Hand deformities are frequently seen in patients with EB, especially in RDEB. All the anatomical structures in the hand can be involved. Some of the commonly seen deformities include adduction contracture of the hand; flexion contractures of the interphalangeal, metacarpophalangeal, and wrist joints; and pseudosyndactyly of the fingers [6]. Such deformities of the hand are associated with dermal fibrosis, atrophic finger, and nail loss. Pseudosyndactyly is thought to be caused by repetitive minor trauma to the hand which subsequently leads to ulceration, fibrinous adhesion, and scarring. The severity of the deformity worsens with age and by the age of 20, 98 % of the patients with RDEB are at risk of developing a mitten deformity of the hand [7].

Surgical treatment is indicated when the deformities interfere with the hand function. Diminished hand function has been associated with poor quality of life in a study of 71 patients with DEB [21]. The goal of surgery is to allow patients to grip and grasp by releasing the pseudosyndactyly [6]. As with any procedures involved in patients with EB, release of pseudosyndactyly also requires careful planning to minimize complications and to improve outcomes. Surgery is usually performed under general anesthesia in younger patients but can be performed under regional anesthesia with propofol infusion in adults. If a tourniquet is used during the surgery, the use of nonadherent padding such as petrolatum-coated gauze and cotton wool padding under the tourniquet can prevent unnecessary skin trauma. When surgery for the hand is performed, some surgeons would release all contractures and pseudosyndactyly. However, release of only the first web space alone can improve patient’s independency greatly as the movement of the thumb contributes to 50 % of the hand function [8] with considerably less trauma and shorter recovery time. When surgery for digit separation is performed, care is given to avoid injury to the neurovascular bundles. First web space is released by incising the base of the first metacarpal dorsally, to the thenar muscles volarly. In severe cases, the first dorsal interosseous, the adductor pollicis, and the overlying fascia may need to be released. Pseudosyndactyly between the fingers is addressed from the interdigital space distally, lined on each side of dermis, and entered with the tips of scissors. The digits can be usually separated apart down to the web spaces. However, it may not be possible if underlying tissue is markedly scarred secondary to multiple previous surgeries in which case sharp dissection with a scalpel is needed to expose the subcutaneous tissue. The flexion contractures can be released with multiple transverse incisions in the interphalangeal and metacarpophalangeal joint creases or with a cruciate incision. K-wires are used infrequently for stiff or subluxed interphalangeal joints, but most surgeons prefer not to use wires across the proximal interphalangeal joints as it may cause a number of surgical complications. Pin-tract infection, articular cartilage damage, and prolonged postoperative joint stiffness in extension are some of the potential complications of K-wires [6].

Following the surgical correction of pseudosyndactyly and other hand deformities, surgeons usually cover the soft tissue defects using cultured keratinocytes, split skin grafts, full-thickness skin grafts, or cellular allograft dermal matrix. No difference in outcome was observed for those using nonbiological dressing with or without a graft. In children with EB following pseudosyndactyly release, the cover of the lateral defects of the fingers may not be necessary as the defects usually re-epithelize within 3–4 weeks. On the other side, these defects in adults are grafted as uncovered defects appear to take a longer time to re-epithelize in adults. Most surgeons would graft the first web space and palmar defects using a full-thickness skin graft (FTSG) or split-thickness skin graft (SSG). Compared to SSG, FTSG delays recurrence of contractures but FTSG take can be poorer than that of SSG resulting in potential scar formation [6].

Postoperative pain control is often managed with patient-controlled analgesia (PCA) pump in adult patients. One to 2 weeks following the surgery, patients are returned to the theater for cleaning of the wounds and/or grafts. Such dressing change and wound cleaning is done under general or regional anesthesia and/or sedation. For patients who had K-wires inserted, the wires are removed at 2 weeks. Custom-made splints made from perforated thermoplastic can be used after the third week following the hand surgery to keep the fingers apart from each other [6, 9]. Patient education and compliance with physiotherapy is an essential part of maintaining or delaying recurrent deformity and pseudosyndactyly. Information regarding the use of appropriate bandages, dressings, well-fitted splints, and gloves can be helpful in avoiding hand trauma and recurrent pseudosyndactyly [6].

Compared to other complications of EB, genitourinary tract difficulties including ureteric and urethral strictures are not as common, but occur in all types of EB. The case of genitourinary tract involvement in EB was first described in 1973 by Kretkowski in a 3-year-old boy who presented with bilateral hydronephrosis secondary to extreme urethral meatal stenosis and ulceration of the glans penis [9]. According to the NEBR, frequency of genitourinary tract difficulties in EBS, JEB, DDEB, and RDEB is 16.6, 30.2, 19.5, and 31.1 %, respectively [10]. Among urinary tract complications, urethral meatal stenosis was the most common complication, occurring in 11.6 and 8.0 % of patients with JEB-H and RDEB-GS. A study done by Kajbafzadeh et al. in 2010 found that the mean age of first manifestation of urological complications was 2.3 years, ranging between 1 day and 7 years [11]. Furthermore, they have found that males are more frequently affected but females have greater mortality rate from urological complications. Recurrent genitourinary infections, reduced urinary flow, and pain on urination are common presentations of genitourinary tract stenosis and obstruction. If urethral meatal stenosis is left untreated, patients will develop bladder distension, hydroureter, and subsequent hydronephrosis resulting in chronic kidney failure [12]. Considering the distal urethra, spontaneous blistering within the urethral orifice and mechanical friction from diapers or underwear on the glans penis in the chronic phase is thought to be the cause of urethral meatal stenosis and obstruction [11].

Vigilant monitoring of genitourinary involvement in patients with EB is essential as early detection and management is associated with better outcome than otherwise. Although there is no general consensus or guidelines on monitoring and management, at least 6-monthly urinalysis, blood pressure, and blood tests for serum urea, electrolytes, and creatinine are recommended, especially for patients with high risk, including RDEB and JEB. Ultrasound of kidney, ureter, and bladder (US KUB) is considered to be the first-line investigation for genitourinary involvement. A screening US KUB is recommended after the diagnosis of EB is established. Subsequent serial US KUBs are necessary for monitoring of renal morphology [11].

Due to the rarity of EB and such complications, there are limited data on the effectiveness of surgical interventions. In general, instrumentation of the urinary tract should be avoided to prevent secondary urethral and ureteric trauma and strictures [11]. Moreover, surgical treatment for meatal stenosis itself can cause further trauma and can result in poor outcomes [13]. Nonstick silicone dressings over the meatus may help to alleviate distal stenosis [18]. If instrumentation is inevitable in cases of severe stenosis and strictures, small-sized instruments should be used [11]. Children with symptoms of irritation should be treated conservatively. For patients with signs and symptoms of meatal stenosis, meatotomy, clean intermittent catheterization, suprapubic catheterization, and/or topical steroids may be considered [12]. In regard to circumcision, there is no difference between circumcised and uncircumcised boys in the frequency of meatal stenosis and urinary retention [11]. However, the NEBR recommends circumcision in EB boys as it may decrease the risk of other urological complications [10]. Some centers recommend doing circumcision after a child is out of diapers.