Nail Surgery Complications: A Review of the Literature Free

Background: Nail surgery complications have not been addressed thoroughly. Summary: This review aimed to provide a robust literature review of nail surgery complications by identifying relevant data using a search of PubMed. It examines various complications, including general complications such as bleeding and infection; specific nail complications such as nail dystrophy; and common complications associated with specific nail procedures. Key Messages: This literature reviews better familiarizes dermatologists who perform nail procedures with relevant complications.

There is a dearth of literature reviewing nail surgery complications. The goal is to increase awareness of complications related to nail procedures among dermatologists that perform nail procedures.

There is a dearth of literature reviewing nail surgery complications [1]. This literature review examines various complications, including general complications such as bleeding and infection; specific nail complications such as nail dystrophy, and common complications associated with specific nail procedures. We can improve our counseling by being more aware of complications associated with nail procedures.

A comprehensive review of the literature summarizing the current knowledge of nail surgery complications was performed using PubMed. Publications say nail surgery complications dating from 1987 to 2023 are included. Search words to generate nail surgery complications included “nail surgery outcomes” and “nail surgery complications.” Once general complications and complications specific to nail procedures were identified using the aforementioned method, a more detailed search using the complication and “nail surgery” derived further publications.

It is imperative to understand nail anatomy prior to reviewing nail surgery complications (Fig. 1). The nail plate comprises the hard exterior nail surface. It is anchored by the proximal and lateral nail folds. The nail folds, cuticle, and nail plate protect the underlying nail matrix and bed [2].

The nail matrix harbors melanocytes and keratinocytes. The most proximal aspect of the matrix lies beneath the proximal nail fold. The proximal matrix produces most of the nail plate, namely, the dorsal part, and thus, damage to the proximal matrix causes more deformity than damage to the distal matrix. The distal matrix produces the ventral nail plate; though not seen in all nails, the distal aspect, lunula, is most visible in the thumbnail [2].

The nail bed is the space beneath the nail plate between the matrix and hyponychium. An important feature of the nail bed is the onychodermal band, which traverses the distal nail bed. Material that penetrates beneath the hyponychium is blocked by the onychodermal band [2]. Terminal branches of the palmar digital arteries supply the nails and digital tips. Periungual innervation comes from paired digital nerves, palmar and plantar [2]. Specifically, the 1st and 5th fingers are innervated by the dorsal proper digital nerves, while the other fingers are innervated by the palmar proper digital nerves [2].

Pain is an important consideration as equally effective procedures can cause varying levels of postoperative pain. Several nail surgery studies include pain as an outcome (Table 1) [3‒8]. Possibly related to pain and other complications, postoperative work day loss has also been reported [9].

For surgical matricectomy compared to phenol-based chemical matricectomy, there is a higher intensity of pain and longer duration of pain in the surgical group [5]. Partial matricectomy with curettage was found to have a shorter duration of postoperative pain compared to partial matricectomy with electrocautery (2 days vs. 3 days, p < 0.05) [6]. Phenol-based matricectomies resulted in a longer duration of pain (9 days) compared to NaOH (4 days) and TCA-based matricectomies (1 day) (p = 0.0092) [4].

In a study focused on the treatment of digital mucous cysts, 9% had persistent pain and swelling after excision [1, 10]. Another study demonstrated that 14% of patients experienced joint tenderness after mucous cyst excision [1, 11]. Among those who had nail bed and nail matrix subungual glomus tumor excised, 3 of the 22 patients (14%) had persistent pain which resolved spontaneously within a mean of 7 months [12]. After wide surgical excision of squamous cell carcinoma of the nail unit with full-thickness grafting, 15% experienced postoperative pain [7].

A rare but important complication of nail surgery is complex regional pain syndrome [13, 14]. Complex regional pain syndrome is classified as a neurovascular disorder after trauma to an extremity. This pain syndrome should be suspected if a patient, who underwent nail surgery, presents with sudomotor or vasomotor changes with pain that is out of proportion to the procedure [13].

Bleeding is a complication of surgical nail procedures [3, 5]. Phenol-based matricectomy resulted in less bleeding compared to non-chemical matricectomies and sleeve methods [3]. Of note, bleeding was grouped with discharge, so it is unclear the exact number is due solely to bleeding. Phenol-based matricectomies resulted in a longer postoperative oozing (14 days) compared to NaOH (11 days) and TCA-based matricectomies (6 days) (p = 0.01) [4].

Nail biopsy can be associated with infection rates of up to 11% [15]. For surgical matricectomy compared to phenol-based chemical matricectomy, there is a higher risk of infection in the surgical group (OR = 7.2 95% CI: 2.4–21.0) [5].

