DIGITAL ARTERY LACERATION

Upper extremity arterial injuries account for up to 50% of all peripheral vascular injuries. Of these, brachial artery lacerations are the most common, followed by those of the ulnar and radial arteries, while digital artery lacerations are seen the least frequently. Digital artery lacerations usually occur secondary to open puncture wounds to the hand, but these injuries may also result from severely displaced fractures or crush injuries. Lacerations that transect the digital artery are obvious in most cases, but digital artery injuries associated with puncture and/or bullet wounds often require a higher level of suspicion to detect and accurately diagnose. A history of profuse bleeding, particularly pulsatile bleeding, associated with a finger laceration suggests a digital artery injury.  Each finger has two digital arteries and one intact digital artery will usually provide adequate profusion for the finger.  Thus, the necessity for repair of a single isolated digital artery laceration remains controversial.  When both digital arteries are cut then the finger will likely show signs of ischemia and repair of at least one digital artery is mandatory.^1-5

Options for a single isolated digital artery laceration include cauterization, ligation, repair or very rarely reconstruction with a vein graft.  However, single complete isolated digital artery lacerations often stop bleeding spontaneously or after the application of a simple pressure dressing and require no further treatment.^1-5

Pathophysiology

• A digital artery laceration occurs when the vessel is transected anywhere along its length. Possible sources of trauma include falls into glass, cuts secondary to a kitchen knife, industrial and traffic accidents, grinder/saw injuries, and stabbing, gunshot, and other penetrating wounds from violent altercations. Most lacerations involve penetrating or blunt trauma, but rarely iatrogenic causes and closed injuries may also be responsible.^3,5-8
  • Several studies have shown that glass is the material most commonly responsible for penetrating digital artery injuries.⁴
  • Although closed simultaneous digital artery injuries are rare, lacerations of both digital arteries can result in significant functional insult to the hand if left untreated, which is why hand surgeons must be suspicious when treating an injured digits.⁸
• A digital artery laceration can be a partial or a complete transection. Incomplete digital artery laceration can but rarely lead to pseudoaneurysms. Incomplete digital artery lacerations also have a tendency to not stopped bleeding spontaneously because the  digital artery ends cannot retract and thrombose normally.
• Digital artery injuries can also be categorized as noncritical or critical by the potential for ischemic tissue damage secondary to the unrepaired digital artery laceration. Patients with pre existing peripheral vascular disease may have digit perfusion jeopardized by a single digital artery laceration but usually both arteries must be cut before digit viability is in question.
• Isolated digital artery lacerations can occur in patients with inadequatel blood supply from the remaining digital artery.  Therefore, deciding whether an injury is noncritical is a clinical judgment that ideally will be made in the operating room after surgical assessment of the digital artery injury.  The dominance of the injured digital artery in the specific patient, associated injuries, and the medical comorbidities of the patient sould be considered.^1,3
• Critical digital artery injuries are associated with acute ischemia in the digit because of damaged and/or inadequate circulation in the remaining digital artery. With critical arterial injury the patient is at risk for amputation and hypovolemic shock.^1,3,9

Related Anatomy

• Related anatomical structures include:
  • Thumb radial, ulnar and dorsal digital arteries
  • Index finger radial and ulnar digital arteries
  • Long finger radial and ulnar digital arteries
  • Ring finger radial and ulnar digital arteries
  • Little finger radial and ulnar digital arteries
  • Brachial artery
  • Radial artery with its deep and superficial branches
  • Ulnar artery with its deep and superficial branches
  • Collateral arteries including the superficial palmar arch and the deep palmar arch
• In the proximal forearm, the brachial artery bifurcates at the radial tuberosity into the radial and ulnar arteries. The ulnar artery serves as the source vessel for the superficial palmar arch, while the radial artery serves as the source vessel for the deep palmar arch, and there are myriad anastomotic interconnections between these 2 systems.
  • The superficial palmar arch is a source of 3 or 4 common digital arteries, which in turn branch into the proper digital arteries to supply the fingers, while the deep palmar arch gives rise to 3-4 palmar metacarpal arteries. The dorsal arch, likewise, is the source vessel for the anatomically diverse dorsal metacarpal artery system. These 3 systems communicate at the level of the arches themselves, as well as along the pathway of the longitudinally oriented palmar and dorsal metacarpal arteries and common digital arteries.
  • Each finger has two proper digital arteries that run on either side along its length.  If one vessel is injured, one proper digital arteries usually maintain the blood supply to the entire finger.
  • The ulnar digital artery is dominant in the index finger, while the radial digital artery is dominant in the little finger. In the long and ring fingers, the ulnar and radial digital arteries are dominant respectively, but dominance is less obvious.^10,11
• Recent studies have shown that the vascular anatomy of the forearm and hand is very complex and true flow dominance can be difficult to assess accurately.¹¹
• Studies of the anatomic variability of the vascular network of the hand demonstrate that the superficial palmar arch is complete in more than 80% of patients, while the deep palmar arch is complete in more than 90% of patients.¹¹

