Commentary: Acetabular Cartilage Repair: A Critically Important Frontier in Hip Preservation

Articular cartilage damage to the acetabulum is frequently associated with femoroacetabular impingement, and there are considerable long-term implications for such injury with regard to maintenance of a healthy hip joint and quality of life. Developing treatments capable of restoring articular cartilage to acetabular cartilage defects is of great importance if hip preservation treatments are to be successful. Ideally, such methods should be performed in a minimally invasive manner and be capable of restoring durable repair tissue that reconstitutes a healthy osteochondral unit and that continues to function effectively over the long term.

Editorial Commentary: Can We Really See the Calcified Cartilage Layer When Debriding Focal Cartilage Defects?

Cell-based cartilage restoration techniques have made huge leaps in recent years; however, many hurdles still lay ahead, one of which is the fundamental task of preparing the cartilage lesion site. Although it is one of the first skills an arthroscopist learns during training, it seems that current techniques and instrumentation still yield inconsistent results, which can hinder patient outcomes.