Autologous Costal Chondral/Osteochondral Transplantation and Costa‐Derived Chondrocyte Implantation for Articular Cartilage Repair: Basic Science and Clinical Applications

Abstract

There has been increasing application of autologous costal chondral/osteochondral transplantation (ACCT/ACOT) and costa‐derived chondrocyte implantation (ACCI) for articular cartilage repair over the past three decades. This review presents the major evidence on the properties of costal cartilage and bone and their qualifications as grafts for articular cartilage repair, the major clinical applications, and the risks and strategies for costal chondral/osteochondral graft(s) harvest. First, costal cartilage has many specific properties that help restore the articular surface. Costa, which can provide abundant cartilage and cylindrical corticocancellous bone, preserves permanent chondrocyte and is the largest source of hyaline cartilage. Second, in the past three decades, autologous costal cartilage‐derived grafts, including cartilage, osteochondral graft(s), and chondrocyte, have expanded their indications in trauma and orthopaedic therapy from small to large joints, from the upper to lower limbs, and from non‐weight‐bearing to weight‐bearing joints. Third, the rate of donor‐site complications of ACCT or ACOT is low, acceptable, and controllable, and some skills and accumulated experience can help reduce the risks of ACCT and ACOT. Costal cartilage‐derived autografting is a promising technique and could be an ideal option for articular chondral lesions with or without subchondral cysts. More high‐quality clinical studies are urgently needed to help us further understand the clinical value of such technologies.

Autologous costa‐derived chondrocyte implantation and autologous costal chondral/osteochondral transplantation for articular cartilage repair and its timeline of clinical application.

Introduction

Osteochondral lesions are a common and difficult injury for diarthrosis, ¹ , ² and symptomatic osteochondral lesions are challenging clinically due to the limited capacity for intrinsic healing and repair of articular cartilage. ³ Following the failure of conservative treatments, many patients seek surgical treatment, with the major aim to restore the articular surface using a graft similar to the native cartilage of the host site and to achieve a long‐term effect. ² , ⁴ Over the past few decades, various techniques and biomaterials have emerged for chondral and osteochondral lesions repair, including injection of biological products, ⁵ , ⁶ microfracture, ⁷ autologous osteoperiosteal transplantation, ⁸ , ⁹ and allografting and autografting osteochondral transplantation. ⁸ , ¹⁰ Most surgical techniques has relatively limited indications, and the optimal management of osteochondral lesions remains controversial. ¹¹

Allograft and autograft consisting of almost the same chondral/osteochondral structure and properties might be the best match for articular cartilage repair. However, due to the imbalance between the increasing clinical demand and limited resources, these techniques are restricted and cannot be expanded to treat more patients. ¹² Autologous costal chondral/osteochondral transplantation could be an ideal treatment for articular chondral lesions with or without subchondral cysts. Since autologous costal chondral transplantation has been used in plastic and cosmetic surgery, there have been increasing practices restoring the articular chondral and osteochondral lesions with costa‐derived graft(s). ¹³ , ¹⁴ , ¹⁵ , ¹⁶ , ¹⁷ , ¹⁸ , ¹⁹

In this review, we discuss the properties of costal cartilage and bone and their qualifications as grafts for articular cartilage repair, the major clinical applications of autologous chondral/osteochondral transplantation and costa‐derived chondrocyte implantation (Figure 1), and the risks and strategies involved in the costal harvest. Through this review, we hope this technique can be better understood.

FIGURE 1.

Schematic of autologous costa‐derived chondrocytes implantation and autologous costal chondral/osteochondral transplantation for articular cartilage repair. Costal (osteo)chondral graft is harvested from the fifth or sixth rib and its amount is determined by the defect of the articular cartilage. Costal‐derived chondrocytes are extracted and expanded in vitro and then are implanted into the cartilage defect. Costal cartilage graft can be shaped and press‐fit into the recipient site of the talus. Osteochondral graft is more suitable for lesions with subchondral cysts. ACCI, autologous costa‐derived chondrocytes implantation; ACCT, autologous costal chondral transplantation; ACOT, autologous costal osteochondral transplantation.

