Chapter 77

P1: OSO/OVY P2: OSO/OVY QC: OSO/OVY T1: OSO GRBT108-77 Thorne-2245G Thorne-v6.cls October 26, 2006 21:2 CHAPTER 77 ■ PRINCIPLES OF UPPER LIMB SURGERY BENJAMIN CHANG PREOPERATIVE PRINCIPLES History In no area of medicine is obtaining an accurate history be- fore initiating treatment more important than in upper limb surgery. The patient’s age, hand dominance, occupation, and history of prior upper-extremity problems are obtained. The date, time, mechanism, and circumstances (e.g., work related, contaminated) of injury are elicited. Information about the po- sition of the limb during the injury (e.g., fall on outstretched hand, hand open or grasping) and prior treatments may also be useful. For chronic or nontraumatic problems, it is essential to list details of the onset and course, and to prioritize the pa- tient’s complaints in the order of importance to the patient. A clear, prioritized list of complaints facilitates the physician’s or- derly follow-up on each problem at every visit so that progress or lack of progress can be systematically documented. Once the chief complaints are delineated, their effect on the patient’s functional ability in his or her occupation and activities of daily living can be evaluated. Pertinent past medical history, including anesthetic expe- riences, bleeding disorders, prior operations, current med- ications, allergies, and tetanus immunization status, are recorded. Physical Examination Together with a thorough history, the physical examination is the only diagnostic test needed in the vast majority of problems seen by the hand surgeon. A precise knowledge of the anatomy of the upper limb and its variations are essential for accurate diagnosis. The entire upper limb should be exposed and exam- ined systematically: circulation, sensibility, soft tissues, bones, joints, and active muscle functions.∗ Of course, the examina- tion should be tailored to each patient’s problem as guided by symptoms and history; not every test needs to be performed on every patient. Circulation can be evaluated by observing the color of the skin and nail beds, checking the temperature of the skin and the timing of capillary refill after blanching the skin with light pres- sure. Findings are interpreted by comparing them with those of normal parts. Arterial insufficiency produces a pale, cool limb with prolonged capillary refill and loss of tissue turgor. Venous insufficiency will result in a purple, congested extrem- ∗For a complete description of the physical examination, the reader is referred to an excellent handbook, The Hand: Examination and Diagnosis, published by the American Society for Surgery of the Hand, 3025 South Parker Road, Suite 65, Aurora, CO, 80232. ity with faster-than-normal capillary refill. These clinical pa- rameters can be combined with pulse oximetry and Doppler examination if needed, but conclusions must be based on the composite of findings, as no single test is infallible. Testing for viability with needle puncture is condemned. A digit with no arterial inflow for several hours can still “bleed” when pricked. This test serves only to provide avenues for infection. Brachial, radial, and ulnar pulses are palpated. Performing the Allen test (2) is useful to determine patency of both ulnar and radial arter- ies. The patient should raise and clench the fist to exsanguinate the hand while the physician compresses both radial and ulnar arteries at the wrist. As the patient opens the hand, the ex- aminer releases pressure on the radial artery and observes the capillary refill across the hand. The test is repeated, releasing pressure on the ulnar artery, and filling from the ulnar side is observed. Incomplete refill across the hand may occur in 10% to 15% of patients, and may indicate an incomplete superficial palmar arterial arch or occlusion of the radial or ulnar arteries. Sensibility is essential to hand function and is tested if there is any question of nerve damage from a direct injury, com- pression, or degenerative process. Denervated skin is dry and becomes smooth as it loses papillary skin ridges. Also, it does not wrinkle with immersion in water. These observations can be useful in examining children who are too young to cooper- ate and for identifying malingerers. The most useful screening test in the case of acute injury is to check light-touch percep- tion by comparing it with that of an uninjured part. Using a soft cotton-tipped applicator stick alleviates anxiety, especially in children. Static and moving two-point discrimination (2PD) measure innervation density and can be performed with a bent paperclip or blunt caliper to quantitate the level of sensibil- ity. Moving 2PD is a more sensitive indicator of the levels of sensibility needed for hand function. Abnormal measurements (>6 mm static and >3 mm moving 2PD at the fingertips) in- dicate axonal impairment (3). Two-point discrimination has the advantage of being somewhat quantitative, which