One of the most common symptoms of chronic arterial vascular insufficiency is intermittent claudication.47 This vascular-related pain has been described as a deep aching, cramping, muscle fatigue, or tightness that develops during physical activity and dissipates with rest. Although most common in the posterior compartment (gastrocnemius and soleus) of the lower leg, claudication can occur in any muscle with compromised blood supply, including the muscles of the thigh and hip. Claudication is the result of accumulation of lactic acid as a byproduct of anaerobic metabolism during muscle contraction. Several strategies are used to classify severity of PAD and of intermittent claudication. In 1954, Fontaine first defined four stages of PAD on the basis of the presence and severity of clinical symptoms (Table 19-3).⁴⁸ In 2007, the Trans-Atlantic Inter-Societal Consensus Task Force published a classification system (TASC II) for intermittent claudication with recommendations for appropriate intervention (endovascular angioplasty with or without stent placement, versus open surgical endarterectomy or bypass graft) based on location, length, and severity of occlusion or stenosis obtained from imaging studies.⁴⁹ Severity of PAD can be quantified using treadmill testing at a constant 2 mph speed, beginning flat and continuing with 2% increase in grade every 2 minutes, noting time to onset of claudication and time to maximum claudication. Change in the total distance that an individual is able to walk (e.g., number of city blocks or actual measured distance) before onset of symptoms is an alternative means of tracking progression of arterial vascular impairment.⁵⁰ When an individual requires opiates to manage vascular pain while at rest, or if there are arterial ulcers with dry gangrene in the toes or foot, the individual is classified as having critical limb ischemia, and is at high risk of amputation if revascularization fails or cannot be undertaken.⁵¹

When there is an acute or sudden occlusion of an arterial vessel (such that collateral circulation has not had sufficient time to develop), a much different pattern of pain occurs. Instead of relief with rest, pain is constant and somewhat unrelenting; it may be accompanied by feelings of tingling, numbness, or coldness as peripheral nerves of the lower limb are affected by ischemia.34 Although a limb with chronic arterial insufficiency demonstrates dependent rubor, the skin of an acutely compromised limb may be quite pale or blanched distal to the site of occlusion (Figure 19-1). Acute occlusion is often an emergent situation, requiring pharmacological or surgical intervention to restore blood flow to the limb, and often necessitates long-term anticoagulation.

Assessment begins with visual inspection of the lower extremity and feet, concentrating on skin condition, presence or absence of hair, and nail condition.52 Open wounds, callus, ecchymosis, dry necrosis and other skin lesions, as well as areas of erythema (redness), mottling, and altered pigmentation, are documented on a body chart. Circular wounds that lie under or are surrounded by callus on the plantar or weight-bearing surfaces of the foot are most likely neuropathic ulcers (Figure 19-2, A). Dry, blackened, or moist gangrenous wounds in the nail beds and between toes are likely signs of vascular insufficiency (Figure 19-2, B). Although “healthy” traumatic wounds often display clear serosanguineous drainage, any thickened, yellowish, or foul-smelling discharge from a wound suggests soft tissue or bone infection.

Open wounds around ankles or a distal leg surrounded by areas of darkly pigmented skin are typically the result of chronic venous stasis. Progressive circumferential measurements are taken to document the presence of pitting or nonpitting edema resulting from venous or lymphatic insufficiency, localized infection, or as part of an underlying systemic disease of kidney, heart, or lung. Skin temperature is assessed subjectively (using the web space or back of the examiner’s hand) or objectively using a surface thermometer. Cold areas in particular may have compromised arterial flow, while areas of increased temperature (especially if accompanied by erythema and swelling) often indicate underlying infection.52

In the presence of diabetic and other polyneuropathies there is often atrophy or wasting of the intrinsic muscles of the foot with apparent claw or hammer toe deformity.⁵³ Protective sensation (as measured by perception of Semmes-Weinstein 5.07 filament), as well as touch, pressure, vibration, and position sense, are likely to be impaired or inconsistent.⁵⁴ Additionally, impairment of the autonomic system often causes dry, tight, shining, easily cracked skin, as well as altered dynamics of blood flowing to the bones of the foot, increasing risk of Charcot arthopathy.^55,56

The least invasive and simplest strategy used to assess adequacy of vascular supply to the distal limb is palpation of distal lower-extremity pulses at the dorsalis pedis and posterior tibial arteries, popliteal pulse at the knee, and femoral pulse at the groin. Strength of pulses at each site is noted as absent (0/4), weak (1/4), normal (2/4), full (3/4), or bounding (4/4).40 If all pulses are palpable, it is likely that there is adequate circulation to heal a neuropathic ulcer. Absent distal pedal pulses do not, however, confirm vascular insufficiency; it is estimated that pedal pulses are nonpalpable in up to 10% of the general population.⁵⁷