Properties of Costal Cartilage and Bone

Costal cartilage has many specific properties that are helpful for restoring the articular surface. Costa, which can provide abundant cartilage and cylindrical corticocancellous bone, preserves permanent chondrocyte and is the largest source of hyaline cartilage. ¹² , ¹⁶ , ²⁰ , ²¹

Biological Structure and Components of Costal Cartilage

The ribs are generally curved and partially straight in some segments. The size and volume of costal cartilage vary according to the anatomy sites. ²² The average lengths of the sixth, seventh, and eighth costal cartilage of the right side are 98.7, 132.8, and 81.5 mm, respectively. ²² In most segments of costal cartilage, its shape in the cross‐section is oval. The average width of the sixth costal cartilage is above 10 mm and can reach almost 20 mm at its end. ²² The size of costal cartilage is a meaningful and essential value for repairing osteochondral lesions of the talus. Given the larger sizes in some segments and easy shaping, costa can meet many requirements for cartilage volume and shape (Figure 2).

FIGURE 2.

Plasticity of costal cartilage. (A) Costal cartilage segment is cut directly into cube, column, and frustum of a cone. (B) Costal cartilage segment could be trimmed and spliced into different shapes, with smaller or larger grafts.

The chondral extracellular matrix is the residential microenvironment of cells and involves the regulation of chondrocyte phenotype maintenance, proliferation, and chondrogenesis. ¹² Compared with articular cartilage, costal cartilage is also a multilayered structure containing cells arranged in quite similar distributions, and its matrix shows similar characteristics of the composition of hyaline cartilage: plenty of collagen II and glycosaminoglycans (GAGs) and absence of collagen I and SOX‐9. ¹² , ²³ , ²⁴ One evident characteristic of costal cartilage is the presence of surrounding perichondrium. ²³ Importantly, costal cartilage is much more cellular and has a denser chondrocyte population than articular cartilage, and it is an excellent chondrocyte source. ²⁵ Costal cartilage has much faster cell expansion and higher cell yield: 3.0‐fold and 2.6‐fold higher than articular cartilage, respectively. ²¹ More undifferentiated progenitor cells were found at the peripheral surface of costal cartilage. ²¹ This might be due to the costal cartilage taking on more of the development and maintenance of the thoracic contour, requiring more cells and regenerative potential. Some recent studies on co‐culture stem cells and costal chondrocytes also demonstrated the potential of stem cells, co‐culture, and co‐existence for cartilage regeneration and osteochondral defect repair. ²⁶ , ²⁷

Properties of Costal Corticocancellous Bone

Costal bone grafts can be harvested en bloc with reliable composition, annular cortical bone, and inner cancellous bone. ²⁸ The corticocancellous property renders costal bone grafts two unique and inherent advantages. First, the cortical bone provides a structurally sound osteoconductive medium. ²⁹ Possessing a continuous mantle of cortical bone, a full‐thickness rib graft has better axial mechanical strength. ²⁸ Second, the cancellous bone can provide a highly osteoconductive, osteoinductive, and osteogenic substrate. ²⁹ By adding its cartilage, costal osteochondral transplantation can resolve bone and cartilage defects simultaneously.

Requirements of Grafts for Articular Cartilage Repair

The fundamental function of articular cartilage is to help facilitate the transmission of load through its smooth and lubricated interface. ³ Articular cartilage consists of hyaline cartilage and a sparse distribution of chondrocyte, and its thickness is around 2 to 4 mm. ³ Given the abundant amount of water (up to 80% of its wet weight) and ample collagen, of which collagen type II represents 90% to 95%, normal articular cartilage has unique tensile properties and provides great resistance to compressive forces to implement its function. ³ The subchondral bone also provides a great contribution of resistance to compressive force.

