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Bilateral arthritis of subtalar joint — Clinical Guidelines

Overview

Bilateral arthritis of the subtalar joint represents a significant source of chronic hindfoot pain and functional impairment, often resulting from posttraumatic conditions such as calcaneus fractures, degenerative arthritis, or other inflammatory arthropathies. This condition predominantly affects middle-aged to elderly individuals, particularly those with a history of trauma or chronic joint stress. Accurate diagnosis and timely intervention are crucial as untreated subtalar arthritis can lead to severe disability, gait abnormalities, and reduced quality of life. Effective management strategies are essential in day-to-day practice to restore mobility and alleviate pain, thereby improving patients' overall functional capacity and independence 1 2 3 4.

Pathophysiology

The pathophysiology of subtalar arthritis involves progressive degeneration of the articular cartilage within the subtalar joint, leading to synovial inflammation, osteophyte formation, and subchondral bone changes. In posttraumatic cases, such as those following calcaneus fractures, initial trauma disrupts the blood supply to the calcaneus, particularly affecting the posterior facet fragment. This avascular necrosis can result in sclerotic bone changes and compromised healing capacity, contributing significantly to joint instability and pain 1 2. Over time, repetitive microtrauma and chronic inflammation exacerbate cartilage erosion, leading to bone-on-bone contact and increased mechanical stress on surrounding structures. The resultant biomechanical alterations can further propagate joint damage and functional limitations 1 9.

Epidemiology

The incidence of subtalar arthritis is not extensively documented in large population studies, but it is recognized as a common complication following calcaneus fractures, with prevalence estimates ranging from 10% to 30% in affected individuals 1 5. The condition predominantly affects adults aged 40 to 70 years, with a slight male predominance observed in trauma-related cases. Geographic and occupational factors may influence risk, with higher incidences noted in populations engaged in high-impact activities or those with a history of repetitive lower extremity injuries. Trends suggest an increasing recognition and diagnosis due to improved imaging techniques and heightened awareness among clinicians 1 5.

Clinical Presentation

Patients with bilateral subtalar arthritis typically present with chronic hindfoot pain, often exacerbated by weight-bearing activities and relieved by rest. Common symptoms include swelling, stiffness, and a sensation of instability in the ankle and hindfoot region. Pain may radiate to the lower leg or foot, particularly in advanced stages. Red-flag features include significant gait abnormalities, such as a steppage gait, and signs of systemic inflammatory response if associated with rheumatoid arthritis. Patients may also report difficulty in performing daily activities and a noticeable decline in their ability to engage in sports or work-related tasks 1 3.

Diagnosis

The diagnostic approach for bilateral subtalar arthritis involves a comprehensive clinical evaluation complemented by imaging studies. Key diagnostic criteria include:

Clinical History and Examination: Detailed history of trauma, chronic pain patterns, and functional limitations. Physical examination focusing on hindfoot tenderness, range of motion limitations, and gait abnormalities.

Imaging Studies:

- X-rays: Essential for initial assessment, showing joint space narrowing, osteophyte formation, subchondral sclerosis, and possible malalignment. - CT/MRI: Provides more detailed visualization of bone and soft tissue changes, crucial for assessing avascular necrosis and cartilage damage.

Differential Diagnosis:

- Tarsal Coalition: Presents with similar symptoms but often shows bony bridges on imaging. - Ankle Arthritis: Pain localized more proximally around the ankle joint. - Neuropathic Pain: Presence of neurological deficits or symptoms not consistent with mechanical joint pathology.

(Evidence: Moderate) 1 3 5

Management

Conservative Management

Physical Therapy: Focus on strengthening the lower leg muscles, improving flexibility, and modalities to reduce pain (e.g., ultrasound, TENS).

Orthotics: Custom foot orthoses to offload pressure and correct biomechanical abnormalities.

Pain Management: Nonsteroidal anti-inflammatory drugs (NSAIDs) for symptomatic relief; consider corticosteroid injections for localized inflammation (maximum 2-3 per year to avoid side effects).

Surgical Intervention

Subtalar Arthrodesis: Indicated for refractory cases or significant joint instability.

- Technique: Open vs. Posterior Arthroscopic Subtalar Arthrodesis (PASTA). - Indications: Posttraumatic arthritis unresponsive to conservative treatment, severe joint instability. - Preoperative Considerations: Assess blood supply, bone quality, and alignment issues. - Postoperative Care: Early mobilization, weight-bearing as tolerated, regular radiographic follow-up to monitor union. - Complications: Nonunion, hardware-related issues, infection (monitor closely, consider prophylactic antibiotics).

Specific Surgical Factors for Success

Optimize Blood Supply: Ensure adequate vascularization around the arthrodesis site.

Bone Grafting: Use when necessary to promote fusion, particularly in avascular areas.

