Strategies in Compound Hand Injuries

Thomas Giesen, Olga Politikou, Maurizio Calcagni

Abstract

Compound fractures of the hand are one of the ultimate challenges for the surgeon and probably these contribute to define a hand surgeon. Complex open fractures with soft tissue destruction should be treated by someone with a solid knowledge about the diagnosis and treatment of all structures of the hand (and a great confidence in microsurgical reconstruction). These injuries need a precise strategy from the very beginning in order to achieve a reasonable good outcome, saving surgical time and useless procedures. It is in the interest of the patient, of the surgeon, and the community that a dedicated surgeon with all those competencies will deal with such devastating injuries. In this field, it is of paramount difficulty to provide evidence-based solutions and strategies. The authors offer their point of view about general strategies for the compound hand and some advices about how to deal with the different structures.

Keywords: compound injuries of the hand, open fracture, bone reconstruction, nerve tissue reconstruction, tendon repair, hand flaps, soft tissue reconstruction

9.1 Introduction

Decision making in compound hand injuries is one of the most complicated fields in hand surgery. The treatment of these complex injuries requires highly skilled hand surgeons, with great technical confidence in dealing with complex patterns of fractures, multiple soft tissue injuries and defects, reconstructive procedures, and high-level microsurgery. A complex compound injury to the hand should never be treated by different specialties in different surgical sessions; this would jeopardize a good functional result by delaying rehabilitation, while implying multiple operations for the patient, a longer hospitalization time, and higher costs for the community.1 Every injury is significantly different and a systematic classification is a paramount challenge. “Evidence-based” medicine is far from being available.

On top of this, social and cultural differences among different countries in the world, and also among different regions in the same country, as well as the social and cultural status of the patient, are elements heavily influencing the decision making.

Finally, yet important, it should be clear that a concomitant open fracture of a phalanx and a metacarpal with skin loss is not comparable with an open tibia fracture with skin loss; the principles of limbs traumatology do not apply necessarily to the hand, and in many cases are counterproductive.

9.2 Patient Expectation

We often take our hands for granted and only realize how functionally and aesthetically important they are when they are injured.

The goal of management of hand trauma is to restore anatomy and function while avoiding prolonged immobilization. No other part of our extremities is susceptible to stiffness as the hand; this fact is easily acknowledged when considering that the hand is the part of our skeleton that is most constantly moving.

Restoration of the aesthetic element is also a goal of the management.

In severe hand traumas, this task is even more difficult due to its anatomical and functional complexity. Reconstructive procedures have to address all damaged structures and tissues in order to achieve a good recovery.

Unfortunately, very often the expectation of patients is not realistic. In the compound hand, it should be made clear from the very beginning to the patient that a return to normality is a rare exception. The first contact with the patient should be done by an experienced hand surgeon who realistically can advise the patient about the expected outcome.

9.3 Clinical Examination

A complete medical history of the patient might be difficult to obtain in an emergency situation. Nevertheless, the mechanism of injury, the occupation of the patient, and potential pathologies that can jeopardize the result of a microsurgical procedure should be clarified before surgery.

In an ideal setup, the examination of the severely mangled hand should be performed by a most experienced hand surgeon in the operating theater. The main goal of the first examination is to assess the following:

The vitality of the soft tissue of the injured areas, including the perfusion of the digital extremities; the stability of the skeleton; the contamination of the injury; a primary balance of the structures that need to be reconstructed. As in traumatology in general, the most obvious lesion should be the latest to examine. Amputated parts, also from other extremities like the lower extremities, should never be discarded ( Fig. 9.1), as they may be used as tissue banks.

9.4 Imaging

Radiographs are the mandatory first-level examination. If available as an emergency examination, a computed tomography (CT) scan completes the radiographs for a better evaluation especially of the joints and adds valuable information about bone and joint status in concomitant closed injuries (e.g., adjacent fingers). Magnetic resonance imaging (MRI) is very rarely indicated, if ever. Angiograms might be indicated in injuries involving macrosegments.

Fig. 9.1 (a) Highly contaminated explosion trauma to the nondominant hand of a 52-year-old male patient. In the first surgical time, an aggressive debridement was performed and dorsal and palmar skin to the midcarpal hand temporarily readapted. (b, c) The only replantable middle finger was temporarily etherotopically replanted to the wrist on the ulnar artery. (d) In a second surgical time, when the extension of the necrosis to the palmar and dorsal skin became evident, a second debridement was performed, the palmar and dorsal skin of the hand restored with an ALT flow-through flap. (e, f, g) The previously replanted finger at the distal forearm was reamputated and replanted on the top of the fourth metacarpal through the vessels of the flow-through ALT flap. (h, i) The final functional result.

9.5 Classification

The fracture classification of Gustilo and Anderson,2 originally developed from experience with tibial fractures and frequently applied to long bones, has rarely been applied to injuries of the hand and current classification schemas for open fractures are insufficient to describe and indicate treatment of fractures of the hand. For example, the laceration size cutoffs for Gustilo–Anderson types (1 and 10 cm) are not realistic for a limb as small as the hand and its fingers.³ A specialized classification has been introduced³ that could take into account risk factors for infection specific to the hand when determining the best treatment of open fractures. This classification, summarized in Table 9.1, also introduced the concept that not all open fractures to the hand should be treated as emergency cases.

9.6 Timing

“Current guidelines suggest early surgical treatment of open fractures. This rule in open hand fractures is not well supported and may be practically difficult to observe.”4

The treatment of open fractures in the hand has not been well established. The above-mentioned study did not support the necessity of immediate operation (within 6–8 hours) on all compound lesion to the hands as the infection rate did not correlate to the timing of the definitive intervention.