Hence, the major requirement of grafts for articular cartilage repair is possessing similar morphology, congruency, hierarchical structure, and biological properties to articular cartilage, especially to the recipient site. Regardless of the choice of repair management, maintaining the congruency of the implanted graft(s) with the native articular surface of the host site is essential. ¹² The best way to repair it is to consider what is missing and what is in the graft(s). Other requirements to consider include the source, availability (ample supply), convenience, operability, and plasticity of the graft(s) and whether there is minimal or no potential donor‐site morbidity. Compared with osteochondral autograft from femoral condyle and osteochondral allograft, autologous costal chondral /osteochondral transplantation has comparable advantages and meets most of the above requirements (Table 1). Costa is an ideal donor for repairing articular cartilage defects. Du et al. (2015) first reported using multiple sliced costal cartilage grafts from a single rib to repair critical osteochondral defects in a rabbit model (5 mm in diameter and 3 mm deep). They performed mosaicplasty and described the host–grafts integration and endochondral ossification after transplantation. ³⁰

TABLE 1.

Comparison of the characteristics of three kinds of grafts for articular cartilage repair, including osteochondral allograft, osteochondral autograft, and costal autograft

	Osteochondral allograft	Osteochondral autograft	Costal autograft
Recipient site	Talar dome	Talar dome	Talar dome
Donor site	Talus	Femoral condyle	Costa
Available supply	Limited, little	Limited, medium	Almost unlimited, ample
Accessibility	Very hard	Convenient	Convenient, easy
Morphology	Almost same	Highly similar	Highly similar after shaping
Congruency	Very high	High	High after shaping
Structure	Same	Highly similar	Highly similar
Plasticity	High	Medium, limited	Very high
Donor‐site morbidity	None	Low to medium, sometimes high	Minimal, low
Immune rejection	Concern	None	None
Cost	High	Low	Low
Clinical outcomes	Effective and acceptable, but high rate of failure and revision	Good, satisfactory	Promising; good in ankle, femoral head, knee, elbow, wrist, and fingers.

Clinical Autologous Costal Chondral/Osteochondral Transplantation and Costa‐Derived Chondrocyte Implantation

Since autologous costal chondral transplantation (ACCT) was first applied in plastic and cosmetic surgery in the 1920s, the indications and number of applications of this technique have increased considerably, and its application has extended to articular cartilage repair. ¹³ , ¹⁶ , ¹⁷ , ³¹ , ³² , ³³ In the past three decades, autologous costal cartilage‐derived grafts, including cartilage, osteochondral graft(s), and chondrocyte, have expanded their indications in trauma and orthopaedic therapy from small to large joints, from the upper to lower limbs, and from non‐weight‐bearing to weight‐bearing joints (Figure 3). ¹⁶ , ¹⁷ , ³¹ , ³² , ³³ , ³⁴ , ³⁵ A summary of clinical studies on autologous costa‐derived grafts transplantation/implantation is provided in Table 2.

FIGURE 3.

Timeline of clinical autologous costal chondral/osteochondral transplantation and costa‐derived chondrocyte implantation. ACOT, autologous costal osteochondral transplantation; ACCT, autologous costal chondral transplantation; ACCI, autologous costa‐derived chondrocytes implantation; OCDCH, osteochondritis dissecans of the capitulum humeri; OLT, osteochondral lesions of the talus; TMC joint, trapeziometacarpal joint.

TABLE 2.

Summary of clinical studies on autologous costa‐derived grafts implantation.

