Flashcards in Nail Surgery Deck (104):
The fingers and toes have paired sensory volar and dorsal digital nerves.
The dorsal nerves reach the distal phalanx of only the 2nd-4th digits.
F 1st and 5th only.
The distal nail bed attaches to the dorsal aspect of the processus unguicularis, a horshoe shaped rough bone excrescence at the tip of the distal phalanx.
The interosseous ligaments attach to the lateral spines of the processus unguicularis.
The germinative part of the nail unit is the cuticle and eponychium.
F Matrix and nail bed.
the distal or ventral matrix is the most proximal portion of the nail bed epithelium.
The nail bed extends from the matrix to the onychodermal band.
The nail plate is the product of the nail bed.
F Product of nail matrix.
Blood glucose levels are unimportant in diabetic patients undergoing toenail surgery.
F Need to be well controlled prior to toe surgery.
2-3mL of plain 2% lignocaine or prilocaine can be used per digit when performing a proximal digital block.
Splinting of the finger may be indicated after complex nail surgery
After nail surgery, it is not necessary to elevate the extremity.
F Should elevate for two days.
A transthecal block is performed from the dorsal crease of the MCP joint.
F Volar crease.
In a distal wing block, the injection points are distal to the DIP joint creases.
There is a general rule that the more superficial a nail change is, the more proximal the pathogenic process must be.
Nail clippings do not need to contain subungual hyperkeratosis.
F Should contain as much as possible.
Clippings performed for H&E give almost double the rate of positives compared to mycological culture.
A lateral longitudinal nail biopsy is appropriate for all diagnostic purposes, provided the nail pathology is in the lateral portion of the nail apparatus.
In a lateral longitudinal nail biopsy, a straight longitudinal incision starting at the distal crease of the DIP joint is carried to the tip about 2mm centrally from the lateral nail plate margin, and a second incision parallel to the first one along the lateral nail margin in the depth of the nail groove.
The lateral fold should be included in a longitudinal nail biopsy.
Matrix biopsies are the most important for most nail diseases.
A superficial matrix biopsy is unhelpful for diagnosing longitudinal melanonychia.
There will be no post-operative nail dystrophy after a superficial matrix biopsy, provided the biopsy is less than 1mm thick.
Biopsies of the proximal nail fold can be performed as a 2mm punch or as a narrow wedge with its base being at the free margin of the nail fold.
Distal nail avulsion is the classical method of nail avulsion.
During maneuvers in distal nail avulsion, the blunt tip of the elevator points away from the nail plate.
F Always points to the nail plate.
Distal nail avulsion is less traumatic than proximal nail avulsion.
Proximal nail avulsion is particularly useful when there is thick sunbungual hyperkeratosis.
Repeated nail avulsion causes thickening and overcurvature of the nail plate or nail dystrophy.
Matricectomy is the complete removal of the germinal matrix.
Nail ablation is definitive extirpation of the entire nail organ.
Matricectomy can be performed with surgery or adjunctive phenolisation, electroradiosurgery or carbon dioxide laser.
With total nail ablation, the incision is made just inferior to the hyponychium.
F Down to bone.
Large nail haematomas do not require any further investigation prior to treatment.
F x-rays are mandatory.
After trauma the nail plate is removed for appropriate examination of the mail bed and matrix, cleansed and stored under sterile conditions
Wet gauze only should be used to clean blood from the nail bed and matrix after nail trauma
F Sometimes 3% hydrogen peroxide is needed for cleaning
Approximately 20% of severe nail bed injuries have an accompanying fracture.
Common sequelae of trauma of trauma on onycholysis, split mail, ptertgium, various nail dystrophies, hook nail and malalignment
Foreign bodies under the nail plate are generally not painful
F Intense pain.
Tetanus prophylaxis should be considered if wooden splinters are lodged under the nail plate.
Periodical clipping of the gryphotic nail is often adequate to keep it under control.
T Can perform warm foot bath to soften nail, or use 40% urea, 50% KI ointment.
Gryphotic nails tend to be firmly attached to the nail bed.
F Loosely attached.
Phenolisation is ineffective for avulsing a gryphotic nail.
F Safest and easiest method.
Nail avulsion with phenol involves vigorously rubbing liquefied phenol into the matrix and sulci for 2-3 minutes once the nail plate is removed.
Pain after nail avulsion with phenol is typically severe.
Healing after nail avulsion with phenol takes 2-3 weeks.
T Should do daily foot baths while healing.
50% sodium hydroxide can be used as an alternative to phenol for nail avulsion of the gryphotic nail.
F 10% sodium hydroxide.
Nail spicules can occur if the lateral matrix horns are incompletely removed following surgical matricectomy.
The most successful treatment for pachyonychia congenita is vigorous curettage plus electrodessication of the matrix.
In pachyonychia congenita keratins 6a/16 and 6b/17 are present in the nail bed but not in the matrix
T 6a/16 – PC of Jadassohn-Lewandowsky
6b/17 – PC of Jackson-Lawler
Therefore a nail plate has normal structure but overlies a huge nail bed hyperkeratosis
In pachyonychia congenital the nail plate production has to be eliminated because the nail plate formed in a correct manner by the matrix cannon adhere to the pathological nail bed
Lateral longitudinal nail biopsies are used to narrow racket nails.
Ingrown toenails are most commonly seen in neonates, infants and the elderly. .