However, the lesion should be immediately rinsed and antibiotic treatment started. Especially in compound lesion to the digits, a more complex reconstructive surgery can be delayed if we are able to adequately rinse the fracture, adapt the skin over the bone, and stabilize it with a splint or with an external fixator.

On the other hand, devascularizing injuries or instability of the skeleton, putting the survival of the segments at risk, must be treated without delay.

9.7 Surgery

In our practice, surgery of the compound hand is performed in several steps, but following few principles:

• Simplify: In a very complex injury, restoring a digit or hand with all its structures to perfect anatomy increases the complexity of the procedure and may be far too time and resource consuming and not going to improve the functional outcome. Focus on the important structures. A typical example is the priority that flexors have above the extensors. Or, the management of complex phalanx fractures with a small shortening of the bone resulting in an easy and more stable fixation and a more straightforward approximation of tendons, vessels, and nerves, avoiding the need of multiple grafts.

Another example is in case of multiple finger injuries. The thumb has always the highest priority. Then it is important to “ulnarize” the hand giving priority to the middle finger, for example, over the index finger, possibly using the index finger to reconstruct a better middle finger than spend time to reconstruct a bad index and a bad middle finger.

• Do everything in a single session: As largely reported in Europe 1 and United States,⁵ we tend to repair or reconstruct as much as we can in one session in order to start the mobilization of the hand as soon as possible. This principle is only apparently in contrast with the principle of simplification. In reality, it means that once a plan is made for the repair or reconstruction of the injured segments, most of the steps should be performed during primary surgery in order to permit early mobilization.

• Work systematically: When repairing or reconstructing, we prefer to do it structure by structure rather than segment by segment in case of multiple segment injuries.⁶ This has an important practical value; for example, finish the work needing an image intensifier before proceeding to the microscope, rather than alternating several times. Or, in the case of revascularization of multiple segments, avoid delaying revascularization of the last segment, when, for example, being happy with the reestablished vascularity of the first two segments.

9.8 Surgical Steps

9.8.1 Debridement

Debridement is the most difficult moment in the reconstructive process. Not because of the required technical skills, but because of the expertise required to make a judgement of the lesion, to decide whether tissues are viable or not, and to decide what shall be reconstructed and what shall not be reconstructed. The most experienced surgeon at hand with the highest confidence in the reconstructive possibilities should perform the debridement. As stated by Lister and Scheker, “… much discipline is necessary when debriding because the luxury of a second look is surrendered.”7

In simple words, debridement should be performed by someone who is not afraid of excising tissue of dubious viability, thanks to her or his solid experience. Tissue without potential viability must be excised in order to make a proper reconstruction and not preserved in the hope that it may possibly to survive.

9.8.2 Bone Fixation

Bone fixation is probably the field where the principles of orthopaedic traumatology that apply to the long bones strongly diverge from the principles for the reconstruction of the hand.

In compound lesions, and especially in devascularizing injuries, bone fixation needs to be quick. In multiple replantation or in severe trauma, the use of longitudinal K-wires or K-wires and intramedullary screws 8 saves time for the microsurgical procedures as in the example in Fig. 9.2. Intramedullary fixation with screws is preferred to plates as it is a quick way for fixation without applying fixation material on the outer surface of the bone, giving a better functional result.

Bone grafting, contrary to what is believed by many, can be performed in primary surgery after adequate debridement if viable soft tissue coverage can be provided immediately, using a local, distant, or free flap.^9,10

Likewise, in case of joint destruction, the use of silastic implants or spacers simplifies the procedure, providing mobile joints. There is no evidence whatsoever of an increased risk of infection.11 Also in this case, well-vascularized soft tissue coverage is mandatory as shown in Fig. 9.3.

9.8.3 Revascularization

If any terminal segment is devascularized, the next surgical step is to restore vascularity. If an additional venous drainage is needed, the first author of this chapter prefers to perform the vein anastomosis first. In case of vein defect, very rarely a graft is needed; a vein can be harvested in some cases from an adjacent finger or a dorsal V–Y flap or hatchet flap 12 can be harvested in order to reapproximate the vein ends. In injuries to the midcarpal hand, the wrist and the forearm, a proximal vein can be rerouted to fulfill the length requirements.

In avulsion injuries, even after significant bone shortening, a vein graft may be needed. Vein grafts can be harvested from the distal forearm for the fingers, including a skin pad as an antegrade free venous flap if there is skin shortage.¹³ In case of large skin defects to the midcarpal hand or more proximal part of the upper extremity, a flow through flap can carry the vessel for the segment to be revascularized ( Fig. 9.1).

9.8.4 Flexor Tendon Reconstruction

Flexor tendon repair should be the next step. In our study on simple flexor tendon injuries in zone 2,14 we refrained in some cases from repairing the flexor digitorum superficialis (FDS) tendon. In the case of compound fractures in zone 2, we usually do not repair the FDS tendon. This is also the case in lesions at the level of the carpal tunnel. The bulky repair of both the FDS and the flexor profundus (FDP) tendons together will unavoidably cause adhesion in the restricted space of the carpal tunnel. In our opinion, the technique of suture in itself is not as relevant as commonly believed. We prefer a six-strand core suture known as the M modification of the Tang technique,¹⁵ as it has been demonstrated that there is no need for a circumferential suture with this technique.¹⁶ Saving time by avoiding, for example, six or seven circumferential sutures may be crucial in extensively lacerated hands.

In the fingers, we do not reconstruct pulleys primarily, provided that there is no concomitant lesion of the A1 and the A2 pulleys, and there is no concomitant lesion of the A4 and A2 pulleys. In cases with concomitant lesion of the A1 and A2 pulleys or A2 and A4 pulleys, we usually use the resected FDS to reconstruct a diagonal pulley at the A2 level.