Tips nail treatment
The open technique involves allowing the wound to heal by secondary intention with wound contraction, which pulls innervated pulp into the wound. This technique is applicable to distal and volar directed fingertip injuries without protruding bone. Some small fingertip wounds with a minimal amount of protruding bone can be treated with the open technique if this bone is debrided with a rongeur. The open technique is discouraged for wounds larger than 1 cm because healing time exceeds 3-4 weeks and significantly delays return to work. This approach is suitable for fingertip injuries in children because of their increased capacity to regenerate soft tissues. The complications potentially encountered with the open technique include loss of volume and pulp.
Primary Closure and Revision Amputation
Many fingertip injuries can be closed primarily or by recruiting adjacent soft tissues. Viability of the remaining soft tissues must be ascertained before application of a tourniquet. Occasionally, the fillet flap principle can be applied in reconstructing these wounds. Occasionally, bone shortening or revision amputation is required to allow tension-free primary closure of the soft tissues and adequate padding. Furthermore, in an effort to minimize recovery time and hasten return to work, some fingertip injuries are treated with revision amputation.
Complications of amputation procedures include the hook nail deformity, stump neuroma formation, and the quadriga effect. When the injury is located proximal to the lunula, the residual germinal matrix must be removed to prevent nail horn formation. Moreover, the hook nail deformity is prevented by trimming the distal nail bed 2 mm proximal to the bone. Removal of abnormal bone edges and preservation of the articular cartilage, which can minimize inflammation and provide a smooth contour to drape the wound edges over, can limit stump sensitivity.
A traction neurectomy can also minimize stump sensitivity. This severs the nerve while applying distal longitudinal traction, which results in 0.5-1 cm of proximal nerve retraction to prevent neuroma formation over the fingertip. Avoiding the approximation of the extensor and flexor tendons over the distal bone end minimizes the risk for quadriga effect. In general, revision amputations are frequently performed on manual laborers to allow for earlier return to work or on retired elderly patients for quicker wound closure and therapy, ultimately to minimize stiffness.
Skin graft application is considered for distally located and volarly directed fingertip wounds without exposed bone or tendon. Controversy exists as to whether split- or full-thickness grafts are better. Advocates for split grafts maintain the take is earlier and more reliable and wounds contract more, resulting in a smaller defect, while others favor full-thickness grafts for earlier re-innervation and more reliable, durable coverage. [, , , ]
In other words, split grafts may be preferable for wounds in which greater contraction is desirable. Full-thickness grafts can be obtained from the amputated tip by merely defatting the underside.
However, when the amputated part is crushed and macerated, this should not be used as a graft. Moreover, when the amputated tip is not available, a skin graft can be obtained from multiple areas. Glabrous skin provides a better aesthetic appearance and match of texture and color. Glabrous skin can be harvested from the hypothenar eminence or feet. Nonglabrous skin can be obtained from the wrist crease, forearm, medial upper arm, or groin.
Split-thickness skin can be harvested from the hypothenar eminence using a Weck blade after infiltrating with 1% lidocaine containing 1:100, 000 epinephrine. Full-thickness grafts are harvested in the configuration of an ellipse to allow for donor closure. The graft is secured circumferentially with 3-0 nylon sutures, which are left long to tie over an Adaptic gauze and a bolus of cotton, creating a bolster/stent. The finger is placed in a splint. This bolster dressing is removed at 5-7 days, and active range of motion is begun immediately.
Composite Tip Grafts
Reapplication of composite tip grafts, amputated parts containing bone fat or nail bed, can be considered for children younger than age 6 years. As composite tip grafts must initially survive by plasmatic imbibition until neovascularization, revascularization is not reliable for adults and tip grafts should not be reapplied for adults. The distal phalanx fracture is reduced and secured with internal fixation using a K-wire. The surrounding skin is approximated with absorbable chromic suture to avoid the hassle of suture removal in a child. Moreover, the child's upper extremity is placed in a soft splint using multiple Kerlix rolls from the hand to the upper arm. The splint is removed at 2 weeks.
Local Flap Options for the Fingers
When bone or tendon is exposed at the base of a fingertip wound, a local flap is required. The various local flaps used to reconstruct fingertips include volar V-Y, bilateral V-Y flaps, crossfinger flap, thenar flap, and island flaps. Flap choice depends on orientation and configuration of the wound, injured finger, and sex of the patient. Surgeons can optimize the reliability of these local flaps by avoiding tension on the suture line and preserving the traversing sub-dermal blood vessels into the flap.