When pedal pulses are not palpable, further assessment might include positional tests of capillary and venous filling time, auscultation with Doppler ultrasound, calculation of an ABI, taking segmental blood pressure of the limb, transcutaneous oximetry (pulse oximetry), pulse-volume recordings, MRA, computed tomography (CT) angiography, or duplex scanning.⁵⁸ (Refer to Chapter 18 for a detailed description of noninvasive assessment strategies.) Table 19-4 lists reference ranges for noninvasive tests.

High-resolution B-mode imaging combined with color and power Doppler and real-time spectral analysis have made duplex scanning one of the most widely used methods of noninvasive evaluation of arterial disease.59 Duplex scanning can accurately assess the location and degree of arterial disease from the level of the aorta to the level of the ankle. It provides accurate, objective information that supplements the physical examination. A disadvantage of this modality is the prolonged time it takes to perform an accurate examination of the entire extremity. Screening for arterial disease is done by comparing the signals from the various sites along the peripheral arterial tree and measuring the velocities at points of narrowing and comparing them with velocities in non-narrowed areas of the arteries.⁶⁰ This velocity ratio correlates to a 50% diameter narrowing when the ratio value is greater than 2. When the velocity ratio is greater than 4, the corresponding arterial narrowing is greater than 75%. Peak velocities at sites of narrowing can also be used to estimate the degree of narrowing. The sensitivity and specificity of this test is on the order of 90% or greater.⁶¹ Although some surgeons may rely solely on duplex scanning for preoperative peripheral arterial bypass planning, many prefer to more directly outline arterial anatomy using other imaging options.

Two additional methods that successfully outline the specific arterial anatomy are MRA and CTA (Figure 19-3).^62–65 Magnetic resonance imaging (MRI) detects radiofrequency signals given off by protons within a powerful magnet; such proton movement within body structures creates a detectable echo that can be imaged. Use of a contrast agent, such as gadolinium injected through a peripheral vein, greatly enhances the information gained from the images. MRA studies with gadolinium contrast are highly specific and 100% sensitive for identification of arterial lesions that require intervention.⁶⁶ The visualization of the distal runoff arterial tree when there are multiple levels of occlusions is much better than that seen with conventional angiography; however, the spatial resolution of MRA images is less than that available through invasive digital subtraction arteriography (DSA). Calcium within the artery, which impacts operative planning, cannot be seen in MRA. Other disadvantages include the inability to use this magnet-driven modality in patients with pacemakers, defibrillators, and intracorporeal metallic fragments that might migrate.

The advent of the helical or spiral CT scanners enabled CT technology to be applied to the diagnosis of peripheral arterial abnormalities due to the markedly reduced time required for scanning.⁶⁷ With this technology, large areas of the body can be scanned in 20 or 30 seconds. An iodinated contrast agent is given through a peripheral vein. This avoids potential complications of a direct arterial injection but does not preclude the risk of inducing renal failure. Although less-concentrated contrast agents can be used for CTA, the volumes required are larger than those for conventional angiography. Both noncontrast images and postcontrast injection images are taken. One advantage of CTA over MRA is the excellent visualization of vessel wall calcium deposits with CTA. But if there is much calcium, these areas become indistinguishable from the areas opacified after contrast injection. CTA performed for evaluation of the arteries in the lower extremities is being increasingly used in clinical practice. However, its spatial resolution is less than that seen with DSA and small peripheral arteries are not as well visualized.

Conventional arteriography and DSA are classified as an invasive examination strategies because both involve local surgical placement of a catheter into the femoral artery in the groin (or alternatively, the axillary, radial, or subclavian arteries, or the aorta), followed by introduction of radiopaque dye into the arterial tree and exposure to radiation.68

DSA computer-assisted x-ray method used to visualize vascular structures without superimposed bone and soft tissue usually seen on radiography.⁶⁵ The computer subtracts initially recorded x-ray images from those taken following ion injection of contrast medium, to isolate arteries of the limb. Contrast material (dye) is injected into the arterial tree, often at the groin into the femoral artery to assess patency of distal vessels and evaluate collateralization. This carries some risk of cholesterol embolization from atherosclerotic plaques at the site of puncture if the artery is diseases at the injection site; in addition, many of the dyes used can be nephrotoxic.⁶² Despite these risks, DSA is considered the gold standard against which other less-invasive imaging methods are compared.

