Medically Reviewed by Dr. Jeffery Agnoli, DPM — Board-Certified Podiatrist, Balance Foot & Ankle Specialists, Michigan. Last updated April 2026.
Chronic ankle instability (CAI) — persistent feelings of ankle giving way, recurrent sprains, and performance limitation beyond 12 months after an initial ankle sprain — affects approximately 40% of athletes who sustain a lateral ankle sprain, representing one of the most common causes of prolonged athletic time loss in sports medicine. The distinction between mechanical instability (ligamentous laxity from ATFL and CFL disruption) and functional instability (proprioceptive deficit and neuromuscular dysfunction in the setting of ligaments that may have adequate tensile strength) has direct treatment implications.
Mechanical vs. Functional Instability
Mechanical instability: stress radiography demonstrating anterior talar drawer >10mm (or 3mm asymmetry from contralateral side) or talar tilt >9 degrees (or 3 degrees asymmetry) indicates objective ligamentous laxity — the ligament has insufficient tensile strength to restrain talar translation under stress. Functional instability: objective ligamentous testing is normal, but the athlete reports subjective instability, impaired balance on single-leg stance testing, and peroneal reaction time delay (measured with EMG — the peroneal muscles react too slowly to inversion perturbation to protect the ankle). Many athletes with CAI have both components. The presence of mechanical instability is associated with poorer outcomes from rehabilitation alone and higher success rates from surgical stabilization.
Non-Operative and Surgical Management
Non-operative: structured neuromuscular training program (peroneal strengthening, proprioceptive balance training progressing to sport-specific tasks) produces clinically meaningful improvement in 50–70% of athletes. Ankle bracing during sport reduces re-sprain risk but does not address the underlying proprioceptive deficit — bracing should supplement, not replace, rehabilitation. Surgical management: modified Broström repair with InternalBrace augmentation is the gold standard for mechanical CAI failing 6 months of structured rehabilitation — produces 90%+ athlete satisfaction and return to sport in 4–6 months. Dr. Biernacki at Balance Foot & Ankle evaluates chronic ankle instability with stress X-rays and balance assessment, and provides the full spectrum of treatment from rehabilitation to Broström repair. Call (810) 206-1402 at our Bloomfield Hills or Howell office.
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Our board-certified podiatrists treat this condition at two convenient locations. Same-day appointments often available.
When to See a Podiatrist
Many foot conditions can be managed conservatively at home, but some require professional evaluation. See a podiatrist promptly if you experience:
- Pain that persists for more than 2 weeks despite rest
- Swelling, redness, or warmth that isn’t improving
- Numbness, tingling, or burning in the feet
- A wound or sore that is not healing within 2 weeks
- Any foot concern if you have diabetes or poor circulation
- Nail changes that suggest fungal infection or other problems
At Balance Foot & Ankle, our three board-certified podiatrists — Dr. Tom Biernacki, Dr. Carl Jay, and Dr. Daria Gutkin — provide comprehensive foot and ankle care at our Howell and Bloomfield Township offices. Most insurance plans are accepted.
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Board-certified podiatrists Dr. Tom Biernacki, Dr. Carl Jay, and Dr. Daria Gutkin see patients daily at our Howell and Bloomfield Township, MI offices.
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Dr. Tom Biernacki, DPM is a double board-certified podiatrist and foot & ankle surgeon at Balance Foot & Ankle Specialists in Southeast Michigan. With over a decade of clinical experience, he specializes in heel pain, bunions, diabetic foot care, sports injuries, and minimally invasive surgery. Dr. Biernacki is a member of the APMA and ACFAS, and his patient education content on MichiganFootDoctors.com and YouTube has reached over one million views.