Outcomes of Periosteal-Iliac Bone Autografting with Platelet-Rich Plasma in Patients with Hepple V Talar Lesions: A Retrospective Study

Introduction

Osteochondral lesion of the talus is the most prevalent form of articular cartilage injury in the ankle, accounting for approximately 4% of all osteochondral lesions throughout the body [1,2]. Osteochondral lesions of the talus are commonly observed in patients with ankle trauma and avascular necrosis. It has been documented that up to 6.5% of individuals who have experienced an ankle sprain or fracture develop osteochondral lesions of the talus, which commonly affect the posteromedial and anterolateral domes of the talus [3–6]. Currently, the classification of talar osteochondral lesions in clinical practice follows primarily the Hepple classification system, which is based on the severity of articular cartilage damage and underlying bone injury in the ankle joint, as assessed by magnetic resonance imaging (MRI) [7]. In the Hepple classification system, stage I is a simple articular cartilage injury; stage II is cartilage damage accompanied by subchondral bone lesions, with or without bone marrow edema; stage III is characterized by separation of the cartilage from the body of the talus without displacement; stage IV is separation and displacement of the cartilage from the talus body; and stage V is cartilage injury combined with subchondral bone cyst formation [8]. Given that these lesions affect both the articular cartilage and the subchondral bone, they are susceptible to inducing severe symptoms, including pain, joint swelling, stiffness, restricted mobility, and, potentially, traumatic osteoarthritis. These issues significantly impair patient quality of life.

Currently, symptomatic lesions typically require surgical intervention, including excisional curettage, curettage and drilling or microfracture, allogeneic or autologous osteochondral transplantation, and autologous chondrocyte implantation [9–12]. Periosteal iliac bone autografts are typically harvested from the iliac crest as cylindrical cortical-cancellous bone blocks with intact periosteum and are precisely transplanted to the defect site of the talus. The core advantage of the procedure lies in the simultaneous repair of the dual-layer structure of bone and cartilage, thereby delaying the progression of traumatic arthritis [13]. However, the regenerative capacity of joint cartilage is exceedingly limited; therefore, the cartilage surface rarely heals itself under normal conditions [14]. In particular, injuries to the talar cartilage, such as those characterized in Hepple stage V, pose a significant challenge for numerous physicians. For the purpose of increasing the quality of the cartilage repair tissue, the use of platelet-rich plasma (PRP) is gradually increasing in clinical practice [15]. At present, it has been confirmed that PRP has a good therapeutic effect on osteoarthritis, promoting wound healing, nonunion, muscle injury, and tendinopathy [16–18]. Petrera et al [19] studied the effect of PRP on the histological, biochemical, and biomechanical properties of tissue-engineered cartilage and found that the presence of PRP enhanced cartilage formation in vitro, increased glycosaminoglycan content, and improved compressive strength while maintaining the characteristics of the hyaline phenotype. Mifune et al and Milano et al discovered in animal experiments that PRP exerts a positive influence on promoting cartilage repair and regeneration [20,21].

Given its promising cartilage regeneration properties, PRP offers a novel approach to treating Hepple type V talus osteochondral injuries. Therefore, in this retrospective study, we aimed to evaluate outcomes from periosteal-iliac bone autografting combined with intra-articular PRP in 63 patients treated for Hepple V osteochondral lesions of the talus.

Material and Methods

ETHICS STATEMENT:

The study was approved by the ethics committee of our hospital (2019071), who waived the requirement for informed consent, since this was a retrospective study and the data were anonymous.

INCLUSION AND EXCLUSION CRITERIA:

We analyzed 63 patients with osteochondral lesions of the talus who had been admitted to our department and received treatment by periosteum-iliac bone autografting combined with intra-articular PRP from October 2019 to September 2022. The inclusion criteria were as follows: patients aged between 18 and 65 years; chronic ankle pain accompanied by cystic osteochondral lesions of the talus, confirmed by ankle joint magnetic resonance imaging (MRI); unilateral Hepple V medial talar cartilage lesion, as shown on MRI; and individuals willing to voluntarily participate in the clinical trial and provide signed informed consent. The exclusion criteria included a history of talar fracture or ankle joint infection, severe ankle osteoarthritis or traumatic arthritis, long-term smoking, diabetes, which could potentially impact the prognosis, and follow-up for less than 12 months.

