Osteochondral Autograft Transplantation Coupled With Platelet-Rich Plasma and Hyaluronic Acid Injections Can Yield Favorable Outcomes in Patients With Osteochondral Lesions of the Talus

Purpose

To evaluate the outcomes of patients who had osteochondral lesions of the talus treated with osteochondral allograft transplants combined with platelet-rich plasma (PRP) and hyaluronic acid (HA).

Methods

We aimed to investigate the outcomes of patients who underwent osteochondral autograft transplantation surgery (OATS) from 2015 to 2022. The inclusion criteria for patients to undergo OATS included a defect size greater than 5 mm and failure of conservative management. The preoperative and postoperative visual analog scale (VAS) and American Orthopaedic Foot & Ankle Society (AOFAS) scores were recorded and subsequently analyzed using a paired t test. We also performed cohort-specific analyses that included the minimal clinically important difference, patient acceptable symptom state, and substantial clinical benefit. PRP injections were administered at 8 weeks postoperatively and were given every 2 weeks, for 3 total injections. HA was injected once every 6 months for the following 2 years. The minimum follow-up time was 2 years.

Results

At the 12-month follow-up, all 19 patients reported a mean increase in the VAS score of 33.40 (95% confidence interval, 30.9-35.8). The average age was 31 years, and there were 12 male and 7 female patients. Of the 19 patients, 17 reported no restriction of motion, whereas the other 2 patients reported some restriction of dorsiflexion. Ankle function based on the AOFAS scoring system showed good to excellent results in 18 of 19 cases (94%), with no long-term donor-site morbidity and a mean increase of 37.49 (95% confidence interval, 34.7-40). Hardware removal of lag screws was conducted at 12 months after initial surgery; all cases resulted in union of the malleolar osteotomy. The average follow-up time was 3 years.

Conclusions

Combining OATS with PRP-HA injections can yield promising results for patients with osteochondral lesions of the talus, showing significant improvement in VAS and AOFAS scores postoperatively.

Level of Evidence

Level IV, therapeutic case series.

Osteochondral lesions of the talus (OCLTs) represent a challenging orthopaedic condition with potentially significant morbidity. They are characterized by disruption of the articular cartilage and underlying subchondral bone in the ankle joint. The location of OCLTs is mapped by the Raikin grid classification, which divides the talar dome into 9 zones. ^, Studies suggest that defect size and diameter (as seen on magnetic resonance imaging [MRI]) are important determinants for conservative treatment failure; lesions larger than 10 mm in diameter are less likely to respond to treatments such as microfracture or drilling and may require more intensive procedures such as osteochondral autograft transplantation surgery (OATS). ^,^,

Regardless of defect size, first-line treatment of OCLTs consists of nonoperative conservative management, which includes nonsteroidal anti-inflammatory drugs, rest, immobilization, and physical therapy. ^, For smaller, nondisplaced lesions, conservative management may lead to positive outcomes, not requiring surgery. Some evidence has supported the use of platelet-rich plasma (PRP) injections, along with nonoperative modification, as a form of adjunctive therapy; however, long-term studies of outcomes are lacking. ^,

Conservative treatment shows favorable clinical outcomes in patients with stage 1 or 2 OCLTs per the Berndt and Harty classification. ^,^, Surgical treatment is considered after failure of conservative management strategies or for Berndt and Harty stage 2 to 5 lesions and is broadly based on repair, regeneration, and replacement of the cartilage segment. ^,^,^, Cartilage repair and regeneration techniques include microfracture and autologous chondrocyte implantation, which is often considered after failed microfracture. Microfracture is indicated for lesions measuring less than 1 to 1.5 cm, whereas autologous chondrocyte implantation can be used for larger lesions. ^,^, Additional surgical treatment involving replacement of the defective cartilage with true hyaline cartilage, such as osteochondral autologous transplantation (e.g., OATS), is indicated for a defect size greater than 8 mm, failed reparative techniques, and stage 5 cystic lesions.

