Category: Dermatology

Onychomycosis, commonly known as fungal nail infection, affects up to 10-20% of adults, particularly in the feet, where toenails are more prone due to environmental exposure and trauma. Laser therapy has emerged as a promising alternative to traditional treatments, targeting fungi embedded in the nail plate via photothermolysis.

Understanding Onychomycosis

Onychomycosis primarily impacts toenails, caused by dermatophytes like Trichophyton rubrum, yeasts, or molds. In podiatry, distal lateral subungual onychomycosis (DLSO) is most common in feet, featuring nail discoloration, thickening, and crumbling, often leading to pain during walking or footwear use. Risk factors include diabetes, immunosuppression, athletic activities like golf, and occlusive footwear prevalent in Melbourne’s variable climate. Diagnosis requires mycological confirmation via KOH prep or culture, distinguishing it from psoriasis or trauma.

Conventional Treatments and Limitations

Oral antifungals like terbinafine achieve 70-85% mycological cure but risk hepatotoxicity and drug interactions, unsuitable for many podiatry patients with comorbidities. Topical agents penetrate poorly, yielding <20% cure rates, while mechanical debridement alone recurs frequently. These limitations drive demand for non-pharmacological options in foot care, where patient compliance is key for athletes or professionals.

Mechanism of Laser Therapy

Laser treatment employs selective photothermolysis, where specific wavelengths heat fungal elements to 40-60°C, disrupting cell walls without damaging surrounding tissue. Nd:YAG (1064 nm) targets melanin in fungal hyphae, penetrating deeply into the nail bed ideal for thick toenails. CO2 lasers (10,600 nm) ablate infected tissue via vaporization, enhancing drug permeation when combined. Low-level lasers like Lunula (635/405 nm) stimulate antifungal activity non-thermally, FDA-cleared for safety.

Types of Lasers Used

Common podiatry lasers include long-pulsed Nd:YAG (1064 nm), with 63-71% mycological cure; short-pulsed variants at 21%; and CO2 fractional/perforated at 45-95%. Lunula offers 80% success painlessly, treating all toenails in 30 minutes. Dual-wavelength Q-switched Nd:YAG (1064/532 nm) suits mild cases, improving clearance in non-dermatophyte infections. CO2 excels in severe DLSO but risks eschar formation

Clinical Efficacy Evidence

A 2019 meta-analysis of 35 studies (1723 patients, 4278 nails) reported 63% overall mycological cure for lasers, with CO2 at 74% outperforming others. Nd:YAG matches terbinafine efficacy (63%) but with fewer side effects, per 2024 reviews. Podiatry clinics report 70-90% improvement, superior to topicals, though full regrowth takes 6-12 months due to slow toenail growth (1 mm/month). Combination with topicals boosts rates to >80%.

Treatment Protocols in Podiatry

Podiatrists debride nails to <2 mm thickness first, enhancing penetration. Typical Nd:YAG protocol: 4-12 weekly sessions (e.g., 1064 nm, 4 J/cm², 30 ms pulse), 30 minutes total. Lunula: 4 bi-weekly exposures, no prep needed. CO2: 3-4 sessions at 3-week intervals, 30W for fractional ablation. Follow-up includes monthly cultures; maintenance for high-risk feet like diabetics. Australian TGA approves Lunula for onychomycosis.completepodiatry+5

Advantages and Safety Profile

Lasers offer pain-free (or mild warmth), no-downtime sessions, ideal for active podiatry patients. Safety is high; adverse events limited to transient pain (tolerable), rare bleeding, or erythema.<] Unlike orals, no systemic risks, suiting elderly or liver-compromised individuals common in foot clinics. Precision spares matrix, preserving biomechanics for gait.

Comparison to Other Modalities

Treatment	Mycological Cure Rate	Sessions/Duration	Side Effects	Cost (AU est.)	Podiatry Suitability
Oral Terbinafine pmc.ncbi.nlm.nih+1	75-85%	12 weeks daily	Hepatotoxicity (5%)	$100-200	Contraindicated in many
Topical (e.g., Amorolfine) southcarolinablues	10-40%	12 months weekly	Minimal	$50-100	Poor penetration
Nd:YAG Laser pmc.ncbi.nlm.nih+1	63-71%	4-12 weekly	Mild pain (<5%)	$500-1500/course	High; quick compliance
CO2 Laser pmc.ncbi.nlm.nih+1	74-95%	3-4 at 3 weeks	Bleeding (rare)	$800-2000	Ablative; severe cases
Lunula LLLT foothealthclinic+1	~80%	4 bi-weekly	None	$400-800	Painless; all nails

Lasers excel in efficacy/safety balance for foot onychomycosis.

Limitations and Future Directions

Recurrence (10-20%) persists without hygiene; severe matrix damage resists treatment. Evidence gaps include long-term RCTs (>1 year) and cost-effectiveness in podiatry. Ongoing trials explore combos like laser + tazarotene for enhanced clearance. In Australia, integration into CPD supports evidence-based use.

