Deciding How Best to Treat Cartilage Defects

Outcomes of Arthroscopic Joint Preservation Techniques for Chondral Lesions in the Hip: An Updated Systematic Review

PURPOSE

To systematically review outcomes of joint preservation procedures for chondral lesions of the hip through analysis of survival rates and patient-reported outcomes (PROs).

METHODS

A literature search from 2018 to May 2023 was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in 3 databases: PubMed, Embase, and Google Scholar. Studies were included if they reported on outcomes of patients undergoing hip arthroscopy for the treatment of chondral lesions of the hip joint and if there were quantifiable postoperative outcome measures. Quality assessment was completed using the Methodological Index for Non-Randomized Studies criteria.

RESULTS

Twenty-seven studies were included, with 20 noncomparative and 7 comparative studies. Microfracture (MFx) was the most common procedure, reported in 17 studies. Other procedures include autologous chondrocyte transplantation (ACT) (5 studies), autologous matrix-induced chondrogenesis (AMIC) (3 studies), and MFx in conjunction with CarGel (3 studies). Seven other novel procedures were reported in individual separate studies. Survival rates, defined by no revision surgery or conversion to total hip arthroscopy (THA) at latest follow-up, for MFx (14 studies), AMIC (3 studies), and MFx in conjunction with CarGel (3 studies) ranged from 59.1% to 100%, 92.9% to 100%, and 94.4% to 95.7%, respectively. Survival rates of ACT, biological reconstruction, debridement and abrasion, microfragmented autologous adipose tissue transplantation, and ChondroFiller gel were all reported once in separate studies with rates of 100%, 100%, 85.4%, 100%, and 92.3%, respectively. All studies included PROs, most reporting statistically significant improvements (P < .05) at the latest follow-up.

CONCLUSIONS

Isolated MFx remained the most commonly performed technique, but with lower survival and higher conversion to THA rates than in studies before 2018. Novel techniques that were performed in conjunction with MFx or that avoided MFx altogether had higher overall survival rates despite being minimally performed. Most patients across all techniques demonstrated significant improvements in PROs.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III and IV studies.

Mosaicplasty of the Femoral Head: A Systematic Review and Meta-Analysis of the Current Literature

Osteochondral lesions of the femoral head are rare. For the treatment of these lesions, various joint-preserving procedures, particularly in young, active patients, have been developed. Mosaicplasty is a well-established surgical procedure for the knee. However, there is little evidence that this method can also be used to treat osteochondral lesions in the hip. The indication for cartilage procedures continues to evolve for the knee, and a similar strategy may be adopted for the hip joint. Due to limited evidence and a lack of experience, mosaicplasty treatment of these lesions remains challenging, especially in young patients. This study shows that open and arthroscopic management using the knee and femoral head as donor sites yielded good to excellent short- to mid-term outcomes. For osteochondral lesions of the femoral head, mosaicplasty may be a new alternative treatment option, although this needs to be proven with longer follow-ups and in a larger sample of patients.

Arthroscopic debridement for focal articular cartilage lesions of the knee: A systematic review

BACKGROUND AND PURPOSE OF THE STUDY

Arthroscopic debridement, the most commonly applied surgical technique for focal cartilage lesions in the knee, is not included in most treatment algorithms because of discouraging results in the management of osteoarthritis of the knee. The present systematic review evaluates the outcome of arthroscopic cartilage debridement as the primary treatment of focal knee chondral lesions in adults, and defines its indications and role as the primary treatment of focal knee chondral lesions.

METHODS

Two independent investigators searched PubMed, Cochrane CENTRAL, and Virtual Health Library databases using the terms "knee", "cartilage", "chondral", "lesions", "injury", "damage", "debridement", "chondroplasty", "chondrectomy", alone and in combination. Clinical studies evaluating the effect of mechanical cartilage debridement in adults with symptomatic focal cartilage lesions in the knee joint regardless of the defect size and depth were included. We excluded studies if patients had a concomitant ligament or meniscus injury, and/or had additional debridement with monopolar radiofrequency energy.

MAIN FINDINGS

Available studies suggest good to excellent short and medium-term functional outcomes (KOOS, LKSS, Tegner scale) for focal cartilage lesions treated with debridement regardless of the defect size and depth. Data are lacking comparing cartilage debridement versus other cartilage repair techniques.

CONCLUSIONS

Arthroscopic debridement of focal articular cartilage lesions of the knee is associated with good to excellent short and medium-term postoperative outcomes, especially in terms of functional improvement. Arthroscopic debridement may be considered in the primary treatment of focal cartilage injuries regardless of the defect size and depth. However, available studies are limited and the level of evidence is low.

Nonsurgical Management of Cartilage Defects of the Knee: Who, When, Why, and How?