Surgical intervention is commonly required for lesions that fail conservative management and for larger lesions (>8 mm) or lesions associated with persistent symptoms because these are unlikely to resolve on their own and would require operative treatment, especially in adults. Surgical treatment options may include arthroscopy with the removal of loose fragments, debridement, bone marrow stimulation using a microfracture technique, or other surgical interventions such as chondroplasty, OATS (including mosaicplasty), or osteochondral allograft transplantation from a non-weight-bearing or less weight-bearing portion of the knee to the ipsilateral talus. ^,^,^,^,

The use of PRP as an adjunct to microfracture treatment of OCLTs has shown good outcomes across multiple studies. ^,^,^, Preclinical studies have shown promising results combining PRP with OATS; however, the evidence in clinical practice remains sparse. ^,^, The use of hyaluronic acid (HA) as an adjunct for the treatment of OCLTs when combined with microfracture has been described; however, no clinical studies have investigated the application of HA along with OATS or PRP plus HA along with OATS for the treatment of OCLTs.

The purpose of this study was to evaluate the outcomes of patients who had OCLTs treated with osteochondral allograft transplants combined with PRP and HA. We hypothesized that OATS with PRP-HA injections would yield favorable outcomes when treating OCLTs at a minimum 2-year follow-up.

Methods

The clinical, radiologic, and operative records of all patients treated for OCLTs by a single surgeon (L.N) from 2015 to 2022 at a single private center were reviewed retrospectively; this was not a consecutive series of all our patients with OCLTs. The diagnosis of OCLTs was based on clinical examination findings, along with preoperative radiographs and MRI scans of the ankle joint. Duration of symptoms and mechanism of injury, if any, were considered. Patient demographic characteristics, including age, sex, weight, and body mass index, were recorded ( Table 1 ). The visual analog scale (VAS) score and American Orthopaedic Foot & Ankle Society (AOFAS) score were also recorded preoperatively and at the 12-month follow-up.

Table 1

Patient Sex, Age, BMI, Date of Surgery, and Radiologic Classification

Patient	Sex/Age, yr	Year of Procedure	BMI	Lesion Location (9-Grid Scheme)	Defect Size, mm	Procedure	No. of Grafts Used	Stage
Patient	Sex/Age, yr	Year of Procedure	BMI	Lesion Location (9-Grid Scheme)	Defect Size, mm	Procedure	No. of Grafts Used	Berndt and Harty Radiographic Staging System	Hepple MRI Staging System
Patient 1	M/33	2019	28.4	3, 6	<8	Chondroplasty + OATS	1	2	2b
Patient 2	M/53	2019	30.1	4	<8	Chondroplasty + OATS + osteotomy	1	2	3
Patient 3	M/31	2019	24.8	4, 7	8-16	Chondroplasty + OATS + osteotomy	2	3	4
Patient 4	M/33	2020	21.9	4	<8	OATS + osteotomy	1	2	2b
Patient 5	M/25	2019	24.8	4	<8	OATS + osteotomy	1	2	2b
Patient 6	M/25	2016	25.4	4, 7	8-16	Chondroplasty + OATS + osteotomy	2	3	3
Patient 7	M/39	2017	33.7	4	<8	Chondroplasty + OATS + osteotomy	1	2	2b
Patient 8	M/23	2017	23.1	4, 7	8-16	Chondroplasty + OATS + osteotomy	2	3	3
Patient 9	M/34	2020	32.1	4	<8	Chondroplasty + OATS + osteotomy	1	2	2b
Patient 10	M/28	2018	32	4, 7	8-16	Chondroplasty + OATS + osteotomy	2	3	2b
Patient 11	F/24	2020	23	4, 7	<8	Chondroplasty + OATS + osteotomy	1	2	2b
Patient 12	F/23	2020	26	4, 7	8-16	Chondroplasty + OATS + osteotomy	2	3	3
Patient 13	F/21	2020	24.8	7	<8	OATS + osteotomy	1	2	2b
Patient 14	F/23	2019	25	4	<8	OATS + osteotomy	1	2	2b
Patient 15	F/51	2019	34.1	4, 7	8-16	Chondroplasty + OATS + osteotomy	2	4	4
Patient 16	F/31	2020	24.6	4, 7	8-16	Chondroplasty + OATS + osteotomy	2	3	3
Patient 17	F/45	2021	21	4, 7	8-16	Chondroplasty + OATS + osteotomy	2	3	2b
Patient 18	M/20	2022	32	4	8-16	Chondroplasty + OATS + osteotomy	2	3	3
Patient 19	M/27	2022	26.9	4	8-16	Chondroplasty + OATS + osteotomy	2	3	2a

BMI, body mass index; F, female; M, male; MRI, magnetic resonance imaging; OATS, osteochondral autograft transplantation surgery.