Laser treatment revolutionizes podiatric management of foot onychomycosis, balancing efficacy, safety, and convenience for diverse patients.

Pain around the side of a toenail is typically assumed to result from onychocryptosis (an ingrown toenail), where the nail plate pierces the periungual skin. However, lateral nail fold pain can exist in the absence of true nail plate penetration. Understanding the underlying non-ingrown causes requires an appreciation of the complex anatomy of the nail unit and surrounding soft tissues, as well as recognition of mechanical, dermatological, neurological, and systemic influences.

Nail Unit Anatomy and Biomechanical Considerations

The toenail apparatus includes the nail plate, nail bed, nail matrix, hyponychium, and lateral and proximal nail folds. The great toe bears significant load during gait, with lateral pressure increasing during propulsion and toe-off phases. Chronic, repetitive microtrauma or footwear-related compression can produce pain at the lateral nail fold even without nail embedding. This biomechanical component often underlies many “non-ingrown” nail pain syndromes.

For example, ill-fitting shoes that narrow at the toe box can press the nail edge against periungual tissue. Over time, this creates inflammation, mild edema, and tenderness along the nail sulcus, often mistaken for early onychocryptosis. Biomechanical factors such as hallux valgus, digital deformities, or pes planus can redistribute pressure so that the lateral margin of the hallux nail receives greater shear forces during walking.

Common Non-Ingrown Causes

Several distinct clinical entities can explain pain at the side of the toenail without ingrowth:

• Traumatic or repetitive pressure injury: Chronic shoe compression or athletic activity (e.g., running or kicking sports) may irritate the lateral sulcus, leading to focal tenderness and erythema. The nail edge remains intact, but adjacent soft tissue becomes inflamed.
• Nail plate impingement from curvature: Some nails exhibit excessive transverse curvature (pincer nails or involuted nails). Even though the plate does not penetrate the skin, the curving edge can compress periungual tissue and elicit pain from pressure alone.
• Periungual callus or corns: Hyperkeratosis can develop along the nail fold due to chronic friction, producing localized pain that mimics an ingrown nail. In some cases, a nail wall corn (heloma molle or heloma durum) forms in the lateral groove where skin folds consistently rub together.
• Paronychia (without ingrowth): Acute or chronic paronychia may occur secondary to bacterial or fungal infection in the nail fold. Chronic paronychia often presents with swelling, tenderness, and erythema of the nail border, typically linked to moisture exposure or irritant damage weakening the cuticle barrier.
• Onychophosis: The accumulation of hyperkeratotic debris between the nail plate and lateral fold can produce significant discomfort, erosions, and inflammation, particularly in elderly patients or those wearing constrictive shoes. The condition is common and often overlooked.
• Psoriasis or eczema involving the nail folds: Inflammatory dermatoses may affect periungual tissues, causing erythema, scaling, and pain. Nail psoriasis may coexist with subungual hyperkeratosis or pitting, leading patients to attribute discomfort mistakenly to a mechanical cause.
• Subungual exostosis or osteochondroma: A benign bony outgrowth beneath the distal nail bed can elevate part of the nail plate, altering local pressure distribution. This causes localized tenderness, especially along the lateral edge, sometimes before visible nail change occurs.
• Neuropathic pain: Localized nerve irritation, such as from trauma or peripheral neuropathy, may manifest as burning or shooting pain around the nail despite normal skin and nail appearance.
• Foreign body or micro-splinter: Tiny fragments (e.g., sock fibres or debris from pedicures) can lodge beneath the lateral sulcus, provoking inflammatory reactions without clear external entry sites.

Diagnostic Approach

Accurate diagnosis begins with careful clinical assessment and differentiation between mechanical, inflammatory, and structural causes. A thorough history and physical examination should note:

• Location and quality of pain (sharp, throbbing, or burning)
• Triggers (e.g., footwear, activity, water exposure, chemical irritants)
• Nail curvature and fold morphology
• Evidence of infection, drainage, or hypertrophic tissue
• Nail plate deformities, thickening, or color change
• Past trauma or history of systemic skin disease

Dermatoscopic or magnified inspection can help distinguish an embedded edge (true ingrown toenail) from non-penetrating variants. Probing gently beneath the nail margin determines whether the nail plate breaches the epithelium. Radiographs may be indicated when subungual exostosis is suspected, especially if chronic pain persists or nail elevation is visible.

In selected cases, microscopy or culture can confirm fungal or bacterial involvement, and a skin scrape or biopsy may help diagnose inflammatory or psoriatic nail disease.

Management Strategies

Management depends on the underlying cause. When ingrown toenail is excluded, conservative approaches generally focus on relieving pressure, reducing inflammation, and addressing contributing biomechanical or dermatological factors.

1. Footwear modification

Wider toe-box shoes are often the simplest and most effective intervention. They decrease lateral nail fold compression and prevent further microtrauma. Patients should avoid tight-fitting dress shoes or narrow sports footwear.