allows for comparisons over time and between patients. Even more sensitive than 2PD is vibration sensibility (tuning fork) and pressure thresholds (Semmes-Weinstein monofilament testing). Although some variations and overlap exist in the sensory in- nervation of the upper limb, there are three autonomous areas on the hand, each of which is innervated by only one of three major nerves. The autonomous zone for the median nerve is the index fingertip, for the ulnar nerve it is the small finger’s tip, and for the radial nerve it is the dorsal side of the first web space. Soft-tissue coverage should be restored before reconstruc- tion of deeper structures is undertaken. Thick scars along the route of tendon transfers or across joints will limit mobility. During open wound examination, any skin deficits or devital- ized areas are noted and recorded on a sketch, but deep probing is not performed in the emergency room without appropriate anesthesia, lighting, and instruments. 741 Copyright © 2007 by Lippincott Williams & Wilkins, a Wolters Kluwer business. Grabb and Smith's Plastic Surgery, Sixth Edition by Charles H. Thorne. P1: OSO/OVY P2: OSO/OVY QC: OSO/OVY T1: OSO GRBT108-77 Thorne-2245G Thorne-v6.cls October 26, 2006 21:2 742 Part VIII: Hand Bone injuries are considered if gentle palpation reveals lo- calized skeletal tenderness. A fracture is suspected when sharp pain is accompanied by deformity, abnormal mobility, progres- sive swelling, and/or prominent ecchymosis. Radiographs of good quality and a minimum of posteroanterior (PA), lateral, and oblique views are essential. Specialized views may be re- quired to rule out fractures of a specific bone (e.g., scaphoid or hook of the hamate). A fracture should be described according to location, type, and deformity. The location is specified by the name of the bone and the portion involved (base, midshaft, neck, intra-articular, etc.). The type of fracture is described ac- cording to the pattern (transverse, oblique, spiral, comminuted, undisplaced) and whether a communicating skin wound (open or closed) is present. Describe the deformity according to the displacement (dorsal, volar, radial, ulnar) and angulation. By tradition, angulation is named for the direction of the apex and rotation for the distal segment in relation to the proximal one. Rotational malalignment in the fingers can best be ob- served by having the patient slowly bring all the fingers from a fully extended position into flexion. Any scissoring (cross- ing of fingers) usually indicates a rotational malalignment. For example: “The patient has a right fifth metacarpal neck frac- ture that is closed and comminuted with 3-mm volar displace- ment and 45 degrees of dorsal angulation, but no rotational malalignment.” Joints are examined for tenderness, active and passive range of motion, stability, and deformity. Abnormal physical findings necessitate radiographic examination. A “chip” fracture may indicate a ligamentous avulsion injury. Stress radiographs may be required in diagnosing ligamentous injuries, and should be performed after injecting local anesthetic to prevent pain and guarding. Muscle function depends on skeletal stability, functioning joints, and intact motor nerves and muscle–tendon units. Each unit for which there is reason to suspect injury should be tested, first without resistance to assess active range of motion, and then with resistance to assess strength. Pain or weakness against resistance suggests a partial tendon laceration. Dynamometers that measure grip and pinch forces are of little use with acute injuries, but are essential for evaluating and following chronic problems. The absolute numbers are less important than com- parison with those of the unaffected side. Some information may be gained by observing the resting posture of the hand. In the supine position, the resting hand should have the fingers in a partially flexed position, falling into a smooth cascade of progressively more flexion from the index to the small finger. A complete tendon laceration will cause the injured digit to fall out of line at rest. The tenodesis effect from passive wrist flex- ion/extension can also help evaluate suspected tendon injuries, even if the patient is under anesthesia. Wrist flexion increases tension on the digital extensor tendons causing passive digital extension. A digit with a transected extensor tendon will fail to extend when the wrist is passively flexed. This tenodesis ef- fect can also be used to test the flexor tendons, observing the digital cascade, as the wrist is hyperextended. However, a par- tially severed tendon cannot be diagnosed or excluded by any of these manipulations. Wound exploration is often the only means to establish the presence of partially severed tendons with certainty. Acute Injury The first priority is to rule out injuries to other parts of the body. To minimize patient discomfort, as much information as possible is obtained from