CHAPTER 34 LESIONS OF THE HEEL

Michael C. McGlamryt D.P.M.

Malignant and benign tumors of in the foot Imaging of the calcaneus can easily be have traditionally been characterized as rare, or at accomplished in the office with plain film least unusual. \7hen these lesions do appeat, radiographs. Views which may be helpful in however, they are frequently localized to the heel. evaluating lesions of the heel include the lateral, They may be discovered on a routine radiographic axial, medial, lateral oblique, and occasionally evaluation for an unrelated condition. Only careful sunrise and Broden's views. More extensive evaluation of good quality radiographs and a evaluation may be obtained with special studies correlation with a thorough history will lead to an such as bone scans, magnetic resonance imaging accurate diagnosis and appropriate treatment. (MRI), and computed tomography (CT). These A review of a variety of lesions which may be studies may aid in ful1y evaluating the volume, seen in and around the calcaneus will be density, and metabolic activity of the lesions. The presented. Additionally, the typical patient higher sensitivity of these modalities may assist in population for each pathologic process will be detecting pathology such as coltical breaks not outlined to help correlate the information gained apparent on plain films. Despite the value of these from the history and physical with radiographic studies, they should still be considered ancillary, and imaging study information. For the purpose of and should be ordered under the appropriate discussion, the lesions of the heel have been circumstances. divided into categories of benign and malignant Initial evaluation of any lesion on plain film tumors. Although this is somewhat artificial and not radiographs should be fully characterized in a completely technically correct, it does correlate systematic fashion. This description should include well with plain film radiographic findings. the site (although this article is primarily concerned Overall, the incidence of bone tumors in the with the calcaneus), size, density compared with foot accounts for only 70/o to 20/o of bone tumors in surrounding bone, margin characteristics, and the body. Of these lesions, the benign lesions out- effect on the natural cortical barrier of the bone. A number malignant lesions 4 to 1. The most system of description using five levels of evaluation common sites of occurrence are the calcaneus and has been described by Zulli, and has appeared on metatarsals. The great majority of the lesions several occasions in recent literature. discussed have been seen by the author in the last several years. Case presentations will attempt to BENIGN LESIONS show the "real life" nature of these problems. In addition to traditional neoplasms which Unicameral may be seen in the heel, other non-neoplastic Unicameral or solitary bone cysts are the most processes may include sequestered infection in the common bone lesion in the foot. They are found form Brodie's , sclerotic changes of a most frequently in the calcaneus C75o/o to 850/o of all and from previous stress, or acute fracture cases in the foot), but may also be seen in the talus enthesiopathies which may be biomechanical or and metatarsal. Unicameral bone cysts begin in metabolic in origin. children and teenagers, and generally do not The value of the history and physical enlarge once the patient has reached skeletal examination cannot be overemphasized in maturity. Often, these lesions are asymptomatic, evaluation of these lesions. Important information and may be discovered on radiographs for an which may be gained is the quality, duration, unrelated condition. If symptomatic, the possibility course, and onset of pain as well as the response of pathologic fracture should be suspected. to daily activities and home therapies. Other key Plain film radiographs show a radiolucent or information, such as history of previous lesions at cystic area 2 cm to 3 cm in size in the bone, other sites in the body, may help discern primary surrounded by a sclerotic margin. These lesions and metastatic lesions. 214 CHAPTER 34 generally do not expand or violate natural cortical centrally. Early in the development of these lesions margins. They are generally found eccentrically they may not be apparent on radiographs despite located in the calcaneus, and in the shaft in long significant clinical symptoms. Fortunately, the . increased availability of CT and MRI have made Treatment is indicated when there is the risk detection of these and other lesions easier. of pathologic fracture. Treatment most often Treatment of these lesions is en bloc resection includes curettage, irrigation, and packing of the where possible, however, curettage has also been lesions with autogenous or allogeneic bone. The described. author also routinely obtains cultures and biopsies for definitive diagnosis. For lesions of the Chondroblastoma calcaneus, the author recommends a lateral Chondroblastomas are rare, accounting for only 7o/o curuilinear incision, which avoids and protects the of primary bone tumors. Interestingly, however peroneal tendons and sural nerye. 700/0, of these lesions in one study were found in the foot, and most commonly in the calcaneus or talus according to \7a11ing. Kricun went on to Aneurysmal bone cysts are less common than evaluate the position of occurrence within the heel unicameral bone cysts. When occurring in the foot, in 74 cases. This lesion typically arises from an they are found in the tarsals and metatarsals. These active epiphyseal plate in a patient between 10 and lesions are usually found in patients in their 2nd or 20 years of age. Patients present with pain and 3rd decade of life, and may present as a palpable swelling due to the subchondral location. tender mass. Radiographically, these lesions appear radiolucent Radiographically, these lesions are fairly with a sclerotic margin. distinct on plain fi1ms, showing bulging of the Treatment usually consists of curettage and coltex, and trabeculation or "honeycombing" inside grafting. How-ever, in more aggressive lesions or in the lesion. The author finds it helpful to look for a cases of recurrence, removal of the articular bubbly-appearance inside the overall lesion. cartilage and primary arthrodesis may yield good Aspiration or opening of the aneurysmal bone results with decreased risk of recurrence and need cyst produces a hemorrhagic fluid. Treatment is for additional potentially debilitating procedures. debridement, irrigation, and packing with bone chips. There is limited case experience of a Giant Cell Tumor of Bone technique under evaluation where demineralized Giant Cell Tumors are rare in the foot, and account bone paste is introduced under CT or fluoroscopic for 5o/o of all biopsied primary bone tumors. In a guidance through biopsy needle, following a review of 7782 lesions, less than 2o/o occtrred in the aspiration and irrigation. Early reports are foot. Vhen these lesions do arise in the foot, promising, although there is some concern of the however, they are most often noted in the possible increased recurrence risk of calcaneus and metatarsals. Patients who present with giant cell tumors / are usually in their third decade of life. Vhen the Osteoid osteoma and osteoblastoma are essentially malignant variety is encountered, men are affected histologically identical, but differ in size. three times as often as women. Radiographically, Convention dictates that lesions less than 2 cm are these lesions are radiolucent with a small zone of osteoid osteoma while lesions greater than 2 cm peripheral sclerosis. are osteoblastomas. The most common location in Giant CeIl Tumors are treated with curettage. the foot is the tarsal bones. Typically the patients However, due to their more aggressive nature, are 10- to 25-years-old and present with gradually adjuvant treatments are also recommended worsening symptoms which are more pronounced including the use of intra-lesional cryotherapy, in the evening. The pain is not improved with Phenol, polymethylmethacrylate, or cauterization. immobllization, but shows good, transient relief of The recurrence rate of these lesions is between symptoms with aspirin. 70o/o and 30%. Higher stage lesions, and recurrent Radiographically, there is radiolucency in the lesions may require wide excision and reconstruc- periphery with radiolucency or calcification tive arthrodesis, or even amputation. CHAPTER 34 215