Technique Selection: PASTA may offer shorter recovery times and fewer complications compared to open techniques 2 3 4.

(Evidence: Moderate) 1 2 3 4

Complications

Nonunion: Risk factors include avascular bone, smoking, diabetes, prior ankle fusion, and revision surgery. Management involves surgical revision with bone grafting and stabilization techniques.

Hardware-Related Issues: Prominent hardware causing pain; revision surgery may be necessary.

Infection: Early signs include increased pain, swelling, and fever; requires prompt antibiotic therapy and surgical debridement if infected hardware is present.

Gait Abnormalities: Persistent instability or malalignment may necessitate additional corrective procedures.

(Evidence: Moderate) 1 2 5

Prognosis & Follow-up

The prognosis for bilateral subtalar arthritis varies based on the severity of joint damage and the effectiveness of treatment. Successful arthrodesis can lead to significant pain relief and functional improvement, with most patients achieving union within 6 to 12 months postoperatively. Key prognostic indicators include initial joint stability, patient compliance with rehabilitation, and absence of significant comorbidities. Regular follow-up intervals typically include:

3 Months: Radiographic assessment for early signs of union.

6 Months: Comprehensive evaluation of pain relief, functional status, and alignment.

Annually: Long-term monitoring for hardware-related issues and joint stability.

(Evidence: Moderate) 1 5

Special Populations

Elderly Patients: Higher risk of complications; careful preoperative assessment and tailored rehabilitation are crucial.

Pediatrics: Rare but can occur post-traumatic; management focuses on preserving growth potential and joint function.

Diabetic Patients: Increased risk of nonunion and infection; meticulous perioperative care and close monitoring are essential.

Post-Traumatic Cases: Special attention to avascular necrosis and bone quality; advanced imaging and surgical techniques may be required.

(Evidence: Moderate) 1 5

Key Recommendations

Consider Subtalar Arthrodesis for Refractory Cases: Indicated for patients with persistent pain and instability despite conservative management (Evidence: Moderate) 1 2 3 4.

Optimize Blood Supply During Arthrodesis: Ensure adequate vascularization to prevent nonunion (Evidence: Moderate) 1 2.

Use Posterior Arthroscopic Subtalar Arthrodesis (PASTA) When Feasible: Offers advantages in recovery and cosmesis (Evidence: Moderate) 2 3 4.

Regular Follow-Up with Radiographic Monitoring: Assess union status and alignment at 3, 6, and 12 months postoperatively (Evidence: Moderate) 1 5.

Manage Comorbidities: Control diabetes and smoking to reduce risks of nonunion and infection (Evidence: Moderate) 1 2.

Incorporate Physical Therapy Post-Surgery: Early mobilization and strengthening exercises are crucial for functional recovery (Evidence: Moderate) 1.

Monitor for Hardware-Related Complications: Regular clinical assessment to detect and manage pain from hardware (Evidence: Moderate) 5.

Consider Bone Grafting in Avascular Areas: Enhances fusion rates in compromised bone regions (Evidence: Moderate) 1 2.

Evaluate Gait Abnormalities Post-Treatment: Address persistent instability with additional corrective procedures if necessary (Evidence: Moderate) 1.

Tailor Management to Special Populations: Adjust surgical and rehabilitative strategies for elderly, diabetic, and pediatric patients (Evidence: Moderate) 1 5.

(Evidence: Moderate) 1 2 3 4 5

References

1 Kim HN, Choi YR, Kim BS, Kim YM, Lee J, Cho JH et al.. Factors influencing successful bone union of isolated subtalar arthrodesis for posttraumatic subtalar arthritis: a multicenter case series. Journal of orthopaedic surgery and research 2023. link 2 Rungprai C, Jaroenarpornwatana A, Chaiprom N, Phisitkul P, Sripanich Y. Outcomes and Complications of Open vs Posterior Arthroscopic Subtalar Arthrodesis: A Prospective Randomized Controlled Multicenter Study. Foot & ankle international 2021. link 3 Banerjee S, Gupta A, Elhence A, Choudhary R. Arthroscopic Subtalar Arthrodesis as a Treatment Strategy for Subtalar Arthritis: A Systematic Review. The Journal of foot and ankle surgery : official publication of the American College of Foot and Ankle Surgeons 2021. link 4 Rungprai C, Phisitkul P, Femino JE, Martin KD, Saltzman CL, Amendola A. Outcomes and Complications After Open Versus Posterior Arthroscopic Subtalar Arthrodesis in 121 Patients. The Journal of bone and joint surgery. American volume 2016. link 5 Albert A, Deleu PA, Leemrijse T, Maldague P, Devos Bevernage B. Posterior arthroscopic subtalar arthrodesis: ten cases at one-year follow-up. Orthopaedics & traumatology, surgery & research : OTSR 2011. link

Bilateral arthritis of subtalar joint