There are a few common methods for treating fingertip injuries with variable infection rates. In 1 study with patients with fingertip injuries, splinting with the native nail was associated with half the infections compared to splinting with the silicone nail [16]. Higher infection rates (8% vs 0% p < 0.0001) were also observed among pediatric patients who had their nail replaced or foil placed in repair of fingernail injury, compared to pediatric patients who did not have their nail replaced and nail was discarded [17].

In one study, only 1 of 13 patients who underwent nail matrix subungual glomus tumor excision experienced mild wound dehiscence [12]. Outcomes may vary depending on whether the excision site is in the nail bed or matrix.

The incidence of epidermal inclusion cyst development after excision of nail unit followed by full-thickness graft ranges from 0 to 38% of patients. After wide local excision of squamous cell carcinoma of the nail unit followed by full-thickness grafting, 18% developed epidermal inclusion cysts [7]. Cysts may result from proximal and lateral matrix horn remnants [24, 25]. A surgeon, therefore, must thoroughly excise the nail matrix horn, while preserving delicate neighboring structures. It is important to attempt to reduce the risk of cyst development as these complications can require additional nail surgeries and cause further complications.

Although keloids on hands and feet are uncommon, they remain a rare but possible complication of nail surgery. Eight of 681 patients developed keloids after syndactyly excision and reconstruction [18].

Nail surgery can be traumatic, and thus, recurrence rates of specific nail procedures should be closely examined to minimize harm. In a study focused on excision of digital mucous cysts, 3% developed recurrence [1, 10]. After wide local excision of squamous cell carcinoma of the nail unit, recurrence was observed in 4% of patients. [7] There are widely reported recurrence rates for squamous cell carcinoma using Mohs micrographic surgery (0–25%) [19]. Of note, the authors mention that the wide range of cure rates may be related to the smaller study sizes [19].

Shave biopsy can be associated with high rates of recurrence. Richert et al. [20] demonstrated that of 23 patients that underwent tangential matrix excision/shave removal of pigment from the proximal nail fold, 16 had pigmentation recurrence 8–12 months post-surgery. Another study demonstrated that 13% of patients had recurrence after modified shave surgery combined with the longitudinal-strip nail window technique for longitudinal melanonychia [21].

Regardless of approach (including excision involving nail matrix or nail bed), recurrence was not observed with any surgical excision of subungual glomus tumors [12, 22]. The risk of recurrence can be minimized by complete removal of the subungual glomus tumor [22].

Scarring is the most common complication related to nail surgery [24]. Scarring most often occurs when the nail matrix has been involved in the procedure [24]. De Berker et al. [26] found that 22% of nail surgery patients developed scarring, nail splitting, ridging, or pterygiums as postoperative complications.

A comprehensive understanding of nail pathology is crucial for effective nail surgery and anticipating potential complications. The number of melanocytes is lower in the nail matrix compared to the skin epidermis, and furthermore, most proximal nail matrix melanocytes are dormant, while 50% of the distal nail matrix melanocytes are active and produce pigment and 50% of the distal nail matrix melanocytes are dormant. Longitudinal melanonychia may be the first sign of nail melanoma [27]. Given the lesion contributing to the nail plate pigmentation, in the case of melanoma, is located in the matrix, matrix biopsy should be performed. We have reviewed potential complications associated with nail matrix biopsies, which vary depending on the type and location of the biopsy performed (Fig. 2).

In one study, 6 patients underwent finger fascial flaps combined with thin split-thickness toenail bed grafts for the treatment of large nail bed defects with exposed distal phalanxes and 2 of the 6 patients had slight nail deformities due to germinal layer injury [23]. In another study, nail dystrophy occurred in 25% of patients who underwent modified shave surgery combined with the longitudinal-strip nail window technique for management of longitudinal melanonychia [21].

Nail biopsies can be associated with nail dystrophy. In one study, 29% of patients developed scarring, nail width reduction, and secondary dystrophy post-biopsy [15]. Nail width reduction occurred in 18 of 38 patients (47%) that underwent longitudinal nail biopsies [15]. Furthermore, midline nail unit biopsies are less recommended because they increase a patient’s risk of split nail deformity [1]. Longitudinal biopsy on the center of the nail may result in chronic distal nail dystrophy or complete nail splitting. While lateral biopsy avoids these complications, de Berker and Baran report that excision of more than 3 mm of the lateral nail unit can lead to acquired nail malalignment [28]. Thus, each approach carries its own set of potential risks and benefits.

Shave removal/tangential matrix excision is associated with nail dystrophy. In Richert al. [20]’s study, 8 of 23 patients with longitudinal melanonychia developed dystrophy following removal of pigment from the nail matrix by shave removal/tangential matrix excision. In a study with patients with fingertip injuries, splinting with the native nail was associated with fewer deformities compared to splinting with the silicone nail (p < 0.015) [16]. Another study demonstrated that 4 of the 13 patients who underwent nail matrix subungual glomus tumor excision developed persistent nail deformity [12]. Partial distal splitting of the nail was a common complication reported after transungual subungual glomus tumor excision (19%) [22]. Splitting may be due to the formation of a scar between the proximal nail fold and nail matrix or result from scar formation within the matrix [1].

