Subchondroplasty of the Ankle and Hindfoot for Treatment of Osteochondral Lesions and Stress Fractures: Initial Imaging Experience

Complications Following Intraosseous Injections of Calcium Phosphate Bone Cement in Subchondroplasty

An alternative approach to the major problem of osteoarthritis that has begun to pique the interest of researchers focuses on the pathology of the subchondral bone, its constant cross-talk with the articular cartilage, and its interaction with the joint. The presence of bone marrow lesions, detectable on MRI scans, has proven to be a cause of pain as well as a predictor of the progression of degenerative changes. Subchondroplasty is a relatively new surgical procedure for the treatment of these lesions, in which injectable calcium phosphate bone cement is infused into the affected area percutaneously, under fluoroscopic guidance. In its use as a synthetic scaffold, calcium phosphate bone cement exhibits considerable osteoconductivity, bioabsorbability, and low toxicity, thus showing great potential for restoring subchondral biomechanical properties through structural remodeling. Although published results appear quite promising, there are certain complications that the surgeon should be aware of. We reviewed the published data regarding complications of the procedure, highlighting possible causes according to these data, and suggesting safety measures. Avascular necrosis of the talus is the most reported concern. Postsurgical pain, infection, and continuous wound drainage due to bone substitute material extravasation to the joint or soft tissue are also mentioned, necessitating further standardization of the procedure. There are no reports of permanent postoperative disability or fatal outcomes.

A Retrospective Study Assessing the Clinical Outcomes After Cheilectomy and Subchondroplasty for Hallux Rigidus

Introduction Hallux rigidus (HR) refers to osteoarthritis of the first metatarsal phalangeal joint, resulting in stiffness, pain, and limitation in daily function. Surgery of HR is indicated in those who have failed a trial of non-operative management and is typically divided into joint-preserving (JP) and joint-sacrificing procedures. Cheilectomy is the most commonly practiced JP procedure, often done in conjunction with associated procedures for HR. Our paper aims to report the clinical outcomes after cheilectomy and cheilectomy done with subchondroplasty (SCP) performed for HR. Methods All patients who underwent cheilectomy for HR between 2017 and 2022 were identified and had their outcomes evaluated at the time of this review. The patients had their pre-operative radiographs and clinical and operative notes analyzed for the grading of HR. Functional outcomes were assessed with the use of the visual analog scale (VAS) and American Orthopaedic Foot and Ankle Society (AOFAS) scores, as well as comparing the pre-operative and post-operative degree of dorsiflexion of the affected first metatarsophalangeal joint. This study was approved by the SingHealth Institutional Review Board (IRB) Institution with approval number 2021/2629. Results A total of 19 patients and 20 feet were included in our study at a mean follow-up of 29.8 months. There was an increase in dorsiflexion of the first MTP joint by 27.2 degrees (p-value = <0.0001). Patients who underwent cheilectomy alone (Group 1) had a mean improvement in VAS scores of 5.46 (p-value = <0.0001). Patients who underwent SCP of the first metatarsal head along with cheilectomy (Group 2) had an improvement in VAS scores by 5.78 (p-value = 0.0007). There was a mean improvement in AOFAS scores of 25.6 (p-value = <0.0001) for patients in Group 1. Patients in Group 2 had a mean improvement in AOFAS scores of 31.0 (p-value = 0.0003). Conclusion Both cheilectomy and cheilectomy performed with SCP for HR show good outcomes at short-term follow-up (mean 29.8 months). Cheilectomy is a viable alternative to arthrodesis for the surgical treatment of HR even in patients with higher grades. The use of SCP should be further explored as an adjunct in the surgical treatment of HR.

Management of Subchondral Lesions in the Foot and Ankle

The treatment of subchondral lesions is an area with limited focus within the foot and ankle literature. The literature has shown an association between disruption of the subchondral bone plate and the formation of subchondral cysts. The primary causes of subchondral lesions are acute trauma, repetitive microtrauma, as well as idiopathic means. Evaluation of these injuries should be done carefully and often requires advanced imaging including MRI and computed tomography. Treatment does vary depending on the presentation of the subchondral lesion with or without the presence of an osteochondral lesion.

Avascular Necrosis of the Talus After Subchondroplasty

BACKGROUND

Subchondroplasty (SCP) is a relatively new procedure, developed in 2007 for the treatment of bone marrow lesions (BMLs), that has shown promising results in the knee through several different case series. The foot and ankle literature, however, is sparse, with only a few documented case reports or case series. At our institution, we have identified several patients with complications after this specific procedure. As a result, we report our case series of patients who developed talar avascular necrosis (AVN) after undergoing SCP.

METHODS

A retrospective review was performed of patients who underwent SCP for a talar BML at our facility or who were referred to our facility after undergoing SCP at an outside institution. Patients were included if they developed radiographic evidence of talar AVN after the procedure. Patient demographics, comorbidities, concomitant intraoperative procedures, complications, and subsequent interventions were reviewed.

RESULTS

Seven patients were identified as having radiographic evidence of talar AVN after SCP. Average time interval was 23 months postoperative from index procedure to radiographic confirmation of AVN. Two of the index procedures were performed at our institution, whereas 5 of the index procedures were performed at outside institutions and referred for further management. Three patients had documented risk factors for AVN before the SCP procedure. All 7 patients were symptomatic from the AVN.

CONCLUSION

We identified 7 patients who went on to develop talar AVN after having undergone SCP.

LEVEL OF EVIDENCE

Level IV, case series.

Osteochondral Lesions of the Talus: An Individualized Treatment Paradigm from the Amsterdam Perspective

Osteochondral lesions of the talus (OLTs) are characterized by damage to the articular cartilage of the talus and its underlying subchondral bone. Up to 75% of OLTs are caused by trauma, such as an ankle sprain or fracture. Physical examination and imaging are crucial for diagnosis and characterization of an OLT. No superior treatment for OLTs exists. It is paramount that an evidence-based personalized treatment approach is applied to patients with OLTs because lesion and patient characteristics guide treatment. This current concepts review covers clinical and preclinical evidence on OLT etiology, presentation, diagnosis, and treatment, all based on the Amsterdam perspective.

Osteochondral Lesions of the Talar Dome

Osteochondral lesion of the talar dome (OCLT) can be a devastating injury that affects mobility. Etiology of these lesions is debated but trauma seems the most supported etiology. Diagnosis of lesions is based on imaging. Conservative management, including weight-bearing restrictions, physical therapy, and supportive measures, often is first-line treatment. Nonsurgical modalities have mixed results and surgical measures often are necessitated for symptom relief. Surgical treatments vary in invasiveness and often are dictated by OCLT size. Studies show patient satisfaction increases substantially after having these procedures performed after failing nonsurgical measures. Results are encouraging, although thorough work-up and discussion should be undertaken.