PREOPERATIVE MANAGEMENT:

A researcher unaffiliated with the clinical treatment of patients used a random number table to assign patients into 2 groups: the control group, and the observational (PRP) group. The researcher then collected information including age, sex, lesion location, lesion size, duration of follow-up, and duration of symptoms. All patients underwent preoperative anteroposterior and lateral radiographs, computed tomography (CT), and MRI examination of the ankle, including measurements of the diameter and area of the cystic lesion (Figure 1). The surgeries were performed exclusively by 2 experienced orthopedic surgeons specializing in foot and ankle procedures, each with over 10 years of clinical expertise. Postoperative functional outcomes at follow-up were evaluated by an experienced orthopedic surgeon who was blind to the patient grouping, to ensure an impartial and comparable evaluation.

PRP SCAFFOLD PREPARATION:

The PRP scaffolds were prepared using the WEGO PRP preparation kit (WEGO Ltd, Shandong, China). Briefly, approximately 50 mL of peripheral venous blood was aseptically collected from the patient’s antecubital vein and transferred into the designated centrifuge tube. The sample was then centrifuged at 2000 revolutions per min for 10 min using the company’s portable centrifuge device. Following the first centrifugation, the lower red blood cell layer was carefully aspirated and discarded. The remaining supernatant, containing platelets and plasma, was subjected to a second centrifugation under the same conditions. After the second spin, the upper plasma layer was removed, leaving approximately 5 mL of the lower white flocculent (buffy coat) sediment, which contained the concentrated PRP. Finally, PRP was activated by the addition of a 10% calcium chloride solution. This standardized procedure yielded approximately 4 to 5 mL of PRP that met the required quality specifications.

SURGICAL PROCEDURE:

All the surgeries were done under spinal anesthesia, and a tourniquet was used in all the cases. The skin was routinely disinfected with iodine and alcohol and covered with a sterile surgical sheet, and an 8-cm-long curved incision was made on the anteromedial side of the affected ankle joint. The skin and subcutaneous and soft tissue were cut layer by layer to protect the great saphenous vein and expose the medial malleolar. After positioning the osteotomy line by a Kirschner guide wire, the medial malleolar osteotomy was performed using an oscillating saw, with an osteotome for the final cut. Next, the damaged area of the medial dome of the talus was exposed; the cartilage was scratched and stripped; the necrotic cartilage was cleaned; the size of the lesion was assessed; the annular bone knife with appropriate diameter was selected; the vertical articular surface was drilled into the subchondral bone; the damaged tissue and cyst, cystic cavity, and surrounding sclerosed bone were removed; and microfracture was performed using a Kirschner wire to create the bone groove (Figure 2A). The ipsilateral anterior superior iliac crest was exposed, and the periosteum was retained. The bone plug with periosteum was harvested vertically from the bone surface using a trephine of the same diameter. The diameter of the bone plug was equal to the diameter of the talus groove, and the length was slightly shorter than the notch (Figure 2B). A small amount of cancellous bone was placed at the base of the talus gap, and the bone plug was pressed into the gap to make the embolus level with the subtalus (Figure 2C). At this point, the periosteum on the bone plug was basically parallel to the surface of the talus cartilage (Figure 2D), the medial malleolus osteotomy block was reduced after the articular surface was matched at the movable ankle joint, and 3 to 4 headless hollow bone screws were screwed for compression and fixation. In the PRP group, upon completion of the surgical procedure, the pre-prepared autologous PRP was gently agitated under aseptic conditions to ensure homogeneous mixing. Using a sterile syringe, 5 mL of the uniformly mixed PRP solution was accurately administered into the ankle joint cavity via the medial ankle approach, while a portion of the PRP was applied topically to the bone graft site. Patients in the control group did not receive PRP administration. Both groups subsequently underwent standard surgical wound closure using layered sutures, thereby completing the operative procedure.