Intraosseous Lipoma the patient seeks care. Radiographically, the Intraosseous lipomas are rare, accounting for only enchondroma radiates from the medullary area, expansion and 0.1o/o of all bone tumors. \7hen present, they are with varying degrees of cortical usually located in the metaphyseal area of the host thinning. bone. This lesion occurs equally in males and Treatment includes curettage and packing females, and has no particular age predilection. with bone graft. Smaller digital lesions may also be Intraosseous lipomas are frequently asymptomatic, effectively treated with phalangectomy. Care but risk of fracture is of specific concern. should be taken to completely remove all suspect potential for The radiographic appearance is usually of a areas, as the enchondroma does have well-defined, but expansile lesion. The lesion may recurrence as a benign or malignant lesion. result in thinning of the cortex and also may not show any significant sclerosis of the margin. The Brodie's Abscess treatment for the symptomatic lipoma or one at risk Although the Brodie's abscess is not a tumor, it is of pathologic fracture includes curettage and included for completeness sake. The chronic packing with bone chips. abscess of bone may also have a radiographic appearance of radiolucency with marginal Ganglion of Bone sclerosis. The patient history and a careful clinical Repofis of intraosseous ganglions in the calcaneus examination are paramount in obtaining an and cuboid have appeared several times in the accurate clinical diagnosis and effective treatment. recent literature. Despite these reports, the History of puncture wounds or pediatric hematoge- interest. condition is extremely rare. The typical patient is nous are of pafiicular young to middle-aged, and there is equal Treatment of the abscess should include a occurrence in both sexes. Presenting symptoms thorough removal of all necrotic tissue back to may include intermittent aching, which is healthy normal-appearing margins. The author PMMA aggravaled by activity. Soft tissue swelling is rare, favors the use of gentamicin-impregnated This is in addition to but has been noted with some cases. beads following debridement. Plain radiographs reveal an epiphyseal or appropriate systemic antibiosis. The antibiotics intra- metaphyseal location with a round or oval lytic should be chosen based on a full set of anaerobic, area. The a:rea may be unilocular or multilocular. operative cultures including aerobic, Commonly, there is no or fungal, and acid fast swabs. bulging of the cortex. However, the author has experience with a case of a ganglion of bone which MALIGNANT LESIONS not only expanded but broke through the cortex of the metatarsal. Ewing's Sarcoma Treatment includes curettage and packing Ewing's sarcoma is the most common primary of the lesions with bone graft material. malignant tumor of bone in the foot, as reported by Intraoperatively, windowing of the cortex of the the IESS (Intergroup Ewing's Sarcoma Study). involved bone reveals the typical mucinous, Despite it being the most common, it is uncommon straw-colored fluid of a ganglion. A1so, a delicate in the foot, accounting for only 10 of 377 patients capsule or lining may be seen and should be evaluated. In the IESS group of 10 lesions, 5 were thoroughly removed with the curette. located in the calcaneus, 1 in the talus, 2 in the metatarsal, and 1 in the distal phalanx of the Enchondroma hallux. The calcaneal lesions correlated with a An Enchondroma represents the second most higher mortality rate (4 of 5 patients deceased) as common cartilaginous tumor of the skeletal system. compared with metatarsal lesions. The typical patient is between the 2nd and 6th The typical Ewing's patient is 5 to 15 years decades of life. Presentation may include swelling old, and presents with concerns of pain and and intermittent pain. Although the heel may be swelling. Radiographically, the most common affected, the phalanges and metatarsals are far finding is permeation, although expansion is also more common sites of presentation. Pathologic frequently noted. Interestingly, however, periosteal fracture is common, and may be the reason that reaction is less commonly found in the foot. 216 CHAPTER 34