Site	Study	Grafts	Patients and lesions.	Outcomes and main findings
Interphalangeal joint	Hasegawa et al. 33	ACCT, ACOT	Seven joints in five patients.	Two joints, using ACCT, resulted in bony ankylosis due to necrosis of the grafted cartilage. Five joints treated by ACOT obtained satisfactory bony union and range of movement.
	Sato K et al. 39	ACOT	30 joints in 29 patients	All implanted grafts resulted in bone union with the mean period of 58 days. Good clinical function. No major complications.
	Sato K et al. 40	ACOT	17 joints in 16 patients.	The mean increased arc of motion was 45°. Histologic examinations of the implanted cartilage 6 months after surgery revealed viable chondrocytes.
	Sato K et al. 41	ACOT	23 joints in 23 patients.	Significant improvement in active finger extension/flexion.
Wrist	Sandow 19	ACOT	22 joints in 22 patients. Deficiency of the proximal pole of the scaphoid.	Improvement of wrist function in all patients with increased motion, improved grip strength and less pain.
	Tropet et al. (2012) 42	ACCT	100 thumbs in 82 patients. Partial trapeziectomy.	The length of the thumb ray was preserved. Complication rate was 10.3%. No intracarpal deformities and no sign of graft wear.
	Obert et al. 43	ACCT	Seven patients. Malunion of the distal radius.	Pain‐free in daily activities with improved functional score and wrist strength.
	Obert et al. 44	ACCT	29 patients. The radiocarpal joint.	Two‐thirds of the patients had excellent or good results. Graft union was achieved in all cases. No graft resorption or necrosis. Histological analysis showed the vitality of the graft.
Elbow	Sato et al. 45	ACOT	Two patients. OCDCH.	The range of motion improved, and the patients no longer experienced pain 2 years after surgery. Radiographs showed bony union between the graft and the host.
	Shimada et al. 17	ACOT	26 patients. OCDCH.	All patients had rapid functional improvement and returned to their former activities. Osseous union of the graft on radiographs was obtained within 3 months in all patients.
	Nishinaka et al. 46	ACOT	22 patients. OCDCH.	All patients achieved rapid functional improvement and returned to their former sports activity levels. The mean total arc of motion, elbow extension, and elbow function scores were improved significantly.
	Sato et al. 31	ACOT	72 patients. OCDCH.	The mean elbow range and mean clinical rating score increased significantly. Most patients’ overall clinical score‐based assessment was excellent or good.
Knee	Gigante et al. 15	ACCT	One patient. A focal cartilage defect in patella.	No follow‐up outcomes.
	Yoon et al. 50	ACCI	Six patients. Full‐thickness cartilage lesions of trochlear, lateral or medial femoral condyle.	Significant improvements were seen in all clinical scores from preoperative baseline to the 5‐year follow‐up.
	Yoon et al. 34	ACCI	20 patients. Chondral defect of trochlear or femoral condyle.	The improvement of clinical and imaging scores and proportions of complete defect repair and complete integration in the CCP‐ACI group were greater than in the microfracture group at 48 weeks.
Hip	Zhang et al. 47	ACCT, ACOT	One patient. Osteochondral lesion of the femoral head.	The function of the hip joint improved significantly 3 months after surgery.
	Zhang et al. 16	ACCT	20 patients. Osteochondral lesion of the femoral head.	Significant improvement in clinical function and imaging evaluations. The ACCG demonstrated magnetic resonance properties very similar to hyaline cartilage.
Ankle	Wei et al. 48	ACOT	Five patients. Cystic osteochondral lesions of the talus.	The main clinical function indexes improved significantly. The biopsy of the surviving grafts showed plenty of hyaline cartilage matrix and scattered chondrocytes. No major severe complications were reported.
	Leung et al. 49	ACCT	One patient. A trimalleolar fracture concurrent with osteochondral lesions of the talus.	The VAS pain score was 0, and the American Orthopedic Foot and Ankle Society Score improved to 97 three years after surgery. CT images showed that the graft formed a relatively smooth articular surface with the surrounding bone.

Abbreviations: ACCI, autologous costa‐derived chondrocytes implantation; ACCG, autologous costal cartilage graft; ACCT, autologous costal chondral transplantation; ACOT, autologous costal osteochondral transplantation; CCP‐ACI, costal chondrocyte‐derived pellet‐type autologous chondrocyte implantation; OCDCH, osteochondritis dissecans of the capitulum humeri.