POSTOPERATIVE MANAGEMENT AND FOLLOW-UP:

Postoperatively, the patients were encouraged to move the toes and ankles frequently in the immediate postoperative period, following the principle of early activity and late weight-bearing. On the second postoperative day, patients began isometric muscle contraction and interphalangeal joint flexion and extension activities on their own. The sutures were removed 2 weeks later, and the patients began plantar flexion, dorsiflexion, inversion, and valgus activities of the ankle. Partial weight-bearing was allowed for 6 weeks after surgery, but vigorous activities were prohibited. After 12 weeks, patients were permitted to walk with full weight-bearing and gradually return to normal life or low-intensity physical activity.

OUTCOME MEASURES:

The basic data of all patients were collected. All patients were followed up clinically and radiologically before surgery, at 3 months, 6 months, and 12 months after surgery, and at the last follow-up. A physical examination was performed, and anteroposterior and lateral radiographs, CT, or MRI of the ankle were taken at each follow-up evaluation (Figure 3), to observe the bone healing at the osteotomy of the medial malleolus and the bone healing of grafts in the injured area of talus cartilage. Clinical outcome measures were visual analog scale (VAS) pain scores, measured during rest, walking, and running. The Short Form 36 (SF-36) questionnaire [12] was used to assess patient quality of life. Functional outcomes were evaluated according to American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores and range of motion (ROM) during follow-up.

STATISTICAL ANALYSIS:

SPSS 24.0 software (IBM Corp, Armonk, NY, USA) was used for statistical analysis. Categorical data were statistically analyzed using the chi-square or Fisher exact test (n<40 or t<1). Data normality was tested using the Shapiro-Wilk test. Continuous data with a normal distribution were expressed as mean±standard deviation. Preoperative and postoperative values (AOFAS ankle-hindfoot scores, VAS scores, SF-36 scores, and ROM) were compared by a paired t test. A P value <0.05 indicated a statistically significant difference.

Results

COMPARISON OF GENERAL INFORMATION BETWEEN THE 2 GROUPS:

Ultimately, 63 patients, including 39 men and 24 women, with an average age of 42.8 years (range, 28–61 years), were followed up for an average of 19 months (range, 12–30 months) and were included for final analysis. The results presented in Table 1 show there were no statistically significant differences between the control and PRP groups with respect to age, sex, lesion side, symptom duration, lesion size, and duration of follow-up (all P>0.05). After surgery, no patients experienced any soft tissue complications, such as wound infection or skin necrosis. Furthermore, there were no instances of internal fixation failure, osteotomy end nonunion or malunion, or other complications during the follow-up period.

COMPARISON OF CLINICAL OUTCOME BETWEEN THE 2 GROUPS:

The VAS (during rest), VAS (during walking), VAS (during running), SF-36, and ROM of both groups significantly improved postoperatively (all P<0.001). There were no significant differences in the preoperative values of these variables between the 2 groups (all P>0.05, Table 2). In addition, as shown in Table 2, all clinical values in the PRP group were significantly improved postoperatively, compared with those in the control group (all P<0.05).

COMPARISON OF AOFAS OUTCOMES BETWEEN THE 2 GROUPS:

As shown in Table 3, according to the AOFAS scoring system, good-excellent outcomes were reported in 28 cases (93.33%) in the PRP group and in 29 cases (87.88%) in the control group. Although the AOFAS scores were slightly higher in the PRP group, no significant differences were found between the groups (91.2 vs 88.6, P=0.12).