Further workup should include a bone scan, chest remodeling or invasion of adjacent osseous radiographs, and oncology consult before structures. Treatment may include local excision or entertaining biopsy or other invasive treatments. amputation and radiation or chemotherapy. Treatment commonly includes chemotherapy, radiation treatment, and amputation. Metastatic Lesions Metastatic lesions, although rare, do occur from Osteogenic Sarcoma time to time in the foot. The calcaneus is again a Osteogenic sarcoma is rarely seen in the foot. favored site of occurrence. Sites of primary disease \7hen cases are reviewed, the most common site is which most frequently metastasize to the foot the metatarsals. Osteogenic sarcoma is divided into include breast, bladder, lung, kidney, and five types which include medullary, periosteal, colorectal disease. One genetalization that has mixed fype, sclerosing, and chondrosarcoma type. been made is that metastasis to the foot is more Patients are typically between 10 and 20 years old. likely to occur from sub-diaphragmatjc sites of Radiographically, osteogenic sarcoma invades primary disease, while super-diaphragmatic ad)acent soft tissues and exhibits rapid bony primary tumors are more likely to metastasize to destn-rction and proliferation. Metastasis is early the hand and upper extremity. and common, therefore, treatment includes excision or amputation and very close follow-up. CASE PRESENTATION

Chondrosarcorrta The following case will show a surgical approach Chondrosarcomas are also a rareTy encountered which the author has found helpful in approaching malignant tumor in the foot. This lesion is most lesions of the heel. A 35-year-old female presented common in men over the age of 25. \X4ten present, initially with a concern of aqrpical heel pain on the they most frequently appear in the calcaneus, left foot. Radiographs showed no heel spur phalanges, and metatarsals. Most commonly, formation. A well-circumscribed lytic lesion was chondrosarcomas arise de novo but occasionally noted in the calcaneus,but it was initially felt only may arise from enchondromas or osteo- to be an incidental finding (Fig. 1). chondromas. Radiographically, the lesion is After two months of conserwative care which expansile with cortical destruction and expansion included NSAIDs, oral corticosteroids, injections, into the soft tissues. MRI may be very helpful in and biomechanical control, the patient remained evaluating these lesions. symptomatic. An MRI was obtained to further Treatment of this malignancy is dependent on evaluate the heel, and showed extensive cystic the size and location of the lesion. However, the changes to the body of the calcaneus (Figs. 2A, prognosis is much better with chondrosarcoma 2B). Treatment options were discussed, and the than with many other malignant bone tumors. patient decided on surgical interuention, due to the persistent pain. Synovial Sarcoma Following appropriate medical evaluation and clearance, the patient was taken operating The synovial sarcoma, though not a lesion of bone, to the room and positioned decubitus is included here due to the location of a tumor in the lateral position a bean bag. The previously encountered by the author. Ten to on left heel was then approached twenly percent of synovial sarcomas occur around through a modified European calcaneal fracture (Fig. the foot and ankle. In Kirby's study this was noted incision 3). The dissection plane was taken to periosteum prior to be the most common malignant lesion in the to any under- foot. mining. The lateral flap was then elevated with the sural nerve The synovial sarcoma is most often seen in undisturbed, and the periosteal flap was raised with the peroneal tendons. patients between the third and fifth decades of life. After completion the soft tissue dissection, There is a higher frequency in women than men of the planned cortical window was marked with 4 (3,2). Frequently, patients may present with a safe-stop concern of a gradtally-enlarging "lump." The origin drill holes. The window was then cut and removed (Fig. The is most commonly from joint capsule, tendon 4). fluid contents of the cyst were cultured prior sheath, or bursae. Radiographs may show to evacuation. CHAPTER 34 217