The nonoperative practitioner managing individuals with cartilage defects should use a patient-centered, multifaceted approach that aims to individualize treatment to provide optimal benefit. These include addressing modifiable risk factors for disease progression and instituting interventions such as weight loss, nutrition, physical activity, and potentially regenerative medicine strategies. This review will focus on these nonoperative treatment strategies with a focus on when treatments are necessary, who will benefit from these approaches, why they are specifically appropriate, and, finally, how these treatments directly modify the structure of a patient's cartilage and resulting symptoms.

The Use of Particulated Juvenile Allograft Cartilage for the Repair of Porcine Articular Cartilage Defects

BACKGROUND

The repair of porcine articular cartilage defects by using particulated juvenile allograft cartilage (PJAC) has demonstrated good short-term clinical efficacy, but the repair process and mechanism have not been fully elucidated.

PURPOSE

To study the efficacy of PJAC in repairing full-thickness cartilage defects and to provide an experimental basis for its clinical application.

STUDY DESIGN

Controlled laboratory study.

METHODS

Thirty Guizhou minipigs were randomly divided into an experimental group and control group. An 8-mm cylindrical full-thickness cartilage defect was created in the femoral trochlea of either knee in all minipigs. The experimental group received the PJAC transplantation (PJAC group; n = 15) and the control group received autologous cartilage chips (ACC group; n = 15). Five minipigs were euthanized at 1, 3, and 6 months in each group to obtain samples, which were evaluated by general view of the knee joint and histomorphometry of the chondral defect area (hematoxylin and eosin, safranin O). International Cartilage Repair Society (ICRS) II semiquantitative evaluation and collagen type II staining immunohistochemistry were also performed.

RESULTS

All 30 Guizhou minipigs were followed; there was no infection or incision healing disorder after the operation. At 1 month postoperatively, more hyaline cartilage was found in the ACC group (29.4%) compared with the PJAC group (20.1%) (P < .05); there was no statistical difference between the 2 groups at 3 and 6 months after operation. The fibrocartilage content in the ACC group was significantly more than that in the PJAC group at 1 and 3 months postoperatively (27.4% vs 18.2% and 49.9% vs 41.1%, respectively; P < .05); significant differences disappeared at 6 months postoperatively. The PJAC group produced more fibrous tissue than the ACC group at 1 and 3 months postoperatively (60.1% vs 40.6% and 38.8% vs 24.4%, respectively; P < .05) but showed no statistical difference at 6 months postoperatively. Regarding the ICRS II scores, those of the ACC group were significantly better than the scores of the PJAC group in some subclasses at 3 and 6 months postoperatively. The positive rates of immunohistochemical staining in the ACC group were higher at 1 and 3 months postoperatively than those in the PJAC group (54.2% vs 37.8% and 46.4% vs 34.4%, respectively; P < .05). The difference was not statistically significant between the 2 groups at 6 months postoperatively.

CONCLUSION

Both PJAC and ACC can produce a good repair effect on cartilage defects. At 1 and 3 months postoperatively, ACC resulted in better outcomes than PJAC, but there was no statistical difference in the repair effect between the 2 techniques at 6 months postoperatively.

CLINICAL RELEVANCE

Based on this animal experiment, further clinical studies are needed to investigate PJAC as a possible alternative first-line treatment for cartilage defects.

Chondral lesions in the hip: a review of relevant anatomy, imaging and treatment modalities

The diagnosis and treatment of chondral lesions in the hip is an ongoing challenge in orthopedics. Chondral lesions are common and several classification systems exist to classify them based on severity, location, radiographic parameters, and potential treatment options. When working up a patient with a potential hip chondral lesion, a complete history, thorough physical exam, and ancillary imaging are necessary. The physical exam is performed with the patient in standing, supine, prone, and lateral positions. Plain film radiographs are indicated as the first line of imaging; however, magnetic resonance arthrogram is currently the gold standard modality for the diagnosis of chondral lesions outside of diagnostic arthroscopy. Multiple treatment modalities to address chondral lesions in the hip exist and new treatment modalities continue to be developed. Currently, chondroplasty, microfracture, cartilage transplants (osteochondral autograft transfer, mosaicplasty, Osteochondral allograft transplantation) and incorporation of orthobiologics (Autologous chondrocyte implantation, Autologous matrix-induced chondrogenesis, Mononuclear concentrate in platelet-rich plasma) are some techniques that have been successfully applied to address chondral pathology in the hip. Further refinement of these modalities and research in novel techniques continues to advance a surgeon’s ability to address chondral lesions in the hip joint.