Because of the risks associated with invasive procedures, conventional arteriography is most typically used just prior to revascularization (bypass⁶⁹ or thrombolysis⁷⁰) or amputation surgery to determine specific location and severity of vessel occlusion as well as the extent of collateral circulation. It may also be used in place of MRA imaging for individuals with metal implants such as pacemakers and total joint prostheses. Because contrast material used in arteriography are nephrotoxic, this procedure is not appropriate for individuals with renal dysfunction; it is also contraindicated for persons with cholesterol emboli syndrome, or allergies to substances containing iodine.^71,72

An invasive angiography procedure can take 90 minutes or more, depending on what is being imaged and how many images are required.⁷³ During the procedure the area that is to be punctured is first numbed with a local anesthetic agent. If the person undergoing the procedure is particularly anxious, the physician can administer a sedative agent orally or parentally before or during the procedure. After the area is adequately anesthetized, an 18-gauge, 2.75-cm needle with a hollow, thin-walled outer cannula and a sharp, beveled, inner stylet is inserted into the artery. Once the artery has been punctured, the stylet is removed and replaced with a guidewire that is carefully threaded farther into the vessel; this wire then guides placement of the catheter that will deliver contrast medium. Catheters as small as 1-mm outer diameter may be used (3 French), but more commonly, 4 or 5 French catheters are used with outer diameters of 1.32 mm and 1.65 mm, respectively. Once 40 to 120 mL of contrast medium has been injected, the catheter is flushed with heparinized saline to reduce the risk of clot formation. Successive still or continuous video radiographs record the progression of the dye through the limb’s arterial tree (Figure 19-4). After the catheter is removed from the femoral artery, manual compression is held locally at the site for several minutes and the patients remain at bed rest for a minimum of 4 hours. To ensure healing of the puncture artery, physical activity (include rehabilitation interventions) is postponed until several hours to a day after the procedure.

Intraarterial infusion of thrombolytic agents is used to manage several situations: (a) acute thrombosis of the extremity, (b) following percutaneous angioplasty, (c) after surgical bypass procedure of an extremity, or (d) after acute thrombosis of a diseased native artery.74–76 The most commonly used thrombolytic agents are streptokinase, urokinase, and tissue plasminogen activator.⁷⁷ Streptokinase and urokinase are non–fibrin-specific agents that convert circulating plasminogen to plasmin, which subsequently breaks down fibrin, one of the main components of clot. Tissue plasminogen activator is a fibrin-selective agent that acts locally by activating plasminogen to form plasmin, which, in turn, breaks up the fibrin in the clot. These agents are typically administered directly at the site of the clot (or as close as possible to it) via a catheter that is threaded through the arterial tree from the initial access site. Infusion may require several days; active rehabilitation begins after infusion is completed.

Intraarterial infusion of thrombolytic agents is typically followed by either systemic intravenous heparin therapy or oral warfarin therapy.^78,79 For individual’s status after bypass graft, long-term warfarin therapy is used to reduce risk of graft occlusion. The heparins are a class of agents that bind to antithrombin III to effect anticoagulation. Warfarin blocks the action of the vitamin K-dependent factors in the coagulation cascade. This has implications for the patient undergoing active rehabilitation because these agents increase the risk of bleeding complications, especially with manipulation of the wound in the immediate postoperative period of about 7 to 10 days.

In the postoperative period, should an individual on anticoagulant therapy report a sudden and significant increase in pain at the bypass site or in the residual limb following amputation, the likelihood of local bleeding must be quickly evaluated.⁸⁰ Outward signs of bleeding at the operative site, such as swelling, ecchymosis, hematoma, or active bleeding, may not be readily apparent should the bleeding occur at the subfascial level. Sudden onset of increased pain in the wound or extremity, along with recurrence of signs of limb ischemia, may also herald occlusion of the graft or progression of disease in the native vasculature following amputation at any level. It is important to identify signs of the failing graft as early as possible because the limb could possibly be salvaged if intraarterial thrombolytic therapy, as described earlier, is initiated soon enough.

Amputation is often the best option for some individuals with dysvascular or neuropathic disease when the arterial anatomy precludes bypass or if severity of disease is such that bypass cannot salvage irreversibly ischemic and gangrenous tissue, as well as persons with complex medical conditions at high risk for intraoperative and postoperative complications. Arterial bypass or thrombolytic therapy may be adjuncts to amputation so as to allow amputation at a more distal level, as long as there is no frank infection (wet gangrene) and the person’s arterial anatomy is conducive to bypass. In these cases amputation removes only nonviable portion of the limb, and the bypass or thrombolytic therapy improves the chance of healing at the more distal site.