Figr:re 1. Lateral plain film shoq,ing lytic changes, Figure 2A. Sagittal plane MRI

Figure 28. Coronal MRI sho$,ing the signiticant ertent of involvement Figure 3. Incisional plan shoning the course of the peroneal tendons of the calcaneal body ancl tuberosity. and sural nen'e (dottecl Line).

V.:t:::t:

Figure ,1. \Tindow-ing of the latcral l'al1 of the celcaneus exposcs the Figure 5. Aggressive curettage r.vas unciefiaken removing the cyst cyst. lining ancl exposing ran'canccllous surface n'here possible. 218 CITAPTER 34

Figure 6. Follor.ving curettage ancl irrigation, tlte cyst was packed with Figure 7. Chips u'ere manuzrlly impacted s,ith a bone tamp coftico-canccllous chips.

Figure 8. The corlical winclow r.vas replaccd and anchored u,'ith Figure !. The completed closurc prior to clressing ancl cast application. periosteel closure.

The cyst was then curetted and irrigated, included , aneurysmal bone including the inner surface of the corticai window cyst, ganglion of bone, intraosseous lipoma, (Fig. 5). The wound was packed with a mkture of and Brodie's abscess. The MRI and preoperative col'tico-cancellous chips and demineralizecl bone laboratory studies effectively eliminated all paste (Fig. 6). Followlng impaction of the graft (Fig. possibilities, with the exception of unicameral bone 7) the cortical window was replaced, and the cyst. The MRI also mapped the lesion and the periosteum was sutured to hold the fragment in surgical approach. No significant consideration was place (Fig. 8). Layered closure was then performed given to malignant tumors, due to the typical over a closed-suction drain (Fig. 9). A modified benign appearance on plain film radiograph, with Jones compression dressing was then applied. a sclerotic, well-defined margin and surrounding The patient's postoperative course was normal appearing bone. unremarkable. Range of motion exercises were This article has presented a review of the instituted at four weeks, and partial-weight bearing more common lyic lesions commonly found in the at six weeks. Full-weight bearing was allowed in a heel, and may raise the readers index of suspicion removable cast,brace at eight weeks, and the in atypical lesions to insure that more aggressive patient was returned to shoes at ten weeks. lesions are diagnosed and treated in a timely This case shows an example of a fairly large fashion. cystic lesion of the calcaneus. Differential diagnosis CHAPTER 34 219

BIBLIOGRAPITY

Johnston MR: Epiderniolo$, of soft tissue and bone tumors of the foot. Clin Pod Med Surg L0(4'):581-607, 1993. Kirby E, Shereff M, Lewis M: Soft tissue tumors and tumor like lesions of the foot. An analysis of 83 cases. J Bone Joint Surg 7IA:62I, 1989. Kircun M, Kircun R, Haskin M: Chondroblastoma of the calcaneus, radiographic features with emphasis on location. Am J Roent 728:673, 1977. Shereff MJ, Cr-rllivan $7T, Johnson I(A: Osteoid Osteoma of the foot../ Bone Joint Surg 55-A(5):638-641, 1983 638-641 Shirley SK, Askin FB, Gilula LA, Vietti TJ, Thomas PR, Siegal GP, Reinus \flR, Kissane JXrt, Nesbit ME: Ewing's Sarcoma in bones of the hands and feet: a clinicopathologic study and review of the literature. .[ Clin Oncol 3(.5'):686-697 , 1985. \7i11iams RP, Pechero G: Management of soft tissue and bone tumors of the foot. Clin Pod Med Surg 1,0(.4-)1717-725,1993. \Walling AK, Gasser SI: Soft tissue and bone tumors about the foot and ankle. Clin Sports Med 13(.4):909-938, 1994. \7u KK: Osteoid Osteoma of the foot. .J Foot Surg 30(.2):1.90-194, 1991. Yeager KK, Mitchell M, Sartorius DJ, Resnick D: Diagnostic imaging of bone tumors. Clin Pod Meci Surg 5(.1):859-875, L988. Yeager KK, Mitchell M, Sartorius DJ: Diagnostic imaging approach to bone tumors of the foot. J Foot Surg 30(.2):1.97-208,1991.