2. Nail care and debridement

Reducing nail plate thickness and curvature via professional podiatric care can relieve pressure. Careful removal of onychophosis or hyperkeratotic debris from the lateral groove often gives immediate pain relief. Emollients containing urea (10–25%) can soften keratotic build-up, while antiseptic or antifungal preparations may help manage chronic paronychia.

3. Padding and protective devices

Silicone toe sleeves, digital spacers, or custom padding can offload pressure from the affected fold. For individuals with structural deformities, orthoses or footwear adjustments targeting forefoot loading patterns may prevent recurrence.

4. Management of infection and inflammation

Topical antiseptics (e.g., povidone-iodine) or topical antibiotics can treat localized bacterial infection. Inflammatory dermatoses such as psoriasis or eczema respond to topical corticosteroids or calcineurin inhibitors applied to the periungual skin. Chronic paronychia benefits from reducing wet work exposure, applying barrier creams, and maintaining a dry environment.

5. Addressing structural causes

In cases of pincer or involuted nails, gradual flattening techniques such as orthonyxia (nail bracing) may relieve pain and guide normal growth. Surgical nail correction is reserved for severe or recurrent curvature not responsive to conservative measures. Subungual exostosis requires surgical excision once confirmed radiographically.

6. Neuropathic or idiopathic pain

If symptoms appear disproportionate to physical findings, neuropathic mechanisms should be considered. Gabapentin, topical lidocaine, or desensitization strategies may be appropriate in selected cases after ruling out local tissue pathology.

Clinical Vignettes

Consider a 38-year-old runner presenting with lateral border tenderness of the hallux nail, showing no embedding or drainage. The nail curvature is exaggerated, and compression testing elicits pain along the groove. Diagnosis: involuted nail causing pressure on the sulcus. Management with footwear modification, gentle edge thinning, and silicone sleeve resolved symptoms.

A second case involves a 64-year-old gardener with chronic swelling and tenderness along both hallux nail edges. Culture revealed Candida species. Chronic paronychia linked to moisture exposure—treated effectively with topical antifungal therapy and protective gloves during gardening.

Preventive Considerations

Preventing lateral nail fold pain relies on consistent nail and footwear care. Nails should be cut straight across with slightly rounded corners to avoid sharp spicules that can irritate periungual skin. Patients should be advised against aggressive digging or trimming down the sides of nails, as this often initiates inflammation that mimics early onychocryptosis. Regular monitoring is important for athletes, tradespeople, or individuals with deformities altering forefoot load, as they remain at higher risk for recurring periungual pain.

Pain at the side of a toenail does not always equal an ingrown nail. Instead, it encompasses a spectrum of conditions ranging from pressure-induced hyperkeratosis to inflammatory skin disease and neuropathic irritation. Careful assessment guided by nail morphology, surrounding tissue changes, and mechanical influences is essential for distinguishing these aetiologies. Podiatric management should aim to alleviate pressure, correct structural or footwear issues, and treat any infection or inflammation while educating patients on ongoing preventive care.

Understanding these non-ingrown causes of toenail pain broadens diagnostic accuracy and enhances care outcomes, reducing unnecessary procedures and ensuring symptoms are managed at their source.

Ingrown toenails are a common and painful condition in which the edge of a toenail grows into the surrounding skin, most often on the big toe. Effective treatment ranges from simple self‑care at home to minor surgical procedures in a clinic, depending on how severe the problem is and whether infection is present.

What is an ingrown toenail?

An ingrown toenail occurs when the nail plate curves and presses or pierces into the adjacent skin of the nail fold. This causes local inflammation, redness, swelling and tenderness, and can progress to infection with pus and overgrowth of tissue if not managed. People who trim nails too short or rounded, wear tight shoes, or have naturally curved/thick nails are particularly prone to the problem. Recurrent episodes are common if the underlying cause is not corrected.

Mild cases and home treatment

For early or mild ingrown toenails, conservative treatment at home is often sufficient. The aim is to reduce inflammation, relieve pressure from the nail edge, and guide the nail to grow straight out rather than into the skin. A typical first step is to soak the foot in warm water for 15 to 20 minutes several times a day, sometimes with Epsom salt or mild soap to soften the skin and nail and to help reduce discomfort. After soaking, gently drying the foot and using a clean cotton bud to nudge the swollen skin away from the nail edge can help free the nail margin.

Some people place a tiny wisp of cotton or dental floss under the very edge of the nail after soaking. This lifts the nail slightly away from the skin so it can grow over, rather than into, the nail fold. The material must be changed daily and kept clean to reduce the risk of infection. During this period, it is important to wear roomy footwear or open‑toed sandals so that there is no extra pressure on the affected toe. Simple pain relievers such as paracetamol or ibuprofen can be used if needed, provided there are no medical reasons to avoid them.

When medical care is needed

If pain is significant, the nail fold looks very red or swollen, there is pus, or home care fails over a few days, professional treatment is recommended. A doctor or podiatrist