observation rather than manipu- lation. Proceeding from distal to proximal, every structure in the zone of injury is systematically tested. The entire exami- nation need not be performed in the emergency room. There are two important questions to be answered in the emergency room. First, are any parts threatened by ischemia? Second, does this injury need to be treated in the operating room? If the an- swer to either question is yes, extensive exploration of wounds should be deferred to the operating room. Often, the basic in- formation is gained by examining the areas distal to the wound, including circulation, sensibility, and muscle/tendon integrity. The physical findings and appropriate radiographs guide exploration. It is helpful to triage injuries into three categories accord- ing to severity and urgency: (a) severe injuries that require im- mediate treatment; (b) severe injuries that require early treat- ment; and (c) less-severe injuries. Severe injuries that require immediate treatment include life-threatening situations and injuries that have resulted in ischemia and threaten survival of the parts. There are only two life-threatening upper limb problems: exsanguinating hemorrhage and necrotizing infec- tion (see Chap. 85). Hemorrhage in the absence of a coagu- lopathy can be controlled by elevation and direct pressure on the bleeding point. Makeshift tourniquets should not be used because they can apply dangerously high pressures, causing per- manent damage to underlying muscles and nerves. Clamping of “bleeders” in the emergency room is strongly discouraged because of the risk of injury to adjacent nerves. Tetanus prophylaxis should be considered for every patient with a wound. For clean wounds, tetanus toxoid should be administered if the patient has not been immunized within 10 years or has had fewer than the usual series of immunization doses. For highly contaminated or extensive wounds, tetanus toxoid usually should be administered, and if the patient has not been immunized within 5 years, tetanus immune globulin is recommended. Injuries that result in ischemia include amputations, vas- cular injuries, crush injuries, and electrical injuries. Muscle is the tissue most vulnerable to hypoxia and must be reper- fused within about 6 hours if it is to survive. Hypothermia is our only means of prolonging this time limit, as it lowers the metabolic rate of the tissues. Ischemic parts not amputated should be kept cool with ice, but taking care not to freeze them. One should suspect a compartment syndrome if the pa- tient complains of progressive pain disproportionate to the in- jury, if a muscle compartment feels tense on palpation, and especially if passive muscle stretching dramatically increases pain. High-pressure injection injuries can cause progressive tissue damage. These injuries vary in severity depending on the tox- icity and volume of the injected agent. The history is the key to diagnosis, as the toxic agent may be forced through a tiny, innocuous-appearing wound. Often, injection is at a fingertip with dissection of the material along the tendon sheaths all the way into the forearm. Left untreated, there will be progressive inflammation and destruction of the surrounding tissues and often this is inevitable despite early recognition and immediate operative debridement. Severe injuries that require early surgical repair include those of flexor tendons, open fractures, and joint injuries. If the skin wound is not extensive, it can be irrigated and closed in the emergency room, except for human bites, with delayed primary repair performed within a week. Extensor tendon and nerve injuries can be handled in a similar fashion except that definitive repair can be delayed for a longer period with the exception of independent units such as the extensor pollicis longus (EPL), which will contract and shorten rapidly. Se- vere injuries that require early treatment, not necessarily sur- gical, include frostbite, most chemical and thermal burns, and electrical injuries for which specific treatment is discussed in other chapters. The quality of the initial care for injuries is the most important single determinant of the final degree of recovery. Copyright © 2007 by Lippincott Williams & Wilkins, a Wolters Kluwer business. Grabb and Smith's Plastic Surgery, Sixth Edition by Charles H. Thorne. P1: OSO/OVY P2: OSO/OVY QC: OSO/OVY T1: OSO GRBT108-77 Thorne-2245G Thorne-v6.cls October 26, 2006 21:2 Chapter 77: Principles of Upper Limb Surgery 743 TA B L E 7 7 . 