Preoperatively, the clinical evaluation also involved assessing the donor site and examining radiographs of the lateral femoral condyle for any signs of degeneration that could increase the risk of donor-site morbidity, such as joint space narrowing or irregular joint contours. ^, The talus and tibiotalar joint MRI scans were analyzed to assess the cartilage surface integrity and precisely locate the defect ( Figs 1 and 2 ). The lesion was localized using the Raikin anatomic 9-zone grid system ( Fig 3 ). Classification and staging of each patient’s preoperative imaging were completed using the Berndt and Harty radiographic system and the Hepple MRI system.

Image, AltText currently not available — Fig 1

The indications for patients to undergo OATS included a defect size greater than 5 mm. Patients with a defect size greater than 5 mm but less than 8 mm underwent OATS alone, whereas those with a defect size exceeding 8 mm received OATS with chondroplasty. We included patients who experienced acute trauma or who had chronic post-traumatic lesions, and none of the patients in our cohorts presented with OCLTs after an acute fracture. Additional inclusion criteria comprised the presence of ankle pain with a limited range of motion and failure of conservative management for a duration exceeding 6 months. We excluded patients younger than 18 years or older than 60 years and patients with a defect size less than 5 mm. We used the 5-mm cutoff because lesions less than 5 mm were considered too small for OATS and were instead treated with microfracture, which has been shown to achieve similar results for lesions of this size and is less invasive.

Surgical outcomes were thoroughly evaluated by comparing patients’ preoperative and postoperative scores after undergoing OATS. To assess how the procedure affected pain levels and functional recovery, a paired t test was used to analyze the changes in both the VAS score and the AOFAS score. A significance level of.05 (α) was chosen for all statistical tests. The analysis was conducted using SPSS software, version 26.0 (IBM, Armonk, NY). The institutional review board reviewed the study protocol and ensured that it met ethical standards, including informed consent, participant safety, and data privacy, according to the National Institutes of Health.

Initially, all patients underwent conservative management of OCLTs, including rest, casting immobilization, physical therapy, and nonsteroidal anti-inflammatory drugs for pain. ^, Patients who did not respond to this conservative approach were offered surgical intervention.

A diagnostic arthroscopy was performed before the surgical procedure to locate any impingement or loose bodies. Chondroplasty was performed arthroscopically through anteromedial and anterolateral portals to remove any free edematous debris or impinging tissue. Loose chondral or osteochondral fragments were removed, and a mechanical shaver was used to smooth the damaged cartilage and create a stable articular surface. For medial lesions for which a medial approach was required, 2 small screw holes were predrilled to aid in malleolar reduction after the procedure. OATS was then performed using an open approach under spinal anesthesia. Osteotomy was planned based on the location of the lesions. For medial lesions (anatomic locations 4 and 7 on the Raikin grid), a longitudinal incision was made to the projection of the medial malleolus and extended posteriorly and distally to expose the underlying surface. A medial malleolar osteotomy was then performed ^,^, ( Fig 4 ). For lateral defects, a longitudinal incision was performed directly over the lateral malleolus. Because of the anterolateral location of the lesion, access was obtained without the need for a tibial osteotomy; only a fibular osteotomy was required, and the tibia was distracted. ^,^, In a plantar-flexed position, the anterolateral capsule was resected, and the joint was subluxated to expose the lesion. ^,^, The lesions were prepared with debridement of the affected area along with the removal of any loose cartilage.

The autograft OATS 2.0 Set (Arthrex, Naples, FL) was used to estimate the size and number of grafts required for transplantation. A preoperative radiograph of the knee was obtained to verify the integrity of the joint and donor site ( Fig 5 ). Grafts were obtained through an open surgical technique from the periphery of the ipsilateral lateral femoral condyle of the knee. An incision was made along the superolateral border of the patella, and a small arthrotomy was performed. Two surgical retractors were positioned to expose the sulcus terminalis and to harvest the graft. A set of sizers with diameters of 4.5, 6, 8, and 10 mm were used to determine the defect size precisely. A donor tube harvester was assembled to match the sizers, and it was gently driven into the subchondral cartilage of the ipsilateral lateral femoral condyle to a depth of 15 mm using a mallet. After reaching the appropriate depth, the harvester was rotated before being driven out with the donor cartilage inside.