Autologous Costal Chondral/Osteochondral Transplantation

Interphalangeal Joint

Following the promising outcomes of autologous costal perichondrium to repair the articular surface in the 1970s to 1990s, ³⁶ , ³⁷ , ³⁸ in 1992, Hasegawa and Yamano reported on the use of autologous costal osteochondral transplantation (ACOT) to reconstruct proximal interphalangeal articular cartilage defects. ³³ Sato, et al. reconstructed articular cartilage in 30 finger joints by arthroplasty using ACOT. ³⁹ They harvested the graft(s) from the fifth or sixth costal osteochondral junction ipsilaterally through a transverse submammary incision and shaped the contour and thickness of the cartilage to fit the defect of the recipient site. ³⁹ The mean time to bone union of the 17 implanted grafts was 58 days. There were no differences macroscopically, and the same scattered viable chondrocyte within the hyaline cartilage matrix histologically compared with the normal articular cartilage. ⁴⁰ The same team also reported the medium‐ and long‐term follow‐up outcomes of total finger joint arthroplasty using ACOT. ⁴¹ Twenty‐three patients had a satisfactory anatomical and biological reconstruction with ACOT and had achieved stable clinical improvement at an average follow‐up of 77 months. ⁴¹

Wrist

Autologous costal osteochondral transplantation is also used to repair articular defects of small joints in the wrist. Sandow (1998) harvested the osteochondral grafts from the fifth or sixth rib to reconstruct the proximal scaphoid, and 22 patients were treated with ACOT and attained satisfactory mechanical integrity of scaphoid and wrist motion. ¹⁹ In a retrospective study of 82 patients treated with partial trapeziectomy and ACCT for trapeziometacarpal osteoarthritis, the procedure helped restore the stability and strength of the thumbs, and the transplanted grafts were good and stable enough to resist mechanical stress and cartilage wear. ⁴² ACCT was effective in reconstructing the radiocarpal joint for posttraumatic intra‐articular malunion and arthrosis following distal radius fracture and yielded reliable and satisfactory clinical function and resurfacing of articular cartilage in seven patients. ⁴³ The costal grafts revealed satisfactory radiographic and histologic outcomes for posttraumatic or degenerative arthritis of the wrist, and there were no signs of resorption and necrosis. ⁴⁴

Elbow

With the expanded indications of ACOT, good results were also observed in the large joint of the upper limb, the elbow. ACOT was used to treat osteochondritis dissecans of the capitulum humeri (OCDCH) in two patients and yielded good clinical results, suggesting ACOT to be useful and beneficial to OCDCH repair. ⁴⁵ In a retrospective study of 26 males with full‐thickness articular cartilage lesions (diameter above 15 mm) for OCDCH, ACOT yielded satisfactory functional improvement, and osseous union and revascularization of grafts were observed within 3 months and 12 months postoperatively respectively. ¹⁷ Another retrospective study of 22 patients achieved similar excellent outcomes. ⁴⁶ Sato et al. (2018) clarified the favorable longer‐term clinical results of ACOT for advanced OCDCH with a mean defect of 2.1 cm² in adolescent and young adult athletes. ³¹ Complete union of the grafts was observed in all 72 patients 3 months after surgery, and the average time to return to their former sport without any limitation was 5.8 months. ³¹

Knee and Hip

The application of ACOT and ACCT to repair the cartilage of weight‐bearing joints of the lower extremity is relatively recent compared with their application in the upper limb. Gigante et al. (2018) described one case using the autologous costal cartilage graft with perichondrium to repair full‐thickness chondral defects in the patella. ¹⁵ Zhang et al. (2018) first reported the application of ACOT and ACCT (or autologous costal cartilage graft [ACCG]) in the osteochondral lesions of the femoral head following traumatic osteonecrosis, and the short‐term results demonstrated improvement in clinical function. ⁴⁷ Recently, they reported a single‐arm prospective study of 20 patients treated with ACCT for large osteochondral lesions (size above 3 cm²) of the femoral head. ¹⁶ The clinical function achieved significant improvement at both 12 and 36 months postoperatively. ¹⁶ Complete integration of the grafts with bone was obtained in all patients at 12 months postoperatively, and the costal grafts showed very similar magnetic resonance properties to normal articular hyaline cartilage. ¹⁶