Overall Incidence

• Almost half of the diagnosed vascular injuries occur in the upper extremity.
• The majority of the upper extremity vascular injuries will be to the brachial artery with fewer arterial injuries occurring in the radial, ulnar, and digital arteries.³
• Blunt injuries account for 6-10% of upper extremity vascular trauma and are often associated with musculoskeletal and neural injuries.³

Related Conditions

• Chronic vascular insufficiency
• Digital artery thrombosis
• Arterial aneurysm
• Arthritis
• Vasospastic disease

Differential Diagnosis

• Chronic vascular insufficiency
• Digital artery thrombosis
• Arterial aneurysm
• Arthritis
• Vasospastic disease

A typical patient is a 25-year-old right-handed male who was congregating with some of his friends around a bonfire at a popular location on local beach. Upon sitting down, the man placed his hands behind him and leaned back into the sand without inspecting the area. In this oversight, he failed to notice a broken bottle and plunged his left hand directly into it. The bottle sliced through the middle of his fingers and lacerated his ulnar proper digital artery and digital nerve of the index finger, causing immediate pain and rapid, pulsatile bleeding. One of his friends responded by applying pressure with a towel and took him to the emergency room.  The injury was diagnosed as a combined digital artery and nerve laceration of the index finger. The bleeding stopped.  The wound was irrigated, debrided and the skin sutured.  Later, the digital artery and nerve injuries were repaired at an ambulatory surgery center.

• Patients should consult a hand specialist immediately after determining the extent of the injury and treatment course to establish a hand therapy program, which will usually focus on the associated bone, tendon, and nerve injuries.¹⁰
• After an isolated digital artery laceration repair, early active protected finger range of motion (ROM) should be encouraged after 2-3 weeks. Application of a splint for 2-3 weeks may be needed for patients with concomitant tendon or bone injury to reduce swelling, provide stabilization and relative comfort, and allow early mobilization of uninvolved joints.^1,2,10

• Bleeding
• Infection
• Digital artery thrombosis after microsurgical repair
• Digital artery aneurysms or pseudoaneurysms (note both very rare)
• Cold intolerance and digital swelling
• Ischemia and tissue necrosis (myonecrosis)
• Amputation ((extremely rare)
• Paresthesia/decreased finger sensation with associated digital nerve injuries
• Impaired hand function1,2,4,11-14

• In noncritical digital artery lacerations, surgical ligation is considered a safe and effective intervention that often leads to excellent outcomes.
• Although surgical repair of digital artery lacerations was once associated with poor outcomes, modern microsurgical techniques are typically successful in producing favorable outcomes with high patency rates. While it’s not clear which technique is best, it’s generally recommended that primary digital artery repair should be attempted first if possible, while vein grafting should be recognized as a suitable alternative when it is not feasible and digital artery repair is critical to preventing digital ischemia.⁴
• Good surgical outcomes are generally correlated with the restoration of perfusion, regardless of whether bilateral or unilateral arterial repair is performed.¹⁵

