Are cam (controlled ankle movement) boots an appropriate treatment option for adult patients with acute ankle and foot injuries, including those with underlying conditions such as diabetes or poor circulation?

CAM Boots for Ankle and Foot Injuries

CAM (controlled ankle movement) boots are appropriate and effective for most acute ankle and foot injuries in adults, offering superior outcomes to immobilization with casts while providing adequate ankle restriction and offloading. 1

Primary Recommendation for Acute Ankle Sprains

For acute ankle sprains, apply a lace-up or semi-rigid ankle brace (not a CAM boot) within the first 48 hours and continue for 4-6 weeks, combined with immediate weight-bearing as tolerated and supervised exercise therapy starting within 48-72 hours. 1 This approach is superior to immobilization and leads to faster return to sports (4.6 days sooner) and work (7.1 days sooner) compared to cast immobilization. 1

Key Evidence Supporting Functional Bracing Over CAM Boots for Sprains

• Lace-up or semi-rigid ankle supports are more effective than elastic bandages or tape for ankle sprains 1
• Prolonged immobilization with CAM boots or casts delays recovery without improving outcomes and should be avoided beyond initial pain control 1
• Functional treatment with bracing allows earlier return to activity while providing adequate support 1

When CAM Boots ARE Appropriate

Fractures and Severe Injuries

CAM boots are biomechanically effective for restricting ankle range of motion and offloading the foot during weight-bearing, making them appropriate for fractures and injuries requiring immobilization with continued ambulation. 2, 3

• High CAM boots provide ankle immobilization comparable to short leg casts during weight-bearing (3.4±1.4 degrees for cast vs. 4.8±2.0 degrees for high boot) 3
• Both CAM boots and casts significantly reduce peak plantar surface forces (154.5-172.6% body weight) compared to normal shoes (195.0% body weight) 3
• Low CAM boots immobilize the ankle during non-weight-bearing but allow more motion during weight-bearing (7.8±3.4 degrees), making them less suitable for fractures requiring strict immobilization 3

Diabetic Foot Conditions

For diabetic patients with plantar foot ulcers, removable knee-high walkers (CAM boots) can be considered when total contact casting is contraindicated or not tolerated, though adherence is a major concern. 4

• Patients with active ulcers wore removable walkers only 28% of the steps taken, significantly limiting effectiveness 4
• CAM boots are appropriate for heavily exudating plantar ulcers requiring frequent inspection, ulcers with mild peripheral arterial disease, or mild infection under control 4
• Knee-high devices are superior to ankle-high devices for offloading diabetic foot ulcers 4

Charcot Neuroarthropathy

For active Charcot neuroarthropathy in diabetic patients, non-removable knee-high devices (including CAM boots rendered non-removable with fiberglass wrapping) are recommended for immobilization. 4

• Below-ankle devices should not be used for active Charcot neuroarthropathy as they do not provide adequate immobilization 4
• Treatment should continue for 4-6 weeks after clinical signs resolve 4
• Partial weight-bearing with assistive devices (crutches, walkers) is suggested to reduce time to remission and prevent complications 4

Special Populations and Contraindications

Patients with Diabetes and Poor Circulation

• CAM boots can be used for diabetic foot ulcers with mild peripheral arterial disease when healing potential exists 4
• Severely infected or ischemic foot ulcers require resolution of infection/ischemia before offloading can be applied 4
• Patients with loss of protective sensation should not walk barefoot or in thin-soled slippers, making CAM boots a reasonable protective option 4

Pediatric Patients

For low-energy lateral ankle injuries in children, CAM boots provide improved outcomes with lower complications than short leg walking casts. 5

• CAM boot treatment resulted in improved range of motion at 4 weeks, higher satisfaction scores (5.26 vs. 4.25), and significantly lower complications (0.04 vs. 0.54 per patient) 5
• Only 0% of CAM boot patients had continued symptoms at 8 weeks compared to 15.4% in the cast group 5

Critical Pitfalls and Complications

Biomechanical Compensations

CAM boots cause compensatory kinematic and kinetic alterations at the knee and hip joints, which may explain secondary site pain commonly reported by patients. 2

• The leg length discrepancy created by CAM boots can cause balance problems, joint strain, and discomfort 6
• Adding a leg length-evening orthotic to the contralateral shoe improves patient-reported balance (2.0±1.5 vs. 3.2±1.8 difficulty score) 6

Syndesmotic Injuries

CAM boots may increase external rotation of the fibula during weight-bearing in syndesmotic injuries, potentially causing malreduction. 7

• With isolated anterior inferior tibiofibular ligament rupture, CAM boots increased fibular external rotation from 8.40° to 11.17° 7
• With combined ligament injuries, external rotation increased from 8.81° to 11.97° 7
• Special care should be taken during CAM boot fitting to avoid overinflation of cushions in syndesmotic injuries 7

Diabetic Foot Ulcer Complications

• Long-term CAM boot use can cause foot ulcers (sometimes resulting in amputation), skin lesions during removal, pain, muscle weakness and atrophy, and falls 4
• The acquired limb-length discrepancy can cause musculoskeletal knee or hip complaints 4
• Consider a shoe raise for the contralateral limb to minimize leg length discrepancy 4

Conditions Where CAM Boots Should NOT Be Used

Do not use CAM boots as primary treatment for acute ankle sprains—functional bracing with lace-up or semi-rigid supports is superior. 1 CAM boots provide excessive immobilization for sprains, delaying recovery and increasing risk of chronic problems including decreased range of motion, pain, and joint instability. 1