Discussion

In the present study, we analyzed 63 patients with Hepple V osteochondral lesions of the talus with subchondral cysts. Our study results showed that AOFAS scores, SF-36 scores, and ROM significantly improved postoperatively, and there were no serious complications. Due to inflammatory reaction, osteochondral lesions of the talus commonly cause severe and persistent pain, especially after activity, which can interfere with the patient’s daily life. Consequently, our findings indicate that VAS scores associated with periosteum-iliac bone autografting were significantly improved during rest, walking, and running, exhibiting notable benefits.

Osteochondral lesions of the talus accompanied by subchondral bone cysts cause chronic ankle pain and present a significant treatment challenge with a poor prognosis, posing difficulties for foot and ankle surgeons. Gu et al [23] illustrated that for Hepple stage V osteochondral lesions of the talus, treatment involving cancellous bone grafts and PRP scaffolds could be a safe and efficacious approach. Autologous osteochondral transplantation typically uses osteochondral columns from the ipsilateral knee to repair injuries, ultimately resulting in the formation of hyaline cartilage that possesses excellent biomechanical properties. Nonetheless, donor-site morbidity remains a concerning complication [24]. The currently published percentages of donor-site morbidity following knee-to-talar autologous osteochondral transplantation vary from 0% to 54.5% [25–27]. Based on a biomechanical cadaver model of the knee joint, Garretson et al [28] concluded that harvesting from a weight-bearing area involving more than 2 bone columns with diameters greater than 5 mm will increase the likelihood of pain in the donor site. In addition to knee pain, several other symptoms have been reported, including stiffness, instability, discomfort, and effusion. The iliac region offers an abundant source of donor bone and is easy to access surgically, allowing for the harvest of larger diameters and a greater number of bone columns. The autologous cancellous iliac bone exhibits a biological structure similar to that of the normal talus, thereby effectively preventing rejection reactions. Additionally, it possesses robust cartilage regeneration capabilities, which facilitate the early healing of talus cartilage injuries. Furthermore, its application can prevent the recurrence of talus cysts and maintain the height and stability of the grafted bone column [29]. Therefore, the authors opted for autogenous iliac bone grafting, and the results indicated that the procedure is secure, yields favorable clinical outcomes, exhibits a minimal rate of complications, and enhances postoperative pain relief and functional improvement to a certain extent.

PRP is a highly concentrated plasma derived from whole blood that contains abundant growth factors. It is extensively used in the treatment of various articular cartilage injuries, to alleviate pain and enhance joint function [30]. PRP not only provides a concentrated source of nutrition for tissue repair but also creates an optimal environment for enhanced and expedited tissue regeneration. Jazzo et al [31] investigated the efficacy of PRP injection in treating osteochondral lesions of the talus, revealing significant improvements in pain levels and functional evaluations. Fukawa et al [32] also studied the treatment of ankle osteoarthritis by intra-articular injection of PRP and observed that the greatest reduction in ankle pain was achieved after 12 weeks of treatment. In the present study, PRP was applied in conjunction with cancellous bone grafting. The inherent biological properties of PRP were harnessed to enhance the biological milieu surrounding the lesion, stimulate chondrocyte differentiation, and foster the development of cartilage on the lesion’s surface. The results demonstrated a significant alleviation of ankle pain, substantial recovery in ankle function compared with preoperative levels, and an improvement in patient quality of life.

This study has limitations. First, the sample size was relatively small (type II error). Therefore, further studies with larger samples are needed to obtain overall clinical data. Moreover, it was very difficult to assign all patients to only 1 surgeon in our hospital. Therefore, the differences in surgeons’ performances might have decreased the ability to extrapolate the results of this study.

Conclusions

Autologous periosteum-iliac bone combined with intra-articular PRP bone grafting was used for the treatment of talus Hepple type V osteochondral lesions. PRP as an adjuvant therapy, under the main treatment method of periosteum-iliac bone transplantation, improved the reliability of periosteum-iliac bone transplantation, shortened the bone healing time, accelerated the reconstruction of cartilage tissue, and reduced complications.