• Current practice trend show increasing efforts to reestablish normal anatomy (ie, digital artery repair or reconstruction).^11,12
• Because of the proximity of the digital nerve and artery it is common to lacerate both structures simulataneously but rememberr the nerve is the more superficial structure in the finger.
• There is no conclusive data to support the concept that a digital artery repair facilitates nerve recovery after simultaneous neuropathy.²
• For noncritical digital artery lacerations, there does not appear to be a clear consensus regarding whether ligation alone or end-to-end repair is the best therapeutic option.^1,2,12
• Strong pulsatile “backflow” suggests the presence of adequate collateral circulation.^1,2
• Vasospasm can make adequate collateral circulation appear to be inadequate.^1,2
• Digital Allen testing can help define digital artery function.
• Digital artery lacerations can be properly managed without arteriography.^1,2
• Digital artery lacerations should be repaired without excessive tension at the repair site.^1,2
• Intraoperative and postoperative anticoagulation medications are indicated after digital artery laceration repairs.^1,2
• It is well established in the literature that nerve injury rather than arterial injury determines the long-term functional disability of the hand.¹⁰
• Although closed digital artery lacerations are rare and have an unexpected presentation, they still present a diagnostic challenge that should not be overlooked.¹⁵
• Doppler evaluation can help define digital artery function.
• Angiogram (arteriography)May be particularly helpful for patients with multiple sites of potential injury.³
• Laser Doppler Fluxometry
• Digital plethysmography [determines brachial artery index (DBI) where a numerical finding of greater than 0.7 indicates adequate perfusion] but this test is rarely available in emergency situations^1,7

New and Cited Articles

1. Koman LA, Smith BP, Smith TL, Ruch DS, Li Z. Vascular Disorders.  In: Wolfe SW, Hotchkiss RN, Pederson WC, Kozin SH. Green’s Operative Hand Surgery, 6^thedition, Philadelphia: Elsevier Churchill Livingstone, 2011, 2797-2240.
2. Gelberman, RH, Blasingame, JP, Fronek, A, et al. Forearm arterial injuries. J Hand Surg Am 1979;4(5):401-8. PMID: 501048
3. Hunt, CA and Kingsley, JR. Vascular injuries of the upper extremity. South Med J 2000;93(5):466-8. PMID: 10832942
4. Linnaus, ME, Langlais, CS, Kirkilas, M, et al. Outcomes of digital artery revascularization in pediatric trauma. J Pediatr Surg 2016;51(9):1543-7. PMID: 27156104
5. Faraj, AA and Craigen, MA. Closed digital artery injury. J Accid Emerg Med 1998;15(5):307. PMID: 9867398
6. Lee, CH, Cha, SM and Shin, HD. Injury patterns and the role of tendons in protecting neurovascular structures in wrist injuries. Injury2016;47(6):1264-9. PMID: 26971085
7. Johnson, M, Ford, M and Johansen, K. Radial or ulnar artery laceration. Repair or ligate? Arch Surg 1993;128(9):971-4. PMID: 8368933
8. Bougie, E and Cugno, S. Closed Digital Artery Injury in Children: A Case Report and Review of the Literature. Pediatr Emerg Care 2017. [Epub] PMID: 28953101
9. Ashbell, TS, Kleinert, HE and Kutz, JE. Vascular injuries about the elbow. Clin Orthop Relat Res 1967;50:107-27. PMID: 6029009
10. Thai, JN, Pacheco, JA, Margolis, DS, et al. Evidence-based Comprehensive Approach to Forearm Arterial Laceration. West J Emerg Med 2015;16(7):1127-34. PMID: 26759666
11. Higgins, JP and McClinton, MA. Vascular insufficiency of the upper extremity. J Hand Surg Am 2010;35(9):1545-53. PMID: 20807633
12. Rothkopf, DM, Chu, B, Gonzalez, F, et al. Radial and ulnar artery repairs: assessing patency rates with color Doppler ultrasonographic imaging. J Hand Surg Am 1993;18(4):626-8. PMID: 8349969
13. Ruch, DS, Aldridge, M, Holden, M, et al. Arterial reconstruction for radial artery occlusion. J Hand Surg Am 2000;25(2):282-90.PMID: 10722820
14. Aftabuddin, M, Islam, N, Jafar, MA, et al. Management of isolated radial or ulnar arteries at the forearm. J Trauma 1995;38(1):149-51.PMID: 7745646
15. Luczak, BP, Maher, R, Gurfinkel, R, et al. Closed digital artery injury. Ochsner J 2011;11(2):139-42. PMID: 21734853

Review

1. Bougie, E and Cugno, S. Closed Digital Artery Injury in Children: A Case Report and Review of the Literature. Pediatr Emerg Care 2017. [Epub] PMID: 28953101 

Classics

1. Gelberman, RH, Blasingame, JP, Fronek, A, et al. Forearm arterial injuries. J Hand Surg Am 1979;4(5):401-8. PMID: 501048
2. Cameron, JD. Cases of severe vascular injury to the hand. Hand1970;2(1):74-5. PMID: 5520129