Extensive gangrene of the foot, which is complicated by infection, is an indication for an open (guillotine) distal transtibial amputation. Time is given for the infection to be controlled by antibiotics and local wound care of the open surgical construct. The residual limb is then revised more proximally and a formal transtibial or transfemoral amputation with standard closure techniques is done.

Limb salvage and replantation are associated with high health care costs because of increased likelihood of multiple hospitalizations for successive surgical procedures, complications and delayed healing, and secondary amputation if the salvage attempt failed.88 With improving microsurgical techniques, long-term outcome (e.g., return to work, perceived health status) is fairly similar when primary amputation and successful limb salvage and reconstruction are compared; however, residual impairment, functional limitation, and disability can have a significant impact on the quality of life in both groups.^89,90 Any severe trauma to the lower extremities, whether salvage is attempted or amputation is the intervention of choice, is life altering.

In general, salvage attempts are most likely to demonstrate delayed healing or go on to secondary amputation if there has been high-energy injury, comminuted open fractures of Gustillo classification IIIC or higher, periosteal stripping, arterial injury with prolonged warm ischemia time, or complete disruption of the tibial nerve.⁹¹ Individuals or their family health proxy must be informed of the pros and cons of limb salvage versus amputation, including risk of infection and failure, as well as intensity and time frame for rehabilitation and likelihood of returning to premorbid functional levels.⁹²

If the decision is made to attempt limb salvage, the individual is taken from the emergency department to the operating room.⁹³ Arteriography (angiography) may be used to determine the extent of viable arterial perfusion. The next step is precise debridement of the damaged limb; surgeons must be sure that all compromised bone, muscle, and soft tissue are removed to reduce the likelihood of postoperative infection, necrosis, or later development of heterotopic ossification. It can be challenging to determine viability of cortical bone; cancellous bone is more likely to be revascularized. The biomechanical benefit of preserving as much bony length as possible must be weighed against the risk of developing osteomyelitis or delayed healing. Next, fractured fragments are stabilized with appropriate internal fixation, intramedullary rod, or external frame.

Defects in the bone may be filled with antibiotic-impregnated polymethylmethacrylate beads to further reduce the risk of infection and to preserve space for a later bone graft. The areas of the limb that were incised during surgery are stitched or stapled closed, while trauma-damaged areas may be temporarily closed with a biological dressing. The reconstructed limb is monitored closely, with sharp debridement of any nonviable tissue in the early postoperative period every 24 to 72 hours, as appropriate for the degree of wound contamination on initial injury, until a clean wound bed is obtained. Once the wound bed is consistently clean, the individual whose limb is being salvaged returns to the operating room (optimally within 1 week) for definitive closure of the surgical construct. This may be accomplished by delayed primary closure, split-thickness skin graft, local flaps, or, in some cases, vascularized pedicle graft. Subsequent to successful closure, the individual may return to the operating room for bone graft or transplantation or distraction osteogenesis to address osseous defects and limb-length discrepancy.

If limb injury is deemed too severe for salvage, a “guillotine” amputation may be performed to remove damaged tissues and restore hemostasis.83 If there has been significant contamination of the wound, the surgical construct may be left open (without skin closure) until the trauma team is satisfied that no infection has occurred.⁹⁴ Once the individual’s medical condition has stabilized and the wound is clean, revision to a definitive level of amputation can be performed. Amputation after severe injuries may require split-thickness skin graft or pedicle graft to achieve adequate skin closure. Skin pressure tolerance when wearing a prosthesis can be problematic later in the rehabilitation process when any type of grafting has been necessary.

Traumatic amputation is most likely to occur in young and midlife adults who are otherwise healthy. Once damaged tissue is removed and wound closure is achieved, circulation is often adequate for successful healing. These individuals, however, may be more likely to develop depression in the postoperative period because the injury was so sudden, and amputation so unexpected.⁹⁵ The sense of loss and alteration of body image after traumatic amputation can be more substantial than for an older adult with a diseased limb who “elected” to undergo amputation. Similarly, depression is a significant risk in those who are in the midst of limb salvage because of the likelihood of a long period of limited activity and altered appearance of the salvaged limb.