1 RECONSTRUCTIVE PRIORITIES IN THE UPPER LIMB 1. Restore circulation 2. Obtain good soft-tissue coverage 3. Align and stabilize the skeleton 4. Restore nerve function 5. Mobilize joints 6. Restore tendon function Reconstructive Cases Planning of surgical reconstruction should begin with the initial treatment, even though the reconstruction may take operations over many months to complete. The first step is to identify all of the injured structures by history, physical examination, and operative exploration. Once the deficits are understood, they should be prioritized if there is no potential for full recovery. Often, mechanical design must be simplified to a lower order of function. It is generally better to have a few things work well than many that work poorly. The following order of recon- structive priorities serves as a general guide based on prereq- uisites; each step in the sequence depends on successful com- pletion of the preceding steps (Table 77.1). Restoring adequate circulation is the first priority. Inadequate perfusion will impair wound healing, predispose to infection, and result in a cold in- tolerance. The next priority is good soft-tissue coverage, which might require replacement with skin graft, local flap, or distant tissue transfer. Delayed primary closure is indicated for badly contaminated wounds. Without adequate circulation and soft- tissue coverage, repair of underlying structures is futile. Even if they heal, it will be with excessive scar and adhesions. The third priority is to align and stabilize the skeleton. Fractures and dislocations should be reduced and stabilized. The fourth priority is to restore nerve function by repair or nerve grafting. The fifth priority is to mobilize joints that may have become stiffened as a result of chronic edema, inflammation, and dis- use. Severely stiffened joints may require surgical release. The last priority is to restore tendon function by repair, grafting, tendon transfer, or tenolysis. It is important that passive range of motion of joints crossed by a tendon be maximized before that tendon is reconstructed. The priorities listed above should be incorporated into a master plan, not necessarily separate operations. Replantation is an example of combining all of the steps into one operation. Several staged operations may be needed if the postoperative regimen for one part of the operation is different from that of another part. For example, osteotomy for malunion should not be done at the same time as tenolysis because the first requires immobilization and the second necessitates prompt mobiliza- tion. Once the deficits are identified and prioritized, steps with compatible postoperative regimens are combined as far as fea- sible. Each stage should be deferred until the tissues are soft, edema is resolved, and the joints are supple. This approach of identifying and prioritizing deficits, then grouping them into staged operations, can also be applied to nontraumatic recon- structive problems. OPERATIVE PRINCIPLES Anesthesia Surgery on the upper limb can be performed with a variety of anesthetic techniques: general, regional, or local infiltra- tion. Use of local infiltration anesthesia is limited to small lesions or to supplement a regional nerve block. General anes- thesia is usually indicated for children, for uncooperative pa- tients, when multiple operative fields are required, and for long procedures. The upper limb lends itself well to regional block anesthet- ics, which can be combined with judicious sedation if required for anxiety. The chief disadvantages of regional blocks are the time interval for its full effectiveness, the risk of incomplete anesthesia, and the limited tourniquet time. For a detailed re- view of local anesthetic agents, see Chapter 11. The most com- monly employed regional anesthetic blocks are brachial plexus blocks, intravenous regional (Bier) blocks, median and ulnar wrist blocks, and digital blocks. Either interscalene or supraclavicular brachial plexus blocks can give deep and superb anesthesia of the entire upper limb and allow long tourniquet times but require great skill to ad- minister, are not always complete, and carry a significant risk of pneumothorax or other complication. Blocks of the median or ulnar nerves, or both, at the wrist are safe, easy to perform, hurt less than palmar or digital blocks, and are useful for both emer- gency and elective operations. Anesthetic injections should be adjacent to and not into the nerves. Intravenous regional anesthesia (Bier block) anesthetizes the whole arm distal to the tourniquet. Thus for some purposes, it fills the gap between brachial plexus blocks and wrist blocks. The Bier block is conceptually simple: exsanguinate the arm and fill the veins with a local anesthetic. The details of admin- istration can be found in all anesthesiology texts. The main ad- vantage of the Bier block is that it is easy to perform and reliable in giving a good anesthetic block. Its main disadvantages are tourniquet pain, which limits operative time; compromised vis- ibility for precision dissections as the anesthetic flows into the line of dissection with every cut; and loss of anesthesia imme- diately when the tourniquet is deflated. Its risks are essentially that of tourniquet failure, which could allow a toxic dose of the anesthetic to be sent as a bolus into the body. Thus, although simple, this te