Nanoparticle Properties for Delivery to Cartilage: The Implications of Disease State, Synovial Fluid, and Off-Target Uptake

A major hurdle limiting the ability to treat and cure osteoarthritis, a common and debilitating disease, is rapid joint clearance and limited cartilage targeting of intra-articular therapies. Nanoscale drug carriers have the potential to improve therapeutic targeting and retention in the joint after direct injection; however, there still lacks a fundamental understanding of how the physicochemical properties of nanoparticles (NPs) influence localization to the degenerating cartilage and how joint conditions such as disease state and synovial fluid impact NP biodistribution. The goal of this study was to assess how physicochemical properties of NPs influence their interactions with joint tissues and, ultimately, cartilage localization. Ex vivo models of joint tissues were used to study how poly(lactide- co-glycolide) (PLGA) and polystyrene (PS) NP size, charge, and surface chemistry influence cartilage retention under normal and disease-mimicking conditions. Of the particles investigated, PLGA NPs surface-modified with a quaternary ammonium cation had the greatest retention within cartilage explants; however, retention was diminished 2- to 2.9-fold in arthritic tissue and in the presence of synovial fluid. Interactions with synovial fluid induced changes to NP surface properties and colloidal stability in vitro. The impact of NP charge on "off-target" synoviocyte uptake was also dependent on synovial fluid interactions. The results suggest that the design of nanocarriers for targeted drug delivery within the joint cannot be based on a single parameter such as zeta potential or size, and that the fate of injected delivery systems will likely be influenced by the disease state of the joint and the presence of synovial fluid.

Outcomes of Osteochondral Allograft Transplantation With and Without Concomitant Meniscus Allograft Transplantation: A Comparative Matched Group Analysis

BACKGROUND

Osteochondral allograft transplantation (OCA) is often performed with concomitant meniscus allograft transplantation (MAT) as a strategy for knee joint preservation, although to date, the effect of concomitant MAT on outcomes and failure rates after OCA has not been assessed.

PURPOSE

To determine clinical outcomes for patients undergoing OCA with MAT as compared with a matched cohort of patients undergoing isolated OCA.

STUDY DESIGN

Control study; Level of evidence, 3.

METHODS

Patients who underwent OCA of the medial or lateral femoral condyle without concomitant MAT by a single surgeon were compared with a matched group of patients who underwent OCA with concomitant MAT (ipsilateral compartment). The patients were matched per age, sex, body mass index, and number of previous ipsilateral knee operations ±1. Patient-reported outcomes, complications, reoperations, and survival rates were compared between groups.

RESULTS

One hundred patients undergoing OCA (50 isolated, 50 with MAT) with a mean ± SD follow-up of 4.9 ± 2.7 years (minimum, 2 years) were included (age, 31.7 ± 9.8 years; 52% male). Significantly more patients underwent OCA to the medial femoral condyle (n = 59) than the lateral femoral condyle (n = 41, P < .0001). Patients underwent 2.7 ± 1.7 operations on the ipsilateral knee before OCA. There were no significant differences between the groups regarding reoperation rate (n = 18 for OCA with MAT, n = 17 for OCA without MAT, P = .834), time to reoperation (2.2 ± 2.4 years for OCA with MAT, 3.4 ± 2.7 years for OCA without MAT, P = .149), or failure rates (n = 7 [14%] for OCA with MAT, n = 7 [14%] for OCA without MAT, P > .999). There were no significant differences in patient-reported clinical outcome scores between the groups at final follow-up. There was no significant difference in failure rates between patients undergoing medial femoral condyle OCA (n = 12, 15.3%) and lateral femoral condyle OCA (n = 5, 12.2%, P = .665).

CONCLUSION

These results imply that with appropriate surgical indications to address meniscus deficiency in patients otherwise indicated for OCA and despite the added surgical time and complexity of concomitant MAT, outcomes are favorable, with an 86% OCA graft survivorship at 5 years. This information can be used to counsel patients undergoing OCA with concomitant MAT as part of a knee joint preservation strategy.

The Utility of Biologics, Osteotomy, and Cartilage Restoration in the Knee

The management of complex cartilage and meniscal pathology in young, athletic patients is extremely challenging. Joint preservation surgery is most difficult in patients with concomitant knee pathologies, including cartilage defects, meniscal deficiency, malalignment, and/or ligamentous insufficiency. Clinical decision making for these patients is further complicated by articular cartilage lesions, which often are incidental findings; therefore, treatment decisions must be based on the confirmed contribution of articular cartilage lesions to symptomatology. Surgical management of any of the aforementioned knee pathologies that is performed in isolation typically results in acceptable patient outcomes; however, concomitant procedures for the management of concomitant knee pathologies often are essential to the success of any single procedure. The use of biologic therapy as an alternative to or to augment more conventional surgical management has increased in popularity in the past decade, and indications for biologic therapy continue to evolve. Orthopaedic surgeons should understand knee joint preservation techniques, including biologic and reconstructive approaches in young, high-demand patients.