Until the 1990s most tumors of bone were managed by amputation with adjunctive chemotherapy or radiation.96 Currently, localized radical resection with allograph of bone, endoprosthesis, joint replacement or rotationplasty, along with and a combination of multiagent chemotherapy, isolated limb perfusion with tumor-necrosis factors, and radiation may be used.^105–109 These strategies have significantly reduced the number of tumor-related amputations performed each year. Amputation may be necessary when there is large, multifocal, high-grade, proximally positioned sarcoma, especially if there has been pathological fracture or significant involvement of neurovascular structures and if the tumor is chemoresistant.^110–114 Amputation is also performed when there is local recurrence following previous limb salvage.¹¹⁴

Limb-sparing intervention is often staged, requiring multiple surgeries, given the comorbidities associated with concurrent chemotherapy.¹¹⁵ In addition, the immunosuppression caused by chemotherapy increases risk of postoperative infection of the endoprosthesis; if such infections cannot be controlled medically, amputation of the limb is likely.^113,116 Survival rates and rehabilitation outcomes are surprisingly similar for those with primary bone or soft-tissue sarcoma managed by amputation or by limb-sparing surgery and reconstruction, although quality of life may be compromised as compared with peers without sarcoma.^117–119

When a tumor of bone or soft tissue is suspected, initial assessment strategies may include a radiograph, bone scan, CT scan, or MRI.¹²⁰ In individuals with previous history of cancer who present with bone pain, a radiograph may reveal a “moth-eaten” area within bone, with unclear boundaries or edges (Figure 19-5), demonstrating areas of osteolysis and reactive osteoblastic activity. A whole-body bone scan may be used to determine if there are multiple metastatic sites. A CT scan may be used to assess three-dimensional structural integrity and mineral content of the bone.

An MRI determines the extent of tissue involvement in marrow, bone, and surrounding soft tissue that is especially useful in planning surgical intervention for primary malignant tumor of bone or soft tissue (Figure 19-6).¹²¹ Laboratory tests may include blood assays, including sedimentation rate, C-reactive protein levels, serum electrophoresis, alkaline and acid phosphate levels, blood calcium levels, blood sugar levels, and hemoglobin concentration.¹²² For those with primary neoplastic bone disease, biopsy is used to determine cell type and contributes to pathological staging of the tumor. Depending on the tumor location, the surgeon may use an open frozen section, cannulated drill, or fine-needle aspiration to obtain a biopsy sample. For those with previous cancers of the breast, lung, bone, or colon, biopsy may not be necessary.

Once a primary tumor of bone has been typed and staged, the appropriate intervention is initiated.123 Nonpainful localized benign tumors typically do not require surgical intervention and are followed serially to watch for tumor progression. Symptomatic benign tumors (i.e., those that are painful or interfere with function) are treated by excision with bone graft or cement to fill the resulting bony defect.¹²⁴ Localized malignant tumors are excised using limb-sparing and reconstructive strategies.¹⁰⁸ Those with osteosarcoma or Ewing sarcoma almost always have preoperative and postoperative chemotherapy to minimize the likelihood of recurrence, while those with chondrosarcoma may not require such intervention.^109,125

For successful limb-saving surgery, the surgeon must first completely remove the tumor, achieving wide, clean margins in the bone above and below the lesion. A tumor in the middle of long bone that does not include epiphyses is often excised en bloc and replaced with an allograft transplantation or expandable endoprosthesis.¹²⁶ A tumor that crosses the epiphysis or extends into the joint space is also excised en bloc, and a total joint replacement performed to restore function of the limb.¹²⁷ When the tumor is large, high grade, and invasive of other soft-tissue compartments of the limb, amputation may be the most appropriate strategy.^110–114

Following limb-sparing surgery or amputation, appropriate rehabilitation interventions may include exercise to improve strength, range of motion, and endurance; energy conservation strategies; protective weight bearing during gait training with an appropriate assistive device; prosthetic rehabilitation (for those with amputation); functional training for mobility and activities of daily living; pain management (especially for those with metastatic disease); and patient and family education.¹²⁸ The therapist’s understanding of the biomechanics and tissue manipulation undertaken in the reconstructive or amputation surgery is essential for appropriate exercise prescription and activity planning. Therapists must also be aware of the impact of chemotherapy and radiation treatments on healing soft tissue and bone; on peripheral sensation; and on physiological response to exercise and activity, as well as the individual’s overall health status, immune response, prognosis, and level of energy.^129,130 The most successful rehabilitation programs are individualized and adapt to any adverse effects of concurrent adjuvant oncological interventions.¹³¹ Individuals with recent diagnosis of bone cancer often find significant support in interacting with others who have previously rehabilitated from limb-sparing or amputation surgery.¹³²