F Adolescents and young adults
Neonatal ingrown toenails should be treated aggressively.
F Conservatively. Daily massage with lubricant.
Neonatal ingrown toenails are due to a distal nail wall resulting from too short a nail plate.
Congenital hypertrophic lip of the hallux is characterised by a grossly hypertrophic medial nail fold
Congenital hypertrophic lip of the hallux tends to disappear spontaneously after several months.
Congenital malalignment of the great toenail refers to medial deviation of the long axis of the great toenail.
F Lateral deviation.
Ingrown toenails in adolescents occur due to a wide curved nail and a narrow nail bed.
In congenital malalignment of the great toenail, the malpositioned nail has no attachment with the nail bed.
In congenital malalignment of the great toenail if the nail reattaches it will take on a normal appearance and its axis will be normal
F Axis will remain oblique
Aside from its deviation, nails with congenital malalignment of the great toe nail otherwise appear normal.
F Grayish-green discolouration, oyster-shell like appearance.
Oncyholysis is most important for the prognosis of congenital malalignment of the great toenail.
Surgery is deemed necessary if there is no substantial improvement in congenital malalignment of the great toenail by the age of 2 years.
Repair of congenital malalignment of the great toenail involves performed a cresenteric rotation flap
Untreated nail malalignment inevitably will spontaneously resolve.
F Develops into early onychogryphosis.
The mechanisms responsible for formation of a juvenile ingrown nail all lead to a relative compression of the tip of the toe, so that the distal end of the nail has no more room and grows into the lateral nail folds.
There are three clinical stages of a juvenile ingrown toenail: 1. Erythema, oedema, pain on pressure 2. Infection and drainage 3. Granulation tissue and lateral nail wall hypertrophy.
For the adolescent-type ingrown nail, surgical avulsion of the nail alone has a cure rate of 70%.
F Recurrence rate of 70%.
Phenol cautery should not be used for treating adolescent-type ingrown nails due to its high recurrence rate.
F Has very low recurrence rate.
A distal wall is commonly the consequence of avulsion of the big toenail or when it was cut very short for too long a time.
Surgical treatment of a distal nail wall involves a fish mouth incision parallel to the distal groove around the tip of the toe.
Treatment for retronychia is generally conservative.
F Nail avulsion by proximal approach.
Pincer nails are characterised by transverse overcurvature increasing distally along the longitudinal axis of the nail.
The pain associated with a pincer nail is usually unbearable.
F Surprisingly mild.
Pincer nails can either have symmetrical or asymmetrical involvement.
Surgical treatment of a pincer nail is aimed at flattening it.
If acute paronychia does not improve after 2 days of treatment with antibiotics, surgical treatment is necessary.
T The nail matrix of children can be destroyed within 48 hrs of acute bacterial infection.
Acute paronychia involves removal of the distal one-third of the nail.
Chronic paronychia is usually painful
Chronic paronychia manifests with retraction of the perionychial tissue, detachement of the nail from the overlying thickened nail fold, and loss of the cuticle.
Viral warts are the most common reactive tumours of the nail apparatus
Cryotherapy of nail warts should be performed at 6 weekly intervals.
F Weekly or biweekly.
Excision of ungual fibrokeratomas should be carried out around its base down to the bone.
Subungual exostoses are commonly seen on the distal medial aspect of the terminal phalanx of the great toe.
T But may occur at any other digit.
Myxoid cysts generally occur in the absence of any bone pathology.
F Assoc with degenerative OA of the DIP joint.
There are no methods of determining whether a myxoid cyst is attached to the distal interphalangeal joint.
F Intra-articular injection of methylene blue will show connection.
Epidermoid carcinoma (IEC and SCC) is the most frequent malignant nail tumour.
F Second most frequent. Melanoma is most frequent.
Epidermoid carcinoma of the nail can present as longitudinal melanonychia.
Metastases are common from epidermoid carcinomas of the nail.
Carcinoma cauniculatum is a variant of verrucous carcinoma that rarely occurs under the nail. It should be excised with Mohs due to the high risk of metastasis.
F Almost never metastasizes, but everything else is true.
Unugual melanomas are always pigmented.
F 66-75% are pigmented.
Amputation of the digit in cases of ungual melanomas is associated with better survival rates.
F Conservatively operated pts have longer disease-free survival times.
The treatment of unugual melanomas should also include sentinel lymph node biopsy.
F No unanimous opinion on this.
The classical repair of a split nail is excision of the scar and meticulous repair.
Matrix grafting is the treatment of choice for wide nail splits and most cases of pterygium.
In nail surgery, tourniquets can be left on up to a maximum of 30 minutes.
F 20 minutes.
Pain after nail surgery is common and may sometimes be excruciating
Pain after nail surgery typically develops after 24-48hrs.
F This is suspicious for an infection.
Pain starting 10 days or longer after nail surgery is suspicious for reflex sympathetic dystrophy and requires intensive treatment to prevent it from becoming chronic.
Necrosis can occur after nail surgery if the sutures are too tight and not removed in time.
Stiffening of the distal interphalangeal joint after nail surgery is uncommon.
F Common – pts should hold finger in physiologic flexion.
The classical split nail repair is excision of the scar and meticulous repair. A narrow strip of nail is avulsed over the split, leaving the lateral portions attaches to the matrix and nail bed
T Great toe nail may be a superior donor site