Ankle

Symptomatic cystic osteochondral lesions of the talus (OLTs) are challenging clinically. In 2023, Wei et al. reported ACOT for the treatment of cystic OLTs (Figure 4). ⁴⁸ All five patients had achieved satisfactory clinical recovery at 12 months postoperatively. ⁴⁸ Clinical function scores (numerical rating scale for pain, Tegner score, American Orthopedic Foot and Ankle Society Score, and Foot and Ankle Ability Measure) and radiographic and histological images demonstrated the safety and efficacy of ACOT for OLTs. ⁴⁸ There were no severe complications reported at the 12 month follow‐up. ⁴⁸ In 2023, the same team initiated a randomized controlled trial (NCT05942430) to evaluate whether ACOT can achieve better clinical outcomes and cartilage repair quality with lower donor site morbidity than autologous osteoperiosteal transplantation in the treatment of Hepple Stage V talar osteochondral lesions. In addition to the repair of the femoral head, Zhang and his team also applied ACCT technology to treat a patient with OLTs combined with a trimalleolar fracture. ¹⁶ , ⁴⁹ Three years after surgery, fusion of the costal cartilage with the talus bone bed and progressive endochondral ossification at the graft–bone interface were observed. ⁴⁹

FIGURE 4.

Autologous costal osteochondral transplantation for cystic osteochondral lesions of the talus. The autologous costal osteochondral junction of the fifth or sixth lib is exposed and harvested. The graft is trimmed, and holes are drilled into the bone part. The graft is inserted into the osteochondral defect area.

Autologous Costa‐Derived Chondrocyte Implantation

Given the limited capacity for intrinsic self‐healing and repair of articular cartilage, ³ providing additional chondrocyte is a feasible treatment. Yoon et al. reported seven patients with full‐thickness cartilage lesions treated with costal chondrocyte‐derived pellet‐type autologous chondrocyte implantation (CCP‐ACI). ⁵⁰ Cartilage specimens (approximately 500 mg) were harvested from the eighth, ninth, or 10th costa, and then costal chondrocyte were isolated and expanded in vitro, followed by three‐dimensional pellet culture to prepare the CCP‐ACI. ⁵⁰ The patient‐derived costal chondrocyte pellets showed lacunae‐occupied chondrocytes surrounded by glycosaminoglycan and type II collagen‐rich extracellular matrix, with similar histological characteristics to hyaline cartilage. ⁵⁰ During the 5‐year follow‐up, no serious adverse events occurred as a result of the procedure, and the overall clinical outcomes were good and acceptable with significant improvements. ⁵⁰ Recently, the same team reported a prospective randomized study comparing CCP‐ACI with microfractures, ³⁴ The CCP‐ACI group yielded better cartilage tissue repair outcomes on MRI and functional scores than the microfracture group at 24 and 48 weeks postoperatively. ³⁴ Further, the CCP‐ACI group achieved higher rates of complete defect repair and complete integration than the microfracture group at 48 weeks postoperatively, with rates of 20% vs. 15% and 85% vs. 30% respectively.

Risks and Strategies in Costal Chondral/Osteochondral Graft(s) Harvest

Risks

In applying costa‐derived graft(s), risks at the donor site are a priority for consideration, especially serious donor‐site mobility such as pneumothorax and intercostal neuralgia. ²⁸ A systematic review examined the rates of donor‐site complications associated with ACCT in rhinoplasty and reported that the overall pooled rate was 3.2% (n = 1545). ⁵¹ Scar‐related problems (2.9%) were the most frequent long‐term donor‐site complication, and no case of chest wall deformity was reported. ⁵¹ Other donor‐site complications included seroma (0.6%), infection (0.6%), severe donor‐site pain (0.2%), pleural tear (0.6%), and pneumothorax (0.1%); these rates were lower than surgeons feared. ⁵¹ Another comparative study (n = 600) revealed that donor‐site morbidity was lower with rib than with iliac crest, and the worrying serious complications did not appear, including pneumothorax, intercostal neuralgia, and chronic chest wall pain. ²⁸ Loisel et al. (2018) reported 136 cases of ACCT or ACOT for joint reconstruction of the upper extremity and that donor‐site discomfort (pain during sneezing or laughing) was observed in one‐third of patients. ⁵² Sato et al. reported that there was no more pain in the donor site after 2 to 3 days postoperatively. ⁵³ To sum up, the rate of donor‐site complications of ACCT or ACOT is low, acceptable, and controllable, and surgeons’ skills and accumulated experience can help reduce the risks.