Though not a serious complication, distorted sensation can be a nuisance to patients and has been reported as a complication after excision of different tumors [7, 12, 14]. One of 13 patients who underwent nail matrix subungual glomus tumor excision reported decreased sensation that persisted 9 months [12].

Spicules may result from proximal and lateral matrix horn remnants [24]. If the entire nail matrix is not excised when performing a lateral longitudinal excision, spicule formation may result [24, 25]. The incidence of nail spicule regrowth ranges from 0 to 11% of patients; furthermore, the authors highlighted a slightly higher rate of nail spicule regrowth (14%) after wide surgical excision of squamous cell carcinoma of the nail unit followed by full-thickness grafting [7].

Nail plate avulsion, a surgical treatment required for late stage retronychia, can result in postoperative pain. Postoperative pain requiring analgesics was reported in a study with patients that underwent nail plate avulsion [29]. Other less common complications of nail avulsion include infection, hematoma, nail deformity, malalignment, nail impaction (distal embedding), local spicule growth, and swelling [30].

Topin-Ruiz et al. [7] demonstrated that early complications of wide surgical excision of the nail unit followed by full-thickness skin graft include graft infection, delayed wound healing, and pain. Late postoperative complications include hypersensitivity to mechanical shocks, mildly increased sensitivity to cold, loss of fine touch sensation, and epidermal inclusion cysts. In addition, the formation of digital myxoid cysts after en bloc excision for nail melanoma in situ has been reported [31].

Pain has been reported to be associated with slow Mohs surgery of nail apparatus melanoma in situ [32].

Surgical removal of a myxoid cyst has been associated with postoperative nail deformities [33]. In addition, excision of myxoid cysts is associated with bleeding, infection, and joint stiffness [31].

Excision is one of the most common treatment methods for subungual glomus tumors. One of the main complications of excision of glomus tumors is nail dystrophy [34]. The location of the glomus tumor may contribute to postoperative complications. One study showed that those with nail matrix involvement had complications such as nail deformity, decreased sensation, and prolonged pain sensation and those with nail bed lesions had prolonged pain sensation [12].

Pain was greater in those who underwent surgical matricectomy compared to chemical matricectomy [5]. In addition, infection rates were greater in those who underwent surgical matricectomy compared to chemical matricectomy [5].

When performing trephination for a subungual hematoma, the patient may have pain related to the pressure from the drilling or torquing motion [35]. Despite local anesthesia, patients may have this brief discomfort due to the pressure.

Most complications of nail surgery are related to damage to the nail matrix, especially in the proximal region [36]. Damage can result in nail deformity and scarring, leading to nail splitting [2]. Therefore, it is crucial that the surgeon accurately identifies the nail matrix and is deliberate to limit damage to the region. The surgeon must balance these considerations and the patient’s specific needs to determine a suitable treatment. A history of nail matrix damage can be associated with nail deformities [12]. Patient medical records should be queried for previous nail injuries, and realistic patient expectations for surgical outcomes should be set accordingly.

Awareness of medical conditions and medications that increase a patient’s risk of postoperative complications is also key. Nicotine use disorders, diabetes mellitus, and other vascular diseases can compromise blood flow to distal extremities, which then increases the risk of infection and delayed healing [1]. Immunocompromised patients face a greater risk of infection. Additionally, patients using anticoagulants have an increased risk of prolonged bleeding. By screening for these risk factors, surgeons may possibly be able to mitigate foreseeable complications.

It is especially important to sterilize the space beneath the hyponychium, a reservoir for microbes [2]. There is no evidence that postoperative use of antibiotics decreases infection rates [37]. One study found that patients who wore a gauze bandage developed significantly fewer infections than those who cleaned the surgical site postoperatively with alkaline or acidic soaps after partial nail ablation surgery [38].

In conclusion, while nail surgery complications are not common, it is important for the surgeon to be aware of these complications specific to the nail apparatus as well as complications associated with specific nail procedures. Although this literature review may be limited by the bias of article selection, it remains valuable since there is a dearth of literature that summarizes complications related to nail procedures for dermatologists performing nail procedures. Given these studies did not discuss the experience of the surgeon performing nail procedures, further research is needed to determine the association of complications with the technique and experience of the nail surgeon.

The authors have no conflicts of interest to declare.

This study was not supported by any sponsor or funder.

B.H.M. conceived and designed analysis. J.J.F. collected data (literature) and wrote the paper. B.H.M. and J.J.F. reviewed the paper.