Strategies

For risk management and practical reasons, some procedures and surgical techniques should be taken into consideration. First, preoperative chest computed tomography is preferred to evaluate the targeted costal cartilage, including its width, thickness, length, and degree of calcification. The area of the intended surgical incision should be marked on the body surface above the targeted rib. ⁵² Second, the size and volume of costal grafts are determined by the lesion (recipient site), and much more attention should be paid to the intercostal nerve and blood vessels during harvesting by using finely shaped surgical tools. Third, it is vital to access the integrity of the pleura intraoperatively. The universal technique is to observe bubbling after filling the donor site with solution (like saline) and applying positive pressure ventilation or the Valsalva maneuver. ⁵¹ Fourth, local injection of painkillers (like bupivacaine) intraoperatively or a preventive local nerve block can help control postoperative local pain in the donor area. ⁵⁴ , ⁵⁵ Fifth, regular postoperative X‐rays or CT scans are recommended to assess the healing status of the bone. MRI can be used to assess the survival and changes of the cartilage. Finally, rehabilitation training under the guidance of clinicians and rehabilitation therapists is necessary and is conducive to the safe, functional recovery of patients.

Prospect of Costal Cartilage‐Derived Autografting

Based on the strong support of current clinical studies related to autologous costal cartilage grafts, there will be more clinical applications and new technologies derived in the future. For example, due to the high plasticity and large supply of autologous costal cartilage, it can be spliced, trimmed, and combined for the repair of larger areas and volumes of articular and osteochondral defects. The cutting‐edge technology of biomaterial fabrication (e.g., three‐dimensional bioprinting and microspheres), the crushed autologous costal cartilage, can provide a more convenient and minimally invasive treatment for the above‐described diseases. Heterologous costal cartilage acellular matrix might also be a future direction of exploration.

Summary

Given the unique properties of costal cartilage and bone and their good characteristics as grafts for articular cartilage repair, more and more clinical applications are emerging, from small to large joints, from the upper to lower limbs, and from non‐weight‐bearing to weight‐bearing joints. The rate of donor‐site complications of ACCT or ACOT is low, acceptable, and controllable, and some skills and accumulated experience can help reduce the risks in costa‐derived graft(s) harvest. Costal cartilage‐derived autografting is a promising technique and might be an ideal option for articular chondral lesions with or without subchondral cysts. In future, there will be more clinical applications and indications and derivative technologies related to autologous costal cartilage. More high‐quality clinical studies are also urgently needed to help us understand the clinical value of such technologies.

Funding Supporting

This work was supported by Guangzhou clinical characteristic technology (2023–2025) and Other Business Development Expenditure Including Livelihood Subsidies in 2021 (Overseas Masters).

Conflict of Interest Statement

Yuxuan Wei, Hao Guo, Zhuhong Chen, Nian Sun, and Canjun Zeng declare no conflict of interests.

Author Contributions

Yuxuan Wei: Wrote and edited the manuscript. Hao Guo: Wrote and edited the manuscript. Zhuhong Chen: Wrote and edited the manuscript. Nian Sun: Wrote and edited the manuscript. Canjun Zeng: Conceptualized, wrote, and edited the manuscript. All authors listed meet the authorship criteria according to the latest guidelines of the International Committee of Medical Journal Editors, and all authors are in agreement with the manuscript.